Electron Transfer from Encapsulated Fe3C to the Outermost N‐Doped Carbon Layer for Superior ORR

Abstract Encapsulating Fe 3 C in carbon layers has emerged as an innovative strategy for protecting Fe 3 C while preserving its high oxygen reduction activity. However, fundamental questions persist regarding the active sites of encapsulated Fe 3 C due to the restricted accessibility of oxygen molecules to the metal sites. Herein, the intrinsic electron transfer mechanisms of Fe 3 C nanoparticles encapsulated in N‐doped carbon materials are unveiled for oxygen reduction electrocatalysis. The precision‐structured C 1 N 1 material is used to synthesize N‐doped carbons with encapsulated Fe 3 C, significantly enhancing catalytic activity (E ONSET = 0.98 V) and achieving near‐100% operational stability. In anion‐exchange membrane fuel cells, an excellent peak power density of 830 mW cm −2 is reached at 60 °C. The experimental and computational results revealed that the presence of Fe 3 C cores dynamically triggers electron transfer to the outermost carbon layer. This phenomenon amplifies the oxygen reduction reaction performance at N sites, contributing significantly to the observed catalytic enhancement.