BUFFER LAYER AND METHOD FOR MITIGATION OF PHOSPHATE POISONING IN HIGH-TEMPERATURE PROTON EXCHANGE MEMBRANE FUEL CELLS (HT-PEMFC)

The present disclosure relates to high-temperature proton exchange membrane fuel cells (HT-PEMFC) having phosphoric acid as a proton conductor, and methods for mitigating phosphate poisoning of the catalyst in the fuel cell. The fuel cells and the method include a buffer layer between metal catalyst nanoparticles and at least one polymeric ionomer layer. The buffer layer includes a protic ionic liquid having a high melting point greater than 160° C., and the ratio of the protic ionic liquid to carbon (IL/C) is from about 0.1 to about 0.2.