Ultrastrong Red Circularly Polarized Luminescence Promoted from Chiral Transfer and Intermolecular Forster Resonance Energy Transfer in Ternary Chiral Emissive Nematic Liquid Crystals

Chiral emissive liquid crystals N*-LCs) have been proved to greatly amplify the circularly polarized luminescence (CPL) signals due to highly regular spiral arrangement of dyes in a well-organized liquid crystals system. Normally, CPL materials with a high luminescence dissymmetry factor (g(lum)) and quantum yield (QY) can meet the real application requirement. Here, four chiral aggregate-induced emission (AIE) active donors (Guests Al -A4: R-C2, R-C4, R-C6, R-C8, chiral dopant, and energy donor) and achiral ME-active acceptors (Guest B: PBCy, CPL emitter) were doped into the commercial nematic liquid crystals E7 (N-LCs, Host) to form CPL-active ternary chiral emissive N-LCs (T-N*-LCs), respectively. This kind of T-N*-LCs could emit strong red CPL with QY = 16.56% and g(lum) up to 1.51 through intermolecular energy transfer and chirality induction from the supramolecular self-assembly of T-N*-LCs. This work provides the effective strategy for the development of high g(lum) CPL materials.

Automated summary

Chiral emissive liquid crystals (N*-LCs) have been shown to significantly enhance circularly polarized luminescence (CPL) signals due to a regular spiral arrangement of dyes. By doping AIE active donors and ME active acceptors into N-LCs, CPL-active ternary chiral emissive N-LCs (T-N*-LCs) are formed, which can emit strong red CPL through intermolecular energy transfer and chirality induction. This work provides an effective strategy for developing high g(lum) CPL materials.