The graphene revolution

Of all the experimental wonder materials being fashioned for the next great technological leap, there is none more exciting than graphene, a super-strong, super-light, almost invisible honeycomb of carbon, no more than an atom thick.

add_main_imageThis week, three separate studies—by teams in the US, China and Austria—published in the journal Nature Photonics described how graphene could be used to give critical components in existing silicon-based computer chips a steroidal boost, speeding them up and cutting their power consumption. This could be the basis for a new era of high-speed computing, perhaps with ultra-fast chips to entirely replace silicon.

Discoveries around graphene are weekly affairs. Thousands of papers have been written and hundreds of patent applications submitted since Andre Geim and Kostya Novoselov, Russian émigrés at the University of Manchester in the UK were awarded the 2010 Nobel prize for creating graphene.NextMAds

At a time when scientists believed a material so thin could never hold together, Geim (the only Nobel winner to also win the Ig Nobel prize for non-serious science, in this case using magnets to levitate a frog) and Novoselov used simple scotch tape—sticking it on graphite, the material of pencils—to rip out a one-atom-thick layer of graphene.

The clamour for graphene is easy to explain. It is 100 times stronger than the strongest steel, yet almost completely transparent because it is ultra-thin. The Nobel prize committee, in its citation, said a sq. m hammock of gossamer-thin graphene tied to two trees could support a 4kg cat—and weigh 0.77mg, no more than one of the cat’s whiskers.

Graphene could create super-fast telecommunications and electronics, and when mixed with plastic and other materials, create new kinds of light, flexible and strong things, from planes to tennis rackets to touch screens.

It is appropriate that graphene is a form of carbon, an elemental building block of life on Earth—the basis for everything from DNA to oil. In its purest form, carbon has few uses, other than pencils, diamonds and drill bits. Graphene is the third sibling of what is called “new carbon”, the other two being football-shaped fullerenes—dubbed “buckyballs”—and carbon nanotubes.

“In fairy tales, the third place is often the best,” said a 2011 article in the journal Nature. “It’s usually the third casket that contains the treasure, and the third child who finds fame and fortune. And so it may be for graphene.”

To be sure, similar excitement surrounded the discovery in 1985 of fullerenes and creation in 1991 of nanotubes. The hope was their exotic properties would lead to new products, drugs and materials. Much of that hype dissipated, though vigorous research continues and some incremental nanotube applications, such as thin films for conducting energy and reinforced materials for planes and cars, are close to commercialization.sixthMAds

With the sobering experience of buckyballs and nanotubes behind them, manufacturers are clearer about how graphene might be taken to market. All manner of companies, from Samsung to Boeing, are exploring applications of graphene. A handful of small companies are almost ready with graphene-based products related to more efficient batteries and printed electronic circuits.

Despite the excitement, these are early days for graphene. It is worthwhile recalling that the first silicon transistor was invented in 1948. The first product to use such a transistor rolled out four years later, a hearing aid. Intel, the company that used silicon breakthroughs to mass produce the silicon chips that power modern technology, was created only in 1968.

Electronics based on silicon have a head start of decades. Graphene might be where silicon was in the 1950s, except that with the hastened pace of technological developments and the demands made of modern companies to be lighter, faster and stronger, we could expect quicker results.

The great promise of graphene in electronics and telecommunication lies in its use in last-millimetre technology, so to say. Fibre optic cables shuttle the world’s data using beams of light, but inside the silicon chip, old-generation copper wires predominate, slowing and heating up computers. There are many problems to solve, one of them being that graphene conducts signals so well that it can’t be stopped; think of a light bulb that cannot be switched off. Many teams are working on solving such problems.

Although there are other materials competing to replace copper and silicon, graphene appears to be a leading contender, not just because of its physical properties but, equally, because it may be relatively cheap and easy to produce. Its raw material, graphite, can cost less than $5 per kg.

The three groups that announced this week’s advances in graphene produced the material by hand. Many teams are trying to create a process for this wonder product. Anything that is an atom thick will not be easy to mass produce. Of course, you only need recall what Geim and Novoselov did with a scotch tape.

Samar Halarnkar is a Bangalore-based journalist. This is a fortnightly column that explores the cutting edge of science and technology. Comments are welcome at frontiermail@livemint.com.

To read Samar Halarnkar’s previous columns, go to www.livemint.com/frontiermail--