Carbazole-based coplanar molecule (CmInF) as a universal host for multi-color electrophosphorescent devices
作者:Cheuk-Lam Ho、Liang-Chen Chi、Wen-Yi Hung、Wei-Jiun Chen、Yu-Cheng Lin、Hao Wu、Ejabul Mondal、Gui-Jiang Zhou、Ken-Tsung Wong、Wai-Yeung Wong
DOI:10.1039/c1jm13794h
日期:——
The synthesis, isomerism, photophysics and electrophosphorescent characterization of some functional cyclometallated iridium(III) complexes containing 2-[2-(N-phenylcarbazolyl)]pyridine and 2-[3-(N-phenylcarbazolyl)]pyridine molecular frameworks are described. A carbazole-based coplanar molecule (CmInF) obtained through the intramolecular ring closure of aryl substitutions at the C3 and C6 positions exhibits a high triplet energy (ET = 2.77 eV), morphological stability (Tg = 195 °C) and hole mobility in the range of up to 5 × 10−3 cm2 V−1 s−1. Highly efficient multi-color electrophosphorescent devices have been successfully achieved employing CmInF as the universal host material doped with phosphorescent dopants of various colors under the same device configuration of ITO/PEDOT:PSS (300 Å)/TCTA (250 Å)/CmInF: dopant (250 Å)/TAZ (500 Å)/LiF/Al (PEDOT:PSS = poly(ethylene dioxythiophene):polystyrene sulfonate; TCTA = 4,4′,4′′-tri(N-carbazolyl)triphenylamine; TAZ = 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole). Through the mixing of two phosphorescent dopants of complementary colors, we also fabricated a two-color white organic light-emitting device (WOLED) with the same device structure consisting of 12 wt% FIrpic and 0.3 wt% (Mpg)22Ir(acac) co-doped into CmInF as a single-emitting-layer, which exhibits peak WOLED efficiency of 13.4% (23.4 cd A−1) and 11.2 lm W−1 with the Commission Internationale de L'Eclairage (CIE) coordinates of (0.33, 0.37). In addition, the use of such device structure in full-color OLEDs has the advantages of simplifying manufacturing process and reducing production cost that are the critical issues of commercialization.
本文描述了一些含有 2-[2-(N-苯基咔唑基)]吡啶和 2-[3-(N-苯基咔唑基)]吡啶分子框架的功能性环金属化铱(III)配合物的合成、异构、光物理和电磷光特性。通过在 C3 和 C6 位置进行芳基取代的分子内环闭合获得的咔唑基共面分子(CmInF)具有很高的三重能(ET = 2.77 eV)、形态稳定性(Tg = 195 °C)以及高达 5 × 10-3 cm2 V-1 s-1 的空穴迁移率。在相同的 ITO/PEDOT 器件配置下,采用掺杂了各种颜色磷光掺杂剂的 CmInF 作为通用宿主材料,成功实现了高效的多色电磷光器件:PSS(300 Å)/TCTA(250 Å)/CmInF:掺杂剂(250 Å)/TAZ(500 Å)/LiF/Al(PEDOT:PSS = 聚(乙烯二氧噻吩):聚苯乙烯磺酸盐;TCTA = 4,4′,4′′-三(N-咔唑基)三苯胺;TAZ = 3-(4-联苯基)-4-苯基-5-(4-叔丁基苯基)-1,2,4-三唑)。通过混合两种互补色的磷光掺杂剂,我们还制造出了一种双色白色有机发光器件(WOLED),器件结构相同,由 12 wt% FIrpic 和 0.该器件的 WOLED 峰值效率为 13.4% (23.4 cd A-1) 和 11.2 lm W-1,国际照明委员会(CIE)坐标为 (0.33, 0.37)。此外,在全彩有机发光二极管中使用这种器件结构还具有简化制造工艺和降低生产成本的优势,而这正是商业化的关键问题。