Synthesis and photoelectric performances of blue-green emitting iridium phenylpyridine complexes using N,N′-heteroaromatic ancillary ligands

Abstract

Four iridium complexes containing different ancillary ligands Htfmpptz = 2-(5-(4-(trifluoromethyl)phenyl)-2H-1,2,4-triazol-3-yl)pyridine, Hfpptz = 2-(5-(4-fluorophenyl)-2H-1,2,4-triazol-3-yl)pyridine and Htfmptz = 2-(5-(trifluoromethyl)-2H-1,2,4-triazol-3-yl)pyridine and ppy (2-phenylpyridine) as main ligands were synthesized and characterized. Their molecular structures were identified by X-ray single crystal diffraction. The effects of ancillary ligands on the photophysical and luminescence behaviors were investigated. The emission maximum peaks of (ppy)₂Ir(tfmpptz), (ppy)₂Ir(fpptz) and (ppy)₂Ir(tfmptz) in CH₂Cl₂ solution appear at 485, 487 and 483 nm, respectively. Phosphorescent organic light-emitting devices (PhOLEDs) were fabricated using these complexes doped in CBP as an emitting layer.