Nanotechnology

RSET, 2011-12 Engineering PhysicsNanotechnology

4/10/20121

Nanotechnology


4/10/20122

1. Introduction• Nanotechnology

– Study of structures with at least one characteristic dimension measured in

nanometer range

• Range: Atomic size (10-9m) to Bulk macroscopic materials (10-7m), i.e. 1-100nm

– Physical properties of nano-materials are different from atoms or bulk materials

– Some nano-materials could harm human health or environment

• Short History

– Michael Faraday (1857)

• Discovery of colloidal gold particles

– Karl Wilhelm Wolfgang Ostwald (1917)

• Book ―Welt der vernachlaessigten Dimensionen ― or the ―World of negligible

dimensions‖

– Study of colloidal state of matter

– Richard Feynman (1950)

• Lecture at American Physical Society: ―There is plenty of room at the bottom‖

– On manipulating miniscule bits of condensed matter


2. Classification

• Nanostructures confined in 3D: 3 dimensional nanostructures– Nanoparticles

– Nanopores

– Quantum dots

• Nanostructures confined in 2D: 2 dimensional nanostructures– Nonowires

– Nanorods

– Nanofilaments

– Nanotubes (Carbon nanotubes, Silicon nanotubes)

• Nanostructures confined in 1D: 1 dimensional nanostructure– Nanodiscs

– Nanoplatelets

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Nanorings

• Zinc Oxide Nanoring (2004)– The first nanoring by Georgia Institute of Technology, USA

– A single-crystal seamless nano-ring

– Made of piezoelectric zinc oxide of diameter of about 3 microns and thickness 15nm

– Made by a new crystal growth process: Spontaneous self-coiling process of nanobelts

• Layers of nanobelts are rolled together as coils, layer-by-layer

• Other examples– Silver nanoring

– Gold nanoring

– Carbon nanoring

• Applications of nanorings– Real-time monitoring of blood pressure

– Measurement of blood flow rate

– Measurement of stress at the a single cell scale

– Micro-and nano-electromechanical systems (MEMs NEMs)

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Nanorods• General Method of Preparation

– Direct chemical synthesis in the presence of a shape control agents, like ligands

• Ligand: Ion or molecule that binds to a central metal atom to form a coordination complex

– Different faces of nanorod grows at different rates, producing rod-like elongated object

• Diamond Nanorods or Nanodiamond or hyper diamond (2003)– Made by compression of graphite or fullerene

– The hardest and least compressible known material

• Isothermal bulk modulus of 491 GPa , in contrast to diamond with 442-446 Gpa.

• 0.3% denser than regular diamond

• Hardness and Young's modulus comparable to that of natural diamond, but with "superior wear

resistance―

• Gold Nanorods– Preparation: Photochemical method employing UV-irradiation to facilitate slow growth of rods

– Uses: In vitro and in vivo biomedical applications

• Minimal inherent cytotoxicity

• Silicon Nanorods– Silicon nanorod solar cell: Developed by the California Institute of Technology in Pasadena

• The nanorods are assembled into a ―carpet‖ and embedded into a transparent polymer

• Flexible solar cells that use only 1% of the material as conventional silicon cells

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Nanodiamond

ZnO Nanorod

Gold Nanorod

Si Nanorod


Nanoparticles

• Definition– Particles sized between 1-100 nm, characterized by size-dependent properties

• Reason for Nano effects– Due to significant percentage of atoms at the surface of a material

– Due to the large surface area per weight of the material, which make them more reactive

• Examples– Iron Oxide nanoparticles: Improves MRI (Magnetic Resonance Imaging) images of cancer

tumors

– Palladium nanoparticles: Detection of Hydrogen

– Iron Nanoparticles: Clean up CCl4 pollution in ground water

– Silicon nanoparticles: Increase battery power and reduce recharge time

– Gold Nanoparticles: Allow heat from infrared lasers to be targeted on cancer tumors

– Silicate nanoparticles: Stops gasses or moisture in plastic films used for packing

– Zinc oxide nanoparticle: Coating on wood, plastic and textiles to protect them from UV rays

– Silver nanoparticles: Kills bacteria making clothing making it odor-resistant

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Gold NanoparticlesMagnetic nanoparticle

http://www.bnl.gov/bnlweb/pubaf/pr/photos/2007/CryoEmProteasomeGold3-300.jpg

http://topnews.in/usa/files/nanoparticles.jpg


Nanoshells

• Nanoshells– Spherical nanoparticle, consisting of a dielectric core covered by a thin metallic shell (usually

gold)

