S1 

 

Supporting Information

 

 

Terpyridine‐metalcomplexesoffirstrowtransitionmetalsand

electrochemicalreductionofCO2toCO

NoémieElgrishi,MatthewB.Chambers,VincentArteroandMarcFontecave*

LaboratoiredeChimiedesProcessusBiologiques,UMR8229CNRS,UniversitéPierreetMarieCurie–Paris6,CollègedeFrance,11PlaceMarcelinBerthelot,75005,Paris,France.

LaboratoiredeChimieetBiologiedesMétaux,UniversitéGrenobleAlpes,CNRSUMR5249,CEA,17avenuedesmartyrs,38054GrenobleCedex9,France.

marc.fontecave@cea.fr

Electronic Supplementary Material (ESI) for Physical Chemistry Chemical Physics.This journal is © The Royal Society of Chemistry 2014

S2 

Index Page

FigureS1 FurthercharacterisationofthecyclicvoltammetrybehaviorofCo‐tpy S3

FigureS2 CVsofCo‐tpyunderN2 to–2.75 V S4

FigureS3  FurthercharacterisationofthecyclicvoltammetrybehaviorofNi‐tpy  S5

FigureS4  CVsofNi‐tpyunderN2atslowscanrates S6

FigureS5  CVsofCu‐tpyunderargon andCO2 S7

FigureS6  CVsofFe‐tpyandMn‐tpyunderargonandCO2 S8

FigureS7  ScanaccumulationduringtheCVsofZn‐tpyunderN2 S9

FigureS8  H2andCOproductionovertimebyCo‐tpy at–2.03 V vs. Fc+/Fc S10

FigureS9  BulkelectrolysisofCo‐tpyintheabsenceofH2O S11

FigureS10  BulkelectrolysisofCo‐tpyatvariousappliedpotentials S12

FigureS11  BulkelectrolysisofCo‐tpyinDEFandNMP S13

FigureS12  BulkelectrolysisofNi‐tpyatvariousappliedpotentials S14

FigureS13  BulkelectrolysisofZn‐tpyandreactionwithiodomethane S15

FigureS14  Bulkelectrolysisof4mMtpysolutionsat–2.03Vand–2.23V S16

FigureS15  PhotochemistryofZn‐tpy S17

FigureS16  VariationofthecatalyticpeakcurrentwithCo‐tpyconcentration S18

FigureS17  Steady‐stateorderof0.5inCo‐tpybulkelectrolyses S19

FigureS18 Tafelslopedata S20

FigureS19 VariationoftheCo:tpyratio S21

FigureS20 Schematicrepresentationofthebulkelectrolysiscell S22

FigureS21 SampleFoot‐of‐the‐WaveCalculation S23

 

Figure(black),Top rig(orange1000 (electrodAg/AgCwith0.1Bottom(ν1/2) fatmosp

S1.Toplef,20(red),5ght : cyclice),20(purp(black) mVde, the couCl,3MKCl r1MofTBAPm: ipc (greenfor both ofphere.

ft:cyclicvo50(blue),1c voltammple),50(ligV/s. The wunter electrreferenceePassupporn circles) af the electr

oltammogra100(teal),2ograms ofghtblue),1working elerodewas aelectrode.Trtingelectroand ipa (blurochemical

S3

amsofa2m250(pink),a 2 mM00(pink),2ectrode usa platinumThesolvenolyte.ue squares)l features

mMsolutio,500(greeCO2‐satura250(teal),ed was 1wire, andt systemu

) curves vs(I: left; II:

onofCo‐tpn)and100ated solutio500(darkbmm diamthe referenusedwasD

s. the squarright) of

yunderar00(darkbluon of Co‐tblue),750meter glassnce electroMF/H2O(9

re root ofCo‐tpy un

gonat10ue)mV/s.tpy at 10(red)andy carbonodewas a95:5,v:v),

scan ratender inert

 

Figure–2.33Vthethirelectrodplatinumsolventelectrol

S2.CyclicvVpotentialrdscan issdeusedwamwire,andt system ulyte.

