Atomically Dispersed Zr-N Moieties Modulate Fe Coordination for Robust Oxygen Reduction Electrocatalysis

Iron-nitrogen-carbon (Fe-N-C) materials are promising non-precious metal catalysts for the oxygen reduction reaction (ORR), yet their long-term stability remains a critical challenge due to the dissolution of Fe-based active sites and corrosion of the carbon support. Here, a Fe-Zr dual-atom carbon-based catalyst (Fe,Zr-NC) via a one-step solid-state synthesis method is reported. The introduction of atomically dispersed Zr-N units adjacent to Fe-N₄ centers creates a dual-metal coordination structure that modulates the local electronic environment of Fe and weakens ^*OH adsorption, which is the rate-limiting step in the ORR process. Density functional theory (DFT) calculations reveal that the Fe-Zr synergy positions the catalyst near the apex of the ORR activity volcano. Extended experimental EXAFS confirms a Fe-Zr distance of ≈3.30 Å, closely matching the theoretical optimum (≈3.39 Å). As a result, Fe, Zr-NC achieves a high half-wave potential (0.891 V vs reversible hydrogen electrode (RHE)) with negligible activity loss over 5000 cyclic voltammetry cycles, outperforming commercial Pt/C. In zinc-air batteries, the catalyst delivers a peak power density of 185.7 mW cm^-2 and operates stably for over 453 h. This work highlights the importance of dual-atom synergy in tuning intermediate binding energies and provides design principles for next-generation ORR electrocatalysts.