Graphene coating on a nickel-copper alloy (Monel 400) for microbial corrosion resistance: Electrochemical and surface characterizations

• Graphene coating is deposited successfully on Monel alloy by CVD technique. • Graphene coating provided significant corrosion inhibition in biotic solution. • Bacteria colonies and dense biofilm is observed on uncoated Monel surface. • Little bacteria attached on graphene-coated Monel. Graphene is an attractive 2D coating material because its remarkable physico-chemical properties enable numerous applications. Graphene coating was deposited on Monel 400 alloy by chemical vapour deposition (CVD) for corrosion resistance in a marine environment containing sulphate reducing bacteria (SRB). Surface morphology and coating characterization were performed using scanning electron microscopy (SEM) and Raman spectroscopy. Electrochemical results revealed that the multilayer graphene coating that replaced the native protective oxide layer on the Monel 400 surface provided superior corrosion resistance in the abiotic and biotic solutions. Post corrosion characterisation, using SEM and FTIR, supported the electrochemical findings.