Leuven, Belgium--Two researchers at Imec have developed a way to use metal nanoclusters as light emitters, making the clusters possible candidates for use in LEDs.1 The clusters of metal nanocrystals, which serve as quantum-confinement-based emitters, are synthesized into thin films; gold (au) nanoclusters produce light with a peak wavelength of 750 nm, while silver (Ag) nanoclusters produce light at 695 nm. The films are fabricated easily using solution-based processing.
Bjoern Niesen, who also works at École Polytechnique Fédérale de Lausanne (EPFL; Neuchatel, Switzerland), and Barry Rand, who is now an assistant professor at Princeton University, created LED films in which the electroluminescence peak of the LED matched with the earlier-measured photoluminescence of the MNCs in a solution state. The thin-film LED emits spectrally pure light with no parasitic emissions arising elsewhere in the LED. The threshold emission voltages for the Ag and Au based devices were 1.74 and 2.21 V, respectively.
The two researchers presented their results in December, 2013 at the Materials Research Society (MRS) Fall Meeting in Boston, MA (see https://mrsfall13.zerista.com/event/member/94683).
REFERENCE:
1. Bjoern Niesen and Barry P. Rand, Advanced Materials (2013); doi: 10.1002/adma.201304725