Construction of a superhydrophobic surface with long-term durability on 5052 Aluminium for corrosion protection

Superhydrophobic surfaces have been demonstrated to offer exceptional corrosion protection for metal surfaces. However, long-term stability issues have plagued superhydrophobic surfaces. In this study, a durable superhydrophobic surface on aluminum (SHC-Al) was created using etching combined with anodizing followed by polydimethylsiloxane (PDMS) modification. To optimize the multi-scale rough structures, the optimal anodizing conditions were explored in detail. The superhydrophobic surfaces were analyzed using Field emission scanning electron microscopy (FESEM), Confocal laser microscopy (CLSM), X-ray energy spectrometry (EDS), Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), contact angle (CA) measurements, stability tests, and electrochemical analysis. The results reveal the successful preparation of a nest-like micro-nano composite structure on metal surface, and the contact and sliding angles of SHC-Al were measured at 157.6° and 6°, demonstrating the formation of excellent superhydrophobic surface. Electrochemical tests showed a corrosion current density of only 1.38 × 10^–9 A∙cm^-2 for SHC-Al, with a corrosion inhibition efficiency of 99.97 %, highlighting its outstanding anti-corrosion performance. Furthermore, stability tests demonstrated the SHC-Al surface had long-term durability. This study not only provides new evidence for the preparation of long-lasting superhydrophobic surfaces, but also provides a new solution for the practical application of superhydrophobic surfaces.