Bioinspired Integrative Surface with Hierarchical Texture and Wettable Gradient-Driven Water Collection

At present, collecting water directly from the atmosphere has become an effective means to solve the growing shortage of fresh water. Inspired by the structures of trichomes (hairs) of Sarracenia to capture fog and transport water, a series of different high-low rib-like hierarchical texture surfaces were prepared based on the laser method. These surfaces have gradient superwetting and adhesion because of the differences in subsequent preparation methods. In addition, this work discusses the effect of the above performance differences on the efficiency of fog collection and the surface condensation characteristics during fog collection. The results show that the surface of the laser-prepared sample with the mixing unit combination has more efficient fog collection efficiency and droplet removal rate. After 30 min, the amount of drip measured in the atmospheric environment is 8.4 times that of the polished surface. This indicates that the multihierarchical textured surface and superhydrophobicity are essential for improving the droplet removal rate and coagulation efficiency.