Affiliation:
1. Kunming Institute of Precious Metals, Yunnan Precious Metals Laboratory Co., Ltd., Kunming 650106, China
2. Yunnan Key Laboratory of Metal-Organic Molecular Materials and Device, School of Chemistry and Chemical Engineering, Kunming University, Kunming 650214, China
3. Sino-Platinum Metals Chemical (Yunnan) Co., Ltd., Kunming 650503, China
Abstract
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%).
Funder
Science and Technology Project of Yunnan Precious Metals Laboratory
National Natural Science Foundation of China
Scientific Research Funds of Kunming University
Special Basic Cooperative Research Programs of Yunnan Provincial Undergraduate Universities’ Association
Yunnan Fundamental Research Projects
Kunming “Spring City Program” for Youth Top-Notch Talents
Program for Young and Middle-Aged Academic and Technical Leaders Reserve Talents of Yunnan Province
Frontier Research Team of Kunming University 2023, the High-Level Talent Plans for Young Top-Notch Talents of Yunnan Province
High-Level Talent Special Support Plans for Young Talents of Kunming City