Multibioinspired JANUS Membranes with Spatial Surface Refreshment for Enhanced Fog Collection

Abstract The increasing scarcity of freshwater motivates economical and practical approaches, especially bioinspired ones, to collect water from the atmospheric environment. The enhanced water collection can be achieved by the synergistic action of an effective surface refreshment of fog droplets and a rapid transport of harvested water. Here, a multibioinspired Janus membrane is presented with combined hybrid wettability of Namib desert beetles, curvature gradient of shorebird's beaks and capillary wicking of tree roots, which enables not only a frequent horizontal surface refreshment due to its hybrid wettability, but also an efficient vertical one underpinned by curvature gradient and capillary wicking. This unique spatial surface refreshment shows a 125% enhancement in fog collection compared to that on conventional Janus membranes. Meanwhile, the multibioinspired Janus membrane possesses a robust stability of the Janus state, which guarantees a high‐efficiency fog collection for a long time. It is envisioned that the design strategy for efficient and weatherable fog collection is promising for a wide range of applications.