| In recent years, it has attracted a great deal of attention that how to improve the photocatalytic activity of TiO2 and prepare the films which possess high photocatalytic activity and supre-hydrophylicity. In this thesis, Ti02 series thin films which have different structure and different composition were prepared by magnetron sputtering and sol-gel method. The structures and properties of these films were researched, and the product technologies of super-hydrophilicity were also preliminary studied. The results are as follows:1. The effects of B plus voltage, sputtering time, anode current and the target character on the TiO2 crystal form, particle size, thickness, aspect, photocatalytic activity, hydrophilicity of TiO2 film which prepared by magnetron sputtering were studied. The sputtering conditions and the film parameters were optimized and the technology for preparing TiO2 films which have high photocatalytic activity and super-hydrophilicity was obtained, that are as follows:(1) B plus voltage is 1.8kV; sputtering time is 60min; the target parameters are: 100% anatase TiO2, the thickness is 9mm, the diameter is 53.5mm, the quality is 34.92g and the density is 1.726g/cm3; anode current is Imax/4. The contact angle for water of the film which prepared according to above conditions is 4?(2) B plus voltage is 1.2kV; sputtering time is 80min; the target parameters are: 100% anatase TiO2, the thickness is 6.5mm, the diameter is 53.5mm, the quality is 24.99g and the density is 1.71g/cm3; anode current is Imax. The constant of reaction kinetics of the film which prepared according to above conditions for degrading methyl orange is 0.0192.2. Doping TiO2 film, composite TiO2 film, stromatolith TiO2 film and composite stromatolith TiO2 film were prepared by sol-gel method. The prepared technology and the properties of TiO2 series films were studied. The results indicate:(1) The photocatalytic activity and hydrophilicity of TiO2 film are affected by the factors of thickness, porosity and heat-treated temperature which lead to the changes of thehydroxyl content, adsorbability and surface roughness of the film.(2) Doping a little of Ag to TiO2 film is good for increasing the content of hydroxy and bridging oxygen on the film surface, and improving the photocatalytic activity and hydrophilicity. But the hydrophilicity decreases as the doping Ag increases to a certain content. The surface bridging oxygen has a larger impact on the film hydrophilicity than the hydroxy. But the latter has more impact on the photocatalysis than the former.(3) The photocatalytic activity and hydrophilicity of the composite films, stromatolith films and composite stromatolith films that composed of TiO2 and SnO2 are superior to pure TiO2 film. As to TiO2-SnO2 composite films, the photocatalytic activity is the best as the mole content of SnO2 is about 10%, and the hydrophilicity is the best as the mole content of SnO2 is about l%-5%. As to the stromatolith film and composite stromatolith film of TiO2 and Sn02, the photocatalytic activity of the film which TiO2 is on the surface layer is better than that of the film which SnO2 is on the surface layer. The reason for the above phenomenon is that the structure of the former is good for the separation of the electron and positive hole which are photo-induced on the surface layer TiO2 and results in the enhancement of the photocatalytic activity.(4) The photocatalytic activity TiO2-Fe2O3 composite film is superior to that of pure TiO2 film as the content of Fe2O3 is lower which attribute to the separation of photo-induced carriers between in the semiconductors having different energy level. The photocatalytic activity is the best as the mole content of Fe2O3 is about 0.5%, and the hydrophilicity is the best as the mole content of Fe2O3 is about 0.05~0.1%. But the photocatalytic activity and hydrophilicity of the stromatolith and the composite stromatolith films of TiO2 and Fe2O3 are not good because the recombination rate of photo-induce...
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