Quantum dot light-emitting devices with electroluminescence tunable over the entire visible spectrum

Publication Type:

Journal Article

Source:

Nano Lett., ACS Publications, Volume 9, Issue 7, p.2532-2536 (2009)

ISBN:

1530-6984

Keywords:

2009, 2013 and earlier

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 lambda =
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.