Highly efficient tandem organic light-emitting devices employing an easily fabricated charge generation unit
Abstract
We have realized highly efficient tandem organic light-emitting devices (OLEDs) employing an easily fabricated charge generation unit (CGU) combining 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile with ultrathin bilayers of CsN3 and Al. The charge generation and separation processes of the CGU have been demonstrated by studying the differences in the current density-voltage characteristics of external-carrier-excluding devices. At high luminances of 1000 and 10000 cd/m2, the current efficiencies of the phosphorescent tandem device are about 2.2- and 2.3-fold those of the corresponding single-unit device, respectively. Simultaneously, an efficient tandem white OLED exhibiting high color stability and warm white emission has also been fabricated.
- Publication:
-
Applied Physics Express
- Pub Date:
- February 2018
- DOI:
- 10.7567/APEX.11.022101
- Bibcode:
- 2018APExp..11b2101Y