PVP-Assisted Synthesis Of Ag/AgBr/TiO₂Nanostructures And Their Visible Light Catalytic Property

Development and use of high efficiency and low-cost photocatalyst has became the cutting-edge issues at governance of organic pollution. Ag/AgBr/TiO2nanocomposite via a sol-gel process in the presence of polyvinylpyrrolidone (PVP) at room temperature. PVP not only regulated the sol-gel process, ensuring the generation of small sized particles with good dispersion, but also reduced Ag+to Ag particles and formed Ag/AgBr/TiO2noble metal-sensitizer-semiconductor ternary assemblies. The photocatalytic activity of the Ag/AgBr/TiO2nanocomposites was studied based on the degradation of rhodamine B (RhB) aqueous solution. The results showed the molar ratio of n(AgBr)/n(TiO2) and n(AgN03)/n(KBr) had directly influenced the photocatalytic activity of as-synthetic product. Moreover, we found the calcination temperature, time and the type of surfactant also can influenced the photocatalytic activity. After six cycles, the photocatalytic activity of the products kept nearly unchanged, illustrating their high stability under visible light. We found that the amorphous TiO2into anatase and rutile mixed structure was a key with the result that Ag/AgBr/TiO2photocatalyst activity increased greatly. AgBr was the light active ingredient in the three component, and it absorbed the photon to generate electron-hole pairs and induced reaction; electron injection TiO2conduction band, yield the H2O2oxidizing species, lead to the decomposition of RhB. Metallic Ag not only trapping electronic to protecte the AgBr, but also promoting the interfacial charge transfer to improve the photocatalytic activity of TiO2The advantages of this study include:1) first used PVP as a reductant directly perpared Ag/AgBr/TiO2ternary photocatalyst at room temperature.2) one step synthesis of Ag/AgBr/TiO2ternary photocatalyst without visible light or UV irradiation, and the content of each component can be simply controlloed by the reactant molar ratios. The method was simple, mild, low cost and easy to amplify production.PVP-assisted one step synthesis of Ag/AgCl/Cu2O ternary nanocomposite at room temperature. The SEM of Ag/AgCl/Cu2O photocatalyst was hollow cube structure of different size, the cube some was rough and another was smooth of the the six surface, but the surface of each cube has a hole. We found the temperature can influenced the photocatalytic activity.