Novel methanol-tolerant Ir-S/C chalcogenide electrocatalysts for oxygen reduction in DMFC fuel cell

Novel methanol-tolerant oxygen-reduction catalysts, iridium-sulphur (Ir-S) chalcogenides with different Ir/S atomic ratios, were synthesized via a precipitation method using H(2)IrCl(6) and Na(2)SO(3) as the Ir and S precursors. Powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the Ir(x)S(1-x)/C chalcogenide catalysts. Particle size ranging from 2.5 to 2.8 nm though obvious agglomeration was found on carbon support. However, these chalcogenide catalysts showed strong catalytic activity towards the oxygen reduction reaction (ORR) and high methanol tolerance, strongly suggesting these novel catalysts as promising candidates for direct methanol fuel cell (DMFC) cathode applications. (C) 2011 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.