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Ever since it was first discovered in 2004, graphene has been hailed as one of the most
important breakthroughs in materials since the plastics revolution more than a century
ago. A million times thinner than human hair, but 200 times stronger than steel. The early
predictions were that graphene would almost immediately enable the kinds of products and
technologies that we’re used to seeing in sci-fi movies. Cut to more than a decade and
a half later and that still hasn't happened. Not even close. With opinions split between
people overhyping graphene or calling it a massive disappointment, it’s time we got
to the truth of what is really happening with this so-called ‘wonder material’.
I’m Matt Ferrell … welcome to Undecided.
The hype around graphene is hardly surprising: a manmade substance with extraordinary properties.
It’s incredibly versatile and conductive, and is predicted to heavily disrupt industries
ranging from consumer electronics to aerospace for a while now. But even though progress
hasn’t been as fast as many would have hoped, researchers and product makers are now, at
last, beginning to make some headway.
Before we go on to what it can do, let’s first take a look at what graphene actually
is. To put it simply, it is fundamentally a single layer of graphite – the material
used to make pencil. But instead of having a three-dimensional crystalline structure
like graphite, graphene is two-dimensional, meaning it’s just one atom thick, with the
atoms arranged in a hexagonal lattice or honeycomb arrangement – a bit like chicken wire.
This structure is important because it allows each carbon atom to be covalently bonded to
three more around it, and the strength of these bonds is one of the main reasons why
graphene is so strong and stable. Another reason is because the atoms delocalise electrons
– meaning they can move around more freely – and this is what makes graphene so good
at conducting electricity and heat. In fact, it’s the most conductive material that we’ve
ever come across.
You’re probably thinking that the process of discovering this amazing material must
have been so mind-bogglingly complicated that us mere mortals couldn’t possibly comprehend
how it was done, but it was actually almost laughably simple. It was first isolated – aka
extracted from graphite – by two researchers, Andre Geim and Kostya Novoselov, at the University
of Manchester in the UK back in ‘04. How did they do it? By using sticky tape on a
piece of graphite and peeling it off, folding it and repeating the process over and over
again until they ended up with a single layer of graphene. Yep, it really was as easy as
that.
Although graphene was known to exist as far back as the 1940s, the discovery was widely
celebrated by the scientific community. Geim and Novoselov were awarded the Nobel Prize
for Physics in 2010 – and it immediately generated huge levels of excitement about
the material’s possibilities and potential uses in what many people hoped would be the
not too distant future. Expectations ranged from using it to replace silicon transistors
in electronics in the short term, all the way to building the immense cable or tether
that would be needed for a space elevator out of graphene in the future, although I
think we can all safely say that idea is a little way off for the time being.
So, what exactly has been holding it back? Why is the market not flooded with graphene-based
products when we’ve known how to make it for years? When graphene was first isolated
it was done in tiny amounts, and one of the main issues since then has been how to scale
up production of the material while ensuring the quality of graphene you end up is good
enough for the applications that it is intended for.
When the process of mass producing the material is – at least for now – very complex and
expensive, graphene products need to be significantly better than what’s already out there for
them to be considered worthwhile. If they’re not as good as the material they’re trying
to replace, or there’s very little noticeable difference, then why bother? For example,
silicone is an excellent material for use in electronics because of its special semiconducting
qualities, and many experts don’t see it as having many weaknesses. So if graphene
is going to knock it off its perch with the added cost and hassle needed to make it, then
it’ll need be a true game changer once the production methods have matured enough.
This was the problem with the first products that came out which included graphene in some
form. Many of the early entrepreneurs that were first to bring it to market ended up
disappointing their customers and investors with products that did technically incorporate
graphene, but didn’t sufficiently outperform what was already out there despite costing
considerably more. It was too soon; not enough follow-up research had been done at that stage
and it actually put a lot of people off graphene as a marketable material for a while.
Fortunately, researchers have been testing a range of new approaches to mass producing
graphene in recent years, and the results that we’re starting to see are very promising,
which is just as well, otherwise we’ll be needing a LOT of sticky tape to build that
space elevator.
One of the most popular and well-tested methods is a process called Chemical Vapor Deposition
or CVD, where graphene is effectively grown on a metallic surface, like copper, by combining
carbon-bearing gases inside a high-temperature reaction chamber. This leads to graphene being
deposited onto the metal, which can then be separated and transferred onto the substance
that needs enhancing. But doing it this way requires large amounts of energy, only yields
small amounts and relies on the use of harsh chemicals that can create a toxic by-product,
which is why others have gone in search of cleaner, cheaper and less power-hungry ways
of making graphene.
