The Preparation Of Cerium-doped TiO₂ Films By Magnetron Sputtering And Research On Photocatalytic Ability

As a stable wide band gap semiconductor, TiO2 play an important role in many areas, especially its photocatalytic has become a hot research in recent years. But as a photocatalyst, TiO2 has its own limitation which summed up is:don't absorb visible light and high electron-hole recombination rate. To solve the problem, some studies improve the photocatalytic of TiO2 by Ce-doped, but it's fabricated mostly by the sol-gel method. But the TiO2 film made by sol-gel have poor adhesion with the substrate, affected the practical application of TiO2 greatly. Thinking of this, we fabricate the Ce-doped TiO2 by magnetron sputtering. We found that the Ce-doped titania films extend the range of visible light absorption and shows a better photocatalytic activity though the characterized and test.Magnetron sputtering method has the advantage as follows:films fabricated by it are compact, uniform, good adhesion with the substrate and has achieved industrialization.In this paper, we prepared the Ce-doped TiO2 film at room temperature by the magnetron sputtering, and studied the structure, properties, and photocatalytic of films. In addition, some parameters of the film which affect the photocatalytic also studied. Finally we made some inquiry to N, Ce co-doped TiO2.The first chapter introduces the structure,properties and uses of TiO2 and CeO2, then the research progress of Ce-doped TiO2 film was introduced. Finally we elaborated the content of research.The second chapter describes the experimental equipment and the testing equipment. Firstly, we made the TiO2 target with different ratio of CeO2, then we prepared the Ce-doped TiO2 film on quartz glass by the magnetron sputtering. By the X-ray diffraction, UV-visible spectrophotometer, X-ray photoelectron spectroscopy, fluorescence spectroscopy and other analysis equipment, we studied the structure, optical properties and photocatalytic of different films.The third chapter introduces production process of the doping target firstly, then we prepared the Ce-doped TiO2 film in the magnetron sputtering system. XRD analysis showed that the XRD spectrum of doping films are structure of the integrated embodiment for TiO2, CeO2 and Ce2O3 crystal. The transmittance of TiO2 film with different Ce-doped show that:with the increase of cerium-doped, films'Eg appeared red-shift from the 3.29eV decreases to 2.67eV, the visible light absorption was enhanced. XPS analysis of 5% Ce-doped films showed that some of the Ti4+ converted to Ti3+, and most of the Ce4+ converted into Ce3+. Though the photoluminescence spectroscopy, we found that the Ce-doped TiO2 films don't show the new emission peak, but the light intensity decreased. Finally, we test the photocatalytic properties of Ce-doped TiO2 films with different cerium ratio, the results showed that the 5% Ce-doped TiO2 film show a best photocatalytic ability.In the chapter 4, we studied how the thin film parameters such as, thickness and annealing temperature affect the optical absorption and photocatalytic of TiO2 film. At last we found that the parameters which affect the photocatalytic of TiO2 film is not single, it's a comprehensive result of various factors interact.In the chapter 5, all the work was summarized. Finally the future research and application of Ce-doped TiO2 film were discussed.