Synthesis and Performance of Deep-Red Phosphorescent Iridium Complexes with Pyrone as an Auxiliary Ligand
Wen Jiang,
Wenming Hou,
Caixian Yan,
Zhifeng Nie,
Qiaowen Chang,
Xiangguang Li,
Weiping Liu
Affiliations
Wen Jiang
Kunming Institute of Precious Metals, Yunnan Precious Metals Laboratory Co., Ltd., Kunming 650106, China
Wenming Hou
Sino-Platinum Metals Chemical (Yunnan) Co., Ltd., Kunming 650503, China
Caixian Yan
Kunming Institute of Precious Metals, Yunnan Precious Metals Laboratory Co., Ltd., Kunming 650106, China
Zhifeng Nie
Yunnan Key Laboratory of Metal-Organic Molecular Materials and Device, School of Chemistry and Chemical Engineering, Kunming University, Kunming 650214, China
Qiaowen Chang
Kunming Institute of Precious Metals, Yunnan Precious Metals Laboratory Co., Ltd., Kunming 650106, China
Xiangguang Li
Yunnan Key Laboratory of Metal-Organic Molecular Materials and Device, School of Chemistry and Chemical Engineering, Kunming University, Kunming 650214, China
Weiping Liu
Kunming Institute of Precious Metals, Yunnan Precious Metals Laboratory Co., Ltd., Kunming 650106, China
Two bis-cyclometalated heteroleptic iridium complexes incorporating 1-phenylisoquinoline (piq) as the main cyclometalating ligand and 3-hydroxy-2-methyl-4-pyrone (ma) or 2-ethyl-3-hydroxy-4H-pyran-4-one (ema) as the auxiliary ligand, namely Ir(piq)2(ma) (Ir-1) and Ir(piq)2(ema) (Ir-2), were developed and applied as deep-red phosphors in organic light-emitting diodes (OLEDs). The two auxiliary ligands had similar influences on the photophysical, electrochemical, and electroluminescent properties of the iridium complexes. Ir(piq)2(ma) (Ir-1) showed better luminescence performance in a simple phosphorescent OLED compared to the traditional red iridium complex Ir(piq)2(acac) and exhibited a current efficiency of 9.39 cd A−1 (EQE of 12.09%). In contrast, Ir(piq)2(ema) exhibited an efficiency of 8.6 cd A−1 (EQE of 10.19%).
