Review Article Heterogeneous Metal Catalysts for Oxidation ...downloads.hindawi.com/journals/jnm/2014/192038.pdf · Review Article Heterogeneous Metal Catalysts for Oxidation Reactions

Review ArticleHeterogeneous Metal Catalysts for Oxidation Reactions

Md Eaqub Ali1 Md Motiar Rahman1 Shaheen M Sarkar2 and Sharifah Bee Abd Hamid1

1 Nanotechnology and Catalysis Research Centre (NanoCat) Universiti of Malaya 50603 Kuala Lumpur Malaysia2 Faculty of Industrial Sciences and Technology University Malaysia Pahang 26300 Gambang Kuantan Malaysia

Correspondence should be addressed to Md Eaqub Ali eaqubaligmailcom

Received 11 August 2014 Accepted 9 October 2014 Published 22 December 2014

Academic Editor Amir Kajbafvala

Copyright copy 2014 Md Eaqub Ali et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Oxidation reactions may be considered as the heart of chemical synthesis However the indiscriminate uses of harsh and corrosivechemicals in this endeavor are threating to the ecosystems public health and terrestrial aquatic and aerial flora and faunaHeterogeneous catalysts with various supports are brought to the spotlight because of their excellent capabilities to accelerate therate of chemical reactions with low costThey alsominimize the use of chemicals in industries and thus are friendly and green to theenvironment However heterogeneous oxidation catalysis are not comprehensively presented in literature In this short review weclearly depicted the current state of catalytic oxidation reactions in chemical industries with specific emphasis on heterogeneouscatalysts We outlined here both the synthesis and applications of important oxidation catalysts We believe it would serve as areference guide for the selection of oxidation catalysts for both industries and academics

1 Introduction

Oxidation reactions play a pivotal role in chemical industryfor the production of many crucial compounds [1] Forexample selective oxidation of alkyl substituted benzene pro-duces alcohol and ketones which have significant biologicaland mechanistic interest in modern organic synthesis [2]Ethylbenzene is a representative compound of various linearand phenyl-substituted alkanes and is a model substrate tostudy alkane oxidation reactions The oxidation productsof ethylbenzene include acetophenone and 1-phenylethanolwhich have been used as precursors for the synthesis of a widevariety of drugs such as hydrogel [3] optically active alcohols[2] hydrazones [4] benzalacetophenones (chalcones) [5]tear gas and resins [6]

In the past efforts were made for the oxidation of alkylsubstituted benzene to useful products such as benzylic andallylic ketones by adding stoichiometric amounts of strongoxidants such as chromium (IV) reagents permanganatestert-butyl hydroperoxide (TBHP) selenium oxide (SeO

2)

ruthenium (VIII) oxide hydrogen peroxide nitric acid andoxygen [7ndash9] However most of these chemicals are eithertoxic or corrosive to reactor wall unstable in atmosphericconditions nonspecific in actions which produce manyundesirable side products and that increases the purification

cost and environment pollutant [7ndash9] These traditionaltransformation schemes are also time consuming and cannotbe recycled [10]

The green chemistry approaches must meet health andenvironmental safeties and use very little chemicals reducingboth cost and time [11] Catalytic approaches might beconsidered as green since specific chemical transformationcould be achieved within very short time with the addition ofvery little catalysts significantly reducing production cost aswell as health and environmental risks [12 13] According tothe North American Catalysis Society approximately 35 ofglobal GDP rest on catalysts and the use of catalysts in indus-try are increasing 5 per year [14] Currently more than 60of chemical synthesis and 90 of chemical transformationsin chemical industries are using catalysts [15 16] In 2013the sales of catalysts were between 155 billion USD and theturnover in industries using catalyst was 14 trillion USD

Homogeneous catalyst has been extensively used in theoxidative process for the manufacturing of bulk as well asfine chemicals This is because of its efficiency in bringinghuge influences in chemical conversion via the same phasecatalysis reaction [17] In the recent time some transitionmetal ion complexes have shown high selectivity efficiency

Hindawi Publishing CorporationJournal of NanomaterialsVolume 2014 Article ID 192038 23 pageshttpdxdoiorg1011552014192038

2 Journal of Nanomaterials

Table 1 Major features advantages and disadvantages of the commonly used support materials

Supports materials Features Advantages Disadvantages References

Alumina

(1) Hardness(2) High melting point andhigh compression strength(3) Resistant to abrasionand chemical attack(4) High thermalconductivity

(1) Thermally stable(2) Randomly ordered(3) High surface area andpore volume(4) Well-ordered pore(5) Narrow pore size

(1) Difficult to control thehydrolysis rate ofaluminum precursors

[73]

Silica

(1) Tendency to form largenetworks(2) Found in nature andliving organisms(3) Hardness

(1) High efficiency(2) High selectivity(3) Highly stable(4) Mechanical strength

(1) Low compatibility(2) Formation ofaggregatesagglomerates

[74]

Zeolite(1) Microporous(2) Inertness(3) Excellent electronconductivity

(1) Highly effective(2) Less or no corrosion(3) No waste or disposalproblems(4) High thermo stability(5) Easy set-up ofcontinuous processes(6) Great adaptability topractically all types ofcatalysis

(1) Irreversible adsorptionor steric blockage of heavysecondary products(2) Impossibility of usingmicroporosity(3) Difficult to exploit theshape selectivity

[75 76]

Carbon(1) Nonmetallic(2) Tetravalent(3) Porous structure

(1) High mechanicalstrength(2) Large surface area(3) Excellent electronconductivity(4) Good elasticity(5) Thermal stability(6) Inertness

(1) High temperaturephysical activation(2) Expensive(3) Emission of greenhousegasses during pyrolysis

[77 78]

and reproducibility to catalyze the reaction under mild con-ditions The single catalytic entity in homogeneous catalystscan act as a single active site which can speed up reaction andreduce the reaction time [18] However homogeneous cat-alytic processes produce huge waste materials significantlydisrupting the environmental and ecological stability [19ndash21]One of the main disadvantages to the use of these types ofcatalysts is the ease of separating of the comparatively affluentcatalysts from the reaction mixtures at the end of reaction[9 19 22] Homogeneous catalysts also cause corrosion tothe industrial materials and some of them are deposited onthe reactor wall To get rid of these problems and minimizeenvironmental hazards the homogenous catalysts could beprepared by the dispersion of metal on an insoluble solidsupports via covalent anchoring to keep the metal on thesurface where catalysis reaction takes place [18 22]

Heterogeneous catalyst is considered to be a better choicefor the synthesis of commodity materials [23ndash25] Nowadayssilica carbon clay zeolite metal oxide polymers and othermesoporous materials are being used as inorganic solidsupports [26 27] Supported materials can be obtained ascomplexes with transition metals and Schiff base ligandsby heterogenization process [28] The application of sup-ported polymers in catalytic oxidation has gained muchattention because of their inertness and nontoxic nonvolatileand recyclable criteria [29] Among inorganic supports

the mesoporous materials have been proven to be idealcatalyst supports due to their three-dimensional open porenetwork structures high surface area and porosity highreusability and heat stability and uniform and interconnectedpores which offer a reliable and well-separated atmospherefor the deposition of dynamic components and interactivesurfaces between the catalysts and reactants [30ndash38] Varioussupport materials along with their major features are pre-sented in Table 1

Heterogeneous catalysts promote oxidation reactions viaattracting oxygen fromoxidants such as TBHP (tert-BuO

2H)

and HP (H2O2) [39 40] In the last decade TBHP has been

used as oxidant for various oxidation reactions such as alkylbenzene and benzyl alcohol oxidation In this review wedescribed heterogeneous catalysts their synthesis schemeson various supports and applications in selected oxidationreactions The comparative features of homogeneous andheterogeneous catalysts are presented in Figure 1

2 Heterogeneous Catalysts

In heterogeneous catalysis reaction the catalysts and reac-tants exist in different phases In reality the vast majority ofheterogeneous catalysts are solids and the vast majority ofreactants are either gases or liquids [14] A phase separationcatalysis reaction greatly helps in reactant product and

Journal of Nanomaterials 3

Disadvantages

Advantages

Major features

Homogeneous

Major features

Catalysts

Heterogeneous

Advantages

Disadvantages

(1) Difficult separation

(3) Huge waste materials (4) Product

(2) Reactor corrosion

(1) Dissolves in reaction medium hence all catalytic sites are available for reaction

(5) Complicated handling

(1) Nonselective to chiral catalysis

(3) Use as fixed beds

(1) Same phase (catalysts reactants and products)

(2) Co dissolved

(3) High selectivity

(4) Easy separation

(2) Reusable (1) Stable

(2) Difficult to study and hence reactionmechanisms are often unknown

(1) Different phases (catalysts reactants and products)

(2) Poor selectivity

(3) No solvent required

Figure 1 Special features advantages and disadvantages of homo- and heterogeneous catalysts

catalyst separation at the end of the reaction Heterogeneouscatalysts are also easier to prepare and handleThese catalystsconsist of fine nanosized powders supported on technicallyinert oxide substrates exhibiting all possible crystallographicfaces The catalyst is often a metal to which chemical andstructural promoters or poisons are added to enhance theefficiency andor the selectivity Currently heterogeneouscatalysis is dominating in industries for chemical trans-formation and energy generation Approximately 90 ofall industrial practices indulge in heterogeneous catalysisThe most recent applications of heterogeneous catalysts aresummarized in Table 2

3 Heterogeneous Metal Catalystsin Oxidation Reactions

Over the last few decades scientists have paid tremen-dous attention to heterogeneous catalysts to overcome the

limitations of their homogeneous counterparts to increaseproducts yields and minimize side reactions Herein wereported a summary of selected oxidation reactions catalyzedby supported metal catalysts

31 Conversion of Glucose to Gluconic Acid Recently theaerobic oxidation of glucose to gluconic acid (Figure 2)has gained much consideration because of its water-solublecleansing properties and application in food additives andbeverage bottle detergents [41] In the past the oxidation ofglucose was carried out via biochemical pathways which arecumbersome multistep process not recyclable and expen-sive [42] The development of catalytic route is probably analternative pathway for the large scale production of gluconicacid from glucose In 1970s researchers used to dope Ptor Pd onto some heavy metals such as bismuth Howeverseveral limitations such as instability poor selectivity andlow conversion rate were encountered with this procedure


Table2Re

cent

scenario

inheterogeneou

scatalysis

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2013

Fenano

catalyst

Immob

ilizatio

nEthylbenzenecyclohexeneand

benzylalcoho

loxidation

[18]

2013

AuA

l 2O3Au

CDeposition

-precipitatio

ncatio

nica

dsorption

Glucose

oxidation

[79]

2013

AuPtb

imetallic

nano

particles

mdashGlucose

oxidation

[80]

2013

Goldnano

particles

supp

ortedon

Mg(OH) 2nano

sheets

Colloidaldepo

sition

COoxidation

[81]

2013

AuTiO

2supp

ortedon

ferritics

tainles

sste

elmon

olith

sDire

ctanionice

xchange

COoxidation

[82]

2013

Nanop

orou

sgold

Electro

lytic

dissolution

COoxidation

[83]

2013

P123-stabilized

Au-Agalloy

Coredu

ction

Benzylalcoho

loxidatio

n[84]

2013

Alumina-supp

ortedgold-ruthenium

bimetallic

catalysts

Incipientw

etnessIm

pregnatio

nDeposition

Precipitatio

nCO

oxidation

[54]

2013

AuCuO

catalysts

Cop

recipitatio

nAlcoh

oloxidation

[85]

2013

Cerium

mod

ified

silver

Impregnatio

nAlkylarom

aticcompo

unds

[86]

2013

Pd-Aucatalyst

Deallo

ying

Methano

lelectrooxidation

[87]

2013

AuZnO

andAu

TiO

2catalysts

Colloidaldepo

sition

Methano

loxidatio

n[88]

2013

Microstructured

AuN

i-fiberc

atalyst

Incipientimpregnatin

gAlcoh

oloxidation

[89]

2013

Nanocrystallin

eAgandAu

-Agalloys

supp

ortedon

titania

Deposition

Precipitatio

nCO

oxidation

[90]

2013

Nanosized

Ausupp

ortedon

3-Dordered

mesop

orou

sMnO

2

Deposition

Precipitatio

nOxidatio

nof

carbon

mon

oxidebenzeneandtoluene

[91]

2013

AuFeO119909

Cop

recipitatio

nCO

oxidation

[92]

2013

Nanosized

ruthenium

particlesd

ecorated

carbon

nano

fibers

Solgel

p-Cy

meneo

xidatio

n[93]

2012

AuC

Incipientw

etness

impregnatio

nGlucose

oxidation

[94]

2012

CeA

lPO-5

molecular

sieves

mdashDiphenylm

ethane

oxidation

[10]

2012

Nanosized

gold

onSiO

2Stob

erCy

clohexene

andD-glucose

oxidation

[95]

2012

AuSiO

2Disp

ersio

nSilaneso

xidatio

n[47]

2012

Nanogold-m

esop

orou

ssilica

mdashCO

oxidation

benzylalcoho

loxidatio

n[96]

2012

Nanosized

gold

Disp

ersio

nAlkylbenzeneo

xidatio

n[40]

2012

AgSB

A-15

Impregnatio

nAlkylsubstituted

arom

atics

[35]

2012

Bimetallic

Au-PdMgO

Sol-immob

ilizatio

n(SI)and

adsorptio

n-redu

ction(A

R)Be

nzylalcoho

loxidatio

n[97]


Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2012

InverseF

e 2O

3Au

(111)m

odelcatalysts

mdashCO

oxidation

[98]

2012

Silica-supp

ortedAu

-Cualloy

mdashAlcoh

oloxidation

[99]

2012

Goldnano

particlessup

ported

onMgO

Deposition

-precipitatio

nAlcoh

oloxidation

[100]

2012

Silica-supp

ortedAu

-CuO119909

Oxidativ

edeallo

ying

Ethano

loxidatio

n[101]

2011

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

oxidation

[102]

2011

Au-PdC

Impregnatio

nGlyoxalandglucoseo

xidatio

n[103]

2011

Pd-Tes

uppo

rted

catalysts

Repeated

impregnatio

nGlucose

oxidation

[104]

2011

Goldnano

particlessup

ported

onfunctio

nalized

mesop

orou

ssilica

One-pot

Synthesis

Cyclo

hexane

oxidation

[105]

2011

Silicas

uppo

rted

cobalt(II)salencomplex

Immob

ilizatio

nAlkylbenzeneo

xidatio

n[70]

2011

Goldnano

wire

smdash

Oxidatio

nof

benzyliccompo

unds

[106]

2011

Cu32[PM

o 12O

40]SiO

2Incipientw

etness

impregnatio

nBe

nzylicalcoho

l[107]

2010

Goldnano

particlesd

epositedon

cellu

lose

Deposition

-reductio

ngrinding

metho

dGlucose

oxidation

[41]

2010

Metallopo

rphyrin

boun

dto

silica

Immob

ilizatio

nEthylbenzene

oxidation

[68]

2010

Hydroph

obized

palladium

Vapo

rdeposition

Glucose

oxidation

[108]

2010

Supp

ortedgold

catalysts

Colloidalgold

depo

sition

COoxidation

[109]

2010

AuH

MScatalysts

Impregnatio

nanddirect

synthesis

Benzylalcoho

loxidatio

n[63]

2010

Mob

ilizedgold

nano

particles

Goldsol

Second

aryalcoho

lsoxidation

[67]

2010

Mesop

orou

sCo 3O

4andAu

Co 3O

4catalysts

Nanocastin

gEthylene

oxidation

[110]

2010

Metal-organicfram

eworksupp

ortedgold

nano

particles

Colloidaldepo

sition

Alcoh

oloxidation

[111]

2010

PtA

l 2O3

Impregnatio

nHeavy

hydrocarbo

nsoxidation

[112]

2009

AuTiO

2Deposition

-precipitatio

nAlcoh

oloxidation

[113]

2009

Co(Ac

O) 2M

n(Ac

O) 2

Dire

ctcond

ensatio

np-xylene

oxidation

[114]


Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2009

Nickelsub

stitutedcopp

erchromite

spinels

Cop

recipitatio

nAlkylsubstituted

benzeneo

xidatio

n[9]

2007

Goldcatalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[115]

2007

MCM

-48molecular

sieve

mod

ified

with

SnCl

2Po

st-synthesis

mod

ificatio

nAlcoh

oloxidation

[65]

2007

CuO-im

pregnatedmesop

orou

ssilica

Impregnatio

nBe

nzeneo

xidatio

n[116]

2006

Supp

ortedgold

catalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[117]

2006

Au-C

uOA

l 2O3PtA

l 2O3catalysts

Deposition

-precipitatio

nim

pregnatio

nProp

enea

ndprop

aneo

xidatio

n[118]

2006

Manganese

containing

mesop

orou

sMCM

-41and

Al-M

CM-41

molecular

sieves

Impregnatio

np-iso

prop

yltolueneo

xidatio

n[119]

2005

Goldcatalysts

mdashAlcoh

oloxidation

[120]

2005

AuC

Immob

ilizatio

nGlucose

oxidation

Alcoh

oloxidation

[64]

2005

Goldim

mob

ilizedmesop

orou

ssilica

Immob

ilizatio

nCy

clohexane

oxidation

[121]

2005

Nitrou

soxide

over

MFI

zeolites

Hydrothermal

Benzeneo

xidatio

n[122]

2005

CoA

PO-5

molecular

sieves

Hydrothermal

Cyclo

hexane

oxidation

[123]

2004

Carbon

-sup

ported

gold

Goldsol

Glucose

oxidation

[124]

2004

Mn-containing

MCM

-41

Impregnatio

nEthylbenzene

oxidation

[72]

2003

CoO119909C

eO2

Cop

recipitaion

Carbon

mon

oxideo

xidatio

n[125]

2002

Goldcatalysts

Immob

ilizatio

nGlucose

oxidation

[126]

2002

Mn(Salen)MCM

-41

mdashOlefin

sepo

xidatio

n[127]

2002

NanostructuredCu

O119909C

eO2

Gas-con

densation

Carbon

mon

oxideo

xidatio

n[128]

2002

Nano-Au

Catalysts

mdashCa

rbon

mon

oxideo

xidatio

n[55]

2001

AuTiO

2Au

TiO

2SiO

2Deposition

-precipitatio

nProp

enee

poxidatio

n[129]

2000

Gold-titaniacatalysts

Deposition

-precipitatio

nProp

yleneo

xidatio

n[130]

