A novel electrosorption enhanced electro-Fenton (ES-EF) method for wastewater treatment was proposed. Mixed-valence iron oxide grown on bulk activated carbon aerogel (FeOx/ACA) was successfully developed as a bifunctional integrated cathode for ES-EF process to purify wastewater. The FeOx/ACA, was prepared firstly by activating carbon aerogel substrate to develop surface area and then controlling Fe(III) reduction to forming the mixed-crystal of Fe2O3 and Fe3O4. The FeOx/ACA was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), N-2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) techniques. When the composite cathode was applied in an ES-EF system at neutral pH for removing high concentration imidacloprid (237 mg L-1), 93% TOC removal was achieved in 150 min and the energy consumption removal per unit TOC was only 31% of that in the traditional electro-Fenton with graphite cathode. Results showed that the FeOx/ACA was not only a good electro-Fenton catalyst but also an excellent electrosorption electrode due to its high specific surface area. The electrosorptive ability promoted pollutants mass transfer and H2O2 electrogeneration. The mechanism of synergistic ES-EF degradation was also proposed. Furthermore, it is noteworthy that FeOx/ACA was quite stable and it could be reused without obvious decrease in catalytic activity within 900 min, suggesting its potential application for wastewater treatment. (C) 2013 Elsevier B.V. All rights reserved.