Introduction of extra carbazole donor to form the D′–A–D type TADF emitters did not disturb the emitting color, but reduced intermolecular interactions and exciton quenching, thus improved the EQE in OLEDs and eliminated efficiency decay.
Colour tunable TADF emitters with strong AIE characteristics exhibited EQEs above 20%.
Linear acenes, such as naphthalene, can act as acceptors in donor–acceptor type TADF emitters. We demonstrate this strategy through a computational screen and by synthesizing a novel diphenoxazine-substituted naphthalene TADF emitter.
Y- (67dPXZ-FQ) and T-shaped (58dPXZ-FQ) compounds were developed using 2-phenylfuro[2,3-b]quinoxaline and 10-phenyl-10H-phenoxazine as acceptor and donor, respectively. The effect of molecular configuration on their photophysical property was investigated.
Two orange-red emission circularly polarized thermally activated delayed fluorescence emitters (R)-ad-PXZ/(S)-ad-PXZ were synthesized. The solution processable device exhibits the maximum external quantum efficiency of 9.0% and gEL value of 10−3.