Jan. 2021

Article Contents

Chinese Optics> 2021> 14(1): 117-134.

LYU Mei, ZHANG Li, ZHANG Yan, YUAN Ming-jian. Strategies for improving the stability of quantum dots light-emitting diodes[J]. Chinese Optics, 2021, 14(1): 117-134. doi: 10.37188/CO.2020-0184

Citation:

LYU Mei, ZHANG Li, ZHANG Yan, YUAN Ming-jian. Strategies for improving the stability of quantum dots light-emitting diodes[J].Chinese Optics, 2021, 14(1): 117-134.doi:10.37188/CO.2020-0184

LYU Mei, ZHANG Li, ZHANG Yan, YUAN Ming-jian. Strategies for improving the stability of quantum dots light-emitting diodes[J]. Chinese Optics, 2021, 14(1): 117-134. doi: 10.37188/CO.2020-0184

Citation:

LYU Mei, ZHANG Li, ZHANG Yan, YUAN Ming-jian. Strategies for improving the stability of quantum dots light-emitting diodes[J].Chinese Optics, 2021, 14(1): 117-134.doi:10.37188/CO.2020-0184

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Strategies for improving the stability of quantum dots light-emitting diodes

doi:10.37188/CO.2020-0184

1.
School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
2.
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin 300071, China

Funds:Supported by National Science Foundation of Tianjin (No. 17JCYBJC40900, No. 18YFZCGX00580)

More Information

Corresponding author:yanzhang@sxu.edu.cn;yuanmj@nankai.edu.cn
Received Date:12 Oct 2020
Rev Recd Date:30 Nov 2020

Available Online:14 Jan 2021

Publish Date:25 Jan 2021

Abstract

Abstract

Quantum dot Light-Emitting Diodes (QLEDs) are applied to the lighting and display industry for their unique photoelectric characteristics. Their External Quantum Efficiency (EQEs) is quickly meeting commercial requirements while the device’s lifetime is still one of their biggest challenges. The significant factors affecting the lifetime of QLEDs are divided into two aspects including the stability of the functional layer’s materials and charge imbalance. Various strategies for enhancing QLEDs stability are discussed including improving the stability of quantum dots, implementing Charge Transport Layers (CTLs) and promoting charge balance. With the deepening understanding of the degradation mechanism of QLEDs, more stable quantum dots and QLEDs devices have been developed. However, there are still some obstacles to the commercialization of QLEDs. For example, the high toxicity of Cd and the lifetime and efficiency of blue QLEDs are far lower than the corresponding levels of green and red QLEDs. In addition, the stability of QLEDs at high brightness (1000 cd m ⁻²) is usually much shorter, which still limits the development of QLEDs. Therefore, research and development efforts for QLEDs should be further strengthened to overcome these technical obstacles and achieve the future commercialization of QLEDs.
- quantum dots,
- quantum dots light-emitting diodes,
- lifetime,
- stability,
- charge balance

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References (92)

References

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