Materials Science and Engineering Program and Department of Mechanical Engineering, The University of Texas at Austin, TX, 78712, USA.
School of Physics Science & Technology and Jiangsu Key Laboratory for NSLSCS, Nanjing Normal University, Nanjing, 210023, China.
Adv Mater. 2019 Mar;31(10):e1806446. doi: 10.1002/adma.201806446. Epub 2019 Jan 11.
Atmospheric water harvesting (AWH)-producing fresh water via collecting moisture from air-enables sustainable water delivery without geographical and hydrologic limitations. However, the fundamental design principle to prepare materials that can convert the water vapor in the air to collectible liquid water is still mostly unknown. Here, a super moisture-absorbent gel, which is composed of hygroscopic polypyrrole chloride penetrating in hydrophilicity-switchable polymeric network of poly N-isopropylacrylamide, is shown. Based on such design, a high-efficiency water production by AWH has been achieved in a broad range of relative humidity. The synergistic effect enabled by the molecular level integration of hygroscopic and hydrophilicity-switchable polymers in a network architecture presents controllable interaction between the gel and water molecules, simultaneously realizing efficient vapor capturing, in situ water liquefaction, high-density water storage and fast water releasing under different weather conditions. Being an effective method to regulate migration of water molecules, such design represents a novel strategy to improve the AWH, and it is also fundamental to other water management systems for environmental cooling, surficial moisturizing and beyond.
大气水收集（AWH）——通过从空气中收集水分来生产淡水——能够在没有地理和水文限制的情况下实现可持续的供水。然而，制备能够将空气中的水蒸气转化为可收集液态水的材料的基本设计原则在很大程度上仍然未知。在这里，展示了一种由吸水性聚吡咯氯化物渗透在亲水性可切换聚合物网络的聚 N-异丙基丙烯酰胺组成的超吸水性凝胶。基于这种设计，在很宽的相对湿度范围内，通过 AWH 实现了高效的水生产。在网络结构中，吸湿性和亲水性可切换聚合物的分子水平集成所产生的协同效应，实现了凝胶与水分子之间的可控相互作用，同时在不同的天气条件下实现了高效的蒸汽捕获、原位水液化、高密度水存储和快速水释放。作为一种有效调节水分子迁移的方法，这种设计代表了一种改进 AWH 的新策略，对于环境冷却、表面保湿等其他水管理系统也具有基础性意义。
