One of the biggest issues with graphene is how to get a good even surface with no flaws. In the current methods of production the flakes of the one atom thick carbon sheets can have flaws in them and, coupled with the difficulty of actually depositeing the flakes onto a substrate, it would be useful to find a method of application that could address these issues.
It seems that Korean scientists have developed a kinetic spray deposition system using a nozzle design that accelerates the particles to supersonic speeds which allows the expanding liquid on ejection to be converted into a directed kinetic energy. The carrier liquid evapourates leaving an even and well distributed coating behind.
By spraying graphene flakes in a carrier liquid onto substrates it is possible to get that flaw-free surface of single molecule carbon sheets, but also remover the flaws found in some of the original flakes. The thoght here is that the flawed graphene is stretched out in all directions as it is forced out of the nozzle, so allowing it to return to its default hexagonal pattern.
This must surely be a step in the direction of improving the process and cost of production as well as the final application onto surfaces.