1999

Golddispersedon

TS1and

other

titanium-con

tainingsupp

orts

Disp

ersio

nProp

enee

poxidatio

n[131]

1998


Deposition

-precipitatio

nProp

ylenee

poxidatio

n[61]

1996

Heterop

olycatalysts

containing

Ru(III)

andRh

(III)p

articles

mdashAlkaneo

xidatio

n[132]

1996

Goldsupp

ortedon

ZnOandTiO

2Cop

recipitatio

namp

Deposition

-precipitatio

nCa

rbon

mon

oxideo

xidatio

n[133]

1996

Au-TiO

2Incipientw

etness

impregnatio

nCa

rbon

mon

oxideo

xidatio

n[134]

1995

Bism

uthprom

oted

palladium

catalysts

Ionexchange

Glucose

oxidation

[42]


HO HO

OOH

OHOH

OH OH

OHOH

OH

OH O

Glucose Gluconic acid

Catalysts

Figure 2 Conversion of glucose to gluconic acid

Si

ClCl Cl

H

trimethyl(phenyl)silane Tetramethylsilane Trichlorosilane

Si CH3

CH3

CH3

Si CH3

CH3

CH3

H3C

Scheme 1

H OH

Dimethylphenylsilane Dimethylphenylsilane

THF RTSi Si

CH3

CH3 CH3

CH3

+ H2O + H2

AuSiO2

Scheme 2

without any supporting materials [42] On the other handbismuth on palladium or PtPd on carbon supports demon-strated high selectivity and stability and excellent conversionrate overcoming the limitations of the heavy metal supportsSome features such as catalyst type and the role of bismuthsupport are still a disputed issue [42]

Prati and Rossi (1997) [43] studied the oxidation of12-diols and found excellent selectivity with gold catalystover platinum and palladium catalysts The gold catalystshowed unusual selectivity in the oxidation of alcohol to itscorresponding carboxylates whereas Pd or Pt showed lowerselectivity to oxidize ethane-12-diol From this observationthey also concluded that Au is less sensitive to overoxidationandor self-poisoning than Pd or Pt Gold clusters andnanoparticles (NPs) deposited on the metal oxide surfacesuch as Al

2O3and ZrO

2demonstrated unexpected catalytic

activity in the oxidation of glucose with better turnover fre-quency (TOF reaction rate per Au atom surface) In additionto carbon andmetal oxide supports some inorganic polymerssuch as silica could be used as catalytic supports for smallAu nanoparticles (gt10 nm in diameter) [43] The catalyticeffect of Au nanoparticles (25 nm) held by polymer gelwas demonstrated by Ishida et al [44] Polymer supportedAuNPs exhibited higher catalytic performance than AuC inthe oxidation of primary alcohols such as benzyl alcohol tobenzaldehyde in absence of base [45] The catalytic activityof various catalysts for glucose oxidation is summarized inTable 3

32 Selective Oxidation of Silanes to Silanols Silane is aninorganic compound having the silicon atom with chemical

formula SiH4 It is a colorless flammable gas with a sharp

and repulsive smell somewhat similar to that of acetic acidSilane has interest as a precursor of silicon metal Silanemay also be referred to many compounds containing sili-con such as trichlorosilane (SiHCl

3) trimethyl(phenyl)silane

(PhSi(CH3)3) and tetramethylsilane (Si(CH

3)4) (Scheme 1)

The oxidation of silane to corresponding silanols (asfor example dimethylphenylsilane to dimethylphenylsilanolScheme 2) is a key reaction to manufacture building blocksfor the synthesis of silica based polymers [46] and nucle-ophilic couplers in organic synthesis In the past silanolssynthesis was often carried out by stoichiometric oxidationof organosilanes hydrolysis of halosilanes or alkali treat-ment of siloxanes which incurred environmental hazards Incontrast the catalytic oxidation of silanes with water is anecofriendly process since it produces silanols with high selec-tivity producing only hydrogen as a by-product Supportedgold nanoparticles have shown higher catalytic activity andselectivity on silane oxidation over other transition metalcatalysts [47] Mitsudome et al [48] oxidized aliphatic silanesto silanols using hydroxyapatite supported AuNPs in waterat 80∘C Nanoporous gold also showed high reactivity andselectivity towards silanes in acetone at room temperature[49]

Recently John et al [50] have synthesized carbon nano-tube-supported gold nanoparticles which showed turnoverfrequency (TOF) of 18000 hminus1 for silane oxidation in tetrahy-drofuran (THF) at room temperature However the prepa-ration of Au CNT (carbon nanotube) hybrids involved amultistep layer-by-layer assembly which needed expensivereagents which have limited its practicability Li et al [47]


Table3Oxidatio

nof

glucoseb

yvario

uscatalysts

Nam

eofcatalysts

Preparationmetho

dRe

actio

ncond

ition

Mainprod

uct

Selectivity

()Re

ferences

SubstrateOxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)

pHSolvent

Goldnano

particleso

ncellu

lose

Deposition

-redu

ction

O2

mdash60

95Water

Gluconica

cid

mdash[41]

AuA

l 2O3

Deposition

-precipitatio

nO

27

6090

Water

Gluconica

cid

97[79]

AuC

Catio

nica

dsorption

O2

760

90Water

Gluconica

cid

97[79]

Au-PdC

Impregnatio

nO

220

5092

5mdash

Gluconica

cid

mdash[103]

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

H2O

240

90mdash

Sodium

D-gluconate

99[102]

AuC

Goldsol

mdash30

5095

mdashGluconica

cid

45[124]

Nanosized

AuSiO

2Stob

erH

2O2

2430

92Water

Gluconica

cid

80[95]

Pb-TeSiO

2Re

peated

impregnatio

nO

215

6090

mdashGluconica

cid

884

[104]

AuPtb

imetallic

nano

particle

Vacuum

drying

O2

260

95mdash

Gluconica

cid

mdash[80]


Table 4 Comparison of supported gold catalysts for the oxidation of triethylsilane [47]

Catalysts Reaction condition Conversion rate () Yield ()Substrate Solvent Reaction temperature Time (min) Ausubstrate (mol)

AuSiO2

Triethylsilane

Water 25∘C 3 04 99 99AuTiO2 Water 25∘C 3 04 81 81AuFe2O3 Water 25∘C 3 04 36 36AuZnO Water 25∘C 3 04 89 89AuCeO2 Water 25∘C 3 04 98 98

Catalyst

Decomposition

H2 + O2 H2O2

2H2O2

H2O + 12O2

Hydrogenation H2

Scheme 3 Hydrogen peroxide formation hydrogenation and decomposition

prepared silica supported gold catalysts for the selectiveoxidation of silanes However they observed that silicasupported gold catalysts aremore active than reducible oxides(TiO2 Fe2O3 CeO

2 etc) supported AuNPs Highly dis-

persed silica supported gold catalysts override the reducibleoxides supported AuNPs due to superior adsorption of silanesubstrate on silica support Surprisingly for the oxidationof dimethylphenylsilane in THF at room temperature theAuSiO

2catalyst afforded a TOF of 59400 hminus1 which is the

highest TOF reported to dateThe other oxide supported gold catalysts such as

AuTiO2 AuZnO and AuFe

2O3

were less active thanAuSiO

2 and they afforded a maximum conversion of 90

However the activity of AuCeO2catalyst was very similar to

the AuSiO2catalyst (Table 4)

33 Oxidation of Hydrogen to Hydrogen Peroxide (H2O2)

H2O2is an essential chemical which has long been used

mainly as strong oxidant in various oxidative reactions andbleaching agent as well as a disinfectant It is a green oxidantsince its sole by-product is water In the current decades alot of attention has been paid to the green catalysts and greenchemicals to ensure safety issues in health and environmentIndustries have been using supported Pd catalysts for morethan 90 years for the direct synthesis of H

2O2from H

2and

O2 However the synthesized H

2O2is unstable and under-

goes low-temperature decomposition or hydrogenation towater (Scheme 3) [51] Recently Edwards et al [52] usedAu-catalysts synthesized via coprecipitation or deposition-precipitation method and found very low H

2O2conversion

rateThey also observed that the addition of Au to Pd catalystsby impregnation enhances H

2O2formation They compared

five different catalyst supports namely Al2O3 Fe2O3 TiO2

SiO2

and carbon and found the high conversion withcarbon-supported Au-Pd (Au-PdC)

In 2010 Song et al [53] observed that KMnO4treated

activated carbon in an acidic solution enhances H2O2pro-

duction (78) from hydroxylamine due to the creation ofsurface active quinoid species during oxidation Structure

and surface analyses revealed that KMnO4treatment pro-

duced more phenolic but less carboxylic groups on theactivated carbon under acidic condition confirming thecrucial role of the quinoid groups It was also proposed thatthe quinoid groups served as electron acceptors and redoxmediators in the formation of H

2O2[53]

34 Carbon Monoxide (CO) Oxidation In the last decadeCOoxidation has become an important research area becauseof its involvement in a number of processes such asmethanolsynthesis water gas shift reaction carbon dioxide lasersand automotive exhaust controls [54] Carbon monoxide isa lethal gas for animal life and toxic to the environment[55] The oxidation of CO is a difficult process and hencea highly active oxidation catalyst is required for its efficientremoval from the environment [55] In the past the gold wasconsidered to be inert for CO oxidation [56]

However Haruta et al [57] demonstrated that highlydispersed gold prepared on various metal oxide supportsby coprecipitation and deposition-precipitation methods ishighly active in CO oxidation even below 0∘C temperatureThey found that catalytic performance significantly dependson the catalysts preparation methods and the highest activitywas demonstrated by TiO

2supported gold or platinum

catalysts prepared by deposition-precipitation (DP)The goldcatalysts prepared by photodeposition (PD) and impregna-tion (IMP) methods were less active than those preparedby deposition-precipitation This is because the catalystsprepared by DP method contain higher loading of Au(gt2wt) on smaller particles and are with better dispersionCollectively these features enable the catalyst to show higheractivity oxidizingsim100ofCOat temperatures belowminus20∘CIn 1997 Yuan et al [58] synthesized highly active goldcatalysts for CO oxidation simply by grafting Au-phosphinecomplexes (AuL

3NO3or Au

9L8(NO3)3 L = PPh

3) onto

precipitated Ti(OH)4surfaces This Au-phosphine-Ti(OH)

4

complex was active even below the 0∘C Apart from this Na+ions positively andClminus ions negatively affect the Au-catalyzed


C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus

Figure 3 Plausible mechanism for CO oxidation on oxide supported gold catalyst On the left a CO molecule is chemisorbed onto a lowcoordination number gold atom (yellow sphere) and a hydroxyl ion is moved from the oxide support (pink sphere) to an Au (III) ioncreating an anion vacancy On the right they have reacted to form a carboxylate group and an oxygen molecule occupies the anion vacancyas O2minus (white sphere) This then oxidizes the carboxylate group by abstracting a hydrogen atom forming carbon dioxide and the resultinghydroperoxide ionHO

2

minus then further oxidizes carboxylate species to form another carbon dioxide restoring two hydroxyl ions to the supportsurface completing the catalytic cycle (Adapted with permission from Springer) [145]

O

Catalysts

Propene epoxide

Polyether polyols (66) Propene glycols (30) Propene glycols ether (4)

Polyurethanes or foam Polyesters Solvents

CH3CH=CH2 + O2 + H2CH3CH2ndashCH2 + H2O

Scheme 4 Synthetic products from propene epoxidation reaction

CO oxidation Figure 3 represents the initial stages of COoxidation at the edge of an active gold particle

35 Epoxidation of Propene The oxidation of propene toepoxide is an important reaction for the synthesis of variousindustrial chemicals such as polyether polyols (precursorof polyurethane or foams) propene glycol and propeneglycol ethers (Scheme 4) [59] In the past chlorohydrin andhydroperoxide mediated processes were used for the syn-thesis of propene epoxide Chlorohydrin process producesenvironmentally hazardous chlorinated by-products and thehydroperoxide process is much expensive and producesstyrene and tert-butyl alcohol as by-products Silver catalystswere used in this reaction but poor selectivity and turnoverwere observed [60] However titania supported gold effi-ciently catalyzed the epoxidation reaction at 30ndash120∘C withmore than 90 selectivity in the presence of hydrogen [61]

36 Oxidation of Alcohol The oxidation of alcohols to itscorresponding aldehydes or ketones is a crucial reaction inorganic synthesis Ketones specially acetone are widely usedin the production of various organic as well as fine chemicals[62] Traditional chemical routes use stoichiometric chem-icals such as chromium (VI) reagents dimethyl sulfoxidepermanganates periodates or N-chlorosuccinimide whichare expensive and hazardous Several homogeneous catalystssuch as Pd Cu and Ru are found to selectively catalyzealcohol oxidation However homogeneous catalysis requireshigh pressure oxygen andor organic solvent incurring costand environmental burdens [63] The present ecologicaldeterioration has forced researchers to look for novel andenvironmentally friendly catalytic schemes for the oxidationof alcohol Prati and Porta [64] demonstrated that AuCcatalyst shows higher selectivity toward aldehyde in the oxi-dation of primary alcohols Subsequently Endud and Wong[65] synthesized porous SiSn bimetallic catalyst through


Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene

Ferrocenecarboxaldehyde Fe nanocatalysts on nanohybrid

SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH

Nanohybrid SiO2Al2O3-APTMS

SiO2Al2O3-APTMS

24h reflux

NH2 +

Figure 4 Synthesis of heterogeneous Fe nanocatalysts by the immobilization of Fe on functionalized SiO2-Al2O3mixed oxide 3-

aminopropyltrimethoxysilane (3-APTMS) Adapted with permission from Elsevier [18]

postsynthesis modification of rice husk ash as Si precursorand SnCl

2as tin source Using TBHP oxidant the tin

modifiedMCM-48 showedmuch selectivity toward aldehydeor ketone in the oxidation of benzyl alcohols [65]

Chaki et al [66] looked into the catalytic activity ofgold by adding silver (5ndash30Ag content) into gold particlesfor aerobic oxidation of alcohols It showed that lt10Agaccelerates the catalytic activity of Au Recently Kidwai andBhardwaj [67] described that gold nanoparticles (AuNP)are highly active in alcohol oxidation with hydrogen perox-ide as oxidant They observed that AuNPs with extendedsurface area exhibit higher catalytic activity over othersAdditionally gold catalyzed reactions are free from chemicalhazards and toxic solvents and produce water as the only sideproduct This methodology was a great contribution towardsthe development of sustainable green chemistry

4 Heterogeneous Catalysts in the Oxidation ofAlkyl Substituted Benzene

In this Section we described various catalysts their syntheticschemes and performance for the oxidation of alkyl substi-tuted benzenes which are an important compound in organicsynthesis

41 Fe Nanocatalysts Habibi et al [18] synthesized Fe nano-catalyst which oxidized alkyl substituted benzene Theyprepared the heterogeneous nano-Fe catalyst on the SiO

2

Al2O3supports through the covalent immobilization of fer-

rocenecarboxaldehyde which acts as iron source (Figure 4)In the presence of tert-butyl hydroperoxide (TBHP) oxi-dant this catalyst produces acetophenone benzaldehydeand benzoic acid from ethylbenzene with 89 selectivity toacetophenone (Scheme 5)

This catalytic scheme provided certain benefits includingthe low cost raw materials commercially available simple

Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid

Scheme 5 Products from the catalytic oxidation of ethyl aromaticwith novel Fe nanocatalysts

chemicals and catalysts reusability for the further oxidationof ethylbenzene The side chain carbonyl group is producedby TBHP oxidant without any solvent at a substrateTBHPratio of 1 1 at 50ndash120∘C in a day

This novel Fe nanocatalyst exhibited higher conversionrate (gt84) of ethylbenzene with 90 selectivity towardacetophenone which is the precursor of many products suchas resins chalcones drugs fine chemicals and opticallyactive alcohols The comparative performances of variouscatalysts for alkyl benzene oxidation are given in Table 5

42 Manganese (III) Porphyrin Complexes in the Oxidation ofAlkyl Substituted Benzene Silica boundmanganese (III) por-phyrin complexes [Mn(TMCPP)](TMCPP 5 10 15 20-tet-rakis-(4-methoxycarbonylphenyl)-2123H-porphyrin] selec-tively catalyzes the oxidation of alkyl substituted benzeneto its corresponding ketone Ghiaci et al [68] synthesizedmanganese porphyrin complexes by immobilization onto


Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO

Surface silanol Group of silica

3-Aminopropyltriethoxysilane SF-3-APTS

NaH TMCPP THF reflux

Mn porphyrin complex

(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2

72h N2 MnCl2middot4H2ODMF 140∘C 4h N2

Figure 5 The synthetic scheme of manganese porphyrin complex by immobilization on silica support (Adapted with permission fromElsevier [68])

silica support This catalyst complex showed high selec-tivity and efficiency toward hydrocarbon oxidation due toits shape selectivity toward substrate and matrix supportthat provided special atmosphere for CndashH oxidation [69]For catalysts synthesis the silica gel was made active athigh temperature (500∘C) followed by modification with 3-aminopropyltriethoxysilane that acts as silica source underinert gas (N

2) atmosphere The details of the preparation of

this catalyst are described elsewhere (Figure 5) The effects ofvarious parameters such as oxidants solvents and tempera-ture on the oxidation of substituted benzene were studied andthe maximum catalysis was obtained with TBHP oxidant at150∘C under solvent free conditions

43 AgSBA-15 Catalysts in the Oxidation of Alkyl SubstitutedBenzene The CndashH bond of alkyl substituted benzene can beselectively oxidized to its corresponding ketones by AgSBA-15 catalysts with TBHP as oxidant Recently Anand et al [35]synthesized the silica supported Ag catalysts by impregnationmethod and found that AgSBA-15 is an environmentallyfriendly catalyst for the breaking of alkyl benzene CndashHbond They used tetraethyl orthosilicate as silica source andsilver nitrate as silver source The schematic of the syntheticscheme is given in Figure 6 and the details could be obtainedfrom bibliography [35] The prepared catalyst showed thebest conversion rate in presence of tert-butyl hydroperoxide

Table 6 Effect of various solvents on the AgSBA-15 catalyzedoxidation of alkyl substituted benzene at 90∘C in presence of 70TBHP oxidant [35]

Solvent Conversion () Selectivity ()Acetophenone 1-phenylethanol

Toluene 92 92 8DMF 15 80 20Acetonitrile 85 86 12Water 65 89 10No solvent 92 99 1

oxidant with 92 and 99 selectivity towards ketone undersolvent free condition (Table 6)

