Graphene-coated nanodiamonds result in very low friction

Ars Technica : Superlubricity is a phenomenon that occurs when the coefficient of friction between two surfaces is dramatically reduced to near 0. Until now, it had only been detected in small samples of pairs of incompatible crystalline surfaces. Now a team from Argonne National Laboratory has produced superlubricity on a larger scale. Initially working with graphene and diamond, they tested two surfaces, one covered in graphene and one covered in diamond. The coefficient of friction was low, but not to the point of superlubricity. They noticed, however, that the graphene splintered and created curls of material that then collapsed under the pressure. Adjusting the setup, they placed nanoscopic diamonds between the two surfaces, and the coefficient of friction dropped dramatically. Electron micrographs revealed that the curls of graphene wrapped themselves around the nanodiamonds, which acted like ball bearings.