溶胶-凝胶法制备TiO_2/MCM-41负载型光催化剂及其性能表征

Preparation and characterization of TiO_2/MCM-41 loaded photocatalyst by sol-gel method

以钛酸丁酯为钛源、MCM-41分子筛为载体,采用溶胶-凝胶法制备TiO2/MCM-41负载型光催化剂,并通过XRD、BET、TEM、XPS对最佳条件下制备的光催化剂进行表征。结果表明,所制光催化剂是一种具有均匀规则孔道结构的介孔材料,其粉体比表面积高达358.8m2/g;经700℃煅烧,催化剂主要晶相为锐钛矿相。光催化剂中的Ti以+4价存在,TiO2表面羟基氧所占比率为38.0%。以水中甲基橙为模拟污染物,TiO2/MCM-41光催化剂对浓度为25mg/L的甲基橙溶液降解0.5h后,其脱色率为93.7%。

A loaded photocatalyst,TiO2/MCM-41,was prepared by the sol-gel method using titanate butyl acetate as the titanium source and MCM-41 molecular sieve as the carrier.The optimal photocatalyst was characterized by XRD,BET,TEM and XPS.The results show that the photocatalyst is a mesoporous material with the surface area at 358.8 m2/g and regular structure.At the calcination temperature of 700 ℃,the main crystalline phase in photocatalyst is still anatase phase.XPS analysis indicates that titanium exhibits ＋4 valence,and the percentage of hydroxyl oxygen on TiO2 surface is 38.0%.With 25 mg/L aqueous solution of methyl orange,the decolorization rate of methyl orange reaches 93.7% under 0.5 h UV irradiation.