Synergistic Integration of Intermediate Adsorption and Hydrogen Supply to Boost Nitrate Electroreduction to Ammonia Performance via Anchoring Nickel on Monolithic Copper Nanocone Arrays

ABSTRACT Electrocatalytic nitrate reduction to ammonia (NRA) is a sustainable approach for wastewater remediation and value‐added ammonia synthesis. The development of high‐performance electrocatalysts is crucial for practical implementation. Herein, we reported a rationally designed nickel‐anchored monolithic copper nanocone array (Ni/Cu‐NCAs) as an efficient NRA catalyst. The catalyst demonstrated outstanding NRA performance, achieving 96% nitrate conversion, 96.3% ammonium (NH 4 + )selectivity, 95.4% NH 4 + Faradaic Efficiency, and a high NH 4 + yield rate of 0.272 mmol·h −1 ·cm −2 . Combined experimental characterizations and density functional theory (DFT) calculations confirmed that the introduced Ni species modulated the d ‐band center of Cu sites to optimize the adsorption of key reaction intermediates, while simultaneously providing abundant active hydrogen (*H) for subsequent hydrogenation steps. The synergistic effect significantly accelerated reaction kinetics and promoted selective ammonia formation. This work developed a high‐efficiency monolithic Cu‐based NRA electrocatalyst, and shed new light on the bimetallic synergistic mechanism for nitrate electroreduction.