44 Nickel Substituted Copper Chromite Spinels Anotherform of catalysts called nickel substituted copper chromite(Cu2Cr2O5) spinels can efficiently catalyze the oxidation

of alkyl substituted benzene George and Sugunan (2008)[9] synthesized nickel substituted copper chromite spinelsusing copper nitrate nickel nitrate and chromium nitratevia coprecipitation method In the first step a solution ofcopper nickel and chromium nitrate was prepared in waterThe pH of the solution adjusted to 65ndash80 with the stepwiseaddition of 15 ammonium solution under constant stirring


TEOS

Calcination

PEO PPO

Pluronic P-123 Pluronic P-123 solution SBA-15 AuSBA-15

H2O HCl AgNO3

Figure 6 Synthesis of AgSBA-15 catalysts by impregnation method

+ +

Copper nitrate Nickel nitrate Chromium nitrate Solution of copper nickel and chromium nitrate

Adjust pH 65ndash80 by adding 15 ammonium solution

heat

PrecipitantsNickel substituted copperchromite spinels

Figure 7 Synthesis of nickel substituted copper chromite spinels

Table 7 Recipe for the preparation of various nickels substitutedcopper chromite spinels [9]

Catalysts composition (Cu1minus119909

Ni119909Cr2O4) Designation

CuCr2O4 (119909 = 0) CCrCu075Ni025Cr2O4 (119909 = 025) CNCr-1Cu05Ni05Cr2O4 (119909 = 05) CNCr-2Cu025Ni075Cr2O4 (119909 = 075) CNCr-3NiCr2O4 (119909 = 1) NCr

The precipitate was maintained at 70ndash80∘C for 2 h and agedfor 24 h Finally the precipitate was filtered washed anddried at 353K for 24 h and calcined at 923K for 8 h to getthe spinels Figure 7 depicts the complete procedure for thesynthesis of nickel substituted copper chromite spinel Therecipe of George and Sugunan (2008) [9] for the preparationof nickel substituted copper chromite spinels catalyst is givenin Table 7

Catalytic activity of each spinel for the oxidation of ethyl-benzenewas studied in detail [9] and it was found that CNCr-2 type chromite spinel provides the maximum conversionrate (561) with 687 selectivity towards acetophenone(Table 8) under solvent free conditions [9] Nickel substituted

chromites were compared with those simple chromites andthe nickel chromites demonstrated superior activity

45 Silica Supported Cobalt (II) Salen Complex The aero-bic oxidation of alkyl substituted benzene was successfullycarried out over silica supported cobalt (II) salen complexin presence of O

2in N-hydroxyphthalimide (NHPI) solvent

[70] Rajabi et al [70] prepared the silica supported cobaltsalen complexes by chemical modification of di-imine cobaltcomplex using cobalt acetate as a source of cobalt ion(Figure 8) At first Salicylaldehyde was added to the excessamount of absolute MeOH at room temperature and the3-aminopropyltrimethoxysilane was added to the mixtureThe solution turned into yellow color due to the formationof imine which contains a carbon-nitrogen double bond ahydrogen atom (H) or an organic group is attached to thenitrogen The addition of cobalt (II) acetate to the iminecompound allows the new ligands to complex the cobaltPrior to surfacemodification nanoporous silicawas activatedby inserting into concentrated HCl and subsequent washingwith deionized water (Figure 8)

Rajabi et al [70] also investigated the catalytic activityof immobilized cobalt catalysts for ethylbenzene oxidation


Table 8 Oxidation of ethylbenzene by nickel substituted copper chromite spinels [9]

Catalysts Conversion () Selectivity ()Acetophenone 1-phenylethanol Others

CCr 329 139 834 27CNCr-1 447 519 464 17CNCr-2 561 687 281 32CNCr-3 555 556 396 48NCr 202 591 194 215Reaction conditions temperature 70∘C time 8 h EB TBHP ratio 1 2 catalyst weight 01 g solvent 10mL acetonitrile [9]

Table 9 Oxidation reaction of ethylbenzene by reused silica supported Co(II) catalysts

Entry Run Temperature (∘C) Selectivity () Yield ()Alcohol Acetophenone

1 First 100 9 91 782 Second 100 10 90 783 Third 100 10 90 774 Fourth 100 10 90 70

+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO

Salicylaldehyde 3-Aminopropyltrimethoxysilane Imine compound

Cobalt (II) acetate

Di-imine cobalt complex

Surface modification

NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2

Figure 8 Preparation of silica supported cobalt (II) catalysts by surface chemical modification Adapted with permission from Elsevier [70]

with O2in N-hydroxyphthalimide and other solvents and

acetic acid was found to be the best solvent The selectivityand the conversion rate were increasedwith temperatureTheheterogeneous catalysts were reused four times and a littlechange in activity was observed (Table 9)

46 Nanosized Gold-Catalysts Materials in nanometer sizeshow properties distinct from their bulk counterpartsbecause nanosized clusters have electronic structures thathave high dense states [71] Biradar and Asefa (2012) [40]described the oxidation of alkyl substituted benzene oversilica supported gold nanoparticles Supported AuNPs wereprepared by in situ impregnation method [40] to keepthe catalyst well dispersed on the support surfaces Briefly

a solution of Pluronic P-123 was added to water andhydrochloric acid Desired amount of TEOS (tetraethoxysi-lane) was added to the aqeous acidic Pluronic P-123 solutionunder stirring The resulting precipitates was subsequentlyfiltered and washed several time under ambient state toget mesostructured SBA-15 For the synthesis of SBA-15supported gold catalysts HAuCl

4solution was made in

ethanolwater (1 4 ratios) andwaswell dispersed on the silicasupport (Figure 9) The lower sized AuNPs demonstratedhigher TON (turnover number) and lower TOF (turnoverfrequency) (Table 10) Solvent effects on oxidation reactionwere studied and acetonitrile appeared to be the best solventIt produced 79 conversion with 93 selectivity towards theketone products


Table 10 Oxidation of ethylbenzene by three different types of AuSBA-15 catalysts [40]

Entry Catalystssample(Au average size)

Wt(mmolAug) Conversion () Selectivity () TON TOF (hminus1)

Ketone Alcohol1 SBA-15 mdash sim0 sim0 sim0 sim0 sim0

2 AuSBA-15 catalyst(54 plusmn 12 nm)

108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7

Reaction condition substrate ethylbenzene 1mmol oxidant 80 TBHP (aq) 2mmol solvent acetonitrile 10mL catalyst AuSBA-15 sample with 15mgoverall mass reaction temperature 70∘C internal standard chlorobenzene (05mL) reaction time 36 h and reaction atmosphere air [40]

PEO PPO


TEOSCalcination

HAuCl4H2O HCl

Figure 9 Schematic diagram for the synthesis of SBA-15 supported gold catalysts

MnMn

Cetyl trimethyl ammonium bromide MCM-41

Stirring CalcinationFiltration wash[CH3ndashCOOminus]2 Mn2+

Figure 10 Schematic diagram for the synthesis of Mn containing MCM-41 catalysts

47 Mn-Containing MCM-41 Catalyst for the Vapor PhaseOxidation of Alkyl Substituted Benzene Vapour-phase oxi-dation of alkyl substituted benzene was performed withcarbon dioxide-free air as an oxidant over MnO

2impreg-

nated MCM-41 catalysts [72] Vetrivel and Pandurangan [72]synthesizedMCM-41 on C

16H33(CH3)3N+Brminus templateThe

Mn containing MCM-41 mesoporous molecular sieves wereprepared by impregnating MCM-41 into manganese acetatesolutions under stirring overnight Finally the solution wasfiltered washed evaporated and calcined at a specific tem-perature to obtain Mn containing MCM-41 (Figure 10) Theyalso optimized the reaction conditions by varying reactiontemperature weight hourly space velocity and time onstream They carried out a number of reactions with thesix types of washed and unwashed Mn containing catalystsIn every case acetophenone was the major products whichincrease with the increase of metal content in the catalystsThe high conversion rate to acetophenone was obtained withMn-MCM-41 catalysts with high Mn content The unwashedcatalysts showed higher reactivity than that of washed onedue to the high density of active site in the unwashed catalysts

5 Preparation Method ofSupported Metal Catalysts

A high number of methods have been proposed for the syn-thesis supported heterogeneous metal catalysts [71] Table 11is a summary of the major methods frequently used incatalysts synthesis

6 Concluding Remark

This review provides an extensive overview of the literatureregarding the applications and synthesis of some heteroge-neous catalysts for oxidation catalysis Advantages and dis-advantages of certain candidature support materials are pre-sented Special emphasis is given to heterogeneous catalysisspecially the metal-support synergy The role of appropriatesolvent that codissolves the catalysts and substrate to easethe pretreatment and oxidation process is tabulated for betterunderstanding In line with the goal of industrial processreaction conditioning and utilization of appropriate andcheap catalysts are briefly outlined Future research should


Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp

ortedmetalcatalystcomplexes

inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa

multistepprocessesfor

thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo

rmation(cyclizationdehydration)

ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions

(sulfatearsenatesand

anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong

interactionbetweenthem

etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching

(a)Itissyntheticmetho

dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]


focus on the synthesis and application of more efficientheterogeneous catalysts as well as synergizing the catalyst costfor large scale synthesis

Conflict of Interests

The authors declare that they have no conflict of interestsregarding the publication of this paper

Acknowledgment

The authors acknowledge the University of Malaya Fund noRP005A-13 AET

References

[1] K Hemalatha G Madhumitha A Kajbafvala N Anupama RSompalle and S Mohana Roopan ldquoFunction of nanocatalystin chemistry of organic compounds revolution an overviewrdquoJournal of Nanomaterials vol 2013 Article ID 341015 23 pages2013

[2] T Mehler W Behnen J Wilken and J Martens ldquoEnantiose-lective catalytic reduction of acetophenone with borane in thepresence of cyclic 120572-amino acids and their corresponding 120573-amino alcoholsrdquo Tetrahedron Asymmetry vol 5 no 2 pp 185ndash188 1994

[3] V N Hasirci ldquoPVNOmdashDVB hydrogels synthesis and charac-terizationrdquo Journal of Applied Polymer Science vol 27 no 1 pp33ndash41 1982

[4] G Newkome and D Fishel ldquoPreparation of hydrazones ace-tophenone hydrazonerdquo Organic Syntheses vol 50 pp 102ndash1021988

[5] R T Blickenstaff W R Hanson S Reddy and R WittldquoPotential radioprotective agentsmdashVI Chalcones benzophe-nones acid hydrazides nitro amines and chloro compoundsRadioprotection of murine intestinal stem cellsrdquo Bioorganic ampMedicinal Chemistry vol 3 no 7 pp 917ndash922 1995

[6] M Ali M Rahman and S B A Hamid ldquoNanoclustered gold apromising green catalysts for the oxidation of alkyl substitutedbenzenesrdquo Advanced Materials Research vol 925 pp 38ndash422014

[7] I Kani and M Kurtca ldquoSynthesis structural characterizationand benzyl alcohol oxidation activity of mononuclear man-ganese(II) complex with 221015840-bipyridine [Mn(bipy)

2(ClO4)2]rdquo

Turkish Journal of Chemistry vol 36 no 6 pp 827ndash840 2012[8] P Gallezot ldquoSelective oxidation with air on metal catalystsrdquo

Catalysis Today vol 37 no 4 pp 405ndash418 1997[9] K George and S Sugunan ldquoNickel substituted copper chromite

spinels preparation characterization and catalytic activity inthe oxidation reaction of ethylbenzenerdquo Catalysis Communica-tions vol 9 no 13 pp 2149ndash2153 2008

[10] S Devika M Palanichamy and V Murugesan ldquoSelectiveoxidation of diphenylmethane to benzophenone over CeAlPO-5 molecular sievesrdquo Chinese Journal of Catalysis vol 33 no 7-8pp 1086ndash1094 2012

[11] G Centi and S Perathoner ldquoCatalysis and sustainable (green)chemistryrdquo Catalysis Today vol 77 no 4 pp 287ndash297 2003

[12] J H Clark and D J Macquarrie ldquoHeterogeneous catalysis inliquid phase transformations of importance in the industrialpreparation of fine chemicalsrdquo Organic Process Research ampDevelopment vol 1 no 2 pp 149ndash162 1997

[13] Y Wang X Wang and M Antonietti ldquoPolymeric graphiticcarbon nitride as a heterogeneous organocatalyst from photo-chemistry to multipurpose catalysis to sustainable chemistryrdquoAngewandte Chemie International Edition vol 51 no 1 pp 68ndash89 2012

[14] D Cole-Hamilton and R Tooze ldquoHomogeneous catalysismdashadvantages and problemsrdquo in Catalyst Separation Recovery andRecycling pp 1ndash8 Springer 2006

[15] N R Shiju andVV Guliants ldquoRecent developments in catalysisusing nanostructured materialsrdquo Applied Catalysis A Generalvol 356 no 1 pp 1ndash17 2009

[16] I Fechete Y Wang and J C Vedrine ldquoThe past present andfuture of heterogeneous catalysisrdquo Catalysis Today vol 189 no1 pp 2ndash27 2012

[17] A Zapf and M Beller ldquoFine chemical synthesis with homoge-neous palladium catalysts examples status and trendsrdquo Topicsin Catalysis vol 19 no 1 pp 101ndash109 2002

[18] D Habibi A R Faraji M Arshadi and J L G FierroldquoCharacterization and catalytic activity of a novel Fe nano-catalyst as efficient heterogeneous catalyst for selective oxida-tion of ethylbenzene cyclohexene and benzylalcoholrdquo Journalof Molecular Catalysis A Chemical vol 372 pp 90ndash99 2013

[19] M R Maurya A Kumar and J Costa Pessoa ldquoVanadiumcomplexes immobilized on solid supports and their use ascatalysts for oxidation and functionalization of alkanes andalkenesrdquo Coordination Chemistry Reviews vol 255 no 19 pp2315ndash2344 2011

[20] A Dhakshinamoorthy M Alvaro and H Garcia ldquoMetal-organic frameworks as heterogeneous catalysts for oxidationreactionsrdquo Catalysis Science and Technology vol 1 no 6 pp856ndash867 2011

[21] Q Yin J M Tan C Besson et al ldquoA fast soluble carbon-freemolecular water oxidation catalyst based on abundant metalsrdquoScience vol 328 no 5976 pp 342ndash345 2010

[22] A Sivaramakrishna P Suman E V Goud et al ldquoRecentprogress in oxidation of n-alkanes by heterogeneous catalysisrdquoResearch and Reviews in Materials Science and Chemistry vol 1no 1 pp 75ndash103 2012

[23] P Sudarsanam L Katta G Thrimurthulu and B M ReddyldquoVapor phase synthesis of cyclopentanone over nanostructuredceria-zirconia solid solution catalystsrdquo Journal of Industrial andEngineering Chemistry vol 19 no 5 pp 1517ndash1524 2013

[24] A Kajbafvala H Ghorbani A Paravar J P Samberg EKajbafvala and S K Sadrnezhaad ldquoEffects of morphology onphotocatalytic performance of Zinc oxide nanostructures syn-thesized by rapidmicrowave irradiationmethodsrdquo Superlatticesand Microstructures vol 51 no 4 pp 512ndash522 2012

[25] K-H Kim and S-K Ihm ldquoHeterogeneous catalytic wet airoxidation of refractory organic pollutants in industrial wastew-aters a reviewrdquo Journal of Hazardous Materials vol 186 no 1pp 16ndash34 2011

[26] A Corma H Garcıa and F X Llabres I Xamena ldquoEngineeringmetal organic frameworks for heterogeneous catalysisrdquo Chemi-cal Reviews vol 110 no 8 pp 4606ndash4655 2010

[27] A Kajbafvala S Zanganeh E Kajbafvala H R Zargar M RBayati and S K Sadrnezhaad ldquoMicrowave-assisted synthesisof narcis-like zinc oxide nanostructuresrdquo Journal of Alloys andCompounds vol 497 no 1-2 pp 325ndash329 2010

[28] M Yoon R Srirambalaji and K Kim ldquoHomochiral metal-organic frameworks for asymmetric heterogeneous catalysisrdquoChemical Reviews vol 112 no 2 pp 1196ndash1231 2012


[29] K C Gupta A K Sutar and C-C Lin ldquoPolymer-supportedSchiff base complexes in oxidation reactionsrdquo CoordinationChemistry Reviews vol 253 no 13-14 pp 1926ndash1946 2009

[30] A Kumar V P Kumar B P Kumar V Vishwanathan and KV R Chary ldquoVapor phase oxidation of benzyl alcohol overgold nanoparticles supported on mesoporous TiO

2rdquo Catalysis

Letters vol 144 no 8 pp 1450ndash1459 2014[31] D R Burri I R Shaikh K-M Choi and S-E Park ldquoFacile

heterogenization of homogeneous ferrocene catalyst on SBA-15and its hydroxylation activityrdquo Catalysis Communications vol8 no 4 pp 731ndash735 2007

[32] S Sreevardhan Reddy B David Raju V Siva Kumar A HPadmasri S Narayanan and K S Rama Rao ldquoSulfonic acidfunctionalized mesoporous SBA-15 for selective synthesis of 4-phenyl-13-dioxanerdquoCatalysis Communications vol 8 no 3 pp261ndash266 2007

[33] D J Kim B C Dunn P Cole et al ldquoEnhancement in thereducibility of cobalt oxides on a mesoporous silica supportedcobalt catalystrdquo Chemical Communications no 11 pp 1462ndash1464 2005

[34] R Burri K-W Jun Y-H Kim J M Kim S-E Park and JS Yoo ldquoCobalt catalyst heterogenized on SBA-15 for p-xyleneoxidationrdquo Chemistry Letters vol 31 no 2 pp 212ndash213 2002

[35] N Anand K H P Reddy G V S Prasad K S RamaRao and D R Burri ldquoSelective benzylic oxidation of alkylsubstituted aromatics to ketones over AgSBA-15 catalystsrdquoCatalysis Communications vol 23 pp 5ndash9 2012

[36] J H Nam Y Y Jang Y U Kwon and J D NamldquoDirect methanol fuel cell Pt-carbon catalysts by using SBA-15nanoporous templatesrdquo Electrochemistry Communications vol6 no 7 pp 737ndash741 2004

