Preparation Of TiO_2-xN_x Photocatalyst With The Visible Light Absorbance And Studies On Its Properties

TiO₂-based semiconductor photocatalysis technology has been shown to be potentially advantageous for environmental protection as it may lead to complete mineralization of pollutants at ambient conditions with the use of ultraviolet light as the energy source. However, the titanium dioxide powder stimulated by 3.2eV of ultraviolet light as an effective photocatalyst for large scale application was limited because ultraviolet radiation accounted for less than 5% within the whole solar light region.The non-metal doped into titania lattice is an effective way to improve the titania property for visible light response. However, the present methods reported is more expensive to prepare non-metal doped into titania .In this paper, the titania photocatalyst doped with nitrogen was prepared by the sol-gel method and taking urea as cheap nitrogen source. The factors influencing on preparation of titania photocatalyst doped with nitrogen were studied and optimized through decomposition of methylene blue (MB) and the formaldehyde by the orthogonal experiment; At same time , certain photocatalytic properties of the photocatalyst TiO_2-xN_x, TiO₂ and P-25 TiO₂ were compared; Then, the photocatalyst TiO_2-xN_x thin films were prepared by dipping and pulling method and the optimal condition for thin film preparation were studied by use of orthogonal experiment; The crystal type of TiO_2-xN_x powders and the surface morphological characteristic of thin films were characterized by X-ay diffraction (XRD) and atom force microscope (AFM) techniques; The photocatalytic bactericidal action of photocatalyst TiO_2-xN_x for E.coli were also investigated.The experimental results show as following:â‘ .Anatase TiO_2-xN_x crystals with 24.3nm diameter prepared by sol-gel methodcan be achieved and can decompose the methylene blue (MB) and the formaldehyde(HCHO) effectively within the visible light irradiation ,but the surface absorption properties of anatase TiO_2-xN_x crystals was inferior to the one of P-25 TiO₂ probably with low surface photocatalytic activity;...