Nano to micro structural hierarchy is crucial for stable superhydrophobic and water-repellent surfaces.

摘要: Water-repellent biological systems such as lotus leaves and water strider's legs exhibit two-level hierarchical surface structures with the smallest characteristic size on order of a few hundreds nanometers. Here we show that nano to micro structural hierarchy is crucial for superhydrophobic water-repellent surface. The first level structure at scale hundred nanometers allows sustain highest pressure found in natural environment plants insects maintain stable Cassie state. second leads dramatic reduction contact area, hence minimizing adhesion between solid two further stabilizes state by enlarging energy difference Wenzel states. stability nanostructural also higher restore superhydrophobicity easily after impact rainfall.