The super-material graphene has been in the news again: this time, as a rather fine method of distilling vodka…
Extraordinary stories about graphene crop up with serious regularity, which is perhaps no surprise when you consider the rather unusual method employed to discover it. In 2004, Professor Sir Andre Geim and Konstantin Novoselov managed to isolate graphene flakes, by employing a low tech method completely at odds with the incredibly hi-tech possibilities of the material – using simple adhesive tape to strip it from graphite.
The pair won the 2010 Nobel Prize in physics for their pioneering work, but the story doesn’t end there – far from it. In fact, graphene, which is in essence, a single ‘sheet’ of graphite, has been found to be a material of such impressive qualities that it could be classed as the strutting peacock of the sub-atomic world. A quick look at the graphene CV reveals:
* it is thin – very thin. It would take three million sheets of it to make a one millimetre thick sheet of graphite.
* It is virtually invisible
* electricity flows through it faster than any other material.
* it is the best conductor of heat on the planet
* it is 200 times stronger than steel and several times tougher than diamond
* it is highly flexible and can be stretched like rubber.
* its uses are incredibly varied and major companies and government agencies are falling over themselves to patent new devices and technologies - researchers at Samsung and Sungkyunkwan University, in Korea, recently developed a 63-centimeter-wide flexible touch-screen from the material and George Osbourne recently promised a £50 million investment to create a UK graphene research hub.
That’s what we know already, but last week, Geim and his University of Manchester team published some more interesting research results. They found graphene to be impermeable by any liquid or gas, including the notoriously difficult to trap helium, but then they discovered an even bigger graphene surprise; membranes of graphene oxide allowed ‘unimpeded permeation of water’.
The discovery led to the team trying to do something a little different. “Just for a laugh, we sealed a bottle of vodka with our membranes and found that the distilled solution became stronger and stronger with time. Neither of us drinks vodka but it was great fun to do the experiment”, said Dr Rahul Nair to the Press Association , who headed up the experimental study. You can check the research in full here.
Alcohol distillation aside, the researchers aren’t really sure of where this new feature of graphene could lead to at the moment. However, Professor Sir Gein’s comment on the discovery is more than intriguing; ‘the properties are so unusual that it is hard to imagine that they cannot find some use in the design of filtration, separation or barrier membranes and for selective removal of water.’
Graphene’s ability to clear oil from water has already been documented, but if you can imagine, without the constraints of current technology, the potential of filtering sea water or dirty water to fresh or clean water, for example, then this could be yet another incredibly important property of this truly amazing material…