Nanotech

woman watching on TV/ Photo By Andriy Popov via 123RF

 

There are several display technologies available in the market, including the light-emitting diode, organic light-emitting diode, and quantum dot light-emitting diode. While these displays can reproduce colors, only a little over 50 percent of the total colors generated are visible to the naked eye. This limits the maximum capacity of the display screens.

At the National University of Singapore, a research team found a way to maximize the achievable potential of displays. They used a semiconductor material called perovskite, a material having a similar type of crystal structure with calcium titanium oxide.

In the study, the researchers combined tiny perovskite crystals with a liquid monomer, a building block of polymer chains. They exposed the mixture to white light to trigger a polymerization reaction that enabled them to construct a strong, luminescent perovskite polymer composite film. Compared to a typical perovskite nanocrystal film, the new composite film had three times more efficiency.

To make the film produce colors, the researchers reviewed the set of colors perceived by the human eyes – red, green, and blue. The RGB colors are perfectly perceived by the humans because our eyes contain cone cells that are sensitive to them. 

Perovskite can produce a purer version of the RGB light and can significantly stimulate the cone cells, which was the reason why the team selected the material over other components. According to the researchers, displays enhanced by the film can produce up to 75 percent of colors.

“An added advantage is that perovskites are easy to synthesize, potentially facilitating their scale-up and reducing the production cost of displays. The time taken for perovskite precursor chemicals to react and form nanocrystals is typically on the order of 10 seconds,” explained Wong Ying Chieh, a researcher at NUS.

The team is now working with display companies to enable commercialization of the new film enhanced by perovskite.