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In a lab off of a shaft-like corridor below the University of Toronto’s old Lassonde Mining Building, PhD student Changhong Cao is employing some strikingly humble equipment: Scotch Tape.

Surrounded by a nuclear microscope and high-powered computers, the mechanical engineer uses the Christmas wrapping staple to peel off the top layers from a square of graphite the size of a Scrabble tile.

That’s the same sort of carbon-based graphite at the centre of every ordinary pencil you’ve ever used.

Then, repeatedly folding fresh segments of the tape over the captured graphite smudge, Cao peels off more and more of the carbon layers originally deposited on the sticky surface.

The resulting material — known as graphene — is the strongest on Earth and may now be on the cusp of transforming the world.

“It truly has remarkable potential,” Chandra Veer Singh, a materials scientist at U of T, says of the substance.

What graphene can do

That potential, many experts say, includes radical improvements to everything from touchscreens and computer chips to tennis rackets, window panes and solar panels.

Graphene is so thin it’s transparent. Yet it’s not only dozens of times stronger than steel, but possessed of a nearly miraculous array of electronic, thermal, anti-corrosive and chemically propitious properties.

No longer a ‘curiosity’

Mark Gallerneault is director of technology at a research lab in Kingston, Ont., that could soon launch Canada into the forefront of a coming graphene revolution.

“It’s going from a curiosity to something that people can actually work with,” says Gallernault, who works out of the Grafoid Global Technology Centre, just north of the city’s downtown.

Privately funded, Ottawa-based Grafoid opened the Kingston research and development plant last year in a lab abandoned by aluminum giant Alcan.

With a start-up investment from its sister company, the Canadian mining development firm Focus Graphite Inc., Grafoid raised more than $10 million in venture capital in 2013 before opening the R&D facility.

Though inhabiting a plant that retains a musty, 1970s décor, researchers here have an enthusiastic eye on the future — the very near future. By late spring, Gallerneault and his colleagues hope to demonstrate a unique process that could make graphene production commercially viable for a wide array of applications.

That would represent a huge leap for a country that has lagged many others in graphene development race.

The global contest is now dominated by China, the U.S. and South Korea, according to data from the U.K. Intellectual Property Office. Of some 8,400 graphene-related patent applications submitted as of February 2013, almost 6,000 originated from companies and educational institutions in those three countries.

A. Paul Gill, CEO of British Columbia’s Lomiko Metals Inc., lamented in a February media release that Canada has spent too much research energy on the oil industry while investment in graphene R&D has languished far behind the global competition.

“The EU (European Union) has put 5 billion Euros into graphene research,” said Gill, whose mineral development and exploration company is moving quickly into graphene applications.

Most Canadians “don’t even know about this Nobel-prize winning material.”

World’s thinnest

Graphene is surely one of the oddest of ducks in the material world.

At an ideal depth of one atom, it is the thinnest material on Earth, yet the strongest by weight ever measured.

And that strength is doubly puzzling given its graphite progenitor.

A grayish black mineral related to coal, graphite is made up of atom-thin layers of carbon configured in flat, honeycomb clusters and stacked one on top of the other like a deck of cards.

But as anyone who’s used a pencil can understand, these layers are weakly connected and easily shed — by merely rubbing the material across a sheet of paper for example. That greasy softness results from the feeble chemical bonds that bind one layer of graphite to another, Singh says.

Some 60 years ago, he says, scientists theorized that isolating a single layer of graphite would produce a material of profound strength. Indeed the covalent chemical bond, known as an sp2, that holds carbon together along each of graphite’s horizontal layers is the strongest in nature, he says.

“This (single, strong-bond) layer was known, but nobody could make it,” Singh says. “They thought it would not be stable at room temperature.”

Even before its discovery in Manchester, theorists had dubbed the material graphene.

“Essentially graphene is just taking graphite and peeling off one layer,” says U of T mechanical engineer Tobin Filleter, who runs the mining school lab and has worked with the material for six years.

In 2004, University of Manchester scientists Andre Geim and Konstantin Novoselov used tape to whittle down a chunk of their own graphite to a layer of carbon little more than one atom thick. The work helped win the two Russian-born researchers the Nobel Prize in Physics just six years later.

Geim and Novoselov’s work opened the research floodgates.

Though graphene could claim to be the mightiest of materials, however, much of the interest in it came to centre on properties other than its strength.

