Electronic Modulation Induced by Ni‐VN Heterojunction Reinforces Electrolytic Hydrogen Evolution Coupled with Biomass Upgrade

Abstract The renewable electricity‐driven hydrogen evolution reaction (HER) coupled with biomass oxidation is a powerful avenue to maximize the energy efficiency and economic feedback, but challenging. Herein, porous Ni‐VN heterojunction nanosheets on nickel foam (Ni‐VN/NF) are constructed as a robust electrocatalyst to simultaneously catalyze HER and 5‐hydroxymethylfurfural electrooxidation reaction (HMF EOR). Benefiting from the surface reconstruction of Ni‐VN heterojunction during the oxidation process, the derived NiOOH‐VN/NF energetically catalyzes HMF into 2,5‐furandicarboxylic acid (FDCA), yielding the high HMF conversion (>99%), FDCA yield (99%), and Faradaic efficiency (>98%) at the lower oxidation potential along with the superior cycling stability. Ni‐VN/NF is also surperactive for HER, exhibiting an onset potential of ≈0 mV and Tafel slope of 45 mV dec −1 . The integrated Ni‐VN/NF||Ni‐VN/NF configuration delivers a compelling cell voltage of 1.426 V at 10 mA cm −2 for the H 2 O‐HMF paired electrolysis, about 100 mV lower than that for water splitting. Theoretically, for Ni‐VN/NF, the superiority in HMF EOR and HER is mainly dominated by the local electronic distribution at the heterogenous interface, which accelerates the charge transfer and optimize the adsorption of reactants/intermediates by modulating the d‐band center, therefore being an advisable thermodynamic and kinetic process.