Format

Send to

Choose Destination
Nat Mater. 2015 Mar;14(3):330-6. doi: 10.1038/nmat4154. Epub 2014 Dec 8.

Highly efficient blue electroluminescence based on thermally activated delayed fluorescence.

Author information

1
Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan.
2
1] Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan [2] Research &Development Department, Dyden Corporation, 1-1 Hyakunenkouen, Kurume, Fukuoka 839-0864, Japan.
3
1] Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan [2] Advanced Core Technology Laboratories, Fujifilm Corporation, 577 Ushijima, Kaisei, Ashigarakami, Kanagawa 258-8577, Japan.
4
1] Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan [2] JST, ERATO, Adachi Molecular Exciton Engineering Project, 744 Motooka, Nishi, Fukuoka 819-0395, Japan.
5
1] Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan [2] JST, ERATO, Adachi Molecular Exciton Engineering Project, 744 Motooka, Nishi, Fukuoka 819-0395, Japan [3] Innovative Organic Device Laboratory, Institute of Systems, Information Technologies and Nanotechnologies (ISIT), 744 Motooka, Nishi Fukuoka 819-0395, Japan.
6
1] Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan [2] Nippon Steel &Sumikin Chemical Co. Ltd., 46-80, Nakabaru Sakinohama, Tobata, Kitakyushu 804-8503, Japan.
7
1] Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan [2] JST, ERATO, Adachi Molecular Exciton Engineering Project, 744 Motooka, Nishi, Fukuoka 819-0395, Japan [3] International Institute for Carbon Neutral Energy Research, Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395, Japan.

Abstract

Organic compounds that exhibit highly efficient, stable blue emission are required to realize inexpensive organic light-emitting diodes for future displays and lighting applications. Here, we define the design rules for increasing the electroluminescence efficiency of blue-emitting organic molecules that exhibit thermally activated delayed fluorescence. We show that a large delocalization of the highest occupied molecular orbital and lowest unoccupied molecular orbital in these charge-transfer compounds enhances the rate of radiative decay considerably by inducing a large oscillator strength even when there is a small overlap between the two wavefunctions. A compound based on our design principles exhibited a high rate of fluorescence decay and efficient up-conversion of triplet excitons into singlet excited states, leading to both photoluminescence and internal electroluminescence quantum yields of nearly 100%.

PMID:
25485987
DOI:
10.1038/nmat4154

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center