A simple and efficient method for preparing hydrophobic aluminum surfaces

Hydrophobic metal surfaces have broad application prospects in various fields due to their excellent properties like self-cleaning and anti-icing. However, the current methods to construct micro/nanostructures required for good hydrophobicity tend to be high-cost and may involve dangerous chemical reagents, which restrains further applications of these surfaces. In this paper, we propose a green and low-cost boiled water treatment method to fabricate micro/nanostructures on aluminum substrates, and the surfaces show good hydrophobicity after low surface energy modification. The preparation process for the micro/nanostructures is free of any chemical reagent, and the whole process can be completed within 1.5 h. Fabrication mechanism of this method is investigated by observing surface micro/nanostructures using a scanning electron microscope (SEM) and analyzing chemical compositions via an energy-dispersive X-ray spectroscope (EDS). The method may also be applied to construct the micro/nanostructures on other metal materials, and is expected to facilitate large-scale preparation and application of hydrophobic engineering metal surfaces.