La-Intercalation-Triggered Interfacial Electronic Redistribution in CoOOH Directs C2-Preserving Oxidation Pathways in Glycerol Electrooxidation

Abstract

Electrocatalytic glycerol oxidation offers a promising route to value-added oxygenates, but achieving pathway control beyond initial C─C cleavage remains a major challenge. Glycerol-derived C2 intermediates are prone to C─C over cleavage during subsequent oxidation, resulting in the formation of formate, which limits the selective production of oxalate. Herein, we develop an interfacial electronic redistribution strategy by intercalating oxophilic La3+ into layered cobalt oxyhydroxide (CoOOH) nanosheets to direct a C2-preserving oxidation pathway during glycerol electrooxidation. The engineered La-CoOOH achieves 94% glycerol conversion and an OA Faradaic efficiency of 68%, approaching the theoretical upper limit of 70%. Operando spectroscopy and density functional theory calculations indicate that interlayer La sites form La─O─Co interfacial bridges, which regulate the electronic structure of Co centers and facilitate OH– adsorption, thereby accelerating the dynamic regeneration of active Co(III)-OOH species. This electronic modification further tailors the adsorption configuration of glycerol-derived C2 intermediates, such that the free-energy change for C─C bond cleavage (0.39 eV) becomes less favorable than that for the hydroxyl-to-carboxyl oxidation of GCA* to OA* (0.05 eV). These findings highlight rare-earth-mediated interfacial electronic engineering as an effective strategy for redirecting glycerol electrooxidation toward C2-preserving oxalate formation.