Topography-Directed Hot-Water Super-Repellent Surfaces.

Natural and artificial super-repellent surfaces are frequently textured with pillar-based discrete structures rather than hole-based continuous ones because the former exhibits lower adhesion from the reduced length of the three-phase contact line. Counterintuitively, here, the unusual topographic effects are discovered on hot-water super-repellency where the continuous microcavity surface outperforms the discrete microneedle/micropillar surface. This anomaly arises from the different dependencies of liquid-repellency stability on the surface structure and water temperature in the two topographies.