Improved corrosion protective performance of hybrid silane coatings reinforced with nano ZnO on 316 L stainless steel

In this research, silane hybrid coatings based on γ-glycidoxypropyltrimethoxysilane/ methyltrimethoxysilane/ 3-aminopropyl trimethoxysilane (GPTMS/MTMS/ APS) were produce by sol-gel method. ZnO nanoparticles were embedded in the silane coating and this exclusive silane coating was employed to 316 L stainless steel (SS) substrates by the dip-coating method. The surface characteristics of the samples were examined by FTIR analysis, XRD , SEM-EDS, and contact angle measurements. Further, the corrosion protection behavior of the coatings was examined in 3.5 wt% aqueous NaCl solution using potentiodynamic polarization , EIS, and SECM analysis. AFM was applied to determine the surface morphologies of the samples after the polarization test. Our results exhibited that the coatings enhanced the anti-corrosion performance of SS substrates. It was also obtained that the combination of GPTMS/MTMS/APS provided better corrosion protection properties and acts as a strong physical barrier to the corrosive molecules. The presence of nano ZnO further improved the protective barrier of the coating.