Pure red electrophosphorescence from polymer light-emitting diodes doped with highly emissive bis-cyclometalated iridium(III) complexes
Pure red electrophosphorescence from polymer light-emitting diodes doped with highly emissive bis-cyclometalated iridium(III) complexes
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DOI：
10.1016/j.jorganchem.2010.05.011
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发表时间：
2010-08-01
影响因子：
2.3
通讯作者：
Sakurai, Yoshiaki
中科院分区：
文献类型：
--
作者：
Tsujimoto, Hidetaka;Yagi, Shigeyuki;Sakurai, Yoshiaki
为了开发高发光红色发光材料，以1-(二苯并[b，d]呋喃-4-基)异喹啉-N，C-3‘(DBfiq)环金属配体为原料，合成了新型双环金属Ir(III)配合物。当1，3-二(3，4-二丁氧基苯基)丙烷-1，3-二酸酯(BDBP)作为辅助配体时，Ir(DBfiq)2(BDBP)1在640 nm处表现出红色光致发光，量子产率(Phi(PL))为0.61(在甲苯中，298K)。将BDBP分别取代为二异丙戊酰甲酸酯(DPM)和乙酰丙酮(Acac)(Ir(Dbfiq)2(Dpm)2和Ir(Dbfiq)2(Acac)3)不影响荧光光谱，但使2和3的phi(PL)分别降低到0.55和0.49。在掺杂的聚甲基丙烯酸甲酯(PMMA)薄膜中也发现了类似的趋势，并且1的发射率(Phi(PL)0.17)比2和3(Phi(PL)0.08和0.06)强。以1为磷光掺杂剂，制备了结构为ITO/PEDOT：PSS(40 Nm)/PVCz：1：PBD(100 Nm)/CSF(1 Nm)/Al(250 Nm)的聚合物发光二极管。从所制备的PLED中获得了纯红色电致发光(EL)，其CIE色度坐标为(0.68，0.31)。在PVCz基发光层中掺入0.51mol%的1，在16.5V时的最大亮度为7270cdm(-2)，在7.5V时的功率效率为1.4lmW-1，在9.0V时的外量子效率为6.4%。用2和3制作了相同结构和成分的PLED，并研究了它们的器件特性。与荧光量子产率成正比的是，1比2和3具有更好的器件性能。由于在BDBP配体上引入了4个丁氧基，1在有机溶剂如氯仿和甲苯中表现出很高的溶解性，因此是一种优秀的溶液处理有机电致发光器件的红色磷光掺杂剂。(C)2010爱思唯尔B.V.保留所有权利。
In order to develop highly emissive red phosphorescent materials for OLED application, novel bis-cyclometalated iridium(III) complexes were developed using the 1-(dibenzo[b,d] furan-4-yl) isoquinolinato- N,C-3' (dbfiq) cyclometalating ligand. When 1,3-bis(3,4-dibutoxyphenyl) propane-1,3-dionate (bdbp) is employed as an ancillary ligand, Ir(dbfiq) 2(bdbp) 1 exhibits red photoluminescence (PL) at 640 nm with a quantum yield (Phi(PL)) of 0.61 (in toluene, 298 K). Replacement of bdbp to dipivaloylmethanate (dpm) and acetylacetonate (acac) (Ir(dbfiq) 2(dpm) 2 and Ir(dbfiq) 2(acac) 3, respectively) does not affect the PL spectrum, but reduces Phi(PL) to 0.55 and 0.49 for 2 and 3, respectively. Similar tendency is also found in the doped poly(methyl methacrylate) (PMMA) film, and 1 is more emissive (Phi(PL) 0.17) than 2 and 3 (Phi(PL) 0.08 and 0.06, respectively). Using 1 as a phosphorescent dopant, polymer light-emitting diodes (PLEDs) were fabricated, of which structure was ITO/PEDOT: PSS (40 nm)/PVCz: 1: PBD (100 nm)/CsF (1 nm)/Al (250 nm). Pure red electroluminescence (EL) is obtained from the fabricated PLEDs, affording a CIE chromaticity coordinate of (0.68, 0.31). When 0.51 mol% of 1 is incorporated in the PVCz-based emitting layer, the PLED shows maximum luminance of 7270 cd m(-2) at 16.5 V, power efficiency of 1.4 lm W-1 at 7.5 V, and external quantum efficiency of 6.4% at 9.0 V. PLEDs with the same structure and components were also fabricated using 2 and 3, and their device characteristics were investigated. In proportion to the PL quantum yields, 1 affords better device performance than 2 and 3. Owing to four butoxy groups introduced to the bdbp ligand, 1 exhibits high solubility in organic solvents such as chloroform and toluene, and thus, is an excellent red phosphorescent dopant for solution-processed OLEDs. (C) 2010 Elsevier B. V. All rights reserved.