(1. 沈阳理工大学 环境与化学工程学院，沈阳 110165；
2. 康平县环境保护局，康平 110500)
摘 要: 以水稻秸秆为模板和硅源，采用溶胶-凝胶法制备xRS-Si-BiVO4光催化材料。采用X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、比表面积(BET)、傅里叶红外光谱(FT-IR)、紫外-可见漫反射光谱(UV-vis)等手段对样品进行表征分析。在可见光照射下，通过光催化降解甲基橙溶液评价xRS-Si-BiVO4的光催化活性。结果表明：以水稻秸秆为模板制备的样品具有水稻秸秆相同的微观形貌，均为单斜型，晶体粒径比未有模板时的粒径减小，比表面积增大；水稻秸秆中含有的Si4+离子掺杂进入BiVO4晶体，取代部分V5+离子，以O—Si—O—V—O键存在，晶体内V4+离子和氧空位增加，带隙减小。在可见光下光照50 min后，6RS-Si-BiVO4样品对甲基橙的脱色率达93%，较未以秸秆为模板制备的纯BiVO4样品有明显提高。
关键字: 水稻秸秆；模板；溶胶-凝胶法；BiVO4；甲基橙
（1. College of Environmental and Chemical Engineering, Shenyang Ligong University, Shenyang 110165, China;
2. Kangping Environmental Protection Bureau, Kangping 110500, China）
Abstract:xRS-Si-BiVO4 photocatalysts were synthesized by sol-gel method using rice stem as template and silicon source. The prepared samples were characterized by XRD, XPS, SEM, BET，FT-IR and UV-vis DRS analyses, and the photocatalytic activities were investigated by photocatalytic degradation of methyl orange (MO) under visible light irradiation. The results show that the samples prepared with rice stem as template have the same morphology of rice stem. The crystal sizes of all xRS-Si-BiVO4 samples are smaller than those of pure BiVO4 prepared without rice stem, but the phase of all samples is still monoclinic phase. Si4+ ions from the rice stem are doped into the BiVO4 lattice and replace some of V5+ ions to form O—Si—O—V—O bond, which leads to more V4+ ions and oxygen vacancies in RS-BiVO4 lattice, and narrower band-gap. The degradation rate of MO under visible light irradiation for 50 min is 93% for 6RS-Si-BiVO4, which is much higher than that of pure BiVO4.
Key words: rice stem; template; sol-gel method; BiVO4; methyl orange
