Macrotribological behavior of the graphene surface structured in a cylinder array

We proposed a technique of processing the graphene surface, characterized by the sputtering of a cylinder-array structure to improve its macrotribological properties and prolong wear-proof lifetimes. Graphene was grown on Cu foils by chemical vapor deposition and transferred to the SiO2/Si substrate. A Pt cylinder array on graphene surface was prepared by magnetron sputtering technique. The microstructure and macrotribological behavior of graphene surface with and without a cylinder-array structure were comparatively investigated. The different macrotribological behaviors were analyzed by Raman spectra and X-ray photoelectron spectroscopy. The results indicated that the graphene without a cylinder array was easily rubbed off and extruded on both sides of the wear track during the friction test. On the other hand, the graphene with Pt cylinder array exhibited better macrotribological performance because Pt cylinders had certain pinning effects on graphene sheets and prevented graphene sheets from slipping. The Raman spectra of the wear track revealed that the graphene oxide layer and amorphous carbon formed on the wear track during friction test, which caused the reduction in the surface energy and sliding resistance of film with Pt cylinders.