– Nanoshells involve a quasiparticle called plasmon

• Plasmon oscillation: A collective excitation where the electrons simultaneously oscillate

with respect to all the ions

• Plasmon oscillation is tunable

– Thickness of the shell and overall particle radius determines which wavelength of

light it couples with

– Interacts with a broad range of the light spectrum that spans the visible and near

infrared regions depending on the shape

• Synthesis– E.g. Gold nanoshell: Reduction using tetrachloroauric acid

• Applications– Biomedical imaging: E.g. Cancer treatment using gold nanoshells

– Fluorescence enhancement of weak molecular emitters

– Surface enhanced Raman spectroscopy

– Surface enhanced infrared absorption spectroscopy

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Gold Nanoshell


Fullerenes and Nanotubes

• Buckminster Fullerenes (C60)

– History• Kroto and Smalley (1985): Strange results in mass spectra of evaporated carbon samples

• Name: A homage to Richard Buckminster Fuller, whose geodesic domes it resembles

– Definition• Fullerenes are a class of allotropes of carbon which conceptually are graphene sheets of

linked hexagonal/pentagonal /heptagonal rings rolled into tubes or spheres.

– Spherical and ellipsoidal carbon nanomaterials are referred to as fullerenes or bucky balls

– Cylindrical ones are called nanotubes or buckytubes

– Properties• High tensile strength

• High ductility

• High electrical conductivity

• High heat conductivity

• Relative chemical inactivity (as it is cylindrical and "planar" — that is, it has no "exposed"

atoms that can be easily displaced).

– Applications• Electronics: Organic solar cells, Transistors

• Medicine: Antioxidants and biopharmaceuticals; Controlling neurological damage due to

Alzheimer's disease 4/10/20128


Fullerenes and Nanotubes• Carbon Nanotubes (CNTs) or Bucky tubes

– Discovery: Sumio Iijima and co., 1991• Large length (~microns) and small diameter (~nm)

– spect ratio (132,000,000:1) : Near 1D form of Fullerenes

– Types:• Single-walled CNT: Zig-zag, Armchair and Chiral

– Band gap: 0-2 eV: Metallic/semiconducting behavior

• Multi-walled CNT: Multiple rolled layers of concentric tubes: Inter-layer distance ~3.4 A˚

– Zero band gap

– Properties

• Electronic

– Efficient electrical conductors

• Mechanical

– Strongest in terms of tensile strength and stiffest in terms of elastic modulus

Single wall CNT: Y = ~1054 Gpa; Tensile Strength (150 Gpa), ρ (1.3-1.4 g/cm3)

Multiwall CNT: Y = ~1200 Gpa; Tensile Strength (150 Gpa), ρ (2.6 g/cm3)

Steel: Y = 208Gpa; Tensile Strength ( 0.4Gpa), ρ (7.8 g/cm3)

– Reason: Sp2 bonds formed between the individual carbon atoms

• Thermal

– Thermal conductivity along the axis of SWNT: ~3500 W/m.K (Copper: 385 W/m.K)

– Thermal conductivity across the axis of SWNT: ~1.52 W/m.K ~ that of soil

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Nanocomposites

• Nanocomposites– Solid combination of a bulk matrix and nano-dimensional phase(s)

• Matrix: Leads to superior overall properties compared to constituent properties e.g.

optical clarity, strength, stiffness, permeability

– Size limits for different properties:

• <5 nm: Catalytic activity

• <20 nm: To make a hard magnetic material soft

• <50 nm: For refractive index changes

• <100 nm: For achieving super-paramagnetism, mechanical strengthening or restricting

matrix dislocation movement.

– Preparation:

• Incorporation of additive to a ceramic/metallic matrix leading to intra-granular

dispersions

– Generate and fix dislocations during processing: annealing, cooling,

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Nanocomposites

• Types

– Ceramic-matrix nanocomposites• Matrix of ceramic material (Al2O3, MgO, Si3N4, SiC, etc.)

• Al2O3 /W, Mo, Ni, Cu, Co, Fe; ZrO2 /Ni, Mo; MgO/Fe, Co, Ni, etc.

– Homogeneous dispersions of metallic particles within the ceramic matrices

• Improves optical, electrical and magnetic properties as well as tribological, corrosion-resistance and

other protective properties, Fracture strength, toughness, hardness, etc.

