MONDAY, MAY 6, 2013
Paper-thin layers of graphene, sandwiched with other one-atom slices of materials, could provide the next solar coating for building exteriors, researchers say.
The world's thinnest, strongest and most conductive material, graphene has been the hub of much coating research since University of Manchester Nobel Laureates Professor Andre Geim and Professor Kostya Novoselov discovered the material in 2004.
Now, researchers at the University of Manchester and National University of Singapore have shown how building multi-layered heterostructures in a three-dimensional stack can produce electric energy to run entire buildings by sunlight absorbed by exposed walls.
Photos: University of Manchester |
Extremely thin layers of graphene, sandwiched with other one-atom-thick materials, can produce a multitude of unique properties, researchers found. |
This energy could be used at will to change the transparency and reflectivity of fixtures and windows, depending on environmental conditions, the researchers said.
Geim and Novoselov won the 2010 Nobel Prize in Physics for demonstrating the properties of graphene.
Anything's Possible
Novoselov said that the researchers were working on layering graphene to discover the resulting unique sets of properties.
"We are working on paints using this material as our next work, but that is further down the line," Novoselov told The Telegraph.
"We are excited about the new physics and new opportunities which are brought to us by heterostructures based on 2D atomic crystals," said Novoselov. "The library of available 2D crystals is already quite rich, covering a large parameter space."
Collectively, 2D crystals can demonstrate a wide range of properties, including being conductive, insulating, opaque and transparent. Every layer added creates new functions.
Professors Andrew Geim (left) and Kostya Novoselov won a 2010 Nobel Prize in Physics for discovering isolated graphene properties. |
"Such photoactive heterostructures add yet new possibilities, and pave the road for new types of experiments. As we create more and more complex heterostructures, so the functionalities of the devices will become richer, entering the realm of multifunctional devices," Novoselov said.
Making Solar Cells
The researchers expanded the functionality of these heterostructures to opoelectronics and photonics. They were able to create sensitive and efficient photovoltaic devices by combining graphene with monolayers of transition metal dichalcogenides (TMDC). These could potentially be used as ultrasensitive photodetectors or very efficient solar cells, researchers said.
Layers of TMDC were placed between two layers of graphene; the TMDC act as light absorbers and the graphene as a transparent conductive layer.
"Graphene is going to revolutionize the 21st century," says the University of Manchester, where research has been underway. |
"We were able to identify the ideal combination of materials: very photosensitive TMDC and optically transparent and conductive graphene, which collectively create a very efficient photovoltaic device," said Professor Antonio Castro Neto, director of the Graphene Research Centre at the National University of Singapore.
"We are sure that as research more into the area of 2D atomic crystals we will be able to identify more of such complimentary materials and create more complex heterostructures with multiple functionalities. This is really an open field, and we will explore it," Neto said.
Dr. Cinzia Casiraghi, from the University of Manchester, said, "Photosensitive heterostructures would open a way for other heterostructures with new functionalities. Also, in future we plan for cheaper and more efficient heterostructures for photovoltaic applications."
The research, "Strong light matter interactions in heterostructures of atomically thin films," was recently published in Science.
Powered Up
Other researchers are exploring the power potential of paints and coatings.
In March, coatings scientists at SPECIFIC (Sustainable Product Engineering Centre for Innovative Functional Coatings), an academic and industrial consortium led by Swansea University, announced that they were developing coatings for steel and glass that can turn new and existing buildings into power stations.
Tagged categories: Coatings Technology; Energy efficiency; Graphene; Research; Solar; Solar energy