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High efficiency and stability of ink-jet printed quantum dot light emitting diodes.

ABSTRACT: The low efficiency and fast degradation of devices from ink-jet printing process hinders the application of quantum dot light emitting diodes on next generation displays. Passivating the trap states caused by both anion and cation under-coordinated sites on the quantum dot surface with proper ligands for ink-jet printing processing reminds a problem. Here we show, by adapting the idea of dual ionic passivation of quantum dots, ink-jet printed quantum dot light emitting diodes with an external quantum efficiency over 16% and half lifetime of more than 1,721,000?hours were reported for the first time. The liquid phase exchange of ligands fulfills the requirements of ink-jet printing processing for possible mass production. And the performance from ink-jet printed quantum dot light emitting diodes truly opens the gate of quantum dot light emitting diode application for industry.

SUBMITTER: Xiang C

PROVIDER: S-EPMC7118149 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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High efficiency and stability of ink-jet printed quantum dot light emitting diodes.

Xiang Chaoyu C Wu Longjia L Lu Zizhe Z Li Menglin M Wen Yanwei Y Yang Yixing Y Liu Wenyong W Zhang Ting T Cao Weiran W Tsang Sai-Wing SW Shan Bin B Yan Xiaolin X Qian Lei L

Nature communications 20200402 1

The low efficiency and fast degradation of devices from ink-jet printing process hinders the application of quantum dot light emitting diodes on next generation displays. Passivating the trap states caused by both anion and cation under-coordinated sites on the quantum dot surface with proper ligands for ink-jet printing processing reminds a problem. Here we show, by adapting the idea of dual ionic passivation of quantum dots, ink-jet printed quantum dot light emitting diodes with an external qu ...[more]

PMID: 32242016

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