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

Today Krisztian is presenting the paper:

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

Polina O. Anikeeva†^‡, Jonathan E. Halpert†^§, Moungi G. Bawendi^§ and Vladimir Bulovi*

Nano Lett., 2009, 9 (7), pp 2532–2536

DOI: 10.1021/nl9002969

Publication Date (Web): June 10, 2009

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 λ = 460 nm (blue) to λ = 650 nm (deep red). By printing close-packed monolayers of different QD types inside an identical QD-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.