[37] M Arsalanfar A A Mirzaei H R Bozorgzadeh A Samimiand R Ghobadi ldquoEffect of support and promoter on the cat-alytic performance and structural properties of the Fe-Co-Mncatalysts for Fischer-Tropsch synthesisrdquo Journal of Industrialand Engineering Chemistry vol 20 no 4 pp 1313ndash1323 2014

[38] A Kajbafvala M R Shayegh M Mazloumi et al ldquoNanostruc-ture sword-like ZnOwires rapid synthesis and characterizationthrough a microwave-assisted routerdquo Journal of Alloys andCompounds vol 469 no 1-2 pp 293ndash297 2009

[39] P J Kropp G W Breton J D Fields J C Tung and B RLoomis ldquoSurface-mediated reactions 8 Oxidation of sulfidesand sulfoxides with tert-butyl hydroperoxide and OXONErdquoJournal of the American Chemical Society vol 122 no 18 pp4280ndash4285 2000

[40] A V Biradar and T Asefa ldquoNanosized gold-catalyzed selectiveoxidation of alkyl-substituted benzenes and n-alkanesrdquo AppliedCatalysis A General vol 435-436 pp 19ndash26 2012

[41] T Ishida H Watanabe T Bebeko T Akita and M HarutaldquoAerobic oxidation of glucose over gold nanoparticles depositedon celluloserdquoApplied Catalysis A General vol 377 no 1 pp 42ndash46 2010

[42] M Besson F Lahmer P Gallezot P Fuertes and G FlecheldquoCatalytic oxidation of glucose on bismuth-promoted palla-dium catalystsrdquo Journal of Catalysis vol 152 no 1 pp 116ndash1211995

[43] L Prati and M Rossi ldquoChemoselective catalytic oxidation ofpolyols with dioxygen on gold supported catalystsrdquo Studies inSurface Science and Catalysis vol 110 pp 509ndash515 1997

[44] T Ishida H Watanabe T Bebeko and M Haruta ldquoAerobicoxidation of glucose over gold nanoparticles deposited on

celluloserdquo Applied Catalysis A General vol 377 no 1-2 pp 42ndash46 2010

[45] T Ishida S Okamoto R Makiyama and M Haruta ldquoAerobicoxidation of glucose and 1-phenylethanol over gold nanoparti-cles directly deposited on ion-exchange resinsrdquo Applied Cataly-sis A General vol 353 no 2 pp 243ndash248 2009

[46] R Murugavel M G Walawalkar M Dan H W Roesky andC N R Rao ldquoTransformations of molecules and secondarybuilding units to materials a bottom-up approachrdquo Accounts ofChemical Research vol 37 no 10 pp 763ndash774 2004

[47] W Li A Wang X Yang Y Huang and T Zhang ldquoAuSiO2as

a highly active catalyst for the selective oxidation of silanes tosilanolsrdquo Chemical Communications vol 48 no 73 pp 9183ndash9185 2012

[48] T Mitsudome A Noujima T Mizugaki K Jitsukawa and KKaneda ldquoSupported gold nanoparticle catalyst for the selectiveoxidation of silanes to silanols in waterrdquo Chemical Communica-tions no 35 pp 5302ndash5304 2009

[49] N Asao Y Ishikawa N Hatakeyama et al ldquoNanostructuredmaterials as catalysts nanoporous-gold-catalyzed oxidation oforganosilanes with waterrdquo Angewandte Chemie vol 49 no 52pp 10093ndash10095 2010

[50] J John E Gravel A Hagege H Li T Gacoin and EDoris ldquoCatalytic oxidation of silanes by carbon nanotube-goldnanohybridsrdquo Angewandte ChemiemdashInternational Edition vol50 no 33 pp 7533ndash7536 2011

[51] P Landon P J Collier A J Papworth C J Kiely and GJ Hutchings ldquoDirect formation of hydrogen peroxide fromH2O2using a gold catalystrdquo Chemical Communications no 18

pp 2058ndash2059 2002[52] J K Edwards AThomas B E Solsona P Landon A F Carley

and G J Hutchings ldquoComparison of supports for the directsynthesis of hydrogen peroxide from H

2and O

2using Au-Pd

catalystsrdquo Catalysis Today vol 122 no 3-4 pp 397ndash402 2007[53] W Song Y Li X Guo J Li X Huang and W Shen ldquoSelective

surface modification of activated carbon for enhancing thecatalytic performance in hydrogen peroxide production byhydroxylamine oxidationrdquo Journal of Molecular Catalysis AChemical vol 328 no 1-2 pp 53ndash59 2010

[54] O A Kirichenko E A Redina N A Davshan et al ldquoPrepara-tion of alumina-supported gold-ruthenium bimetallic catalystsby redox reactions and their activity in preferential CO oxida-tionrdquo Applied Catalysis B Environmental vol 134-135 pp 123ndash129 2013

[55] T V Choudhary C Sivadinarayana C C Chusuei A KDatye J P Fackler Jr and D W Goodman ldquoCO oxi-dation on supported nano-Au catalysts synthesized from a[Au6(PPh

3)6](BF4)2complexrdquo Journal of Catalysis vol 207 no

2 pp 247ndash255 2002[56] M Haruta N Yamada T Kobayashi and S Iijima ldquoGold cata-

lysts prepared by coprecipitation for low-temperature oxidationof hydrogen and of carbon monoxiderdquo Journal of Catalysis vol115 no 2 pp 301ndash309 1989

[57] M Haruta S Tsubota T Kobayashi H Kageyama M J Genetand B Delmon ldquoLow-temperature oxidation of CO over goldsupported on TiO

2 120572-Fe

2O3 and CO

3O4rdquo Journal of Catalysis

vol 144 no 1 pp 175ndash192 1993[58] Y Yuan A P Kozlova K Asakura H Wan K Tsai and Y

Iwasawa ldquoSupported Au catalysts prepared from Au phosphinecomplexes and as-precipitated metal hydroxides characteriza-tion and low-temperature CO oxidationrdquo Journal of Catalysisvol 170 no 1 pp 191ndash199 1997


[59] B K Min and C M Friend ldquoHeterogeneous gold-basedcatalysis for green chemistry low-temperature CO oxidationand propene oxidationrdquo Chemical Reviews vol 107 no 6 pp2709ndash2724 2007

[60] T A Nijhuis MMakkee J A Moulijn and BMWeckhuysenldquoThe production of propene oxide catalytic processes andrecent developmentsrdquo Industrial and Engineering ChemistryResearch vol 45 no 10 pp 3447ndash3459 2006

[61] T Hayashi K Tanaka and M Haruta ldquoSelective vapor-phaseepoxidation of propylene overAuTiO

2catalysts in the presence

of oxygen and hydrogenrdquo Journal of Catalysis vol 178 no 2 pp566ndash575 1998

[62] Y-H Kim S-K Hwang J W Kim and Y-S Lee ldquoZirconiasupported ruthenium catalyst for efficient aerobic oxidationof alcohols to aldehyderdquo Industrial amp Engineering ChemistryResearch vol 53 no 31 pp 12548ndash12552 2014

[63] C Y Ma J Cheng H L Wang et al ldquoCharacteristics ofAuHMS catalysts for selective oxidation of benzyl alcohol tobenzaldehyderdquo Catalysis Today vol 158 no 3-4 pp 246ndash2512010

[64] L Prati and F Porta ldquoOxidation of alcohols and sugars usingAuC catalysts part 1 Alcoholsrdquo Applied Catalysis A Generalvol 291 no 1-2 pp 199ndash203 2005

[65] S Endud and K-LWong ldquoMesoporous silicaMCM-48molec-ular sieve modified with SnCl

2in alkaline medium for selective

oxidation of alcoholrdquo Microporous and Mesoporous Materialsvol 101 no 1-2 pp 256ndash263 2007

[66] N K Chaki H Tsunoyama Y Negishi H Sakurai and TTsukuda ldquoEffect of Ag-doping on the catalytic activity ofpolymer-stabilized Au clusters in aerobic oxidation of alcoholrdquoThe Journal of Physical Chemistry C vol 111 no 13 pp 4885ndash4888 2007

[67] M Kidwai and S Bhardwaj ldquoApplication of mobilized goldnanoparticles as sole catalyst for the oxidation of secondaryalcohols into ketonesrdquoApplied Catalysis A General vol 387 no1-2 pp 1ndash4 2010

[68] M Ghiaci F Molaie M E Sedaghat and N DorostkarldquoMetalloporphyrin covalently bound to silica Preparationcharacterization and catalytic activity in oxidation of ethylbenzenerdquo Catalysis Communications vol 11 no 8 pp 694ndash6992010

[69] I N Lykakis and M Orfanopoulos ldquoPhotooxidation of arylalkanes by a decatungstatetriethylsilane system in the presenceof molecular oxygenrdquo Tetrahedron Letters vol 45 no 41 pp7645ndash7649 2004

[70] F Rajabi R Luque J H Clark B Karimi andD J MacQuarrieldquoA silica supported cobalt (II) Salen complex as efficient andreusable catalyst for the selective aerobic oxidation of ethylbenzene derivativesrdquo Catalysis Communications vol 12 no 6pp 510ndash513 2011

[71] A D Banadaki and A Kajbafvala ldquoRecent advances in facilesynthesis of bimetallic nanostructures an overviewrdquo Journal ofNanomaterials vol 2014 Article ID 985948 28 pages 2014

[72] S Vetrivel and A Pandurangan ldquoVapour-phase oxidation ofethylbenzene with air over Mn-containing MCM-41 meso-porous molecular sievesrdquoApplied Catalysis A General vol 264no 2 pp 243ndash252 2004

[73] P Kim Y Kim H Kim I K Song and J Yi ldquoSynthesis andcharacterization of mesoporous alumina for use as a catalystsupport in the hydrodechlorination of 12-dichloropropaneeffect of preparation condition ofmesoporous aluminardquo Journal

of Molecular Catalysis A Chemical vol 219 no 1 pp 87ndash952004

[74] I Mora-Barrantes A Rodrıguez L Ibarra L Gonzalez and JL Valentın ldquoOvercoming the disadvantages of fumed silica asfiller in elastomer compositesrdquo Journal of Materials Chemistryvol 21 no 20 pp 7381ndash7392 2011

[75] G Perot and M Guisnet ldquoAdvantages and disadvantages ofzeolites as catalysts in organic chemistryrdquo Journal of MolecularCatalysis vol 61 no 2 pp 173ndash196 1990

[76] A Nezamzadeh-Ejhieh and S Khorsandi ldquoPhotocatalyticdegradation of 4-nitrophenol with ZnO supported nano-clinoptilolite zeoliterdquo Journal of Industrial and EngineeringChemistry vol 20 no 3 pp 937ndash946 2014

[77] A-N A El-Hendawy ldquoSurface and adsorptive properties ofcarbons prepared from biomassrdquo Applied Surface Science vol252 no 2 pp 287ndash295 2005

[78] Z Z Chowdhury S B A Hamid R Das et al ldquoPreparationof carbonaceous adsorbents from lignocellulosic biomass andtheir use in removal of contaminants from aqueous solutionrdquoBioResources vol 8 no 4 pp 6523ndash6555 2013

[79] I V Delidovich B LMoroz O P Taran et al ldquoAerobic selectiveoxidation of glucose to gluconate catalyzed by AuAl

2O3and

AuC impact of the mass-transfer processes on the overallkineticsrdquo Chemical Engineering Journal vol 223 pp 921ndash9312013

[80] H Zhang and N Toshima ldquoSynthesis of AuPt bimetallicnanoparticles with a Pt-rich shell and their high catalyticactivities for aerobic glucose oxidationrdquo Journal of Colloid andInterface Science vol 394 no 1 pp 166ndash176 2013

[81] L Wang D Yang J Wang Z Zhu and K Zhou ldquoAmbienttemperature COoxidation over gold nanoparticles (14 nm) sup-ported on Mg(OH)

2nanosheetsrdquo Catalysis Communications

vol 36 pp 38ndash42 2013[82] V G Milt S Ivanova O Sanz et al ldquoAuTiO

2supported on

ferritic stainless steel monoliths as CO oxidation catalystsrdquoApplied Surface Science vol 270 pp 169ndash177 2013

[83] S Rohe K Frank A Schaefer et al ldquoCO oxidation onnanoporous gold a combined TPD and XPS study of activecatalystsrdquo Surface Science vol 609 pp 106ndash112 2013

[84] X Huang XWang XWang et al ldquoP123-stabilized Au-Ag alloynanoparticles for kinetics of aerobic oxidation of benzyl alcoholin aqueous solutionrdquo Journal of Catalysis vol 301 pp 217ndash2262013

[85] H Wang W Fan Y He J Wang J N Kondo and T TatsumildquoSelective oxidation of alcohols to aldehydesketones overcopper oxide-supported gold catalystsrdquo Journal of Catalysis vol299 pp 10ndash19 2013

[86] M J Beier B Schimmoeller T W Hansen J E T AndersenS E Pratsinis and J-D Grunwaldt ldquoSelective side-chainoxidation of alkyl aromatic compounds catalyzed by ceriummodified silver catalystsrdquo Journal of Molecular Catalysis AChemical vol 331 no 1-2 pp 40ndash49 2010

[87] XWang B Tang XHuang YMa andZ Zhang ldquoHigh activityof novel nanoporous Pd-Au catalyst for methanol electro-oxidation in alkaline mediardquo Journal of Alloys and Compoundsvol 565 pp 120ndash126 2013

[88] K Kahler M C Holz M Rohe A C van Veen and MMuhler ldquoMethanol oxidation as probe reaction for active sitesinAuZnO andAuTiO

2catalystsrdquo Journal of Catalysis vol 299

pp 162ndash170 2013


[89] G Zhao M Deng Y Jiang H Hu J Huang and Y LuldquoMicrostructured AuNi-fiber catalyst Galvanic reaction prep-aration and catalytic performance for low-temperature gas-phase alcohol oxidationrdquo Journal of Catalysis vol 301 pp 46ndash53 2013

[90] X Bokhimi R Zanella V Maturano and A Morales ldquoNano-crystalline Ag and Au-Ag alloys supported on titania for COoxidation reactionrdquo Materials Chemistry and Physics vol 138no 2-3 pp 490ndash499 2013

[91] Q Ye J Zhao F Huo et al ldquoNanosized Au supported on three-dimensionally ordered mesoporous 120573-MnO

2 highly active cat-

alysts for the low-temperature oxidation of carbon monoxidebenzene and toluenerdquoMicroporous and Mesoporous Materialsvol 172 pp 20ndash29 2013

[92] L Li A Wang B Qiao et al ldquoOrigin of the high activity ofAuFeO

119909for low-temperatureCOoxidation direct evidence for

a redox mechanismrdquo Journal of Catalysis vol 299 pp 90ndash1002013

[93] P R Makgwane and S S Ray ldquoNanosized ruthenium particlesdecorated carbon nanofibers as active catalysts for the oxidationof p-cymene by molecular oxygenrdquo Journal of Molecular Catal-ysis A Chemical vol 373 pp 1ndash11 2013

[94] M Zhang X Zhu X Liang and Z Wang ldquoPreparation ofhighly efficient AuC catalysts for glucose oxidation via novelplasma reductionrdquo Catalysis Communications vol 25 pp 92ndash95 2012

[95] P Bujak P Bartczak and J Polanski ldquoHighly efficient room-temperature oxidation of cyclohexene and d-glucose overnanogold AuSiO

2in waterrdquo Journal of Catalysis vol 295 pp

15ndash21 2012[96] A C Sunil Sekhar K Sivaranjani C S Gopinath and C P

Vinod ldquoA simple one pot synthesis of nano gold-mesoporoussilica and its oxidation catalysisrdquo Catalysis Today vol 198 no 1pp 92ndash97 2012

[97] G Zhan Y Hong V T Mbah et al ldquoBimetallic Au-PdMgOas efficient catalysts for aerobic oxidation of benzyl alcohol agreen bio-reducing preparation methodrdquo Applied Catalysis AGeneral vol 439-440 pp 179ndash186 2012

[98] T Yan DW RedmanW-Y Yu DW Flaherty J A Rodriguezand C B Mullins ldquoCO oxidation on inverse Fe

2O3Au(1 1 1)

model catalystsrdquo Journal of Catalysis vol 294 pp 216ndash222 2012[99] W Li A Wang X Liu and T Zhang ldquoSilica-supported Au-Cu

alloy nanoparticles as an efficient catalyst for selective oxidationof alcoholsrdquoApplied Catalysis A General vol 433-434 pp 146ndash151 2012

[100] V V Costa M Estrada Y Demidova et al ldquoGold nanoparticlessupported on magnesium oxide as catalysts for the aerobicoxidation of alcohols under alkali-free conditionsrdquo Journal ofCatalysis vol 292 pp 148ndash156 2012

[101] J C Bauer G M Veith L F Allard Y Oyola S H Overburyand S Dai ldquoSilica-supported Au-CuO

119909hybrid nanocrystals as

active and selective catalysts for the formation of acetaldehydefrom the oxidation of ethanolrdquo ACS Catalysis vol 2 no 12 pp2537ndash2546 2012

[102] R Saliger N Decker and U Pruszlige ldquoD-Glucose oxidationwith H

2O2on an AuAl

2O3catalystrdquo Applied Catalysis B

Environmental vol 102 no 3-4 pp 584ndash589 2011[103] S Hermans A Deffernez and M Devillers ldquoAu-PdC catalysts

for glyoxal and glucose selective oxidationsrdquo Applied CatalysisA General vol 395 no 1-2 pp 19ndash27 2011

[104] I Witonska M Frajtak and S Karski ldquoSelective oxidation ofglucose to gluconic acid over Pd-Te supported catalystsrdquoAppliedCatalysis A General vol 401 no 1-2 pp 73ndash82 2011

[105] P Wu P Bai Z Lei K P Loh and X S Zhao ldquoGoldnanoparticles supported on functionalized mesoporous silicafor selective oxidation of cyclohexanerdquoMicroporous and Meso-porous Materials vol 141 no 1ndash3 pp 222ndash230 2011

[106] L Hu X Cao J Yang et al ldquoOxidation of benzylic compoundsby gold nanowires at 1 atm O

2rdquo Chemical Communications vol

47 no 4 pp 1303ndash1305 2011[107] H Aliyan R Fazaeli A R Massah H J Naghash and

S Moradi ldquoOxidation of benzylic alcohols with molecularoxygen catalyzed by Cu

