High efficiency deep blue phosphorescent organic light emitting diodes using a phenylcarbazole type phosphine oxide as a host material

  • Jeon, Soon-Ok (Dept. of Polymer Science and Engineering, Dankook University) ;
  • Yook, Kyoung-Soo (Dept. of Polymer Science and Engineering, Dankook University) ;
  • Lee, Jun-Yeob (Dept. of Polymer Science and Engineering, Dankook University)
  • Published : 2009.10.12

Abstract

A high efficiency deep blue phosphorescent organic light-emitting diode (PHOLED) was developed using a new wide triplet bandgap host material (PPO1) with a phenylcarbazole and a phosphine oxide unit. The wide triplet bandgap host material was synthesized by a phosphornation reaction of 2-bromo-Nphenylcarbazole with chlorodiphenylphosphine. A deep blue emitting phosphorescent dopant, tris((3,5-difluoro-4-cyanophenyl)pyridine)iridium (FCNIr), was doped into the PPO1 host and a high quantum efficiency of 17.1 % and a current efficiency of 19.5 cd/A with a color coordinate of (0.14,0.15) were achieved in the blue PHOLED. The quantum efficiency of the deep blue PHOLED was better than any other quantum efficiency value reported up to now.

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