Laser Direct Writing of Tree-Shaped Hierarchical Cones on a Superhydrophobic Film for High-Efficiency Water Collection

• Published in: ACS applied materials & interfaces Vol. 9; no. 34; pp. 29248 - 29254
• Main Authors: Wang, Meng, Liu, Qian, Zhang, Haoran, Wang, Chuang, Wang, Lei, Xiang, Bingxi, Fan, Yongtao, Guo, Chuan Fei, Ruan, Shuangchen
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 30.08.2017
• Subjects: air; Araneae; droplets; films (materials); geometry; harvesting; hydrophobicity; Nepenthes alata; silk; transportation; wettability; hierarchical patterns; microfluidics; water collection; superhydrophobic; laser direct writing
• ISSN: 1944-8244; 1944-8252; 1944-8252
• DOI: 10.1021/acsami.7b08116

Directional water collection has stimulated a great deal of interest because of its potential applications in the field of microfluidics, liquid transportation, fog harvesting, and so forth. There have been some bio or bioinspired structures for directional water collection, from one-dimensional spider silk to two-dimensional star-like patterns to three-dimensional Nepenthes alata. Here we present a simple way for the accurate design and highly controllable driving of tiny droplets: by laser direct writing of hierarchical patterns with modified wettability and desired geometry on a superhydrophobic film, the patterned film can precisely and directionally drive tiny water droplets and dramatically improve the efficiency of water collection with a factor of ∼36 compared with the original superhydrophobic film. Such a patterned film might be an ideal platform for water collection from humid air and for planar microfluidics without tunnels.