Add to BibSonomy
Abstract
Highly efficient tandem organic light-emitting diodes (TOLEDs) were achieved based on a non-doped charge generation unit (CGU) consisting of LiF/Al/C60/4,4’,4”-tris(N-3-methylphenyl-N-phenyl-amino) triphenylamine (m-MTDATA) and ultrathin emitting layers. The current–voltage characteristics of the CGU devices and electron-only devices and the capacitance–voltage characteristics of the CGU-based capacitance devices were characterized to explore the charge generation and injection mechanisms. The charge generation process occurs at the interface of C60/m–MTDATA through electron transferring from the highest occupied molecular orbital of m-MTDATA to the lowest unoccupied molecular orbital of C60. It is found that the thinner C60 layer contributes to efficient electron injection. Under the optimal structure, the blue TOLEDs exhibit a maximum current efficiency (${{\rm CE}_{{\max }}}$) of 43.3 cd/A. The ${{\rm CE}_{{\max }}}$ and maximum external quantum efficiency (${{\rm EQE}_{{\max }}}$) of the white TOLEDs reach 84.6 cd/A and 26.7%, respectively.
© 2020 Optical Society of America
Full Article | PDF ArticleMore Like This
Jia-Xiu Man, Shou-Jie He, Chang-Sheng Shi, Han-Nan Yang, Deng-Ke Wang, and Zheng-Hong Lu
Opt. Lett. 45(13) 3561-3564 (2020)
Ye Yu, Chen Cao, Zhijun Wu, Qihui Wu, Wenyan Lin, Xuekang Peng, Yu Jin, Xining Zhang, Huishan Yang, and Qingxiao Tong
Opt. Lett. 44(4) 931-934 (2019)
Lishuang Wu, Yaoyao Yu, Haichao Liu, Huishan Yang, Wenyan Lin, Zhijun Wu, and Bing Yang
Opt. Express 26(26) A996-A1006 (2018)