Hydrogel fiber fabric combining rapid water transport, thermal localization, and large-scale production for ultra-high salt-resistant solar desalination

Solar vapor generation (SVG) is one of the most promising strategies for addressing freshwater shortage crisis. However, fewer existing solar evaporators combine excellent evaporation rates, salt-resistant, and large-scale production potential, which are the keys to realizing industrialization. Herein, sodium alginate/reduced graphene oxide (SA/rGO) hydrogel fibers are prepared via complex nano-network structures and proposed a compact hydrogel fiber fabric (HFF-C) evaporator by combining the advantages of hydrogel and fabric for the first time. The HFF-C evaporator has a synergistic impact based on its porous structure and capillary effect between the fibers as well as good thermal management, which achieve both efficient water transport and thermal localization. The HFF-C evaporator constructed exhibits an excellent evaporation rate (4.13 kg m−2 h−1) in 20 wt% brine under one sun illumination, and salt is not deposited on the surface of the evaporator over 8 h of operation, which is the highest reported value to our knowledge. Moreover, an HFF-C evaporator with a large size of 13*100 cm2 is successfully prepared by a multi beam loom. This study proposes a new design idea for a solar hydrogel-based evaporator with an excellent evaporation rate, ultra-high salt-resistant, and large-scale production potential, which is expected to further promote the practical application of SVG.