The investigation of resin degradation in catalyst layer of proton exchange membrane fuel cell

•A simple method is provided to isolate the membrane degradation in situ.•The resin degradation of catalyst layer is specially discussed.•The prominent degradation location at open circuit operation is discussed.

In order to separate resin degradation in catalyst layer (CL) from membrane degradation of proton exchange membrane fuel cell (PEMFC), Fluorine emission rate (FER) was specially selected to highlight the degradation of Nafion® resin in CL by employing hydrocarbon membrane as membrane. The drain water from the cathode and anode was collected and analyzed separately. It is found that FERs of drain water are 0.065 μmol cm−2 h−1 (cathode) and 0.049 μmol cm−2 h−1 (anode), suggesting resin degradation happened in CLs and the predominant degradation occurred in the cathode in open circuit operation.