Electrospun Janus fabrics with directional water transport property for efficient water collection

Collection of clean water from humid air has attracted immense attention in recent years. Janus fabrics (JFs) have been widely employed to harvest fog droplets. Herein, a double-layer hydrophilic/hydrophobic Janus fabric was prepared by depositing polystyrene (PS) layers of different thicknesses on hydrophilic cotton fabric via one-step electrospinning technology. The thickness of the PS layer and the distance from the fog outlet to the fabric surface affected the water collection rate (WCR). The water collection rate of the JFs initially increased and then decreased as the thickness of the PS layer was increased. Benefiting from the timely drainage and directional droplet delivery, the JFs showed a 147% enhancement in the WCR compared with hydrophilic cotton fabric. This work may provide insight into the design and fabrication of fog collection systems with high efficiency to alleviate the freshwater crisis.