Superhydrophobic surfaces for anti-corrosion of aluminum

Water-repellent superhydrophobic surfaces have been applied to metallic materials for anti-corrosion purpose. Here we discuss the origin of anti-corrosion property caused by the de-wetting on the surface of metals considering the fundamentals of electrochemical corrosion. In addition, we review the recent work on the fabrication of superhydrophobic surfaces on aluminum and its alloys with a focus on the anti-corrosion property. Textured porous structures made of low surface energy materials or coated with low surface energy materials not only reduce the contact with corrosive media but also inhibit the transport of corrosion reactants toward the metal substrate by trapping air within the porous structure. Various technologies for realizing hydrophobic/superhydrophobic surfaces on aluminum and its alloys, including the texturing of surfaces and coating with the low surface energy materials, have been demonstrated to enhance the anti-corrosion as well as de-wetting properties.