Quantum Dot Light-Emitting Devices with Electroluminescence Tunable over the Entire Visible Spectrum

TitleQuantum Dot Light-Emitting Devices with Electroluminescence Tunable over the Entire Visible Spectrum
Publication TypeJournal Article
Year of Publication2009
AuthorsAnikeeva, PO, Halpert, JE, Bawendi, MG, Bulovic, V
JournalNano Letters
Volume9
Issue7
Pagination2532 - 2536
Date Published2009/07//
Abstract

Improvements in quantum dot light-emitting device (QD-LED) performance are achieved by the choice of organic charge transporting layers, by use of different colloidal QDs for the different parts of the visible spectrum, and by utilizing a recently demonstrated robust QD deposition method. Spectrally narrow electroluminescence of our QD-LEDs is tuned over the entire visible wavelength range from lambda = 460 nm (blue) to 650 nm (deep red). By printing close-packed monolayers of different OD types inside an identical OD-LED structure, we demonstrate that different color QD-LEDs with QDs of different chemistry can be fabricated on the same substrate. We discuss mechanisms responsible for efficiency increase for green (4-fold) and orange (30%) QD-LEDs as compared to previous reports and outline challenges associated with achieving high-efficiency blue QD-LEDs.