– Metal-matrix nanocomposites• E.g.: Carbon nanotube metal matrix composites (TNCMMC)

– Economically viable

– Provides for a homogeneous dispersion of nanotubes in the metallic matrix

– Leads to strong interfacial adhesion between the metallic matrix and the carbon nanotubes

• Properties: Improved wear resistance, friction coefficient, or thermal conductivity

– Polymer-matrix nanocomposites (PNC) • Polymer nanocomposites (PNC)

– Combination of polymer or copolymer matrix and additives of nanosize.

– 1D (Nanotubes, fibers), 2D (Layered minerals like clay) and 3D (spherical particles)

– Polymer: E.g. Polyamide (Nylon): a thermoplastic polymer, glass fiber, carbon fiber, etc.

– E.g. Reinforce a polymer matrix by much stiffer nanoparticles of ceramics like clays, or carbon

nanotubes.

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Nanocomposites

– PNC Properties

• High strength

– Because of the higher surface area of the nano-particles, the interaction with the

other particles within the mixture is more

E.g. silicon nanospheres which show quite different characteristics; their

size is 40 – 100 nm and they are much harder than silicon, their hardness

being between that of sapphire and diamond

• Heat resistance

– Reduction in heat resistance

E.g. Dispersion of metal nanoparticles within the polymer matrix, enhance

the conductivity of the polymers.

– Polymer-carbon nanotube composite– Improved electrical conductivity

– Enhancement of thermal conductivity and thermal stability, fire retardancy

– Enhancement of oxidation stability

– Outstanding mechanical properties : Elastic stiffness, strength, barrier resistance,

scratch/wear resistance

– Excellent optical, magnetic and electrical properties

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Properties of Nanoparticles

• Optical Properties– Fundamental reasons for unique optical properties

• Size of nanoparticle is comparable to the size of EM radiation, or λ

• Elastic light scattering, absorption, reflectance and transmittance, second

harmonic generation, nonlinear optical properties, surface enhanced Raman

scattering, etc. are size-dependent properties for nanomaterials

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―Labors of the Months‖

(Norwich, England, ca.

1480). Ruby color

probably due to gold

nanoparticles

The Lycurgus Cup (glass;

British Museum; 4th century A.

D.)

Lycurgus: A Tarcian King

When illuminated from outside,

it appears green.

Shorter wavelengths are not

absorbed

When illuminated from within,

the Lycurgus cup glows red.

The red color is due to tiny

gold particles embedded in

the glass (about 40 parts per

million). Absorption peak at

around 520 nm


Optical Properties of Nanoparticles

• Different Optical Properties

– Change in colour

• E.g. Gold nanoparticles appear deep red to black in colloidal solution

• E.g. Silicon (Gray) Nanoparticles are red in color

– Absorption properties

• Greater absorption of solar radiation

– Absorption of nanoparticle photovoltaic cells is greater than that of thin film solar

cells

– Since the smaller the particles, the greater the solar absorption

– E.g. Silver nanoparticles: For efficient harvest of light

– E.g. Silver nanoparticles in Metal-enhanced fluorescence (MEF) and in surface-

enhanced Raman scattering (SERS)

– Superior UV blocking properties

• E.g. Zinc oxide nanoparticles

• E.g. ZnO nanoparticles: Due to photostability ZnO is used in the preparation of sunscreen

lotions

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Electrical Properties of Nanoparticles

• Electrical Resistivity– Larger Resistivity

• E.g. Ni-P alloy (363 Ohm-cm) v/s Ni-P nano-crystal (622 Ohm-cm)

– Size-dependent electrical resistivity

• Increase in both resisitivity and in residual resistivity (T->0) with decreasing size

– Due to increased volume fraction of atoms lying in the grain boundaries

– Electrical conductivity is proportional to the grain size

• Temperature coefficient of resistance (TCR) – TCR decrease with a reduction in size

• Due to enhanced scattering from grain boundaries

• Grain boundaries are modelled as potential barriers of certain height and width

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Electrical Properties of Nanoparticles

• Ballistic Conduction in Carbon and Silicon nanowires– Ohm’s law is not valid for nanowires

• Strictly linear relationship between current and voltage is replaced by a nonlinear law

– Explanation

• Electrical conductivity of metal is characterized by the free mean path of electrons

– Diffusive conductance: Scattering of free electrons in the conductor causes resistance

