Graphene – the new super material

written by Roy Rosser, Ph.D. Patent Agent

Is it Atomic Chicken Wire?
Is it the Usain Bolt of Crystals?
Yes, it’s the new Super Material Graphene

Since 2010, when the discoverers of graphene were awarded the Nobel Prize for Physics, this latest miracle material has had Angel Investors leaping tall buildings – and the Patent Office working overtime.

In 2009, only 32 published patent applications had graphene in the title. In 2010, that jumped to 130 and by 2012 it was 221 – and filings seem to be on track to exceed that in 2013. And it’s not just small-time lone-inventors. Big names like IBM, Samsung, Apple, Nokia and Head are all in on the land-grab, filing patents as fast as legal will let them.

So what is graphene? And why is Head – a well-known manufacturer of tennis rackets and skis -filing patents on a material that has the electronic giants in a frenzy? I’ll get to that later.

Meanwhile, many of the remarkable properties of grapheme can be deduced from the titles of the patent applications. In addition to the many “how to make graphene”, many are oriented to specific uses of the material and include, but are not limited to, “graphene nano-electronic device fabrication”, “graphene solar cell”, “graphene chemical sensors”, graphene field effect transistors”, “graphene varactors” “graphene photo-detectors” and “graphene desalination”.

Graphene is simply carbon – but carbon arranged in a unique way – as a single, flat layer. Its bond structure may be imagined as a sheet of atomic-scale chicken wire. This unusual arrangement leads to some remarkable properties. Graphene turns out to be the best conductor of electricity yet discovered, with incredibly high electron mobility, even at room temperature – hence the interest in using it for electronics – and for some people describing it as the Usain Bolt of semi-conductor crystals. Theoretically, graphene-based electronics could provide devices that switch thousands of times faster than current devices.

Graphene is also a very good conductor of heat – hence the interest in using it both for deicing and heat dissipation.

It also has remarkable optical properties. Despite being a monolayer of atoms, a single layer of graphene absorbs a remarkable 2.7 % of incident light. This is low enough to make graphene potentially a very useful transparent electrode, useful in video displays, yet high enough to make it an interesting material for solar panels. The light absorption also saturates, i.e., it maxes out after which further

light is transmitted as if the material is transparent. This is a very useful property in controlling light, especially in lasers, where it may be useful as a “Q” switch.

Desalination? Graphene has the remarkable property of being porous to water, but screens out almost all other molecules, including Na+ and OH- molecules – so, potentially, a means to low cost desalination of sea water. Any trapped molecules significantly alter its electronic properties, allowing it to be used as a very sensitive chemical detector, especially when combined with other molecules, including DNA.

Graphene does have one major defect – it is a semi-conductor without a band gap. Without getting technical, this means that although it is a terrific conductor of electricity, no-one has yet found out how to turn off the flow of electrons through, which is needed to produce conventional transistors. So there is a huge hunt on for a way to achieve this – or to provide control circuits that don’t need this property.

And why is Head – maker of tennis rackets and skis – applying for patents for the use of graphene in sporting goods? They are claiming uses in all the usual suspects – tennis rackets, skis, ski boots, bike-helmets, etc. They have even started marketing a graphene-reinforced tennis racket. By embedding graphene into an epoxy matrix that is part of the racket build, the racket performance is claimed to be improved “being lighter yet more durable with having more proportional stiffness in different directions”. In preliminary promotional materials, Maria Sharapova reports increased precision and ease of use while Novak Djokovic calls his new graphite-reinforced racket his “secret weapon”.

Call me a skeptic, but I doubt if the flakes of graphene in the handle make much difference to the racket’s performance. Graphene is stronger than steel – but the flakes being used are probably too small to make much difference to the overall strength. I once took a long ski lift ride in the company of a VP from ski maker K2 and we had plenty of time to discuss ski construction. He revealed an open secret of the sports industry, which can be summed up as “put it inside, so you can put it on the outside”. What he meant was that manufacturers of sporting goods have a habit of incorporating the “material de jour” in a product, irrespective of what benefit it provides, so they can advertise it. So get ready for “graphene-reinforced skis, golf clubs, boots, helmets … etc., etc.

In summary: graphene is a new, cheap, relatively easy to manufacture material with a wide range of very interesting properties. A rare opportunity for innovators, entrepreneurs and salespeople. But if you think of some possible application, don’t hesitate. The graphene land grab is on, so don’t wait, especially in this new world of “First Inventor to File”. Get a provisional patent application to the USPTO ASAP – but then that’s what a patent agent would advise, isn’t it?