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  • Review Article
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Nanofluidics for osmotic energy conversion

Nature Reviews Materials volume 6, pages 622–639 (2021)Cite this article

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Abstract

The osmotic pressure difference between river water and seawater is a promising source of renewable energy. However, current osmotic energy conversion processes show limited power output, mainly owing to the low performance of commercial ion-exchange membranes. Nanofluidic channels with tailored ion transport dynamics enable high-performance reverse electrodialysis to efficiently harvest renewable osmotic energy. In this Review, we discuss ion diffusion through nanofluidic channels and investigate the rational design and optimization of advanced membrane architectures. We highlight how the structure and charge distribution can be tailored to minimize resistance and promote energy conversion, and examine the possibility of integrating nanofluidic osmotic energy conversion with other technologies, such as desalination and water splitting. Finally, we give an outlook to future applications and discuss challenges that need to be overcome to enable large-scale, real-world applications.

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Fig. 1: Theoretical and practical milestones in nanofluidics for osmotic energy conversion.
Fig. 2: Nanofluidic channels for osmotic energy conversion.
Fig. 3: Surface charging principles.
Fig. 4: Advanced membrane architectures.
Fig. 5: Promoting osmotic energy conversion.
Fig. 6: Other energy conversion systems.
Fig. 7: Coupling with other technologies.

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Acknowledgements

This work was supported by the National Key R&D Program of China (2017YFA0206904, 2017YFA0206900) and the National Natural Science Foundation (21625303, 21905287, 21988102). Z.Z. acknowledges the support of the Alexander von Humboldt Foundation.

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  1. Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, P. R. China

    Zhen Zhang, Liping Wen & Lei Jiang

  2. Center for Advancing Electronics Dresden (cfaed) and Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Dresden, Germany

    Zhen Zhang

  3. School of Future Technology, University of Chinese Academy of Sciences, Beijing, P. R. China

    Liping Wen & Lei Jiang

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Zhang, Z., Wen, L. & Jiang, L. Nanofluidics for osmotic energy conversion. Nat Rev Mater 6, 622–639 (2021). https://doi.org/10.1038/s41578-021-00300-4

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