Study On The Perparation And Propertise Of New Photocatalyts

TiO₂ has been widely studied in the treatment technology for environmental pollutants.The band gap width of TiO₂ is 3.0-3.2 eV,so wide band gap width makes its conduction electron have certain reduction capability,and the hole of valence band has strong oxidation ability.However,due to its wide bandgap width,the absorption of TiO₂ can only in UV light region,which hinders the actual application of TiO₂.There are several ways to improve the photocatalytic activity of TiO₂:reduce the size of the catalyst,doping transition metal ion or precious metals,doping non-metallic ion,photosensitization,mixed semiconductor materials,preparation pore structure.This study we synthesized the heterojunction photocatalyst with TiO₂ to improve the performance photocatalysis of TiO₂.We prepared two photocatalysts with visible light activity of and their catalytic properties were studied by degradation of decabromodiphenyl ether?BDE209?.1.A series of x-g-C₃N₄-TiO₂ composite photocatalytic materials with different contents of g-C₃N₄ were prepared by sol-gel method.The properties of catalysts were characterized by UV-Vis,X-ray diffraction?XRD?,and X-ray photoelectron spectroscopy?XPS?.The photochemical reduction method for the degradation of BDE209 by x-g-C₃N₄-TiO₂ under visible light was studied,and the kinetics of the photocatalytic degradation of BDE209 with visible light by the catalyst under different conditions were investigated.The results showed that the degradation rate of BDE209 with x-g-C₃N₄-TiO₂ was 15 times higher than that of with the pure g-C₃N₄ as catalyst.2.A series of x-AgI-TiO₂ with different content of AgI were prepared by the co-precipitation methold.The properties of the catalyst were characterized by UV-Vis,XRD and XPS.The degradation of BDE209 with x-AgI-TiO₂ under visible light were studied under different conditions.Product analysis showed that the degradation process of BDE209 is different from that of TiO₂;it was a multi-electron reduction mechanism.