Highly efficient and color-stable white organic light-emitting diode based on a novel blue phosphorescent host

- We demonstrate WOLEDs with a phosphorescent MEML architecture.
- The blue guest FIrpic was doped in a novel blue phosphorescent host.
- The efficiencies and spectra can be tuned by the thickness of interlayer and Y-EML.
- High efficiencies of 42.4 cd/A and 47.6 lm/W were realized in the optimized device.
- Device B1 exhibited nearly voltage-independent electroluminescent spectra.