Enhancement of corrosion resistance by electrophoresed graphene obtained through ionic solution based electrochemical exfoliation

Abstract

The present work describes the electrochemical synthesis of few layer graphene nanosheets (FLGNs) through a green, non-toxic route in an ionic solution having four different stoichiometric solutions. The FLGNs have been characterized by X-ray diffraction, UV, RAMAN and FTIR to understand the chemical structure. UV, FTIR and EDS exhibited the presence of functional groups. The average particle size of FLGNs measured through DLS was in the range of 300–450 nm with good stability behaviour as seen through zeta potential measurements. SEM, TEM and AFM depict a layered morphology of the FLGNs. The synthesized graphene was electrophoretically deposited onto copper with different iterations i.e. time and number of layers and corrosion tests as well as EIS analysis of the coated copper was conducted in 0.6 M NaCl solution. SEM micrographs show layer-upon-layer deposition of graphene on copper substrate. Polarization tests and impedance measurements highlighted the efficiency of graphene as a barrier against corrosion in comparison to uncoated substrate. Authors also made an attempt to understand the effect of different layers of the coating on the substrate and its protection ability. It was found that 2 layered coatings offered better resistance in comparison to others. On an overall note, it can be stated that the choice of graphene for corrosion prevention is justified with the need for further exploration.