摘要
The un-doped TiO2 and Cs+/Sr2+-doped TiO2 nanometer particles were prepared by sol-gel method using tetrabutyl titanate (Ti(OC4H9)4) as TiO2 precursor,and characterized with X-ray diffraction (XRD) and UV-Vis absorption spectra (UV-Vis). The photocatalytic activities of these samples were investigated by the photocatalytic degradation of methyl orange in aqueous suspension under 300 W medium pressure mercury lamp irradiation. The results show that the growth of crystallite size can be controlled effectively for the Cs+/Sr2+-doped TiO2,and crystal phase transformation of nano-sized TiO2 is retarded from anatase structure to rutile structure while using the proper doping concentration of Cs+/Sr2+. It is pure anatase of high photocatalytic activity for Cs+/Sr2+-doped nano-sized TiO2 prepared at 600 ℃ for 2 h. The average crystal sizes of un-doped TiO2,0.1% Cs+-doped TiO2 and 0.3% Sr2+-doped TiO2 are 21.3,13.1 and 10.8 nm,respectively. Moreover,the doping TiO2 can extend the light response to the visible region at 400-600 nm. By measuring their photocatalytic degradation rate of methyl orange solution,the results indicate that Cs+/Sr2+ -doped TiO2 samples are found to improve photocatalytic degradation activity of TiO2 markedly,and the optimal doping concentration is determined to be 0.1% and 0.3% for Cs+ and Sr2+,respectively. Photocatalytic degradation rate of Cs+/Sr2+-doped nano-sized TiO2 can be 15%-25% higher than that of un-doped TiO2 under the same condition.
The un-doped TiO2 and Cs+/Sr2+-doped TiO2 nanometer particles were prepared by sol-gel method using tetrabutyl titanate (Ti(OC4H9)4) as TiO2 precursor,and characterized with X-ray diffraction (XRD) and UV-Vis absorption spectra (UV-Vis). The photocatalytic activities of these samples were investigated by the photocatalytic degradation of methyl orange in aqueous suspension under 300 W medium pressure mercury lamp irradiation. The results show that the growth of crystallite size can be controlled effectively for the Cs+/Sr2+-doped TiO2,and crystal phase transformation of nano-sized TiO2 is retarded from anatase structure to rutile structure while using the proper doping concentration of Cs+/Sr2+. It is pure anatase of high photocatalytic activity for Cs+/Sr2+-doped nano-sized TiO2 prepared at 600 ℃ for 2 h. The average crystal sizes of un-doped TiO2,0.1% Cs+-doped TiO2 and 0.3% Sr2+-doped TiO2 are 21.3,13.1 and 10.8 nm,respectively. Moreover,the doping TiO2 can extend the light response to the visible region at 400-600 nm. By measuring their photocatalytic degradation rate of methyl orange solution,the results indicate that Cs+/Sr2+ -doped TiO2 samples are found to improve photocatalytic degradation activity of TiO2 markedly,and the optimal doping concentration is determined to be 0.1% and 0.3% for Cs+ and Sr2+,respectively. Photocatalytic degradation rate of Cs+/Sr2+-doped nano-sized TiO2 can be 15%-25% higher than that of un-doped TiO2 under the same condition.
基金
Project(09C1014) supported by the Research Foundation of Education Bureau of Hunan Province,China
Project(2006180) supported by the Key Discipline (Environmental Sciences) Construction Program of Hunan Province,China
