Efficient Orange and White Circularly Polarized Electroluminescence from Inherently Chiral Thermally Activated Delayed Fluorescence Materials

Abstract Heteroatom‐embedded cyclic compounds offer significant advantages for organic optoelectronic materials. Herein, two novel saddle‐shaped, inherently chiral eight‐membered ring thermally activated delayed fluorescence (TADF) materials (M8TPN and D8TPN), based on donor–acceptor (cyano–carbazole) structure, are presented. The involvement of chiral groups in the electronic distribution and emission process results in impressive circularly polarized luminescence (CPL) performances of the chiral materials with dissymmetry factors (g_PL) reaching up to 7 × 10⁻³. Remarkably, the corresponding circularly polarized organic light‐emitting diodes (CP‐OLEDs) with the (cR/cS)‐D8TPN material containing two eight‐membered rings enable orange–red and white light emission when doped into different host materials, achieving external quantum efficiencies of 7.91% and 12.8%, respectively, comparable to those of classical cyano– carbazole‐based TADF emitters. Furthermore, these devices exhibit efficient circularly polarized electroluminescence with |g_EL| values of 4.8 × 10⁻³ and 1.6 × 10⁻³, respectively. This work represents the first application of eight‐membered inherently chiral compounds in CP‐OLEDs, offering an avenue for future material design.