Effect of Substrate Surface Roughening on Anti - Corrosion Property of Graphene Oxide Coating

Abstract

Metal surface pre - treatment is an important step in the coating preparation process. In order to study the effects of carbon steel surface state on preparation of graphene oxide coating by electrophoretic deposition, the graphene oxide coatings were prepared on roughened and polished surfaces of carbon steel, respectively, and the lateral size of graphene oxide was measured by laser scattering instrument. The surface morphology of the roughened carbon steel was characterized by three - dimensional surface measuring instrument, optical microscope was used to perform micro analysis. The potentiodynamic polarization curve and electrochemical impedance spectrum of the coating were measured by electrochemical workstation. Results showed that the coating on the polished surface had obvious defects and looseness, the corrosion current density was 1.5 times that of the bare carbon steel, and the impedance value reduced, indicating that the corrosion resistance reduced. The rougher surface was conducive to the formation of a more uniform and dense coating, the corrosion current density was reduced by 10 times, the impedance value was increased. Surface roughening could improve the quality and corrosion resistance of graphene oxide coating.

Keywords

• graphene oxide coatings| electrophoretic deposition|surface roughening|electrochemical behavior