Abstract: A proton exchange membrane fuel cell includes at least one membrane-electrode assembly including an electrolyte membrane based on a fluorine free polymer grafted with side chains containing proton conductive functional groups, and interposed between an anode and a cathode, the anode including a catalytic layer including a catalyst and a fluorinated ionomer. The catalytic layer has a fluorine/catalyst ratio that increases in a direction from the electrolyte membrane to an outer surface of the anode.