A mechanism for enhanced photocatalytic activity of silver-loaded titanium dioxide

被引：236
作者：
Liu, SX
Qu, ZP
Han, XW
Sun, CL [1 ]
机构：
[1] Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Catalysis, Dalian 116023, Peoples R China
[2] NE Forest Univ, Harbin 150040, Peoples R China
来源：
CATALYSIS TODAY | 2004年 / 93-5卷
关键词：
photocatalytic activity; silver-loaded TiO2; photogenerated reactive species;
D O I：
10.1016/j.cattod.2004.06.097
中图分类号：
O69 [应用化学];
学科分类号：
081704 ;
摘要：
In this paper, silver-loaded TiO2 photocatalyst was prepared by photochemical impregnation method and characterized by transmission electron microscopy (TEM), diffuse reflectance spectra (DRS), photooxidation of phenol and photoreduction of Cr(VI). Electron paramagnetic resonance (EPR) was used to detect photoproduced paramagnetic radicals. The correlation of photocatalytic activity and photogenerated reactive species was discussed, and the mechanism of silver-loaded TiO2 for enhancement of photocatalytic activity was elucidated. The results show that deposited silver on TiO2 Surface acts as a site where electrons accumulate. The better separation between electrons and holes on the modified TiO2 surface allowed more efficiency for the oxidation and reduction reactions. The enhanced photocatalytic activity was mainly attributed to the increased amounts of O-2(.-) reactive species and surface Ti3+ reactive center on silver-loaded TiO2 photocatalyst. (C) 2004 Published by Elsevier B.V.
引用
收藏
页码：877 / 884
页数：8
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