Superior Efficiency and Low-Efficiency Roll-Off White Organic Light-Emitting Diodes Based on Multiple Exciplexes as Hosts Matched to Phosphor Emitters

被引：21

作者：

Ying, Shian ^{[1
]}

Pang, Peiyuan ^{[1
]}

Zhang, Shuai ^{[1
]}

Sun, Qian ^{[1
]}

Dai, Yanfeng ^{[1
]}

Qiao, Xianfeng ^{[1
]}

Yang, Dezhi ^{[1
]}

Chen, Jiangshan ^{[1
]}

Ma, Dongge ^{[1
]}

机构：

[1] South China Univ Technol, State Key Lab Luminescent Mat & Devices, Inst Polymer Optoelect Mat & Devices, Ctr Aggregat Induced Emiss, Guangzhou 510640, Guangdong, Peoples R China

来源：

ACS APPLIED MATERIALS & INTERFACES | 2019年 / 11卷 / 34期

基金：

中国国家自然科学基金;

关键词：

exciplex; phosphorescent host; low efficiency roll-off; white organic light-emitting diodes; energy transfer; EXTERNAL QUANTUM EFFICIENCY; HIGH-PERFORMANCE OLEDS; TRIPLET EXCITONS; EMISSIVE-LAYER; BIPOLAR HOST; DEVICES; STABILITY; SINGLET;

D O I：

10.1021/acsami.9b09429

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Based on exciplexes as hosts, the monochromatic organic light-emitting diodes (OLEDs) have achieved high power and external quantum efficiencies. However, the high-quality white OLEDs (WOLEDs) with high color rendering index (CRI) have the unsatisfactory efficiencies at high luminance, particularly in terms of power efficiency (PE), resulting in high energy consumption. Here, a new design concept using multiple exciplexes as hosts to match different phosphors has been demonstrated to develop high-performance WOLEDs. It can be seen that the resulting WOLEDs work at a low turn-on voltage of 2.3 V and exhibit the large forward-viewing PE and external quantum efficiency (EQE) of 79 lm W-1 and 22.5%, respectively, without light out-coupling techniques. Significantly, the PE and EQE still remain 48.0 lm W-1 and 21.4% at 1000 cd m(-2), showing extremely low efficiency roll-off. The CRI is as high as 81 . The keys to success are the selection of the different exciplex hosts matched to different phosphors and the reasonable arrangement of emissive layers, which are beneficial to regulate the exciton distribution and reduce the energy losses.

引用

页码：31078 / 31086

页数：9