Determination of optimum concentration of cloisite in an eco-friendly silane sol-gel film to improve corrosion resistance of mild steel

In this study, the effect of cloisite concentration on the protective performance of an eco-friendly silane sol-gel coating consisting of tetraethoxysilane (TEOS), methyltriethoxysilane (MTES) and glycidyloxypropyltrimethoxysilane (GPS) applied on mild steel substrate was investigated using electrochemical techniques and surface analysis. Through taking advantage of electrochemical impedance spectroscopy, potentiodynamic polarization and electrochemical noise measurements, the optimum concentration of nanoparticles was determined. In the presence of the cloisite content, superiority of the hybrid silane film was connected to the enhanced barrier properties, confirmed by FE-SEM, FTIR and water contact angle studies. Moreover, a good trend correlation was observed between the noise resistance and low-frequency impedance modulus data.