Main Article Content

Abstract

In order to improve the visible light response and reaction efficiency of nitrogen-doped TiO2, urea is used as nitrogen source and silica gel as load agent. Sol-gel method is used to prepare powder of nitrogendoped TiO2 supported on SiO2 and then by incipient-wetness impregnation method to load MnO2 on catalyst, after drying, roasting to prepare the composite photo-catalyst. The prepared composite catalysts were characterized by XPS, TEM, SEM, XRD and other methods. Moreover, the photo-catalytic activity of the composite catalysts under visible-light region were tested and the influences of nitrogen content and calcinations temperature on the photo-catalytic activity were investigated. The results showed that (1) the modified composite catalyst light response range from UV to visible-light region, which results in a high visible-light photo-catalytic activity in the degradation of methyl orange. (2) Through the mechanism of photo-catalytic reaction and the treatment effect analysis, MnO2 as catalytic resulting O2 can serve as a good electronic capture agent and improve the efficiency of reaction. (3) With the reduction of nitrogen content, and the increase in calcinations temperature, the visible-light photo-catalytic activity weakens. (4) The activity of catalyst was reused for six times, did not significantly reduced and has excellent efficiency and stability.

Keywords

TiO2 Nitrogen-doping MnO2 SiO2 Urea Visible light catalytic

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