Review of the role of CVD growth parameters on graphene coating characteristics and the resulting corrosion resistance

Graphene coating on metals synthesized by chemical vapour deposition (CVD) is emerging as a disruptive approach to effective barrier coating against corrosion. CVD has been used to develop graphene coating on several transition metals and alloys. However, the reported degree of corrosion resistance due to graphene coatings varies in different studies. In fact, in some studies, corrosion resistance of the graphene coated metal has been reported to be even worse than the bare metals, which was attributed to the presence of defects in the CVD graphene coating and its highly cathodic nature. Some of the CVD parameters employed during graphene synthesis have been shown to profoundly influence the defect development in the graphene film, and their role in corrosion resistance. However, it may be prudent to review the topic. This review discusses: i) CVD graphene growth mechanism on different transition metals and establishes the importance of fundamental understanding of the influence of CVD parameters on nature and contents of defects, ii) corrosion resistance due to the graphene coatings developed using different CVD parameters, and (iii) scope of future research in optimizing CVD parameters for minimizing defect contents and maximizing corrosion resistance.