Efficient light emitting diodes from polyfluorene copolymer blends

被引:20
作者
Cirpan, A [1 ]
Ding, LM [1 ]
Karasz, FE [1 ]
机构
[1] Univ Massachusetts, Dept Polymer Sci & Engn, Amherst, MA 01003 USA
关键词
light emitting diode; electroluminescence; polyfluorene; blending;
D O I
10.1016/j.synthmet.2005.02.003
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Highly efficient light emitting diodes were obtained by blending blue-emitting poly [(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(N,N'-diphenyl)-N,N-di(p-butyl-oxyphenyl)-1 ,4-diaminobenzene] (1) with green-emitting poly [(9,9-dioctyl-2,7-divinylene-fluorenylene)-alt-co-{2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene}] (II). Only green emission was obtained from the films of polymer blends and from corresponding double-layer LEDs, indicating an almost complete Forster energy transfer from I to II. These devices show enhanced external quantum efficiency, higher brightness and lowor turn on voltages. Luminance and efficiency of 2.6 x 10(4) cd/m(2) and 2.55%, respectively, were obtained. (c) 2005 Elsevier B.V. All rights reserved.
引用
收藏
页码:195 / 198
页数:4
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