Synthesis, Characterization And Application Of Nanosized TiO₂-ZnO

Photocataly which has been studied recently is a new function material for environmental protection. But the ordinary semiconductor photocatalyst using for environmental protection has no reaction to visible light. They only can be reacted by the ultraviolet radiation. Because less then 5% of the sun spectrum is ultraviolet radiation and 43% is visible light. We must made the effective visible light reaction photocatalyst to speed the reaction. Enlarge the reactive spectrum and improve the usage rate of the sun light.The main work and effect in this paper are:(1)Nanometer TiO₂/ZnO photocatalyst is been prepared by homogeneous precipitation method. The condition of synthesis and the process of sinter is researched. So that the reasonable process and parameter are found . The state, size and UV—Vis absorption of the composite TiO₂/ZnO were investigated by XRD, TEM, DTA—TG and UV—Vis. The results show that the partial of composite semiconductor photo catalyst is global. The average size is about 20nm. The size of the sample is very small and the UV—Vis. Absorption is quite strong. The reaction light more from 388nm of TiO₂ to Visible light.(2)It is also found that Using sunlight as the light source, the photocatalgtic activities were investigated by the degradation of organic dye. The home—made sample's photocatalgtic degradation rate of organic dye solution and the elimination rate of COD_cr can be close to 90% after 60 min.This can say that Our home—made coupled material is more effective than pure TiO₂ and the photocatalgtic degradation reaction is a first -order reaction. The studying show us that: Nanometer TiO₂/ZnO coupled material can improve the utilization rate of the visible ray. The activity of the sample in decolorizing dye solution is better than pure TiO₂.