Spectral Characteristics of White Organic Light-Emitting Devices Based on Phosphorescent System of Three Iridium Chelates
LIU Sheng-qiang1, YU Jun-sheng1*, ZENG Yan-bo1, ZHAO Juan1, DU Chun-lei2
1. State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054, China 2.Chengdu Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209, China
Abstract：A white organic light-emitting device (WOLED) with a yellow phosphorescence material, bis[2-(4-tertbutylphenyl)benzothiazolato-N,C2’] iridium (acetylacetonate) [(t-bt)2Ir(acac)], and two blue phosphorescence materials, iridium(Ⅲ) bis(4’,6’-difluorophenylpyridinato)tetrakis(1-pyrazolyl)borate (FIr6) and bis[(4,6-difluorophenyl)-pyridinato-N,C2’](picolinate) iridium (Ⅲ) (FIrpic), were fabricated. Stable white emission was realized by using undoped ultrathin yellow emissive layer (EML), two doped blue EMLs together with the proper thickness of an interlayer confining the exciton. The WOLED performed pure white light emission with the Commissions Internationale de l’Eclairage (CIE) coordinates of (0.29±0.01, 0.34±0.01) from 6 to 14 V. Moreover, electroluminescence (EL) characteristics of the devices were also studied to verify the emissive mechanism from a phosphorescent system consisting of three iridium chelates. Also, the results showed that the triple-phosphor-element EMLs WOLED had lower efficiency roll-off owing to the stable recombination zone.
Key words：Organic light-emitting device (OLED);White light;Iridium chelate;Spectral characteristics;A phosphorescence system consisting of three iridium chelates
刘胜强1，于军胜1*，曾彦博1，赵 娟1，杜春雷2 . 三元铱配合物磷光体系的白光有机电致发光器件光谱特性研究 [J]. 光谱学与光谱分析, 2013, 33(03): 636-641.
LIU Sheng-qiang1, YU Jun-sheng1*, ZENG Yan-bo1, ZHAO Juan1, DU Chun-lei2 . Spectral Characteristics of White Organic Light-Emitting Devices Based on Phosphorescent System of Three Iridium Chelates . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2013, 33(03): 636-641.
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