Visible-light photocatalytic activity and mechanism of novel AgBr/BiOBr prepared by deposition-precipitation  

作　　者：LIN HaiLi CAO Jing LUO BangDe XU BenYan CHEN ShiFu 

机构地区：[1]College of Chemistry and Materials Science, Huaibei Normal University, Huaibei 235000, China

出　　处：《Chinese Science Bulletin》2012年第22期2901-2907,共7页

基　　金：supported by the National Natural Science Foundation of China(20973071,51172086);Natural Science Foundation of Educational Committee of Anhui Province(2012Z356);Youth Foundation of Huaibei Normal University(2011xqxm31)

摘　　要：A new composite photocatalyst AgBr/BiOBr was prepared by loading AgBr on a BiOBr substrate via deposition-precipitation and characterized by X-ray diffraction,scanning electron microscopy,high-resolution transmission electron microscopy and UV-vis diffuse reflectance spectroscopy.The as-prepared AgBr/BiOBr comprised face-centered cubic AgBr and tetragonal BiOBr particles.The average crystalline sizes of AgBr in the AgBr/BiOBr composites were less than 28.5 nm.The absorption edges of AgBr/BiOBr in visible-light region had a red shift with increasing AgBr content.Photocatalytic degradation of methyl orange results show that the AgBr/BiOBr composites could degrade methyl orange efficiently under visible-light irradiation (λ>420 nm).The optimal molar percentage of AgBr was 50 mol% with corresponding maximum k app of 0.00619 min -1.Active ·O 2- played a major role for methyl orange degradation while h + and ·OH had little effect on the photocatalytic process.The enhancement of photocatalytic activity of AgBr/BiOBr is mainly ascribed to the heterojunction effect between AgBr and BiOBr.A new composite photocatalyst AgBr/BiOBr was prepared by loading AgBr on a BiOBr substrate via deposition-precipitation and characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and UV-vis diffuse reflectance spectroscopy. The as-prepared AgBr/BiOBr comprised face-centered cubic AgBr and tetragonal BiOBr particles. The average crystalline sizes of AgBr in the AgBr/BiOBr composites were less than 28.5 nm. The absorption edges of AgBr/ BiOBr in visible-light region had a red shift with increasing AgBr content. Photocatalytic degradation of methyl orange results show that the AgBr/BiOBr composites could degrade methyl orange efficiently under visible-light irradiation （λ〉420 nm）. The optimal molar percentage of AgBr was 50 mol% with corresponding maximum kapp of 0.00619 rain-1. Active · O（-,2） played a major role for methyl orange degradation while h＋ and · OH had little effect on the photocatalytic process. The enhancement of photo- catalytic activity of AgBr/BiOBr is mainly ascribed to the heterojunction effect between AgBr and BiOBr.

关 键 词：光催化活性 可见光区 溴化银 沉积 沉淀 AGBR 扫描电子显微镜 透射电子显微镜 

分 类 号：O644.1[理学—物理化学]