Preparation And Characterization Of Lanthanum-doped Titanium Dioxide Nanoparticles And Photocatalytic Properties

In this thesis, we adopted La-doped and La/Cu together doped modification method to improve the photocatalytic activity of titanium dioxide (TiO₂) photocatalysts. The La and La/Cu together doped TiO₂ nanocatalsts were prepared by sol-hydrothermal method, the influence of quantities of doped and calcinating temperature on the activity of catalysis was investigated principal. And the XRD, PL, and SPS methods characterized the mechanisms of modification. The results indicated that the doping of La inhibited the phase transformation of TiO₂. And the photocatalytic activity of samples was improved through suitable doping quantities and calcinating temperature, which was in agreement with the results of characterization, i.e. the more intensity of SPS signal of samples, the more intensity of spectrum, the more photocatalytic activity. It indicated that compose and crystallinity of the TiO₂ crystalline phase had a predominant effect on the photocatalytic activity of samples. It was shown that the photocatalytic activity of TiO₂ catalysts that were prepared by sol-hydrothermal method was better than that prepared by sol-gel method from the comparison investigations of sol-hydrothermal and sol-gel methods, which result in the better dispersiveness of the former.In the La/Cu complex doped and modification processes, there wasn't remarkable cooperation effect between the two modifying agents, and the photocatalytic activity was improved unremarkable of our experiments.It was confirmed that the activity of TiO2 photocatalysts could be estimated by the preliminary testing of SPS and FS methods.