Modulating Ni‐O‐V Bridges in NiV‐Layered Double Hydroxides Microspheres for Robust Electrocatalytic Coupling of 1,5‐Pentanediol Oxidation and Nitrate Reduction

Abstract

ABSTRACT The co‐electrolysis system that couples anodic oxidation of biomass‐derived polyols with cathodic nitrate reduction reaction (NO 3 RR) represents a promising strategy for biomass valorization and treatment of high‐salinity wastewater. Here, we synthesize thin NiV‐layered double hydroxides (NiV‐LDHs) microspheres featuring engineered Ni‐O‐V bridge structures as dual‐channel electrocatalysts. The newly constructed Ni‐O‐V bridges confirmed by x‐ray absorption spectroscopy effectively modulate the electronic structures of both Ni and V sites. This synergistic enhancement boosts the performance of both anodic 1,5‐pentanediol electrooxidation to produce glutaric acid (GA) and NO 3 RR to ammonia. The NiV‐LDHs anode enables electrolysis at a low cell voltage of 1.5 V versus RHE, exhibiting a GA Faradaic efficiency of 98.5% and a high GA yield of 2.56 mmol h −1 cm −2 . Operando studies and density functional theory reveal that the strong electronic coupling within NiV‐LDHs optimizes the competitive adsorption between 1,5‐pentanediol and OH* on the catalyst surface. Moreover, the NiV‐LDHs cathode exhibits outstanding NO 3 RR performance, achieving a high ammonia yield of 2.28 mmol h −1 cm −2 with a Faradaic efficiency of 96.1%, surpassing most reported electrocatalysts. A continuous paired electrolysis operation over 240 h successfully produced GA (55.98 g) and NH 4 Cl (23.48 g) powders, demonstrating great potential for industrial application.