Vacancy Optimized Coordination on Nickel Oxide for Selective Electrocatalytic Oxidation of Glycerol

The production of high-value-added organics by the glycerol oxidation reaction (GOR) holds significant research importance for addressing the surplus production of glycerol and mitigating the energy crisis. In this study, we report a vacancy optimized coordination on nickel oxide for the selective electrocatalytic oxidation of glycerol. Using in situ Raman and electron paramagnetic resonance spectroscopy, the formation of vacancies was traced during the cationic leaching process. Subsequently, in situ attenuated total reflection surface-enhanced IR absorption spectroscopy and density functional theory calculations revealed a significantly enhanced adsorption capacity and optimized co-adsorption process of OH^– and organics. Consequently, NiCrO with vacancies (NiCrO-V_Cr,O) exhibited GOR performance with conversion, formic acid selectivity, and faradaic efficiency values of 99%, 98%, and 96%, respectively. Notably, the conversion and selectivity in the flow electrolyzer remained above 90% during long-time continuous electrolysis, highlighting its industrial applicability. This study provides constructive guidance for the design of electrocatalysts, the optimization of the catalyst ligand environment, and the development of high-performance, metal-based catalysts for glycerol electro-oxidation.