Rational arrangement of multiple exciplex hosts for highly efficient white organic light-emitting diodes. Issue 40 (4th October 2021)

• Record Type: Journal Article
• Authors: Sun, Shuang-Qiao; Liu, Han; Feng, Dan-Dan; Huang, Chen-Chao; Wang, Tong-Tong; He, Wei; Zhang, Yi-Jie; Luo, Wei; Sun, Qi; Fung, Man-Keung
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 40(2021)
• Page Start: 14327
• Page End: 14333
• Publication Date: 2021-10-04
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1tc02934g
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : Designing a novel exciplex host and arranging rational multiple-exciplex hosts in emissive layers.Two and three color WOLEDs based on multiple exciplex hosts exhibited maximum EQEs of 30.9% and 27.0%, respectively. Remarkedly, their EQEs remained at 22.1% and 21.3% at a high luminance of 5000 cd m −2 . Abstract : Energy matching between the triplet level of the exciplex hosts and phosphorescent emitters is of particular importance to achieve highly efficient exciplex-based white organic light emitting diodes (WOLEDs). Herein, we design a novel exciplex host and use it for WOLEDs by arranging rational multiple-exciplex hosts in emissive layers. The resulting two-color warm WOLED, by doping blue and orange phosphorescent emitters, shows a maximum forward-viewing power efficiency and external quantum efficiency (EQE) of 104.6 lm W −1 and 30.9%, respectively. Significantly, the EQE still remains 22.1% at 5000 cd m −2 . Meanwhile, the three-color warm WOLED has a high color rendering index of over 80 with a maximum EQE of 27.0% and the EQE can remain 21.3% at 5000 cd m −2 . These results indicate that rational arrangement of multiple-exciplex hosts in emissive layers is promising for the fabrication of highly efficient WOLEDs.