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Dual-Facets Emissive Quantum-Dot Light-Emitting Diode Based on AZO Electrode.

ABSTRACT: We report on a green, dual emissive quantum-dot light-emitting diode (QLED) using alumina (Al)-doped ZnO (AZO) to adjust the band offset between the cathode and QD-emitting layers. The dual emissive QLED structure was designed by enhancing the efficient hole injection/transfer and slowing down the electron injection/transfer from AZO to the QD. The QLEDs presented a maximum luminance of 9450 cd/m2, corresponding to a power efficiency of 15.7 lm/W, a current efficiency of 25.5 cd/A, as well as a turn-on voltage of 2.3 V. It is worth noting that the performance of the dual emissive QLED is comparable to that of a single emissive QLED. Therefore, there is a 1.3-fold enhancement in the performance of the QLED based on the AZO cathode due to the balanced charge injection/transfer.

SUBMITTER: Chen J

PROVIDER: S-EPMC8836426 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Dual-Facets Emissive Quantum-Dot Light-Emitting Diode Based on AZO Electrode.

Chen Jing J Huang Qianqian Q Lei Wei W

Materials (Basel, Switzerland) 20220119 3

We report on a green, dual emissive quantum-dot light-emitting diode (QLED) using alumina (Al)-doped ZnO (AZO) to adjust the band offset between the cathode and QD-emitting layers. The dual emissive QLED structure was designed by enhancing the efficient hole injection/transfer and slowing down the electron injection/transfer from AZO to the QD. The QLEDs presented a maximum luminance of 9450 cd/m<sup>2</sup>, corresponding to a power efficiency of 15.7 lm/W, a current efficiency of 25.5 cd/A, as ...[more]

PMID: 35160686

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