Unravelling the degradation mechanism of intermetallic Pt3V catalyst for heavy-duty PEMFC cathode via operando WAXS

Intermetallic (ordered) PtM bimetallic nanoparticles (e.g. M = Co, Ni) have been shown to possess a high performance for the oxygen reduction reaction (ORR) compared to disordered catalysts. However, their moderate durability is still a grand obstacle against their commercialization into proton exchange membrane fuel cells (PEMFCs) due to significant leaching of less acid-resistant metals under the corrosive conditions. We developed an intermetallic L12-Pt3V catalyst with a novel synthetic strategy with Zn as dopant showing enhanced ordering degree and ORR performance. There is a lack of plausible information to explain the enhanced durability and lattice compression changing during accelerated stress test (AST). Therefore, we would like to perform an operando wide-angle X-ray scattering (WAXS) measurement on our Pt3V and Pt3V(Zn) catalysts to unravel their degradation mechanism such as lattice parameter and ordering degree changings during AST under realistic conditions of fuel cell.