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Picture this:
You were thrown into a dingy room and told "You can't leave until you have created the
thinnest material known
to man."
Not only that, it must also be the strongest,
the best thermal conductor,
and as good at conducting electricity as copper.
I know, it sounds hopeless.
But luckily,
you know something about nanotechnology.
You know, really really tiny devices and materials that are less than a hundred nanometres
in size.
Of course, I don't have to tell you a nanometre is a billionth of a meter.
That's roughly the size of ten atoms.
But how do you create something that tiny?
It's time to embrace your inner MacGyver.
You're gonna need a pencil, some scotch tape
and a healthy dose of elbow grease.
A pencil contains not lead but graphite, which consists of sheets of carbon in a
hexagonal lattice.
When you write, layers of graphite slide off the tip of the pencil and stick to the
paper.
Usually, many layers are stacked on top of each other
but once in a while you get a single layer of carbon atoms.
And this is called
'graphene'.
In 2004, Andre Geim and Konstantin Novoselov created
graphene using nothing but graphite and scotch tape.
They placed a graphite flake onto the tape,
folded it in two and then cleaved the flake in half.
They repeated this procedure a number of times and then studied the resulting fragments.
To their astonishment
they found some of the pieces were only a single atom thick.
This was particularly unexpected because it was thought a single layer of
graphite would not be chemically stable,
especially at room temperature.
Graphene conducts electrons faster than any other substance at room temperature.
This is because of the extraordinarily high quality of the graphene lattice.
Scientists are yet to find a single atom out of place in graphene.
Since the electrons aren't scattered by defects in the lattice,
they go so fast
that Einstein's relativity must be used to understand their motion.
And this perfect lattice is created by the very strong yet flexible bonds between
carbon atoms -
making the substance bendable
but harder than diamond.
Graphene is incredibly strong -
if you could balance an elephant on a pencil and
support the pencil on graphene,
the graphene wouldn't break.
Of course the pencil would.
For their discovery, Geim and Novoselov were awarded the Nobel Prize
for physics in 2010.
And this is only the beginning for Graphene.
Scientists are hard at work exploiting its unique properties to create:
Thin, transparent, flexible touch screens;
Smaller, faster, more energy efficient computers;
Tough composite materials;
And more efficient solar cells.
And now consider: this is only one aspect of nanotechnology,
so in order to think big
you need first consider
the very small.