Fe/Cu diatomic catalysts for electrochemical nitrate reduction to ammonia

Shuo Zhang; Jianghua Wu; Mengting Zheng; Xin Jin; Zihan Shen; Zhonghua Li; Yanjun Wang; Quan Wang; Xuebin Wang; Hui Wei; Jiangwei Zhang; Peng Wang; Shanqing Zhang; Liyan Yu; Lifeng Dong; Qingshan Zhu; Huigang Zhang; Jun Lu

doi:10.1038/s41467-023-39366-9

Fe/Cu diatomic catalysts for electrochemical nitrate reduction to ammonia

Nat Commun. 2023 Jun 19;14(1):3634. doi: 10.1038/s41467-023-39366-9.

Authors

Shuo Zhang^{1

2

3}, Jianghua Wu², Mengting Zheng⁴, Xin Jin², Zihan Shen¹, Zhonghua Li², Yanjun Wang², Quan Wang², Xuebin Wang², Hui Wei², Jiangwei Zhang⁵, Peng Wang^{2

6}, Shanqing Zhang⁴, Liyan Yu³, Lifeng Dong³, Qingshan Zhu^{7

8}, Huigang Zhang^{9

10

11}, Jun Lu¹²

Affiliations

¹ State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.
² National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China.
³ College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
⁴ Centre for Clean Environment and Energy and Griffith School of Environment, Griffith University, Gold Coast, QLD, 4222, Australia.
⁵ Dalian National Laboratory for Clean Energy & State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS), Dalian, 116023, China.
⁶ Department of Physics, University of Warwick, Coventry, CV4 7AL, UK.
⁷ State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China. qszhu@ipe.ac.cn.
⁸ School of Chemical Engineering, University of the Chinese Academy of Sciences, No. 19(A) Yuquan Road, Shijingshan District, Beijing, 100049, PR China. qszhu@ipe.ac.cn.
⁹ State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China. hgzhang@ipe.ac.cn.
¹⁰ National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China. hgzhang@ipe.ac.cn.
¹¹ School of Chemical Engineering, University of the Chinese Academy of Sciences, No. 19(A) Yuquan Road, Shijingshan District, Beijing, 100049, PR China. hgzhang@ipe.ac.cn.
¹² College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, Zhejiang Province, 310027, China. junzoelu@zju.edu.cn.

Abstract

Electrochemical conversion of nitrate to ammonia offers an efficient approach to reducing nitrate pollutants and a potential technology for low-temperature and low-pressure ammonia synthesis. However, the process is limited by multiple competing reactions and NO₃^- adsorption on cathode surfaces. Here, we report a Fe/Cu diatomic catalyst on holey nitrogen-doped graphene which exhibits high catalytic activities and selectivity for ammonia production. The catalyst enables a maximum ammonia Faradaic efficiency of 92.51% (-0.3 V(RHE)) and a high NH₃ yield rate of 1.08 mmol h^-1 mg^-1 (at - 0.5 V(RHE)). Computational and theoretical analysis reveals that a relatively strong interaction between NO₃^- and Fe/Cu promotes the adsorption and discharge of NO₃^- anions. Nitrogen-oxygen bonds are also shown to be weakened due to the existence of hetero-atomic dual sites which lowers the overall reaction barriers. The dual-site and hetero-atom strategy in this work provides a flexible design for further catalyst development and expands the electrocatalytic techniques for nitrate reduction and ammonia synthesis.