Boosting Nitrate to Ammonia via the Optimization of Key Intermediate Processes by Low‐Coordinated Cu–Cu Sites

Abstract The electrochemical reduction of nitrate to ammonia (NO 3 RR) has emerged as a promising but challenging orientation in sustainable development. Cu is one of the most effective NO 3 RR catalysts. However, the accumulation of NO 2 − on their surface has erected bars to the further improvement of NO 3 RR efficiency. Herein, Cu‐based electrocatalyst with low‐coordinated Cu atoms (Cu‐LC) is synthesized via the instantaneous ablation and rapid cooling of the Cu target by pulse laser and proposed as a new NO 3 RR electrocatalyst, which exhibits enhanced NO 3 RR activity with NH 3 selectivity of 97.01%, yield rate of 0.624 mmol h −1 cm −2 at −0.8 V versus RHE and long‐term durability, superior to most reported Cu‐based catalysts. The introduction of low‐coordinated Cu sites upshifts the Cu d‐band center to near the Fermi Level, enhancing the adsorption of key intermediates ( * NO 2 , * NO) in NO 3 RR, and also effectively regulating the generation of * NO 2 and hydrogenation process, inhibiting the accumulation of NO 2 − on the Cu‐LC surface, thus achieving efficient NH 3 production. Furthermore, when evaluated as cathode material in Zn–NO 3 − battery, an open circuit voltage of 1.3 V and a power density of 3.1 mW cm −2 are achieved by the Cu‐LC‐based battery, highlighting a promising multifunctional system for ammonia production and energy supply.