无间隔层结构的高效率荧光/磷光混合型白光有机发光二极管

doi:10.11944/j.issn.1000-0518.2015.10.150186

摘要/Abstract

摘要：

采用磷光红光/荧光蓝光/磷光绿光无间隔层三发光层结构,制备出了高效率荧光/磷光混合型白光有机发光二极管(OLEDs),其中选取具有高荧光量子产率(PLQY)的荧光染料4P-NPD(双[N-(1-萘基)-N-苯基-氨基]四联苯)作为蓝光发射分子,以及常用的高效磷光染料Ir(MDQ)₂(acac)和Ir(ppy)₃(acac)分别作为红光和绿光的客体,通过混合和掺杂的方法制备了相应的发光层,实现了发光层中激子的有效利用和白光发射。制备的白光器件最大电流效率和功率效率分别达到了27.1 cd/A和30.3 lm/W,当电压为6 V时,CIE色坐标为(0.33,0.41),显色指数CRI为70,色温CCT为5432 K。在此基础上,设计制备了高色温的荧光/磷光混合型白光OLEDs,其色温(CCT)达到了7106 K。

关键词: 间隔层, 荧光/磷光混合, 白光有机发光二极管

Abstract:

In this paper, we fabricated high efficiency fluorescen/phosphorescent hybrid white organic light-emitting diodes with phosphorescent red, fluorescent blue and phosphorescent green three emitters without spacer. We used bis[N-(1-napthyl)-N-phenyl-amino] tetraphenyl(4P-NPD) as the fluorescent blue emitter due to its high fluorescence quantum yield(PLQY), the commonly used Ir(MDQ)₂(acac)[MDQ:2-methyl-dibenzo[f,h]quinoxaline, acac:acetylacetonate] and Ir(ppy)₃(acac)[ppy:2-phenylpyridine] were selected as the phosphorescent red and green dopants, respectively. We fabricated the corresponding emitting-layers by blending and doping methods to realize the highly efficient utilization in emitting layers and white light emission. The max current efficiency and power efficiency reach 27.1 cd/A and 30.3 lm/W, respectively. At the driving voltage of 6 V, the device can give off white light with the Commission Internationale de L'Eclairage(CIE)(0.33,0.41), Colour rendering index(CRI) of 70 and Correlated colour temperature(CCT) of 5432 K. On the basis of above structure, we also fabricated hybrid white organic light-emitting diodes with high CCT, which reaches 7106 K.

Key words: spacer, fluorescent/phosphorescent hybrid, white organic light-emitting diodes

代岩峰,张智强,刘一鹏,马东阁. 无间隔层结构的高效率荧光/磷光混合型白光有机发光二极管[J]. 应用化学, 2015, 32(10): 1139-1145.

DAI Yanfeng,ZHANG Zhiqiang,LIU Yipeng,MA Dongge. High Efficiency Fluorescent/Phosphorescent Hybrid White Organic Light-Emitting Diodes Without Spacer Structure[J]. Chinese Journal of Applied Chemistry, 2015, 32(10): 1139-1145.

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