The Preparation and Evaluation of TiO2 Series Materials for Environmental Purification

The Preparation and Evaluation of TiO2 Series Materials for Environmental Purification
　　human is facing increasingly industrial organic pollutants,air purification and other environmental problems,which is a serious threat to human health and quality of life.TiO2 Photocatalytic materials have large spectrum and bactericidal Performance,under the light, non-selectively oxidize(degrade) various organics and make them completely mineralize. Various pathogensin can be killed.Significant application prospects have been shown in water purification and treatment,indoor air purification and so on.Because of the efficiency,no secondary pollution strong magnets and direct use of solar energy, photocatalytic-oxidation technology attracts the research’s attention,but TiO2 only takes advantage of uitraviolet ray.The ultilization of visible light is very low.So technology of changing.TiO2’s cuality has been in the hot pot in recent years.TiO2 photocatalytic composite materials doped by Ce3+,Ce3+/Y3+ and La3+/Y3+ has been produced by sol-gel process based in the raw material of TNB.
　　In this thesis,several factors have been probed intensively,namely:doping effect on grain size,crysta microstructure of titanium dioxide and the photocatalytic degradation of the target of methylene blue solution under the violent.The effects of TiO2 photocatalytic properties by different elements and quantity of doping are also studied.It has been shown that using oxides can modify the band gap or act as charge separators of the photoinduced electron-hole pair thus enhance the http://www.chinamagnets.biz photocatalytic activity. Introduction of defects location or change of crystallinity in TiO2 lattice can effectively inhibit the resume between electron and hole,and transmission of the carrier can be happened in different energy level semiconductor and separated between the carrier effectively,extend life of carrier,thus raising the photocatalytic activity of TiO2.Through the control of synthesis conditions,Product characteristics can be controlled.So we can get the best photocatalyst preparation technology.Now the catalyst samples for the degradation of methylene blue solution have the highest catalytic efficiency.The valuable experimental data has been provide for new preparation method of TiO2 and high usage ratio of solar.It also has been provided referential value for the selection of wastewater treatment technics.