Researchers create brighter green quantum dots for higher color space

A team of scientists from Queen’s University in Belfast, among others, has developed a method that allows quantum dots to emit the color green much brighter than with regular methods. This could significantly increase the color space of TVs.

The researchers have made quantum dots consisting of methylammonium-lead bromide. When they applied layered structures with different materials, the human eye appeared to react very strongly to the visible light. According to the researchers, this means that the material emitted a lot of light and that very bright colors were created. This process is called aggregation-induced emission.

With the new method, the brightest green color to date can be created with nanomaterials. If this bright green is integrated with the other basic colors blue and red, the researchers say it will be possible to generate new color combinations that go beyond what is currently possible with quantum dots. In addition, the nanocrystals are able to emit light ‘extremely quickly’ and are very energy efficient.

The team leader of the research team at Queen’s University, Elton Santos, says that this can increase the number of colors that a monitor can display by more than fifty percent. He says that based on this method, a new type of “high-definition” screens could be introduced within three or four years.

Santos believes this method could revolutionize the color reproduction of TVs, although he did not specify what the reproduction of more colors means specifically for increasing the color space. For example, it is not stated whether it can display a high percentage of the rec2020 color space, for example.

Chih-Jen Shih, the leader of a participating Swiss research institute, explains that the quantum yield, which indicates the brightness, normally decreases considerably once the quantum dots are grouped together. According to him, higher brightness values ​​are possible with the new method.

At the moment, the researchers are copying the process for the red and blue color. According to Shih, the research is almost ready to be used commercially. All that remains to be done is to further stabilize the chemical compounds and ensure that they can withstand high temperatures, humidity and electricity.

Quantum dots are small nanocrystals from two to ten nanometers that can display colors based on their size. For example, TV manufacturers can apply them by placing a thin film with the crystals in front of the backlight, which gives the screens a higher color saturation. Several manufacturers, such as Samsung and LG, make LCD TVs with quantum dots.

The study, conducted by scientists from Queen’s University, Florida State University and Taiwan University of Science and Technology, among others, was published in the scientific journal Science Advances, under the title ‘Aggregation-induced emission in lamellar solids of colloidal perovskite quantum wells’.