二氧化钛的尺寸与光催化活性的关系孙奉玉

:1997-07-03.　:,1971,,..*(29473131)“”.**.*孙奉玉吴　鸣**李文钊李新勇顾婉贞王复东(中国科学院大连化学物理研究所,大连116023)　　-10nm80nm.,XRD,DRS,FS,TiO2,TiO2.16nm,.TiO2.　,,,,,　O643/X5TiO2.TiO2[1].,.,.,.,TiO2[2,3],,TiO2[4,5].Kormann[6]3nmTiO2,Serpone[7]2nmTiO2.-TiO2,,XRD,DRS,FS,TiO2,.1　1.1　　50mlTi(OBu)4(C.P.)200mlC2H5OH(A.R.),15～20min,(1).0.8mlHNO3(A.R.)10mlH2O()30mlC2H5OH(A.R.),(2).(1)(2),30min,,,.,.(373～1073K)3h,TiO2.1.2　　X(XRD)RigakuD/MAX-rbX(CuKT,0.15418nm).TiO23MPa,HI-TACHI200-10-(DRS)..TiO2,HITACHIMPF-419　3　　　19985Vol.19　No.3ChineseJournalofCatalysisMay　1998(FS).10nm,700V.1　Table1　AmountofTiO2catalystSampleT/KZ/%m/gT204730.6930.224T255230.6500.210T305730.6430.207T406730.6410.207T507730.6380.206T608730.6250.202T709730.6200.200T8010730.6200.200TCalcinationtemperature;ZPercentageofthemassoftheTiO2samplesleftaftercalcination;mAmountofTiO2catalystpracticallyused1.3　　[1].0.01g/L100ml;TiO20.200～0.258g.TiO2(、),TiO2,,,TiO2,1.-TiO210min.20min.2　2　TiO2Table2　RelationbetweencrystallinephaseandcrystallitesizeofTiO2samplesandcalcinationtemperatureSampleT/KCrystallinephaseCrystallitesize(nm)T10273AmorphousT15323AmorphousT25523Anatase10.8T30573Anatase12.9T40673Anatase14.9T50773Anatase18.7T55823Anatase,Rutile28.1T60873Anatase,Rutile31.3T70973Anatase,Rutile56.3T801073Rutile81.72.1　XRD　XRD,523K,TiO2.523KTiO2XRD2.523KTiO2.,TiO2.823K,,.1073K,TiO2.2.2　DRS　1TiO2DRS.,,1　TiO2DRSFig1　DiffusereflectionspectraofTiO2samplescalcinedatdifferenttemperatures,T10T20().,,.,(2).TiO23.,2、3,,,.,773K,,773K,.,T30230　　　19T50,5.8nm,12nm;T50T70,37.6nm,30nm.,,.773K,2.07nm,773K,0.09nm..2　DRSFig2　DerivativeanalysisofDRSspectra3　TiO2Fig3　Relationshipbetweentheband-edgepositionofopticalabsorptionandthecrystallitesizeoftheTiO2samples,,,.Brus[8]ΔE=2c22R21me+1mh-1.786e2XR-0.248E*RyR,1me+1mh,memh,X,E*Ry.,1/R2,,.,,,.,,.,T50,T60T70,..,Brus.TiO2(3.0eV)TiO2(3.2eV),773K,,.T70,,T80,,25nm,..2.3　FS　4TiO2.5TiO2.4、5,,.,[2,9].,.,,.2313:4　TiO2FSFig4　FluorescentspectraofTiO2samplescalcinedatdifferenttemperatures3、5,:,;,.,16nm.,,16nm,.16nm-TiO2,,.5　TiO2Fig5　RelationshipbetweenthefluorescencepeakpositionandthecrystallitesizeoftheTiO2samples6　TiO2Fig6　Relationshipbetweenthecrystallitesizeandthecalcinationtemperatureandthephoto-catalyticactivityforphenoldegradationoftheTiO2samples2.4　TiO2　6TiO2c/c0.,,.30nm.30nm10nm,TiO245%.,TiO2,,(320nm),.,,TiO2,TiO2..、、、.,,,,[10,11].16nmTiO2,.16nmTiO2,,TiO2,.AnpoTiO2232　　　19,TiO210nm20nm,[2].,Anpo.773K,,TiO2,.1　,,.,1998,19:1212　AnpoM,ShimaT,KodamaSetal.JPhysChem,1987,91:43053　.[].:,1996.168;974　GiuseppeP,LangfordC,VichovaJetal.JPhotochemPhotobiolA:Chem,1993,75:675　LeeW,GaoY-M,DwightKetal.MaterResBull,1992,27:6856　KormannC,BahnemannDW,HoffmannMR.JPhysChem,1988,92:51967　SerponeN,LawlessD,KhairutdinovR.JPhysChem,1995,99:166468　BrusL.ApplPhysA,1991,53:4659　WellerH,KochU,GutierrezMetal.JPhysChem,1984,88:64910　HoffmannAJ,MillsG,YeeHetal.JPhysChem,1992,96:554611　HoffmannAJ,YeeH,MillsGetal.JPhysChem,1992,96:5540RELATIONSHIPBETWEENCRYSTALLITESIZEANDPHOTOCATALYTICACTIVITYOFTITANIUMDIOXIDESunFengyu,WuMing,LiWenzhao,LiXinyong,GuWanzhen,WangFudong(DalianInstituteofChemicalPhysics,TheChineseAcademyofSciences,Dalian116023)Abstract　SomeTiO2nanoparticlesampleswithsizerangefrom10.8nmto81.7nmwerepreparedbysol-gelmethodwithTi(OBu)4astheprecursor.Theinflu-enceofthepreparationconditionsonthesizeandthecrystallinephaseoftheTiO2crystallitewasstudiedbymeansofX-raydiffraction(XRD)technique,andtheopticalpropertiesoftheTiO2sampleswerecharacterizedbydiffusere-flectancespectroscopy(DRS)andfluorescencespectroscopy(FS).QuantumsizeeffectwasobservedfortheTiO2sampleswithcrystallitesizelessthanca.16nmwhichwasdeterminedbyDRSandFS.TheseTiO2sampleswerealsoper-formedasaphotocatalystindegradationofphenol.Inthesizerange10nm～30nm,thephotocatalyticactivityincreasesdrasticallywiththedecreasingofthecrystallitesize,indicatingthatquantumsizeeffectplaysaveryimportantroleinimprovingthephotocatalyticactivityoftheTiO2sampleswithsmallcrystallitesize.Keywords　Titaniumdioxide,Crystallitesize,Quantumsizeeffect,Phenol,Photocatalysis,Degradation(EdWWQ)2333: