Highly Soluble Green-Emitting Ir(III) Complexes with 9-(6-Phenyl-pyridin-3-ylmethyl)-9H-Carbazole Ligands and Their Application to Polymer Light-Emitting Diodes

Abstract

Highly organic soluble Ir(III) complexes with 9-(6-phenyl-pyridin-3-ylmethyl)-9H-carbazole were simply synthesized, and the solubility of the new complex was significantly improved when compared with the conventional green-emitting Ir(PPY)(3). Since a carbazole group is tethered through a nonconjugated methylene spacer, the photophysical properties of new complexes are almost identical with those of conventional Ir(ppy)(3). The pure complexes were utilized to prepare electrophosphorescent polymer light-emitting diodes (PLEDs). The device performances were observed to be relatively better or comparable with those of Ir(ppy)(3) based poly(N-vinylcarbazole) systems. The integration of rigid hole-transporting carbazole and phosphorescent complex provides a new route to design highly efficient solution-processable complex for electrophosphorescent PLED applications. (C) 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7419-7428, 2008