voltammogrange(orashowninthas1mmddtherefereused was

gramsofaange)andthe lattercaiameter glaenceelectrDMF/H2O

S4

Co‐tpysoluthesamesase,asmorassy carborodewasaA(95:5, v:v

utionundeolutionscarescans lednelectrodeAg/AgCl,3v), with 0

rN2atmosanned to–2dtodegrade, the counMKClrefer0.1M of TB

sphereinth2.73V (gredation.ThenterelectrorenceelectBAP as su

he0.06toeen).Onlyeworkingodewasarode.Theupporting

 

Figure(black),Bottomthe(ν1/

usedwwire,ansystem

S3. Top: c,20(red),5

m:ipc(green/2)forbothwas1mmdndtherefeusedwasD

cyclic volta50(blue),1ncircles)anoftheelecdiameter glerenceelectDMF/H2O(

ammograms100(teal),2ndipa(bluectrochemicalassy carbotrodewas95:5,v:v),w

S5

s of a 2m250(pink),esquares)calfeatureson electrodaAg/AgCl,with0.1Mo

mMN2‐satur,500(greecurvesvs.t(II:left;IIIde, the coun3MKClreofTBAPas

rated solutn)and100thesquarer:right).Thnter electroeferenceelesupporting

tion ofNi‐t00(darkblurootofscaneworkingodewas aectrode.Thgelectrolyt

tpy at 10ue)mV/s.nrateforelectrodeplatinumhesolventte.

 

Figurerates (1glassyelectrodDMF/H

S4.Cyclic10mV/s, bcarbon elede was aH2O(95:5,v

voltammogblack; 20mectrode, theAg/AgCl, 3

v:v),with0.

gramsofamV/s, red).e counter e3M KCl re1MofTBAP

S6

2mMN2‐s.Theworkelectrode weference elPassuppor

saturatedsking electrowas a platlectrode. Trtingelectr

solutionofode used winum wireThe solventrolyte.

Ni‐tpyatswas 1 mm, and thet system u

slowscandiameterreferenceused was

 

Figure(lightbscan 38counterreferenassupp

S5.Cyclicblue:scan18). The worelectrodenceelectrodportingelec

voltammog1;darkblueorking electwasaplatde.Thesolvctrolyte. 

gramsofae:scan38)trode usedtinumwire,ventsystem

S7

2mMsoluandunderd was 1 mm,andtheremusedwas

utionofCu‐raCO2atmm diametereferenceeleDMF/H2O

‐tpyat100mosphere(r glassy caectrodewa(95:5,v:v)

0mV/sundred:scan1arbon electasaAg/AgC,with0.1M

derargon1;orange:trode, theCl,3MKClMofTBAP

 

Figuretpy(rig1mmdreferenwasDM

S6.Cyclicght)at100diameterglanceelectrodMF/H2O(95

voltammogmV/s(blueassycarbondewasaA5:5,v:v),wi

gramsundee)andCO2nelectrodeAg/AgCl,3Mth0.1Mof

S8

erargonof(red)atmoe,thecountMKCl referTBAPassu

f2mMsoluospheres.Thterelectrodrenceelectrupportinge

utionsofFeheworkingdewasaplarode.Theslectrolyte.

e‐tpy(left)gelectrodeatinumwiresolventsys

)andMn‐usedwase,andthetemused

S9 

Figure S7. Cyclic voltammograms of a 2 mM N2‐saturated solution of Zn‐tpy and itsevolution as the number of scans is increased. The working electrode used was 1 mmdiameter glassy carbon electrode, the counter electrode was a platinum wire, and thereferenceelectrodewasaAg/AgCl,3MKCl referenceelectrode.ThesolventsystemusedwasDMF/H2O (95:5, v:v),with 0.1MofTBAP as supporting electrolyte. The first scan isrepresented in blue and the last scan in red. Arrows indicate the evolution of theelectrochemicalfeatures.

