Electronic structure regulation of the Fe-based single-atom catalysts for oxygen electrocatalysis

The excessive consumption of fossil energy causes serious environmental problems, which has driven the exploration of clean and sustainable energy. Oxygen electrocatalysis as the core reaction of emerging energy conversion has attracted significant attention. Fe-based single-atom catalysts (SACs) are efficient electrocatalysts for oxygen electrocatalysis on account of high intrinsic reaction activity, maximized metal atom utilization, well-defined active sites, customizable coordination environment, and regulable electronic structure. Although considerable performance improvements for Fe-based SACs in the oxygen electrocatalysis process have been made, the principle of modifying the electronic structure to promote the catalytic performance of Fe-based SACs is still ambiguous. In this review, the authors systematically summarize the regulation tactics for optimizing the catalytic activity and durability of Fe-based SACs toward oxygen electrocatalysis through different electronic structure adjustment methods, including the modulation of coordination atoms, metallic regulation, and the substrate effect. Ultimately, the challenges and future perspectives in the further development of Fe-based SACs are proposed.