Multigram-Scale Synthesis of High-Pt-Content PtCo Intermetallic Catalysts for Proton Exchange Membrane Fuel Cells

Carbon-supported PtCo intermetallic nanoparticles rank as one of the most efficient cathode catalysts for proton exchange membrane fuel cells (PEMFCs). Nevertheless, developing simple and scalable synthetic approaches for effective size control of this type of catalyst at high Pt contents continues to be a significant challenge. Herein, we introduce a sulfur-containing molecule-assisted ball-milling method, enabling the multigram-scale synthesis of PtCo intermetallic catalysts with a high Pt content of 48 wt %. This method results in a fine dispersion of PtCo intermetallic nanoparticles on carbon black supports with an average particle size of 5.29 nm. The resulting catalyst demonstrates remarkable performance in H2-Air PEMFC tests, exemplified by a power density of 1.16 W/cm2 at 0.7 V and maintaining 65% of its mass activity after an accelerated durability test.