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Acidic oxygen reduction by single-atom Fe catalysts on curved supports

Nature volume 644, pages 668–675 (2025) Cite this article

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Abstract

Developing highly active and durable electrocatalysts for cost-effective proton-exchange membrane fuel cells is challenging1,2,3. Fe/N–C catalysts are among the most promising alternatives to the platinum group metal catalysts, but their activity and durability still cannot meet the performance criteria due to the strong adsorption of oxygenated reaction intermediates and the demetallization of Fe species caused by the Fenton reaction4,5,6,7,8. Here we design and develop a new type of Fe/N–C catalyst that is composed of numerous nanoprotrusions dispersed on two-dimensional carbon layers with single Fe-atom sites primarily embedded within the inner curved surface of the nanoprotrusions. The graphitized outer carbon layer of the nanoprotrusions can not only effectively weaken the binding strength of the oxygenated reaction intermediates, but also reduce the hydroxyl radical production rate. As a result, the Fe/N–C catalyst delivers one of the best-performing platinum group metal-free proton-exchange membrane fuel cell performances, achieving a record high power density of 0.75 W cm−2 under 1.0 bar H2–air with 86% activity retention after more than 300 hours of continuous operation.

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Fig. 1: Characterization of the CS Fe/N–C.
The alternative text for this image may have been generated using AI.
Fig. 2: Structural characterization of the CS Fe/N–C.
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Fig. 3: DFT simulations.
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Fig. 4: Fuel cell performance.
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Fig. 5: In-depth understanding of the activity and stability improvements by in situ measurements.
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Data availability

The data that support the findings of this study have been included in the main text and the Supplementary Information, and are available from the corresponding authors upon request.

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Acknowledgements

This work was supported by the National Key R&D Program of China (grant no. 2024YFA1509400), the National Natural Science Foundation of China (grant nos. 22293043, 52201284 and 92163209), Shenzhen University 2035 Program for Excellent Research (grant no. 2024B005), the City University of Hong Kong startup fund (grant no. 9020003), ITF–RTH—Global STEM Professorship (grant no. 9446006) and JC STEM laboratory of Advanced CO2 Upcycling (grant no. 9228005). J.W. acknowledges support from the National Key Research and Development Program of China (grant no. 2022YFA1503103) and the Natural Science Foundation of China (grant nos. 22033002, 9226111 and 22422303). X.L. acknowledges support from the Strategic Priority Research Program of the Chinese Academy of Sciences (grant no. XDB0600200).

Author information

Author notes

  1. These authors contributed equally: Yasong Zhao, Jiawei Wan, Chongyi Ling, Yanlei Wang

Authors and Affiliations

  1. State Key Laboratory of Biopharmaceutical Preparation and Delivery, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, People’s Republic of China

    Yasong Zhao, Jiawei Wan, Nailiang Yang & Dan Wang

  2. State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, People’s Republic of China

    Yasong Zhao & Dan Wang

  3. Key Laboratory of Quantum Materials and Devices of Ministry of Education, School of Physics, Southeast University, Nanjing, People’s Republic of China

    Chongyi Ling & Jinlan Wang

  4. Beijing Key Laboratory of Ionic Liquids Clean Process, State Key Laboratory of Multiphase Complex Systems, CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, People’s Republic of China

    Yanlei Wang, Hongyan He & Suojiang Zhang

  5. Key Laboratory of Molecular Nanostructure and Nanotechnology, Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, People’s Republic of China

    Rui Wen

  6. Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, People’s Republic of China

    Qinghua Zhang

  7. School of Materials Science and Engineering, Tsinghua University, Beijing, People’s Republic of China

    Lin Gu

  8. State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, People’s Republic of China

    Bolong Yang & Zhonghua Xiang

  9. Department of Chemistry, Tsinghua University, Beijing, People’s Republic of China

    Chen Chen

  10. Department of Chemistry, City University of Hong Kong, Hong Kong SAR, People’s Republic of China

    Xin Wang & Bin Liu

  11. College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, People’s Republic of China

    Yucheng Wang & Huabing Tao

  12. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, People’s Republic of China

    Xuning Li

  13. Department of Materials Science and Engineering, Hong Kong Institute for Clean Energy (HKICE) and Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong SAR, People’s Republic of China

    Bin Liu

Authors
  1. Yasong Zhao
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Contributions

D.W. conceived the idea, supervised the project, discussed the experimental results, analysed the data and drafted the paper. Y.Z. performed the catalyst synthesis, structural characterization, electrochemical measurements and drafted the paper. J. Wan carried out the XANES fitting. C.L. and J. Wang conducted the DFT calculations and analysis. Yanlei Wang, H.H. and S.Z. performed the preliminary calculations. N.Y. and C.C. provided constructive suggestions. R.W. conducted the AFM measurements. Q.Z. and L.G. conducted the aberration-corrected STEM measurements. B.Y. and Z.X. conducted the fuel cell measurements and analysed the data. Yucheng Wang conducted the EPR measurements. H.T. conducted the EIS measurements. X.L. conducted the Mössbauer spectroscopy measurements. B.L. and X.W. provided insightful suggestions and improved the paper.

Corresponding authors

Correspondence to Zhonghua Xiang, Jinlan Wang, Bin Liu, Suojiang Zhang or Dan Wang.

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Nature thanks Boyang Li, Quentin Meyer and Daixin Ye for their contribution to the peer review of this work.

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Supplementary Figs. 1–50 and Tables 1–10.

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Zhao, Y., Wan, J., Ling, C. et al. Acidic oxygen reduction by single-atom Fe catalysts on curved supports. Nature 644, 668–675 (2025). https://doi.org/10.1038/s41586-025-09364-6

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