Bismuth ferrite-graphene compounding magnetism visible light catalyst, as well as preparation method and application of same

The invention discloses a bismuth ferrite-graphene compounding photochemical catalyst with visible light responds, and a preparation method of the bismuth ferrite-graphene compounding photochemical catalyst. The catalyst prepared by the method comprises the following components according to mass percentage: 60-95% of bismuth ferrite and 5-40% of graphene. The preparation method is characterized in that the reduction of graphite oxide and the compounding of the bismuth ferrite and the graphene are finished by one step, and the catalyst prepared by the method has relatively high magnetism and good visible light responds. When the catalyst prepared by the method is used for treating methylthionine chloride solution by using visible light catalysis, a relatively good degradation effect can be obtained. Therefore, the invention has significance in the development of the visible light catalyst, and the visible light catalyst has a good application prospect when being used for sewage treatment.