Date：2017-10-16 |
Views：1789 |
【Academic writing Sharing 20171011】 |
Novel furo[3,2-c]pyridine based iridium complex for highperformance
organic light-emitting diodes with over 30% external
quantum efficiency
Article excerpt is from:Zhimin Yan, Yanping Wang, Jiaxiu Wang, Yue Wang, Junqiao Ding, Lixiang Wang
J. Mater. Chem. C, 2017, in press
A novel furo[3,2-c]pyridine based Ir complex, namely (pfupy)2Ir(acac), has been developed by replacing sulfur with oxygen in the C^N ligand. Compared with the thiophenecontaining (pthpy)2Ir(acac), the LUMO level is elevated while the HOMO level keeps almost unchanged for the resultant furancontaining (pfupy)2Ir(acac). As a consequence, the emissive maximum is blue-shifted from 556 nm of (pthpy)2Ir(acac) to 538 nm of (pfupy)2Ir(acac) together with an improved photoluminescence quantum yield of 0.80. The corresponding device based on (pfupy)2Ir(acac) realizes a record-high external quantum efficiency (EQE) of 30.5% (110.5 cd/A) without any outcoupling technology. Even at a luminance of 1000 and 5000 cd/m2, the EQE still remains at 26.6% (96.4 cd/A) and 25.6% (92.7 cd/A),respectively, indicative of the gentle efficiency roll-off. The results clearly demonstrate the great potential of furan-based functional materials applied in OLEDs.
