Facile fabrication of multiple biomimetic patterned superwetting zinc surfaces with enhanced collecting efficiency from water mist

Abstract

Water shortage has emerged as a significant worldwide issue as a result of the frequency of extreme weather events like storms, droughts and climate warming. One possible way to address the world's freshwater deficit is to effectively extract freshwater from water mist. In this work, a series of biomimetic superhydrophobic-hydrophilic patterned zinc materials for mist collection was designed via mold pressing, anodic oxidation and laser-scanning methods. The fog collector is able to capture droplets efficiently and transport water quickly due to its unique array structure. The patterned superhydrophobic-hydrophilic zinc surface contained the highest water mist collection efficiency of about 10.89 g·m−2·s−1, which is 75 % higher than the original zinc sheet. The surface structure, chemical composition of the superwetting zinc materials were investigated by FT-IR, XPS, FESEM and EDS, respectively. In addition, the mechanical robustness, weather ability and enhancing mechanism of the prepared superwetting zinc surfaces were investigated via UV exposure, multiple thermal/cold cycles and sandpaper abrasion treatment. The good collecting efficiency from water mist of the obtained functional surfaces may provide ideas for the future design of mist collection materials.