Graphene is a derivatve of graphite, the lead found in pencils. Graphite is comprised of loosely bonded layers of carbon atoms and Graphene takes those atoms and tightly binds them into hexagons one layer thick. The theory of graphene has been around for some time, but in 2004, two Manchester University scientists, Andre Geim and Konstantin Novoselov, along with others, proved that single layers of graphene could be produced. This achievement won the Nobel Prize for Physics in 2010.
Graphene has many possible uses including replacing silicon in transistors and inert coatings. IBM and Samsung have been investing in graphene research for the speed capabilities of the transistors. Currently, IBM has created a 150 GHz transistor, compared to the fastest silicon transistor at 40 GHz. Graphene is also fairly resistant to many powerful acids and alkalis, and as a transparent material, could be used as a protective coating.
“Researchers at Rice University in Texas have found a way to synthesize graphene using table sugar, giving the material impeccable green credentials. In the same state, engineers at the University of Texas have even discovered that by replacing the carbon used in ultra-capacitors with graphene, it’s possible to store double the amount of energy. That in itself could revolutionize the renewable energy industry that is currently looking for a new way to store the energy produced by its burgeoning solar and wind farms. If the so-called “smart grid” is to prove successful, a way to store energy for when it’s not sunny or windy is essential.”
Of course, no product is without a set of issues. One major one is that graphene does not have a band gap, which means it will never stop conducting electricity. With silicon, it is possible to switch the material to an “off” position; therefore the replacement of silicon by graphene is not an immediate possibility.
Also, though the material is “stronger than steel” in a mirco sense, it has currently not been tested at a more macro level by producing a larger sample on par with building materials. This is not to discount the strength of the material, but don’t expect to soon be able to go out and buy graphene beams to replace your steel.
One other issue with the material is the fact that the properties of the material depend on the fact that it consists of a single layer of carbon atoms. When more then one layer is present, the attraction forces between the layers causes them to stick together and compromise the material properties. However, new developments in graphene research have just been published. Physicists at Linköping University have determined that one solution to this problem is to add an atomic layer of hydrogen between the layers of graphene. Hydrogen at a given concentration affects the atomic Van der Waals forces. Van der Waals forces are the attractive or repulsive forces between molecules. In the case of graphene, the forces attract, but with the hydrogen interrupting, the forces reverse and the layers repulse each other and float a few nanometers apart. This new development creates the possibility for more uses for the material including:
“Storage of hydrogen as vehicle fuel
Creation of a single graphene sheet by peeling them from a pile that has grown on a substrate of silicon carbide; a method developed at Linköping University
Repulsive forces are ideal for the manufacture of friction-free components on a Nano scale, for example, robots and sensors for medical purposes”