Title |
Highly efficient blue electroluminescence based on thermally activated delayed fluorescence
|
---|---|
Published in |
Nature Materials, December 2014
|
DOI | 10.1038/nmat4154 |
Pubmed ID | |
Authors |
Shuzo Hirata, Yumi Sakai, Kensuke Masui, Hiroyuki Tanaka, Sae Youn Lee, Hiroko Nomura, Nozomi Nakamura, Mao Yasumatsu, Hajime Nakanotani, Qisheng Zhang, Katsuyuki Shizu, Hiroshi Miyazaki, Chihaya Adachi |
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%. |
X Demographics
Geographical breakdown
Country | Count | As % |
---|---|---|
United Kingdom | 1 | 20% |
Australia | 1 | 20% |
Japan | 1 | 20% |
Unknown | 2 | 40% |
Demographic breakdown
Type | Count | As % |
---|---|---|
Members of the public | 4 | 80% |
Scientists | 1 | 20% |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
Germany | 3 | <1% |
United States | 3 | <1% |
Japan | 2 | <1% |
Belgium | 2 | <1% |
United Kingdom | 1 | <1% |
Singapore | 1 | <1% |
China | 1 | <1% |
Unknown | 423 | 97% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Student > Ph. D. Student | 124 | 28% |
Researcher | 74 | 17% |
Student > Master | 50 | 11% |
Student > Bachelor | 33 | 8% |
Student > Doctoral Student | 23 | 5% |
Other | 48 | 11% |
Unknown | 84 | 19% |
Readers by discipline | Count | As % |
---|---|---|
Chemistry | 189 | 43% |
Materials Science | 56 | 13% |
Physics and Astronomy | 48 | 11% |
Engineering | 32 | 7% |
Biochemistry, Genetics and Molecular Biology | 3 | <1% |
Other | 10 | 2% |
Unknown | 98 | 22% |