▎ 摘　　要

Based on the peroxidase-like activity of hemin and unique physicochemical property of graphene, a novel electroenzymatic system was developed for degradation of diclofenac. The graphene-hemin hybrid materials were prepared and characterized by Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), which were then immobilized on the graphite electrode surface and studied by electrochemical impedance spectroscopy (EIS). In the electroenzymatic process, hydrogen peroxide (H2O2) was generated from the electroreduction of oxygen through aeration to the electrolytic solution, which could oxidize and degrade organic compounds under the catalysis of hemin. Graphene was found to effectively promote the removal efficiency of such an electroenzymatic process. Using the graphene-hemin integrated electroenzymatic system, more than 96% of diclofenac could be removed after 11-h treatment. According to liquid chromatography-mass spectrometric (LC-MS) analysis, the mechanism for electroenzymatic degradation of diclofenac was proposed. This study demonstrated a novel degradation method for control of emerging pollutants. (C) 2015 Elsevier Ltd. All rights reserved.