The C–C bond cleavage inhibition and intermediates adsorption enhancement co-boost the selective electrooxidation of ethylene glycol on silver-palladium hollow nanocubes

Abstract

Efficient electrooxidation of ethylene glycol (EG) to glycolic acid (GA) is highly desirable for biomass valorization and EG recycling, which remains challenging owing to side reactions involving C–C bond cleavage. Herein, the bimetallic AgPd hollow nanocubes (AgPd hNCs) are successfully prepared via a solvothermal-assisted Galvanic replacement strategy. Both theoretical calculations and experimental results indicate that the electronic interplay between the Pd atom and Ag atom hinders C–C bond breaking and enhances the adsorption of critical intermediates, resulting in high selectivity toward GA production. Benefiting from these features, AgPd hNCs achieve a Faradaic efficiency of 93% toward GA formation and a 2.8-fold increase in mass activity compared to Pd black. Moreover, the strong oxygen affinity of Ag promotes the removal of CO-like intermediates from the Pd surface, resulting in superior EG oxidation stability. This study highlights a generalizable Ag-based strategy to modulate bimetallic interfaces for selective oxidation reaction of specific functional groups, contributing to the rational design of electrocatalysts for biomass upgrading.