▎ 摘　　要

NOVELTY - Preparing graphene complex magnetic photocatalyst manganese-zinc ferrites/bismuth vanadate/reduced graphene oxide comprises e.g. preparing solution A, B and C, adding solution B to C, adding solution A to B and C mixed solution, preparing bismuth vanadate precursor solution, drying, removing grinded solid, to obtain magnetic manganese-zinc ferrites/bismuth vanadate complex, preparing spherical bismuth vanadate monoclinic crystal particles and graphene oxide solution, adding e.g. manganese-zinc ferrites/bismuth vanadate, filtering, washing and drying. USE - The complex catalyst is useful for photocatalytic degradation of rhodamine B (claimed). ADVANTAGE - The magnetic complex has high visible light catalytic activity; strong conductive ability; is easy to recycle; and has high stability (claimed). The complex catalyst has a degradation rate of 96%; specific saturated magnetization intensity of 8.21 emu.g-1; applies strong magnetic field to facilitate the use of recovery with a recovery rate of not less than 89%; and can improve removal efficiency and speed by using the organic pollutants in the light degradation. DETAILED DESCRIPTION - Preparing graphene complex magnetic photocatalyst manganese-zinc ferrites/bismuth vanadate/reduced graphene oxide comprises (a) preparing bismuth vanadate precursor solution comprising dissolving analytically pure bismuth(III) nitrate pentahydrate in 2 mol/l nitric acid, ultrasonically oscillating, to obtain solution A, where molar ratio of bismuth(III) nitrate pentahydrate and tartaric acid is 10:2-4, dissolving analytically pure tartaric acid in hot water at 80 degrees C, to obtain solution B, where the molar ratio of bismuth(III) nitrate pentahydratea and ammonium metavanadate is 1:1, dissolving analytically pure ammonium metavanadate in hot water at 80 degrees C, to obtain solution C, slowly adding solution B to the solution C, adding solution A to the mixed solution of B and C, cooling, adjusting pH to 7.5 with aqueous ammonia solution, to obtain bismuth vanadate precursor solution, (b) taking manganese-zinc ferrites and bismuth vanadate in a mass ratio of 15:100, adding the laboratory-made magnetic manganese-zinc ferrites, to obtain bismuth vanadate precursor solution, stirring at 80 degrees C under water bath condition for 0.5 hour, drying the reacting solution at 80 degrees C for 24 hours, removing the grinded solid, baking in a muffle furnace at 450 degrees C for 3 hours, to obtain magnetic manganese-zinc ferrites/bismuth vanadate complex, preparing spherical bismuth vanadate monoclinic crystal particles in a same manner having a particle diameter of 2-5 mu m without adding manganese-zinc ferrites, (c) preparing graphene complex magnetic photocatalyst manganese-zinc ferrites/bismuth vanadate/reduced graphene oxide with potassium permanganate oxide graphene powder, to obtain graphene oxide (GO), where the mass ratio of manganese-zinc ferrites/bismuth vanadate/graphene oxide is 100:1-5, ultrasonically dispersing graphene oxide in deionized water, to obtain graphene oxide solution, adding graphene oxide in the preparation of manganese-zinc ferrites/bismuth vanadate, where the volume-mass ratio of ammonium hydroxide solution and graphene oxide is 1:24-36 and the volume ratio of ammonium hydroxide solution and hydrazine hydrate solution is 1:1-3, adding ammonium hydroxide solution and hydrazine hydrate solution, reacting in a water bath at 80 degrees C such that graphene oxide is reduced to graphene (RGO), filtering, washing, drying for 12 hours.