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利用沉积-沉淀法将AgBr负载到BiOBr载体上,制备了新型的AgBr/BiOBr复合光催化剂.采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、高分辨透射电子显微镜(HRTEM)和紫外-可见漫反射光谱仪(DRS)对AgBr/BiOBr进行了表征.结果表明,AgBr/BiOBr由面心-立方相的AgBr和四方晶系的BiOBr颗粒构成,其中所负载的AgBr颗粒的平均晶粒尺寸小于28.5 nm.随着AgBr含量的增加,AgBr/BiOBr在可见光区的吸收带边发生红移.光催化实验表明,AgBr/BiOBr在可见光下(>420 nm)可以有效降解甲基橙溶液,当AgBr与BiOBr的摩尔百分比为50%时,AgBr/BiOBr具有最大催化活性,甲基橙的降解速率常数kapp为0.00619 min 1.机理研究表明,.O2在降解甲基橙过程中为主要活性物种,AgBr/BiOBr的催化活性增强主要归结为AgBr与BiOBr之间形成的异质结作用.
A novel AgBr / BiOBr photocatalyst was prepared by depositing AgBr onto a BiOBr substrate by deposition-precipitation method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) The results show that AgBr / BiOBr is composed of AgBr in the face-centered cubic phase and BiOBr particles in the tetragonal system, in which the average grain size of the supported AgBr particles Less than 28.5 nm.With the increase of AgBr content, AgBr / BiOBr red shift occurs in the absorption band in the visible region.The photocatalytic experiments show that AgBr / BiOBr can effectively degrade methyl orange solution under visible light (> 420 nm) AgBr and BiOBr molar ratio of 50%, AgBr / BiOBr has the maximum catalytic activity, methyl orange degradation rate constant kapp 0.00619 min 1. Mechanism studies show that .O2 in the degradation of methyl orange as the main active species, The enhancement of the catalytic activity of AgBr / BiOBr is mainly attributed to the heterojunction formed between AgBr and BiOBr.