Photocatalytic activity of lanthanum doping TiO2

The photocatalytic activity of the mixtures of TiO₂ with the rare earth oxide La was investigated. The study on the effect of the rare earth oxide content, calcinating temperature and calcinating time on the performance of the mixture revealed that sample treated under higher temperature and longer time had higher photoactivity than pure TiO₂. The experimental results of polycrystalline X-ray diffraction showed that the extent of the lattice expansion varied with the variation of calcinating temperature of time. It is suggested that this might be due to the variation of La content diffused into the TiO₂ lattice. The La in the lattice may inhibit the recombination of photogenerated electron-hole pairs and thus enhance the photoactivity.