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Designing catalysts with highly active, selectivity, and stability for electrocatalytic CO2 to formate is currently a severe challenge. Herein, we developed an electronic structure engineering on carbon nano frameworks embedded with nitrogen and sulfur asymmetrically dual-coordinated indium active sites toward the efficient electrocatalytic CO2 reduction reaction. As expected, atomically dispersed In-based catalysts with In-S1N3 atomic interface with asymmetrically coordinated exhibited high efficiency for CO2 reduction reaction (CO2RR) to formate. It achieved a maximum Faradaic efficiency (FE) of 94.3% towards formate generation at −0.8 V vs. reversible hydrogen electrode (RHE), outperforming that of catalysts with In-S2N2 and In-N4 atomic interface. And at a potential of −1.10 V vs. RHE, In-S1N3 achieves an impressive Faradaic efficiency of 93.7% in flow cell. The catalytic performance of In-S1N3 sites was confirmed to be enhanced through in-situ X-ray absorption near-edge structure (XANES) measurements under electrochemical conditions. Our discovery provides the guidance for performance regulation of main group metal catalysts toward CO2RR at atomic scale.


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Asymmetrically coordinated main group atomic In-S1N3 interface sites for promoting electrochemical CO2 reduction

Show Author's information Yan Gao1( )Jinlong Ge1Jingqiao Zhang2,3Ting Cao2,3Zhiyi Sun5Wensheng Yan6Yu Wang7Jie Lin4( )Wenxing Chen5Zheng Liu2,3( )
Anhui Provincial Engineering Laboratory of Silicon-based Materials, Bengbu University, Bengbu 233030, China
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
SEPA Key Laboratory of Eco-Industry, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Science, Ningbo 315201, China
Energy & Catalysis Center, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China
Shanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Science, Shanghai 201204, China

Abstract

Designing catalysts with highly active, selectivity, and stability for electrocatalytic CO2 to formate is currently a severe challenge. Herein, we developed an electronic structure engineering on carbon nano frameworks embedded with nitrogen and sulfur asymmetrically dual-coordinated indium active sites toward the efficient electrocatalytic CO2 reduction reaction. As expected, atomically dispersed In-based catalysts with In-S1N3 atomic interface with asymmetrically coordinated exhibited high efficiency for CO2 reduction reaction (CO2RR) to formate. It achieved a maximum Faradaic efficiency (FE) of 94.3% towards formate generation at −0.8 V vs. reversible hydrogen electrode (RHE), outperforming that of catalysts with In-S2N2 and In-N4 atomic interface. And at a potential of −1.10 V vs. RHE, In-S1N3 achieves an impressive Faradaic efficiency of 93.7% in flow cell. The catalytic performance of In-S1N3 sites was confirmed to be enhanced through in-situ X-ray absorption near-edge structure (XANES) measurements under electrochemical conditions. Our discovery provides the guidance for performance regulation of main group metal catalysts toward CO2RR at atomic scale.

Keywords: structure–activity relationship, CO2 reduction reaction, indium single-site catalyst, main group metal, asymmetrical coordination

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Publication history
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Acknowledgements

Publication history

Received: 29 November 2023
Revised: 20 January 2024
Accepted: 23 January 2024
Published: 07 March 2024
Issue date: June 2024

Copyright

© Tsinghua University Press 2024

Acknowledgements

Acknowledgements

This work was supported by the Anhui Provincial Department of Education (No. KJ2021A1125), the National Natural Science Foundation of China (No. 12374390), Ningbo 3315 Innovative Teams Program (No. 2019A-14-C), and the member of Youth Innovation Promotion Association Foundation of CAS, China (No. 2023310). The authors thank the BL14W1 in the Shanghai Synchrotron Radiation Facility (SSRF), BL10B and BL12B in the National Synchrotron Radiation Laboratory (NSRL) for help with characterizations.

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