Stronger than steel

Graphene, depending on its purity, is anywhere from 40 to 100 times stronger than steel and a fraction of that metal’s weight.

But as Gallerneault points out, gossamer spiderwebs are much stronger and lighter than steel as well.

The obvious strength deficit in spiderwebs comes from the fact that they’re whisper-thin. This is a problem that graphene shares in spades. (At a thickness of less than one-millionth of a millimetre, it can only be visualized using powerful, atomic-force microscopes.)

So despite their relative super-strengths, both spiderwebs and graphene can be readily broken or punctured.

“You’re not going to think of a one-atom-thick (graphene) airplane fuselage,” says Singh, shooting down visions of Wonder Woman’s invisible jet come to life. Rather, he says, the material might be added in some configuration to other airframe materials to decrease a plane’s weight and boost its strength and durability.

Likewise, graphene might be infused into recycled plastics or other materials to create strong, corrosion-free rebar or girders for buildings and bridges.

“Basically (you) mix graphene inside some epoxy or some other kinds of things to add strength and lower weight,” Singh says.

The catch

The key drawback here is that no effective methods of engineering large sheets of graphene — or graphene composites — have yet been developed, Filleter says. Even the most advanced manufacturers have only managed to create affordable graphene materials that are a few square centimetres in area, he says.

“We know one sheet is extremely strong,” says Filleter. “But the challenge now is taking that one sheet and scaling it up to something like a bulletproof vest or a component for building a light airplane.”

Employing giant strips of Scotch Tape is not really an option, Filleter says. But, he says, electro-chemical strategies are being developed and improved to cleave graphene off of its parent mineral in larger segments.

Methods also exist to create graphene out of carbon-laden gases that build the material on surfaces under a stringent set of chemical and thermal conditions.

“We know it’s got these amazing properties, but that intermediate scale between one (small) graphene sheet and a real material, there’s still a big gap there,” Filleter says, “and it remains to be seen how well that gap can be addressed.”

Adding to the problem of scale, Singh says, current graphene production methods — while improving by the month — often create defects in the finished product, as do impurities in the parent graphite.

And the potential impact of these faults on the material’s mechanical might are still unknown and a main focus of research for Singh and his U of T colleagues.

More importantly, however, using graphene to add structural strength to products makes little commercial sense at the moment.

Because it is so vanishingly thin, Gallerneault says, substantial amounts of graphene would be required to markedly increase the physical brawn of bulk products like airplane or auto parts materials. And the problem with that is graphene is enormously expensive, running about $500 a gram.

“A kilogram of aerospace aluminum would cost you $10,” Gallerneault says. For graphene, “you’re talking $500,000 a kilogram.”

Complicated coating

Instead of trying to use the material in the large quantities that would be needed to strengthen products, the Kingston team is looking to stretch small amounts of graphene as far as it can go.

And that’s very far indeed.

Gallerneault says a cubic centimetre of graphene spread out in a one-atom-thick layer could cover an area a metre wide and a kilometere long.

“This is where it gets exciting for us,” he says.

He says his group is now capable of coating long tracts of materials with ultrathin graphene layers and that these lean laminates could add a host of properties to the treated surfaces.

A demonstration of the group’s large application process is scheduled in about four months.

“We know how to scale it up, absolutely,” Gallerneault says. Their plan is to be able to coat a sheet of aluminum about 30 centimetres wide and a few hundred metres long.

That scaled-up process will use graphene that’s been cleaved off of a refined graphite source using a secret, electro-chemical shearing process, rather than tape. This creates minuscule flakes of the supermaterial.

These sooty flakes, or platelets, are mixed with a precursor additive that chemically binds with the graphene particles’ carbon edges to keep them from reverting back into graphite — as they would tend to do.

The chemically stabilized graphene is then mixed into a liquid, tea-coloured solution, which can be sprayed though an electric field onto a host of materials in an even, ultrathin layer.

The precursor chemicals, also a trade secret, can then be removed, leaving a layer of pure graphene about one to three atoms thick. While pure graphene is one layer or atom in depth, it retains its various properties at thicknesses of up to 10 layers.

Back at the U of T lab, Cao finishes his tape-peeling labours and points to the nearly invisible carbon smudge at the top of the strip.

That transparent bit of “wonder material,” many scientists would say, is a window into a graphene future.

It’s a future drawn from the stuff at the tip of a pencil.