Facile synthesis of magnetic ZnFe sub(2)O sub(4)-reduce d graphene oxide hybrid and its photo-Fenton-like behavior under visible iradiation

A magnetic ZnFe sub(2)O sub(4)-reduce d graphene oxide (rGO) hybrid was successfully developed as a heterogeneous catalyst for photo-Fenton-like decolorization of various dyes using peroxymonosulfate (PMS) as an oxidant under visible light irradiation. Through an in situ chemical deposition and reduction, ZnFe sub(2)O sub(4) nanoparticles (NPs) with an average size of 23.7 nm were anchored uniformly on rGO sheets to form a ZnFe sub(2)O sub(4)-rGO hybrid. The catalytic activities in oxidative decomposition of organic dyes were evaluated. The reaction kinetics, effect of ion species and strength, catalytic stability, degradation mechanism, as well as the roles of ZnFe sub(2)O sub(4) and graphene were also studied. ZnFe sub(2)O sub(4)-rGO showed to be a promising photocatalyst with magnetism for the oxidative degradation of aqueous organic pollutants and simple separation. The combination of ZnFe sub(2)O sub(4) NPs with graphene sheets leads to a much higher catalytic activity than pure ZnFe sub(2)O sub(4). Graphene acted as not only a support and stabilizer for ZnFe sub(2)O sub(4) to prevent them from aggregation, largely improving the charge separation in the hybrid material, but also a catalyst for activating PMS to produce sulfate radicals at the same time. The ZnFe sub(2)O sub(4)-rGO hybrid exhibited stable performance without losing activity after five successive runs.