Ceramic supported Pt and Pt-Ru catalysts for methanol oxidation

摘要

Pt and Pt-Ru are the primary catalysts used for electrodes in direct methanol fuel cells (DMFCs). Noble metals are expensive, and present a significant cost barrier to commercially viable fuel cells. Dispersing these catalysts onto support materials has effectively reduced the noble metal loading required for fuel cell electrodes and reduced fuel cell costs. High surface area carbon has been the most popular fuel cell catalyst support material. While relatively stable, carbon serves only to disperse the noble metal catalysts. No catalytic activity is displayed by the carbon support material, either directly or indirectly, toward methanol oxidation. Additionally, the density of carbon is low, hence a large volume of supported catalyst is required for higher Pt loadings needed for high power density DMFCs. Large volumes of supported catalysts impose detrimental mass transport effects on fuel cell performance through necessarily thick catalyst layers and limit DMFC power densities (1.2).