Synergistic Lattice Oxygen Stabilization and Deprotonation Kinetics Acceleration Via Fluorine Incorporation for Durable Acidic Oxygen Evolution

ABSTRACT The implementation of cost‐effective and active ruthenium dioxide (RuO 2 )‐based catalysts in proton exchange membrane water electrolyzers (PEMWEs) is hindered by their insufficient stability, primarily due to uncontrollable loss of the lattice oxygen during OER operation. To address this challenge, a non‐metallic fluorine doping strategy is developed to stabilize the lattice oxygen, controlling a low participation of lattice oxygen and simultaneously enhancing catalytic performance. Theoretical calculations and in situ spectroscopy measurements reveal that electron‐withdrawing F weakens lattice oxygen reactivity and enhances its proton affinity, suppressing the lattice oxygen mechanism (LOM) pathway while accelerating the deprotonation kinetics, thereby leading to simultaneous improvements in both stability and activity. The optimized F‐RuO 2 catalyst achieves a remarkably low overpotential of 198 mV at 10 mA cm − 2 and exceptional durability with a negligible degradation rate of 15 µV h − 1 within 600 h. When integrated into a PEMWE, it requires only 1.80 V to deliver a high current density of 3 A cm − 2 and maintains stable operation for over 850 h at 100 mA cm − 2 . This work provides a feasible strategy to break the activity‐stability trade‐off of OER electrocatalysts through rational regulation of lattice oxygen behavior, facilitating the industrial adoption of RuO 2 ‐based catalysts in PEMWEs.