Advantage of super-hydrophobic surface as a barrier against atmospheric corrosion induced by salt deliquescence

This study demonstrates the advantage of using super-hydrophobic surface as a barrier against atmospheric corrosion induced by salt deliquescence. Different from the behavior on hydrophilic and hydrophobic surfaces, deliquesced NaCl particle slips off super-hydrophobic surface inclined at an angle of ∼20°, thereby preventing corrosion of underlying substrate by deliquesced salt. The observed slipping behavior could be attributed to lubrication action of saline solution between deliquesced NaCl particle and super-hydrophobic film, as well as weak attraction between saline solution and substrate. Electrochemical measurements prove that the existence of air film contributes to the enhancement of barrier performance of super-hydrophobic film.