Scalable synthesis of coordinatively unsaturated metal-nitrogen sites for large-scale CO2 electrolysis

Ji Wei Sun; Xuefeng Wu; Peng Fei Liu; Jiacheng Chen; Yuanwei Liu; Zhen Xin Lou; Jia Yue Zhao; Hai Yang Yuan; Aiping Chen; Xue Lu Wang; Minghui Zhu; Sheng Dai; Hua Gui Yang

doi:10.1038/s41467-023-36688-6

Scalable synthesis of coordinatively unsaturated metal-nitrogen sites for large-scale CO₂ electrolysis

Nat Commun. 2023 Mar 23;14(1):1599. doi: 10.1038/s41467-023-36688-6.

Authors

Ji Wei Sun^#¹, Xuefeng Wu^#¹, Peng Fei Liu², Jiacheng Chen³, Yuanwei Liu¹, Zhen Xin Lou¹, Jia Yue Zhao¹, Hai Yang Yuan¹, Aiping Chen¹, Xue Lu Wang⁴, Minghui Zhu³, Sheng Dai⁵, Hua Gui Yang⁶

Affiliations

¹ Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
² Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China. pfliu@ecust.edu.cn.
³ State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
⁴ Physics Department and Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China.
⁵ Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China. shengdai@ecust.edu.cn.
⁶ Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China. hgyang@ecust.edu.cn.

^# Contributed equally.

Abstract

Practical electrochemical CO₂-to-CO conversion requires a non-precious catalyst to react at high selectivity and high rate. Atomically dispersed, coordinatively unsaturated metal-nitrogen sites have shown great performance in CO₂ electroreduction; however, their controllable and large-scale fabrication still remains a challenge. Herein, we report a general method to fabricate coordinatively unsaturated metal-nitrogen sites doped within carbon nanotubes, among which cobalt single-atom catalysts can mediate efficient CO₂-to-CO formation in a membrane flow configuration, achieving a current density of 200 mA cm^-2 with CO selectivity of 95.4% and high full-cell energy efficiency of 54.1%, outperforming most of CO₂-to-CO conversion electrolyzers. By expanding the cell area to 100 cm², this catalyst sustains a high-current electrolysis at 10 A with 86.8% CO selectivity and the single-pass conversion can reach 40.4% at a high CO₂ flow rate of 150 sccm. This fabrication method can be scaled up with negligible decay in CO₂-to-CO activity. In situ spectroscopy and theoretical results reveal the crucial role of coordinatively unsaturated metal-nitrogen sites, which facilitate CO₂ adsorption and key *COOH intermediate formation.