We know that graphene is a single atom thick sheet of carbon with unique properties. It has a monolayer hexagonal crystalline structure and is 200 times stronger than steel. It is five times lighter than aluminum and has unique electrical or thermal properties. Since its discovery we have heard promises about how it will revolutionize many technologies, and in some cases it has. And how many of those promises remain to be fulfilled today?
Still pending ...
Graphene is great for touchscreens , OLEDs or LCDs, but no one has taken the step yet. Of course, everyone is clear that in the future we will have graphene electronic paper. Also ultralight mobile screens with this material, but ... not yet.
Its curious permeability to water, but impermeability to most other liquids and gases, makes it ideal for making filters. Soon many plans emerged to build desalination plants with graphene. It will be very important for many areas of the world to be able to get fresh water easily. But none of those filters have yet come out of a lab .
Experimental flexible OLED display
We know that carbon fiber is used a lot for the structure of airplanes, and the next step will be graphene . Very resistant, its electrical properties will improve resistance to lightning. And being in itself a sensor for the efforts, in addition to other advantages. An airplane has about 100 kilometers of wire and the graphene in the structure could save the most. But ... again it is still something in the pipeline.
Another promise of graphene is its effectiveness for photovoltaic cells. Almost transparent, a good conductor of heat and electricity, its behavior in this use is very promising. Not only cheaper and more efficient solar parks than the current ones are anticipated , but also less polluting to manufacture. In the future we could even wear garments whose exterior would charge our mobile thanks to graphene. But, like the other promises, it will be in the more or less distant future.
Resistant and conductive
Some of the actual and present uses of graphene are related to its mechanical strength. Just add it to other materials to multiply its strength . Metals or plastics benefit and these compounds are already used in aerospace technology, construction or mobile devices. There is already a first rubber compound for tires that contains graphene. Perpetuus Carbon (UK) manufactures graphene and has developed a rubber compound additive with the magic material that is already used in bicycle tires and will reach cars.
Bicycle tires with Graphene
On the other hand, graphene is the best conductor of heat in the world. As it is also strong and lightweight, it is ideal for use on parts that require conducting or dissipating heat. It is known that at least one large mobile phone manufacturer uses a graphene sheet to bring the heat from the chips to warmer areas inside the mobile.
One quickly seen use for graphene was to make capacitors. A capacitor is an electronic component that accumulates electrical charge. Unlike a battery, there is virtually no loss between charge and discharge. In addition, those uploads and downloads can be very fast. But until recently there were no huge capacitors: they are supercapacitors.
Chinese tram moved with graphene supercapacitors
Its greatest current application is in electric vehicles. But much bigger than a car or a motorcycle: buses, trams or trains. When one of these electrically powered vehicles brakes, its engines generate an enormous amount of power in a very short time. Only a supercapacitor can receive this energy and store it, as batteries need more time. And then deliver that energy back to get going. The Chinese manufacturer CRRC already has two models with graphene. One for buses, capable of moving it up to 10 kilometers after charging in just one minute. Another, for trams, charges in 30 seconds and moves the tram up to 6 kilometers . In its manufacture it is contaminated much less than with traditional materials, and they have no risk of explosion.
For cars or scooters
Zap & Go is a British company that also makes supercapacitors with carbon and graphene ions. Its objective is to replace many current lithium batteries: in scooters, drills, vacuum cleaners ... or cars. Started as a parallel company to the University of Oxford, they are very close to where the first lithium batteries were born 40 years ago. Now comes the turn of this new technology, cheaper to manufacture on a large scale, more ecological and safe, and more durable. A graphene "battery" (supercapacitor) can last 20-30 years in normal use.
Supercapacitors with graphene and carbon nanotubes
Another prominent manufacturer is the German Skeleton Technologies. They have patented a type of ultracapacitor that uses a graphene nanotube structure. They were among the first to jump into this technology , and they play with an advantage. They sell “batteries” of different sizes, and they have been used in competition (KERS in F1 or World Endurance), in some cars (start-stop system at traffic lights) or in the European Space Agency for different space systems. They have also specialized in large applications, for example to accumulate energy in wind power plants. When it is very windy, the excess energy is conserved so that in calm moments it can continue to be sent.
As we can see, little by little applications of the “magic” material graphene are arriving , although some of the most anticipated ones will still make us wait.