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Steering the nitrate electroreduction pathway via nanoconfinement-induced hydrogen-bond network regulation

Nature Water volume 4, pages 481–492 (2026) Cite this article

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Abstract

Electrochemical nitrate reduction to ammonia offers a sustainable route for wastewater remediation and fertilizer production. However, the prevailing hydrogen-atom-mediated pathway often suffers from low selectivity owing to competing hydrogen evolution. Here we show that nanoconfinement can fundamentally redirect the reaction pathway towards a highly efficient proton-coupled electron transfer process. We constructed a catalyst comprising CuCo alloy nanoparticles embedded within carbon nanotubes via flash joule heating. This architecture achieves an ammonia yield of 2.23 mg h−1 cm−2 with 93.8% Faradaic efficiency, surpassing non-confined counterparts. Mechanistic studies reveal that the nanoconfined microenvironment restructures the interfacial hydrogen-bond network to create a water-deficient, nitrate-enriched interface that suppresses water dissociation and facilitates direct proton shuttling. The system demonstrates robust stability in treating real wastewater, with technoeconomic and life-cycle analyses confirming its viability. This work establishes nanoconfinement as a powerful lever for steering interfacial environments and reaction pathways in electrocatalysis.

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Fig. 1: Schematic illustration of NO3RR and in situ NH3 recovery.
The alternative text for this image may have been generated using AI.
Fig. 2: Characterization and coordination structure information of CuCo-in-CNT and CuCo-out-CNT.
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Fig. 3: Electrocatalytic NO3RR performance.
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Fig. 4: Mechanistic investigation of CuCo-in-CNT and CuCo-out-CNT.
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Fig. 5: Theoretical calculations.
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Fig. 6: Application potential of flow-through device based on the CuCo-in-CNT electrode.
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Data availability

The data supporting the conclusions of this study are presented in the article and its Supplementary Information. Source data are provided with this paper.

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Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (grant no. W2412093 to Y.L.) and the Fundamental Research Funds for the Central Universities (grant no. DUT24RC(3)079 to Y.L.). We thank the Instrumental Analysis Centre of the Dalian University of Technology for the help on the TEM and scanning TEM characterization. We acknowledge the research group of M. Zhou at the Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, for providing access to instrumentation used for catalyst synthesis and quantification.

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Authors and Affiliations

  1. School of Environmental Science and Technology, Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), Dalian University of Technology, Dalian, People’s Republic of China

    Linghui Meng, Xin Wang, Yanming Liu, Meng Liu, Xie Quan & Yanbiao Liu

  2. College of Environmental Science and Engineering, Donghua University, Shanghai, People’s Republic of China

    Chensi Shen & Yanbiao Liu

  3. State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, People’s Republic of China

    Min Zhou

  4. Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, People’s Republic of China

    Chong-Chen Wang

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  1. Linghui Meng
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Contributions

Y.L. and L.M. designed research; L.M. performed the research; L.M., C.S., M.Z., X.W., Y.L., M.L. and Y.L. analysed data; and L.M., C-C.W., X.Q and Y.L. wrote the article.

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Correspondence to Yanbiao Liu.

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Nature Water thanks Rahman Daiyan and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Meng, L., Shen, C., Zhou, M. et al. Steering the nitrate electroreduction pathway via nanoconfinement-induced hydrogen-bond network regulation. Nat Water 4, 481–492 (2026). https://doi.org/10.1038/s44221-026-00600-5

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