Although proton exchange membrane fuel cells (PEMFCs) are emerging as an efficient and green technology, their heavy reliance on scarce and exorbitant price platinum catalysts for the oxygen reduction reaction (ORR) hampers large-scale commercialization 1 . The strain effect, induced through the alloying of Pt with transition metals, can enhance the catalytic activity as well as reduce the platinum loading 2 . While this has been well documented, these catalysts’ durability has received limited attention 3 . In this work, we report a new class of PtMn alloy catalysts with low-electronegativity Mn-contraction which boosts the oxygen reduction durability of fuel cells. X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) reveal that the PtMn catalyst with moderate strain shows the best activity (0.53 A mg -1 at 0.9 V RHE). The PtMn alloy catalyst achieves an outstanding mass activity retention of 96% after 10,000 degradation cycles in liquid electrolyte due to the low-electronegativity of Mn, with far superior performance than highly electronegative PtNi alloys. Finally, the PtMn catalyst in PEMFC achieves an outstanding peak power density of 1.4 W cm -2 using half the loading of commercial Pt/C, and good stability over 50 h at 0.6 V in H 2 -O 2 . Figure 1
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Nie et al. (2024) studied this question.