Biomimetic Fog Harvesting with Synergistic Effects of Multiple Driving Forces

Water scarcity is a pressing global issue, prompting researchers to explore innovative solutions, such as harvesting water from the air. Drawing inspiration from natural materials like spider silk and cactus spines, this work has focused on developing structures with mixed wettability gradients to harvest fog from the environment. The hybrid wetting design, combining hydrophilic and hydrophobic properties along with a 3D structure, enhances the capture of water droplets by increasing the contact area with fog flow. This novel approach shows great potential in improving water capture efficiency. Besides, the wettability gradient facilitates the transport and rapid removal of water droplets due to the combined effects of gravity, the wettability driving force, and the Laplacian pressure. By emulating nature's water harvesting mechanisms, a generalizable technology is developed in this work that promises to significantly improve water collection from the air, particularly in arid and semiarid regions.