High-efficiency/CRI/color stability warm white organic light-emitting diodes by incorporating ultrathin phosphorescence layers in a blue fluorescence layer
Miao Yanqin,
Wang Kexiang,
Zhao Bo,
Gao Long,
Tao Peng,
Liu Xuguang,
Hao Yuying,
Wang Hua,
Xu Bingshe,
Zhu Furong
Affiliations
Miao Yanqin
Key Laboratory of Interface Science and Engineering in Advanced Materials of the Ministry of Education, Research Center of Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan 030024, P.R. China
Wang Kexiang
Key Laboratory of Interface Science and Engineering in Advanced Materials of the Ministry of Education, Research Center of Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan 030024, P.R. China
Zhao Bo
Key Laboratory of Interface Science and Engineering in Advanced Materials of the Ministry of Education, Research Center of Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan 030024, P.R. China
Gao Long
Key Laboratory of Interface Science and Engineering in Advanced Materials of the Ministry of Education, Research Center of Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan 030024, P.R. China
Tao Peng
Key Laboratory of Interface Science and Engineering in Advanced Materials of the Ministry of Education, Research Center of Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan 030024, P.R. China
Liu Xuguang
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, P.R. China
Hao Yuying
Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education, College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024, P.R. China
Wang Hua
Key Laboratory of Interface Science and Engineering in Advanced Materials of the Ministry of Education, Research Center of Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan 030024, P.R. China
Xu Bingshe
Key Laboratory of Interface Science and Engineering in Advanced Materials of the Ministry of Education, Research Center of Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan 030024, P.R. China
Zhu Furong
Department of Physics, Institute of Advanced Materials, and Institute of Research and Continuing Education (Shenzhen), Hong Kong Baptist University, Kowloon Tong, NT, Hong Kong, P.R. China
By incorporating ultrathin (80, low correlated color temperature of <3600 K, and high color stability at a wide voltage range of 5 V–9 V. These hybrid WOLEDs also reveal high forward-viewing external quantum efficiencies (EQE) of 17.82%–19.34%, which are close to the theoretical value of 20%, indicating an almost complete exciton harvesting. In addition, the electroluminescence spectra of the hybrid WOLEDs can be easily improved by only changing the incorporating sequence of the ultrathin phosphorescence layers without device efficiency loss. For example, the hybrid WOLED with an incorporation sequence of ultrathin red/yellow/green phosphorescence layers exhibits an ultra-high CRI of 96 and a high EQE of 19.34%. To the best of our knowledge, this is the first WOLED with good tradeoff among device efficiency, CRI, and color stability. The introduction of ultrathin (<0.1 nm) phosphorescence layers can also greatly reduce the consumption of phosphorescent emitters as well as simplify device structures and fabrication process, thus leading to low cost. Such a finding is very meaningful for the potential commercialization of hybrid WOLEDs.
