Helical Chiral MR‐TADF Emitters Enabling Blue Circularly Polarized OLEDs

ABSTRACT Circularly polarized organic light‐emitting diodes (CP‐OLEDs) are attracting increasing attention for next‐generation display and imaging applications. A key challenge lies in the development of emitters that can simultaneously deliver high efficiency, narrowband emission, and strong circular polarization. Herein, we report three pairs of helical CP‐MR‐TADF compounds, M / P ‐ PhCz‐QAO , M / P ‐ BFN‐QAO , and M / P ‐ BSF‐QAO , in which N ‐phenylcarbazole, dibenzofuran, and dibenzothiophene units induce intrinsic helical chirality within a carbonyl/nitrogen‐based MR‐TADF framework. This steric design enforces strong coupling between the chiral geometry and the frontier molecular orbitals. The resulting enantiomers exhibit narrowband sky‐blue photoluminescence (PL) with full widths at half maximum of 32–42 nm and solution‐state Commission International de l'Eclairage (CIE) _y coordinates of 0.08–0.14. When integrated into OLEDs, the devices achieve maximum external quantum efficiencies of up to 15.1% together with clear circularly polarized electroluminescence signals with g _EL values on the order of 10 ⁻³ . This work demonstrates a robust intrinsic chirality design strategy for achieving high‐performance CP‐MR‐TADF materials, paving the way toward efficient and spectrally pure CP‐OLEDs for advanced chiroptical optoelectronic applications.