Preparation of corrosion-resisting superhydrophobic surface on aluminium substrate

Abstract

ABSTRACTA superhydrophobic surface with micro-nano rough structure and corrosion-resisting property was prepared on aluminium substrate by a simple one-step wet chemical etching in HCl solution and in situ polymerisation method through thiol–ene coupling. The influence of etching time on wettability and morphology of the aluminium substrate surface was discussed. The surface morphology, chemical compositions and wettability of the aluminium substrate were investigated by scanning electron microscope, energy-dispersive X-ray spectroscopy and Fourier transform infrared. The water contact angle (WCA) and sliding angle (SA) were measured to study the superhydrophobicity. The results showed that a rough and irregular morphology was formed with 3.5 min etching, WCA and SA of the modified aluminium surface were 163° and 5°, respectively. The as-prepared surface revealed excellent corrosion resistance in 3.5% wt NaCl solution. The self-etching current density of the superhydrophobic aluminium surface was only 3.22 × 10−7 A cm−2.