32[PMO

12O40]SiO

2rdquo Iranian Journal

of Catalysis vol 1 no 1 pp 19ndash23 2011[108] M Rosu and A Schumpe ldquoOxidation of glucose in suspensions

of moderately hydrophobized palladium catalystsrdquo ChemicalEngineering Science vol 65 no 1 pp 220ndash225 2010

[109] T Benko A Beck O Geszti et al ldquoSelective oxidation ofglucose versus CO oxidation over supported gold catalystsrdquoApplied Catalysis A General vol 388 no 1-2 pp 31ndash36 2010

[110] M Chun Yan Z Mu J J Li et al ldquoMesoporous co3o4and

AUCO3o4catalysts for low-temperature oxidation of trace

ethylenerdquo Journal of the American Chemical Society vol 132 no8 pp 2608ndash2613 2010

[111] H Liu Y Liu Y Li Z Tang and H Jiang ldquoMetal-organicframework supported gold nanoparticles as a highly active het-erogeneous catalyst for aerobic oxidation of alcoholsrdquo Journal ofPhysical Chemistry C vol 114 no 31 pp 13362ndash13369 2010

[112] F Diehl J Barbier Jr D Duprez I Guibard and G MabilonldquoCatalytic oxidation of heavy hydrocarbons over PtAl

2O3

Influence of the structure of the molecule on its reactivityrdquoApplied Catalysis B Environmental vol 95 no 3-4 pp 217ndash2272010

[113] X Yang XWang C Liang et al ldquoAerobic oxidation of alcoholsoverAuTiO

2 an insight on the promotion effect of water on the

catalytic activity of AuTiO2rdquo Catalysis Communications vol 9

no 13 pp 2278ndash2281 2008[114] Q Jiang Y Xiao Z Tan Q-H Li and C-C Guo ldquoAerobic

oxidation of p-xylene overmetalloporphyrin and cobalt acetatetheir synergy andmechanismrdquo Journal ofMolecular Catalysis AChemical vol 285 no 1-2 pp 162ndash168 2008

[115] H Li B Guan W Wang et al ldquoAerobic oxidation of alcohol inaqueous solution catalyzed by goldrdquoTetrahedron vol 63 no 35pp 8430ndash8434 2007

[116] K M Parida and D Rath ldquoStructural properties and catalyticoxidation of benzene to phenol over CuO-impregnated meso-porous silicardquo Applied Catalysis A General vol 321 no 2 pp101ndash108 2007

[117] T Hayashi T Inagaki N Itayama and H Baba ldquoSelective oxi-dation of alcohol over supported gold catalystsmethyl glycolateformation from ethylene glycol andmethanolrdquo Catalysis Todayvol 117 no 1ndash3 pp 210ndash213 2006

[118] A C Gluhoi N Bogdanchikova and B E Nieuwenhuys ldquoTotaloxidation of propene and propane over gold-copper oxide onalumina catalysts comparison with PtAl

2O3rdquo Catalysis Today

vol 113 no 3-4 pp 178ndash181 2006[119] S Vetrivel and A Pandurangan ldquoAerial oxidation of p-

isopropyltoluene over manganese containing mesoporousMCM-41 and Al-MCM-41 molecular sievesrdquo Journal ofMolecular Catalysis A Chemical vol 246 no 1-2 pp 223ndash2302006


[120] B Guan D Xing G Cai et al ldquoHighly selective aerobicoxidation of alcohol catalyzed by a Gold(I) complex with ananionic ligandrdquo Journal of the American Chemical Society vol127 no 51 pp 18004ndash18005 2005

[121] K Zhu J Hu and R Richards ldquoAerobic oxidation of cyclo-hexane by gold nanoparticles immobilized upon mesoporoussilicardquo Catalysis Letters vol 100 no 3-4 pp 195ndash199 2005

[122] E J M Hensen Q Zhu R A J Janssen P C M M MagusinP J Kooyman and R A Van Santen ldquoSelective oxidation ofbenzene to phenol with nitrous oxide over MFI zeolites 1 onthe role of iron and aluminumrdquo Journal of Catalysis vol 233no 1 pp 123ndash135 2005

[123] R Zhang Z Qin M Dong G Wang and J Wang ldquoSelectiveoxidation of cyclohexane in supercritical carbon dioxide overCoAPO-5 molecular sievesrdquo Catalysis Today vol 110 no 3-4pp 351ndash356 2005

[124] Y Onal S Schimpf and P Claus ldquoStructure sensitivity andkinetics of D-glucose oxidation toD-gluconic acid over carbon-supported gold catalystsrdquo Journal of Catalysis vol 223 no 1 pp122ndash133 2004

[125] M Kang M W Song and C H Lee ldquoCatalytic carbonmonoxide oxidation over CoO

119909CeO

2composite catalystsrdquo

Applied Catalysis A General vol 251 no 1 pp 143ndash156 2003[126] S Biella L Prati and M Rossi ldquoSelective oxidation of D-

glucose on gold catalystrdquo Journal of Catalysis vol 206 no 2pp 242ndash247 2002

[127] S Xiang Y Zhang Q Xin and C Li ldquoEnantioselective epoxi-dation of olefins catalyzed by Mn (salen)MCM-41 synthesizedwith a new anchoring methodrdquo Chemical Communications no22 pp 2696ndash2697 2002

[128] B Skarman D Grandjean R E Benfield A Hinz A Anders-son and L ReineWallenberg ldquoCarbon monoxide oxidation onnanostructured CuO

119909CeO

2composite particles characterized

by HREM XPS XAS and high-energy diffractionrdquo Journal ofCatalysis vol 211 no 1 pp 119ndash133 2002

[129] G Mul A Zwijnenburg B van der Linden M Makkeeand J A Moulijn ldquoStability and selectivity of AuTiO

2and

AuTiO2SiO2catalysts in propene epoxidation an in situFT-IR

studyrdquo Journal of Catalysis vol 201 no 1 pp 128ndash137 2001[130] E E Stangland K B Stavens R P Andres and W N Delgass

ldquoCharacterization of gold-titania catalysts via oxidation ofpropylene to propylene oxiderdquo Journal of Catalysis vol 191 no2 pp 332ndash347 2000

[131] T A Nijhuis B J Huizinga M Makkee and J A MoulijnldquoDirect epoxidation of propene using gold dispersed on TS-1and other titanium-containing supportsrdquo Industrial and Engi-neering Chemistry Research vol 38 no 3 pp 884ndash891 1999

[132] Y Matsumoto M Asami M Hashimoto and M MisonoldquoAlkane oxidation with mixed addenda heteropoly catalystscontaining Ru(III) and Rh(III)rdquo Journal of Molecular CatalysisA Chemical vol 114 no 1ndash3 pp 161ndash168 1996

[133] F Boccuzzi A Chiorino S Tsubota and M Haruta ldquoFTIRstudy of carbon monoxide oxidation and scrambling at roomtemperature over gold supported on ZnO and TiO

2sdot 2rdquo Journal

of Physical Chemistry vol 100 no 9 pp 3625ndash3631 1996[134] M A Bollinger and M A Vannice ldquoA kinetic and DRIFTS

study of low-temperature carbon monoxide oxidation over Au-TiO2catalystsrdquoApplied Catalysis B Environmental vol 8 no 4

pp 417ndash443 1996[135] S Furukawa Y Hitomi T Shishido and T Tanaka ldquoEfficient

aerobic oxidation of hydrocarbons promoted by high-spin

nonheme Fe(II) complexes without any reductantrdquo InorganicaChimica Acta vol 378 no 1 pp 19ndash23 2011

[136] L-F Gutierrez S Hamoudi and K Belkacemi ldquoSynthesis ofgold catalysts supported on mesoporous silica materials recentdevelopmentsrdquo Catalysts vol 1 no 1 pp 97ndash154 2011

[137] A Hugon N E Kolli and C Louis ldquoAdvances in the prepara-tion of supported gold catalysts mechanism of deposition sim-plification of the procedures and relevance of the elimination ofchlorinerdquo Journal of Catalysis vol 274 no 2 pp 239ndash250 2010

[138] W R Glomm G Oslashye J Walmsley and J Sjoblom ldquoSyn-thesis and characterization of gold nanoparticle-functionalizedordered mesoporous materialsrdquo Journal of Dispersion Scienceand Technology vol 26 no 6 pp 729ndash744 2005

[139] R Zanella S Giorgio C R Henry and C Louis ldquoAlternativemethods for the preparation of gold nanoparticles supported onTiO2rdquo Journal of Physical Chemistry B vol 106 no 31 pp 7634ndash

7642 2002[140] D A Sverjensky and K Fukushi ldquoAnion adsorption on oxide

surfaces inclusion of the water dipole in modeling the electro-statics of ligand exchangerdquoEnvironmental ScienceampTechnologyvol 40 no 1 pp 263ndash271 2006

[141] R Zanella L Delannoy and C Louis ldquoMechanism of depo-sition of gold precursors onto TiO

2during the preparation by

cation adsorption and deposition-precipitationwithNaOH andureardquo Applied Catalysis A General vol 291 no 1-2 pp 62ndash722005

[142] M Okumura S Nakamura S Tsubota T Nakamura MAzuma and M Haruta ldquoChemical vapor deposition of goldon Al

2O3 SiO2 and TiO

2for the oxidation of CO and of H

2rdquo

Catalysis Letters vol 51 no 3-4 pp 53ndash58 1998[143] Y-S Chi H-P Lin and C-Y Mou ldquoCO oxidation over gold

nanocatalyst confined in mesoporous silicardquo Applied CatalysisA General vol 284 no 1-2 pp 199ndash206 2005

[144] J Lee J C Park and H Song ldquoA Nanoreactor framework ofa AuSiO

2yolkshell structure for catalytic reduction of p-

nitrophenolrdquo Advanced Materials vol 20 no 8 pp 1523ndash15282008

[145] D T Thompson ldquoAn overview of gold-catalysed oxidationprocessesrdquo Topics in Catalysis vol 38 no 4 pp 231ndash240 2006

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of



CeramicsJournal of


CompositesJournal of

NanoparticlesJournal of



International Journal of

Biomaterials


NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014


CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research



MetallurgyJournal of


BioMed Research International

MaterialsJournal of


Nano

materials


Journal ofNanomaterials


Table 1 Major features advantages and disadvantages of the commonly used support materials

Supports materials Features Advantages Disadvantages References

Alumina

(1) Hardness(2) High melting point andhigh compression strength(3) Resistant to abrasionand chemical attack(4) High thermalconductivity

(1) Thermally stable(2) Randomly ordered(3) High surface area andpore volume(4) Well-ordered pore(5) Narrow pore size

(1) Difficult to control thehydrolysis rate ofaluminum precursors

[73]

Silica

(1) Tendency to form largenetworks(2) Found in nature andliving organisms(3) Hardness

(1) High efficiency(2) High selectivity(3) Highly stable(4) Mechanical strength

(1) Low compatibility(2) Formation ofaggregatesagglomerates

[74]

Zeolite(1) Microporous(2) Inertness(3) Excellent electronconductivity

(1) Highly effective(2) Less or no corrosion(3) No waste or disposalproblems(4) High thermo stability(5) Easy set-up ofcontinuous processes(6) Great adaptability topractically all types ofcatalysis

(1) Irreversible adsorptionor steric blockage of heavysecondary products(2) Impossibility of usingmicroporosity(3) Difficult to exploit theshape selectivity

[75 76]

Carbon(1) Nonmetallic(2) Tetravalent(3) Porous structure

(1) High mechanicalstrength(2) Large surface area(3) Excellent electronconductivity(4) Good elasticity(5) Thermal stability(6) Inertness

(1) High temperaturephysical activation(2) Expensive(3) Emission of greenhousegasses during pyrolysis

[77 78]

and reproducibility to catalyze the reaction under mild con-ditions The single catalytic entity in homogeneous catalystscan act as a single active site which can speed up reaction andreduce the reaction time [18] However homogeneous cat-alytic processes produce huge waste materials significantlydisrupting the environmental and ecological stability [19ndash21]One of the main disadvantages to the use of these types ofcatalysts is the ease of separating of the comparatively affluentcatalysts from the reaction mixtures at the end of reaction[9 19 22] Homogeneous catalysts also cause corrosion tothe industrial materials and some of them are deposited onthe reactor wall To get rid of these problems and minimizeenvironmental hazards the homogenous catalysts could beprepared by the dispersion of metal on an insoluble solidsupports via covalent anchoring to keep the metal on thesurface where catalysis reaction takes place [18 22]

Heterogeneous catalyst is considered to be a better choicefor the synthesis of commodity materials [23ndash25] Nowadayssilica carbon clay zeolite metal oxide polymers and othermesoporous materials are being used as inorganic solidsupports [26 27] Supported materials can be obtained ascomplexes with transition metals and Schiff base ligandsby heterogenization process [28] The application of sup-ported polymers in catalytic oxidation has gained muchattention because of their inertness and nontoxic nonvolatileand recyclable criteria [29] Among inorganic supports

the mesoporous materials have been proven to be idealcatalyst supports due to their three-dimensional open porenetwork structures high surface area and porosity highreusability and heat stability and uniform and interconnectedpores which offer a reliable and well-separated atmospherefor the deposition of dynamic components and interactivesurfaces between the catalysts and reactants [30ndash38] Varioussupport materials along with their major features are pre-sented in Table 1

Heterogeneous catalysts promote oxidation reactions viaattracting oxygen fromoxidants such as TBHP (tert-BuO

2H)

and HP (H2O2) [39 40] In the last decade TBHP has been

used as oxidant for various oxidation reactions such as alkylbenzene and benzyl alcohol oxidation In this review wedescribed heterogeneous catalysts their synthesis schemeson various supports and applications in selected oxidationreactions The comparative features of homogeneous andheterogeneous catalysts are presented in Figure 1

2 Heterogeneous Catalysts

In heterogeneous catalysis reaction the catalysts and reac-tants exist in different phases In reality the vast majority ofheterogeneous catalysts are solids and the vast majority ofreactants are either gases or liquids [14] A phase separationcatalysis reaction greatly helps in reactant product and


Disadvantages

Advantages

Major features

Homogeneous

Major features

Catalysts

Heterogeneous

Advantages

Disadvantages









(2) Co dissolved


(4) Easy separation













Table2Re

cent

scenario

inheterogeneou

scatalysis

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2013

Fenano

catalyst

Immob

ilizatio


benzylalcoho

loxidation

[18]

2013

AuA

l 2O3Au

CDeposition

-precipitatio

ncatio

nica

dsorption

Glucose

oxidation

[79]

2013

AuPtb

imetallic

nano

particles

mdashGlucose

oxidation

[80]

2013

Goldnano

particles

supp

ortedon

Mg(OH) 2nano

sheets

Colloidaldepo

sition

COoxidation

[81]

2013

AuTiO

2supp

ortedon

ferritics

tainles

sste

elmon

olith

sDire

ctanionice

xchange

COoxidation

[82]

2013

Nanop

orou

sgold

Electro

lytic

dissolution

COoxidation

[83]

2013

P123-stabilized

Au-Agalloy

Coredu

ction

Benzylalcoho

loxidatio

n[84]

2013

Alumina-supp

ortedgold-ruthenium

bimetallic

catalysts

Incipientw

etnessIm

pregnatio

nDeposition

Precipitatio

nCO

oxidation

[54]

2013

AuCuO

catalysts

Cop

recipitatio

nAlcoh

oloxidation

[85]

2013

Cerium

mod

ified

silver

Impregnatio

nAlkylarom

aticcompo

unds

[86]

2013

Pd-Aucatalyst

Deallo

ying

Methano

lelectrooxidation

[87]

2013

AuZnO

andAu

TiO

2catalysts

Colloidaldepo

sition

Methano

loxidatio

n[88]

2013

Microstructured

AuN

i-fiberc

atalyst


gAlcoh

oloxidation

[89]

2013

Nanocrystallin

eAgandAu

-Agalloys

supp

ortedon

titania

Deposition

Precipitatio

nCO

oxidation

[90]

2013

Nanosized

Ausupp

ortedon

3-Dordered

mesop

orou

sMnO

2

Deposition

Precipitatio

nOxidatio

nof

carbon

mon


[91]

2013

AuFeO119909

Cop

recipitatio

nCO

oxidation

[92]

2013

Nanosized

ruthenium

particlesd

ecorated

carbon

nano

fibers

Solgel

p-Cy

meneo

xidatio

n[93]

2012

AuC

Incipientw

etness

impregnatio

nGlucose

oxidation

[94]

2012

CeA

lPO-5

molecular

sieves

mdashDiphenylm

ethane

oxidation

[10]

2012

Nanosized

gold

onSiO

2Stob

erCy

clohexene

andD-glucose

oxidation

[95]

2012

AuSiO

2Disp

ersio

nSilaneso

xidatio

n[47]

2012

Nanogold-m

esop

orou

ssilica

mdashCO

oxidation

benzylalcoho

loxidatio

n[96]

2012

Nanosized

gold

Disp

ersio

nAlkylbenzeneo

xidatio

n[40]

2012

AgSB

A-15

Impregnatio

nAlkylsubstituted

arom

atics

[35]

2012

Bimetallic

Au-PdMgO

Sol-immob

ilizatio

n(SI)and

adsorptio

n-redu

ction(A

R)Be

nzylalcoho

loxidatio

n[97]


Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2012

InverseF

e 2O

3Au

(111)m

odelcatalysts

mdashCO

oxidation

[98]

2012

Silica-supp

ortedAu

-Cualloy

mdashAlcoh

oloxidation

[99]

2012

Goldnano

particlessup

ported

onMgO

Deposition

-precipitatio

nAlcoh

oloxidation

[100]

2012

Silica-supp

ortedAu

-CuO119909

Oxidativ

edeallo

ying

Ethano

loxidatio

n[101]

2011

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

oxidation

[102]

2011

Au-PdC

Impregnatio

nGlyoxalandglucoseo

xidatio

n[103]

2011

Pd-Tes

uppo

rted

catalysts

Repeated

impregnatio

nGlucose

oxidation

[104]

2011

Goldnano

particlessup

ported

onfunctio

nalized

mesop

orou

ssilica

One-pot

Synthesis

Cyclo

hexane

oxidation

[105]

2011

Silicas

uppo

rted


Immob

ilizatio

nAlkylbenzeneo

xidatio

n[70]

2011

Goldnano

wire

smdash

Oxidatio

nof

benzyliccompo

unds

[106]

