If these claims seem extraordinary, then so too is the material which could make them possible. Graphene is made of a single element, carbon, arranged in a flat, unchanging crystal pattern that looks like chicken wire. Although it may sound rare and complex it is simply very thin layers of graphite – the same as found in a common pencil. In fact it's now realised that almost every stroke of a pencil leaves fragments of graphene in the shining grey trace on the paper.
It was discovered in 2004 by Russian-born physicist Andre Geim, who won a Nobel Prize for Physics together with Konstantin Novoselov for their work in 2010. Graphene could be the latest addition to a long line of material advances that have made our mobile phones possible. Think about the silicon slivers into which millions of electronic components can be etched; the lithium-ion batteries that pack a day or more's worth of charge, and the low-energy light emitting diodes that can screen video in vivid colours.
What makes graphene remarkable is its ability to take on any of these roles. And what is more, it can conduct electricity better than copper, has strength greater than steel and also shows extraordinary elasticity. Not only have thousands of scientific papers been published describing graphene's many aspects; over 7,000 patents have been issued, many on technologies that could end up in mobile phones. No wonder electronics giant Samsung has invested huge sums into developing graphene as a material for screens and electronics; Nokia is backing a billion-euro project to exploit the carbon material and IBM has started a formidable research effort.
So far, the smart-phone screen is where most attention has been paid publicly. The industry currently depends on a compound called indium-tin-oxide. And it's the little-known metal indium that's the problem. Demand has grown massively with the development of flat screens with global production quadrupling in the two decades to 2008. Since then production has levelled off, but the price for the metal peaked at $720 for a kilo in 2011, and the industry is concerned about the long-term security of supply. To further compound the problem indium-tin-oxide is a brittle material, making it difficult to work with.
Graphene is composed of a sheet of carbon atoms arranged in a honeycomb crystal lattice. The material which is both flexible and strong is cheap, see-through and critically is electrically conductive. That makes it ideal for the flat-screen displays used on smart phones that need electricity to power the optical elements, and to respond to the user touch.
Its transparency, thickness, flexibility and ability to conduct electricity make it potentially useful for building future touch screens. Samsung and Nokia have already shown off concepts for "bendy" phones – such as the newly unveiled Samsung "YOUM" screen or the Nokia morph concept -with shapes unlike anything seen today. Although less extreme versions of some of these concepts may first be brought to market using more conventional technology, Nokia researchers believe that "graphene may well be one of the crucial elements of making Morph reality".
Although these kinds of concepts excite the imagination and show the possibilities of graphene, durability is where the greatest interest lies. What the industry really wants is a touch screen a user can stab thousands of times a day without fear of the electronics ever giving out. Again, that's what makes graphene so attractive. Of course it has to be cost effective, too. As recently as 2009, it was only possible to manufacture samples of graphene that were a few centimetres across. But in 2010, Samsung-backed researchers at Sungkyunkwan University in South Korea showed it was possible to create roll of metres of the material, and demonstrated it on touch-sensitive tablet screens. And since then Sony has built a machine that can create rolls of the material 100m long – claimed to be the largest sheets in the world.
Its ability to conducts electrons faster than silicon means graphene could also be used to build a new generation of electronics, such as the transistor shown above. Reading the technical papers exploring its potential, you are immediately struck by the caution expressed by the scientists doing the studies. The stumbling blocks are many. And the electronics industry is ruthlessly Darwinian. We have our mobile phones because the mobile industry and the silicon industry can turn out precision-engineered components by the bucket load, and any competing technology has to be robust in the fabrication plant and in the product. And it has to be cheap. Graphene is still yet to be tested in this environment. Nor is graphene the only new material on the block; nano-wires and plastic electronics are among the competition being explored. But, whatever the current issues with graphene, it has to be remembered that the first attempts to make electronic components out of silicon five decades back were a complete flop. History now shows that was only a temporary setback. The ability to do so much with a single material is what made silicon (through the notion of the integrated circuit) such a success in the end.
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And progress with graphene has been unexpectedly rapid – the successes of the Samsung roll-to-roll production and the IBM circuit took those in the business by surprise. More surprises are surely around the corner. As Nokia researchers have cautiously said "graphene holds tremendous promise". Whether it will deliver on these promises, only time will tell.