Multi-Faceted Scientific Strategies Toward Better SSL of Phosphorescent OLEDs
Investigating Organization
University of North Texas
Principal Investigator(s)
Mohammad Omary
Subcontractor
University of Texas at Dallas
Funding Source
Building Technologies Program/NETL
Award
DOE Share: $1,569,868; Contractor Share: $699,228
Contract Period
10/01/06 - 08/31/10
The objective of this project is to advance phosphorescent OLEDs through targeted synthesis of new OLED emitters designed to exhibit phosphorescence with maximized brightness in the solid state and optimizing the performance of monochromatic and white OLEDs. Extensive screening has attained multiple complexes with metal-centered emissions exhibiting 100% phosphorescence quantum yield, 80-100 CRI from a single neat phosphor, and order-of-magnitude superior stability to elongated photo or electrical excitation compared to state-of-the-art common phosphors.
The project has achieved several record performances for OLEDs based on new phosphors including the following (all without outcoupling):
a) 70.6 lm/W turquoise-blue OLED from the Pt(II) bis(pyridyl)triazolate phosphor Pt(ptp)2 versus 42.8 lm/W for baseline devices using the Ir(III) phenylpyridiniate complex FIrpic.
b) 58.2 lm/W near-white OLED using a neat emissive layer, an unprecedented performance for such devices.
c) 47.1 lm/W warm-white OLED with remarkable color stability constructed from two neat emissive layers comprising a turquoise-blue and an orange phosphor.
d) 45.4 lm/W warm-white OLED with remarkable color stability constructed from a single phosphor by gradient doping. The project also identified several recipes to attain high performance and high color stability at lighting brightness while simplifying device architecture, reducing the manufacturing cost, and increasing the reproducibility of WOLEDs by avoiding doping, avoiding use of ultrathin emissive layers, and decreasing the number of deposited layers and interfaces.