2011

Cu32[PM

o 12O

40]SiO

2Incipientw

etness

impregnatio

nBe

nzylicalcoho

l[107]

2010

Goldnano

particlesd

epositedon

cellu

lose

Deposition

-reductio

ngrinding

metho

dGlucose

oxidation

[41]

2010

Metallopo

rphyrin

boun

dto

silica

Immob

ilizatio

nEthylbenzene

oxidation

[68]

2010

Hydroph

obized

palladium

Vapo

rdeposition

Glucose

oxidation

[108]

2010

Supp

ortedgold

catalysts

Colloidalgold

depo

sition

COoxidation

[109]

2010

AuH

MScatalysts

Impregnatio

nanddirect

synthesis

Benzylalcoho

loxidatio

n[63]

2010

Mob

ilizedgold

nano

particles

Goldsol

Second

aryalcoho

lsoxidation

[67]

2010

Mesop

orou

sCo 3O

4andAu

Co 3O

4catalysts

Nanocastin

gEthylene

oxidation

[110]

2010

Metal-organicfram

eworksupp

ortedgold

nano

particles

Colloidaldepo

sition

Alcoh

oloxidation

[111]

2010

PtA

l 2O3

Impregnatio

nHeavy

hydrocarbo

nsoxidation

[112]

2009

AuTiO

2Deposition

-precipitatio

nAlcoh

oloxidation

[113]

2009

Co(Ac

O) 2M

n(Ac

O) 2

Dire

ctcond

ensatio

np-xylene

oxidation

[114]


Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2009

Nickelsub

stitutedcopp

erchromite

spinels

Cop

recipitatio

nAlkylsubstituted

benzeneo

xidatio

n[9]

2007

Goldcatalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[115]

2007

MCM

-48molecular

sieve

mod

ified

with

SnCl

2Po

st-synthesis

mod

ificatio

nAlcoh

oloxidation

[65]

2007

CuO-im

pregnatedmesop

orou

ssilica

Impregnatio

nBe

nzeneo

xidatio

n[116]

2006

Supp

ortedgold

catalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[117]

2006

Au-C

uOA

l 2O3PtA

l 2O3catalysts

Deposition

-precipitatio

nim

pregnatio

nProp

enea

ndprop

aneo

xidatio

n[118]

2006

Manganese

containing

mesop

orou

sMCM

-41and

Al-M

CM-41

molecular

sieves

Impregnatio

np-iso

prop

yltolueneo

xidatio

n[119]

2005

Goldcatalysts

mdashAlcoh

oloxidation

[120]

2005

AuC

Immob

ilizatio

nGlucose

oxidation

Alcoh

oloxidation

[64]

2005

Goldim

mob

ilizedmesop

orou

ssilica

Immob

ilizatio

nCy

clohexane

oxidation

[121]

2005

Nitrou

soxide

over

MFI

zeolites

Hydrothermal

Benzeneo

xidatio

n[122]

2005

CoA

PO-5

molecular

sieves

Hydrothermal

Cyclo

hexane

oxidation

[123]

2004

Carbon

-sup

ported

gold

Goldsol

Glucose

oxidation

[124]

2004

Mn-containing

MCM

-41

Impregnatio

nEthylbenzene

oxidation

[72]

2003

CoO119909C

eO2

Cop

recipitaion

Carbon

mon

oxideo

xidatio

n[125]

2002

Goldcatalysts

Immob

ilizatio

nGlucose

oxidation

[126]

2002

Mn(Salen)MCM

-41

mdashOlefin

sepo

xidatio

n[127]

2002

NanostructuredCu

O119909C

eO2

Gas-con

densation

Carbon

mon

oxideo

xidatio

n[128]

2002

Nano-Au

Catalysts

mdashCa

rbon

mon

oxideo

xidatio

n[55]

2001

AuTiO

2Au

TiO

2SiO

2Deposition

-precipitatio

nProp

enee

poxidatio

n[129]

2000


Deposition

-precipitatio

nProp

yleneo

xidatio

n[130]

1999

Golddispersedon

TS1and

other

titanium-con

tainingsupp

orts

Disp

ersio

nProp

enee

poxidatio

n[131]

1998


Deposition

-precipitatio

nProp

ylenee

poxidatio

n[61]

1996

Heterop

olycatalysts

containing

Ru(III)

andRh

(III)p

articles

mdashAlkaneo

xidatio

n[132]

1996

Goldsupp

ortedon

ZnOandTiO

2Cop

recipitatio

namp

Deposition

-precipitatio

nCa

rbon

mon

oxideo

xidatio

n[133]

1996

Au-TiO

2Incipientw

etness

impregnatio

nCa

rbon

mon

oxideo

xidatio

n[134]

1995

Bism

uthprom

oted

palladium

catalysts

Ionexchange

Glucose

oxidation

[42]


HO HO

OOH

OHOH

OH OH

OHOH

OH

OH O


Catalysts


Si

ClCl Cl

H


Si CH3

CH3

CH3

Si CH3

CH3

CH3

H3C

Scheme 1

H OH


THF RTSi Si

CH3

CH3 CH3

CH3

+ H2O + H2

AuSiO2

Scheme 2



2O3and ZrO








3)4) (Scheme 1)




Table3Oxidatio

nof

glucoseb

yvario

uscatalysts

Nam

eofcatalysts

Preparationmetho

dRe

actio

ncond

ition

Mainprod

uct

Selectivity

()Re

ferences

SubstrateOxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)

pHSolvent

Goldnano

particleso

ncellu

lose

Deposition

-redu

ction

O2

mdash60

95Water

Gluconica

cid

mdash[41]

AuA

l 2O3

Deposition

-precipitatio

nO

27

6090

Water

Gluconica

cid

97[79]

AuC

Catio

nica

dsorption

O2

760

90Water

Gluconica

cid

97[79]

Au-PdC

Impregnatio

nO

220

5092

5mdash

Gluconica

cid

mdash[103]

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

H2O

240

90mdash

Sodium

D-gluconate

99[102]

AuC

Goldsol

mdash30

5095

mdashGluconica

cid

45[124]

Nanosized

AuSiO

2Stob

erH

2O2

2430

92Water

Gluconica

cid

80[95]

Pb-TeSiO

2Re

peated

impregnatio

nO

215

6090

mdashGluconica

cid

884

[104]

AuPtb

imetallic

nano

particle

Vacuum

drying

O2

260

95mdash

Gluconica

cid

mdash[80]




AuSiO2

Triethylsilane


Catalyst

Decomposition

H2 + O2 H2O2

2H2O2

H2O + 12O2

Hydrogenation H2








2O3








2O2from H

2and




2O2conversion




SiO2







2O2[53]





3NO3or Au

9L8(NO3)3 L = PPh

3) onto


4



C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus


2


O

Catalysts

Propene epoxide









Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




Disadvantages

Advantages

Major features

Homogeneous

Major features

Catalysts

Heterogeneous

Advantages

Disadvantages









(2) Co dissolved


(4) Easy separation













Table2Re

cent

scenario

inheterogeneou

scatalysis

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2013

Fenano

catalyst

Immob

ilizatio


benzylalcoho

loxidation

[18]

2013

AuA

l 2O3Au

CDeposition

-precipitatio

ncatio

nica

dsorption

Glucose

oxidation

[79]

2013

AuPtb

imetallic

nano

particles

mdashGlucose

oxidation

[80]

2013

Goldnano

particles

supp

ortedon

Mg(OH) 2nano

sheets

Colloidaldepo

sition

COoxidation

[81]

2013

AuTiO

2supp

ortedon

ferritics

tainles

sste

elmon

olith

sDire

ctanionice

xchange

COoxidation

[82]

2013

Nanop

orou

sgold

Electro

lytic

dissolution

COoxidation

[83]

2013

P123-stabilized

Au-Agalloy

Coredu

ction

Benzylalcoho

loxidatio

n[84]

2013

Alumina-supp

ortedgold-ruthenium

bimetallic

catalysts

Incipientw

etnessIm

pregnatio

nDeposition

Precipitatio

nCO

oxidation

[54]

2013

AuCuO

catalysts

Cop

recipitatio

nAlcoh

oloxidation

[85]

2013

Cerium

mod

ified

silver

Impregnatio

nAlkylarom

aticcompo

unds

[86]

2013

Pd-Aucatalyst

Deallo

ying

Methano

lelectrooxidation

[87]

2013

AuZnO

andAu

TiO

2catalysts

Colloidaldepo

sition

Methano

loxidatio

n[88]

2013

Microstructured

AuN

i-fiberc

atalyst


gAlcoh

oloxidation

[89]

2013

Nanocrystallin

eAgandAu

-Agalloys

supp

ortedon

titania

Deposition

Precipitatio

nCO

oxidation

[90]

2013

Nanosized

Ausupp

ortedon

3-Dordered

mesop

orou

sMnO

2

Deposition

Precipitatio

nOxidatio

nof

carbon

mon


[91]

2013

AuFeO119909

Cop

recipitatio

nCO

oxidation

[92]

2013

Nanosized

ruthenium

particlesd

ecorated

carbon

nano

fibers

Solgel

p-Cy

meneo

xidatio

n[93]

2012

AuC

Incipientw

etness

impregnatio

nGlucose

oxidation

[94]

2012

CeA

lPO-5

molecular

sieves

mdashDiphenylm

ethane

oxidation

[10]

2012

Nanosized

gold

onSiO

2Stob

erCy

clohexene

andD-glucose

oxidation

[95]

2012

AuSiO

2Disp

ersio

nSilaneso

xidatio

n[47]

2012

Nanogold-m

esop

orou

ssilica

mdashCO

oxidation

benzylalcoho

loxidatio

n[96]

2012

Nanosized

gold

Disp

ersio

nAlkylbenzeneo

xidatio

n[40]

2012

AgSB

A-15

Impregnatio

nAlkylsubstituted

arom

atics

[35]

2012

Bimetallic

Au-PdMgO

Sol-immob

ilizatio

n(SI)and

adsorptio

n-redu

ction(A

R)Be

nzylalcoho

loxidatio

n[97]


Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2012

InverseF

e 2O

3Au

(111)m

odelcatalysts

mdashCO

oxidation

[98]

2012

Silica-supp

ortedAu

-Cualloy

mdashAlcoh

oloxidation

[99]

2012

Goldnano

particlessup

ported

onMgO

Deposition

-precipitatio

nAlcoh

oloxidation

[100]

2012

Silica-supp

ortedAu

-CuO119909

Oxidativ

edeallo

ying

Ethano

loxidatio

n[101]

2011

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

oxidation

[102]

2011

Au-PdC

Impregnatio

nGlyoxalandglucoseo

xidatio

n[103]

2011

Pd-Tes

uppo

rted

catalysts

Repeated

impregnatio

nGlucose

oxidation

[104]

2011

Goldnano

particlessup

ported

onfunctio

nalized

mesop

orou

ssilica

One-pot

Synthesis

Cyclo

hexane

oxidation

[105]

2011

Silicas

uppo

rted


Immob

ilizatio

nAlkylbenzeneo

xidatio

n[70]

2011

Goldnano

wire

smdash

Oxidatio

nof

benzyliccompo

unds

[106]

2011

Cu32[PM

o 12O

40]SiO

2Incipientw

etness

impregnatio

nBe

nzylicalcoho

l[107]

2010

Goldnano

particlesd

epositedon

cellu

lose

Deposition

-reductio

ngrinding

metho

dGlucose

oxidation

[41]

2010

Metallopo

rphyrin

boun

dto

silica

Immob

ilizatio

nEthylbenzene

oxidation

[68]

2010

Hydroph

obized

palladium

Vapo

rdeposition

Glucose

oxidation

[108]

2010

Supp

ortedgold

catalysts

Colloidalgold

depo

sition

COoxidation

[109]

2010

AuH

MScatalysts

Impregnatio

nanddirect

synthesis

Benzylalcoho

loxidatio

n[63]

2010

Mob

ilizedgold

nano

particles

Goldsol

Second

aryalcoho

lsoxidation

[67]

2010

Mesop

orou

sCo 3O

4andAu

Co 3O

4catalysts

Nanocastin

gEthylene

oxidation

[110]

2010

Metal-organicfram

eworksupp

ortedgold

nano

particles

Colloidaldepo

sition

Alcoh

oloxidation

[111]

2010

PtA

l 2O3

Impregnatio

nHeavy

hydrocarbo

nsoxidation

[112]

2009

AuTiO

2Deposition

-precipitatio

nAlcoh

oloxidation

[113]

2009

Co(Ac

O) 2M

n(Ac

O) 2

Dire

ctcond

ensatio

np-xylene

oxidation

[114]


Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2009

Nickelsub

stitutedcopp

erchromite

spinels

Cop

recipitatio

nAlkylsubstituted

benzeneo

xidatio

n[9]

2007

Goldcatalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[115]

2007

MCM

-48molecular

sieve

mod

ified

with

SnCl

2Po

st-synthesis

mod

ificatio

nAlcoh

oloxidation

[65]

2007

CuO-im

pregnatedmesop

orou

ssilica

Impregnatio

nBe

nzeneo

xidatio

n[116]

2006

Supp

ortedgold

catalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[117]

2006

Au-C

uOA

l 2O3PtA

l 2O3catalysts

Deposition

-precipitatio

nim

pregnatio

nProp

enea

ndprop

aneo

xidatio

n[118]

2006

Manganese

containing

mesop

orou

sMCM

-41and

Al-M

CM-41

molecular

sieves

Impregnatio

np-iso

prop

yltolueneo

xidatio

n[119]

2005

Goldcatalysts

mdashAlcoh

oloxidation

[120]

2005

AuC

Immob

ilizatio

nGlucose

oxidation

Alcoh

oloxidation

[64]

2005

Goldim

mob

ilizedmesop

orou

ssilica

Immob

ilizatio

nCy

clohexane

oxidation

[121]

2005

Nitrou

soxide

over

MFI

zeolites

Hydrothermal

Benzeneo

xidatio

n[122]

2005

CoA

PO-5

molecular

sieves

Hydrothermal

Cyclo

hexane

oxidation

[123]

2004

Carbon

-sup

ported

gold

Goldsol

Glucose

oxidation

[124]

2004

Mn-containing

MCM

-41

Impregnatio

nEthylbenzene

oxidation

[72]

2003

CoO119909C

eO2

Cop

recipitaion

Carbon

mon

oxideo

xidatio

n[125]

2002

Goldcatalysts

Immob

ilizatio

nGlucose

oxidation

[126]

2002

Mn(Salen)MCM

-41

mdashOlefin

sepo

xidatio

n[127]

2002

NanostructuredCu

O119909C

eO2

Gas-con

densation

Carbon

mon

oxideo

xidatio

n[128]

2002

Nano-Au

Catalysts

mdashCa

rbon

mon

oxideo

xidatio

n[55]

2001

AuTiO

2Au

TiO

2SiO

2Deposition

-precipitatio

nProp

enee

poxidatio

n[129]

2000


Deposition

-precipitatio

nProp

yleneo

xidatio

n[130]

1999

Golddispersedon

TS1and

other

titanium-con

tainingsupp

orts

Disp

ersio

nProp

enee

poxidatio

n[131]

1998


Deposition

-precipitatio

nProp

ylenee

poxidatio

n[61]

1996

Heterop

olycatalysts

containing

Ru(III)

andRh

(III)p

articles

mdashAlkaneo

xidatio

n[132]

1996

Goldsupp

ortedon

ZnOandTiO

2Cop

recipitatio

namp

Deposition

-precipitatio

nCa

rbon

mon

oxideo

xidatio

n[133]

1996

Au-TiO

2Incipientw

etness

impregnatio

nCa

rbon

mon

oxideo

xidatio

n[134]

1995

Bism

uthprom

oted

palladium

catalysts

Ionexchange

Glucose

oxidation

[42]


HO HO

OOH

OHOH

OH OH

OHOH

OH

OH O


Catalysts


Si

ClCl Cl

H


Si CH3

CH3

CH3

Si CH3

CH3

CH3

H3C

Scheme 1

H OH


THF RTSi Si

CH3

CH3 CH3

CH3

+ H2O + H2

AuSiO2

Scheme 2



2O3and ZrO








3)4) (Scheme 1)




Table3Oxidatio

nof

glucoseb

yvario

uscatalysts

Nam

eofcatalysts

Preparationmetho

dRe

actio

ncond

ition

Mainprod

uct

Selectivity

()Re

ferences

SubstrateOxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)

pHSolvent

Goldnano

particleso

ncellu

lose

Deposition

-redu

ction

O2

mdash60

95Water

Gluconica

cid

mdash[41]

AuA

l 2O3

Deposition

-precipitatio

nO

27

6090

Water

Gluconica

cid

97[79]

AuC

Catio

nica

dsorption

O2

760

90Water

Gluconica

cid

97[79]

Au-PdC

Impregnatio

nO

220

5092

5mdash

Gluconica

cid

mdash[103]

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

H2O

240

90mdash

Sodium

D-gluconate

99[102]

AuC

Goldsol

mdash30

5095

mdashGluconica

cid

45[124]

Nanosized

AuSiO

2Stob

erH

2O2

2430

92Water

Gluconica

cid

80[95]

Pb-TeSiO

2Re

peated

impregnatio

nO

215

6090

mdashGluconica

cid

884

[104]

AuPtb

imetallic

nano

particle

Vacuum

drying

O2

260

95mdash

Gluconica

cid

mdash[80]




AuSiO2

Triethylsilane


Catalyst

Decomposition

H2 + O2 H2O2

2H2O2

H2O + 12O2

Hydrogenation H2








2O3








2O2from H

2and




2O2conversion




SiO2







2O2[53]





3NO3or Au

9L8(NO3)3 L = PPh

3) onto


4



C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus


2


O

Catalysts

Propene epoxide









Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




Table2Re

cent

scenario

inheterogeneou

scatalysis

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2013

Fenano

catalyst

Immob

ilizatio


benzylalcoho

loxidation

[18]

2013

AuA

l 2O3Au

CDeposition

-precipitatio

ncatio

nica

dsorption

Glucose

oxidation

[79]

2013

AuPtb

imetallic

nano

particles

mdashGlucose

oxidation

[80]

2013

Goldnano

particles

supp

ortedon

Mg(OH) 2nano

sheets

Colloidaldepo

sition

COoxidation

[81]

2013

AuTiO

2supp

ortedon

ferritics

tainles

sste

elmon

olith

sDire

ctanionice

xchange

COoxidation

[82]

2013

Nanop

orou

sgold

Electro

lytic

dissolution

COoxidation

[83]

