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DOE OSTI · 1848479

Efficient excimer-based white OLEDs with reduced efficiency roll-off

Wu, Jiang·Ameri, Lydia·Cao, Linyu·Li, Jian
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Abstract

A tetradentate Pt(II) complex, Pt2O2-p2m, which exhibits both efficient monomer and excimer emission, was synthesized. Through rational device design to broaden the recombination zone, an OLED device employing Pt2O2-p2m demonstrated an impressively high peak external quantum efficiency (EQE) of 21.5% and a warm white emission with a color rendering index of 71 and Commission Internationale de L'Eclairage coordinates of (0.409, 0.458). Moreover, a reduced efficiency roll-off was also observed to retain high EQE values of 20% EQE at 1000 cd/m 2 and 17% EQE at 5000 cd/m 2 , and an LT70 (time to 70% initial luminance) was estimated to be over 150 h at 1000 cd/m2 under constant operation at accelerated driving conditions.

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36 MATERIALS SCIENCEColorimetryDopingElectrochemistryElectroluminescent spectraNuclear magnetic resonance spectroscopyOptical metrologyOrganic materialsPhotochemistryPhysicsPotential energy surfacesQuantum efficiency

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Wu, Jiang, Ameri, Lydia, Cao, Linyu, Li, Jian. 2021-02-19. Efficient excimer-based white OLEDs with reduced efficiency roll-off. https://doi.org/10.1063/5.0043955

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DOE OSTI2026

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