TiO_2/SnO_2复合薄膜光诱导超亲水性机理的XPS研究

XPS study on mechanism of photo-induced super-hydrophilicity of TiO_2/SnO_2 composite film

利用X射线光电子能谱仪对用溶胶-凝胶法制备的TiO2/SnO2复合薄膜的表面化学状态进行分析,结果表明:热处理及紫外光照前后,薄膜表面的化学状态均发生了变化,薄膜表面的碳氧或过氧化物基团增加,这些基团具有较强的活性,通过氢键和水中的极性基团作用,产生超亲水性。此外,掺杂SnO2提高了TiO2/SnO2复合薄膜的表面能,改变了薄膜表面的化学结构,使TiO2薄膜获得了较好的亲水性能和催化活性。

X-ray photoelectron spectroscopy（XPS）is used to determine the surface chemical states of TiO2/SnO2 composite thin-films which were prepared on soda-lime glass with sol-gel method. The results show that the surface chemical states of TiO2/SnO2 composite thin-films have changed after heat-treatment and UV illumination, and that a great deal of oxygen-containing groups or peroxides are produced on TiO2 thin-film surface. Oxide active groups, generated during this process, react with polar groups in water by hydrogen bonds and lead to super-hydrophilicity. In addition,the doping of SnO2 into TiO2 can enhance surface energy and change the surface chemical structure of TiO2/SnO2 composite thin films, which make thin-film gain better hydrophilicity and higher photocatalytie activity.