Efficient bipolar AIE emitters for high-performance nondoped OLEDs

Three luminogens were designed and synthesized by integratingTPEwith hole-transporting carbazole (Cz) and/or electron-transporting 1,2-diphenyl-1H-benzimidazole (PBi), and bare tetraphenylethene and another donor-acceptor (D-A) compound with aggregation-caused quenching (ACQ) were also prepared for comparison. In nondoped OLEDs, the best one with both aggregation-induced emission (AIE) properties and donor-acceptor (D-A) structures showed excellent performances withL(max), CEmax, PEmax, and EQE(max)of 24 308 cd m(-2), and 15.10 cd A(-1), 14.82 lm W-1, and 5.34%, respectively, which reached the theoretical limit of fluorescent OLEDs.