標題: Highly efficient red-electrophosphorescent devices based on polyfluorene copolymers containing charge-transporting pendant units
作者: Wu, FI
Shih, PI
Tseng, YH
Chen, GY
Chien, CH
Shu, CF
Tung, YL
Chi, Y
Jen, AKY
應用化學系
Department of Applied Chemistry
公開日期: 28-七月-2005
摘要: We have systematically examined the photoluminescence (PL) and electroluminescence (EL) behavior of blends comprising two efficient red phosphors doped, respectively, into the blue-emitting polyfluorene derivatives PF-TPA-OXD and PF-OXD. The host polymers, which contain both hole- and electron-transporting or merely electron-tran sporting side chains, are capable of facilitating charge injection and transport. After determining the HOMO and LUMO energy levels of these materials, we were able to match the dopant with its most suitable host to achieve the direct formation and confinement of an exciton at the dopant. This configuration also leads to a reduction in the electrical excitation of the host polymer, which in turn decreases the degree of exciton loss arising from nonradiative decay of the host triplet. Using this approach, we were able to realize the production of high-performance red-electrophosphorescent devices. For Os(fppz)-doped devices, we obtain a balanced charge recombination in conjunction with higher current and luminance when using PF-TPA-OXD as the host matrix; this device reached a maximum external quantum efficiency of 8.37% with a peak brightness of 16 720 cd/m(2). The absence of charge-transporting pendant units, i.e., the device fabricated from poly [9,9-dioctylfluorene-2,7-diyl] (POF), led, however, to relatively poor electroluminescence characteristics (5.81% and 2144 cd/m(2)).
URI: http://dx.doi.org/10.1021/jp051747k
http://hdl.handle.net/11536/13469
ISSN: 1520-6106
DOI: 10.1021/jp051747k
期刊: JOURNAL OF PHYSICAL CHEMISTRY B
Volume: 109
Issue: 29
起始頁: 14000
結束頁: 14005
顯示於類別:期刊論文


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  1. 000230698100023.pdf