Flexible Ink‐Jet Printed Polymer Light‐Emitting Diodes using a Self‐Hosted Non‐Conjugated TADF Polymer

• Published in: Macromolecular rapid communications. 2023-06, Vol.44 (12), p.e2300015-n/a
• Main Authors: Cole, Cameron M., Kunz, Susanna V., Baumann, Thomas, Blinco, James P., Sonar, Prashant, Barner‐Kowollik, Christopher, Yambem, Soniya D.
• Format: Article
• Language: English
• Subjects: Emitters; Fabrication; flexible electronics; Fluorescence; ink‐jet printing; Luminance; Organic light emitting diodes; Polymers; self‐hosted polymers; solution‐processability; thermally activated delayed fluorescence polymers
• ISSN: 1022-1336; 1521-3927
• DOI: 10.1002/marc.202300015

Thermally activated delayed fluorescent (TADF) emitters have become the leading emissive materials for highly efficient organic light‐emitting diodes (OLEDs). The deposition of these materials in scalable and cost‐effective ways is paramount when looking toward the future of OLED applications. Herein, a simple OLED with fully solution‐processed organic layers is introduced, where the TADF emissive layer is ink‐jet printed. The TADF polymer has electron and hole conductive side chains, simplifying the fabrication process by removing the need for additional host materials. The OLED has a peak emission of 502 nm and a maximum luminance of close to 9600 cd m−2. The self‐hosted TADF polymer is also demonstrated in a flexible OLED, reaching a maximum luminance of over 2000 cd m−2. These results demonstrate the potential applications of this self‐hosted TADF polymer in flexible ink‐jet printed OLEDs and, therefore, for a more scalable fabrication process. A non‐conjugated polymer, carrying a thermally activated delayed fluorescent emitter pendant, a carbazole based hole‐transporting pendant, and an α‐carboline electron‐transporting pendant is ink‐jet printed as a self‐hosted emissive layer in a flexible organic light‐emitting diode.