微波法制备 /TiO2催化剂及其光催化氧化性能

摘要

采用微波法、混合加热法和常规加热法制备 /TiO2催化剂 ,运用 XRD、 BET、 DRS及 LRS光谱测定等技术对催化剂的结构进行了表征 ,并以光催化降解 C2H4为模型反应考察了不同制备方法对催化剂的光催化氧化反应性能的影响 .研究结果表明 ,微波法制备的 /TiO2催化剂的光催化氧化性能得到明显改善 ,对乙烯转化率为 80％ ,而混合加热法和常规加热法制备的样品乙烯转化率分别为 58％和 41％ .微波辐射制备的催化剂锐钛矿相含量高、比表面积大 ,光吸收阈值增大；并且拉曼散射光谱向低波数方向移动 ,有助于增加光致电子的跃迁几率 ,提高多相光催化过程的本征量子效率 .%/TiO2 catalysts were prepared by microwave,composite and conventional methods and characterized by X-ray diffraction (XRD),N2 sorption analysis applying BET method,UV-Vis diffuse reflection spectroscopy(DRS) and laser Raman spectrum.The effect of different preparation methods on photocatalytic oxidation of C2H4 in air stream was studied.The results showed that the photocatalytic activity was obviously increased by the microwave method.The conversion of ethylene was 80％ contrast to those of composite and conventional methods being only 58％ and 41％ ,respectively.The catalyst by microwave method exhibited higher content of anatase,higher specific surface area,larger band gap.The Raman scattering shifted to low wave number direction helped to increase the transition probability of photon generated electrons and improved photoefficiency.