– Ballistic Conductance: Characterized by unimpeded flow of charge or energy carrying

particles over relatively long distances in a material

• If the geometric dimensions reach the mean free path length of electrons, the mechanism of

conduction changes from a ―diffusive‖ to a ―ballistic‖

• Superconduction– Weak-coupling Type I superconductors (Al, Sn)

• Increase in Tc with decrease in size

– Due to softening of surface phonon modes

– Strong-coupling Type-I superconductor (Pb)

• Doesnot change Tc down to particle size of ~6nm

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Magnetic Properties of Nanoparticles

• Reason for special magnetic properties– Magnetic properties of a single isolated particle are strongly influenced by the particle size

– Magnetic moment per atom increases as size of the nanoparticle decreases

• Number of surface atoms increases as cluster size decreases

• Ferromagnetism as universal feature of nanoparticles– Ferromagnetism is exhibited by nanoparticles of intrinsically non-magnetic materials

• CeO2, TiO2, Al2O3, and MgO

• Nitrides such as GaN and chalcogenides such as CdS and CdSe

– Ferromagnetism of the nanoparticles is confined to the surface

– For nanoparticle, coercivity or remanence increases with decrease in size

• Super paramagnetism– Further decrease in particle size leads to zero remanence and coercivity called

Superparamagnetism

• E.g. SPIONS: Super Paramagnetic Iron Oxide Nanoparticles (Biomedical application)

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Magnetic Properties of Nanoparticles• Applications

– Giant Magnetic Resistance

• Albert Fert and Peter Grünberg: Nobel Prize in 2007 for the discovery of GMR

– Change in the electrical resistance depending on whether the magnetization of

adjacent ferromagnetic layers are in a parallel or an anti-parallel alignment.

The overall resistance is relatively low for parallel alignment and high for anti-

parallel alignment

– Commercial application in production of hard disk drives (CD)

– Magnetic Nanocomposites

• Magnetic nanocomposites finds applications in the areas of heath care, catalysis, and

environmental separation

– Magnetic nanoparticles with core/shell structures

• Biomedical applications: Useful due to their tailored dimensions and compositions

affecting magnetic behavior

– Size, shape and biochemical coating could be controlled

• Used in magnetic bio-sensing, Cell separation, Contrast enhancement in MRI, cell

labeling, targeted drug delivery, Hyperthermia (cancer treatment)

– Magnetic tapes

• Reducing the magnetic grain size and narrowing the size distribution are two key issues in

high density magnetic recording.

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Mechanical Properties of Nanomaterials

• Reason for enhanced mechanical properties

– Reduced imperfections

• The small size either renders nanomaterials free of internal structural imperfections such

as dislocations, micro twins, and impurity precipitates

• The few defects or impurities present can not multiply sufficiently to cause mechanical

failure

• Self-purification process : The imperfections within the nano dimensions are highly

energetic and will migrate to the surface to relax themselves under annealing, purifying

the meterial and leaving perfect material structures inside the nanomaterials

• The external surfaces of nanomaterials also have less or free of defects compared to bulk

materials, serving to enhance the mechanical properties

• E.g. Superior mechanical properties of carbon nanotubes

– High density of grain boundaries

• 50% or more atoms are situated in the grain boundaries

• Two types of atomic arrangements

– Crystalline arrangement: All atoms located in the lattice of the crystallite

– Interfacial arrangement: All atoms situated in the grain or interface boundaries

between the crystallte

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Mechanical Properties of Nanomaterials

• Hardness– Super-hard composites made of nitrides, borides and carbides by plasma-induced chemical and

physical vapor deposition

• E.g. Nanocomposites ~50GPa, though individual nitrides has hardness ~21GPa

• Nearly spherical, defect-free silicon nanospheres with diameter 20-50 nm has hardness

~50GPa (4 times greater than the bulk silicon)

• Young’s Modulus– Single wall carbon nanotube: Y~1000 GPa

– Multiwall carbon nanotube: Y ~ 500-6000 Gpa

– Steel: ~200GPa

• Tensile Strength– Measured by checking ―Sword-in-sheath‖ failure

• Failure mode corresponding to the sliding of the layers within the concentric MWNT assembly

– ~11-63 Gpa (Steel ~1-2 Gpa)

– Applications: High frequency electro-mechanical resonators from carbon nanotubes

and nanowires

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Mechanical Properties of Nanoparticles

• Diffusion and sintering

– The high surface area to volume ratio of nanoparticles provides a tremendous driving force for

diffusion, especially at elevated temperatures

– Sintering can take place at lower temperatures, over shorter time scales than for larger

particles.

