Electrodeposition of hierarchically structured superhydrophobic Ni-PTFE composite coating with remarkable corrosion resistance, chemical and mechanical stability

One of the main problems of superhydrophobic coatings is the low mechanical and chemical stability, which limits the industrial applications of these coatings. The purpose of this research is to create Ni-PTFE composite coatings with hierarchical morphology by electrodeposition method, in order to increase the corrosion resistance, and to improve the mechanical and chemical stability. Ni-PTFE Composite coatings were fabricated by adding different concentrations of PTFE particles (5, 10, 15, 20, 30, and 40 g/L) into the Ni electrodeposition bath. The effect of PTFE concentration on morphology, wettability, and corrosion resistance of the coatings was investigated. The results showed that when an optimum concentration of PTFE (15 g/L) is introduced in the electrodeposition bath, not only the hierarchical morphology of the Ni coating is preserved; but also the maximum contact angle of 158° and the minimum corrosion current density of 0.03 µA/cm2 was achieved. The long-term chemical and mechanical stability tests showed that by embedding of PTFE particles with hydrophobic nature, into the hierarcically structured superhydrophobic nickel coatings, higher mechanical and chemical stability is obtaind.