2013

P123-stabilized

Au-Agalloy

Coredu

ction

Benzylalcoho

loxidatio

n[84]

2013

Alumina-supp

ortedgold-ruthenium

bimetallic

catalysts

Incipientw

etnessIm

pregnatio

nDeposition

Precipitatio

nCO

oxidation

[54]

2013

AuCuO

catalysts

Cop

recipitatio

nAlcoh

oloxidation

[85]

2013

Cerium

mod

ified

silver

Impregnatio

nAlkylarom

aticcompo

unds

[86]

2013

Pd-Aucatalyst

Deallo

ying

Methano

lelectrooxidation

[87]

2013

AuZnO

andAu

TiO

2catalysts

Colloidaldepo

sition

Methano

loxidatio

n[88]

2013

Microstructured

AuN

i-fiberc

atalyst


gAlcoh

oloxidation

[89]

2013

Nanocrystallin

eAgandAu

-Agalloys

supp

ortedon

titania

Deposition

Precipitatio

nCO

oxidation

[90]

2013

Nanosized

Ausupp

ortedon

3-Dordered

mesop

orou

sMnO

2

Deposition

Precipitatio

nOxidatio

nof

carbon

mon


[91]

2013

AuFeO119909

Cop

recipitatio

nCO

oxidation

[92]

2013

Nanosized

ruthenium

particlesd

ecorated

carbon

nano

fibers

Solgel

p-Cy

meneo

xidatio

n[93]

2012

AuC

Incipientw

etness

impregnatio

nGlucose

oxidation

[94]

2012

CeA

lPO-5

molecular

sieves

mdashDiphenylm

ethane

oxidation

[10]

2012

Nanosized

gold

onSiO

2Stob

erCy

clohexene

andD-glucose

oxidation

[95]

2012

AuSiO

2Disp

ersio

nSilaneso

xidatio

n[47]

2012

Nanogold-m

esop

orou

ssilica

mdashCO

oxidation

benzylalcoho

loxidatio

n[96]

2012

Nanosized

gold

Disp

ersio

nAlkylbenzeneo

xidatio

n[40]

2012

AgSB

A-15

Impregnatio

nAlkylsubstituted

arom

atics

[35]

2012

Bimetallic

Au-PdMgO

Sol-immob

ilizatio

n(SI)and

adsorptio

n-redu

ction(A

R)Be

nzylalcoho

loxidatio

n[97]


Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2012

InverseF

e 2O

3Au

(111)m

odelcatalysts

mdashCO

oxidation

[98]

2012

Silica-supp

ortedAu

-Cualloy

mdashAlcoh

oloxidation

[99]

2012

Goldnano

particlessup

ported

onMgO

Deposition

-precipitatio

nAlcoh

oloxidation

[100]

2012

Silica-supp

ortedAu

-CuO119909

Oxidativ

edeallo

ying

Ethano

loxidatio

n[101]

2011

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

oxidation

[102]

2011

Au-PdC

Impregnatio

nGlyoxalandglucoseo

xidatio

n[103]

2011

Pd-Tes

uppo

rted

catalysts

Repeated

impregnatio

nGlucose

oxidation

[104]

2011

Goldnano

particlessup

ported

onfunctio

nalized

mesop

orou

ssilica

One-pot

Synthesis

Cyclo

hexane

oxidation

[105]

2011

Silicas

uppo

rted


Immob

ilizatio

nAlkylbenzeneo

xidatio

n[70]

2011

Goldnano

wire

smdash

Oxidatio

nof

benzyliccompo

unds

[106]

2011

Cu32[PM

o 12O

40]SiO

2Incipientw

etness

impregnatio

nBe

nzylicalcoho

l[107]

2010

Goldnano

particlesd

epositedon

cellu

lose

Deposition

-reductio

ngrinding

metho

dGlucose

oxidation

[41]

2010

Metallopo

rphyrin

boun

dto

silica

Immob

ilizatio

nEthylbenzene

oxidation

[68]

2010

Hydroph

obized

palladium

Vapo

rdeposition

Glucose

oxidation

[108]

2010

Supp

ortedgold

catalysts

Colloidalgold

depo

sition

COoxidation

[109]

2010

AuH

MScatalysts

Impregnatio

nanddirect

synthesis

Benzylalcoho

loxidatio

n[63]

2010

Mob

ilizedgold

nano

particles

Goldsol

Second

aryalcoho

lsoxidation

[67]

2010

Mesop

orou

sCo 3O

4andAu

Co 3O

4catalysts

Nanocastin

gEthylene

oxidation

[110]

2010

Metal-organicfram

eworksupp

ortedgold

nano

particles

Colloidaldepo

sition

Alcoh

oloxidation

[111]

2010

PtA

l 2O3

Impregnatio

nHeavy

hydrocarbo

nsoxidation

[112]

2009

AuTiO

2Deposition

-precipitatio

nAlcoh

oloxidation

[113]

2009

Co(Ac

O) 2M

n(Ac

O) 2

Dire

ctcond

ensatio

np-xylene

oxidation

[114]


Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2009

Nickelsub

stitutedcopp

erchromite

spinels

Cop

recipitatio

nAlkylsubstituted

benzeneo

xidatio

n[9]

2007

Goldcatalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[115]

2007

MCM

-48molecular

sieve

mod

ified

with

SnCl

2Po

st-synthesis

mod

ificatio

nAlcoh

oloxidation

[65]

2007

CuO-im

pregnatedmesop

orou

ssilica

Impregnatio

nBe

nzeneo

xidatio

n[116]

2006

Supp

ortedgold

catalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[117]

2006

Au-C

uOA

l 2O3PtA

l 2O3catalysts

Deposition

-precipitatio

nim

pregnatio

nProp

enea

ndprop

aneo

xidatio

n[118]

2006

Manganese

containing

mesop

orou

sMCM

-41and

Al-M

CM-41

molecular

sieves

Impregnatio

np-iso

prop

yltolueneo

xidatio

n[119]

2005

Goldcatalysts

mdashAlcoh

oloxidation

[120]

2005

AuC

Immob

ilizatio

nGlucose

oxidation

Alcoh

oloxidation

[64]

2005

Goldim

mob

ilizedmesop

orou

ssilica

Immob

ilizatio

nCy

clohexane

oxidation

[121]

2005

Nitrou

soxide

over

MFI

zeolites

Hydrothermal

Benzeneo

xidatio

n[122]

2005

CoA

PO-5

molecular

sieves

Hydrothermal

Cyclo

hexane

oxidation

[123]

2004

Carbon

-sup

ported

gold

Goldsol

Glucose

oxidation

[124]

2004

Mn-containing

MCM

-41

Impregnatio

nEthylbenzene

oxidation

[72]

2003

CoO119909C

eO2

Cop

recipitaion

Carbon

mon

oxideo

xidatio

n[125]

2002

Goldcatalysts

Immob

ilizatio

nGlucose

oxidation

[126]

2002

Mn(Salen)MCM

-41

mdashOlefin

sepo

xidatio

n[127]

2002

NanostructuredCu

O119909C

eO2

Gas-con

densation

Carbon

mon

oxideo

xidatio

n[128]

2002

Nano-Au

Catalysts

mdashCa

rbon

mon

oxideo

xidatio

n[55]

2001

AuTiO

2Au

TiO

2SiO

2Deposition

-precipitatio

nProp

enee

poxidatio

n[129]

2000


Deposition

-precipitatio

nProp

yleneo

xidatio

n[130]

1999

Golddispersedon

TS1and

other

titanium-con

tainingsupp

orts

Disp

ersio

nProp

enee

poxidatio

n[131]

1998


Deposition

-precipitatio

nProp

ylenee

poxidatio

n[61]

1996

Heterop

olycatalysts

containing

Ru(III)

andRh

(III)p

articles

mdashAlkaneo

xidatio

n[132]

1996

Goldsupp

ortedon

ZnOandTiO

2Cop

recipitatio

namp

Deposition

-precipitatio

nCa

rbon

mon

oxideo

xidatio

n[133]

1996

Au-TiO

2Incipientw

etness

impregnatio

nCa

rbon

mon

oxideo

xidatio

n[134]

1995

Bism

uthprom

oted

palladium

catalysts

Ionexchange

Glucose

oxidation

[42]


HO HO

OOH

OHOH

OH OH

OHOH

OH

OH O


Catalysts


Si

ClCl Cl

H


Si CH3

CH3

CH3

Si CH3

CH3

CH3

H3C

Scheme 1

H OH


THF RTSi Si

CH3

CH3 CH3

CH3

+ H2O + H2

AuSiO2

Scheme 2



2O3and ZrO








3)4) (Scheme 1)




Table3Oxidatio

nof

glucoseb

yvario

uscatalysts

Nam

eofcatalysts

Preparationmetho

dRe

actio

ncond

ition

Mainprod

uct

Selectivity

()Re

ferences

SubstrateOxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)

pHSolvent

Goldnano

particleso

ncellu

lose

Deposition

-redu

ction

O2

mdash60

95Water

Gluconica

cid

mdash[41]

AuA

l 2O3

Deposition

-precipitatio

nO

27

6090

Water

Gluconica

cid

97[79]

AuC

Catio

nica

dsorption

O2

760

90Water

Gluconica

cid

97[79]

Au-PdC

Impregnatio

nO

220

5092

5mdash

Gluconica

cid

mdash[103]

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

H2O

240

90mdash

Sodium

D-gluconate

99[102]

AuC

Goldsol

mdash30

5095

mdashGluconica

cid

45[124]

Nanosized

AuSiO

2Stob

erH

2O2

2430

92Water

Gluconica

cid

80[95]

Pb-TeSiO

2Re

peated

impregnatio

nO

215

6090

mdashGluconica

cid

884

[104]

AuPtb

imetallic

nano

particle

Vacuum

drying

O2

260

95mdash

Gluconica

cid

mdash[80]




AuSiO2

Triethylsilane


Catalyst

Decomposition

H2 + O2 H2O2

2H2O2

H2O + 12O2

Hydrogenation H2








2O3








2O2from H

2and




2O2conversion




SiO2







2O2[53]





3NO3or Au

9L8(NO3)3 L = PPh

3) onto


4



C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus


2


O

Catalysts

Propene epoxide









Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2012

InverseF

e 2O

3Au

(111)m

odelcatalysts

mdashCO

oxidation

[98]

2012

Silica-supp

ortedAu

-Cualloy

mdashAlcoh

oloxidation

[99]

2012

Goldnano

particlessup

ported

onMgO

Deposition

-precipitatio

nAlcoh

oloxidation

[100]

2012

Silica-supp

ortedAu

-CuO119909

Oxidativ

edeallo

ying

Ethano

loxidatio

n[101]

2011

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

oxidation

[102]

2011

Au-PdC

Impregnatio

nGlyoxalandglucoseo

xidatio

n[103]

2011

Pd-Tes

uppo

rted

catalysts

Repeated

impregnatio

nGlucose

oxidation

[104]

2011

Goldnano

particlessup

ported

onfunctio

nalized

mesop

orou

ssilica

One-pot

Synthesis

Cyclo

hexane

oxidation

[105]

2011

Silicas

uppo

rted


Immob

ilizatio

nAlkylbenzeneo

xidatio

n[70]

2011

Goldnano

wire

smdash

Oxidatio

nof

benzyliccompo

unds

[106]

2011

Cu32[PM

o 12O

40]SiO

2Incipientw

etness

impregnatio

nBe

nzylicalcoho

l[107]

2010

Goldnano

particlesd

epositedon

cellu

lose

Deposition

-reductio

ngrinding

metho

dGlucose

oxidation

[41]

2010

Metallopo

rphyrin

boun

dto

silica

Immob

ilizatio

nEthylbenzene

oxidation

[68]

2010

Hydroph

obized

palladium

Vapo

rdeposition

Glucose

oxidation

[108]

2010

Supp

ortedgold

catalysts

Colloidalgold

depo

sition

COoxidation

[109]

2010

AuH

MScatalysts

Impregnatio

nanddirect

synthesis

Benzylalcoho

loxidatio

n[63]

2010

Mob

ilizedgold

nano

particles

Goldsol

Second

aryalcoho

lsoxidation

[67]

2010

Mesop

orou

sCo 3O

4andAu

Co 3O

4catalysts

Nanocastin

gEthylene

oxidation

[110]

2010

Metal-organicfram

eworksupp

ortedgold

nano

particles

Colloidaldepo

sition

Alcoh

oloxidation

[111]

2010

PtA

l 2O3

Impregnatio

nHeavy

hydrocarbo

nsoxidation

[112]

2009

AuTiO

2Deposition

-precipitatio

nAlcoh

oloxidation

[113]

2009

Co(Ac

O) 2M

n(Ac

O) 2

Dire

ctcond

ensatio

np-xylene

oxidation

[114]


Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2009

Nickelsub

stitutedcopp

erchromite

spinels

Cop

recipitatio

nAlkylsubstituted

benzeneo

xidatio

n[9]

2007

Goldcatalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[115]

2007

MCM

-48molecular

sieve

mod

ified

with

SnCl

2Po

st-synthesis

mod

ificatio

nAlcoh

oloxidation

[65]

2007

CuO-im

pregnatedmesop

orou

ssilica

Impregnatio

nBe

nzeneo

xidatio

n[116]

2006

Supp

ortedgold

catalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[117]

2006

Au-C

uOA

l 2O3PtA

l 2O3catalysts

Deposition

-precipitatio

nim

pregnatio

nProp

enea

ndprop

aneo

xidatio

n[118]

2006

Manganese

containing

mesop

orou

sMCM

-41and

Al-M

CM-41

molecular

sieves

Impregnatio

np-iso

prop

yltolueneo

xidatio

n[119]

2005

Goldcatalysts

mdashAlcoh

oloxidation

[120]

2005

AuC

Immob

ilizatio

nGlucose

oxidation

Alcoh

oloxidation

[64]

2005

Goldim

mob

ilizedmesop

orou

ssilica

Immob

ilizatio

nCy

clohexane

oxidation

[121]

2005

Nitrou

soxide

over

MFI

zeolites

Hydrothermal

Benzeneo

xidatio

n[122]

2005

CoA

PO-5

molecular

sieves

Hydrothermal

Cyclo

hexane

oxidation

[123]

2004

Carbon

-sup

ported

gold

Goldsol

Glucose

oxidation

[124]

2004

Mn-containing

MCM

-41

Impregnatio

nEthylbenzene

oxidation

[72]

2003

CoO119909C

eO2

Cop

recipitaion

Carbon

mon

oxideo

xidatio

n[125]

2002

Goldcatalysts

Immob

ilizatio

nGlucose

oxidation

[126]

2002

Mn(Salen)MCM

-41

mdashOlefin

sepo

xidatio

n[127]

2002

NanostructuredCu

O119909C

eO2

Gas-con

densation

Carbon

mon

oxideo

xidatio

n[128]

2002

Nano-Au

Catalysts

mdashCa

rbon

mon

oxideo

xidatio

n[55]

2001

AuTiO

2Au

TiO

2SiO

2Deposition

-precipitatio

nProp

enee

poxidatio

n[129]

2000


Deposition

-precipitatio

nProp

yleneo

xidatio

n[130]

1999

Golddispersedon

TS1and

other

titanium-con

tainingsupp

orts

Disp

ersio

nProp

enee

poxidatio

n[131]

1998


Deposition

-precipitatio

nProp

ylenee

poxidatio

n[61]

1996

Heterop

olycatalysts

containing

Ru(III)

andRh

(III)p

articles

mdashAlkaneo

xidatio

n[132]

1996

Goldsupp

ortedon

ZnOandTiO

2Cop

recipitatio

namp

Deposition

-precipitatio

nCa

rbon

mon

oxideo

xidatio

n[133]

1996

Au-TiO

2Incipientw

etness

impregnatio

nCa

rbon

mon

oxideo

xidatio

n[134]

1995

Bism

uthprom

oted

palladium

catalysts

Ionexchange

Glucose

oxidation

[42]


HO HO

OOH

OHOH

OH OH

OHOH

OH

OH O


Catalysts


Si

ClCl Cl

H


Si CH3

CH3

CH3

Si CH3

CH3

CH3

H3C

Scheme 1

H OH


THF RTSi Si

CH3

CH3 CH3

CH3

+ H2O + H2

AuSiO2

Scheme 2



2O3and ZrO








3)4) (Scheme 1)




Table3Oxidatio

nof

glucoseb

yvario

uscatalysts

Nam

eofcatalysts

Preparationmetho

dRe

actio

ncond

ition

Mainprod

uct

Selectivity

()Re

ferences

SubstrateOxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)

pHSolvent

Goldnano

particleso

ncellu

lose

Deposition

-redu

ction

O2

mdash60

95Water

Gluconica

cid

mdash[41]

AuA

l 2O3

Deposition

-precipitatio

nO

27

6090

Water

Gluconica

cid

97[79]

AuC

Catio

nica

dsorption

O2

760

90Water

Gluconica

cid

97[79]

Au-PdC

Impregnatio

nO

220

5092

5mdash

Gluconica

cid

mdash[103]

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

H2O

240

90mdash

Sodium

D-gluconate

99[102]

AuC

Goldsol

mdash30

5095

mdashGluconica

cid

45[124]

Nanosized

AuSiO

2Stob

erH

2O2

2430

92Water

Gluconica

cid

80[95]

Pb-TeSiO

2Re

peated

impregnatio

nO

215

6090

mdashGluconica

cid

884

[104]

AuPtb

imetallic

nano

particle

Vacuum

drying

O2

260

95mdash

Gluconica

cid

mdash[80]




AuSiO2

Triethylsilane


Catalyst

Decomposition

H2 + O2 H2O2

2H2O2

H2O + 12O2

Hydrogenation H2








2O3








2O2from H

2and




2O2conversion




SiO2







2O2[53]





3NO3or Au

9L8(NO3)3 L = PPh

3) onto


4



C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus


2


O

Catalysts

Propene epoxide









Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




Table2Con

tinued

Year

Catalyst

Metho

dof

preparation

Major

applications

References

2009

Nickelsub

stitutedcopp

erchromite

spinels

Cop

recipitatio

nAlkylsubstituted

benzeneo

xidatio

n[9]

2007

Goldcatalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[115]

2007

MCM

-48molecular

sieve

mod

ified

with

SnCl

2Po

st-synthesis

mod

ificatio

nAlcoh

oloxidation

[65]

2007

CuO-im

pregnatedmesop

orou

ssilica

Impregnatio

nBe

nzeneo

xidatio

n[116]

