Insights into lattice oxygen and strains of oxide-derived copper for ammonia electrosynthesis from nitrate

• Published in: Nature communications Vol. 16; no. 1; pp. 3479 - 12
• Main Authors: Wu, Qinyue, Fan, Xinfei, Shan, Bing, Qi, Liang, Quan, Xie, Liu, Yanming
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 11.04.2025; Nature Publishing Group; Nature Portfolio
• Subjects: 140/131; 140/133; 140/146; 140/58; 147/135; 147/143; 639/301/299/886; 639/638/161/886; 639/638/224/685; 704/172/169/896; Ammonia; Copper; Electronic structure; Humanities and Social Sciences; Hydrogen; Lattice strain; multidisciplinary; Nitrate reduction; Nitrates; Nitrogen dioxide; Oxygen; Recovery; Science; Science (multidisciplinary); Synthesis
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-025-58811-5

Electrocatalytic NO 3 − reduction (eNO3RR) is a sustainable method for purification of NO 3 − wastewater and NH 3 recovery. Cu-based catalysts are promising for eNO3RR, but insufficient active hydrogen (*H) supply and *NO 2 poison of active sites have hindered their performance, and the catalytic mechanism remains ambiguous. Here, we report oxide-derived copper nanosheet arrays (OD-Cu NSs) with residual lattice oxygen and lattice strains to enhance NH 3 synthesis from eNO3RR. It is efficient for NH 3 synthesis with high Faradaic efficiencies of 88.7-99.7% and maximum NH 3 yield of 6.20 mmol·h −1 ·cm −2 at neutral solution, 10-140 mM NO 3 − and 50-1500 mA·cm −2 . Experimental and theoretical results reveal that lattice oxygen regulates the electronic structure of OD-Cu NSs and promotes *NO 2 conversion, while lattice strain enhances *H generation from water dissociation, resulting in the good performance for NH 3 synthesis. The applicability of OD-Cu NSs is proved by the high recovery of ammonia compound from eNO3RR. Electrocatalytic nitrate reduction is promising for NH 3 synthesis, but it suffers from low NH 3 efficiency. Here, the authors report oxide-derived copper with residual lattice oxygen and lattice strains to enhance NH 3 synthesis via promoting active hydrogen supply and nitrite conversion.