Methanol electrooxidation on platinum/ruthenium nanoparticle catalysts

Using the spontaneous deposition method (W Chrzanowski and A. Wieckowski, L angmuir 13, 5974 (1997)), platinum nanoparticles were decorated with ruthen ium to obtain a Pt/Ru catalyst with a packing density of up to 0.65 Ru atom s per Pt surface atom. The activity of this catalyst toward methanol electr ooxidation was tested at electrode potentials of interest for fuel cells. T he catalyst activity maximizes at ruthenium packing density 0.4-0.5, and th e catalyst is twice as active (displays higher current densities normalized to real surface area) as the commercial 50: 50 Pt/Ru alloy catalyst. Hydro gen adsorption on the decorated Pt/Ru and Pt/Ru alloy surfaces is also repo rted. (C) 2001 Academic Press.