Blue-emitting Ir(III) complexes using fluorinated bipyridyl as main ligand and 1,2,4-triazol as ancillary ligand: syntheses, photophysical properties and performances in devices

摘要

The blue-light-emitting Ir(III) complexes using 2-(3-(trifluoromethyl)-1H-1,2,4-triazol-5-yl)pyridine and fluorinated 2-phenylpyridine as ligands were synthesized and characterized in details. Their molecular structures were confirmed by H-1 NMR, FT-IR and elemental analyzer. The emission peaks of complex (F(2,4)ppy)(2)Ir(tfmptz) using 2-(2,4-difluorophenyl)pyridine as main ligand are located at 457 and 481 nm. Increasing the number of F atoms leads to a lower the lowest unoccupied molecular orbital energy level. Phosphorescent organic light-emitting devices doped the synthesized Ir(III) complexes into 4,4'-N,N'-dicarbazolebiphenyl as emitting layers were fabricated. The based-(F(3,4,5)ppy)(2)Ir(tfmptz) device shows the maximum current efficiency of 9.9 cd/A with the electroluminescent peaks at 471 and 502 nm. (C) 2016 Elsevier Ltd. All rights reserved.