Facile fabrication of superhydrophobic surface with micro/nanoscale binary structures on aluminum substrate

The present work reports a simple method to produce the aluminum superhydrophobic surface based on an interface reaction between an aluminum foil and zinc aqueous solution. The products were characterized by field-emission scanning electron microscopy, X-ray powder diffraction and X-ray photoelectron spectrum. The field-emission scanning electron microscopy images show that the coating surface is composed of micro/nanoscale binary structure, which is similar to the structure of lotus leaf. The wettability of the coating surface was also investigated. It was found that after treatment with stearic acid, the wettability of the aluminum foil changed from superhydrophilic to water-repellent superhydrophobic. The complex micro/nanoscale binary structures along with the low surface energy lead to the high surface superhydrophobicity.