Science China Materials

, Volume 59, Issue 6, pp 421–426 | Cite as

Highly efficient inverted organic light-emitting diodes based on thermally activated delayed fluorescence

  • Xiaopeng Lv (吕孝鹏)
  • Hui Wang (王会)
  • Lingqiang Meng (孟令强)
  • Xiaofang Wei (魏晓芳)
  • Yongzhen Chen (陈永振)
  • Xiangbin Kong (孔祥彬)
  • Jianjun Liu (刘建君)
  • Jianxin Tang (唐建新)
  • Pengfei Wang (汪鹏飞)
  • Ying Wang (王鹰)
Letter

Abstract

Green inverted organic light-emitting diodes (OLEDs) based on a thermally activated delayed fluorescent (TADF) emitter, 2-pheyl-4'-carbazole-9-H-thioxanthen-9-one-10,10-dioxide, with a cathode of indium tin oxide (ITO)/ZnO injecting electrons efficiently into the electron transporting layer of Alq3, are demonstrated for the first time. The insertion of 7-nm Cs2CO3 can further enhance the electron injection. The optimized device with 25-nm ZnO and 7-nm Cs2CO3 affords the highest performance of the inverted devices with a current efficiency of 28.1 cd A−1, a power efficiency of 16.1 lm W−1, and an external quantum efficiency of 9.8%. The inverted OLEDs based on TADF emitters are competitive compared with conventional OLEDs because of their air-stable electrodes and TADF emitters, which enable simpler encapsulation.

Keywords

OLEDs thermally activated delayed fluorescence inverted OLEDs 

基于热激活延迟荧光材料的高效倒向有机发光二极管

摘要

本论文首次报道了基于热激活延迟荧光材料TXO-PhCz的倒置结构绿光有机电致发光器件. 器件以ITO/ZnO作为电子注入阴极, 提 高了电子向Alq3层中的有效注入. 7 nm 的Cs2CO3可以进一步提高电子的注入效率. 最优化器件以25-nm ZnO和7-nm Cs2CO3层实现了电子 的有效注入, 器件显示出最佳性能, 器件的电流效率为28.1 cd A−1, 功率为16.1 lmW−1, 外量子效率达9.8%. 基于TADF发光材料的倒向OLEDs 器件由于其电极材料和发光材料的优异稳定性, 可以实现简单封装, 有望替代传统OLEDs.

Supplementary material

40843_2016_5071_MOESM1_ESM.pdf (169 kb)
Supplementary material, approximately 170 KB.

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Copyright information

© Science China Press and Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Xiaopeng Lv (吕孝鹏)
    • 1
    • 2
  • Hui Wang (王会)
    • 3
  • Lingqiang Meng (孟令强)
    • 2
  • Xiaofang Wei (魏晓芳)
    • 2
  • Yongzhen Chen (陈永振)
    • 2
  • Xiangbin Kong (孔祥彬)
    • 2
  • Jianjun Liu (刘建君)
    • 2
  • Jianxin Tang (唐建新)
    • 1
  • Pengfei Wang (汪鹏飞)
    • 2
  • Ying Wang (王鹰)
    • 2
  1. 1.Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow UniversitySuzhouChina
  2. 2.Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingChina
  3. 3.Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry & Materials ScienceNorthwest UniversityXi’anChina

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