Electrochemical ammonia synthesis via nitrate reduction on Fe single atom catalyst

• Published in: Nature communications Vol. 12; no. 1; pp. 2870 - 10
• Main Authors: Wu, Zhen-Yu, Karamad, Mohammadreza, Yong, Xue, Huang, Qizheng, Cullen, David A., Zhu, Peng, Xia, Chuan, Xiao, Qunfeng, Shakouri, Mohsen, Chen, Feng-Yang, Kim, Jung Yoon (Timothy), Xia, Yang, Heck, Kimberly, Hu, Yongfeng, Wong, Michael S., Li, Qilin, Gates, Ian, Siahrostami, Samira, Wang, Haotian
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 17.05.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 140/133; 140/146; 147/135; 147/143; 639/301/299; 639/638/77/886; 639/638/77/887; Ammonia; Catalysts; Density functional theory; Electrochemistry; Haber Bosch process; Humanities and Social Sciences; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; multidisciplinary; Nitrate reduction; Nitrates; Pollutants; Reaction mechanisms; Science; Science (multidisciplinary); Selectivity; Single atom catalysts; Water pollution
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-23115-x

Electrochemically converting nitrate, a widespread water pollutant, back to valuable ammonia is a green and delocalized route for ammonia synthesis, and can be an appealing and supplementary alternative to the Haber-Bosch process. However, as there are other nitrate reduction pathways present, selectively guiding the reaction pathway towards ammonia is currently challenged by the lack of efficient catalysts. Here we report a selective and active nitrate reduction to ammonia on Fe single atom catalyst, with a maximal ammonia Faradaic efficiency of ~ 75% and a yield rate of up to ~ 20,000 μg h −1 mg cat. −1 (0.46 mmol h −1 cm −2 ). Our Fe single atom catalyst can effectively prevent the N-N coupling step required for N 2 due to the lack of neighboring metal sites, promoting ammonia product selectivity. Density functional theory calculations reveal the reaction mechanisms and the potential limiting steps for nitrate reduction on atomically dispersed Fe sites. Developing green and delocalized routes for ammonia synthesis is highly important but still very challenging. Here the authors report an efficient ammonia synthesis process via nitrate reduction to ammonia on Fe single atom catalyst.