Molecular design and synthetic approach to C2,C3,C4-modified carbazoles: high triplet energy bipolar host materials for efficient blue phosphorescent organic light emitting diodes†
Abstract
Herein, we report the first examples of the design of and synthetic approach to C3/C4 and C2/C3/C4-modified carbazole based high triplet energy bipolar host materials for blue phosphorescent organic light emitting diodes and demonstrated excellent device performance with the maximum external quantum efficiency as high as 25.3% and current efficiency of 48.1 cd A−1.