 

FigureduringatmospDMF/Hofmerc

S8.Totalmthe electro

phere. TheH2O(95:5,vcuryasthe

molesofH2olysis of aworking c

v:v),with0.workingel

(redcircles2mM solucompartme1MTBAPaectrode.Th

S10

s)andCO(ution of Coent of theassupportihecellused

(bluesquaro‐tpy at –2bulk electrngelectrolydisdescribe

res)measur2.03 V vs. Frolysis conyteanda1edinFigure

redinthehFc+/Fc undnsisted of 11.5cmdiameS20.

headspaceder a CO210 mL ofmeterpool

 

Figurepotentiwith0.1S20,usevery 0methodmeasurproducttheline

S9.Top:calelectroly1MofTBAesa1.5cm0.2 s and td over 4 sred inthehtsmeasureearfit,corre

urrent(leftysisofa2mAPassuppomdiameterthe currens. Bottom:headspaceedvs.thetoespondingt

ft,red)andmMCo‐tpyortingelectrpoolofme

nt intensitytotal moleduringtheotalchargetothefarad

S11

charge(riCO2‐saturarolyte.Theercuryasthy data wases of CO (electrolysiepasseddudicefficienc

ght,blue)matedsolutiobulkelectrheworkings smoothedpurple squis(left)anduringtheelcy,is8%fo

measureddonin10mLrolysiscell,gelectroded using anuares) anddchargecolectrolysisorCOand2

duringacoLofanhydr,described.Datawasadjacent‐a

d H2 (greenorrespondi(right).The%forH2.

ontrolled‐rousDMF,inFigurerecordedaveragingn circles)ingtotheeslopeof

 

FigurepotentipotentiBulkelea1.5cmFigureusing aproductelectrolintheta

S10. Curral electrolals(blue:–ectrolyseswmdiameterS20.Datawan adjacentsmeasurelyses.Thesable.

rent (Toplyses of 2–1.93V,redwereperforpoolofmwas recordnt‐averaginged(CO:blueslopesofth

left) and mM Co‐td:–2.03V,gormedin10mercuryastded every0g methodesquares,Hhelinearfits

S12

charge (Ttpy CO2‐sagreen:–2.00mLofDMtheworkin0.2 s and tover 4 s.H2:redcircs,correspo

Top right)aturated s8V,purple

MF/H2O(95ngelectrodethe currentBottom:

cle)vs.thendingtoth

measuredolutions ae:–2.13Va:5,v:v),wite.Thecellut intensityCharge cortotalcharghefaradicef

–1.93V–2.03V–2.08V–2.13V–2.23V

during coat differentndorange:th0.1MTBusedisdesdatawas srrespondingepasseddfficiencies,

CO20% 112% 59% 77% 13% 1

ontrolled‐t applied–2.23V).BAP,usingscribedinsmoothedng to theduringthearegiven

H21%5%7%1%2%

 

FigurepotentidiethylfmM Coperform0.1M TworkinandtheBottomtriangleslopeof

S11. Curral electroformamideo‐tpy) andmedin10mTBAP as sugelectrodeecurrentinm: Charge cesandNMPfthelinear

rent (Toplyses ofe (DEF) (grDMF (redmLofamiupporting ee.ThecelluntensitydatcorrespondP:bluediamfits,corres

left) andCo‐tpy COreen,1mMd, 2 mM CoxtureofDEelectrolyte,usedisdestawassmoding to themonds)vs.spondingto

S13

charge (TO2‐saturateMCo‐tpy), 1o‐tpy) as pEF,NMPorusing a 1cribedinFoothedusine CO produthetotalchothefaradi

Top right)ed solutio1‐methyl‐2primary sorDMFresp.5 cm diamFigureS20.nganadjaceuced (in Dhargepassecefficiency

measuredns at –2‐pyrrolidinolvent. Bulkpectivelywmeter poolDatawasrent‐averagiDMF: red sedduringty,is12%in

during co.03 V usnone (NMP)k electroly

with5%ofHl of mercurrecordedevingmethodquares, DEtheelectrolnthethreec

ontrolled‐ing N,N‐) (blue,1yses wereH2O,withry as thevery0.2sdover4s.EF: greenlyses.Thecases.

