Advances in Atomic Iron Catalysts for Oxygen Electrocatalysis

Abstract The severe environmental issues triggered by the overuse of fossil energy have propelled the development of energy conversion and storage technologies. Oxygen electrocatalysis, including oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), has attracted widespread attention as the key reaction of many energy devices. Increasing research has demonstrated the exceptional potential of atomic iron catalysts in oxygen electrocatalysis, offering promising prospects for advancing these technologies. Building upon an analysis of the mechanisms underlying oxygen electrocatalysis and integrating insights from characterization techniques and theoretical calculations, this paper systematically summarizes the strategies for regulating the electronic structure of atomic iron catalysts, including coordination environment, metal active center, and substrate modulation. Then, given that the stability of Fe–N–C catalysts remains a fundamental bottleneck hindering their development, optimization strategies including adjusting the Fe─N bond length, reducing H ₂ O ₂ attack, and improving the graphitization degree of the carrier are proposed. Furthermore, the applications in energy storage and conversion devices are reviewed. Finally, the future challenges and opportunities for atomic iron catalysts are discussed, offering insights for the development of more advanced Fe‐based catalysts.