Towel-Inspired Fabric-Based Evaporator for Highly Efficient Water-Evaporation Desalination

Solar-driven interfacial evaporation is an environmentally friendly and sustainable freshwater-production technology with substantial market potential. Nonetheless, it encounters significant challenges related to energy-conversion efficiency and resistance to salt crystallization. Thus, a towel-inspired fabric-based evaporator (TFE) containing various functional layers using carbon and cotton-polyester-blended fibers is designed and woven. The surface of the TFE is woven into a towel-ring structure, which affords a high sunlight-contact area and a superior sunlight absorption rate of 96.2%. In contrast, the hydrophilic layer at the bottom of the TFE delivers superior water-molecule storage and conduction due to its multilayer corner-interlocking fabric structure. Compared to commercial fabric-based evaporators, the loop structure of the towel fabric enables water molecules to flow rapidly under the influence of wind, which effectively enhances the evaporation rate of the TFE. The optimal TFE can reach a high water-evaporation rate of 3.72 kg m-2 h-1 under 1 kW m-2 sunlight and a wind speed of 2 m s-1, which is ascribable to sunlight/wind synergy. No precipitated salt is detected on the TFE surface after continuously evaporating a 3.5 wt.% NaCl solution for 8 h. These exceptional attributes position the TFE as a highly suitable candidate for diverse seawater desalination applications. A towel-inspired fabric-based evaporator (TFE) containing various functional layers using carbon and cotton-polyester-blended fibers is designed and woven as a towel-ring structure. Compared to commercial fabric-based evaporators, the optimal TFE not only can reach a high water-evaporation rate of 3.72 kg m-2 h-1 under 1 kW m-2 sunlight and a wind speed of 2 m s-1, but also achieve long-term desalination even after continuously evaporating a 3.5 wt.% NaCl solution for 8 h.image

Automated summary

This study presents the design and fabrication of a towel-inspired fabric evaporator that addresses the challenges of solar-driven interfacial evaporation, such as energy-conversion efficiency and resistance to salt crystallization. The fabric evaporator exhibits a high sunlight absorption rate and excellent evaporation rate, making it suitable for various seawater desalination applications.