Ce-TiO2/硅藻土的制备、表征及其光催化活性
来源期刊:中国有色金属学报2007年第5期
论文作者:雷波 徐悦华 郭来秋 罗海燕
文章页码:795 - 795
关键词:TiO2;硅藻土;Ce掺杂;TiO2/硅藻土;光催化
Key words:TiO2; kieselguhr; Ce doping; TiO2./kieselguhr; photocatalysis
摘 要:
以硅藻土(KL)为载体,用溶胶-凝胶法将铈掺杂二氧化钛包覆在硅藻土上(Ce-TiO2/KL)。采用XRD、DRS、SEM对其进行表征,以250 W高压汞灯作光源,甲醛作为反应底物表征其光催化活性。结果表明:Ce-TiO2包覆在硅藻土颗粒上,并能在较高的煅烧温度(500 ℃)范围内保持锐钛矿晶体结构;随着铈掺杂含量的提高,J2Ce-TiO2/KL对可见光的吸收明显增强,有利于充分利用太阳光。由此可见,TiO2固定在硅藻土上时,铈掺杂不仅提高了其活性,还导致其激发波长红移,还有利于回收利用。
Abstract: Ce-TiO2/kieselguhr photocatalysts were prepared by sol-gel method under alkalescent conditions, and characterized by X-ray diffractrometry, scanning electron microscopy and DRS. The photocatalytic degradation of formaldehyde was chosen as a model reaction to evaluate the photocatalytic activities of the composite photocatalysts irradiated by 250 W high-pressure mercury lamp. The results show Ce-TiO2 coating on kieselguhr. The crystalline phase of titanium dioxide is still only anatase in wide range of temperature. The light absorption in visible region increases with increasing Ce-doping content in J2Ce-TiO2/kieselguhr, so it is beneficial to use sun’s ray. When Ce-TiO2 is immobilized on kieselguhr, Ce-doping not only enhances its photocatalytic activity, but also extends its respond wavelength. Ce-TiO2/KL is also easy to be recycled and reused.