Efficient Oxygen Reduction Catalysis on Fe ₄ Cluster Site Facilitated by Adjacent Single Atom

Abstract The inherent sluggish kinetics of the conventional four‐electron transfer pathway fundamentally limits the oxygen reduction reaction (ORR) efficiency. While electronic structure modulation offers potential solutions, developing effective catalytic regulation strategies remains challenging due to elusive structure‐activity correlations. In this study, Fe ₄ cluster sites are engineered with dual parallel electron transfer channels that enable concurrent O─O bond cleavage and dual oxygen atom protonation. This unique configuration facilitates an optimized two‐step double electron transfer mechanism, significantly enhancing ORR kinetics. Synergistic Mn single atom sites, strategically positioned as electron reservoirs, substantially elevate the electron density of Fe ₄ clusters while reinforcing Fe─N coordination bonds through charge redistribution. Remarkably, the spatial configuration of Fe ₄ clusters at the support periphery minimizes steric confinement effects, allowing simultaneous product desorption and oxygen adsorption – a critical advantage for sustaining continuous catalytic cycles. Through combined experimental and theoretical analyses, it is demonstrated that this dual‐channel electron transport system effectively reduces activation barriers for elementary steps while accelerating charge transfer kinetics. This fundamental study establishes a new paradigm for designing high‐performance ORR catalysts through multi‐site collaborative engineering and reaction pathway optimization.