文摘
Two heteroleptic iridium(III) complexes using carbene as cyclometalated ligands and pyridine-triazole as ancillary ligand, namely (fpmi)2Ir(mtzpy) (1) and (fpmi)2Ir(phtzpy) (2) [fpmi聽=聽1-(4-fluorophenyl)-3-methylimdazolin-2-ylidene-C,C2鈥?/sup>, mtzpy聽=聽2-(5-methyl-2H-1,2,4-triazol-3-yl)pyridine, phtzpy聽=聽2-(5-phenyl-2H-1,2,4-triazol-3-yl)pyridine], were synthesized and their structural, photophysical and electrochemical properties investigated systematically. Both complexes exhibit bright greenish-blue phosphorescence (位max 鈭?90聽nm) with quantum yields of about 0.50. Comprehensive density functional theory (DFT) approach was then performed to gain insights into their photophysical and electrochemical characters. The fabrication of organic light-emitting diodes (OLEDs), employing complexes 1 and 2 as phosphorescent dopants, was successfully achieved. Among them, the device based on 1 exhibited considerable power efficiency (畏p) of 11.43聽lm聽W鈭? and current efficiency (畏c) of 11.78聽cd聽A鈭?. With the merit of intrinsic characteristic of complex 1, a white OLED comprised of 1 and one orange phosphor (pbi)2Ir(biq) achieved a peak 畏p of 9.95聽lm聽W鈭? and 畏c of 10.81聽cd聽A鈭?, together with Commission Internationale de l'Eclairage (CIE) coordinates of (0.34, 0.40). The results indicate that two iridium(III) complexes reported here are promising phosphorescent dyes for OLEDs.
