Highly efficient polymer phosphorescent light-emitting devices based on a new polyfluorene derivative as host

• Published in: Chinese physics B Vol. 20; no. 8; pp. 491 - 494
• Main Authors: Wang, Bao-Zheng, Liu, Jie, Wu, Hong-Bin, Zhang, Bin, Wen, Shang-Sheng, Yang, Wei
• Format: Journal Article
• Language: English
• Published: 01.08.2011
• Subjects: Bulbs; Derivatives; Devices; Doping; Dyes; Electroluminescence; Iridium; Optimization; 主机; 共轭聚合物; 掺杂浓度; 电致发光光谱; 磷光; 聚合物发光器件; 芴衍生物; 设备
• ISSN: 1674-1056; 2058-3834
• DOI: 10.1088/1674-1056/20/8/088502

Several highly efficient iridium-complex polymer light-emitting devices （PLEDs） are fabricated, with a newly synthesized blue conjugated polymer, poly[（9,9-bis（4-（2-ethylhexyloxy）phenyl）-fluorene）-co-（3,7-dibenziothiene-S,S- dioxide15）] （PPF-3,TSO15）, chosen as host. High luminous efficiencies of 7.4 cd.A-1 and 27.4 cd.A-1 are achieved in red and green PLEDs, respectively, by optimizing the doping concentrations of red phosphorescent dye iridium bis（1- phenylisoquinoline） （acetylacetonate） （Ir（piq）） and green phosphorescent dye iridium tris（2-（4-tolyl）pyridinato-N, C2＇） （Ir（mppy）3）.Furthermore, highly efficient white PLEDs （WPLEDs） with the Commission Internationale de l＇Eclairage （CIE） coordinates of （0.35, 0.38） are successfully produced by carefully controlling the doping concentration of the irid- ium complex. The obtained WPLEDs show maximal efficiencies of 14.4 cd.A-1 and 10.1 lm.W-1, which are comparable to those of incandescent bulbs. Moreover, the electroluminescent spectrum of the white device with an initial luminance of about 1000 cd.m-2 is stable, subject to constant applied current stress, indicating that good device stability can be obtained in this system.