Graphene is traditionally inefficient at light absorption. To combat this, the team used the nano-patterning to localise light into the narrow spaces between the textured parts of the surface, enhancing the amount of light absorbed by the material by about 90%.
Professor Ravi Silva, head of the ATI, explained: “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. We have used the same technique to make an amazingly thin, efficient, light-absorbent material by patterning graphene in a similar fashion.”
Dr José Anguita of the University of Surrey added: “Typically, a graphene sheet would have 2 to 3% light absorption. Using this method, our ultrathin coating of nanotextured few-layer graphene absorbs 95% of incident light across a broad spectrum, from the UV to the infrared.”
While the Surrey team developed the technology in cooperation with BAE Systems for infrared imaging in opto-MEMs devices, the next is to incorporate this material into a variety of existing and emerging technologies. The team will also work with Surrey’s Graphene Centre to look for industry partners to exploit this technology.
