Gong, QingZhang, HongYu, HaoranJeon, SunghuRen, YangYang, ZhenzhenSun, Cheng-JunStach, Eric A.Foucher, Alexandre C.Yu, YikangSmart, MatthewFilippelli, Gabriel M.Cullen, David A.Liu, PingXie, Jian2024-12-172024-12-172023-03Gong, Q., Zhang, H., Yu, H., Jeon, S., Ren, Y., Yang, Z., Sun, C.-J., Stach, E. A., Foucher, A. C., Yu, Y., Smart, M., Filippelli, G. M., Cullen, D. A., Liu, P., & Xie, J. (2023). Amino-tethering synthesis strategy toward highly accessible sub-3-nm L10-PtM catalysts for high-power fuel cells. Matter, 6(3), 963–982. https://doi.org/10.1016/j.matt.2022.12.011https://hdl.handle.net/1805/45104Because of the poor accessibility of embedded active sites, platinum (Pt)-based electrocatalysts suffer from insufficient Pt utilization and mass transport in membrane electrode assemblies (MEAs), limiting their performance in polymer electrolyte membrane fuel cells. Here, we report a simple and universal approach to depositing sub-3-nm L10-PtM nanoparticles over external surfaces of carbon supports through pore-tailored amino (NH2)-modification, which enables not only excellent activity for the oxygen reduction reaction, but also enhanced Pt utilization and mass transport in MEAs. Using a low loading of 0.10 mgPt·cm−2, the MEA of PtCo/KB-NH2 delivered an excellent mass activity of 0.691 A·mgPt−1, a record-high power density of 0.96 W·cm−2 at 0.67 V, and only a 30-mV drop at 0.80 A·cm−2 after 30,000 voltage cycles, which meets nearly all targets set by the Department of Energy. This work provides an efficient strategy for designing advanced Pt-based electrocatalysts and realizing high-power fuel cells.enPublisher Policyplatinum-based intermetallicL10-PtCo nanoparticleamino modificationArticle