A simple carbazole-N-benzimidazole bipolar host material for highly efficient blue and single layer white phosphorescent organic light-emitting diodes

Abstract

A new simple carbazole-N-benzimidazole bipolar luminogen mNBICz was constructed and utilized as a host for an FIrpic-doped blue device, and exhibited high efficiencies with a η_EQE,max of 26.2%, a η_C,max of 54.5 cd A⁻¹ and a η_P,max of 52.2 lm W⁻¹. Furthermore, a two-color, all-phosphor single layer white device displayed a η_EQE,max of 22.9%, a η_C,max of 62.5 cd A⁻¹ and a η_P,max of 60.4 lm W⁻¹.