 

FigurepotentipotentielectrolcmdiamS20.Daadjacenmeasurelectrolintheta

S12. Curral electrolals (blue:lysesweremeterpoolatawasrecnt‐averaginred (CO: blyses.Thesable.

rent (Toplyses of 2–1.72 V,performedofmercurycordedeverg methodblue squareslopesofth

left) and2 mM Ni‐tred: –1.76din10mLoyasthewory0.2sandover 4 s.es, H2: redhelinearfits

–1.72V–1.76V–1.89V–2.14V

S14

charge (Ttpy CO2‐sa6 V, greenofDMF/H2Oorkingelectdthecurre. Bottom:d circle) vs,correspo

COV 18%V 17%V 17%V 16%

Top right)aturated sn: –1.89 VO(95:5,v:vtrode.ThecentintensitCharge covs. the totndingtoth

H20%0%0%0%

measuredolutions aand oran

v),with0.1cellusedistydatawasorrespondintal chargehefaradicef

during coat differentnge: –2.141MTBAP,udescribedssmoothedng to thepassed dufficiencies,

ontrolled‐t appliedV). Bulksinga1.5inFigure

dusinganproductsuring thearegiven

S15 

Figure S13. Current (Top left) and charge (Top right) measured during controlled‐potentialelectrolysesof5mMZn‐tpyCO2‐saturatedsolutionsat–2.15V.Bulkelectrolyseswere performed in 10 mL of DMF/D2O (95:5, v:v), with 0.1M LiClO4, using a 1.5 cmdiameter pool ofmercury as theworking electrode. The cell used is described in FigureS20.Datawasrecordedevery0.2sandthecurrentintensitydatawassmoothedusinganadjacent‐averagingmethodover4s.Bottom:Attheendofthebulkelectrolysis,200µLofiodomethane(3.2mmol)wasaddedtrough the septum of the electrochemical cell and the solution was stirred at roomtemperature for 1h30min. The aliphatic (right) and aromatic (left) regions of 1H NMRspectra before the addition of CH3I (black) and after reaction with CH3I (blue) arepresented here. The spectra have been referenced to the aldehyde proton of DMF (7.9ppm).TheRedstarsmarktheappearanceofnewpeaksafterreactionwithCH3I.

 

Figureelectrol(green)10mLothewor0.2 s anover4s

S14. Curlyses of 4m)andCO2(rofDMF/H2Orkingelectnd the curs.

rrent (left)mM terpyrred)andatO(95:5,v:vrode.Thecrrent intens

and charridine solut–2.23Vunv),with0.1cellusedissity data w

S16

rge (right)tions. ElectnderCO2(bMTBAP,ussdescribedwas smooth

) measuredtrolyses calue).Bulkesinga1.5cd inFigurehed using a

d duringrried out aelectrolysesmdiameteS20.Dataan adjacen

controlled‐at –2.03 Vswereperfrpoolofmwasrecordnt‐averaging

‐potentialunder Arformedinmercuryasdedeverygmethod

 

Steady pressurecollimatwere prcontroll

Sample triethanodeuteratsolutionZn-tpy,solutionThe resuwith COcap withwas plapipettedincludin0.4 mL

Figure presenceto triethdark; RuRu(bpy)associatobservepeaks on

State Photoe Hg/Xe arcting lens, a repared in a ed cuvette h

preparatioolamine. Tted solvent n of Ru(bpy, two sampln mixed witulting 0.8 mO2 via vigorh a septum. ced in the d

d from the qng only Ru(of Zn-tpy s

S15. 1H Ne of 2.0 mMhanolamine.u(bpy)3Cl2()3Cl2(H2O)6

ted with TEd post-photnly observe

olysis Detac lamp (Orie

filter holde1 cm path

holder (Qua

on involvedThis solvent

accessibili)3Cl2(H2O)6

les were math 0.4 mL omL solutionrous bubbliOne of the

dark for the quartz cuvett(bpy)3Cl2(Hstock solutio

NMR spectrM Ru(bpy)3C. (a-c) FromH2O)6 photo

6 and Zn-tpyEOA marketolysis of Zd post-phot

ails. Photochel Instrumener equippedlength quar

antum North

d the use t system wity. The sol

6 and a 2.0 made in tandemof the Ru(bpn (2.0 mM Rng of CO2

samples prsame lengthte into an N

H2O)6 were pon being rep

ra for the pCl2(H2O)6 inm top to boolyzed; bothy photolyzeed by *. (b

Zn-tpy preseolysis of Zn

S17

hemical Reants). The be

d with a 415rtz cuvette (

hwest) main

of a 5:1was chosen

lvent mixtumM stock sm, each of py)3Cl2(H2ORu(bpy)3Cl2

through therepared was h of time. U

NMR tube foprepared anplaced by 0.

