沸石负载介孔TiO_2的制备及其可见光催化性能研究

以人工沸石为载体,采用溶胶-凝胶法,制备出了沸石负载介孔改性TiO2光催化剂。以亚甲基蓝为目标污染物,研究了不同掺杂金属及介孔薄膜制备方法对纳米TiO2可见光催化性能的影响。用扫描电镜(SEM)、紫外-可见吸收光谱(UV-vis)等手段研究了掺杂改性前后TiO2的变化。研究发现,N-Fe掺杂可使催化剂的光吸收谱带红移。当掺杂Fe的比为0.2%,焙烧温度为500℃时制备的TiO2效果最好,在可见光照射2 h后,亚甲基蓝的去除率可达90%。研究表明经十六烷基三甲基溴化铵(CTAB)作为模板剂修饰后的TiO2催化效果有明显提高,通过将经过萃取去除模板剂的共掺TiO2和直接高温焙烧的TiO2对比后发现,前者比后者降解亚甲基蓝的效果要好,原因在于,高温直接焙烧去除模板剂很容易使模板剂形成的骨架塌陷,减小了比表面积,从而影响了其光催化性能。

Preparation and Photocatalytic Property of Nano-TiO2 Loaded on Artificial Zeolite

Photocatalytic properties of nano-TiO2 doped with different substances such as N-Fe,N-Cu,N-Cd on artificial zeolite were studied by using sol-gel process under visible and ultraviolet light.Properties of these materials were characterized by FE-SEM and UV-visible absorption spectroscopy.Results showed that TiO2 doped with N-Fe was the best,and after 2h in the visible light,the degradation rate of methylene blue can reach 90%.Cetyl trimethyl ammonium bromide(CTAB) was used as template to make better catalyst morphology.Two template removal methods were analyzed,and it showed that removal of template by extraction was better than by calcined directly,that may be the high temperature damages the skeleton formed by template,and reduces the surface area,thus affects the photocatalytic properties.