Regulating H2O dissociation on Ni-doped Cu nanowires to promote electrocatalytic nitric oxide reduction to ammonia

Ni-doped Cu nanowires catalyst enables Cu sites to activate NO and Ni sites to accelerate water dissociation to supply *H. • In situ tests confirm Ni doping reduces charge transfer resistance, accelerates the Volmer step, and increases *H coverage. • CuNi 10% NWs catalyst has industrial-scale current density (>1000 mA cm −2 ) and 90.35% NH 3 Faradaic efficiency in a flow cell. • CuNi 10% NWs catalyst achieves 82.47% NH 3 Faradaic efficiency in a membrane electrode assembly with excellent stability. The electrocatalytic nitric oxide reduction reaction (NORR) presents a promising method for simultaneously mitigating nitric oxide (NO) pollution and synthesizing ammonia (NH 3 ). However, its practical application is hindered by sluggish kinetics, primarily due to inefficient water dissociation, which results in an inadequate supply of active hydrogen (*H) and thereby limits the hydrogenation of nitrogen-containing intermediates. Herein, we present Ni-doped Cu nanowires as a high-performance electrocatalyst for the NORR. The optimized catalyst with a Ni/(Ni + Cu) molar ratio of 10% (CuNi 10% NWs) delivers an industrial-scale current density exceeding 1000 mA cm −2 in a flow cell, achieving an exceptional Faradaic efficiency (FE) of 90.35% and an NH 3 yield rate of 6.84 mmol h −1 cm −2 (17.28 mmol g cat −1 h −1 ) at −1.0 V vs. reversible hydrogen electrode. Furthermore, in a membrane electrode assembly, the CuNi 10% NWs achieved an NH 3 FE of 82.47% and an NH 3 yield rate of 4.44 mmol h −1 cm −2 (8.88 mmol g cat −1 h −1 ). Remarkably, in situ electrochemical impedance spectroscopy and Tafel slope analyses reveal that Ni doping reduces the interfacial charge transfer resistance of Cu nanowires, accelerates the rate-determining Volmer step of water dissociation, and facilitates the generation and adsorption of *H intermediates. This study opens a new pathway for the resource utilization of industrial waste gas NO and the direct synthesis of NH 3 . Download: Download high-res image (156KB) Download: Download full-size image Ni-doped Cu nanowires catalyst acts as a high-efficiency catalyst for electrocatalytic NO-to-NH 3 conversion, where Cu sites activate NO and Ni sites accelerate water dissociation to enrich active hydrogen species, thus achieving superior catalytic activity for NH 3 synthesis.