Edit: Editor’s Selection on ResearchBlogging!
Stop eating your cookie right now – put it down on the desk and save it. There are enough carbon atoms in it to make it worth more than your rapidly dwindling retirement account. In fact there are enough carbon atoms around you right now that – properly rearranged – to make you rich enough to retire immediately! Am I talking about transmuting carbon into gold? No – just rearranging them to make graphene! I’ve written briefly about graphene here before, and its wide variety of interesting properties and uses – so interesting that its discoverers were awarded the Nobel prize in physics last year. High quality graphene in bulk quantities is still fairly expensive to produce – until now that is.
A group of researchers at Rice University published in Nano Letters a method for creating high quality graphene from any source of carbon. Yes any source of carbon. Considering all organic material is primarily carbon based, this means that you can make graphene from nearly everything around you right now. Your half eaten sandwich, the fly buzzing around you, the wood in your desk… any source of carbon. In the paper they demonstrate using a number of materials, such as a cockroach leg and even some dog crap (I wonder which graduate student was tasked with retrieving that source of carbon…) to create graphene. The method is also surprisingly straight forward. The carbon source is placed on a thin piece of copper foil and heated up to 1000° Celsius under an atmosphere of hydrogen and argon. High quality Graphene is then deposited on the backside of the copper foil!
Why is graphene formed over some other form of carbon, like diamonds, or just the blackened soot you get when your burn your dinner? The soot or other “burned” products will not form because there is no oxygen available in the atmosphere when they heat the carbon source up. Thus the carbon cannot oxidize and “burn”. Also, it turns out graphene is the most stable form of elemental carbon, so when it is in graphene it is in the lowest energy state that carbon can be in. Sweet! They have not quite worked out the exact mechanisms of graphene formation yet so, some of this is speculation on my part.
Even better though is this short video where the researchers demonstrate to a troop of girl scouts how they can use a girl scout cookie to make graphene. They note that the going rate for a 2-inch square sheet of graphene is approximately $250, so accounting for all the carbon available in girl scout cookies , the typical box of shortbread transformed into graphene would be worth over $15 billion dollars – which certainly got some attention from the scouts in attendance! Here is the video – make sure to watch out for the expression on one of the scouts when the researcher tells her that the small amount of graphene they just made was worth a couple hundred dollars…
In conclusion: I might convert shortbread to graphene, but a a thin mint? I don’t think so.
Ruan, G., Sun, Z., Peng, Z., & Tour, J. (2011). Growth of Graphene from Food, Insects, and Waste ACS Nano DOI: 10.1021/nn202625c