Researchers at the University of Surrey have made strides in no-emission energy technology on Monday, Feb. 29th with clear, flexible solar panels inspired by moth eyes.
Graphene, a clear, conductive material that is 100 times stronger than the strongest steel while still being as bendable as rubber. While it conducts electricity well, it could only absorb 2.3% of sunlight that hit it – until now.
By making graphene sheets that mimic the pattern of a moth’s eye, researchers have made the material able to absorb 90% of sunlight, even indoors.
“We realized that the moth’s eye works in a particular way that traps electromagnetic waves very efficiently,” said Professor Ravi Silva, head of the Advanced Technology Institute at Surrey. “As a result of our studies, we’ve been able to mimic the surface of a moth’s eye and create an amazingly thin, efficient, light-absorbent material made of graphene.”
Channels in a moth’s eye redirects small amounts of light toward the center of the eye, and in replicating the pattern of channels, Silva and his team believe they have created the most light-absorbant material ever.
The team at Surrey believes their graphene panels can be used to make flexible smartphones and artificial retinas. “Smart clothing” and “smart wallpaper” are also being considered, meaning touch-screen clothes and walls made of graphene may be in the near future.
Graphene is comprised of one-atom sheets of carbon atoms, arranged in a honeycomb pattern. It was first observed in 1962 but largely ignored, only to be re-examined in 2004 at the University of Manchester.
Since then, scientists have been searching for practical uses for the amazing material. It has generally only been used in powder form, being mixed into paint and printer inks to reduce the possibility of being ruined by the outside environment.
“For many years people have been looking for graphene applications that will make it into mainstream use,” Silva says. “We are finally now getting to the point where these applications are going to happen. We think that with this work that is coming out, we can see an application that is very close because we’ve done something that was previously thought impossible: optimizing its incredible optical properties.”
Silva explains that the graphene sheets don’t need just sunlight for energy, but can also capture ambient energy, such as energy from microwaves and radio waves, and convert it to electricity.
““Organic solar cells are based on polymers and these only really capture energy from the visible range. Now with the materials we have, it transcends all of that by being able to absorb over a much larger range,” says Silva.