Synergistic spin-state and local coordination engineering offers a promising strategy for enhancing the acidic oxygen reduction reaction performance of Fe–N–C electrocatalysts, yet the precise control and stabilization of active sites remain challenging. Here we report a Fe–La geminal-atom electrocatalyst (Fe1-La1/NC) with spontaneous ferromagnetic spin ordering for acidic oxygen reduction reaction. The catalyst achieves a half-wave potential of 0.92 V and a turnover frequency of 17.3e-site−1s−1, compared with commercial Pt/C (0.87 V, 9.9e-site−1s−1). A proton exchange membrane fuel cell equipped with Fe1-La1/NC cathode delivers a high current density of 56 mA cm−2 at 0.9ViR-free under H2-O2 condition, while maintaining stable operation for 100 h at 0.67 V with 86% performance retention. Operando studies and theoretical simulations reveal that La incorporation promotes a spin-polarized high-spin Fe 3 d configuration and room-temperature ferromagnetic ordering, while also regulating the local coordination/electronic structure and oxygen-intermediate adsorption. Moreover, La enables dynamic self-adaptive stabilization of Fe sites, which mitigates the conventional activity–stability trade-off. This finding provides an avenue to rationally design efficient and selective electrocatalysts.

Nature Communications, 2026, 17, 11592 https://doi.org/10.1038/s41467-026-77285-7