纳米二氧化钛薄膜光催化剂的合成及特性

研究采用溶胶-凝胶技术以载玻片为基质制备了纳米TiO2薄膜,向溶胶中添加乙酰丙酮后改善了溶胶的稳定性及薄膜的牢固性。用扫描探针显微镜(DFM)、X射线衍射(XRD)、红外光谱(IR)及X射线光电子能谱(XPS)对薄膜进行了表征。结果表明:扫描探针显微镜(DFM)观察到薄膜中颗粒的粒径为20~40nm,X射线衍射(XRD)表明TiO2为锐钛型,用红外光谱(IR)表征了溶胶及粉末样品的物性并探讨了反应的机理,X射线光电子能谱(XPS)结果显示薄膜中除含有Ti、O元素外,还有少量从玻璃表面扩散至薄膜中的Na和Si元素。TiO2薄膜对光降解甲基橙水溶液具有很好的光催化性,通过掺SnO2、酸处理途径明显提高了其性能。

Preparation and Characterization of Nanosized TiO2 Films as Photocatalysts

Transparent titanium oxide (TiO2) thin films on soda-lime glass substrates were prepared by using sol-gel method. The stability of precursor solution and the fixation of the titanium oxide film on substrates were improved by adding acetyl aceton in sol. Films of titanium oxide were characterized by different techniques like DFM, XRD, IR and XPS. The particles forming the titanium oxide films deposited by this technique are in the size of 20~40 nm and in anatase structure. The mechanism of reaction was discussed according to IR results of sol of titanium oxide as well as the dried powder of titanium oxide. XPS results of films show that, besides Ti and O elements, there is a small amount of sodium and silicon from the glass substrate. The titanium oxide films were found to be very active for photocatalytic decomposition of methyl orange aqueous solution and the photocatalytic activity of films was improved with SnO2-doped and acid treatment of films.