Rubbing off graphene

Vigorous mixing of a solution containing micro particles of graphite may produce graphene, a material with remarkable electrical, mechanical, optical and thermal properties. Researchers from TU Delft and Queen Mary University of London have now published an article based on a simulation of the process. They calculated the molecular dynamics which determine whether layers of graphene are released.

So how is graphene produced in liquid? The walls containing the solution move in opposite directions. This causes a strong shear flow in the solution. So strong in fact that it peels single-atom layers off the floating graphite particles. According to a review this ‘liquid exfoliation’ is regarded as ‘a cost-effective, efficient, and extraordinarily versatile method that has the potential for large-scale production of defect-free graphene’.

“Our model is the first to show in detail what happens at the micro and nano scales when graphene is produced from plain graphite using energetic fluid mixing,” says Dr Lorenzo Botto, researcher at the Department of Process & Energy at TU Delft. “The model will help the design of large-scale production processes, paving the way for graphene to be incorporated in commercial applications from energy storage devices to biomedicine.” Read the article in The Journal of Chemical Physics.

Graphene consists of a single atomic layer of carbon. A layer of graphene is about 100 times stronger than the strongest steel of the same thickness. It conducts heat and electricity extremely efficiently and is nearly transparent. (JW)