October 11, 2012
Roadmap Showcases Potential Of Graphene
April Flowers for redOrbit.com — Your University Online
Graphene is the world's thinnest, strongest, and most conductive material. It is made of pure carbon, and only one atom thick. Nobel prizewinner Professor Kostya Novoselov and an international team have created a "Graphene Roadmap" to show what the material could truly achieve.
One area the team identifies as key is in touchscreen applications for devices like Apple's iPad, which uses indium tin oxide. Graphene has superior mechanical flexibility and chemical durability, meaning that graphene touchscreen devices would prove far more enduring and open a way for flexible devices. The team estimates the first graphene touchscreen devices could reach the market within three to five years. They warn that graphene will only reach its full potential in flexible electronics applications.
Another possible prototype application that should be available by 2015 is rollable e-paper. Graphene's flexibility proves ideal for fold-up electronic sheets, which could revolutionize electronics.
The report claims that the timescales for different applications varies greatly depending on the quality of graphene required. For example, devices including photo-detectors, high-speed wireless communications and THz generators used in medical imaging and security devices will probably not be available until 2020, according to the report. Anticancer drugs and graphene replacements for silicon are unlikely to become available until closer to 2030.
The report lists and describes the different methods of graphene production, most of which were developed from the sticky tape method pioneered by Novoselov and Geim.
The three main methods for production include:
1) Liquid phase and thermal exfoliation, which is the process of exposing graphite to a solvent which splits it into individual flakes of graphene. This method is perfect for energy applications (batteries and supercapacitors), as well as graphene paints and inks for products such as printed electronics, smart windows and electromagnetic shielding. This process of graphene production also adds functionality to composite materials (extra strength, conductivity, moisture barrier).
2) Chemical Vapor Deposition, which is the process of growing graphene films on copper foils, for use in flexible and transparent electronics applications and photonics.
3) Synthesis on Silicon Carbide, which involves growing graphene on either the silicon or carbon faces of silicon carbide. This can result in very high quality graphene with excellently formed crystals and is perfect for high-frequency transistors.
Professor Novoselov noted that "graphene has a potential to revolutionize many aspects of our lives simultaneously. Some applications might appear within a few years already and some still require years of hard work. Different applications require different grades of graphene and those which use the lowest grade will be the first to appear, probably as soon as in a few years. Those which require the highest quality may well take decades."
"Because the developments in the last few years were truly explosive, graphene's prospects continue to rapidly improve. Graphene is a unique crystal in a sense that it has singlehandedly usurped quite a number of superior properties: from mechanical to electronic. This suggests that its full power will only be realized in novel applications, which are designed specifically with this material in mind, rather than when it is called to substitute other materials in existing applications. "
"One thing is certain — scientists and engineers will continue looking into prospects offered by graphene and, along the way, many more ideas for new applications are likely to emerge."
Professor Volodya Falko of Lancaster University, co-author of this new study, says, "By our paper, we aim to raise awareness of engineers, innovators, and entrepreneurs to the enormous potential of graphene to improve the existing technologies and to generate new products. To mention, in some countries, including Korea, Poland and the UK national funding agencies already run multi-million engineering-led research programs aiming at commercialization of graphene at a large scale."