Multi-atom Pt and PtRu catalysts for high performance AEMFCs with ultra-low PGM content

To reduce the platinum group metal (PGM) loading in anion exchange membrane fuel cells (AEMFCs), it is important to transition to catalysts with very low PGM content, and eventually to catalysts that are completely PGM-free. In this work, four supported low-PGM Pt and PtRu catalysts were prepared using a new, simple, scalable technique: Controlled Surface Tension (CST) method. CST allows for a high density of very small multi atom clusters. Catalysts were physically characterized using a wide array of techniques and tested for their ORR and HOR activity both ex-situ and integrated into operating AEMFCs. The PGM loading was reduced by a factor of 14 while achieving comparable performance to commercial catalysts. AEMFCs were also assembled with ultralow PGM loading (0.05 mg(PGM) cm(-2)), where PtRu anodes were paired with Fe-N-C cathodes to achieve a specific power of 25 W/mg(PGM) (40 W/mg(Pt)).

Automated summary

To reduce PGM loading in AEMFCs, low-PGM Pt and PtRu catalysts were prepared using a new CST method, which allows for a high density of small multi atom clusters. The catalysts were characterized and tested for their activity both ex-situ and in operating AEMFCs. The PGM loading was reduced by 14 times while achieving comparable performance to commercial catalysts. AEMFCs with ultralow PGM loading (0.05 mg(PGM) cm(-2)) achieved a specific power of 25 W/mg(PGM) (40 W/mg(Pt)) by using PtRu anodes paired with Fe-N-C cathodes.