Review Article | Published:

Controlling upconversion nanocrystals for emerging applications

Nature Nanotechnology volume 10, pages 924936 (2015) | Download Citation

Abstract

Lanthanide-doped upconversion nanocrystals enable anti-Stokes emission with pump intensities several orders of magnitude lower than required by conventional nonlinear optical techniques. Their exceptional properties, namely large anti-Stokes shifts, sharp emission spectra and long excited-state lifetimes, have led to a diversity of applications. Here, we review upconversion nanocrystals from the perspective of fundamental concepts and examine the technical challenges in relation to emission colour tuning and luminescence enhancement. In particular, we highlight the advances in functionalization strategies that enable the broad utility of upconversion nanocrystals for multimodal imaging, cancer therapy, volumetric displays and photonics.

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Acknowledgements

The authors would like to acknowledge support through the Agency for Science, Technology and Research (A*STAR) (grant nos 122-PSE-0014 and 1231AFG028), the National Research Foundation and the Economic Development Board (Singapore-Peking-Oxford Research Enterprise), the National Natural Science Foundation of China (grant no. R-2014-S-009) through the NUS Research Institute at Suzhou, and the Australian Research Council (Centre of Excellence for Nanoscale BioPhotonics, grant no. CE140100003, and Future Fellowship, grant no. FT 130100517).

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Affiliations

  1. Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, 117602 Singapore, Singapore

    • Bo Zhou
    •  & Xiaogang Liu
  2. Advanced Cytometry Labs, ARC Centre of Excellence for Nanoscale BioPhotonics, Macquarie University, Sydney, New South Wales 2109, Australia

    • Bingyang Shi
    •  & Dayong Jin
  3. Institute for Biomedical Materials and Devices, Faculty of Science, University of Technology Sydney, New South Wales 2007, Australia

    • Dayong Jin
  4. Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543 Singapore, Singapore

    • Xiaogang Liu
  5. Centre for Functional Materials, NUS (Suzhou) Research Institute, Suzhou, Jiangsu 215123, China

    • Xiaogang Liu

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The authors declare no competing financial interests.

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Correspondence to Dayong Jin or Xiaogang Liu.

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https://doi.org/10.1038/nnano.2015.251

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