Preparation Of Fe₃O₄Nanoparticles And SnO₂/Fe₃O₄Photocatalyst And Research On Photocatalytic Property Of SnO₂/Fe₃O₄

SnO2is a new-type photocatalyst and Fe3O4is a magnetic material. It must be of great significance if the SnO2/Fe3O4can be made. In this paper, The Fe3O4was prepared by different methods and the SnO2was coated on the surface of Fe3O4. The results were summarized as follow:(1) The preparation of Fe3O4nano-particles:the Fe3O4nano-particles were prepared by both co-precipitation and hydrothermal methods. The factors which influenced the experimental results such as reactant ratio, drying temperature, pH, surfactant, hydrothermal reaction temperature, hydrothermal reaction time were studied. The results showed that the optimum process conditions by co-precipitation methods:n(Fe2+):n(Fe3+):n(OH-)=1:1:6, drying temperature(80℃), pH(8-9); the optimal process conditions by hydrothermal methods: n(Fe2+):n(Fe3+):n(OH-)=:1:1:6, hydrothermal temperature(180℃), optimum reaction time(6h). The dispersibility of Fe3O4can be improved by surfactant, the size of Fe3O4was almost20nm-50nm and the shape was spherical and square.(2) The preparation of SnO2/Fe3O4catalyst:the results showed that the optimum process conditions by co-precipitation methods:n(Fe3O4):n(Sn4+)=1:2, pH(8-9), heat treatment temperature(600℃), reaction time(6h); the optimal process conditions by hydrothermal methods:n(Fe3O4):n(Sn4+)=1:2～1:4, hydrothermal temperature(180℃), hydrothermal time(12h). There was only some SnO2coated on the surface of Fe3O4but not much, the comprehensive performance of SnO2/Fe3O4synthesized by hydrothermal was better.(3) The performance test of SnO2/Fe3O4catalyst:some factors which effected the photocatalytic efficiency were researched by degrading methyl orange solution. The results were showed as below:the catalytic performance of SnO2Fe3O4catalyst synthesized by both methods was not high; some factors can cause certain effect to catalytic activity, such as the concentration of methyl orange, the concentration of catalyst, reaction time, the conditions of illumination, the concentration of OH-. The SnO2/Fe3O4can be recycled due to the magnetic property of Fe3O4for a certain number of times.