Quenching-enhanced shift of recombination zone in phosphorescent organic light-emitting diodes

被引：23

作者：

Zhong, G. Y. ^{[1
]}

Zhang, Y. Q. ^{[1
]}

Cao, X. A. ^{[1
]}

机构：

[1] W Virginia Univ, Dept Comp Sci & Elect Engn, Morgantown, WV 26506 USA

来源：

ORGANIC ELECTRONICS | 2010年 / 11卷 / 08期

关键词：

Organic light-emitting diode; Concentration quenching; Recombination zone; Forster energy transfer; EFFICIENT; DEVICES; FLUORESCENT; MOLECULES;

D O I：

10.1016/j.orgel.2010.05.010

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We studied the influence of concentration quenching on exciton distribution and recombination in organic light-emitting diodes (OLEDs) with a neat fac-tris(2-phenylpyridinato-N, C2') iridium (III) [Ir(ppy)(3)] emitting layer (EML). It has been found that electron overflow to the hole transport layer (HTL) at elevated currents was enhanced by quenching in the EML, leading to a broadened recombination zone. The maximum quenching of green phosphorescence occurred in OLEDs with 4 nm Ir(ppy)(3) and correlated well with the strongest blue fluorescence from the HTL. The OLEDs emitted white light with an efficiency of 6.5 cd/A and a quantum efficiency twice as high as compared to similar OLEDs with an additional 4,4',4 '',-tris(N-carbazolyl) triphenylamine (TCTA) EBL. (C) 2010 Elsevier B.V. All rights reserved.

引用

页码：1338 / 1343

页数：6

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