Mao Meng-Xi, Li Fang-Ling, Shen Yan, Liu Qi-Ming, Xing Shuai, Luo Xu-Feng, Tu Zhen-Long, Wu Xue-Jun, Zheng You-Xuan
State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
Molecules. 2021 Apr 29;26(9):2599. doi: 10.3390/molecules26092599.
Phosphorescent iridium(III) complexes have been widely researched for the fabrication of efficient organic light-emitting diodes (OLEDs). In this work, three red Ir(III) complexes named Ir-1, Ir-2, and Ir-3, with Ir-S-C-S four-membered framework rings, were synthesized efficiently at room temperature within 5 min using sulfur-containing ancillary ligands with electron-donating groups of 9,10-dihydro-9,9-dimethylacridine, phenoxazine, and phenothiazine, respectively. Due to the same main ligand of 4-(4-(trifluoromethyl)phenyl)quinazoline, all Ir(III) complexes showed similar photoluminescence emissions at 622, 619, and 622 nm with phosphorescence quantum yields of 35.4%, 50.4%, and 52.8%, respectively. OLEDs employing these complexes as emitters with the structure of ITO (indium tin oxide)/HAT-CN (dipyra-zino[2,3-f,2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile, 5 nm)/TAPC (4,4'-cyclohexylidenebis[,-bis-(4-methylphenyl)aniline], 40 nm)/TCTA (4,4″,4″-tris(carbazol-9-yl)triphenylamine, 10 nm)/Ir(III) complex (10 wt%): 2,6DCzPPy (2,6-bis-(3-(carbazol-9-yl)phenyl)pyridine, 10 nm)/TmPyPB (1,3,5-tri(mpyrid-3-yl-phenyl)benzene, 50 nm)/LiF (1 nm)/Al (100 nm) achieved good performance. In particular, the device based on complex Ir-3 with the phenothiazine unit showed the best performance with a maximum brightness of 22,480 cd m, a maximum current efficiency of 23.71 cd A, and a maximum external quantum efficiency of 18.1%. The research results suggest the Ir(III) complexes with a four-membered ring Ir-S-C-S backbone provide ideas for the rapid preparation of Ir(III) complexes for OLEDs.
磷光铱（III）配合物已被广泛研究用于制造高效有机发光二极管（OLED）。在本工作中，使用分别带有给电子基团9,10-二氢-9,9-二甲基吖啶、吩恶嗪和吩噻嗪的含硫辅助配体，在室温下5分钟内高效合成了三种具有Ir-S-C-S四元骨架环的红色Ir（III）配合物，分别命名为Ir-1、Ir-2和Ir-3。由于4-(4-(三氟甲基)phenyl)喹唑啉的主要配体相同，所有Ir（III）配合物在622、619和622 nm处均表现出相似的光致发光发射，磷光量子产率分别为35.4%、50.4%和52.8%。以这些配合物作为发射体的OLED，其结构为ITO（氧化铟锡）/HAT-CN（二吡唑并[2,3-f,2',3'-h]喹喔啉-2,3,6,7,10,11-六腈，5 nm）/TAPC（4,4'-环己基亚基双[,-双-(4-甲基苯基)苯胺]，40 nm）/TCTA（4,4″,4″-三(咔唑-9-基)三苯胺，10 nm）/Ir（III）配合物（10 wt%）：2,6DCzPPy（2,6-双-(3-(咔唑-9-基)phenyl)吡啶，10 nm）/TmPyPB（1,3,5-三(mpyrid-3-基-phenyl)苯，50 nm）/LiF（1 nm）/Al（100 nm），表现出良好的性能。特别是，基于带有吩噻嗪单元的配合物Ir-3的器件表现出最佳性能，最大亮度为22,480 cd m，最大电流效率为23.71 cd A，最大外量子效率为18.1%。研究结果表明，具有四元环Ir-S-C-S主链的Ir（III）配合物为快速制备用于OLED的Ir（III）配合物提供了思路。
