Identifying the imposter in inks of highly active Pt-alloyed catalysts for hydrogen PEMFCs

One of the main bottlenecks of proton exchange membrane fuel cells (PEMFC) technology is the inefficient catalyst for cathodic oxygen reduction reaction, limiting their efficiency. Pt-alloyed catalysts, either shaped-controlled octahedra oh-PtNiIr or PtCo intermetallics, exhibit significantly increased activity than commercial Pt nanoparticles but only in laboratory measurements. The ink nature is expected to play a critical role in PEMFC devices, as the catalyst layer manufactured from the ink has to ensure good proton and electron conductivity to the active sites on the catalyst surface, which is difficult in the case of highly active catalysts. Here we propose a study allowing an understanding of the catalyst-support-ionomer interface formation. We plan to perform an in-situ X-ray Diffraction experiment enabling reconstruction of the catalyst local environment from the angstrom to the nanometre scale at each step of the ink and catalyst layer manufacturing.