Durability of Pt Catalysts Supported on Ordered Mesoporous Carbon for Proton Exchange Membrane Fuel Cells

Abstract

Ordered mesoporous carbons (OMCs) are investigated as support materials of Pt catalyst in proton exchange membrane fuel cells. Four types of Pt/OMC catalysts are prepared and their electrochemical performances and durability are evaluated by cyclic voltammetry and linear sweep voltammetry using a rotating disk electrode system. Pt nanoparticles of 2-3 nm seem to be uniformly dispersed on the supports regardless of the kind of OMC. The different pore structure between CMK-3 and CMK-5 affects the surface areas of carbon supports and the resulting Pt nanoparticles with indicating that larger surface area accompanies higher oxygen reduction reaction (ORR) activity. Although the graphitization of carbon support from CMK-3 to CMK-3G reduces the surface area of carbon support, the surface area and the ORR activity of Pt nanoparticles on CMK-3G are increased. In general, the reductions in electrochemical surface area (ECSA) and ORR activity become more noticeable in proportion to the initial ECSA and ORR of Pt/OMC after accelerated durability test.