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Highly stable QLEDs with improved hole injection via quantum dot structure tailoring.

ABSTRACT: For the state-of-the-art quantum dot light-emitting diodes, while the ZnO nanoparticle layers can provide effective electron injections into quantum dots layers, the hole transporting materials usually cannot guarantee sufficient hole injection owing to the deep valence band of quantum dots. Developing proper hole transporting materials to match energy levels with quantum dots remains a great challenge to further improve the device efficiency and operation lifetime. Here we demonstrate high-performance quantum dot light-emitting diodes with much extended operation lifetime using quantum dots with tailored energy band structures that are favorable for hole injections. These devices show a T₉₅ operation lifetime of more than 2300?h with an initial brightness of 1000?cd?m^-2, and an equivalent T₅₀ lifetime at 100?cd?m^-2 of more than 2,200,000?h, which meets the industrial requirement for display applications.

SUBMITTER: Cao W

PROVIDER: S-EPMC6031613 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Highly stable QLEDs with improved hole injection via quantum dot structure tailoring.

Cao Weiran W Xiang Chaoyu C Yang Yixing Y Chen Qi Q Chen Liwei L Yan Xiaolin X Qian Lei L

Nature communications 20180704 1

For the state-of-the-art quantum dot light-emitting diodes, while the ZnO nanoparticle layers can provide effective electron injections into quantum dots layers, the hole transporting materials usually cannot guarantee sufficient hole injection owing to the deep valence band of quantum dots. Developing proper hole transporting materials to match energy levels with quantum dots remains a great challenge to further improve the device efficiency and operation lifetime. Here we demonstrate high-perf ...[more]

PMID: 29973590

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