Journal of Materials Science, Vol.52, No.2, 1089-1105, 2017
Surface-mechanical and electrical properties of pulse electrodeposited Cu-graphene oxide composite coating for electrical contacts
The current communication deals with elaboration of electrodeposited graphene oxide (GO)-reinforced copper composite coating with tribomechanical and electrical properties. Graphene oxide, chemically reduced graphene oxide (RGO) and thermally reduced graphene oxide (TRGO) with different concentrations (0.1, 0.5 and 1 g/L) were incorporated in the copper matrix. The surface-mechanical and electrical properties of the developed coatings were investigated for possible electrical contacts applications. The deposition process was carried out at a pH value of 1 +/- 0.02, which was sufficiently below the isoelectric point of RGO and TRGO to avoid possible agglomeration during deposition. A structural change of the synthesized specimens and the presence of GO in the composite coating were demonstrated from Raman spectra characterization. X-ray photo electron spectroscopy of some specific specimens (RGO, TRGO and Cu-0.5 g/L TRGO) was carried out to study the elemental composition, chemical state and electronic state of the elements present. Improvement of mechanical and electrical properties was clearly evident due to dispersion hardening caused by uniform dispersion of second-phase GOs. Cu-TRGO composite coating shows excellent electrical conductivity as compared to GO- and RGO-reinforced composite coatings due to removal of oxygen-containing groups after thermal reduction process.