Hydrous ruthenium oxides have been investigated as novel
support materials for fuel cell electrocatalysts for use in
DMFC applications. These oxides were chosen in particular
due to their potential intrinsic proton conductivity. Pt nanoparticles have been deposited onto the new support, and the resulting catalysts characterized both structurally and electrochemically. The Pt nanoparticles are sized between
3–4 nm and are highly dispersed on the support. Transmission
electron micrographs show that the individual Pt nanoparticles are covered by an amorphous coating layer – probably hydrous ruthenium oxide, in good agreement with the
XPS data. Electrochemical measurements on model electrodes
indicate that proton conductivity of the supporting
material is strongly affected by interdiffusion of methanol.
Nevertheless, initial tests on membrane electrode assemblies
(MEAs) showed improved performance, particularly with
respect to internal resistance, when compared to Pt-Ru
black. The catalyst showed very high activity in CO stripping experiments performed on a full MEA, suggesting high catalyst utilization, despite the comparatively low Nafion® content used in the electrode layer
