Ligand‐Hybridization Activates Lattice‐Hydroxyl‐Groups of NiCo(OH)x Nanowires for Efficient Electrosynthesis

Abstract

AbstractElectrochemical dehydrogenation of hydroxides plays a crucial role in the formation of high‐valence metal active sites toward 5‐hydroxymethylfurfural oxidation reaction (HMFOR) to produce the value‐added chemical of 2,5‐furandicarboxylic (FDCA). Herein, we construct benzoic acid ligand‐hybridized NiCo(OH)x nanowires (BZ‐NiCo(OH)x) with ample electron‐deficient Ni/Co sites for HMFOR. The robust electron‐withdrawing capability of benzoic acid ligands in BZ‐NiCo(OH)x speeds up the electrochemical activation and dehydrogenation of lattice‐hydroxyl‐groups (M2+−O−H⇌M3+−O), boosting the formation of abundant electron‐deficient and high‐valence Ni/Co sites. DFT calculation reveals that the deintercalation proton is prone to establishing a hydrogen bridge with the carbonyl group in benzoic acid, facilitating the proton transfer. Coupled with the synergistic oxidation of Ni/Co sites on hydroxyl and aldehyde groups, BZ‐NiCo(OH)x delivers a remarkable current density of 111.20 mA cm−2 at 1.4 V for HMFOR, exceeding that of NiCo(OH)x by approximately fourfold. And the FDCA yield and Faraday efficiency are as high as 95.24 % and 95.39 %, respectively. The ligand‐hybridized strategy in this work introduces a novel perspective for designing high‐performance transition metal‐based electrocatalysts for biomass conversion.