A simple “two foil” approach to the fabrication of hierarchical superhydrophobic surfaces

Hierarchical superhydrophobic surfaces were prepared using a simple “two foil” method, which employed an interfacial reaction between an aluminum foil and a copper foil in the ammonia solution. The results from the scanning electron microscopy observations indicated that the biomimic surfaces composed of bayerite nanorods and hierarchical structures, and the X-ray diffraction patterns confirmed that the formed nanorods were the crystallized bayerites. Such bayerite surfaces can be further modified with stearic acid, leading to the superhydrophobicity with a contact angle of 165.14° and very low sliding angle.