A nonelectrochemical reductive deposition of ruthenium adatoms onto nanoparticle platinum: anode catalysts for a series of direct methanol fuel cells

The surface of Pt nanoparticles was cleaned and saturated with hydrogen by treatment first with a 3% aqueous solution of H2O2 and then with hydrogen gas under water at room temperature. Reaction between the surface hydrogen and aqueous RuCl3 deposited 0.18 surface equivalents of RUad onto the Pt nanoparticles. The deposition was repeated several times, with each reaction depositing similar to0.18 surface equivalents more Ru-ad onto the Pt-Ru-ad nanoparticles. The resulting Pt-Ru-ad nanoparticles were analysed using cyclic voltammetry, CO stripping voltarnmetry, and as catalysts for electrooxidation of MeOH in three-electrode experiments and in prototype direct methanol fuel cells. The optimum surface coverage (0(Ru)) for electrooxidation of MeOH was similar to0.33 under these conditions. (C) 2003 Elsevier Ltd. All rights reserved.