Double Passivation Water Based Galvanic Displacement Method for Reproducible Gram Scale Production of High Performance Pt‐alloy Electrocatalysts

: Preparation of large quantities of high-performance supported Pt-alloy electrocatalysts is crucial for the faster development and implementation of low-temperature proton exchange membrane fuel cells (PEMFCs). One of the prospective nanofabrication synthesis methods is based on the galvanic displacement (GD) reaction. A facile, highly reproducible, gram scale, water-based double passivation GD method is now presented for the synthesis of carbon-supported Pt-M nanoparticles (M=Cu, Ni, Co). It offers great flexibility over the catalyst design, such as the choice of the sacrificial metal (M), variation of the chemical composition of alloy, variation of total metal loading (Pt+M) on carbon support, or even variation of the carbon support itself. The obtained Pt-alloy catalysts are several times more active compared to a Pt reference and exhibits better stability during accelerated degradation tests performed at 60 °C.