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Mechanism study on highly efficient polymer light-emitting diodes utilizing double-layered alkali halide electron injection layer.

ABSTRACT: Enhancing the injection of electron is an effective strategy to improve the performance of polymer light-emitting diodes (PLEDs). In this work, we reported a 286% improvement in current efficiency (CE) of PLEDs by using double-layered alkali halide electron injection layer (EIL) NaCl/LiF instead of LiF. A significant enhancement of electron injection was observed after inserting the NaCl layer. To understand the mechanism of such improvement, the devices with KBr/LiF and CsF/LiF as EILs were also investigated. Experimental results show that metal cation migrated under the effect of built-in electric field (V_bi), which plays the main role on the improvement of electron injection in PLEDs.

SUBMITTER: Niu Q

PROVIDER: S-EPMC6890694 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Mechanism study on highly efficient polymer light-emitting diodes utilizing double-layered alkali halide electron injection layer.

Niu Qiaoli Q Niu Qiaoli Q Tong Jing J Duan Xiaomeng X Zhang Haoran H Wang Dexu D Hai Gang G Lv Hao H Zeng Wenjin W Xia Ruidong R Min Yonggang Y

Scientific reports 20191203 1

Enhancing the injection of electron is an effective strategy to improve the performance of polymer light-emitting diodes (PLEDs). In this work, we reported a 286% improvement in current efficiency (CE) of PLEDs by using double-layered alkali halide electron injection layer (EIL) NaCl/LiF instead of LiF. A significant enhancement of electron injection was observed after inserting the NaCl layer. To understand the mechanism of such improvement, the devices with KBr/LiF and CsF/LiF as EILs were als ...[more]

PMID: 31796835

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