In situ durability of various carbon supports against carbon corrosion during fuel starvation in a PEM fuel cell cathode.

In this study, the degradation of different cathode carbon supports is investigated in proton exchange membrane fuel cells (PEMFCs). A platinum catalyst is synthesized using various carbon supports, such as Vulcan XC-72, graphite nanopowder and carbon nanotube, which are evaluated based on the fabrication of membrane electrode assemblies. During the startup and shutdown of PEMFCs, the individual electrode potential can be measured in situ using a dynamic hydrogen electrode. The cathode potential increases instantaneously to 1.4 V in one attempt, when H2/air boundaries are developed on the anode side during the fuel starvation, leading to significant carbon corrosion. The corrosion rates of various carbon supports are calculated from the concentration of gases, such as CO2, CO and SO2, emitted from the cathode outlet, measured directly in situ by Fourier transform infrared gas analysis. The carbon nanotube-supported Pt catalyst shows the best performance against carbon corrosion during fuel starvation, compared to commercial Pt/C catalyst and other types of carbon supports.