2006

Supp

ortedgold

catalysts

Deposition

-precipitatio

nAlcoh

oloxidation

[117]

2006

Au-C

uOA

l 2O3PtA

l 2O3catalysts

Deposition

-precipitatio

nim

pregnatio

nProp

enea

ndprop

aneo

xidatio

n[118]

2006

Manganese

containing

mesop

orou

sMCM

-41and

Al-M

CM-41

molecular

sieves

Impregnatio

np-iso

prop

yltolueneo

xidatio

n[119]

2005

Goldcatalysts

mdashAlcoh

oloxidation

[120]

2005

AuC

Immob

ilizatio

nGlucose

oxidation

Alcoh

oloxidation

[64]

2005

Goldim

mob

ilizedmesop

orou

ssilica

Immob

ilizatio

nCy

clohexane

oxidation

[121]

2005

Nitrou

soxide

over

MFI

zeolites

Hydrothermal

Benzeneo

xidatio

n[122]

2005

CoA

PO-5

molecular

sieves

Hydrothermal

Cyclo

hexane

oxidation

[123]

2004

Carbon

-sup

ported

gold

Goldsol

Glucose

oxidation

[124]

2004

Mn-containing

MCM

-41

Impregnatio

nEthylbenzene

oxidation

[72]

2003

CoO119909C

eO2

Cop

recipitaion

Carbon

mon

oxideo

xidatio

n[125]

2002

Goldcatalysts

Immob

ilizatio

nGlucose

oxidation

[126]

2002

Mn(Salen)MCM

-41

mdashOlefin

sepo

xidatio

n[127]

2002

NanostructuredCu

O119909C

eO2

Gas-con

densation

Carbon

mon

oxideo

xidatio

n[128]

2002

Nano-Au

Catalysts

mdashCa

rbon

mon

oxideo

xidatio

n[55]

2001

AuTiO

2Au

TiO

2SiO

2Deposition

-precipitatio

nProp

enee

poxidatio

n[129]

2000


Deposition

-precipitatio

nProp

yleneo

xidatio

n[130]

1999

Golddispersedon

TS1and

other

titanium-con

tainingsupp

orts

Disp

ersio

nProp

enee

poxidatio

n[131]

1998


Deposition

-precipitatio

nProp

ylenee

poxidatio

n[61]

1996

Heterop

olycatalysts

containing

Ru(III)

andRh

(III)p

articles

mdashAlkaneo

xidatio

n[132]

1996

Goldsupp

ortedon

ZnOandTiO

2Cop

recipitatio

namp

Deposition

-precipitatio

nCa

rbon

mon

oxideo

xidatio

n[133]

1996

Au-TiO

2Incipientw

etness

impregnatio

nCa

rbon

mon

oxideo

xidatio

n[134]

1995

Bism

uthprom

oted

palladium

catalysts

Ionexchange

Glucose

oxidation

[42]


HO HO

OOH

OHOH

OH OH

OHOH

OH

OH O


Catalysts


Si

ClCl Cl

H


Si CH3

CH3

CH3

Si CH3

CH3

CH3

H3C

Scheme 1

H OH


THF RTSi Si

CH3

CH3 CH3

CH3

+ H2O + H2

AuSiO2

Scheme 2



2O3and ZrO








3)4) (Scheme 1)




Table3Oxidatio

nof

glucoseb

yvario

uscatalysts

Nam

eofcatalysts

Preparationmetho

dRe

actio

ncond

ition

Mainprod

uct

Selectivity

()Re

ferences

SubstrateOxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)

pHSolvent

Goldnano

particleso

ncellu

lose

Deposition

-redu

ction

O2

mdash60

95Water

Gluconica

cid

mdash[41]

AuA

l 2O3

Deposition

-precipitatio

nO

27

6090

Water

Gluconica

cid

97[79]

AuC

Catio

nica

dsorption

O2

760

90Water

Gluconica

cid

97[79]

Au-PdC

Impregnatio

nO

220

5092

5mdash

Gluconica

cid

mdash[103]

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

H2O

240

90mdash

Sodium

D-gluconate

99[102]

AuC

Goldsol

mdash30

5095

mdashGluconica

cid

45[124]

Nanosized

AuSiO

2Stob

erH

2O2

2430

92Water

Gluconica

cid

80[95]

Pb-TeSiO

2Re

peated

impregnatio

nO

215

6090

mdashGluconica

cid

884

[104]

AuPtb

imetallic

nano

particle

Vacuum

drying

O2

260

95mdash

Gluconica

cid

mdash[80]




AuSiO2

Triethylsilane


Catalyst

Decomposition

H2 + O2 H2O2

2H2O2

H2O + 12O2

Hydrogenation H2








2O3








2O2from H

2and




2O2conversion




SiO2







2O2[53]





3NO3or Au

9L8(NO3)3 L = PPh

3) onto


4



C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus


2


O

Catalysts

Propene epoxide









Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




HO HO

OOH

OHOH

OH OH

OHOH

OH

OH O


Catalysts


Si

ClCl Cl

H


Si CH3

CH3

CH3

Si CH3

CH3

CH3

H3C

Scheme 1

H OH


THF RTSi Si

CH3

CH3 CH3

CH3

+ H2O + H2

AuSiO2

Scheme 2



2O3and ZrO








3)4) (Scheme 1)




Table3Oxidatio

nof

glucoseb

yvario

uscatalysts

Nam

eofcatalysts

Preparationmetho

dRe

actio

ncond

ition

Mainprod

uct

Selectivity

()Re

ferences

SubstrateOxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)

pHSolvent

Goldnano

particleso

ncellu

lose

Deposition

-redu

ction

O2

mdash60

95Water

Gluconica

cid

mdash[41]

AuA

l 2O3

Deposition

-precipitatio

nO

27

6090

Water

Gluconica

cid

97[79]

AuC

Catio

nica

dsorption

O2

760

90Water

Gluconica

cid

97[79]

Au-PdC

Impregnatio

nO

220

5092

5mdash

Gluconica

cid

mdash[103]

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

H2O

240

90mdash

Sodium

D-gluconate

99[102]

AuC

Goldsol

mdash30

5095

mdashGluconica

cid

45[124]

Nanosized

AuSiO

2Stob

erH

2O2

2430

92Water

Gluconica

cid

80[95]

Pb-TeSiO

2Re

peated

impregnatio

nO

215

6090

mdashGluconica

cid

884

[104]

AuPtb

imetallic

nano

particle

Vacuum

drying

O2

260

95mdash

Gluconica

cid

mdash[80]




AuSiO2

Triethylsilane


Catalyst

Decomposition

H2 + O2 H2O2

2H2O2

H2O + 12O2

Hydrogenation H2








2O3








2O2from H

2and




2O2conversion




SiO2







2O2[53]





3NO3or Au

9L8(NO3)3 L = PPh

3) onto


4



C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus


2


O

Catalysts

Propene epoxide









Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




Table3Oxidatio

nof

glucoseb

yvario

uscatalysts

Nam

eofcatalysts

Preparationmetho

dRe

actio

ncond

ition

Mainprod

uct

Selectivity

()Re

ferences

SubstrateOxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)

pHSolvent

Goldnano

particleso

ncellu

lose

Deposition

-redu

ction

O2

mdash60

95Water

Gluconica

cid

mdash[41]

AuA

l 2O3

Deposition

-precipitatio

nO

27

6090

Water

Gluconica

cid

97[79]

AuC

Catio

nica

dsorption

O2

760

90Water

Gluconica

cid

97[79]

Au-PdC

Impregnatio

nO

220

5092

5mdash

Gluconica

cid

mdash[103]

AuA

l 2O3

Incipientw

etness

impregnatio

nGlucose

H2O

240

90mdash

Sodium

D-gluconate

99[102]

AuC

Goldsol

mdash30

5095

mdashGluconica

cid

45[124]

Nanosized

AuSiO

2Stob

erH

2O2

2430

92Water

Gluconica

cid

80[95]

Pb-TeSiO

2Re

peated

impregnatio

nO

215

6090

mdashGluconica

cid

884

[104]

AuPtb

imetallic

nano

particle

Vacuum

drying

O2

260

95mdash

Gluconica

cid

mdash[80]




AuSiO2

Triethylsilane


Catalyst

Decomposition

H2 + O2 H2O2

2H2O2

H2O + 12O2

Hydrogenation H2








2O3








2O2from H

2and




2O2conversion




SiO2







2O2[53]





3NO3or Au

9L8(NO3)3 L = PPh

3) onto


4



C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus


2


O

Catalysts

Propene epoxide









Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials






AuSiO2

Triethylsilane


Catalyst

Decomposition

H2 + O2 H2O2

2H2O2

H2O + 12O2

Hydrogenation H2








2O3








2O2from H

2and




2O2conversion




SiO2







2O2[53]





3NO3or Au

9L8(NO3)3 L = PPh

3) onto


4



C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus


2


O

Catalysts

Propene epoxide









Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




C O

OH

C

O

O

O

H

O2

Mx+Mx+

AuIIIAuIIIAu0

O2minus


2


O

Catalysts

Propene epoxide









Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




Si Si

Si

MeOMeOMeO

+

OH

OH

OH

OHOH

OH

OH

OH

OH

OH

OH

O

O

O

O

O

OFe

Fe

O

O

O

SiO

H

N

H

Nanohybrid APTMS

Toluene


SiO2A

l 2O3

SiO2A

l 2O3

SiO2Al2O3

SiO2A

l 2O3

SiO2A

l 2O3

NH2NH2 + MeOH


SiO2Al2O3-APTMS

24h reflux

NH2 +










2




Me

O

H

O

OH

OEthylbenzene

Acetophenone

Benzaldehyde

Benzoic acid






Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




Table5Ca

talysts

fora

lkylbenzeneo

xidatio

n

Nam

eofcatalysts

Substrate

Oxidant

Reactio

ntim

e(h)

Reactio

ntemperature

(∘ C)solvent

Preparationmetho

dMainprod

uct

Selectivity

()

References

Fenano

catalysts

onthes

urface

SiO

2Al 2O

3TB

HP

2450mdash

Immob

ilizatio

nAc

etop

heno

ne89

[18]

AgSB

A-15

TBHP

590mdash

Impregnatio

nAc

etop

heno

ne99

[35]

Nickelsub

stitutedCu

chromite

spinel

TBHP

870CH

3CN

Cop

recipitatio

nAc

etop

heno

ne69

[9]

Silicas

uppo

rted

cobalt

NHPI

O2

24100CH

3COOH

Immob

ilizatio

nAc

etop

heno

ne91

[70]

AuSBA

-15

Ethylbenzene

TBHP

3670CH

3CN

Insituim

pregnatio

nAc

etop

heno

ne93

[40]

Mn-containing

MCM

-41U

O2

mdash350

Impregnatio

nAc

etop

heno

ne936

[72]

[Fe(tpa)

(MeC

N) 2](ClO

4)2

O2

2475∘C2-bu

tano

nemdash

Acetop

heno

ne54

[135]

a TPF

PPFeCl

O2

24100mdash

mdashAc

etop

heno

ne828

[18]

FeM

gObNHPI

O2

2025mdash

mdashAc

etop

heno

ne52

[18]

Fe(salen)-

c POM

H2O

25

80CH

3CN

mdashAc

etop

heno

ne100

[18]

a Fe(5101520-te

trakis(pentaflu

orop

henyl))

porphyrin

bN-hydroxyph

thalim

ide

c Kegging

type

polyoxom

etalate(K8

SiW11O39)[17]U=un

washed


+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




+

N

NN

N

Mn

OH

OHOH

O

OO

O

O

O

O

OMe

MeO

MeO

O

OO





(EtO)3Si(CH2)3NH2

Si(CH2)3NH

Si(CH2)3NH2














TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




TEOS

Calcination

PEO PPO


H2O HCl AgNO3


+ +



heat





















+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials










+

OH

NH

CHO

OH

N

O

O

N

CoCo

NSi

Si

O

O

N

O

OO

O

OO


Cobalt (II) acetate



NH2(MeO)3Si

(MeO)3Si

(MeO)3Si

Si(MeO)3

SiO2

SiO2

CoSiO2














108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials









108(548 120583molg) 68 94 6 764 23


386(1960120583molg) 79 93 7 274 8


456(2315 120583molg) 89 94 6 256 7


PEO PPO


TEOSCalcination

HAuCl4H2O HCl


MnMn





2impreg-






6 Concluding Remark



Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




Table11M

ajor

metho

dsof

catalysts

synthesis

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Deposition

-precipitatio

n

(a)D

eposition

-precipitatio

nmetho

diseasie

rfor

thes

ynthesisof

vario

ussupp


inpresence

ofexcess

alkali

(b)Inalkalin

emediathe[Au

(en)

2]3+catio

nsared

epositedon

anionico

xide

(TiO

2Fe

2O3Al 2O

3ZrO

2andCeO

2)surfa

ces

having

high

isoelectricpo

int(PIgt70

0)

(c)F

unctionalizationof

oxides

may

take

partin

ther

eactionas

co-catalystsforthe

enhancem

ento

fthe

catalytic

activ

ity

(d)Itisa

very

good

metho

dforthe

oxidationof

alkanesto

epoxides

(a)Itisa


thed

eposition

ofmetal

onto

theo

xide

surfa

ce

(b)Itcanno

tintegrateAu

NPs

onmetaloxides

oflow

isoele

ctric

point(IEPsim2)

such

asSiO

2(c)Itislim

itedto

maxim

um1w

tAu

-loading

(d)Itrequiresm

ultip

lewashing

steps

toelim

inate

excesschlorid

e

[40136137]

Cocon

densation

(a)Itsim

ultaneou

slyform

smesostructure

toanchor

gold

(b)Iteasily

form

shexagon

alarrayof

mesop

ores

andmetal

crystalliteso

f3ndash18n

min

diam

eter

(c)Itisa

simplem

etho

dto

insertgold

nano

particleso

ntothe

surfa

ceof

oxides

(d)Itp

ermits

theformationof

particlesinmetallic

state

surrou

nded

bychlorid

eion

sTh

eseC

lminusions

arethe

basic

species

forc

atalystsactiv

ationdu

ringaceton

ylaceton

e(Ac

Ac)

transfo


ingaseou

sstateandalso

actasp

romotersfor

electrontransfe

rtoO

2du

ringNOredu

ction

with

prop

eneinpresence

ofoxygen

(a)Th

esurface

area

ofcatalysts

preparedby

this

metho

dislow

[136138]

Anion

adsorptio

n

(a)A

queous

anions


anionicfun

ctional

grou

psof

biom

olecules)a

readsorbed

onthee

lectric

allycharged

metaloxides

urfaces

(b)O

ptim

umgold

loadingtakesp

lace

at80∘C

(c)Itisa

simplem

etho

dwith

noneed

fore

xpensiv

einstrumentatio

nsandexpertperson

nel

(a)G

oldloadingcann

otexceed

15wt

(b)Itrequiresm

ultip

lewashing

steps

[137139140

]

Catio

nadsorptio

n

(a)C

atalystcan

beprepared

atroom

temperature

toavoid

decompo

sitionof

them

etalcomplex

andredu

ctionof

gold

(b)H

igherloading

ofgold

(3wt

)can

beachieved

andcatio

nadsorptio

nwith

metalleadstosm

allerp

articles(sim2n

m)w

henthe

solutio

nsupp

ortcon

tacttim

eism

oderate(1h

)

(a)IngeneraltheA

uloadingdidno

texceed2wt

[139141]


Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




Table11C

ontin

ued

Metho

dBriefd

escriptio

nLimitatio

nsRe

ferences

Incipientw

etnessim

pregnatio

n

(a)Interactio

nof

gold

precursorsandthes

uppo

rtsurfa

cetakes

placeb

etweentheo

xygenatom

sofM

e 2Au

(acetonylacetone)a

ndtheO

Hgrou

psof

theS

iO2surfa

ceathigh

temperature

(sim300∘C)

(b)S

trong


etalcatalystandsupp

ort

oxidesTh

uscatalystisno

teasily

lost

(a)Th

echlorides

onsupp

ortp

romotethe

aggregation

ofAu

NPs

andfre

quently

poiso

nthea

ctives

iteso

fthe

catalyst

(b)L

owpH

(lt1)andhigh

temperature

arep

rerequ

isite

(gt300∘C)

Con

tainsh

ighera

mou

ntof

chlorid

eim

purities

(c)Itcanno

tprodu

ceho

mogeneous

andstableparticles

[136137139]

Disp

ersio

n

(a)itisa

nattractiv

emetho

dto

controlthe

aggregationof

AuNPs

(b)P

articlesiz

eisp

reserved

durin

gtheimmob

ilizatio

nste

p(c)P

articlessizec

aneasilybe

controlled

(d)Itish

ighlyselectivea

ndeffi

cient

(a)Itrequirese

xtensiv

ewashing

steps

toremovee

xcess

chlorid

eimpu

rities

[40136]

Chem

icalvapo

rdeposition

(a)S

uppo

rtsa

reevacuatedin

vacuum

at200∘Cfor4

hto

remove

thea

dsorbedwater

(b)IngeneralOMCV

Dmetho

dinvolved

inas

ystem

where

the

prop

ortio

nbetweenthes

ubstr

atea

reaa

ndgasp

hase

volumeg

ets

largersothatthes

urface

reactio

nsho

ldak

eyparameter

(a)Itise

xpensiv

erequ

iresspecialequipm

entandthe

amou

ntof

metalincorporated

bythismetho

dis

somehow

limitedby

pore

volumeo

finertsolid

supp

ort

[142143]

Etching


dsfory

olk-shelln

anop

articles

(b)Itise

fficientcheapera

ndsim

plem

etho

d(a)C

atalystsworkon

lyatlowtemperature

[40144]





Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials







Acknowledgment


References








2(ClO4)2]rdquo


























2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials






2rdquo Catalysis



























2and O

2using Au-Pd









2 120572-Fe

2O3 and CO































2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials






























2O3and






2supported on









pp 162ndash170 2013


















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




















2O3Au(1 1 1)








2O2on an AuAl










32[PMO

12O40]SiO










2O3





















119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials










119909CeO






119909CeO




2and























2O3 SiO2 and TiO


2rdquo














CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials










CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials



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Review Article Heterogeneous Metal Catalysts for Oxidation ...downloads.hindawi.com/journals/jnm/2014/192038.pdf · Review Article Heterogeneous Metal Catalysts for Oxidation Reactions