Electrochemically-induced highly reactive PdO* interface on modulated mesoporous MOF-derived Co3O4 support for selective ethanol electro-oxidation

Abstract

Herein, Pd nanoparticles loaded Co3O4 catalysts (Pd@Co3O4) are constructed from zeolitic imidazolate framework-67 (ZIF-67) for the ethanol oxidation reaction (EOR). It is demonstrated for the first time that the electrochemical conversion of Co3O4 support would result in the charge distribution alignment at the Pd/Co3O4 interface and induce the formation of highly reactive Pd-O species (PdO*), which can further catalyze the consequent reactions of the intermediates of the ethanol oxidation. The catalyst, Pd@Co3O4-450, obtained under the optimized conditions exhibits excellent EOR performance with a high mass activity of 590 mA mg−1, prominent operational stability, and extraordinary capability for the electro-oxidation of acetaldehyde intermediates. Importantly, the detailed mechanism investigation reveals that Pd@Co3O4-450 could be benefit to the C–C bond cleavage to promote the desirable C1 pathway for the ethanol oxidation reaction. The present strategy based on the metal-support interaction of the catalyst might provide valuable inspiration for the design of high-performing catalysts for the ethanol oxidation reaction.