Dynamic Charge Storage via Gallium Mediation: Tuning Lewis Acidity of Atomic Dispersed Fe Sites for Enhanced Fuel Cell Performance

ABSTRACT Iron and nitrogen co‐doped carbon material (Fe–N–C) catalysts hold great promise as cost‐effective alternatives to platinum but are fundamentally constrained in catalytic performance by linear scaling relationships among intermediate adsorption energies. Herein, we report a Ga‐mediated dynamic charge storage strategy to precisely regulate the Lewis acidity of Fe centers, dynamically enabling * O 2 activation and * OH desorption. Ga atoms, characterized by moderate high occupied molecular orbital‐lowest unoccupied molecular orbital (HOMO‐LUMO) gap, establish an electron‐transfer channel with Fe, acting as a charge reservoir to neutralize intermediates‐ triggered charge polarization of Fe sites. This flexible electron regulation allows Fe centers to switch between weak Lewis acid sites with enhanced electron‐donating ability and strong Lewis acid sites with reduced electron‐donating ability, thereby overcoming the conventional adsorption‐desorption trade‐off and achieving accelerated reaction kinetics. The as‐synthesized catalyst demonstrates outstanding electrocatalytic performance, retaining 92.4% of its current density after 500 h in acidic media. It delivers current densities of 147.09 mA cm −2 @0.8 V iR‐free and 670.31 mA cm −2 @0.675 V iR‐free , significantly exceeding United States Department of Energy (U.S.DOE) targets by ∼1.5‐ and ∼1.3‐fold, and achieving a peak power density of 0.78 W cm −2 at H 2 ‐air fuel cells. This work deciphers dynamic charge storage as a conceptual framework for decoupling adsorption energetics and overcoming linear scaling relationships in multi‐step reactions.