An investigation on titania multilayer coatings for enhanced corrosion resistance of carbon steel in simulated seawater by sol–gel dip coating

Abstract

A TiO2 multilayer was investigated to be a low cost and high protection efficiency for carbon steel in simulated seawater. This study applied group theory for crystalline materials in a combination with DFT + U simulation to predict Raman spectra of TiO2 – anatase and rutile phases. The simulated spectra were used as a peak-search-match reference for experimental Raman spectra. It also indicated that the coatings produced out of polycrystalline structures including anatase and rutile phases with large grain sizes and boundaries. Furthermore, the electrochemical measurements including potentiodynamic polarization and electrochemical impedance spectroscopy for the 1–8 TiO2 layers were performed to reveal the anticorrosion properties of the coatings and the optimal values were pointed out. Based on those results, the protection mechanism of the TiO2 multilayer coating was also suggested in the manuscript. Keywords: Carbon steel, Titania multilayer coating, Sol–gel dip coating, Corrosion protection, Electrochemical measurement