9 amazing uses for graphene, from filtering seawater to smart paint
Graphene is a single layer of graphite — also known as that soft material commonly found in pencil lead — with the atoms arranged in a honeycomb-like, hexagonal pattern. While that description is decidedly unexciting, graphene is actually emerging as one of science’s most versatile new materials.
Just one atom thick (or thin, depending on how you think about it), graphene is among the strongest materials in the known universe, with 100 times the strength of steel, an astonishing amount of flexibility, and a whole lot of other talents lurking beneath the surface.
Do you remember that classic scene from The Simpsons in which Homer is offered “wax lips,” described by the salesman as “the candy of 1,000 uses?” Well, graphene is the wax lips of the material science world. And while we don’t have time to detail 1,000 uses, here are some of the most exciting graphene discoveries made so far.
Creating the world’s thinnest light bulb
Imagine a flexible, transparent display or light strip that’s just a single atom thick. That’s something graphene could help make a reality, as demonstrated by research from scientists at Columbia (University) Engineering, Seoul National University, and Korea Research Institute of Standards and Science.
By attaching small strips of graphene to metal electrodes and passing a current through them, the graphene was shown to heat — and light — up. Columbia professor James Hone described it as “the world’s thinnest light bulb.” Finding a way to translate this breakthrough into wearables such as smart clothing would be revolutionary.
Acting as a superconductor
Graphene can also act as a superconductor, meaning that electrical current is able to flow through it with zero resistance, a discovery that was made by researchers at the United Kingdom’s Cambridge University. The effect is activated by coupling the graphene with a material called praseodymium cerium copper oxide (PCCO).
Why do superconducting materials matter? Because in the future ,they could provide a source of unlimited energy, since they don’t constantly need to be resupplied with current.
“One day, the dream is to make your computer or your iPhone work without dissipating energy,” junior research fellow Angelo Di Bernardo, one of the researchers on the project, told Digital Trends. “You’ll just charge it once and then you can forget about having to charge it again its entire lifetime.”
A better speaker system
To produce sound, regular speakers create a pressure wave in the air by physically moving back and forth. Graphene could eventually offer a different approach. Researcher from the U.K.’s University of Exeter have demonstrated how graphene can create a non-moving solid-state audio device that may one day replace your existing bulky sound system with something called thermo-acoustic sound generation.
Instead of physically moving a component, this process works by using graphene to periodically vary the temperature of the air at a very high rate — enough to generate sound at audible frequencies and much higher, ultrasonic frequencies. The result could be the ability to incorporate speakers into ultrathin touchscreen technologies, in which the screen is able to produce sound on its own. No separate speakers required.
Body armor stronger than diamonds
Ella Maru Studio
A single layer of graphene is awesome. You know what’s even more awesome? Two layers of graphene combined. That’s what researchers from Georgia Tech recently showcased with a demonstration of how two-layer epitaxial graphene film — just two atomic layers of graphite — can withstand perforation by a diamond tip.
The hope is to develop this into ultrathin body armor, as light as foil, but strong as diamond, that is capable of stopping a bullet dead in its tracks. (Interestingly, the graphene shield’s ultra-hardening effect only results when two sheets of graphene are used, with extra layers appearing to have a detrimental effect.)
Filtering salt from seawater or color from whisky
Graphene membranes can be used to create a sieve finer than one you’ll find in any restaurant kitchen. One study demonstrated that a graphene membrane can filter 85 percent of salt out of seawater, which isn’t quite pure enough for drinking purposes, but is perfectly acceptable for agricultural use.
Think that’s impressive? It’s nothing compared to recent research coming out of the U.K.’s University of Manchester, where researchers used a graphene membrane to filter the color out of whisky — leaving it as a transparent liquid.
“The absence of dye molecule permeation was apparent even from the color of the solution after filtration,” Professor Rahul Nair from the U.K.’s University of Manchester told Digital Trends. “The original dye solution is colorful, while after filtering through the [graphene oxide] membrane, the solution lost its color and became a pure solvent.”
The paint of the future
Imagine if you could paint a building with a special coating that changes color when it senses that the underlying structure is in need of repairs. That’s what researchers at Germany’s Leibniz Institute of Polymer Research achieved with a smart graphene coating that indicates breaks and fractures by changing color.
Inspired by the way that fish scales reflect light, the coating is designed to amplify particular wavelengths of light, but dull others. The graphene flakes are placed onto a surface at certain angles so that, if compromised in some way, they’ll bounce back red, yellow, and green light, while noncompromised areas will not.
Cleverly, the color of light can change according to the severity of an area’s stress, so structures could conceivably be color-coded to show how major a particular area of damage is.
Tracking our health
It’s not just building health that graphene’s good at detecting. Researchers at the University of Illinois at Chicago have demonstrated that it can help detect cancer cells, too. In an experiment, they placed brain cells taken from mice onto a graphene sheet, and found that it was able to distinguish between a single cancerous cell (glioblastoma or GMB cell) and a normal cell.
Other researchers at the University of Texas at Austin have also created graphene-based temporary tattoos capable of tracking a person’s vital signs, such as their skin temperature and hydration.
Recharging our gadgets
Graphene can also be used to create new batteries that recharge super quickly. One Chinese company called Dongxu Optoelectronic has built a battery pack called the G-King, which has a giant 4,800mAh capacity, but can reportedly charge from empty to full in just a quarter of an hour.
The cell is also supposedly strong enough to be discharged and recharged 3,500 times — which is way more than a regular lithium-ion battery.
Creating some kickass running shoes
Starting this year, you’ll be able to buy running shoes made using graphene, thanks to a partnership between the U.K.’s University of Manchester and sportswear brand inov-8. The shoes have already been put through their paces in the lab, and the graphene composite rubber outsoles (the part of the shoe actually featuring graphene) are reportedly much stronger and more stretchy than traditional materials, making the shoes more resistant to wear and tear.
Hopefully the second-gen kicks will also filter saltwater, protect you from bullets, recharge your mobile devices, and cure cancer — for good measure!
- Like your whisky straight, no color? Graphene turns aged spirit transparent
- Graphene’s next trick? Creating foil-thin body armor that’s harder than diamonds
- Great balls of graphene: New Samsung tech could charge phones five times faster
- Graphene-based wearable could help save babies from ‘crib death’
- The world’s first graphene running shoes are coming in 2018