Carbon supported Ir nanoparticles modified and dealloyed with M (M = V, Co, Ni and Ti) as anode catalysts for polymer electrolyte fuel cells

Very active carbon-supported Ir modified with transition metal M catalysts (M = V, Co, Ni and Ti) were synthesized by an ethylene glycol (EG) reduction method as novel, suitable anode electrode materials for polymer electrolyte membrane fuel cells (PEMFCs) applications. IrM nanoparticles showed a narrow particle size distribution centered around 2-3 nm, and were uniformly dispersed on Vulcan XC-72 supports. Investigation of the catalytic activity by means of linear sweep voltammetry (LSV) employing a rotating disk electrode (RDE) setup has revealed that the activities of these catalysts follows the order of IrCo/C > IrV/C > IrNi/C > IrTi/C > commercial Pt/C > Ir/C toward the hydrogen oxidation reaction (HOR). Membrane electrode assemblies (MEA) prepared with the IrM/C anode catalysts demonstrated the beneficial impact of transition metal addition during catalyst synthesis, with IrCo/C and IrV/C providing the highest MEA power densities. EDX results indicated that these two catalysts contained negligible Co and V contents, respectively, indicating a beneficial dealloying effect resulting from HCl addition during catalyst synthesis. Herein, IrM/C materials are presented as promising replacements to conventional platinum based materials for utilization as anode electrocatalysts for PEMFC applications. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.