Journal of the American Chemical Society · 2025 · 80 citations · 51 references
Natural SciencesChemistryMaterials ScienceCatalysisInorganic ChemistrySurface ScienceCatalyst DesignCatalytic MaterialsRedox CatalysisRedox-active MaterialsSurface CatalysisSurface OxidationIridium-based Oxygen Evolution CatalystsMesoporous MaterialsMesoporous NanomaterialsOxygen Evolution CatalystsOxygen Evolution ReactionPourbaix DiagramsStructural StabilityWater Electrolysis
High Resolution Image Download MS PowerPoint Slide The scarcity of iridium (Ir) limits its widespread use in acidic oxygen evolution reaction (OER). Herein, mesoporous single-crystalline spinel Co 3 O 4 with atomically dispersed low-valence-state Ir has been developed to enable Ir’s efficient and stable utilization. The surface Pourbaix diagram suggests that under acidic OER conditions, O* fully covers both Co 3 O 4 (111) and (110) surfaces, passivating Co sites but enhancing Co 3 O 4 ’s structural stability, a benefit further improved by Ir doping. Mesopores offer numerous loading sites for Ir single atoms (13.8 wt %), which activate the originally O*-passivated Co 3 O 4 (111) surface by creating high-intrinsic-activity Co–Ir bridge sites; meanwhile, Ir and Co leaching rates are reduced to about 1/4 and 1/5, respectively, compared to conventional Ir/Co 3 O 4 catalysts. Our catalyst exhibits a low η 10 of 248 mV for over 100 h, showcasing its potential in water electrolysis.
51