Revealing and modulating catalyst reconstruction for highly efficient electrosynthesis of ammonia

• Published in: Nature communications Vol. 16; no. 1; pp. 6161 - 15
• Main Authors: Shi, Xinyue, Huang, Wei-Hsiang, Rong, Ju, Xie, Minghui, Wa, Qingbo, Zhang, Ping, Wei, Hainan, Zhou, Huangyu, Yeh, Min-Hsin, Pao, Chih-Wen, Wang, Jie, Hu, Zhiwei, Yu, Xiaohua, Ma, Jiwei, Cheng, Hongfei
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 04.07.2025; Nature Publishing Group; Nature Portfolio
• Subjects: 140/133; 140/146; 639/301/299/886; 639/638/161/886; 639/638/77/886; Absorption spectroscopy; Accumulation; Adsorption; Ammonia; Catalysts; Cobalt; Electric fields; Electrons; Energy; Fourier transforms; Humanities and Social Sciences; Hydrogenation; multidisciplinary; Nitrate reduction; Nitrates; Oxidation; Reconstruction; Science; Science (multidisciplinary); Spectrum analysis; Stability; Synthesis; Transmission electron microscopy; Wavelet transforms; X ray absorption; X-ray absorption spectroscopy
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-025-61075-8

Electrocatalytic nitrate reduction (NO 3 RR) is a promising route for sustainable ammonia synthesis under mild conditions. The widely studied Co-based catalysts undergo significant reconstruction due to nitrate oxidation and electric-field reduction during NO 3 RR, leading to activity degradation. To address this issue, we develop a Co 6 Ni 4 heterostructured catalyst that consists of interlaced metallic Co and Ni domains. Operando X-ray absorption spectroscopy and other in-situ characterization techniques, in conjunction with theoretical calculations, demonstrate that Ni domains function as electron reservoir, which transfer electrons to Co and prevent the accumulation of high-valence Co. Besides, the abundant Co/Ni interfaces also facilitate the NO 3 RR process, thereby achieving a NH 3 Faraday efficiency of 99.21%, a NH 3 yield rate of 93.55 mg h -1 cm -2 , and a NO 3 RR stability of 120 h. Our analyses delve into the underlying causes of the observed stability of metallic Co in Co 6 Ni 4 and provide compelling evidence that the discrepancy between the adsorption quantity of NO 3 - on catalyst surface and the corresponding electron supply is a pivotal factor influencing the reconstruction process. During electrocatalytic nitrate reduction, cobalt-based catalysts degrade fast due to the combined effect of nitrate oxidation and electric-field reduction. Here, the authors develop a Co6Ni4 heterostructured catalyst to prevent high valence Co accumulation and achieve efficient ammonia synthesis.