Programmable Circularly Polarized Electroluminescence Through Stereocontrol of Chiral Liquid‐Crystalline Co‐Assemblies
Yu Zhang, Pengxiang Wang, Zhenhao Jiang, Dong Li, Hang Li, Yixiang Cheng
Abstract
Abstract Circularly polarized organic light‐emitting diodes (CP‐OLEDs) are essential to prospective 3D displays and advanced polarized lighting systems. The rational design of programmable circularly polarized electroluminescence (CP‐EL) materials with a large electroluminescence dissymmetry factor ( g EL ) remains a great challenge and is still in its preliminary exploration phase. In this work, two aggregation induced emission active (AIE‐active) chiral inducers with different dihedral angles of binaphthalene ( S ‐/ R ‐1 and S ‐/ R ‐2) and achiral acrylate‐based liquid crystalline polymer (LCP) (PyP) were chosed to construct chiral co‐assemblies through an intermolecular chirality induction mechanism. Interestingly, as the dihedral angle of the AIE‐active binaphthyl inducer decreased from obtuse to acute angle, the resulting co‐assemblies ( S ‐/ R ‐2‐PyP) could emit inverted and amplified CP‐EL signals compared with S ‐/ R ‐1‐PyP after annealing. Significantly, the ( S ‐/ R ‐2) 0.1 ‐(PyP) 0.9 ‐based CP‐OLEDs displayed remarkable blue CP‐EL ( λ EL = 480 nm, L max = 14860 cd m −2 ) with a record | g EL | value of up to 0.18 in chiral co‐assembled CP‐OLEDs to date. This work describes the first observation of dynamic CP‐EL with tunable signal direction and intensity through stereocontrol of AIE‐active chiral inducers in LCP co‐assembled films, providing a valuable guidance for realizing programmable CP‐EL.