photolysis on a CO2-satuottom, the sh Ru(bpy)3Cd. (a) The fb) Aromatiented in redn-tpy presen

actions wereeam was pa5 nm band (Starna) whtained at 20

1 volumetrdue to pra

ure was usesolution of Zwhich inclu

O)6 stock so

2(H2O)6 ande solution fothen photol

Upon complor analysis vnd treated in4 mL of the

of experimeurated 5:1 vspectra reprCl2(H2O)6 afull spectra aic resonancd. (c) Aliphnted in red.

e performedassed throug

pass filter, hich was pla0°C with a c

ric ratio oactical consed to prepaZn-tpy. Foruded 0.4 mLolution withid 1.0 mM Zfor 15 minutlyzed for 6 letion the revia 1H NMRn an analoge solvent mi

ents of 1.0volumetric rresent Ru(band Zn-tpy are shown wces are shohatic resona

d using a 30gh an infrare

and an irisaced in a tecirculated w

of acetonitrsiderations are a 4.0 mr photolysis L of the Zn-in the quart

Zn-tpy) wastes throughhours while

eaction mixtR. Photolysigous manneixture.

0 mM Zn-tratio of acetpy)3Cl2(H2Oin the dark

with the intewn with p

ances are sh

0 W, high ed filter, a s. Samples mperature ater bath.

rile-d3 to regarding

mM stock including

-tpy stock tz cuvette. s saturated a cuvette e the other tures were is samples r with the

tpy in the tonitrile-d3 O)6 in the ; and both ense peaks eaks only

hown with

S18 

 FigureS16. Variationof Icatwith the concentration ofCo‐tpy in CO2‐saturated solutionsduringcyclicvoltammetryexperimentsat50mV/s.Theworkingelectrodeusedwas1mmdiameter glassy carbon electrode, the counter electrode was a platinum wire, and thereferenceelectrodewasaAg/AgCl,3MKCl referenceelectrode.Thesolventsystemusedwas DMF/H2O (95:5, v:v), with 0.1M of TBAP as supporting electrolyte. The correlationcoefficientofthelinearfit(red)is0.98.

 

Figurecontrolconcentreachedcurrentlight blcircles:DMF/Hworkinabove tsurfacewere cpotentibulkele

S17. Plotled‐potentitrations ofdtheplateatateachpolue triangle–1.99 V, b

H2O (95:5, vg electrodethe pool ofofthemercorrected fal.Theslopectrolysesc

of the logial electrof Co‐tpy whauregionaotentialwaes: –2.07 Vblack squarv:v), with 0e. In an effmercuryrcuryelectfor the valpeofthelinconditions,

Ap–––––––

(current(Aolyses ofhere the pandthenvaasrecordedV, dark blures: –1.97 V0.1M TBAPffort to obwas stirredtrode.Theclues observnearfits,coisgivenin

Appliedpotential or–1.97V–1.99V–2.02V–2.04V–2.07V–2.17V–2.27V

S19

)) vs. the lCo‐tpy

otentialwaariedinastd(yellowdiue trianglesV). Bulk elP, using a 1btain activad as vigorocellusedisved in a sorrespondithetable.

