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Zn-doped TiO_2 catalysts were prepared using a sol-gel method and characterized by XPS,UV-Vis,BET, XRD in this study.Under the irradiation of simulant sunlight,the photocatalytic activity for the degradation of p-nitrophenol was studied too.After irradiation for 2.5 h,the degradation percentage of p-nitrophenol could rise to more than 80%.The results showed that the spectrum absorption band edge of Zn/TiO_2 powder does not broaden obviously comparing with pure TiO_2 powder.Zinc exists as Zn (Ⅱ).When calcined at 973 K,there is a new phase as ZnTiO_3 in Zn/TiO_2 catalyst.The order of photocatalytic activity of Zn/TiO_2 catalysts calcined at different temperatures for p-nitrophenol is 773 K＞673 K＞873 K＞573 K＞973 K and the photocatalytic activity of Zn/TiO_2 catalyst cal- cined at 773 K is better than TiO_2 catalysts heated at the same temperature,and outclasses that of commercial TiO_2 catalyst.It also showed that the photocatalytic degradation of p-nitrophenol follows first-order kinetics under the irra- diation of simulant sunlight.
Zn-doped TiO 2 catalysts were prepared using a sol-gel method and characterized by XPS, UV-Vis, BET, XRD in this study. Under the irradiation of simulant sunlight, the photocatalytic activity for the degradation of p-nitrophenol was studied too. After irradiation for 2.5 h, the degradation percentage of p-nitrophenol could rise to more than 80%. The results showed that the spectrum absorption band edge of Zn / TiO_2 powder does not broaden obviously compared with pure TiO_2 powder. Zinc exists as Zn ( Ⅱ) .When calcined at 973 K, there is a new phase as ZnTiO_3 in Zn / TiO_2 catalyst. The order of photocatalytic activity of Zn / TiO_2 catalysts calcined at different temperatures for p-nitrophenol is 773 K> 673 K> 873 K> 573 K> 973 K and the photocatalytic activity of Zn / TiO 2 catalyst cal- cined at 773 K is better than TiO 2 catalysts heated at the same temperature, and out of classes that of commercial TiO 2 catalyst. It also showed that the photocatalytic degradation of p-nitrophenol follows first-ord er kinetics under the irra- diation of simulant sunlight.