Inspiration of Bimetallic Peroxide for Controllable Electrooxidizing Ethylene Glycol Through Modulating Surficial Intermediates

Biomass feedstock ethylene glycol (EG) can be anodically oxidized to the high-value glycolic acid (GA), which is widely considered as one critical raw material of biodegradable plastics. Developing low-cost electrocatalyst to economically produce GA with high selectivity still meeting challenges. Herein, a non-precious Co-Ni bimetal catalysts are developed for controllable electrooxidizing EG to GA (EGOR). Through regulating the generation of key intermediate (CH2OH-CO*) on the low-cost catalyst surface, a successive electrooxidation from EG to GA has been achieved with high selective (96.3%) and conversion rate (>85%) at current density of 150 mA cm(-2), which is on par with the reported precious metal catalysts. Through coupling with hydrogen evolution reaction (EGOR-HER), 2.759 mmol H-2 and 7.48 mmol of GA are generated at 80 mA cm(-2), which also can save 27% energy comparing with a water splitting system. The synergistic effect between Co and Ni in the bimetallic catalyst has been exploited: high-valent CoOOH sites catalyzed the generation of CH2OH-CO* and reduce the energy barrier during GA formation; Whereas, Ni sites can effectively facilitate the formation of CoOOH and improve the adsorption of EG.