London: New ultra-thin, patterned graphene sheets developed by scientists could enable future applications such as "smart wallpaper" generating electricity from waste light or heat, and power a host of applications within the growing "internet of things," says a new study.
A form of carbon just one atom thick, graphene is very strong and an excellent electronic material, but is inefficient for optical applications as it absorbs only 2.3 percent of the light falling on it. However using a new technique, scientists enhanced its light absorption by 90 percent.
In the study, published recently in Science Advances, researchers from Britain's University of Surrey, inspired by nature, used nanotexturing to create the most light-absorbent graphene for its weight, to date.
"Nature has evolved simple yet powerful adaptations, from which we have taken inspiration in order to answer challenges of future technologies.
"Moths' eyes have microscopic patterning that allows them to see in the dimmest conditions. These work by channelling light towards the middle of the eye, with the added benefit of eliminating reflections, which would otherwise alert predators of their location," said professor Ravi Silva, head of the Advanced Technology Institute at Surrey.
"We used the same technique to make an amazingly thin, efficient, light-absorbent material by patterning graphene in a similar fashion," he added.
Smart applications of this ultra-thin graphene could be more efficient solar cells and new types of sensors and energy harvesters.
"Solar cells coated with this material would be able to harvest very dim light. Installed indoors, as part of future 'smart wallpaper' or 'smart windows', this material could generate electricity from waste light or heat, powering a numerous array of smart applications. New types of sensors and energy harvesters connected through the internet of things would also benefit from this type of coating," said Silva.
"The next step is to incorporate this material in a variety of existing and emerging technologies," he said.