Ag掺杂的K_2La_2Ti_3O_(10)可见光催化制氢的研究

Photocatalytic activity of Ag-doped K_2La_2Ti_3O_(10) under visible light irradiation for hydrogen evolution

采用高温固相法合成了具有可见光响应的Ag掺杂的K2La2Ti3O10催化剂,利用XRD、UV-VisDRS、TEM和XPS对催化剂进行了表征。考察了催化剂的可见光催化分解甲醇水溶液制氢的活性,并对可见光催化机理进行了分析。研究表明,Ag的掺杂没有改变K2La2Ti3O10的微晶结构,并使催化剂粒径有所减小。紫外-可见漫反射分析表明禁带宽度为2.8eV左右,对可见光具有较高吸收。担载2%(质量分数)Pt后,在可见光下光催化活性较K2La2Ti3O10大大提高,掺杂1%(摩尔分数)Ag的K2La2Ti3O10的产氢量为0.37mmol,而纯K2La2Ti3O10的产氢量只有0.037mmol;掺杂1%(摩尔分数)Ag的K2La2Ti3O10的产氢速率最大0.08mmol/h。

In this paper,Ag-doped K2La2Ti3O10 and pure were prepared by high temperature solid state reaction and were characterized by XRD,UV-Vis DRS and TEM.The photocatalytic activities of the catalysts for hydrogen evolution were carried out under visible light irradiation.The results showed that the Ag-doped K2La2Ti3O10 powder shifts the UV absorption band of K2La2Ti3O10 toward visible light region.The Ag-doped K2La2Ti3O10 shows a higher activity than K2La2Ti3O10 under visible light irradiation after they were loaded with 2wt% Pt as co-catalysts.The highest activity is obtained with 0.08mmol/h when K2La2Ti3O10 doped with 1mol% of Ag ion to La.