Synthesis of small-sized intermetallic PtCo fuel cell catalysts by promoting inner surface utilization of carbon supports

Carbon-supported PtCo intermetallic nanoparticles are competitive low-platinum cathodic oxygen reduction reaction (ORR) catalysts for proton exchange membrane fuel cells (PEMFCs), but their synthesis needs high-temperature annealing that causes the catalyst to severely sinter. Here, we contrastively investigate the wet-impregnation and oleylamine-mediated colloid methods for the syntheses of PtCo intermetallic catalysts on various high-surface-area carbon supports with different porous structures. We identify that the efficient utilization of the internal surface area of porous carbon supports is crucial for the synthesis of small-sized PtCo intermetallic catalysts, which is highly dependent on the metal deposition method as well as the pore structure of the carbon supports. Accordingly, small-sized PtCo intermetallic catalysts with enhanced ORR activity and promoted PEMFC performance were prepared by the wet-impregnation method on mesoporous carbon supports.

Automated summary

We investigated the effects of wet-impregnation and oleylamine-mediated colloid methods on the synthesis of PtCo intermetallic catalysts on different porous carbon supports. It was found that efficient utilization of the internal surface area of porous carbon supports is crucial for the synthesis of small-sized PtCo intermetallic catalysts, which is highly dependent on the metal deposition method and the pore structure of the carbon supports. As a result, small-sized PtCo intermetallic catalysts with enhanced oxygen reduction reaction activity and improved proton exchange membrane fuel cell performance were prepared using the wet-impregnation method on mesoporous carbon supports.