Facilitating C−C bond cleavage toward selective electrocatalytic oxidation of glycerol to formic acid: d−p orbital hybridization and adsorption thermodynamics

초록

Formic acid (FA) is a high-value product in hydrogen energy systems; hence, its selective production via electrochemical glycerol oxidation reaction (GOR) in an alkaline medium has emerged as an energy-efficient approach. However, the process is hindered by sluggish C−C bond cleavage, limited charge transfer, and competitive adsorption between glycerol and OH* species. In this study, we design La-based perovskite electrocatalysts with dual B-site metal incorporation to address the key challenges of alkaline GOR. Among various transition metal combinations (Ni, Fe, and Co), LaNi<inf>0.5</inf>Co<inf>0.5</inf>O<inf>3</inf> (LNCO) demonstrates the highest GOR performance due to a synergistic effect between Ni and Co, which has been shown to modulate the electronic structure and optimize adsorption thermodynamics. In particular, LNCO exhibits enhanced charge transfer behavior, driven by metal 3d−oxygen 2p orbital hybridization and by a delocalized electronic structure with negligible band gap. Furthermore, glycerol adsorption is thermodynamically more favorable than OH* species, providing balanced adsorption energy conducive to efficient GOR. Consequently, LNCO promotes C−C bond cleavage kinetics and enhances selective FA production. These findings highlight that LNCO is a promising electrocatalytic platform for value-added chemical synthesis via a sustainable electrochemical route. © 2025 Elsevier B.V., All rights reserved.

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