A simple and efficient electrochemical oxidation method was used to modify the graphite felts. A remarkable change on the surface chemistry was observed by the X-ray photoelectron spectrum analysis. The modified electrodes were found having much higher electrocatalytic activity toward oxygen reduction reaction than the pristine one, and thus, the in situ production of H2O2 and the enhanced decontamination efficiency in Electro-Fenton (EF) system. The accumulation of H2O2 at the optimal modified electrode was as about 2.7 times as the pristine one. After optimizing the operational parameters such as Fe3+ concentration, potentials, pH and O-2 flow rate, the mineralization of p-nitrophenol could be above 78%. It can be expected to perform the EF system under these optimal conditions to improve treatment efficiency. (C) 2013 Elsevier B.V. All rights reserved.