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Nanoscale correlation of single-molecule reactivity and charge carrier dynamics in a two-dimensional layered InSe photocatalyst

Nature Catalysis volume 9, pages 87–94 (2026)Cite this article

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Abstract

Photogenerated charge carriers play a pivotal role in driving chemical transformations during photocatalysis. However, the structural complexity of photocatalysts presents challenges in establishing nanoscale correlation between carrier dynamics and photocatalytic activity. Here we integrate single-molecule fluorescence imaging with femtosecond interferometric scattering microscopy to resolve the carrier dynamics and specific reaction rate of hydroxyl radical oxidation at the individual structural features (that is, basal plane, edge and wrinkle) in 2D layered indium selenide (InSe). We find a positive linear correlation between the specific reaction rate and the carrier lifetime, but only a weak correlation with the carrier concentration. Moreover, both basal planes and edges exhibit peak lifetimes and specific reaction rates in three-layer InSe. These spatially resolved, correlative single-molecule superlocalization and ultrafast measurements are a powerful tool for investigations of structure–function correlation.

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Fig. 1: Femto-iSCAT and SMFI characterizations of photocatalysis.
Fig. 2: Femto-iSCAT and SMFI for the characterization of carrier dynamics and specific reaction rates at the same InSe flake.
Fig. 3: The correlation between carrier dynamics and specific reaction rate.
Fig. 4: Layer-dependent photocatalytic activities and carrier dynamics at different structural features of 2D layered InSe.

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Data that support the findings of this study are available within the Article and its Supplementary Information. Additional data are available from the authors upon reasonable request. Source data are provided with this paper.

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Acknowledgements

This work was financially supported by the National Key R&D Program of China (grant numbers 2024YFA1210801 and 2023YFA1509001), the Natural Science Foundation of Xiamen, China (grant number 3502Z202471023), the National Natural Science Foundation of China (NSFC) (grant numbers 32230063 and 22574138), the Fundamental Research Funds for the Central Universities (grant number 20720250040), the Scientific Research Foundation of State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory (grant number 2024XAKJ0100005) and Technologies of Energy Materials of Fujian Province (IKKEM) (grant number RD2020050501).

Author information

Author notes

  1. These authors contributed equally: Li-Wen Wu, Pin-Tian Lyu, Ran Zhang, Keng Chen.

Authors and Affiliations

  1. State Key Laboratory of Physical Chemistry of Solid Surfaces, MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China

    Li-Wen Wu, Ran Zhang, Keng Chen, Li Zuo, Dongliang Song, Zhen-Zhen Feng, Ya-Ting Nie, Teng-Xiang Huang & Ning Fang

  2. Pen-Tung Sah Institute of Micro-Nano Science and Technology, Xiamen University, Xiamen, China

    Li-Wen Wu, Ran Zhang, Keng Chen, Li Zuo, Dongliang Song, Zhen-Zhen Feng, Ya-Ting Nie, Teng-Xiang Huang & Ning Fang

  3. State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China

    Pin-Tian Lyu & Bin Kang

  4. School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China

    Xiaodong Cheng

  5. Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province, Xiamen, China

    Ning Fang

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Contributions

T.-X.H., B.K. and N.F. conceived the idea, designed the experiments and wrote the manuscript. L.-W.W., P.-T.L., R.Z. and K.C. performed the imaging experiments and data analysis. L.Z., D.S. and X.C. helped with data analysis. Z.-Z.F. and Y.-T.N. helped with the experiments.

Corresponding authors

Correspondence to Teng-Xiang Huang, Bin Kang or Ning Fang.

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Wu, LW., Lyu, PT., Zhang, R. et al. Nanoscale correlation of single-molecule reactivity and charge carrier dynamics in a two-dimensional layered InSe photocatalyst. Nat Catal 9, 87–94 (2026). https://doi.org/10.1038/s41929-025-01472-w

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