Scientists have discovered that a new material originally investigated for use in solar cells is also capable of emitting light, raising the possibility for its use in display screens.

At a time where we are needing to decrease our dependency on fossil fuels, solar cells at first glance look like a great alternative. But a major hurdle exists in ensuring that the cost of the cell is balanced against its efficiency. Traditional solar cells use silicon, but alternatives are desirable since the cost of both sourcing this material and manufacturing it into solar cells can be high. This is where Perovskite comes in. Perovskite is composed of calcium titanate, and it's around five times cheaper to use than silicon in solar cell manufacture. It's also versatile and seems to be highly efficient. They used this as the base for the solar cell material. 

This material has a lot more to offer than just efficiency at capturing light energy - a group of researchers from Nanyang Technological University (NTU), Singapore, have found it has some other surprising properties. One of the scientists working on the project shone a laser beam on the solar cell, and to their surprise found that it started glowing. Solar cells are good at capturing light energy, but they usually can't generate light. Professor Sum from NTU said in a press release "By tuning the composition of the material, we can make it emit a wide range of colors, which also makes it suitable as a light emitting device, such as flat screen displays." The group published their results in Nature. 

The dream is to be able to generate a low-emission solar cell that stores energy collected during the day, which could then be used to power a colorful display at night time, for example for advertisements. The team are currently working on scaling-up the materials in order to generate large solar cells which could be used on buildings, for example by replacing tinted windows, in an attempt to make them more environmentally friendly. Perhaps one day this material could be used in technology such as smart phones or tablet computers, so that you don't have to worry about running out of battery!