Xue Zhang, Hao Sun, Yuanhua Sun, Xiaokang Liu, Zhaochun Cao, Wei Zhang, Linlin Cao, Tao Yao
Consequently, the catalyst demonstrates exceptional oxygen reduction reaction (ORR) activity with a half-wave potential of 0.921 V, a mass activity (MA) of 0.96 A mg Pt –1 and a negligible half-wave potential shift after 30 000 cycles.
Developing active and durable platinum-based catalysts is critical for advancing proton-exchange membrane fuel cells (PEMFCs). To overcome the Cu dissolution and poor stability of PtCu intermetallics, we propose a Mn-doping strategy to fabricate L1 0 -ordered PtCuMn nanocatalysts. Mn incorporation modulates the Pt electronic structure, enhances L1 0 ordering, and induces compressive strain within a Pt-rich shell. Consequently, the catalyst demonstrates exceptional oxygen reduction reaction (ORR) activity with a half-wave potential of 0.921 V, a mass activity (MA) of 0.96 A mg Pt –1 and a negligible half-wave potential shift after 30 000 cycles. In PEMFCs, it delivers peak power densities of 1.31 W cm –2 (H 2 –air) and 2.23 W cm –2 (H 2 –O 2 ). Furthermore, its MA reaches 0.78 A mg Pt –1, which exceeds the U.S. Department of Energy (DOE) 2025 target. Operando characterizations and theoretical calculations confirm that Mn doping downshifts the Pt d-band center, accelerates the conversion kinetics of the key *OH intermediate, and thereby optimizes the ORR performance.