Phenylcarbazole‐Based Phosphine Oxide Host Materials For High Efficiency In Deep Blue Phosphorescent Organic Light‐Emitting Diodes

Abstract Highly efficient deep blue phosphorescent organic light‐emitting diodes are developed using novel phenylcarbazole‐based phosphine oxide host materials (PPO1 and PPO2). A deep blue phosphorescent dopant, tris((3,5‐difluoro‐4‐cyanophenyl)pyridine) iridium, is doped into PPO1 and PPO2 at a doping concentration of 15% and a high quantum efficiency of 18.4% is obtained with color coordinates of (0.14, 0.15).