摘要
用表面改性法制备TiO2/S iO2,以等体积浸渍法制备负载型复合半导体催化剂(MoO3,ZnO)-TiO2/S iO2,通过XRD、BET、TPR、IR、UV-V is DRS和TPD等技术对材料的表面形态结构、吸光特性、化学吸附性能及光催化甲烷和水的反应性能进行了表征和分析。结果表明,MoO3-TiO2/S iO2和ZnO-TiO2/S iO2的表面物种均具有显著的量子尺寸效应,在表面分别形成Mo—O—Ti和Zn—O—Ti复合结构;MoO3和TiO2在载体表面的复合可提高对光能的利用率并可增强对甲烷的化学吸附性能,结果使得MoO3-TiO2/S iO2的光催化反应性能明显优于ZnO-TiO2/S iO2;在固定床环隙反应器中,150℃MoO3-TiO2/S iO2光催化气相甲烷和水合成了目的产物甲醇和氢,甲醇的选择性达到87.3%。
TiO2/SiO2 were prepared by the chemical modification reaction on SiO2, then the supported coupled semiconductors （MoO3, ZnO）-TiO2/SiO2 were prepared by isovolumic impregnating TiO2/SiO2. The surface structure, chemical adsorption capabilities, photon absorption properties and photocatalytic behaviors of MoO3- TiO2/SiO2 and ZnO-TiO2/SiO2 were systematically investigated by the techniques of X-ray differaction （XRD）, BET, temperature programmed reduction （TPR）, UV-Vis DRS, IR and temperature programmed desorpsion （TPD）. The surface species of MoO3-TiO2/SiO2 and ZnO-TiO2/SiO2, comprising Mo-O-Ti and Zn-O-Ti bonds respectively, have the quantum size effects due to the supports interaction. The supported coupled semiconductors MoO3-TiO2/SiO2 exhibits higher photocatalytic activity than ZnO-TiO2/SiO2, because chemisorption property of CH4 and utilization of the photo energy enhanced effectively when MoO3 was incorporated on TiO2/ SiO2. CH3OH and HE are produced by the gas-phase photocatalytic reaction of CH4 and H2O over MoO3-TiO2/ SiO2 catalyst at 150℃ in a fixed-bed annular photoreactor, and the CH3OH selectivity is 87.3%.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2006年第3期332-336,共5页
Journal of Fuel Chemistry and Technology
基金
国家重点基础研究发展规划(973计划
2001CCAO3600)
