Design and fabrication of a stable Ni-PTFE-SiC superhydrophobic anticorrosive coating by electrodeposition

Abstract

Superhydrophobic coatings show great application potential in many fields, but they have not been widely used due to poor stability. A Ni-PTFE-SiC composite coating was proposed in this paper. Firstly, the Ni-PTFE-SiC coating structure was designed by molecular dynamics simulations. The feasibility of superhydrophobic effect of this structure and the adsorption stability of the composite coatings were proved. This approach can also be used to avoid trial and errors when selecting other similar candidate substances. Then, the Ni-PTFE-SiC superhydrophobic coatings were successfully prepared by composite electrodeposition, with the water contact angle of more than 155° and the sliding angle of close to 0°. The effects of current density, deposition time and nanoparticle concentration on the wettability and morphology of the coatings were also investigated. Through comparative experiments, the best preparation parameters were: PTFE 14 g L−1, SiC 6 g L−1, primary current density 7 A dm−² (10 min) and secondary current density 15 A dm−² (5 min). This preparation method doesn’t need additional modification with low surface energy substances like the traditional preparation process, and greatly improves the corrosion resistance, wear resistance and durability of the coatings.