Application of the restricting flow of solid edges in fabricating superhydrophobic surfaces

In this article, a simple method of pressing a conical frustum into liquid was adopted to explore the ability to restrict flow around their edges. On the basis of experiments and theoretical analyses, the restricting force Deltaf and the pressing work DeltaE(w) were used to characterize the ability to restrict flow around the edge for water or formamide, which were found to be closely related to the geometric morphologies of edges and the liquid and material characteristics. The ability to restrict flow around the edge may be enhanced by increasing the rise angle omega and the size of edge circles and using a high-surface-energy liquid. Inspired by this, the superhydrophobicity of the materials with lower hydrophobicity has been successfully obtained by constructing close microedges on their flat surfaces. We believe that these findings would help to widen several novel applications to high-adhesion superhydrophobic surfaces.