Preparation and characteristics of RE (Pr, Nd, Sm, Eu, Dy) doped TiO_2 photocatalytic films
LIU Kuiren YU Huiwen HAN Qing WEI Dezhou School of Materials & Metallurgy, Northeastern University, Shenyang 110004 School of Resources & Civil Engineering, Northeastern University, Shenyang 110004
Doping with five rare earth elements(Pr, Nd, Sm, Eu and Dy) respectively, a series of TiO2 films were prepared by sol-gel process. Based on the photodegradative ratio of Rhodamine B, the effects of RE doping amounts, the number of film coatings, the roasting temperature and the roasting time on the photocatalytic activity were investigated, and the respective optimum conditions for preparing the five types of RE doped TiO2 films mentioned above were obtained. All these films, on which there exists large amount of defects, contain only TiO2 but no any rare earth oxides and their structures are less anatase and more rutile phase, except that Pr-doped TiO2 is completely composed by rutile phase. Among these RE doped Ti02 films, the highest photocatalytic activity is obtained by Eu-doped TiO2 film since the photodegradative ratio of Rhodamine B is 89.3%. Comparing with pure TiO2 film, rare earth doping significantly increases the photocatalytic activity due to the higher response to visible light.