Electrophoretic Deposition of Graphene on Copper and its Corrosion Behaviour

Abstract

Graphene is a single layer of pure carbon atom that are bonded together in hexagonal or honeycomb lattice structure. The gradual destruction of metal surface by chemical or electrochemical reaction with their environment forms corrosion. The graphene layer has been used as protective thin film on metal surface by electorphoretic depositon (EPD). In the present work, graphene has been synthesized by electrochemical intercalation and exfoliation of pyrolytic graphite sheet by various electrolytes (H2SO4, HNO3, and HCLO4) in varying concentration. The prepared dispersed graphene oxide (GO) solutions were deposited on copper surface with working area of 2cm2 by electrophoretic deposition technique at various (0.1, 0.5, 1 wt %) concentration of graphene. The sodium dodecyl sulfate (SDS) anionic surfactant has been used as binder to increase the thickness of coating. The graphene oxide coatings were used with the aim that it will act as a protective layer for corrosion of Cu substrate. The thickness of the graphene coated thin film was characterized by surface profiler and atomic force microscopy. Morphology of graphene nano sheets and coated graphene was analyzed by FESEM, which has showed clearly microstructure of GNS layer. Topography of graphene coated specimen characterized by AFM and crystal structure, crystalline planes and phases of graphene sheet were characterized by X-ray diffraction. (0 0 2) and (1 0 0) planes showed the graphene sheet has been confirmed by X-ray diffraction. The electrochemical corrosion behavior of graphene coating on Cu in 0.1M NaCl solution has been investigated by potentiodynamic linear sweep voltametry technique. However, the tendency (corrosion potential) is nobler for bare copper substrate. The study needs further experiment and optimization to reach to an affirmative conclusion. The application of GO layer has improved the corrosion resistance property of coated Cu due to better barrierquality of GO layer.