采用溶胶-凝胶法制备了系列Ru/TiO2和Ru/TiO2/SiO2可见光活性光催化剂。通过TEM、XPS、XRD、UV-Vis漫反射和电化学对样品进行了表征。发现Ru和Si的存在可以抑制TiO2的相转变和晶粒生长;Ru掺杂使TiO2和TiO2/SiO2对可见光的吸收增强,也提高了光生电子和空穴的分离,因而,提高了催化剂可见光分解水制氢活性。当Ru在TiO2和TiO2/SiO2中的掺杂量分别为0.014%和0.021%(质量分数)时,光催化剂的可见光活性最高,且Ru/TiO2/SiO2活性为Ru/TiO2的5倍。
A series of photocatalysts with visible light activity,Ru/TiO2 and Ru/TiO2/SiO2 were prepared by sol-gel method,and characterized by SEM,XPS,XRD,UV-Vis DRS and electrochemistry.It was found that the phase transfer and the grain growth of TiO2 were inhibited by doping Ru and Si.The absorption intensity to visible light and the separation of photo-generated electrons and holes of Ru doped TiO2 and TiO2/SiO2 was promoted so that the activity of hydrogen generation from water increased under visible light irradiation.When doping content of Ru was 0.014wt% in TiO2 and 0.021wt% in TiO2/SiO2 respectively,the photocatalysts exhibited the highest photocatalytic activity under visible light irradiation.The activity of Ru/TiO2/SiO2 was 5 times as high as that of Ru/TiO2.