Colloidal quantum dot light-emitting diodes employing phosphorescent small organic molecules as efficient exciton harvesters
Date
2014Source Title
Journal of Physical Chemistry Letters
Print ISSN
1948-7185
Electronic ISSN
1948-7185
Publisher
American Chemical Society
Volume
5
Issue
16
Pages
2802 - 2807
Language
English
Type
ArticleItem Usage Stats
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Abstract
Nonradiative energy transfer (NRET) is an alternative excitation mechanism in colloidal quantum dot (QD) based electroluminescent devices (QLEDs). Here, we develop hybrid highly spectrally pure QLEDs that facilitate energy transfer pumping via NRET from a phosphorescent small organic molecule-codoped charge transport layer to the adjacent QDs. A partially codoped exciton funnelling electron transport layer is proposed and optimized for enhanced QLED performance while exhibiting very high color purity of 99%. These energy transfer pumped hybrid QLEDs demonstrate a 6-fold enhancement factor in the external quantum efficiency over the conventional QLED structure, in which energy transfer pumping is intrinsically weak.
Keywords
ElectroluminescenceExcitons
Light emission
Light emitting diodes
Molecules
Optoelectronic devices
Phosphorescence
Semiconductor quantum dots
Colloidal quantum dots
Hybrid light-emitting diodes
Nonradiative energy transfer
Phosphorescent molecules
Triplet state
Energy transfer