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The wonder stuff that could change the world: Graphene is so strong a sheet of it as thin as clingfilm could support an elephant
It is tougher than diamond, but stretches like rubber. It is virtually invisible, conducts electricity and heat better than any copper wire and weighs next to nothing. Meet graphene — an astonishing new material which could revolutionise almost every part of our lives.
Some researchers claim it’s the most important substance to be created since the first synthetic plastic more than 100 years ago.
If it lives up to its promise, it could lead to mobile phones that you roll up and put behind your ear, high definition televisions as thin as wallpaper, and bendy electronic newspapers that readers could fold away into a tiny square.
It could transform medicine, and replace silicon as the raw material used to make computer chips.
The ‘miracle material’ was discovered in Britain just seven years ago, and the buzz around it is extraordinary.
Last year, it won two Manchester University scientists the Nobel Prize for physics, and this week Chancellor George Osborne pledged £50 million towards developing technologies based on the super-strong substance.
In terms of its economics, one of the most exciting parts of the graphene story is its cost. Normally when scientists develop a new wonder material, the price is eye-wateringly high.
But graphene is made by chemically processing graphite — the cheap material in the ‘lead’ of pencils. Every few months researchers come up with new, cheaper ways of mass producing graphene, so that some experts believe it could eventually cost less than £4 per pound.
But is graphene really the wonder stuff of the 21st century?
For a material with so much promise, it has an incredibly simple chemical structure. A sheet of graphene is just a single layer of carbon atoms, locked together in a strongly-bonded honeycomb pattern.
Pledge: George Osborne, pictured visiting the University of Manchester lab where graphene is being researched, has said £50m will be set aside to help with development of technologies based on the susbstance
That makes it the thinnest material ever made. You would need to stack three million graphene sheets on top of each other to get a pile one milimetre high. It is also the strongest substance known to mankind — 200 times stronger than steel and several times tougher than diamond.
A sheet of graphene as thin as clingfilm could hold the weight of an elephant. In fact, according to one calculation, an elephant would need to balance precariously on the end of a pencil to break through that same sheet.
Despite its strength, it is extremely flexible and can be stretched by 20 per cent without any damage.
It is also a superb conductor of electricity — far better than copper, traditionally used for wiring — and is the best conductor of heat on the planet.
But perhaps the most remarkable feature of graphene is where it comes from. Graphene is made from graphite, a plentiful grey mineral mostly mined in Chile, India and Canada.
A pencil lead is made up of many millions of layers of graphene. These layers are held together only weakly — which is why they slide off each other when a pencil is moved across the page.
Graphene was first isolated by Professors Konstantin Novoselov and Andrew Geim at Manchester University in 2004. The pair used sticky tape to strip away thin flakes of graphite, then attached it to a silicon plate which allowed the researchers to identify the tiny layers through a microscope.
Discovery: Professors Andre Geim, left, and Dr Konstantin Novoselov first isolated graphene in 2004. They later won the Nobel Prize for Physics last year
Russian-born Prof Novoselov, 37, believes graphene could change everything from electronics to computers.
‘I don’t think it has been over-hyped,’ he said. ‘It has attracted a lot of attention because it is so simple — it is the thinnest possible matter — and yet it has so many unique properties.
‘There are hundreds of properties which are unique or superior to other materials. Because it is only one atom thick it is quite transparent — not many materials that can conduct electricity which are transparent.’
Its discovery has triggered a boom for material science. Last year, there were 3,000 research papers on its properties, and 400 patent applications.
The electronics industry is convinced graphene will lead to gadgets that make the iPhone and Kindle seem like toys from the age of steam trains.
Modern touch-sensitive screens use indium tin oxide — a substance that is transparent but which carries electrical currents. But indium tin oxide is expensive, and gadgets made from it shatter or crack easily when dropped. Replacing indium tin oxide with graphene-based compounds could allow for flexible, paper-thin computer and television screens. South Korean researchers have created a 25in flexible touch-screen using graphene.
Ancient history: If the development of graphene is successful it will make the iPad and Kindle seem like toys from the age of the steam train
Imagine reading your Daily Mail on a sheet of electric paper. Tapping a button on the corner could instantly update the contents or move to the next page. Once you’ve finished reading the paper, it could be folded up and used afresh tomorrow.
Other researchers are looking at many ways of using graphene in medicine. It is also being touted as an alternative to the carbon-fibre bodywork of boats and bikes. Graphene in tyres could make them stronger.
Some even claim it will replace the silicon in computer chips. In the future, a graphene credit card could store as much information as today’s computers.
‘We are talking of a number of unique properties combined in one material which probably hasn’t happened before,’ said Prof Novoselov. ‘You might want to compare it to plastic. But graphene is as versatile as all the plastics put together.
‘It’s a big claim, but it’s not bold. That’s exactly why there are so many researchers working on it.’
Dr Sue Mossman, curator of materials at the Science Museum in London, says graphene has parallels with Bakelite — the first man-made plastic, invented in 1907.
Resistant to heat and chemicals, and an excellent electrical insulator, Bakelite easily made electric plugs, radios, cameras and telephones.
‘Bakelite was the material of its time. Is this the material of our times?’ she says. ‘Historically we have been really good at invention in this country, but we’ve been really bad at capitalising on it.’
If graphene isn’t to go the same way as other great British inventions which were never properly exploited commercially at home — such as polythene and carbon fibre — it will need massive investment in research and development.
Core material: Graphene comes from a base material of graphite and is so thin that three millions sheets of the substance would be needed to make a layer 1mm thick
That’s why the Government’s move to support its development in the UK got a warm round of applause at the Conservative Party conference.
But compared to the investment in graphene in America and Asia, the £50 million promised by the Chancellor is negligible. South Korea is investing £195million into the technology. The European Commission is expected to invest one billion euros into graphene in the next ten years.
Yet despite the flurry of excitement, many researchers doubt graphene can live up to such high expectations.
It wouldn’t be the first wonder material that failed to deliver. In 1985 another form of carbon, called fullerenes or buckyballs, was hailed as the revolutionary new material of the era. Despite the hype, there has yet to be a major practical application.
And there are already some problems with using graphene. It is so good at conducting electricity that turning it into devices like transistors — which control the flow of electrical currents, so need to be able to stop electricity flowing through them — has so far proved problematic.
Earlier this year computer company IBM admitted that it was ‘difficult to imagine’ graphene replacing silicon in computer chips.
And sceptics point out that most new materials — such as carbon-fibre — take 20 years from invention before they can be used commercial use.
You might think from all the hype, that the road to a great graphene revolution has already been mapped out.
But its future is far from certain. In fact it’s barely been pencilled out in rough.