▎ 摘　　要

NOVELTY - A graphene composite titanium dioxide photocatalyst comprises magnetic nanoparticles, graphene, and titanium dioxide. Mass ratio of magnetic nanoparticles to graphene is 1:100-1:5. Mass ratio of nanoparticles, graphene and titanium dioxide is 1:1-1:20. USE - Graphene composite titanium dioxide photocatalyst. ADVANTAGE - The photocatalyst is capable of being separated and recycled magnetically. It has high catalytic performance. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included preparation of the photocatalyst which comprises: (A) preparing magnetic graphene powder, (B) preparing rutile titanium dioxide sol, and (C) preparing photocatalyst. The step (A) comprises adding graphene (10-100 mg) dispersed in alcohol solvent, and performing ultrasonic treatment for 0. 5-2 hours; adding ferric salt (0.2-1 g), stirring for 1-2 hours, adding reducing agent (1-5 g) and surface active agent (1-5 g), and stirring for 0.5-1 hours; and uniformly mixing and transferring to stainless steel reaction kettle for 10-24 to hours at 100-200 degrees C, using ethanol to wash and centrifugal separation, and vacuum drying at 50 degrees C to obtain magnetic graphene powder. The step (B) comprises mixing titanium compound (1-10 mL) and gradually adding at vol. ratio of 1:1-1:10 for reducing desulfurization solvent and acid solution; stirring until clear, adding water until total volume is 20-80 mL, and stirring for 0.5-1 hours; transferring to stainless steel reaction kettle with hydrothermal reaction under 80-200 degrees C for 0.5-1 hour; and using deionized water to wash and centrifugal separation, and adding mixed solution of water and ethanol to obtain rutile titanium dioxide sol. The step (C) comprises dipping magnetic graphene in rutile titanium dioxide sol-gel, stirring for 0. 5-2 hours, rotating evaporating and drying to powder and obtaining desired photocatalyst.