(1. 沈陽理工大學(xué) 環(huán)境與化學(xué)工程學(xué)院，沈陽 110165；
2. 康平縣環(huán)境保護局，康平 110500)
摘 要: 以水稻秸稈為模板和硅源，采用溶膠-凝膠法制備xRS-Si-BiVO4光催化材料。采用X射線衍射(XRD)、X射線光電子能譜(XPS)、掃描電子顯微鏡(SEM)、比表面積(BET)、傅里葉紅外光譜(FT-IR)、紫外-可見漫反射光譜(UV-vis)等手段對樣品進行表征分析。在可見光照射下，通過光催化降解甲基橙溶液評價xRS-Si-BiVO4的光催化活性。結(jié)果表明：以水稻秸稈為模板制備的樣品具有水稻秸稈相同的微觀形貌，均為單斜型，晶體粒徑比未有模板時的粒徑減小，比表面積增大；水稻秸稈中含有的Si4+離子摻雜進入BiVO4晶體，取代部分V5+離子，以O(shè)—Si—O—V—O鍵存在，晶體內(nèi)V4+離子和氧空位增加，帶隙減小。在可見光下光照50 min后，6RS-Si-BiVO4樣品對甲基橙的脫色率達(dá)93%，較未以秸稈為模板制備的純BiVO4樣品有明顯提高。
關(guān)鍵字: 水稻秸稈；模板；溶膠-凝膠法；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，F(xiàn)T-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
