The purpose of this study is to develop a novel binary Iridium-Cobalt/C catalyst as a suitable substitute for platinum/C applied in proton exchange membrane fuel cells (PEMFCs). The carbon-supported IrCo catalysts were successfully synthesized using IrCl3 and C4H6CoO4 as the Ir and Co precursors respectively, in ethylene glycol (EG) refluxing at 120 degrees C. The nanostructured catalysts were characterized by X-ray diffraction (XRD) and high-resolution transmission electron microscope (TEM). Homogeneous catalyst particles supported on carbon showed a size of proximately 2 nm. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) were conducted for the characterization of the catalyst performances. With a cathodic loading of 0.4 mg(lr). cm(-2), 20%Ir-30%Co/C achieved a maximum power density of 501.6 mW cm(-2) at 0.418 V, with a 50 cm(2) H-2/O-2 single cell. Although such a performance is about 26% lower than commercial Pt/C catalyst, it is still helpful in terms of Pt replacement and cost reduction. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.