Graphene could soon be applied to other materials using a supersonic spray. This can provide high quality coatings of the unique substance, for use in a variety of applications.
Graphene is a sheet of carbon atoms one atom thick, arranged in a multitude of hexagons. The material has remarkable electrical and thermal properties which could soon revolutionize electronics, replacing silicon for most purposes.
The process of supersonic application is surprisingly simple. Researchers from the University of Illinois at Chicago and Korean universities experimented with a commercially-available supersonic nozzle, called a Laval, normally used for jet engines and rockets.
When graphene is sprayed on the substrate, the odd shape pieces like pentagons, "snaps" into a hexagonal formation during application. Despite this unusual behavior, the final product is nearly flawless. Manufacturing these nearly-flawless layers will be necessary if graphene is ever to be used in commercial electronics.
"Imagine something like Silly Putty hitting a wall - it stretches out and spreads smoothly. That's what we believe happens with these graphene flakes. They hit with enormous kinetic energy, and stretch in all directions. We're tapping into graphene's plasticity - it's actually restructuring," Alexander Yarin, co-leader of the study, said.
Graphene could be used to strengthen plastics and fabrics, as well as being used for electronic applications. One of the challenges for graphene development so far has been inconsistencies in the material. This new study suggests the substance, applied at high velocities, could form itself into nearly perfect sheets.
"Normally, graphene is produced in small flakes, and even these small flakes have defects," Yarin told the press.
When current technologies attempt to create large sheets of graphene, these small defects increase, ruining many of the desirable qualities of the unique material.
Alexander Yarin was conducting research on how to apply layers of graphene, and consulted with Sam Yoon, who was using the nozzles to apply other substances on substrates.
This method of application is simple, and the equipment needed is available in the open market. This means the practice could be scaled up to commercial production quickly and easily, allowing graphene to be used for products.
Graphene is the strongest material in the world, along with being flexible. It is more conductive than copper, and could allow the development of super-fast computers. Some developers are predicting graphene-based computers will be able to download a terabyte - 1,000 gigabyte - a second of data. Batteries made from graphene could provide cell phones that charge in just five seconds.
Research into the use of supersonic applicators to deliver sheets of graphene was profiled in the journal Advanced Functional Materials.
