Self-cleaning graphene oxide based superhydrophobic coating on steel for improving corrosion and biofouling resistance

Due to its good mechanical properties, carbon steel is one of the commonly used structural materials. Nevertheless, carbon steel is susceptible to deterioration in the marine environment by the combined interaction of corrosive ions and microorganisms. Therefore, in the present study, a superhydrophobic (SHP) graphene oxide (GO) based coating on carbon steel is developed and this coating is intended to protect the substrate from the aggressive corrosive environment. A composite coating of GO flakes, zirconia nanoparticles (ZrO2) and silane solution was coated on carbon steel substrates using dip coating and obtained a maximum water contact angle (WCA) of 169 ± 1°. Morphology and composition of SHP composite coating obtained from microscopy and spectroscopy studies were correlated to their non-wetting property. The corrosion protection performance of GO-ZrO2-silane coated SHP carbon steel was found to be better than the uncoated carbon steel in chloride solution. Bacterial adhesion studies in two different bacterial cultures showed that the total viable count of bacterial cells on GO-ZrO2-silane coated SHP carbon steel samples was 4 to 5 orders less than that of the uncoated carbon steel samples. This study paves the way for new approaches to address corrosion and biofouling of carbon steel in aqueous conditions. Schematic describing the dip coating of GO + ZrO2 + silane on polished and phosphated carbon steel specimen followed by curing resulting in a water contact angle of ~169° Schematic describing the dip coating of GO + ZrO2 + silane on polished and phosphated carbon steel specimen followed by curing resulting in a water contact angle of ~169° Carbon steel specimens dip-coated with graphene oxide, zirconia nanoparticles and silane. GO-ZrO2-Silane composite coating was superhydrophobic with a water contact angle (WCA) of 169 ± 1°. Bacterial adhesion on SHP carbon steel sample was 4 to 5 orders less than the uncoated sample. SHP carbon steel exhibited good corrosion protection performance in chloride solution. SHP carbon steel showed excellent self-cleaning property and stability in wide pH range solutions. Carbon steel specimens dip-coated with graphene oxide, zirconia nanoparticles and silane. GO-ZrO2-Silane composite coating was superhydrophobic with a water contact angle (WCA) of 169 ± 1°. Bacterial adhesion on SHP carbon steel sample was 4 to 5 orders less than the uncoated sample. SHP carbon steel exhibited good corrosion protection performance in chloride solution. SHP carbon steel showed excellent self-cleaning property and stability in wide pH range solutions.