20 February 2018
Polishing nanocrystals to create better light-emitting devices
Published online 15 January 2018
Scientists exploit molecule-like zero-dimensional nanocrystals.
Reducing the dimensions of nanocrystals of perovskites — a specific class of inorganic materials — to zero makes them optimal candidates for use in light-emitting diodes and light-sensitive devices, according to a new study.1
The study, led by Omar Mohammed and his teammates from the King Abdullah University of Science and Technology, Thuwal, Saudi Arabia, has found that the low-dimension form of the crystals displays modifiable physical and optical properties such as enhanced light emissions.
The scientists have previously detected green emissions in zero-dimensional perovskites crystals, which prompted them to probe their properties further.
They discovered that such crystals behave exactly like organic molecules. They also noticed that they behave differently from nanoparticles and quantum dots made from three-dimensional crystals.
Made of cesium, lead and bromine atoms, the nanocrystals contain structural defects that absorb energy and emit it as green light.
“These findings provide a better understanding of the fundamental optical and physical properties of zero-dimensional materials, opening new avenues for designing low-dimensional crystals for optical and electronic devices,” says Mohammed.
Understanding these crystals can also throw light on the behaviour of light-induced charge carriers in zero-dimensional material systems, he adds.
- Yin, J. et al. Molecular behavior of zero-dimensional perovskites. Sci. Adv. http://dx.doi.org/10.1126/sciadv.1701793 (2017)