Amidst the global imperative for clean energy transition, electrocatalytic water splitting faces efficiency constraints due to sluggish oxygen evolution reaction (OER) kinetics. While defect engineering enhances OER catalysis, conventional single-/dual-defect systems have inherent optimization limitations. Herein, we engineer atomically thin CoOOH nanosheets as programmable carriers for a triple-defect coordination system (Mn2+/W6+ dopants with Co vacancies). This unique ultrathin architecture, integrating heteroatom dopants and cationic vacancies, overcomes conventional characterization barriers by enabling atomic-scale imaging. Advanced structural analysis directly visualizes and confirms the multidefect configurations. Electrochemical assessment demonstrates exceptional activity (overpotential: 286 mV @ 10 mA cm-2) and stability (>100 h), while density functional theory (DFT) calculations reveal the mechanism of multidefect-synergy intermediate binding energy optimization─positioning the Gibbs free energy change of O (ΔGO) nearly midway between ΔGOH and ΔGOOH. This work establishes a paradigm for rational electrocatalyst design by visualizing atomic-level multidefect interplay.
Deng et al. (2026) studied this question.