One new approach that has caught the eye of experts in the field is called flash graphene,
which has been described as a way of “turning trash into treasure.” This involves taking
virtually any material with high carbon content, such as used rubber tires and even some mixed
plastics, and converting it into graphene in an instant. The material is heated to 3,000
Kelvins – that’s approximately 5,000 degrees Fahrenheit – in just ten milliseconds. This
causes all of the carbon-to-carbon bonds to break and reconstruct as ‘turbostratic’
graphene, which has misaligned layers that are easier to separate. Its creators, a team
at Rice University in Houston, hope to produce a kilogram of graphene a day within two years,.
Others have been experimenting with new and emerging technologies, such as 3D printing,
to see whether they could be used for graphene production. Researchers at the Massachusetts
Institute of Technology successfully printed a number of 3D objects from graphene and compared
the results with conventional materials. Some of the pieces came out ten times stronger
than steel at one twentieth the mass. Scientists have also experimented with dispersing graphene
in water, which would allow it to be sprayed onto a surface as a coating. A team at Umeå
University in Sweden has created a thin film of highly conductive material from a dispersed
graphene solution. They are hopeful that this be used to create electrodes for supercapacitors,
which are advanced storage solutions that can charge much quicker and degrade less than
batteries, but can’t yet hold much energy.
While the plentiful supply of this wonder material remains a work in progress, we are
now finally starting to see the release of graphene-based products that actually do seem
to offer significant, tangible benefits over what their competitors have been making for
years with industry standard materials. A company called Real Graphene has created a
graphene-enhanced lithium battery that is thought to be on the verge of commercial use.
It can cut phone charging time from an hour and a half to 20 minutes, lasts three to five
times longer than conventional lithium batteries and generates less heat. This was achieved
by mixing graphene in with the lithium and introducing a composite layer of graphene.
Touch screens made with graphene are thought to be on the horizon as well. They could be
printed on thin plastic rather than glass, which would make them light, flexible, shatterproof
and therefore ideal for smartphones. Wearable electronics made using graphene that integrate
directly with fabric clothing are also believed to be achievable in the next few years.
Graphene’s high-strength and heat-conductive properties make it an excellent material for
a variety of protective equipment too. Italian motorcycle helmet manufacturer Momodesign
now offers a range of helmets with graphene-coated exterior shells. According to the company,
the presence of graphene improves the distribution of any impact force and dissipates heat faster
than conventional materials, increasing protection from thermal degradation.
Another Italian company, Italcementi, has proposed graphene-infused cement, which could
lead to houses that don’t require wiring as the building material is already highly
conductive on its own. Graphene’s thermal properties allow for walls that easily dissipate
heat, potentially eliminating the need for air conditioning units in hot countries. With
demand for fresh water around the world also on the rise, graphene may have the answer
to this challenge too. Physicists in China and the US have invented a graphene-based
desalination membrane that can remove salt from seawater. It’s a combination of a single
graphene sheet and a carbon nanotube mesh, which creates a centimeter-sized membrane.
Desalination can already be done with evaporation, but this uses a lot of energy. Reverse osmosis
is another method, but better membranes have been needed for years.
It could even kill bacteria and help save lives. Researchers at the Chalmers University
of Technology in Sweden have shown how attaching ‘vertical graphene flakes’ to the surface
of medical implants protects them from bacterial infections. This could eliminate the need
for antibiotics and lowers the chance of implant rejection, which is actually surprisingly
common. In fact, healthcare is now one of the leading sectors for graphene applications.
Its ultra-thin thickness is ideal for flexible circuits, a potential new way of monitoring
people for health purposes, or possibly harnessing energy from the wearer. They could be worn
on the skin in the form of ‘smart patches’, integrated into contact lenses or at the extreme
end used to create tiny sensors that travel in the bloodstream.
Although experts and the media have been saying this for more than a decade, it does feel
as though we are on the cusp of the long-awaited graphene era. Research has come a long way
in recent years, mass production now looks feasible, we’re seeing products launched
that demonstrate the material’s power and the list of realistic applications appears
to be growing by the day. The thing I think a lot of people lose sight of is that there’s
a pretty wide gap going from lab to mass produced product. It will take time for some of the
more ambitious proposals that we’ve covered here to see the light of day, if they ever
do, but there are still lots of reasons to be excited about the future of this incredible
material.
And the key to making advancements like this is having a strong understanding of scientific
principles and thinking. So if you’re like me and enjoy puzzling through how this all
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Thanks to Brilliant and to all of you for supporting the channel.
If you’re a member on my Patreon, I’ve got a little extra graphene video for you
there, so be sure to check that out. And if you liked this video be sure to check out
my video on the truth about solid state batteries. There’s been a lot of hype around that for
years too, but where do things stand today? Now, Jump into the comments and let me know
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if you think I’ve earned it. And as always, thanks so much for watching, I’ll see you
in the next one.