Impact of catalyst layer morphology on the operation of high temperature PEM fuel cells

Electrochemical impedance spectroscopy (EIS) is a well-established method to analyze polymer electrolyte membrane fuel cell (PEMFC). However, without further data processing, the spectrum yields only qualitative insight into mechanism and individual contribution of transport, kinetics, ohmic losses overall limitations. The distribution relaxation times (DRT) allows quantifying each these polarization evaluates their given electrocatalyst's depreciated performances. We coupled this with detailed morphology study investigate impact 3D-structure on processes occurring inside high-temperature (HT-PEMFC). tested platinum catalyst (Pt/C), platinum-cobalt alloy (Pt3Co/C), group metal-free iron-nitrogen-carbon (Fe–N–C) catalyst. found that hampered mass transport in latter mainly responsible for its low performance MEA (along decreased intrinsic performances ORR reaction). better can be explained by both improved lower resistance. Furthermore, single-cell tests show layer influences phosphoric acid during conditioning.