Fabrication of robust ceramic based superhydrophobic coating on aluminum substrate via plasma electrolytic oxidation and chemical vapor deposition methods

Abstract

This paper presents a ceramic based superhydrophobic coating fabricated on aluminum via plasma electrolytic oxidation and chemical vapor deposition methods. The morphology, chemical composition and wettability were characterized by scanning electron microscopy, energy dispersive spectrometer, and water contact angle (WCA). Water repellency, mechanical durability, anti-corrosion resistance and self-cleaning properties were investigated respectively. The results indicate that the prepared superhydrophobic coating featured net-like structured silica nanoparticles and concave pits with porous ceramic. Based on these characters, the prepared coating with a WCA of 160.5° exhibits excellent water repelling and self-cleaning properties. In addition, compared with bare aluminum, the corrosion current density of the prepared superhydrophobic coating is smaller by 3 orders of magnitude with a high inhibition efficiency of 99.76%. Furthermore, thanks to the ceramic based wear-resistant coating and protective micro-architectures, the prepared superhydrophobic coating demonstrates a superb mechanical durability. Therefore, the prepared superhydrophobic coating on aluminum is expected to offer potential opportunities for industrial applications in marine corrosive environments.