Asymmetric anthracene host decorated with benzothienocarbazole for high efficiency blue organic light-emitting diodes

Abstract

In this work, we describe an asymmetric anthracene-based 5-(4-(10-phenylanthracen-9-yl)phenyl)-5H-benzo [4,5]thieno[3,2-c]carbazole (ATDBT) for high efficiency doped and non-doped organic light-emitting diodes (OLEDs). Anthracene triggered triplet-triplet annihilation and structurally induced bipolar characteristics of the ATDBT significantly accelerated the triplet to singlet up-conversion process. The fabricated devices eventually achieved high efficiency with a small efficiency roll-off at high luminance. The doped device with ATDBT as the host has a maximum external quantum efficiency (EQE) of more than 8%, pure-blue emission, and maximum luminance of more than 40,000 cd/m2. The non-doped ATDBT device also showed a high EQE of 4.9%. As a result, ATDBT-type asymmetric molecular structures are vital for the development of high-efficiency doped and non-doped blue OLEDs.