ABSTRACT The integration of electrocatalytic 5‐hydroxymethylfurfural (HMF) oxidation with the hydrogen evolution reaction (HER) is a win‐win strategy that enables the concurrent production of high‐value chemicals and low‐energy hydrogen. However, HMF oxidation suffers from competing adsorption between organics and OH − along with continuous redox cycling of active sites, leading to unsatisfactory activity, selectivity, and stability. To address these challenges, we designed a VO 2 /Ni 3 S 2 composite catalyst with rich cationic vacancies and low vanadium content. This catalyst creates Ni─V dual active sites that trigger an alternative reaction pathway. VO 2 /Ni 3 S 2 achieves high HMF conversion (97.1%), Faradaic efficiency (96.0%), and selectivity (98.93%) toward FDCA, along with robust stability. In an integrated HMFOR||HER system using VO 2 /Ni 3 S 2 for both electrodes, a current density of 100 mA cm −2 was attained at a low cell voltage of 1.76 V. Mechanistic studies reveal that VO 2 ‐induced vacancies promote the formation of high‐valence Ni species, while adjacent V sites enhance OH adsorption. This configuration enables balanced co‐adsorption of HMF and OH − . Unlike conventional single‐site Ni catalysis, the Ni─V dual sites optimize the dehydrogenation pathway while preserving the high oxidation state of Ni. This study sheds new light on the catalyst design for energy‐efficient biomass valorization and hydrogen production.
Zeng et al. (Fri,) studied this question.