Abstract
By wisely utilizing combinations of exciton-managed orange-phosphorescence/sky blue-fluorescence, we report on high-efficiency white organic light-emitting diodes (WOLEDs) with high color-stability together with reduced efficiency roll-off. Two WOLEDs with the peak current efficiencies of 34.5 and 42.5 cd A-1which slightly shift to 34.2 and 40.0 cd A-1at 1000 cd m-2are demonstrated. Systematic investigations focused on the effects of hole-injection buffer layer, thickness of emitting-layer (EML) and the stepwise-doping profile of orange phosphorescent EML on the device performance have been performed. It is evidently shown that careful management of the triplet/singlet excitons and charge-carriers is key to realizing such high performance of the devices. The results will beyond doubt be helpful to the design of both material and device structure for high-performance WOLEDs and next-generation solid-state lighting sources.
| Original language | English |
|---|---|
| Pages (from-to) | 238-246 |
| Number of pages | 9 |
| Journal | Organic Electronics: physics, materials, applications |
| Volume | 11 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 1 Feb 2010 |
| Externally published | Yes |
Keywords
- Carbazole
- Iridium complexes
- Organic light-emitting diodes
- Triplet emission
- White light
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Biomaterials
- General Chemistry
- Condensed Matter Physics
- Materials Chemistry
- Electrical and Electronic Engineering