Construction of Fe–In Alloy to Enable High Activity and Durability of Fe–N–C Catalysts

The strategic regulation of the electronic properties and coordination environment of single‐atom sites through the integration of metal nanoclusters emerges as a promising route to enhance the oxygen reduction reaction (ORR) performance of Fe–N–C materials. Here, a catalyst (FeIn–NC) is successfully developed in which Fe–N–C materials encapsulate Fe–In alloy nanoclusters, and it shows excellent ORR activity and durability under alkaline conditions, with a high half‐wave potential of 0.924 V (vs RHE) and a zinc–air battery power density of 202.1 mW cm −2 , superior to commercial Pt/C catalysts. Theoretical calculations unravel that the synergistic interaction between the Fe–In alloy and the FeN 4 single‐atom site modifies the electronic structure and charge distribution at the FeN 4 site, thereby enhancing the electrocatalytic activity and durability of the ORR. Potential‐dependent microkinetic modeling (MKM) further discloses the ORR mechanisms on the identified FeN 4 sites. This work provides a viable strategy for the ORR improvement of Fe–N–C materials via p‐block metal‐based alloy nanoclusters.