Fabrication of Superhydrophobic Aluminum Surfaces Using Modified Nanoparticles and Ionizable Surfactants

In this study, plates of aluminum are made superhydrophobic via wet etching followed by deposition of nanostructure and microstructure. Etched surfaces are coated with modified nanoalumina using an ionizable surfactant. Key parameters governing the hydrophobicity such as type of the etching solvent, type of the surfactant, etching time, nanoparticle size distribution, surfactant concentration and annealing temperature are investigated. Infrared spectroscopy (IR), dynamic light scattering (DLS), scanning electron microscopy (SEM) and water contact angle (WCA) measurements are used to characterize the treated surfaces. A WCA greater than 150 degrees is obtained and in order to estimate the efficiency and mechanical durability of the coatings the samples are tested in emulated sea-water. Water jet tests prove the mechanical stability of the samples. Our fabrication method results in good hydrophobicity and self-cleaning behavior of the Al surface and the obtained results may be useful for industrial applications.