Résumé
Improvement of catalytic activity and durability are key steps towards a widespread commercialization of proton exchange membrane fuel cells. These are highly dependent on the surface structure of the nanocatalysts. Using Bragg Coherent Diffraction Imaging (BCDI), a state-of-the-art single crystal X-ray characterization technique, we aim at reconstructing the 3D strain fields of Pt nanoparticles (NP) under electrochemical control (in situ). Based on a novel sample preparation technique, we are confident that we will be able to assess the full range of structural changes occurring on the surface of the catalyst in the presence of oxygenated intermediates (oxygen reduction reaction and degradation processes such as place exchange mechanism) and to provide a holistic understanding of the surface strain evolution on the nanoscale during the real-world operation of fuel cells.