Fluorine-free preparation of self-healing and anti-fouling superhydrophobic Ni3S2 coating on 304 stainless steel

Abstract

Bioinspired designed superhydrophobic surfaces with various properties have aroused enormous concern. In this work, a superhydrophobic Ni3S2 coating was introduced onto 304 stainless steel via a fluorine-free and economical approach. The achieved superhydrophobic coating was significantly repellent to the infiltration of water. By means of the cooperation of Ni3S2 nanorods and low surface energy, a stable Cassie state was formed on this coating, ensuring bouncing water droplets could not be pinned. In addition, the superhydrophobic coating displayed superior stability even if it was subject to long-term ethanol immersion or heating treatment at 300 °C. Moreover, with the help of heating treatment, the coating still could regain superhydrophobicity after suffering from five cycles of O2 plasma etching. Furthermore, the anti-fouling test demonstrated contaminations could not pollute the steel surface due to an effective barrier formed by the superhydrophobic coating. This presented work is expected to provide promising inspirations for future applications in superhydrophobic materials.