Graphene ‘Wonder Material’ Can Now Be Made Using TRASH


Graphene is cool stuff. The single-atom thick layer of carbon has
a number of properties that make it almost endlessly useful. Because of all the neat tricks it can do,
it’s popularly dubbed a “wonder material,” but over a decade and a half after it was
first isolated, the only thing I’m wondering is: where it is?! Turns out the stuff is really hard to make
in useful quantities, but a recent breakthrough from researchers at Rice University promises
to make large amounts of graphene in a flash from your trash. For those of you watching your first episode
of Seeker ever, (congrats, welcome, hi) graphene looks like this. This is what I call a graph-ic. Anyway, it’s not much to look at—it kind
of resembles chicken wire. But this honeycomb lattice of carbon can do
some amazing things. It is one of the thinnest, strongest, and
most conductive materials we have ever discovered. Its strength can be used to make other materials
stronger. Its amazing conductivity could help us make
energy-dense batteries or efficient heat sinks. Its flexibility could make wearable electronics
and bendable displays. You get the idea—do I really need to keep
going? Which is why it is so frustrating that it’s
so hard to make in large amounts. Ironic, considering it was first isolated
by applying a piece of sticky tape like you might have in your home to a block of graphite
and peeling it off, then resticking and peeling the tape apart until you’re left with thin
flakes. It’s like it’s taunting us. But there’s a reason we don’t have armies
of people just peeling tape apart. The graphene that this technique produces
is still a few layers thick, and we’re after that single-atom-thick goodness. As of right now, the prevailing methods to
achieve that usually involve assembling it on sheets of copper, then using plastics and
chemicals to get it off. But the process is slow, expensive and not
environmentally friendly. A piece of 60mm x 40 mm monolayer graphene
on copper will cost you about $172. But what if we’re overthinking this? What if we could just take any old carbon
source and zap it to make graphene? As far as I can tell, that’s basically the
line of thinking the researchers from Rice University followed. The process they developed involves charging
up high-voltage capacitors with electricity, then unleashing it all at once into just about
any carbon-containing material. Anything from coal, which is basically all
carbon to start with, to plastics, to food waste. The current passes through the target material,
heating it to over 3,000 Kelvin and breaking every carbon-to-carbon bond in the process. The non-carbon elements sublime out, while
the carbon atoms rearrange themselves as graphene. Excess energy is dispersed as light, so researchers
dubbed the product “flash graphene.” The change can take as little as ten milliseconds. Not only does this produce a gram of graphene
quickly and cheaply; it also makes a particular kind of graphene called turbostratic graphene. Unlike A-B stacked graphene, which has orderly
layers that are hard to pry apart, the layers of turbostratic graphene have no ordered alignment. This means they can be easily separated using
solvents or inside composite materials. Now, this process doesn’t make large sheets
of graphene, just small flakes. So it may not be the breakthrough that leads
to flexible screens you can put on a T-shirt. But it still has some very useful—albeit
less flashy—applications. The researchers envision flash graphene being
added to concrete, and estimate that just a fraction of a percent of graphene added
in could boost cement’s strength by 35%. That translates to less building material
needed, saving costs and lessening the environmental impact. Flash graphene could be an ecological double
win, because it can be made with recycled plastic or food waste, or it could be an alternative
use for cheap coal that doesn’t involve burning it and releasing CO2. The Department of Energy thinks turning coal
into graphene looks promising, and are funding the research with the goal of producing a
kilogram of flash graphene a day within two years. I know we’re all clamoring for graphene
to take the world by storm, but the reality is that it’ll take incremental steps like
this to bring this wonder material into our daily lives. It’s already showing up in places that are
hard to spot, like inside headphones and the coating of motorcycle helmets. Now thanks to this new work, it may soon show
up in our buildings, too. And the only way you might be able to tell
is if you measured the thickness of the walls, or noticed there was suddenly a lot less plastic
and banana peels lying around. One of the lead researchers from Rice, James
Tour, started experimenting with making graphene out of odd sources because of a bet in 2011
when a colleague challenged him to make it out of, among other things, cockroaches and
dog poop. Thanks for watching, if you like this video
you can check out more like it, like this one on angled graphene, and subscribe for
even more videos. I’ll see you next time on Seeker.