Solar-Driven Freshwater Generation from Seawater and Atmospheric Moisture Enabled by a Hydrophilic Photothermal Foam
Siew‐Leng Loo, Lía Vásquez, Uttam C. Paul, Laura Campagnolo, Athanassia Athanassiou, Despina Fragouli
Abstract
with a solar-to-vapor conversion efficiency of 92.7% under 1-Sun illumination. The collected water is shown to be suitable for potable use because when synthetic seawater samples (3.5 wt %) are used, the foam is able to cause at least 99.99% of salinity reduction. The foam can also be repeatedly used in multiple hydration-dehydration cycles, consisting of moisture absorption or water collection, followed by solar-driven evaporation; in each cycle, 1 g of the foam can harvest 250-1770 mg of water. To the best of our knowledge, this is the first report of a material that integrates all the desirable properties for solar evaporation, water collection, and atmospheric-water harvesting. The lightweight and versatility of the foam suggest that the developed foams can be a potent solution for water efficiency, especially for off-grid situations.