A single-heterojunction electrophosphorescence device with high efficiency, long lifetime and suppressive roll-off

被引:14
作者
Li, Yunfei [1 ]
Hao, Yuying [1 ,2 ]
Yan, Zhengfu [1 ]
Liu, Huihui [2 ]
Wang, Hua [2 ]
Xu, Bingshe [2 ]
机构
[1] Taiyuan Univ Technol, Coll Phys & Optoelect, Taiyuan 030024, Peoples R China
[2] Taiyuan Univ Technol, Key Lab Interface Sci & Engn Adv Mat, Taiyuan 030024, Peoples R China
关键词
Electrophosphorescence; Single-heterojunction; Enhanced efficiency; Extended lifetime; Suppressive roll-off; LIGHT-EMITTING DEVICES; TRANSPORT LAYER; EMISSION; DIODES; TIME; FILM;
D O I
10.1016/j.synthmet.2012.11.024
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We have demonstrated an electrophosphorescence organic light emitting device (PHOLED) with single-heterojunction to realize simultaneously high efficiency/long lifetime/suppressive roll-off. Therein, the energy barriers between the abrupt interfaces in the carrier transport path are eliminated and the effective and balanced carrier injection and transport are obtained using appropriate chemical doping of the wide band gap materials as the carrier transport layers. The optimized device realizes a maximum power efficiency of 32.1 lm/W (Current efficiency of 40.9 cd/A), which is about 3.1 times that of the referential multi-heterojunction PHOLED, especially the efficiency roll-off is effectively suppressed at the high current density. Furthermore, the operational lifetime is beyond 15 folds of the reference device. These results suggest a simple and feasible design to achieve extended lifetimes and improved efficiency for PHOLED. (C) 2012 Elsevier B.V. All rights reserved.
引用
收藏
页码:12 / 16
页数:5
相关论文
共 31 条
[1]   Efficient electrophosphorescence using a doped ambipolar conductive molecular organic thin film [J].
Adachi, Chihaya ;
Kwong, Raymond ;
Forrest, Stephen R. .
ORGANIC ELECTRONICS, 2001, 2 (01) :37-43
[2]   Degradation phenomena in small-molecule organic light-emitting devices [J].
Aziz, H ;
Popovic, ZD .
CHEMISTRY OF MATERIALS, 2004, 16 (23) :4522-4532
[3]   Transient analysis of organic electrophosphorescence. II. Transient analysis of triplet-triplet annihilation [J].
Baldo, MA ;
Adachi, C ;
Forrest, SR .
PHYSICAL REVIEW B, 2000, 62 (16) :10967-10977
[4]   Highly efficient phosphorescent emission from organic electroluminescent devices [J].
Baldo, MA ;
O'Brien, DF ;
You, Y ;
Shoustikov, A ;
Sibley, S ;
Thompson, ME ;
Forrest, SR .
NATURE, 1998, 395 (6698) :151-154
[5]   Fuzzy-junction organic light-emitting devices [J].
Chen, CW ;
Cho, TY ;
Wu, CC ;
Yu, HL ;
Luh, TY .
APPLIED PHYSICS LETTERS, 2002, 81 (09) :1570-1572
[6]   Organic light-emitting diodes with a bipolar transport layer [J].
Choong, VE ;
Shi, S ;
Curless, J ;
Shieh, CL ;
Lee, HC ;
So, F ;
Shen, J ;
Yang, J .
APPLIED PHYSICS LETTERS, 1999, 75 (02) :172-174
[7]   Hole mobility of N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl) benzidine investigated by using space-charge-limited currents [J].
Chu, Ta-Ya ;
Song, Ok-Keun .
APPLIED PHYSICS LETTERS, 2007, 90 (20)
[8]   Graded mixed-layer organic light-emitting devices [J].
Chwang, AB ;
Kwong, RC ;
Brown, JJ .
APPLIED PHYSICS LETTERS, 2002, 80 (05) :725-727
[9]   Close-packed hemispherical microlens arrays for light extraction enhancement in organic light-emitting devices [J].
Eom, Sang-Hyun ;
Wrzesniewski, Edward ;
Xue, Jiangeng .
ORGANIC ELECTRONICS, 2011, 12 (03) :472-476
[10]   Highly efficient, single-layer organic light-emitting devices based on a graded-composition emissive layer [J].
Erickson, Nicholas C. ;
Holmes, Russell J. .
APPLIED PHYSICS LETTERS, 2010, 97 (08)