ApparentrderinCobal

0.460.470.440.470.500.680.74

log(concenCO2‐saturaas first heltepmanneriamonds:–s: –2.04 V,lectrolyses1.5 cm diaation contrously as posdescribedsolution wingtothea

tcorrelatcoefficie

0.930.930.950.930.940.970.99

tration(moated solutd at –2.03revery302.27V,pingreen triawere perfmeter poorolled condossible witdinFigurewithout Co‐apparentor

tionent

ol/L)) obtaitions atV until thminandthnktrianglesangles: –2.0formed inl ofmercuditions, thethout disruS20.Curre‐tpy, at earderinCob

ined in 6differente currentheplateaus:–2.17V,02 V, red10mL ofury as thee solutionupting theentvaluesach givenbaltunder

 

Figuredescribandgrefit(not

S18. PlotbedinFigureentrianglerepresente

of appliedreS17(blaes:0.5mMed)ofthe–1

potential vacksquaresofCo‐tpy).1.9Vto–2.

S20

vs. log(currs:2mM,re.AtallCo‐t1Vregion

rent(A)) exedcircles:1tpyconcenis~135mV

xtracted fro1mM,bluetrations,thV/dec).

om the expetriangles:heslopeoft

periments0.75mMthelinear

 

Figureelectrol2mM t2mMCwasrecaveragiv:v),wiThe celmeasurelectrol

S19. Top:lysesofCOtpy and 2mCoCl2(greencordedeveingmethodith0.1MTBll used is dred (CO: blyses.

current (lO2‐saturatedmMCoCl2n)andamry0.2sandover4s.BBAP,usingdescribed iblack squar

eft) and chdsolutions(yellow), 4mixtureof2ndthecurreBulkelectroa1.5cmdn Figure Sres, H2: re

S21

harge (righsat–2.03V4mM tpy a2mMCoCl2entintensitolyseswerediameterpo20. Bottomed circle) v

ht)measureVof:2mMand 2mM2,2mMtpytydatawaseperformeoolofmercm: charge cvs. the tot

ed during tpy (blue)CoCl2 (puryand2mMssmoothededin10mLcuryasthecorrespondtal charge

controlled‐),2mMCorple), 1mMMbpy(browdusinganLofDMF/Heworkingeding to thepassed du

‐potentialoCl2 (red),M tpy andwn).Dataadjacent‐H2O(95:5,electrode.productsuring the

 

FigureThewoofmercworkinelectrodfloatingcan beanalysedirectc

S20.Schemorkingcompcuryusedag and refede by a pogoverthepsampled

es.Anadditcyclicvoltam

maticreprepartment(asworkingrence electorous glasspoolofmerthrough rutionalglassmmetryexp

esentationo(10mL,oragelectrodetrodes ares frit. The srcury.Theubber septsycarboneperimentso

S22

oftheelectrange),onthand theAseparatedsolution iselectrocheta using gelectrodecofthebulk

rochemicalheleft,contAg/AgCl, 3Md from theconstantlymicalcelligas tight syanbefittedsolution.

lcellusedftainsthe1MKCl refercoiled platy stirred wisgastightyringes fordthrough

forbulkele.5cmdiamrenceelectrtinum wirewith a smalt,andthehr gaseousoneofthe

ctrolyses.meterpoolrode.Thee counterll stir barheadspaceproductsseptafor

S23 

SampleFootoftheWaveCalculationConstantsR=GasConstant=8.31446(CV)/(molK)T=Temperature=297KF=FaradaysConstant=96485.34C/molVariablesiop=peakcurrentintheabsenceofsubstrate(CO2)i=currentmeasuredundercatalyticconditionsν=scanrateofCVinV/sCoA=Concentrationofsubstrate(CO2)inthebulksolutioninmol/LE=appliedpotentialinVEoPQ=(Epa+Epc)/2measuredforreactioncouple(Co(tpy)2+/Co(tpy)2)intheabsenceofCO2inVEoAB=potentialforCO2reductiontoCOunderconditionsusedinV=overpotentialinVk2=secondorderrateconstantkap=pseudo‐firstorderrateconstantunderexcessofCO2TOF0=TurnoverFrequencyat0appliedoverpotentialTOF=TurnoverFrequencyataspecifiedoverpotentialValuesofVariablessetbyExperimentorEstimatedfromLiteratureν=0.250V/sCoA=0.23mol/LEstimatedfromReference1EoAB=–1.41Vvs.Fc+/FcEstimated fromReference1whichreports thepotentialas–0.690Vvs.NHEwiththeFc+/Fcpotentialtakentobe0.720Vvs.NHE4ValuesofVariablesMeasuredbyExperimentsinabsenceofCO2iop=peakcurrentintheabsenceofsubstrate(CO2)EoPQ=–2.03Vvs.Fc+/FcValuesRecordedduringCatalyticCVsi,ECalculationsofRateConstantandTurnoverFrequency2,3The following relationship from Reference 2 (bottom of first column on page 11238) isutilized:

.

