Fabrication of Inherent Anticorrosion Superhydrophobic Surfaces on Metals

Abstract

The corrosion of metal materials is detrimental to petroleum pipelines, marine ships, heat exchangers, etc. To date, existing technologies have focused on improving corrosion resistances, such as anodization and painting. Superhydrophobic surfaces, which can retain air gaps between the corrosive liquids and solid structures, have shown effective corrosion prevention, but the inherent material property is not corrosion resistant. Herein, we reported a novel superhydrophobic surface with excellent corrosion resistance by using an electroplating method. The superhydrophobic surface consists of Zn–Ni and Zn–Co alloys, which are inherently corrosion resistant. We compared such a newly developed surface with superhydrophobic NiO/ZnO and ZnO coatings, respectively. The water contact angle of the novel superhydrophobic coating was larger than 150° after immersion into a NaCl solution for 48 h, while the other two coatings lost the superhydrophobicity. Furthermore, electrochemical measurement results demonstrated that our newly developed superhydrophobic coating exhibited the highest corrosion potential (−0.777 V) and lowest corrosion density (1.905 × 10–6 A cm–2). We envision that the inherently anticorrosion superhydrophobic coating can effectively prevent the corrosion of industrial metals.