Efficient light emitting diodes from polyfluorene copolymer blends

2005-04-30
Çırpan, Ali
Karasz, FE
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.
SYNTHETIC METALS

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Citation Formats
A. Çırpan and F. Karasz, “Efficient light emitting diodes from polyfluorene copolymer blends,” SYNTHETIC METALS, pp. 195–198, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35908.