Recent advances in preparation of metallic superhydrophobic surface by chemical etching and its applications

In the past few decades, inspired by the superhydrophobic surfaces (SHPS) of animals and plants such as lotus leaves, rose petals, legs of water striders, and wings of butterflies, preparing metal materials with metallic SHPS (MSHPS) have attracted great research interest, due to the great prospect in practical applications. To obtain SHPS on conventional metal materials, it is necessary to construct rough surface, followed by modification with low surface energy substances. In this paper, the action mechanism and the current research status of MSHPS were reviewed through the following aspects. Firstly, the model of wetting theory was presented, and then the progress in MSHPS preparation through chemical etching method was discussed. Secondly, the applications of MSHPS in self-cleaning, anti-icing, corrosion resistance, drag reduction, oil–water separation, and other aspects were introduced. Finally, the challenges encountered in the present application of MSHPS were summarized, and the future research interests were discussed.