B-N Covalent Bond Embedded Double Hetero-[n]helicenes for Pure Red Narrowband Circularly Polarized Electroluminescence with High Efficiency and Stability
© 2023 Wiley-VCH GmbH.
Veröffentlicht in: | Advanced materials (Deerfield Beach, Fla.). - 1998. - 36(2024), 5 vom: 11. Feb., Seite e2307420 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2024
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Zugriff auf das übergeordnete Werk: | Advanced materials (Deerfield Beach, Fla.) |
Schlagworte: | Journal Article circularly polarized electroluminescence multi-resonance operational stability organic light-emitting diodes pure-red emission |
Zusammenfassung: | © 2023 Wiley-VCH GmbH. Chiral B/N embedded multi-resonance (MR) emitters open a new paradigm of circularly polarized (CP) organic light-emitting diodes (OLEDs) owing to their unique narrowband spectra. However, pure-red CP-MR emitters and devices remain exclusive in literature. Herein, by introducing a B-N covalent bond to lower the electron-withdrawing ability of the para-positioned B-π-B motif, the first pair of pure-red double hetero-[n]helicenes (n = 6 and 7) CP-MR emitter peaking 617 nm with a small full-width at half-maximum of 38 nm and a high photoluminescence quantum yield of ≈100% in toluene is developed. The intense mirror-image CP light produced by the enantiomers is characterized by high photoluminescence dissymmetry factors (gPL ) of +1.40/-1.41 × 10-3 from their stable helicenes configuration. The corresponding devices using these enantiomers afford impressive CP electroluminescence dissymmetry factors (gEL ) of +1.91/-1.77 × 10-3 , maximum external quantum efficiencies of 36.6%/34.4% and Commission Internationale de I'Éclairage coordinates of (0.67, 0.33), exactly satisfying the red-color requirement specified by National Television Standards Committee (NTSC) standard. Notably a remarkable long LT95 (operational time to 95% of the initial luminance) of ≈400 h at an initial brightness of 10,000 cd m-2 is also observed for the same device, representing the most stable CP-OLED up to date |
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Beschreibung: | Date Revised 01.02.2024 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1521-4095 |
DOI: | 10.1002/adma.202307420 |