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Matter in ångström-scale two-dimensional confinement

Nature Reviews Chemistry (2026)Cite this article

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An Author Correction to this article was published on 31 March 2026

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Abstract

Matter exhibits strikingly different structures and behaviours in strongly confined spaces compared with its bulk form. These differences become particularly pronounced when the confinement is reduced to the ångström scale, comparable with the characteristic size of atoms, ions and molecules. Advances in layered two-dimensional (2D) materials — including both van der Waals and non-van-der-Waals materials — have enabled the precise fabrication of ångström-scale 2D confinement systems, opening a new frontier for investigating matter properties and mass transport at this extreme scale. In this Review, we summarize the methods used for precisely fabricating such confined systems, the novel structural transformations of matter that arise and their associated physicochemical properties, and the unique molecular and ionic transport phenomena observed and their underlying mechanisms. We also critically assess the knowledge gaps, technological implications and untapped potential of this burgeoning field.

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Fig. 1: Characteristic parameters of atoms, molecules and ions.
Fig. 2: Building ångström-scale 2D confinement.
Fig. 3: Water under Å-scale 2D confinement.
Fig. 4: Ion transport in the ångström-scale 2D confinement.
Fig. 5: Ion correlation in the ångström-scale 2D confinement.
Fig. 6: Gas properties in 2D confinement.
Fig. 7: Outlook for future research on matter in 2D confinement.

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Acknowledgements

X.C.Z. acknowledges support from the Hong Kong Global STEM Professorship Scheme and the Research Grants Council of Hong Kong (GRF Grant No. 11204123 and No. 11302225). W.Z. acknowledges the support from the Research Grants Council of Hong Kong (GRF CityU11310123 and CRF C1018-23G). M.W. acknowledges the support of the Global Research Assistant Professor Scheme of the CityUHK. J.J. acknowledges the funding support of the National Natural Science Foundation of China (Grant No. 22303072).

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Author notes

  1. These authors contributed equally: Mingzhan Wang, Jian Jiang.

Authors and Affiliations

  1. Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong, China

    Mingzhan Wang  (王铭展), Jian Jiang  (江健), Changxiong Huang  (黄昌雄), Wenjun Zhang  (张文军) & Xiao Cheng Zeng  (曾晓成)

  2. Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong, China

    Mingzhan Wang  (王铭展) & Wenjun Zhang  (张文军)

  3. College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China

    Jian Jiang  (江健)

  4. Shenzhen Research Institute, City University of Hong Kong, Shenzhen, China

    Jian Jiang  (江健)

  5. Hong Kong Institute for Clean Energy, City University of Hong Kong, Hong Kong, China

    Xiao Cheng Zeng  (曾晓成)

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  1. Mingzhan Wang  (王铭展)
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Contributions

M.W. and J.J. wrote the draft of the manuscript with input from all authors. C.H. contributed to the figure presentations. W.Z. and X.C.Z. supervised the project.

Corresponding authors

Correspondence to Wenjun Zhang  (张文军) or Xiao Cheng Zeng  (曾晓成).

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Wang, M., Jiang, J., Huang, C. et al. Matter in ångström-scale two-dimensional confinement. Nat Rev Chem (2026). https://doi.org/10.1038/s41570-026-00805-y

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