Simple fabrication of superhydrophobic/superoleophobic surfaces on copper substrate by two-step method

Multifunctional surfaces are in urgent demand in particular fields. In this work, we report a low-cost preparation of superhydrophobic/superoleophobic surfaces on copper substrate by rapid two-step process. The deposited Zn surface modified by stearic acid showed good superhydrophobicity with a water contact angle of 158.3° and a sliding angle of 4.6°. Interestingly, a remarkable Zn surface with reversible wetting transition between hydrophilicity and superhydrophobicity could be easily realized by the alternation of annealing and modifying. The wetting transition process was rapid and only took 13 min for each cycle, depending mainly on the change of the surface elements. Moreover, the modified-TiO2 suspension was coated onto the deposited Zn surface to construct a composite surface with micro/nano rough structures, which possessed excellent superamphiphobicity with contact angles of 161.8° and 152° toward water and oil respectively, and showing great mechanical strength and stability. The novel materials exhibit a promising perspective in many applications, such as wettability transition of surfaces, water proof and oil proof.