High Catalytic Activity in the Phenol Hydroxylation of Magnetically Separable CuFe2O4–Reduced Graphene Oxide

We reported a highly active CuFe2O4 catalyst modified with reduced graphene oxide (CuFe2O4–RGO) by a solvothermal method. The composite catalyst was fully characterized by FTIR, XRD, Raman, TEM, and XPS, which demonstrated that the CuFe2O4 nanoparticles (NPs) with a diameter of approximately 17.8 nm were densely and compactly deposited on the reduced graphene oxide (RGO) sheets. The as-prepared CuFe2O4–RGO composites were used to catalyze phenol hydroxylation for the first time, which exhibited great catalytic activity. The conversion rate of phenol to dihydroxybenzenes reached 35.5% with a selectivity of 95.2% obtained, which is much higher than for reported systems (25.0%). The catalytic activity remained high after six cycles. More importantly, the catalyst can be easily recovered due to its magnetic separability and the organic solvent-free nature of the phenol hydroxylation process. A possible mechanism in phenol hydroxylation by H2O2 over CuFe2O4–RGO20 catalyst was also proposed.

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