Synthesis And Photocatalytic Properties Of Modified BiOI And Bi₂WO₆

With the development of world economy, the environment pollution and energy issues havebecome more and more serious. photocatalytic approaches have attracted an extremelyattention. In the past few years, numerous active photocatalysts have been extensivelyinvestigated, and some of them have been successfully applied in industrial processes.However, due to large band gap and the low separation rate of the photoexcited electron-holepairs greatly restrict their practical applications. Bismuth-containing semiconductorphotocatalysts (Bi2WO6and BiOX et al.) have been intensively investigated due to theirunique crystalline structure and narrow band gap-width. But there are some disadvantages fortheir application such as the requirement of long reaction times and relatively hightemperatures. Hence, it is promising to exploit novel active photocatalysts with high visiblephotocatalytic performances and high stability.In this paper, the effect of Fe3O4and MnO2on BiOI photocatalytic performance, the effectof pH on Bi2WO6photodegradation and morphology were studied. Research contents are asfollows:1. Novel magnetic Fe3O4/BiOI nanocomposites with visible light response weresuccessfully fabricated through a facile and economical method at low temperature andcharacterized by XRD, FTIR, SEM, TEM, HRTEM, SAED. The photocatalytic activity ofFe3O4/BiOI nanocomposites was evaluated by degrading RhB in water. Photocatalyticmechanism and photocatalytic activity enhancement mechanism were investigated.2. The MnO2/BiOI nanocomposites were prepared in the synthetic process of BiOI with thepresence of MnO2and characterized by XRD, SEM. The photocatalytic activity ofMnO2/BiOI nanocomposites was evaluated by degrading RhB in water. The effect of MnO2on BiOI photodegradation was investigated.3. Bi2WO6was synthesized using Bi(NO3)35H2O and Na2WO42H2O as raw material. Inthe process of hydrothermal synthesis, we adjust pH to influence the morphology of Bi2WO6.The mechanism of the effect of pH on Bi2WO6morphology was investigated. Samples werecharacterized by XRD and SEM. The photocatalytic activity was evaluated by degrading RhBin water, the effect of pH on Bi2WO6photodegradation was investigated.