Fabrication of superhydrophobic PDMS/TiO2 composite coatings with corrosion resistance

In this study, a combination of hydrothermal and sol-gel methods was used to prepare superhydrophobic polydimethylsiloxane (PDMS)/TiO2 composite coating with good self-cleaning properties and corrosion resistance. The structural, surface roughness and wettability behavior of the PDMS/TiO2 superhydrophobic coatings were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and contact angles measurements. Results showed that surfaces of composite coatings possessed rough hierarchical micro/nanostructures, especially, the surface water contact angle is as high as 160° and the sliding angle is less than 2.1° when the ratio of PDMS/TiO2 was 1:5. In addition, through a series of high-temperature exposure, acid-alkali resistance, self-cleaning, and electrochemical corrosion tests, it was also found that the superhydrophobic surface with a PDMS/TiO2 ratio of 1:5 had excellent properties, and showed certain practicability in terms of anticorrosion, antipollution and durability. Therefore, it can be concluded that this kind of corrosion resistant superhydrophobic PDMS/TiO2 composite coating with simple operation, high performance and multi-scale use on metal substrates has good application prospects in harsh environments.