Typically, the material used to absorb sunlight and turn it into energy is not good at emitting light. But scientists have discovered a substance that does just that. It could mean that future smartphones or tablets have displays that both harvest sunlight and play video or display images.
Developed by scientists at Nanyang Technological University (NTU) in Singapore, the solar cell is made from Perovskite, a material that not only glows when electricity is passed through it, but can also be modified to produce various colors.
Researchers say the discovery is vital to creating inexpensive, high-efficiency solar cells of the future. Potential applications include solar-powered billboards that harness sunlight during the day and transfer to glowing advertisements at night.
“What we have discovered is that because it is a high-quality material, and very durable under light exposure, it can capture light particles and convert them to electricity, or vice versa,” NTU physicist Sum Tze Chien told Phys.org. “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 chance discovery was made when Sum asked one of his postdoctoral researchers to shine a laser on the Perovskite material. Since most solar cell material is good at absorbing, not producing light, the research team was surprised when the Perovskite glowed brightly.
Sum’s researcher partner, Nripan Mathews from the School of Materials Science and Engineering and the Energy Research Institute, believes the discovery will motivate the energy industry to adapt the material into existing technologies.
“The fact that it can also emit light makes it useful as light decorations or displays for the facades of shopping malls and offices,” Mathews said. ”Such a versatile yet low-cost material would be a boon for green buildings. Since we are already working on the scaling up of these materials for large-scale solar cells, it is pretty straightforward to modify the procedures to fabricate light-emitting devices as well.”