Synthesis of porous carbons having surface functional groups and their application to direct-methanol fuel cells

Abstract

Pitch-based porous carbons having –SO 3H groups on their surfaces were synthesized by carbonization of mesophase pitch and then sulfonation of the resulting compounds. As-synthesized carbons were characterized by BET surface area analysis, pore volume analysis and XRD. The concentration of –SO 3H groups present on the carbons was measured by neutralization titration. PtRu nano-clusters were supported on the pitch-based porous carbons, and these electrocatalysts were used as anodic materials in a DMFC. Membrane–electrode assemblies prepared using these electrode materials showed an improved power density compared with a commercial 60% PtRu/Vulcan XC-72. This performance is ascribed to the higher ionic conductivity of the anode layer and the well exposed catalytic active sites.