Fig. 3: Contact characteristics of solid-liquid interface and droplet dynamic behaviors on microstructures with different DS.
a Permeation effect facilitated by high dynamic pressure due to large transversal resistance and small solid-liquid contact area (SS-L) on the microstructure with small DS. Trace amounts of liquid pin on the microstructure after the droplet separating from the surface. b Complete droplet rebound without residue on the microstructure with medium DS. The vertical dynamic pressure can be released because the droplet is easy to spread horizontally and the SS-L is larger. The hierarchical superhydrophobic microstructure can suspend the liquid on the narrow flat although the flat is hydrophilic. c Solid-liquid interface adhesion on the hydrophilic large flat caused by large laser scan spacing. The surrounding superhydrophobic microstructure is not sufficient to support the liquid suspended on the wide hydrophilic flat, and the droplet is usually accompanied by residual liquid on the large flat when rebounding from the surface.
