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Mesoporous TiO2 materials have great application values in wastewater treatment and air purification because of its high photocatalyti properties.However,Mesoporous TiO2 photocatalyst has lower quantum yield and lower visible—light utilization ratio.To this problem,in this paper,advantages and disadvantages of mesoporous TiO2 photocatalyst which was prepared by hydrolysis precipitation method and Sol-Gel method we compared.Mesoporous TiO2 photocatalyst was prepared by hydrolysis precipitation method and doped modification.It put forward one-element or two-element doped modification method to improve the property of mesoporous TiO2 photocatalyst with transition metal ions as doping agent or rare earth ions.T crystal phase,microstructure,photocatalytic properties of the prepared mesoporous TiO2 were characterized by X—ray diffraction(XRD),N2 adsorption-desorption isotherm,transmission electron microscopy(TEM),Ultraviolet—Visible absorption spectrum,infrared spectrum.The influences of doped other ions to microstructure and properties of Mesoporous TiO2 were investigated.The photocatalytic properties of mesoporous TiO2 in the degradation of methyl orange solution were determined.The effect of different molar ratio of doped agent,heat treatment temperature and concentrations of TiO2 to properties of one-element or two-element doped mesoporous TiO2 were also studied.The photocatalytic properties of mesoporous TiO2 were improved.The effect of different doped elements was investigated in the one--element or two-element doped system.The results showed that after heat treatment temperature at 500℃ tetragonal anatase phase structure was formed in the mesoporous TiO2 photocatalyst which was prepared by hydrolysis precipitation method or Sol—Gel method.And the temperature(500℃)was considered the best heat treatment temperature of the mesoporous TiO2.The optimal concentration of the mesoporous TiO2 was .0 g-L-1.Photocatalytic decomposing rate of methyl orange solution were 100%and 90%respectively.Before and after heat treatment,the photo absorption performance of mesoporous TiO2 was measured by Ultraviolet—Visible absorption spectrum,and the bondings in mesoporous TiO2 and the changes were discussed by infrared spectrum.It indicated that absorption wavelength range of mesoporous TiO2 was obvious redshift after he treatment.Absorption area was obviously increased in the visible region.Solar energy utilization efficiency was significantly improved.One-element(Co,Fe or Ce)doped mesoporous TiO2 photocatalyst were prepared respectively by hydrolysis precipitation method.The particle size and phase transformation process of one-element doped mesoporous TiO2 were controlled by changing heat treatment temperature.The one—element doped mesoporous TiO2 possesses high specific surface area,high purity,narrow pore size distribution and high thermal stability.The best heat treatment temperature of the mesoporous TiO2 was 500℃.The optimal concentration of the doping agent were 0.1,0.05 and 0.05 mol% respectively.Photocatalytic decomposing rate of methyl orange solution were up to 90,99 and 94%respectively.
Two-element(Co,Ce)doped mesoporous Ti photocatalyst was prepared by hydrolysis precipitation method.The particle size and phase transformation process of(Co,Ce)doped mesoporous TiO2 were controlled by changing heat treatmenttemperature.(Co,Ce)dop mesoporous TiO2 was high thermal stability.The best heat treatment temperature of the mesoporous TiO2 was 500℃.The optimal concentration of the doping agent was 0.1 Comol%and O.05Cemol% respectively.Photocatalytic decomposing rate of methyl orange solution was up to 90%.In th paper,Mesoporous TiO2 nano-powder was successfully obtarined by tetrabutyl titanate as raw materials and one—element or two-element were doped in the mesoporous TiO photocatalyst.The thermal stability and photocatalystic properties of mesoporous TiO2 nano-powder increased obviously.