High-Efficiency, Saturated Red-Phosphorescent Polymer Light-Emitting Diodes Based on Conjugated and Non-Conjugated Polymers Doped with an Ir Complex

摘要

Recently, organic light-emitting diodes (OLEDs) based on phosphorescent dyes have attracted increasing attention clue to their potential application in full-color flat panel displays. Owing to the strong spin-orbital mixing of heavy-metal ions in phosphorescent complexes, both singlet and triplet excitons can be fully utilized, creating the possibility for electro-phosphorescent dye doped devices to reach an internal quantum efficiency of 100%. Baldo et al. first demonstrated extremely high-efficiency green phosphorescence OLEDs with /flc-tris(2-phenylpyridine)iridium, [Ir(ppy)_3]. Devices with Ir(ppy)_3 doped into 4,4'-N,N'-dicarbazole-biphenyl (CBP) and 3-phenyl-4-(l'-naphthyl)-5-phenyl-l,2,4-triazole (TAZ), show a high external quantum efficiency of 15 % ph/ el (photon/electron) and a power efficiency of 40 lm/W. By modifying the ligand structure of phosphorescent dyes, emission can be tuned over the entire visible region.'