Plottingthefollowingrelationship

transformsatypicalCV(acurrentvs.Potentialplot)intoaformwhereintheslopeoftheofthelinearregionofthelowpotentialvaluesprovidesaccesstotherateconstantk:

 

or

TheCVS19.

FigureSblacktradataat locathodicThe reddetermThesloconstan

Thesecrate co(assum

2.24 2

.

foundinF

21.Footofthacerepresentsowpotentialsscan,whileth

d trace repinedbyelipeoftheabntcanbeca

.

, .

, .

condordernstant canedtobe0.2

4

2

FigureS1ca

heWaveAnalsthetransfors.Thevariabherightploti

presents thiminatinghbovetrendalculatedas

.

4

rateconstan be obtain23M)andi45.5 – –

anbetrans

lysisplotsforrmedelectrocble fequalsF/includesonly

he linear trhigherpotedlineisfousfollows:

.

.

45.5

antisthusn bymultipisfoundto0.23

S24

sformedint

rCo(tpy)2(PFchemicaldata/(RT).The leythelinearize

rend line fentialsuntindtoequa

. /

calculatedplying by 4be10.5s–1

10.5 –

totheblack

F6)2catalyticra.Theredtraeftplot includedregionatlo

for the lowil a trendwl3.2791.Th

. /

.

tobe45.545.5 M–1 s–.

ktracesho

reductionintacerepresentdestheentirowoverpoten

w overpotewithanR2=hereforeth

M–1s–1.Th1 by the co

ownbelow

thepresencetsthetangentecatalyticrentials.

ential regio=0.99washesecondo

epseudo‐fioncentratio

inFigure

ofCO2.Thetlinetotheegionof the

on. It wasachieved.orderrate

firstorderon of CO2

S25 

Thispseudofirstorderrateconstantcanbetransformedintoaturnoverfrequencyviathefollowingrelationshipfoundinreference2,basedoffofequation4withinsaidreference,whichwasslightlyamendedwithinreference3.log log

Inanefforttocomparetheactivitytoothervaluesreportedintheliterature,ofparticularinterest is the activity of the catalyst at zero overpotential. Using the pseudo‐first orderrateconstantderivedabove,theTOF0canbecalculatedassuch:log log

log 10.5 .

.

1.41 2.03 0

1.0212 16.96895 0.62 9.5

Thus,thelog(TOF0)atzerooverpotentialiscalculatedtobe–9.5.ThiscorrespondstoanintrinsicTOFequalto3.2×10–10M–1s–1.Theaboveprocedurewas followedforallof thedifferentscanratesanalyzedwithinthismanuscript.Practically,within thecatalyticwave that isobservedexperimentally, there isanappliedoverpotentialof0.670V.ThiscanbebeincludedinthecalculationofTOFasshownbelow:log log

log 10.5 .

.

1.41 2.03 0.67

1.0212 16.96895 – 0.05 1.9Thus,thelog(TOF)withanappliedoverpotentialof0.670V,representingconditionswithinthecatalyticwavefoundexperimentally,iscalculatedtobe1.9.ThiscorrespondstoaTOFequalto7.4×101s–1.References1)C.Costentin,M.RobertandJ.‐M.Saveant,Chem.Soc.Rev.,2013,42,2423.2)C.Costentin,S.Drouet,M.RobertandJ.‐M.Saveant,J.Am.Chem.Soc.,2012,134,11235.3)C.Costentin,S.Drouet,M.RobertandJ.‐M.Saveant,J.Am.Chem.Soc.,2012,134,19949.4)S.Creager,inHandbookofElectrochemistry,ed.C.G.Zoski,Elsevier,Amsterdam,1stedn,2007,ch.3,pp.101.