Growth of graphene film on Cu foils and graphene transfer process as a wear resistance surface coatings

Graphene has attracted a great interest because of its exotic mechanical, electrical and thermal properties. It also has lowest friction and low corrosion rate, these properties of graphene are explored very little, where researcher use Graphene Nano Platelets (GNP) made from Graphite. The oxidation and reduction process leaves the graphene with several epoxy groups on the surface which increases the friction coefficient and corrosion rate. In order to achieve the best values of the one needs to use high quality single or bilayer graphene. In this article we propose a low cost growth method for graphene and transfer process for making graphene coating on various surfaces. Here, we report the growth of single/bilayer layer graphene by chemical vapor deposition (CVD) using a rapid thermal processing (RTP) system with infrared heating. Prior to deposition of graphene, the Cu foils were annealed in a hydrogen reducing atmosphere at 1000 °C. Graphene films were grown on these annealed copper foil using 4 sccm 112 and 12 sccm CH₄ at 980°C for 5-30 minutes at 2.6x10^-2 mbar pressure. The grown films were characterized by Scanning Electron Microscope and Raman spectroscopy with mapping to investigate morphology of graphene. Structural characterizations suggest that graphene films are about 90% single/bilayer layer regions thorough out the Cu foils. Raman spectra of graphene sample grown for 30 minute has shown I2D/IG ratio of 3.83, indicating high quality graphene. These Cu samples are tested for wear rate with and without graphene and the results are presented in details. We demonstrate simple chemical process using which these graphene films can be easily transferred to any desired surfaces without damage. (author)