Enhanced Operational Stability by Cavity Control of Single-Layer Organic Light-Emitting Diodes Based on Thermally Activated Delayed Fluorescence

Enhanced Operational Stability by Cavity Control of Single-Layer Organic Light-Emitting Diodes Based on Thermally Activated Delayed Fluorescence

© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.

Bibliographische Detailangaben
Veröffentlicht in:Advanced materials (Deerfield Beach, Fla.). - 1998. - 35(2023), 49 vom: 01. Dez., Seite e2304728
1. Verfasser: Li, Yungui (VerfasserIn)
Weitere Verfasser: Van der Zee, Bas, Tan, Xiao, Zhou, Xin, Wetzelaer, Gert-Jan A H, Blom, Paul W M
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2023
Zugriff auf das übergeordnete Werk:Advanced materials (Deerfield Beach, Fla.)
Schlagworte:Journal Article lifetimes optical cavities optical outcoupling organic light-emitting diodes thermally activated delayed fluorescence
Beschreibung
Zusammenfassung:© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.
Highly efficient organic light-emitting diodes (OLEDs) based on thermally activated delayed fluorescence (TADF) emitters are realized in recent years, but the device lifetime needs further improvement for practical display or lighting applications. In this work, a device design principle is presented by tuning the optical cavity of single-layer undoped devices, to realize efficient and long-lived TADF OLEDs. Extending the cavity length to the second-order interference maximum by increasing the emissive layer thickness broadens the recombination zone, while the optical outcoupling efficiency remains close to that of the thinner first-order devices. Such a device design leads to efficient and stable single-layer undoped OLEDs with a maximum external quantum efficiency of 16%, an LT90 of 452 h, and an LT50 of 3693 h at an initial luminance of 1000 cd m-2 , which is doubled compared to the first-order counterparts. It is further demonstrated that the widely-used empirical relation between OLED lifetime and light intensity originates from triplet-polaron annihilation, resulting in an extrapolated LT50 at 100 cd m-2 of close to 90 000 h, approaching the demands for practical backlight applications
Beschreibung:Date Revised 08.12.2023
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.202304728