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951.
Liang Liao Yi Pang Liming Ding Frank E. Karasz Philip R. Smith Michael A. Meador 《Journal of polymer science. Part A, Polymer chemistry》2004,42(23):5853-5862
Soluble yellow/orange‐emitting poly[tris(2,5‐dihexyloxy‐1,4‐phenylenevinylene)‐alt‐(1,3‐phenylenevinylene)] derivatives ( 6 ) were synthesized and characterized. These polymers contained oligo(p‐phenylene vinylene) chromophores of equal conjugation length, which were jointed via a common m‐phenylene unit. An optical comparison of 6 and its model compound ( 8 ) at room temperature and low temperatures revealed the similarity in their absorption and fluorescence band structures. The vibronic band structure of 6 was assigned with the aid of the spectroscopic data for 8 at the low temperatures. 6 was electroluminescent and had an emission maximum wavelength at approximately 565 nm. With the device indium tin oxide/PEDOT/ 6 /Ca configuration, the polymer exhibited an external quantum efficiency as high as 0.25%. Simple substitution on m‐phenylene of 6 raised the electroluminescence output by a factor of about 10. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5853–5862, 2004 相似文献
952.
沉积亚单层荧光染料提高有机发光器件的发光效率 总被引:2,自引:1,他引:1
结合掺杂薄层作为发光探针层的方法和亚单层(sub-monolayer)有机发光技术,利用沉积在有机发光器件发光层中的亚单层奎丫啶酮(Quinacridone,QAD)分子作为探针,同时改变QAD层的位置,对有机发光器件中激子的形成与扩散进行了研究,器件结构为ITO/NPB(60 nm)/ Alq3(x nm)/QAD(0.05 nm)/Alq3[(60-x) nm]/LiF/Al(其中x=0,2.5,5,7.5 nm).通过对各器件不同条件下的电致发光谱、发光强度和发光效率的对比研究,得到在x=5 nm处引入亚单层QAD可以使QAD分子通过能量转移而获得的激子数量最多,进而可以实现高效率的发光. 相似文献
953.
High extraction efficiency,laterally injected,light emitting diodes combining microcavities and photonic crystals 总被引:1,自引:0,他引:1
Rattier Maxime Krauss Thomas F. Carlin Jean-François Stanley Ross Oesterle Ursula Houdré Romuald Smith Christopher J.M. De La Rue Richard M. Benisty Henri Weisbuch Claude 《Optical and Quantum Electronics》2002,34(1-3):79-89
The use of photonic crystals (PCs) for realistic light emitting diodes (LEDs) is discussed, given the constraints of planar semiconductor technology. A viable route for the fabrication of high-efficiency high-brightness electrically injected LEDs is presented. The starting point is a top-emitting microcavity using a single Alox Bragg mirror. The active area is surrounded by two-dimensional PCs, namely arrays of air rods etched through the top layers; injection of the electrons is achieved through the crystals. Design rules for PCs as efficient out-couplers are detailed. The building blocks are assessed experimentally, and we show that promising results are at hand. 相似文献
954.
With the aim of endowing triplet emitters in the development of organic light-emitting devices (OLEDs) with electron-injection/-transporting (EI/ET) features, the phenylsulfonyl moiety was introduced into the phenyl ring of a 2-phenylpyridine (Hppy) ligand and the yellow phosphorescent heteroleptic iridium(III) complex 1 was developed. It was shown that the SO(2)Ph unit could provide EI/ET character to 1, as indicated from both electrochemical and computational data. Complex 1 is a promising yellow-emitting material for both monochromatic OLEDs and white OLEDs (WOLEDs). The outstanding electronic traits associated with 1, coupled with careful device design, afforded very attractive electroluminescent performances for two-element WOLEDs, including a low turn-on voltage of less than 3.7 V, a maximum brightness of 48,000 cd m(-2), an external quantum efficiency of 13.0%, a luminance efficiency of 34.7 cd A(-1), and a power efficiency of 24.3 Lm W(-1). In addition, a good color rendering index (CRI) of about 74, a stable white color with a Commission Internationale de L'Eclairage (CIE(x,y)) variation of Δ(x, y) < ±(0.02, 0.02), and a correlated color temperature higher than 5130 K were obtained. These encouraging results indicate the potential of these WOLEDs as good candidates for warm indoor lighting sources, as well as the critical contribution of such key EI/ET properties to triplet emitters to advance new OLED research. 相似文献
955.
Electroluminescent (EL) spectra was employed to probe the triplet exciton diffusion length (LT) of a commonly used host material of N,N′-dicarbazolyl-3,5-benzene (mCP) in phosphorescent organic light-emitting devices (OLEDs). By varying the film thickness of bis [2-(4-tertbutylphenyl) benzothiazolato-N,C2], iridium (acetylacetonate) [(t-bt)2Ir(acac)] phosphor doped layer within 30 nm thick mCP layer, a series of devices were fabricated to investigate the EL characteristics. The results showed that with the increasing doped layer thickness (d), both (t-bt)2Ir(acac) emission peaks at 562 nm and mCP emission centered at 403 nm were observed. Moreover, the relationship between mCP EL intensity and d was detected. The LT was induced by an abrupt decrease in variation of mCP EL intensity when d is increased from 10 to 15 nm, and the reason to cause this phenomenon was investigated. The LT of mCP approximately to 15 nm was perfectly consistent to the result of 16±1 nm, which was calculated by the traditional steady-state diffusion model. 相似文献
956.
957.
本文报道了一种用于堆叠结构有机电致发光器件的新的电荷生成层: LiF/Al/V2O5,采用这种电荷生成层的堆叠器件的两个发光单元互相独立,不受影响.说明在外加电场下,这种电荷生成层具有向邻近的发光单元注入电子空穴的能力.而堆叠了两个相同发光单元的器件的电流效率在相同的电流密度下约为普通单层结构的1.7倍.同时这种电荷生成层避免了溅射indium tin oxide(ITO)和金属、有机物共掺,只需要热蒸发,生长工艺简单.
关键词:
堆叠结构
有机电致发光器件
电荷生成层 相似文献
958.
研究了掺杂离子型铱配合物的单发光层聚合物白光器件.根据二元互补色获得白光的原理,所采用离子型橙光材料为六氟磷酸合[二(2-(萘基-1-基)吡啶)(1-乙基-2-(9-(2-乙基己基)-9H-咔唑-3-基)-1H-咪唑并[4,5-f][1,10]菲啰啉)铱(Ⅲ)]([(npy)2Ir(c-phen)]PF6),天蓝光材料为二(2-(4,6-二氟苯基)吡啶-N,C(2))吡啶甲酰合铱(Firpic).器件结构为氧化铟锡/苯磺酸掺杂聚乙烯基二氧噻吩(40 nm)/发光
关键词:
聚合物发光二极管
白光
二元互补色
离子型铱配合物 相似文献
959.
采用N, N'-diphenyl-N, N'-bis(1-naphthyl-pheny1)-1, 1'-biphenyl-4, 4'-diamine (NPB):4, 4'-N, N'-dicarbazole-biphenyl (CBP) 掺杂体系为复合空穴传输层,制备了结构为indium-tin oxide (ITO)/NPB:CBP/CBP:bis iridium (acetylacetonate) /2, 9-dimethyl-4, 7-diphenyl-p
关键词:
有机电致发光器件(OLEDs)
复合空穴传输层
NPB:CBP
器件性能 相似文献
960.