Integration of hydrophilic nanofibers into hydrophobic electrospun yarns for enhanced fog water harvesting in harp systems

Fog water harvesting provides a sustainable water source in regions with scarce freshwater. This study developed electrospun yarns combining hydrophobic thermoplastic polyurethane (TPU) and hydrophilic polyamide 6 (PA6) fibers for use in a harp-type fog collection system. The TPU–PA6 yarns achieved a water collection rate of 1.10 g cm −2 h −1 , exceeding hydrophobic TPU yarns by 56%. This improvement is attributed to the combined effects of the modified surface wettability and morphology, including the increased hydrophilic contribution and surface area, which together influence fog droplet capture, transport, and removal. Lower contact angle hysteresis (9.80 ± 1.76° for TPU–PA6 in compare to 19.73 ± 2.05° for TPU) also enabled faster droplet transport and removal. Overall, TPU–PA6 yarns show strong potential as efficient materials for enhanced fog water harvesting applications.