Time-resolved monitoring of composite Nafion™ XL membrane degradation induced by Fenton's reaction

Although proton-exchange membrane fuel cells (PEMFC) are considered as a safe and clean energy technology, aging phenomena of the membrane-electrode assembly (MEA), and more particularly of the membrane, still restrict PEMFC lifetime. In this paper, ex-situ accelerated chemical degradation – via Fenton's reagents exposure – of reinforced Nafion™ XL membrane is performed in order to investigate the impact of chemical degradation on membrane structure and properties in comparison with unreinforced Nafion™ NR211 membrane. Results demonstrated that both XL and NR211 membranes undergo chemical decomposition after exposure to Fenton's reagents at different degradation rate. Emissions of two main degradation products released by the Nafion™ membranes were monitored as a function of exposure time, demonstrating the greater stability of the XL membrane compared to the NR211 membrane. However, the impact of chemical degradation on water sorption and water transport properties seems negligible for both membranes. This study aims at providing new insight on chemical degradation of composite Nafion™ XL membrane.