Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7906908 | Optical Materials | 2018 | 4 Pages |
Abstract
Dry process-able host materials are well suited to realize high performance phosphorescent organic light-emitting diodes (OLED) with precise deposition of organic layers. We demonstrate in this study high efficiency green and blue phosphorescent OLED devices by employing 3-[bis(9-ethylcarbazol-3-yl)methyl]-9-hexylcarbazole based host material. By doping a typical green emitter of fac tris(2-phenylpyridine)iridium (Ir (ppy)3) in the compound the resultant dry-processed green device exhibited superior performance with low turn on voltage of 3.0â¯V and with peak efficiencies of 11.4%, 39.9â¯cd/A and 41.8 lm/W. When blue emitter of bis [2-(4,6-difluorophenyl)pyridinato-C2,N](picolinato)iridium (III) was used, the resultant blue device showed turn on voltage of 2.9â¯V and peak efficiencies of 9.4%, 21.4â¯cd/A and 21.7 lm/W. The high efficiencies may be attributed to the host possessing high triplet energy level, effective host-to-guest energy transfer and effective carrier injection balance.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Saulius Grigalevicius, Daiva Tavgeniene, Gintare Krucaite, Dovydas Blazevicius, Raimonda Griniene, Yi-Ning Lai, Hao-Hsuan Chiu, Chih-Hao Chang,