Abstract

Quantum dot light-emitting diodes are promising light sources for applications in displays. However, to date, there have been no reports of devices that simultaneously offer both high brightness and high external quantum efficiency. Here, we report red, green and blue quantum dot light-emitting diodes based on CdSe/ZnSe core/shell structures that have these attributes. We demonstrate devices with maximum external quantum efficiencies of 21.6%, 22.9% and 8.05% for red, green and blue colours with corresponding brightness of 13,300 cd m–2, 52,500 cd m–2 and 10,100 cd m–2. The devices also offer peak luminance of 356,000 cd m–2, 614,000 cd m–2 and 62,600 cd m2, respectively. We postulate that this high performance is due to the use of Se throughout the core/shell regions and the existence of alloyed bridging layers at the core/shell interfaces. This study suggests that in the future visible quantum dot light-emitting diodes will also be suitable for lighting applications.

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Acknowledgements

We gratefully acknowledge the financial support from the National Natural Science Foundation of China (grant numbers 61474037, 61874039, 11634011, 61434002, 11722435, 11504357, 11404314 and 21671058), Key Project of National Natural Science Foundation of China (grant number U1604261), National Key Basic Research Programme of China (grant number 2017YFA0303500), and the Natural Science Foundation of Anhui Province (1708085MA06).

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Affiliations

  1. Key Laboratory for Special Functional Materials of Ministry of Education, National & Local Joint Engineering Research Centre for High-efficiency Display and Lighting Technology, School of Materials and Engineering, Collaborative Innovation Centre of Nano Functional Materials and Applications, Henan University, Kaifeng, China

    • Huaibin Shen
    • , Yanbin Zhang
    • , Qingli Lin
    • , Zhaohan Li
    • , Ling Chen
    • , Zaiping Zeng
    • , Yu Jia
    • , Shujie Wang
    • , Zuliang Du
    •  & Lin Song Li
  2. International Centre for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at Microscale, Synergetic Innovation Centre of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, China

    • Qiang Gao
    •  & Zhenyu Zhang
  3. Institute for Advanced Study, Shenzhen University, Shenzhen, China

    • Qiang Gao
    •  & Xiaoguang Li
  4. Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui, China

    • Yue Lin
  5. School of Physics and Engineering, Zhengzhou University, Zhengzhou, China

    • Yu Jia

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Contributions

H.B.S. and Z.Y.Z. conceived the central ideas and concepts. H.B.S., Y.B.Z. and Q.L.L. synthesized the materials, fabricated the devices and collected the performance data of the QLEDs. Q.G., X.L. and Z.Y.Z. developed the equivalent circuit model. H.B.S. and Z.H.L. characterized the non-blinking aspects. Y.L. performed the HAADF-STEM characterizations. L.C. and S.J.W. obtained the SEM data. H.B.S., Q.G. and Z.Y.Z. wrote the manuscript. Z.Y.Z., Z.L.D. and L.S.L. directed the project. All authors discussed the results and assisted in the data interpretation and manuscript preparation.

Competing interests

The authors declare no competing interests.

Corresponding authors

Correspondence to Zuliang Du or Lin Song Li or Zhenyu Zhang.

Supplementary Information

  1. Supplementary Information

    Detailed analysis of the emission properties of the LEDs.

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DOI

https://doi.org/10.1038/s41566-019-0364-z