Corrosion protection of Q235 steel in Pseudomonas aeruginosa- laden seawater environment using high barrier PDMS nanocomposite coating

Perfluorodecyltrichlorosilane (PFDS)-modified PDMS-ZnO hydrophobic coating and 2-ethylhexanoic acid (EHA)/PFDS-modified amphiphilic coating were fabricated. The effect of EHA on the barrier properties and corrosion protection effectiveness of PFDS-modified hydrophobic PDMS-ZnO coating was investigated using electrochemical impedance spectroscopy (EIS) and molecular dynamics simulation techniques. The EIS results showed the amphiphilic coating exhibited higher barrier and corrosion protection properties than the hydrophobic coating. The observed EIS results were confirmed by results of the water contact angle measurement, SEM, AFM, EDS and FTIR. The molecular dynamics (MD) simulation results revealed the nature of interaction between the amphiphilic coating and the corrodent, as well as the interaction between hydrophobic coating and the corrodent. The results clearly indicate that amphiphilic coating was most favourable for hydrophilic interaction, whereas the hydrophobic coating was well-disposed to hydrophobic interaction. These agree with the experimental results.