• Self-Cleaning effect

– E.g. Presence of titanium dioxide nanoparticles imparts self-cleaning effect

• Stronger plastics

– Clay nanoparticles when incorporated into polymer matrices increase reinforcement, leading to

stronger plastics, verifiable by a higher glass transition temperature

• Melting point

– Gold nanoparticles melt at much lower temperatures (~300 °C for 2.5 nm size) than the gold

slabs (1064 °C)

• Larger Glass Transition temperature

– These nanoparticles are hard, and impart their properties to the polymer (plastic).

– Nanoparticles have also been attached to textile fibers in order to create smart and functional

clothing

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Quantum Confinement

• Quantum Confinement effects

– Size-dependent property of nanomaterials

• A particle behaves as if it were free when the confining dimension is large compared to the

wavelength of the particle

– During this state, the band-gap remains at its original energy due to a continuous

energy state

• As the confining dimension decreases and reaches a certain limit, typically in nanoscale,

the energy spectrum turns to discrete

– Diameter of the particle is of the same magnitude as the wavelength of the electron

wave function

– Band-gap becomes size-dependent

– Blue shift in optical illumination as the size of the particles decreases

• The smaller the size of the nanoparticle, the larger the band gap, the greater the

difference in energy between the highest valence band and the lowest conduction band

becomes

• More energy is needed to excite the dot, and concurrently, more energy is released when

the crystal returns to its resting state

• Their electronic and optical properties deviate substantially from those of bulk materials

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Quantum Confinement

4/10/201223

http://en.wikipedia.org/wiki/File:Quantum_confinement_1.png


Quantum Confinement

• Exciton Bohr Radius

– Electrons and electron holes being squeezed into a dimension that approaches a critical

quantum measurement, called the exciton Bohr radius.

• 3D confinement: Quantum dot

• 2D confinement: Quantum wire

• 1D confinement: Quantum well

• Applications

– Fluorescent dye applications

• Higher frequencies of light emitted after excitation of the dot as the crystal size grows

smaller, resulting in a color shift from red to blue in the light emitted

• Because of the high level of control possible over the size of the crystals produced, it is

possible to have very precise control over the conductive properties of the material

– Other Applications

• Nanoparticles act as artificial, man-made atoms with discrete electronic spectra

• Enhanced Lasers

• Discrete components in nanoelectronics, qubits for quantum information processing

• Enhanced ultra-stable fluorescent labels for biosensors to detect, for example, cancers,

malaria or other pathogens, and to do cell biology

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Applications

• Areas of applications– In materials science, nanoparticles allow for the making of products with

new mechanical properties, including surface friction, wear resistance,

and adhesion.

– The smallest components of a computer chip are on a nanoscale.

– In biology and medicine, nanomaterials are used to improve drug design

and targeting. Others are being developed for analytical and

instrumental applications.

– Consumer products such as cosmetics, sunscreens, fibres, textiles,

dyes, and paints already contain nanoparticles.

– In electronic engineering, nanotechnologies are used for instance to

design smaller, faster, and less consuming data storage devices.

– Optical devices such as microscopes have also benefited from Logic

circuits, magneto-electronic devices, magnetic data storage, medicine,

biotechnology

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Applications

• Uses of Nano-powder: – Particle of size ~100nm

• High-density magnetic recording materials

• Absorbing stealth materials

• Magnetic fluid materials

• Radiation shielding material

• Silicon and precision optical polishing materials

• Micro-chip thermal conductivity of the substrate and the wiring material

• Microelectronic packaging materials

• Optoelectronic materials

• Advanced battery electrode materials

• Solar cell materials

• Efficient catalyst

• Efficient accelerant

• Sensitive components

• High toughness ceramic material (not crack the ceramic fell for ceramic engines, etc.)

• Body repair materials

• Anti-cancer agents.

