Smart Corrosion Inhibition of Mild Steel Using Mesoporous Silica Nanocontainers Loaded with Molybdate

In this research, mesoporous silica was served as the host of molybdate (corrosion inhibitor). The loaded mesoporous silica was dispersed in a paint matrix. The composite was then coated on the carbon steel surface. Polarization and electrochemical impedance spectroscopy (EIS) tests showed that the corrosion resistance of the scratched paint containing molybdate loaded mesoporous silica was better than the one without it or neat paint at near neutral pH. Charge transfer resistance regarding inhibitor loaded mesoporous silica showed a higher value in comparison with unloaded one. This parameter for the coating with inhibitor loaded mesoporous silica at the higher pH recorded 589300 Ω.cm2, while it was 209100 Ω.cm2 for un-loaded mesoporous silica. On the other hand, scanning electron microscopy (SEM) studies showed the release of corrosion inhibitor in the scratch zone which was due to the pH-sensitive release of corrosion inhibitor in the corrosive media.