Formation of aluminum oxide nanostructures via anodization of Al3104 alloy and their wettability behavior for self-cleaning application.

• Control of wettability through changes of surface structure for self-cleaning. • Change of surface structure via anodization in K 2 HPO 4 /glycerol electrolyte. • Surfaces obtained from K 2 HPO 4 /glycerol electrolyte have higher wettability than those obtained from typical electrolytes. The Al 3104 alloy is widely used in the industrial field for building exteriors, heat blockers, and aluminum cans. These products are often exposed to long-term pollution, resulting in economic loss due to corrosion and the removal of pollutants. To solve these problems, self-cleaning of metal surfaces has been actively studied. Self-cleaning can be achieved by modifying hydrophilic or hydrophobic treatments to control the surface energy and surface structure. In the present study, the surface structure was changed through anodization technique. We fabricated three different structures of the top surface: nanotubes, porous, and nanopetals. The various nanostructures exhibited differences in wettability. Under the optimum conditions, the aluminum oxide layer exhibited hydrophilicity, which is a significant advantage for self-cleaning. [ABSTRACT FROM AUTHOR]