Inverted and Amplified CP-EL Behavior Promoted by AIE-Active Chiral Co-Assembled Helical Nanofibers.

It is well-known that high-performance circularly polarized organic light-emitting diodes (CP-OLEDs) remain a formidable challenge to the future application of circularly polarized luminescent (CPL)-active materials. Herein, we describe our design of a pair of AIE-active chiral enantiomers (L/D-HP) to construct chiral co-assemblies with an achiral naphthalimide dye (NTi). The resulting co-assemblies emit an inverted CPL signal compared with that from the L/D-HP enantiomers. After thermal annealing at 120°C, the inverted CPL signal of this kind of L/D-HP-NTi with a 1:1 molar ratio showed regular and ordered helical nanofibers arranged through intermolecularly ordered layered packing and was accompanied with a further amplified effect (|g em | = 0.032, λ em = 535 nm). Significantly, non-doped CP-OLEDs based on a device emitting layer (EML) of L/D-HP-NTi exhibited a low turn-on voltage (V on ) of 4.7 V, a high maximum brightness (L max ) of 2001 cd m -2 , and moderate maximum external quantum efficiency (EQE max ) of 2.3%, as well as excellent circularly polarized electroluminescence (CP-EL) (|g EL | = 0.023, λ em = 533 nm). This article is protected by copyright. All rights reserved.