Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, 08544, USA.
Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, NJ, 08544, USA.
Adv Mater. 2021 May;33(18):e2007833. doi: 10.1002/adma.202007833. Epub 2021 Mar 31.
The global demand for clean and safe water will continue to grow well into the 21st century. Moving forward, the lack of access to clean water, which threatens human health and strains precious energy resources, will worsen as the climate changes. Therefore, future innovations that produce potable water from contaminated sources must be sustainable. Inspired by nature, a solar absorber gel (SAG) is developed to purify water from contaminated sources using only natural sunlight. The SAG is composed of an elastic thermoresponsive poly(N-isopropylacrylamide) (PNIPAm) hydrogel, a photothermal polydopamine (PDA) layer, and a sodium alginate (SA) network. Production of the SAG is facile; all processing is aqueous-based and occurs at room temperature. Remarkably, the SAG can purify water from various harmful reservoirs containing small molecules, oils, metals, and pathogens, using only sunlight. The SAG relies on solar energy to drive a hydrophilic/hydrophobic phase transformation at the lower critical solution temperature. Since the purification mechanism does not require water evaporation, an energy-intensive process, the passive solar water-purification rate is the highest reported. This discovery can be transformative in the sustainable production of clean water to improve the quality of human life.
到 21 世纪，全球对清洁和安全用水的需求仍将持续增长。随着气候变化，缺乏清洁水的问题将更加严重，这不仅威胁到人类健康，还会严重消耗宝贵的能源资源。因此，未来必须创新，开发出可持续的技术，从污染水源中生产饮用水。受自然启发，研究人员开发了一种太阳能吸收凝胶（Solar Absorber Gel，SAG），仅利用自然阳光即可从污染水源中净化水。SAG 由弹性热响应性聚（N-异丙基丙烯酰胺）（PNIPAm）水凝胶、光热聚多巴胺（PDA）层和海藻酸钠（SA）网络组成。SAG 的生产方法简单，所有加工过程均为水性且在室温下进行。值得注意的是，SAG 仅利用阳光，就可以从小分子、油、金属和病原体等各种有害物质的储层中净化水。SAG 依靠太阳能驱动低临界溶液温度下的亲水性/疏水性相转变。由于净化机制不需要水蒸发这一能源密集型过程，因此被动太阳能水净化速度是目前报道的最高速度。这一发现可以改变清洁水的可持续生产方式，提高人类生活质量。
