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DOE OSTI · 2418045

Efficient, Color-Stable, and Long-Lived White Organic Light-Emitting Diodes Utilizing Phosphorescent Molecular Aggregates

Ameri, Lydia·Cao, Linyu·Tan, Xinqiang·Li, Jian
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Abstract

Highly efficient and stable single-stack hybrid white organic light-emitting diode (WOLED) devices are developed using two emissive layers: one with amber-colored phosphorescent molecular-aggregate emission from the Pd(II) complex, Pd(II) 7-(3-(pyridine-2-yl-κN)phenoxy-κC)(benzo-κC)([c]benzo[4,5]imidazo-κN)[1,2-a][1,5]naphthyridine, Pd3O8-Py5, and the other with blue fluorescence emission. Here, an optimized device structure achieves high color stability under various current densities, an external quantum efficiency (EQE) of 45.5%, a power efficiency of 97.4 Lm W -1 , and an estimated LT 95 (operational time to 95% of the initial luminance) of 50 744 h at an initial luminance of 1000 cd m -2 .

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36 MATERIALS SCIENCEChemistryMaterials SciencePhysicsScience & Technology - Other TopicsWhite OLEDcolor stabilityfluorescencemolecular-aggregatesoperational stabilityphosphorescence

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Ameri, Lydia, Cao, Linyu, Tan, Xinqiang, Li, Jian. 2023-01-04. Efficient, Color-Stable, and Long-Lived White Organic Light-Emitting Diodes Utilizing Phosphorescent Molecular Aggregates. https://doi.org/10.1002/adma.202208361

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