Bright green electroluminescence with an EQE of 4.6% from a host–guest OLED fabricated from an unsymmetric liquid crystalline N-annulated perylene ester imide as a dopant

Abstract

This study reports an unsymmetrical liquid crystalline, N-annulated perylene diester imide (PEI-N^ST), featuring a swallow tail substituent through imide linkage and straight chain substituents through ester linkages. It showed an impressive photoluminescence quantum yield (PLQY) of 91% and demonstrated outstanding performance in a CBP-doped OLED device at its 0.5 wt% concentration, yielding an EQE max of 4.6% accompanied by a bright luminescence of 5 269 cd m⁻².