Effect of Surface Composition of Platinum-ruthenium Nanoparticles on Methanol Oxidation Activity

摘要

Direct methanol fuel cells (DMFCs) are a very promising power source owing to their high energy density and portability (1). In the case of a DMFC, the anode over potential needed for oxidizing the methanol solution is considerably large. To increase the power density of a DMFC, it is therefore important to improve the catalytic activity of the anode. In the anode of a DMFC, platinum-ruthenium nanoparticles on carbon supports are generally used as a catalyst because of their higher methanol oxidation activity relative to platinum nanoparticles (2-4). It is known that the higher activity of a platinum-ruthenium catalyst is due to the following bi-functional mechanism (4).