A simple strategy towards construction of fluorine-free superhydrophobic aluminum alloy surfaces: self-cleaning, anti-corrosion and anti-frost

This work introduced a simple method to fabricate a superhydrophobic aluminum alloy surface based on a combination strategy of chemical etching using HCl/H2O2 mixture and modification by polydimethylsiloxane (PDMS). The chemical composition, morphology and hydrophobicity of the surface were characterized by FTIR, EDS, 3D optical profiler, SEM and contact angle system. The results show that the fabricated micro/nano-scale hierarchical structures after being modified with PDMS can results in a good anti-adhesion and resistance to wettability with a water contact angle as high as 161° and a sliding angle of 7°. Also, the superhydrophobic surface displayed excellent thermal stability and self-cleaning performance. Furthermore, electrochemical tests indicated that the superhydrophobic surface was endowed with good corrosion resistance property. The prepared surface was demonstrated to have a commendable resistance to corrosion, exhibiting a lower corrosion current density of 2.5 × 10–9 A/cm2 and a higher corrosion potential of − 0.58 V. Compared to original aluminum alloy plate, the superhydrophobic surface had an ability to delay icing with the obviously decreased frosting area. To a certain extent, these investigations opened up possibilities for applications of superhydrophobic surface, especially in the fields of self-cleaning, anti-corrosion and anti-frost.