High-flux and anti-salt solar desalination via scalable photothermal textiles with vertically confined water layers
Qian Zhang, Manyu Wang, Hao Yu, Ning Xu, Xingfang Xiao, Luqi Pan, Jia Zhu, Weilin Xu
Abstract
Interfacial solar evaporation plays a crucial role in desalination because of its sustainable, eco-friendly characteristics. However, major challenges to simultaneously achieving salt rejection, fast evaporation, and heat localization in solar desalination devices still remain. We propose a photothermal textile with vertically confined water layers for scalable, high-flux, long-term-reliable solar desalination. The photothermal textile consists of outer layers (carbon fibers) for solar absorption and core layers (hollow yarns) for water-feeding channels. Three-dimensional evaporators possess large evaporation areas and, thus, high evaporation rates, and the vertically confined water layers in the hollow yarns enable natural convection for effective salt rejection with negligible heat loss. Consequently, this photothermal textile achieves an evaporation rate of 2.05 kg m −2 h −1 in high-salinity brine (15 wt % NaCl solution) under 1-sun irradiation, with long-term reliability of over 20 days in continuous outdoor operation.