Creating Efficient Red Thermally Activated Delayed Fluorescence Materials with Cyano-Substituted 11,12-Diphenyldipyrido[3,2-a:2',3'-c]phenazine Acceptors

© 2023 Wiley-VCH GmbH..

Red luminescent materials are essential components for full color display and white lightening based on organic light-emitting diode (OLED) technology, but the extension of emission color towards red or deep red region generally leads to decreased photoluminescence and electroluminescence efficiencies. Herein, we wish to report two new luminescent molecules (2CNDPBPPr-TPA and 4CNDPBPPr-TPA) consisting of cyano-substituted 11,12-diphenyldipyrido[3,2-a:2',3'-c]phenazine acceptors and triphenylamine donors. As the increase of cyano substituents, the emission wavelength is greatly red-shifted and the reverse intersystem crossing process is promoted, resulting in strong red delayed fluorescence. Meanwhile, due to the formation of intramolecular hydrogen bonds, the molecular structures become rigidified and planarized, which brings about large horizontal dipole ratios. As a result, 2CNDPBPPr-TPA and 4CNDPBPPr-TPA can perform as emitters efficiently in OLEDs, furnishing excellent external quantum efficiencies of 28.8 % at 616 nm and 20.2 % at 648 nm, which are significantly improved in comparison with that of the control molecule without cyano substituents. The findings in this work demonstrate that the introduction of cyano substituents to the acceptors of delayed fluorescence molecules could be a facile and effective approach to explore high-efficiency red or deep red delayed fluorescence materials.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:30

Enthalten in:

Chemistry (Weinheim an der Bergstrasse, Germany) - 30(2024), 14 vom: 07. März, Seite e202303990

Sprache:

Englisch

Beteiligte Personen:

Bai, Zhentao [VerfasserIn]
Wang, Jianghui [VerfasserIn]
Zou, Peng [VerfasserIn]
Jiang, Ruming [VerfasserIn]
Yang, Dezhi [VerfasserIn]
Ma, Dongge [VerfasserIn]
Tang, Ben Zhong [VerfasserIn]
Zhao, Zujin [VerfasserIn]

Links:

Volltext

Themen:

Horizontal dipole orientation
Journal Article
Organic light-emitting diode
Red luminescent materials
Reverse intersystem crossing
Thermally activated delayed fluorescence

Anmerkungen:

Date Revised 09.03.2024

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1002/chem.202303990

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM365511986