4/10/201226


Applications• Nano-fiber

• Micro-conductors

• Micro fiber (future quantum computer) materials

• New laser or light-emitting diode materials

• Nanofilms

• Gas catalyst (such as automotive exhaust gas) materials

• Filter material

• High-density magnetic recording materials

• Photosensitive material

• Flat panel display materials

• Superconducting materials

• Nanoblocks

• High strength materials

• Intelligent metal materials

• Semiconductor nanostructures

– Nanostructures in the emitting region of injection laser reduces threshold current

requirement and decreases the device temperature

4/10/201227


Applications of Nanotechnology

• Medicine– Biomedical nanotechnology, nano biotechnology, nano medicine

• Size of nanomaterials are comparable to biological molecules

• In vivo and in vitro biomedical applications

– Diagnosis

• Nanotechnology-on-a-chip is one more dimension of lab-on-a-chip

technology

• Magnetic nanoparticles are used to label specific molecules,

structures or microorganisms

• Gold nanoparticles are used to detect of genetic sequence

• Multicolor optical coding for biological assays by embedding

different-sized quantum dots into polymeric microbeads

• Nanopore technology for analysis of nucleic acids converts strings

of nucleotides directly into electronic signatures

4/10/201228



• Medicine– Drug Delivery

• The overall drug consumption and side-effects can be lowered

significantly by depositing the active agent in the morbid region only

and in no higher dose than needed

– Reduces costs and human suffering

– Dendrimers, Nanoporous material, Block co-polymers

– Nano Electromechanical systems (NEMS) for active release of drugs

– Implantable drug delivery systems

• Cancer treatment with iron nanoparticles or gold shells

– Gold nanoparticles with a polyelectrolyte coating can make smaller

tumors more visible through X-ray

• Buckyballs can "interrupt" the allergy/immune response

– Tissue Engineering

• Bones regrown on carbon nanotube scaffolds

4/10/201229



• Environment– waste-water treatment, air purification and energy storage

devices

– Nanoporous membranes are suitable for a mechanical filtration

with extremely small pores smaller than 10 nm (―nanofiltration‖)

and may be composed of nanotubes

– Ultrafiltration, which works down to between 10 and 100 nm

• Renal dialysis

– Magnetic nanoparticles offer an effective and reliable method to

remove heavy metal contaminants from waste water

– Using nanoscale particles increases the efficiency to absorb the

contaminants and is comparatively inexpensive compared to

traditional precipitation and filtration methods

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Applications of Nanotechnology• Energy

– Themes: Storage, conversion, manufacturing improvements by

reducing materials and process rates, energy saving (by better

thermal insulation for example), and enhanced renewable

energy sources

– Reduction of energy consumption

• Nanotechnological approaches like light-emitting diodes (LEDs) or

quantum caged atoms (QCAs) could lead to a strong reduction of

energy consumption for illumination

– Increasing the efficiency of energy production

• Nanotechnology could help increase the efficiency of light

conversion by using nanostructures with a continuum of bandgaps

• Spray-on nanoparticle substance as a solar collector (Uty of

Toronto)

– Recycling of batteries

• Rechargeable batteries or supercapacitors with higher rate of

recharging using nanomaterials4/10/2012

31



• Information and Communication– Memory Storage

• carbon nanotube based crossbar memory called Nano-RAM

(Nantero)

• use of memristor material as a future replacement of Flash memory

(HP)

– Novel semiconductor devices

• Based on spintronics

• Based on GMR - Giant Magneto-Resistance

– Hard discs of gigabyte range

• Based on Tunneling magnetoresistance (TMR)

– Non-volatile main memory for computers, such as the so called

magnetic random access memory or MRAM

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– Novel optoelectronic devices

• photonic crystals and quantum dots

• Photonic crystals

– Photonic crystals are materials with a periodic variation in the refractive

index with a lattice constant that is half the wavelength of the light used

– Displays

• displays with low energy consumption could be accomplished using

carbon nanotubes (CNT)

• CNT as as field emitters with extremely high efficiency for field

emission displays

– Quantum computers

• The Quantum computer has quantum bit memory space termed

"Qubit" for several computations at the same time

4/10/201233



• Heavy Industry– Aerospace

• Nanotech is lowering the mass of supercapacitors

• Reduce the size of equipment and there by decrease fuel-

consumption

– Catalysis

• Extremely large surface to volume ratio

– Platinum nanoparticles as automotive catalytic converter

– Construction

• Nano-cement, nano-steel, Nanoparticles in Glass, Nanoparticles in

coatings, Nanoparticles in fire protection and detection, etc.

• Consumer Goods, etc.– Nanofood, self-cleaning or ―easy-to-clean‖ surfaces on ceramics

or glasses, Nanooptics, Nanotextiles, Nanocosmetics,

Agriculture

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