纳米Au/TiO_2光催化剂的XPS和SPS研究  

XPS and SPS Studies on Nanometer Au/TiO_2 Photocatalyst

作　　者：井立强[1,2] 李晓倩[3] 李姝丹[1] 王百齐[3] 辛柏福[1] 付宏刚[1] 王德军[4] 蔡伟民[3] 

机构地区：[1]黑龙江大学化学化工与材料学院物理化学实验室 [2]哈尔滨工业大学环境科学与工程系,黑龙江哈尔滨150001 [3]哈尔滨工业大学环境科学与工程系 [4]吉林大学化学学院

出　　处：《催化学报》2005年第3期189-193,共5页

基　　金：国家自然科学基金 (2 0 1710 16;2 0 3 0 10 0 6;2 0 43 10 3 0 ) ;教育部科学技术重点项目 (0 2 0 5 1) ;黑龙江省自然科学基金 (B0 3 0 5 ;ZJG0 40 4) ;黑龙江省杰出青年基金 (2 0 0 2 ) ;黑龙江省教育厅骨干教师创新能力资助计划 (10 5 4G0 3 5 ) ;中国博士

摘　　要：以溶胶 凝胶法制备的TiO2 纳米粒子为载体 ,通过浸渍法制备了Au/TiO2 样品 ,并利用XPS和SPS等技术对样品进行表征 ,考察了热处理温度和Au含量对TiO2 纳米粒子光催化氧化苯酚活性的影响 .结果表明 ,Au是以金属纳米微晶的形式均匀地分散在TiO2 纳米粒子表面 .用适量Au进行表面修饰不仅拓宽了TiO2 对光的响应范围 ,而且改善了TiO2 光生电子和空穴的分离效率 ,提高了样品对氧物种的吸附 ,并促进了光生电子向吸附氧的传输 .在光催化氧化苯酚反应中 ,5 0 0℃处理的Au/TiO2 纳米粒子具有较高的光催化活性 ,这与XPS和SPS表征结果是一致的 .从电子能级匹配的角度揭示了Au对TiO2样品表面光电性质和光催化性能的影响机制 .Au/TiO2 samples were prepared by impregnation of TiO2 nanoparticles prepared by sol-gel process with HAuCl4 solution. The samples were characterized by X-ray photoelectron spectroscopy (XPS) and surface photovoltage spectroscopy (SPS) techniques. The effects of calcination temperature and Au content on the photocatalytic activity of TiO2 nanoparticles for phenol degradation were investigated. The results showed that Au was uniformly dispersed on the surface of TiO2 nanoparticles as metal nanocrystallite. The surface modification with appropriate content of Au not only made TiO2 samples expand the response range of light, but also enhanced the separation efficiency of photoinduced electrons and holes, increased the adsorption of oxygen species and promoted the transfer of photoinduced electrons to the adsorbed oxygen species. During the photocatalytic oxidation of phenol, Au/TiO2 calcined at 500 degrees C displayed higher activity, which was in agreement with the XPS and SPS results. The mechanism of Au modification effect on the surface photoelectric properties and photocatalytic performance of TiO2 samples was discussed from the electron energy level point of view.

关 键 词：金 二氧化钛 纳米粒子 表面修饰 光催化 苯酚 

分 类 号：O643.38[理学—物理化学]