Facile fabrication of superhydrophobic nanostructures on aluminum foils with controlled-condensation and delayed-icing effects

Superhydrophobic alumina films with a 2D close-packed array of nanospheres have been successfully fabricated on industrial aluminum foils by a simple anodization method and following modification. The water contact angle of the resultant surfaces is about 154.6° ± 1.4° and the adhesion of water droplets is very weak. Moreover, spherical droplets grow sparsely on the as-prepared superhydrophobic foils during cooling and can be liquid without ice formation for more than 30 min after being continuously cooled to 0 °C. Such foils have significant application prospects in high-efficient heat exchangers and products operating under low temperature.