溶胶-凝胶制备工艺对TiO_(2)薄膜光催化性能的影响

EFFECTS OF PREPARATION PROCESS ON PHOTOCATALYTIC ACTIVITY OF TiO_(2) FILMS BY SOL-GEL METHOD

采用溶胶-凝胶工艺制备纳米TiO_(2)溶胶,并通过旋涂法制备高效光催化TiO_(2)薄膜。研究络合剂、pH值和焙烧温度对TiO_(2)薄膜光催化性能的影响。络合剂能有效抑制钛酸丁酯水解速率,双络合剂制备的薄膜具有更强的光催化性。pH值能影响钛酸丁酯的水解和薄膜表面介孔结构的生长。焙烧温度决定TiO_(2)晶型和尺寸,同时对薄膜表面粗糙度和光学特性有重要影响。高效光催化TiO_(2)薄膜的最佳制备工艺为以pH值为6、双络合剂制备的溶胶为原料,旋涂后在500℃条件下焙烧3 h。

Nano TiO_(2)sols are prepared by the sol-gel method,and high photocatalytic TiO_(2)films are deposited by spin-coating technology.The effects of pH value,complexant and calcination temperature on the photocatalytic activity of TiO_(2)films are studied in this paper.Complexant can effectively inhibit the hydrolysis rate of butyl titanate.The sols prepared by double-complexant have better stability and the corresponding films obtain higher photocatalytic activity.pH value can affect the hydrolysis rate of butyl titanate.Besides,it has a critical influence on the size of holes in the film surfaces.When pH value is 6,the film surface is covered with microNano holes.The calcination temperature determines the structure and size of TiO_(2)particles,it also affects surface roughness and optical properties of TiO_(2)films.The optimal process for preparing high photocatalytic TiO_(2)films is firstly to prepare Nano TiO_(2)sols with doublecomplexant and to adjust the p H of the sols to 6,followed by spin-coating with a spinning coater and calcination at 500℃for 3 hours.