字幕列表 影片播放
-
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.