›› 2015, Vol. 24 ›› Issue (2): 24222-024222.doi: 10.1088/1674-1056/24/2/024222

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Exciplex formation and electroluminescent absorption in ultraviolet organic light-emitting diodes

张琪a, 张浩a, 张小文b, 徐韬a, 魏斌a   

  1. a School of Materials Science and Engineering & Key Laboratory of Advanced Display and System Applications, Ministry of Education, Shanghai University, Shanghai 200072, China;
    b Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004, China
  • 收稿日期:2014-06-02 修回日期:2014-07-14 出版日期:2015-02-05 发布日期:2015-02-05
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61136003 and 61275041) and the Guangxi Provincial Natural Science Foundation, China (Grant No. 2012GXNSFBA053168).

Exciplex formation and electroluminescent absorption in ultraviolet organic light-emitting diodes

Zhang Qi (张琪)a, Zhang Hao (张浩)a, Zhang Xiao-Wen (张小文)b, Xu Tao (徐韬)a, Wei Bin (魏斌)a   

  1. a School of Materials Science and Engineering & Key Laboratory of Advanced Display and System Applications, Ministry of Education, Shanghai University, Shanghai 200072, China;
    b Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004, China
  • Received:2014-06-02 Revised:2014-07-14 Online:2015-02-05 Published:2015-02-05
  • Contact: Zhang Xiao-Wen, Wei Bin E-mail:zhang-xiaowen@163.com;bwei@shu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61136003 and 61275041) and the Guangxi Provincial Natural Science Foundation, China (Grant No. 2012GXNSFBA053168).

摘要: We investigated the formation of exciplex and electroluminescent absorption in ultraviolet organic light-emitting diodes (UV OLEDs) using different heterojunction structures. It is found that an energy barrier of over 0.3 eV between the emissive layer (EML) and adjacent transport layer facilitates exciplex formation. The electron blocking layer effectively confines electrons in the EML, which contributes to pure UV emission and enhances efficiency. The change in EML thickness generates tunable UV emission from 376 nm to 406 nm. In addition, the UV emission excites low-energy organic function layers and produces photoluminescent emission. In UV OLED, avoiding the exciplex formation and averting light absorption can effectively improve the purity and efficiency. A maximum external quantum efficiency of 1.2% with a UV emission peak of 376 nm is realized.

关键词: exciplex, tunable UV emission, electroluminescent absorption

Abstract: We investigated the formation of exciplex and electroluminescent absorption in ultraviolet organic light-emitting diodes (UV OLEDs) using different heterojunction structures. It is found that an energy barrier of over 0.3 eV between the emissive layer (EML) and adjacent transport layer facilitates exciplex formation. The electron blocking layer effectively confines electrons in the EML, which contributes to pure UV emission and enhances efficiency. The change in EML thickness generates tunable UV emission from 376 nm to 406 nm. In addition, the UV emission excites low-energy organic function layers and produces photoluminescent emission. In UV OLED, avoiding the exciplex formation and averting light absorption can effectively improve the purity and efficiency. A maximum external quantum efficiency of 1.2% with a UV emission peak of 376 nm is realized.

Key words: exciplex, tunable UV emission, electroluminescent absorption

中图分类号:  (Other nonlinear optical materials; photorefractive and semiconductor materials)

  • 42.70.Nq
42.25.Gy (Edge and boundary effects; reflection and refraction) 42.25.Bs (Wave propagation, transmission and absorption)