Title

Highly efficient quantum-dot light emitting diodes with DNA-CTMA as combined hole transporting and electron-blocking layer

Document Type

Article

Publication Date

2-17-2009

Publication Source

ACS Nano

Abstract

Owing to their narrow bright emission band, broad size-tunable emission wavelength, superior photostability, and excellent flexible-substrate compatibility, light-emitting diodes based on quantum dots (QD-LEDs) are currently under intensive research and development for multiple consumer applications including flat-panel displays and flat lighting. However, their commercialization is still precluded by the slow development to date of efficient QD-LEDs as even the highest reported efficiency of 2.0% cannot favorably compete with their organic counterparts. Here, we report QD-LEDs with a record high efficiency (∼4%), high brightness (∼6580 cd/m2), low turn-on voltage (∼2.6 V), and significantly improved color purity by simply using deoxyribonucleic acid (DNA) complexed with cetyltrimetylammonium (CTMA) (DNA−CTMA) as a combined hole transporting and electron-blocking layer (HTL/EBL). This, together with controlled thermal decomposition of ligand molecules from the QD shell, represents a novel combined, but simple and very effective, approach toward the development of highly efficient QD-LEDs with a high color purity.

Inclusive pages

737–743

ISBN/ISSN

1936-0851

Publisher

ACS Publication

Volume

3

Issue

3

Peer Reviewed

yes

Keywords

quantum dot, light-emitting diode (LED), QD-LED, DNA, flat display