Industrial production of asymmetric wettability patterned fabric for efficient atmospheric water harvesting

Abstract

While harvesting water from the atmosphere is considered as a promising technology to address the increasing issue of water scarcity, its wide applications are still limited by the difficulty in mass production of water harvesting materials. Here, an industrial-producible asymmetric wettability patterned fabric (AWPF) with high water harvesting capacity is developed using a continuous and low-cost weaving technology. Four textile patterns are developed for high-efficiency atmospheric water harvesting. The alternating patterned surface in AWPF is constructed with hydrophilic bumps and hydrophobic grooves using one set of green fluorine-free superhydrophobic polyester warp yarns and two sets of superhydrophobic polyester/hydrophilic viscose weft yarns. We optimized the water collection performance of the single-sided AWPF by spraying co-MBAA-DVB superhydrophobic material on the back of the AWPF to construct a wetting gradient, that is, double-sided AWPF. The double-sided AWPF shows a strong water harvesting capacity of 2840.2 mg·6h−1·cm−2, which increased the water harvesting efficiency by 43.2 % compared with the unoptimized single-sided AWPF. To reduce the pressure drop, 6 mm wide the double-sided AWPF was designed, resulting in a water harvesting capacity that is 1.23 times higher than that of without cutting. This advanced industrialized weaving technology with an asymmetric fabric structure design holds great potential for substantial water harvesting.