Engineering the Local Atomic Environments of Te‐Modulated Fe Single‐Atom Catalysts for High‐Efficiency O₂ Reduction

Abstract

Atomically dispersed metal‐nitrogen‐carbon materials (AD‐MNCs) are considered the most promising non‐precious catalysts for the oxygen reduction reaction (ORR), but it remains a major challenge for simultaneously achieving high intrinsic activity, fast mass transport, and effective utilization of the active sites within a single catalyst. Here, an AD‐MNCs consisting of defect‐rich Fe‐N3 sites dispersed with axially coordinated Te atoms on porous carbon frameworks (Fe1Te1‐900) is designed. The local charge densities and energy band structures of the neighboring Fe and Te atoms in FeN3‐Te are rearranged to facilitate the catalytic conversion of the O‐intermediates. Meanwhile, the negative shift of the d‐band center in FeN3‐Te reduces the energy barrier limit for effective desorption of the final OH* intermediate. In the electrochemical evaluation, Fe1Te1‐900 presents a more positive onset potential and half‐wave potentials of 1.03 and 0.89 V versus the reversible hydrogen electrode, respectively. Furthermore, the liquid zinc‐air batteries assembled with Fe1Te1‐900 exhibited excellent performances compared to commercial Pt/C. This work opens up new ideas for the development of high‐performance ORR electrocatalysts for applications in various energy conversion and storage technologies.