The electrochemical reduction of oxygen at poly(o-phenylenediamine) (PoPD) modified platinum electrode was studied. Platinum particles with a diameter of about 100 nm were electrodeposited onto the polymer matrix. The platinum loading was varied from 3.9 to 175 mu g/cm(2). Experiments have also been carried out on unmodified platinum electrode and platinum particles deposited platinum electrodes for direct comparison. The films were characterized by AM Rotating disc electrode experimental data indicated a one step four electron reduction. It is demonstrated that nearly a seventyfold increase in the oxygen reduction current can be obtained on the platinum incorporated PoPD electrode compared to the bulk platinum electrode. (c) 2006 Elsevier B.V. All rights reserved.