Want to win a Nobel prize while discovering a material that’s cheap, transparent, flexible but resistent, and an astonishing electric conductor? Grab a pencil and a roll of adhesive tape. I’m serious.
Pencil leads are made of graphite, a form of carbon made of layers of atoms organized in hexagonal cells, like a bee hive. Atoms on the same layer stick together tightly, but are much more loosely attached to the next layer. So, when we write, a few layers peel off the tip and go to the paper.
If graphite sounds like graphene, it’s because they’re pretty much the same thing. Andre Geim and Konstan Novoselov (who won the Nobel prize for their discovery) created graphene for the first time by repeatedly sticking tape to graphite and ripping it off. Every time a few layers would stick to the tape, until what was left was a single atom thick.
Because it’s so thin, graphene has only the properties of the carbon layer. Without interference from the other layers, it doesn’t behave like a pencil’s graphite anymore. Instead, it supercharges its properties.
For example, each atom is somewhat willing to part with four of its electrons. In a graphene sheet, the atom only has three neighbors to share electrons with, so one is pretty much free to leave and roam around. This makes graphene extremely conductive. If the electrons were busy sticking to other layers (as in graphite) the material would conduct less.
Being so thin, graphene is rather transparent, and very light. But it’s also spectacularly strong (more than steel), thanks to the strong bonds between its atoms.
Thanks to its fantastic properties, graphene is the protagonist of countless works in material science. Electronic devices cannot ask for better than a very conductive material, that doesn’t break and can be used for touch screens.
Making big enough sheets isn’t easy, though, so it still takes a while to have industrial-scale use of graphene.
And if you still want that Nobel prize, I’m afraid the sticky tape and pencil way is taken.
If you want more
- Nature has an interesting comment on the challenges facing the commercialization of graphene