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.
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)
