Selective preparation of Bi2O3 visible light-driven photocatalyst by dispersant and calcination

couldbeseennomatterwhatdispersantwasused,thesampleshowedalmostthesamelightabsorptionperformancewiththeothertwo.WhenPEG1000wasused,Bi2O3hadthelargestabsorp-tioninultravioletregion,whileitsabsorptionforvisiblelightwasalittleweakerthanthatofBi2O3synthesizedbyPEG4000andPEG6000.Besides,Bi2O3preparedbyPEG6000showedstronger

(Ahm)2versusphotoenergy(hm)wereabout2.91eV,2.906eVand2.89eVforPEG1000,4000and6000,asshowninFig.3(b).

Tocomparephotocatalyticactivitiesofallthethreesamples,malachitegreensolutionwasusedasthemodelpollutant.Itscon-centrationchangewithirradiationtimeisshowninFig.4.Ingen-eral,Bi2O3preparedbyPEG1000demonstratedthehighestphotocatalyticactivityformalachitegreenalthoughthedifference