Freshwater scarcity is exacerbated by uneven distribution of limited freshwater resources and high energy costs of desalination technologies.Atmospheric water vapor,a vast and geographically unrestricted reservoir,cou...Freshwater scarcity is exacerbated by uneven distribution of limited freshwater resources and high energy costs of desalination technologies.Atmospheric water vapor,a vast and geographically unrestricted reservoir,could become a sustainable alternative.Sorption-based atmospheric water harvesting(SAWH)has emerged as an available solution,yet conventional desorption methods relying on energy-intensive electrical heating hinder its scalability.Herein,a photothermal hygroscopic sponge has been developed for solar-driven atmospheric water harvesting.The composites combine a malleable melamine sponge skeleton,lithium chloride as a hygroscopic agent,and hydrangea-like molybdenum disulfide as a photothermal component,forming a multiscale“pore-film”cross-linked structure by an eco-friendly immersion-freeze-drying method.The optimized sample achieves exceptional hygroscopic capacity(3.92 g/g at 90%RH)and freshwater production efficiency(87.77%),which is attributed to synergistic effects of porous skeleton based crosslinked structures and“pore-film”structures,and outstanding photothermal conversion efficiency of MoS2.The unique structure could stabilize LiCl to prevent leakage,increase mass transfer effectiveness of whole SWAH process,and enable flexibility for diverse applications.We carried out outdoor experiments to demonstrate a solar-driven water production rate of 4.22 L m-2 d-1 without external energy input.This work provides insights into sustainable freshwater generation and promotes green energy utilization in addressing global water scarcity.展开更多
基金supported by the National Key Research and Development Program of China(No.2022YFC3702800)the National Natural Science Foundation of China(Nos.22366008,22406032)the Guizhou Provincial Basic Research Program(Natural Science)(No.ZK(2023)045).
文摘Freshwater scarcity is exacerbated by uneven distribution of limited freshwater resources and high energy costs of desalination technologies.Atmospheric water vapor,a vast and geographically unrestricted reservoir,could become a sustainable alternative.Sorption-based atmospheric water harvesting(SAWH)has emerged as an available solution,yet conventional desorption methods relying on energy-intensive electrical heating hinder its scalability.Herein,a photothermal hygroscopic sponge has been developed for solar-driven atmospheric water harvesting.The composites combine a malleable melamine sponge skeleton,lithium chloride as a hygroscopic agent,and hydrangea-like molybdenum disulfide as a photothermal component,forming a multiscale“pore-film”cross-linked structure by an eco-friendly immersion-freeze-drying method.The optimized sample achieves exceptional hygroscopic capacity(3.92 g/g at 90%RH)and freshwater production efficiency(87.77%),which is attributed to synergistic effects of porous skeleton based crosslinked structures and“pore-film”structures,and outstanding photothermal conversion efficiency of MoS2.The unique structure could stabilize LiCl to prevent leakage,increase mass transfer effectiveness of whole SWAH process,and enable flexibility for diverse applications.We carried out outdoor experiments to demonstrate a solar-driven water production rate of 4.22 L m-2 d-1 without external energy input.This work provides insights into sustainable freshwater generation and promotes green energy utilization in addressing global water scarcity.
