Protective sol-gel coatings for zinc corrosion: Precursor type effect

Various mono- and bi-layered sol-gel films have been prepared and applied as protective coatings for zinc corrosion in 0.5 M HCl solution. Smooth and uniform morphology are characteristic for thiol groups containing coatings while, surface deterioration is observed for others. The bi-layer morphology is similar to that of the outer layer. Hybrid mono-layer has higher protection ability than its corresponding bi-layers, except for bi-layers having vinyl groups containing outer layer. The protection abilities of mono- and bi-films are discussed in terms of film structure and functionality.