Abstract
The challenge in precisely controlling the adsorption configuration of oxygen-binding intermediates in the branching path following C–C coupling constrains the directed selectivity of electroreduction CO2-to-ethanol. Here, we present a subsurface Co-doped CuS (Co-Sub-CuS) catalyst, which exhibits directed selectivity toward ethanol. We elucidate the role of subsurface doping in enhancing the oxophilicity of surface Cu sites, thereby facilitating the conversion of key intermediates (*CHCHO*) via the formation of surface-O bonds, guiding subsequent protonation towards ethanol. Moreover, the surface sulfur vacancies created by subsurface Co-doping help regulate the optimal distance between dual sites, facilitating asymmetric C–C coupling. Theoretical calculations combin…
Abstract
The challenge in precisely controlling the adsorption configuration of oxygen-binding intermediates in the branching path following C–C coupling constrains the directed selectivity of electroreduction CO2-to-ethanol. Here, we present a subsurface Co-doped CuS (Co-Sub-CuS) catalyst, which exhibits directed selectivity toward ethanol. We elucidate the role of subsurface doping in enhancing the oxophilicity of surface Cu sites, thereby facilitating the conversion of key intermediates (*CHCHO*) via the formation of surface-O bonds, guiding subsequent protonation towards ethanol. Moreover, the surface sulfur vacancies created by subsurface Co-doping help regulate the optimal distance between dual sites, facilitating asymmetric C–C coupling. Theoretical calculations combined with in-situ isotopic spectroscopy validate these views, and the branching pathway for converting *CHCO to *CHCHO* is captured. Consequently, in a membrane electrode assembly electrolyzer, the optimized Co-Sub-CuS achieves an ethanol Faradaic efficiency of 78.7% at a partial current density of 550.9 mA cm-2, with stability over 305 h at industrial-level current density of 700 mA cm-2. These findings provide a rational design for the development of directionally selective catalysts for CO2 electroreduction.
Data availability
All data that support the findings in this paper are available within the article and its Supplementary Information or are available from the corresponding authors upon reasonable request. Source data are provided with this paper.
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Acknowledgements
This work was supported by the Joint Funds of the National Natural Science Foundation of China (U24A20513 to G.F.W.), the key project of National Natural Science Foundation of China (21936001 to G.F.W.) and National Natural Science Foundation of China (22176001, 52192684 to X.J.Z. and G.F.W.), the Opening Project of State Key Laboratory of High Performance Ceramics and Superfine Microstructure (SKL202205SIC to X.J.Z.).
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Author notes
These authors contributed equally: Ming-Zheng Gu, Yuan Min.
Authors and Affiliations
Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials, Anhui Engineering Research Center of Carbon Neutrality, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui, China
Ming-Zheng Gu, Ling Jiang, Fu Zhou, Qiao Chen, Xiao-Jun Zhang & Guang-Feng Wang 1.
State Key Laboratory of Advanced Environmental Technology, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, Anhui, China
Yuan Min, Jie-Jie Chen & Han-Qing Yu 1.
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China
Xiao-Jun Zhang
Authors
- Ming-Zheng Gu
- Yuan Min
- Ling Jiang
- Fu Zhou
- Qiao Chen
- Xiao-Jun Zhang
- Jie-Jie Chen
- Han-Qing Yu
- Guang-Feng Wang
Contributions
M.Z.G., G.F.W., X.J.Z., J.J.C. and H.Q.Y. conceived and designed the research; M.Z.G. conducted the synthesis and characterization. M.Z.G. and F.Z. analyzed the data and relevant results. Y.M. performed the DFT calculations. M.Z.G. and L.J. performed the electrochemical experiments. M.Z.G. and Q.C. performed and discussed soft X-ray absorption spectroscopy characterization. G.F.W., X.J.Z., J.J.C. and H.Q.Y. contributed to the planning and coordination of the project. M.Z.G., F.Z., G.F.W., X.J.Z., J.J.C. and H.Q.Y. co-wrote and edited the manuscript. All the authors contributed to the discussion of the results and the manuscript.
Corresponding authors
Correspondence to Jie-Jie Chen, Han-Qing Yu or Guang-Feng Wang.
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Cite this article
Gu, MZ., Min, Y., Jiang, L. et al. Subsurface engineering for directional-selective CO₂-to-ethanol electrocatalysis at industrial-level. Nat Commun (2025). https://doi.org/10.1038/s41467-025-67176-8
Received: 11 March 2025
Accepted: 20 November 2025
Published: 06 December 2025
DOI: https://doi.org/10.1038/s41467-025-67176-8