Carbon–Nitrogen Axial Chirality as a Novel Chiral Framework Design Strategy for Circularly Polarized Luminescence Materials

Abstract

Circularly polarized luminescence (CPL) materials are essential for advanced optoelectronic applications, yet efficient chiral design strategies remain challenging. Axial chirality has been widely employed in the construction of CPL materials due to its unique rigid structure. However, the focus has been primarily on the derivatives of carbon–carbon axial chirality. We herein propose a strategy for constructing carbon–nitrogen (C─N) axially chiral molecular frameworks to fully exploit the excellent chromophoric properties of nitrogen-containing heterocycles (such as carbazole). A pair of chiral emitters, (S/R)-AI-2TCFC, was designed and synthesized, exhibiting an emission peak at 578 nm both in the toluene solution and in the neat film state. It possessed typical aggregation-induced emission (AIE), thermally activated delayed fluorescence (TADF), and a luminescence dissymmetry factor (g_lum) of 10⁻³, demonstrating its potential for high-performance device applications. These materials were successfully applied in circularly polarized organic light-emitting diodes (CP-OLEDs), demonstrating promising electroluminescence performance. This innovative strategy not only expands the design toolbox for CPL materials but also paves the way for next-generation high-performance optoelectronic devices.