CdS量子点敏化1ZnO纳米棒阵列电极的制备和光电化学性能

[Article](WuliHuaxueXuebao)ActaPhys.-Chim.Sin.,2010,26(11)：2927-2934NovemberReceived:May17,2010;Revised:August23,2010;PublishedonWeb:September21,2010.*Correspondingauthor.Email:[e-mail];Tel:[phone].TheprojectwassupportedbytheNationalNaturalScienceFoundationofChina(20433040).(20433040)鬁EditorialofficeofActaPhysico-ChimicaSinicaCdSZnO22221,2,*1,2(1,361005;2,361005)：CdSZnO.(SEM)、X(XRD)(TEM)CdS/ZnO、;-CdS.,0.1mol·L-115ZnO.ZnOCdS,,-(IPCE)380nm76%.CdS,.,,.：ZnO;CdS;CdS/ZnO;;：O646PreparationandPhotoeletrochemicalPerformanceofCdSQuantumDotSensitizedZnONanorodArrayElectrodesZHANGQiao-Bao2FENGZeng-Fang2HANNan-Nan2LINLing-Ling2ZHOUJian-Zhang1,2,*LINZhong-Hua1,2(1StateKeyLaboratoryofPhysicalChemistryoftheSolidSurface,XiamenUniversity,Xiamen361005,FujianProvince,P.R.China;2DepartmentofChemistry,CollegeofChemistryandChemicalEngineering,XiamenUniversity,Xiamen361005,FujianProvince,P.R.China)Abstract：WesensitizedCdSquantumdotsonaZnOnanorodarrayelectrodebythesuccessiveioniclayeradsorptionandreactionmethod.Scanningelectronmicroscopy(SEM),X-raydiffraction(XRD),andtransmissionelectronmicroscopy(TEM)experimentswereperformedtocharacterizethemorphology,crystallinephase,andgrainsizeoftheCdSquantumdotsensitizedZnOnanorodarrayelectrodes.TheeffectofCdSdepositioncyclenumberandtheprecursorconcentrationwerestudiedbyphotocurrent-potentialcharacteristicsandphotocurrentspectra.Theresultsshowedthatthebestphotoelectrochemicalperformancewasobtainedat0.1mol·L-1forbothCd2+andS2-after15cycles.Meanwhile,thecompositefilmsexhibitedaremarkablyenhancedphotoelectricconversionefficiencycomparedwiththeZnOnanorodsarrayfilmsandwithCdSquantumdotelectrodes.Themonochromaticincidentphoton-to-electronconversionefficiency(IPCE)wasashighas76%at380nm.ThismaybeattributedtothebroadlightharvestingcapabilityofCdSandtheefficientseparationofphotogeneratedcarriersonitsinterface.Thereasonforthisenhancementwasfurtherconfirmedbyaphotoluminescentexperiment.TheresultsshowedthatsensitizationwithCdSquantumdotsreducedtherecombinationofelectronandholepairsresultinginanenhancementinthephotocurrent.2927ActaPhys.-Chim.Sin.,2010Vol.26KeyWords：ZnOnanorodarray;CdSquantumdots;CdSquantumdots/ZnOnanorods;Successiveioniclayeradsorptionandreactionmethod;Photoelectrochemicalperformance(ZnO)、、,[1].ZnO(Eg=3.2eV),(TiO2),ZnO(205-300cm2·V-1·s-1),ZnOTiO2[2].ZnOZnO,ZnO(4%-5%)[2-3];,.,ZnO.,:,;,;3,,,,[4-6].II-VI,CdSe、PbS、CdTeCdS,,[5-6].CdS[7],[8-9],ZnO[10].CdSZnO[3,11-15].Ganesh[3]CdSZnO,8.CdS,,[12].Lee[13]CdSZnO,,-(IPCE)16%.CdS,,.,CdSZnO、.ITOZnO,CdSZnO.ZnO,,.,,,[11,14-15].,380nm76%,ZnOCdS7.65.4.CdS,.,.11.1:(,),Zn(NO3)2·6H2O、Na2S·9H2O、Cd(NO3)2、、(,),3CdSO4·8H2O(,),、(,),ITO(25-35Ω·cm-2,).:PAR173,AMETEK;S4800FESEM,Hitachi;TecnaiF30300kV,Philips-FEI;PanalyticalXpertPROX,;Cary5000--,Varian;F-7500,Hitachi;273/,AMETEK;5210,AMETEK;275,ARC.1.22928No.11：CdSZnO1.2.1ITOITO、,10-20min,.1.2.2ZnOZnO,[16].0.25mA·cm-2,90℃,60min.1.2.3CdS(QDs)ZnO(NRs)0.1mol·L-1Cd(NO3)25min,,0.1mol·L-1Na2S5min,,CdS.1.2.4CdSQDsITO0.3mol·L-1Cd(NO3)25min,,0.3mol·L-1Na2S5min,,8,CdSQDs/ITO.1.2.5150WLPX150(200-2500nm)、AMETEKModel273A/、Model194、Model5210(0.1mol·L-1Na2S1mol·L-1KCl)[17].LaserProbeRK-5720,50mW·cm-2,0.1cm2.22.1CdSZnOXRD10.1mol·L-1Cd(NO3)20.1mol·L-1Na2S15CdSZnO(c),ITO/ZnO(b)ITO(a)X(XRD),1b,2θ31.8°、34.4°、36.3°、47.5°、56.5°、62.8°、67.9°,(100)、(002)、(101)、(102)、(110)、(103)、(112)、(004),ZnO,ZnO.,,ZnO.(002),ZnOc,ITO[16].1c2θ=26.6°(PDF2-00-001-0647)CdS(111),,CdS,(111)ScherrerCdS3nm.2θ43.97°51.90°,ZnO,CdS.2.2CdSZnO20.1mol·L-1Cd(NO3)20.1mol·L-1Na2SCdSZnOSEM.2(a),ZnO,150nm,.5,2(b),CdS.,1(c,d),CdSZnO.15,CdS.CdSZnO.315CdS/ZnOTEM.3(a),ZnO,150nm,SEM.3(b),ZnOCdS.,3-6nm(3(c)).,1ITO(a),ZnO(b)CdS/ZnO(c)XRDFig.1XRDpatternsofITOsubstrate(a),ZnOnanorodarrays(b),andCdSquantumdot/ZnOnanorodfilms(c)2929ActaPhys.-Chim.Sin.,2010Vol.260.337nm,CdS(111),XRD.CdS,X(EDS).415CdSZnOEDS,,Cd、S、Zn、O,CdS3.28∶3.14,1∶1.2ZnO(a)CdSCdS/ZnO(b-d)SEMFig.2SEMimagesofZnOnanorods(a)andCdSquantumdot/ZnOnanorodarrayswithdifferentCdSdepositoncycles(b-d)depositioncycle:(b)5,(c)10,(d)153ZnO(a)15CdS/ZnO(b);15CdS/ZnO(c,d)Fig.3TEMimagesofZnOnanorods(a)andCdSquantumdots/ZnOnanorodsforCdSdepositionof15cycles(b)andhigh-resolutionTEMimagesofCdSquantumdots/ZnOnanorodsforCdSdepositionof15cycles(c,d)2930No.11：CdSZnOCdS.2.3CdSZnO50.1mol·L-1Cd(NO3)20.1mol·L-1Na2SCdSZnO.,ZnO,.350nm,(373nm).ZnO[18].CdS480nm,CdS(520nm)40nm,.(3,5,7,10,15).,ZnOCdS,,,.6CdS/ZnOCdS,,CdS,,CdS15,,1.6mA·cm-2.,CdS,CdS;CdSZnO,CdSZnO,-,.7.,ZnOCdS,0.070.48mA·cm-2.(5,7,10,13,15,17,20),CdSZnO,50.45mA·cm-2,151.6mA·cm-2,.64CdS/ZnOX(EDS)Fig.4EnergydispersiveX-rayspectroscopy(EDS)spectrumofCdSquantumdot/ZnOnanorodarrayelectrode5CdS、ZnOCdSCdS/ZnO-Fig.5UV-VisspectraofCdSquantumdots,ZnOnanorods,andCdSquantumdot/ZnOnanorodarrayelectrodesfordifferentCdSdepositioncycles3,5,7,10,15arethedepositioncycles.6CdS/ZnOCdSFig.6ThecurveofsaturatedphotocurrentdensityofCdSquantumdot/ZnOnanorodcompositeelectrodewiththedepositioncycleofCdSquantumdotsE/keV2931ActaPhys.-Chim.Sin.,2010Vol.26.,ZnO-0.55V15-1.23V,CdS.8.,ZnO,CdS