Preparation optimization of La3+ Doped TiO2 powder by chemical precipitation

La3+ doped TiO2 powder was prepared by chemical precipitation and the technique was optimized by an orthogonal experiment. The morphology, structure and light absorption properties of TiO2 powders were characterized by SEM, XRD, XPS and UV-Vis. The results show that the effect of the calcinating temperature and the amount of La3+ on optical absorption properties of TiO2 is significant. The main crystal structure of La3+ doped TiO2 powder at different calcinating temperatures is anatase. Higher calcinating temperature can enhance the absorption intensity of La3+ doped TiO2 in the UV band. Doping La3+ can improve agglomeration of TiO2 powder and narrow the band gap of TiO2. In addition, a certain amount of hydroxyls are also adsorbed on the surface of TiO2 due to La3+ doping. The optimal preparation conditions of La3+ doped TiO2 powder are as follows: the calcinating temperature 800℃, the amount of La3+ 0.6 mol%, the solution temperature 90℃, and the pH value 8.0. TiO2 powder prepared under the above conditions has the optimal visible light property. © 2015, Science Press. All right reserved.