Adjacent Copper Single Atoms Promote C-C Coupling in Electrochemical CO2 Reduction for the Efficient Conversion of Ethanol

Wei Xia; Yijun Xie; Shuaiqiang Jia; Shitao Han; Ruijuan Qi; Tao Chen; Xueqing Xing; Ting Yao; Dawei Zhou; Xue Dong; Jianxin Zhai; Jingjing Li; Jianping He; Dong Jiang; Yusuke Yamauchi; Mingyuan He; Haihong Wu; Buxing Han

doi:10.1021/jacs.3c04612

Adjacent Copper Single Atoms Promote C-C Coupling in Electrochemical CO₂ Reduction for the Efficient Conversion of Ethanol

J Am Chem Soc. 2023 Aug 9;145(31):17253-17264. doi: 10.1021/jacs.3c04612. Epub 2023 Jul 27.

Authors

Wei Xia¹, Yijun Xie¹, Shuaiqiang Jia¹, Shitao Han¹, Ruijuan Qi², Tao Chen³, Xueqing Xing⁴, Ting Yao¹, Dawei Zhou¹, Xue Dong¹, Jianxin Zhai¹, Jingjing Li⁵, Jianping He⁵, Dong Jiang⁶, Yusuke Yamauchi⁶, Mingyuan He¹, Haihong Wu¹, Buxing Han^{1

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Affiliations

¹ Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China.
² Key Laboratory of Polar Materials and Devices (MOE) and Department of Electronics Sciences, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China.
³ Research Center for Biomedical Optics and Molecular Imaging, Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
⁴ Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing Municipality 100049, China.
⁵ College of Materials Science and Technology, Jiangsu Key Laboratory of Electrochemical Energy-Storage Technologies, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
⁶ Department of Materials Process Engineering, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan.
⁷ Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
⁸ Institute of Eco-Chongming, 20 Cuiniao Road, Chenjia Town, Chongming District, Shanghai 202162, China.

PMID: 37498730
DOI: 10.1021/jacs.3c04612

Abstract

The electrochemical CO₂ reduction reaction (CO₂RR) using renewable electricity is one of the most promising strategies for reaching the goal of carbon neutrality. Multicarbonous (C₂₊) products have broad applications, and ethanol is a valuable chemical and fuel. Many Cu-based catalysts have been reported to be efficient for the electrocatalytic CO₂RR to C₂₊ products, but they generally offer limited selectivity and current density toward ethanol. Herein, we proposed a silica-mediated hydrogen-bonded organic framework (HOF)-templated approach to preparing ultrahigh-density Cu single-atom catalysts (SACs) on thin-walled N-doped carbon nanotubes (TWN). The content of Cu in the catalysts prepared by this method could be up to 13.35 wt %. It was found that the catalysts showed outstanding performance for the electrochemical CO₂RR to ethanol, and the Faradaic efficiency (FE) of ethanol increased with the increase in Cu-N₃ site density. The FE of ethanol over the catalysts with 13.35 wt % Cu could reach ∼81.9% with a partial current density of 35.6 mA cm^-2 using an H-type cell, which is the best result for electrochemical CO₂RR to ethanol to date. In addition, the catalyst could be stably used for more than 25 h. Experimental and density functional theory (DFT) studies revealed that the adjacent Cu-N₃ active sites (one Cu atom coordinates with three N) were the active sites for the reaction, and their high density was crucial for the high FE of ethanol because the adjacent Cu-N₃ sites with a short distance could promote the C-C coupling synergistically.