Zhou Xingyi, Zhao Fei, Guo Youhong, Rosenberger Brian, Yu Guihua
Materials Science and Engineering Program and Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
Lockheed Martin Corporation, 1 Lockheed Boulevard, Fort Worth, TX 76108, USA.
Sci Adv. 2019 Jun 28;5(6):eaaw5484. doi: 10.1126/sciadv.aaw5484. eCollection 2019 Jun.
Water purification by solar distillation is a promising technology to produce fresh water. However, solar vapor generation, is energy intensive, leading to a low water yield under natural sunlight. Therefore, developing new materials that can reduce the energy requirement of water vaporization and speed up solar water purification is highly desirable. Here, we introduce a highly hydratable light-absorbing hydrogel (h-LAH) consisting of polyvinyl alcohol and chitosan as the hydratable skeleton and polypyrrole as the light absorber, which can use less energy (<50% of bulk water) for water evaporation. We demonstrate that enhancing the hydrability of the h-LAH could change the water state and partially activate the water, hence facilitating water evaporation. The h-LAH raises the solar vapor generation to a record rate of ~3.6 kg m hour under 1 sun. The h-LAH-based solar still also exhibits long-term durability and antifouling functionality toward complex ionic contaminants.
通过太阳能蒸馏进行水净化是一种很有前景的生产淡水的技术。然而，太阳能蒸汽产生过程能源密集，导致在自然阳光下产水量较低。因此，开发能够降低水汽化能量需求并加速太阳能水净化的新材料是非常必要的。在此，我们介绍一种高度可水化的吸光水凝胶（h-LAH），它由聚乙烯醇和壳聚糖作为可水化骨架，聚吡咯作为光吸收剂组成，其水蒸发能耗较低（< bulk water的50%）。我们证明，提高h-LAH的水化能力可以改变水的状态并部分激活水，从而促进水的蒸发。h-LAH将太阳能蒸汽产生速率提高到了在1个太阳光照强度下约3.6 kg m⁻² h⁻¹的创纪录水平。基于h-LAH的太阳能蒸馏器对复杂离子污染物还表现出长期耐久性和抗污功能。
