The Guo China-U.S. Photonics Lab , Changchun Institute of Optics, Fine Mechanics, and Physics , Changchun 130033 , China.
The Institute of Optics , University of Rochester , Rochester , New York 14627 , United States.
Langmuir. 2019 Mar 5;35(9):3562-3567. doi: 10.1021/acs.langmuir.8b04295. Epub 2019 Feb 21.
The world is facing a global issue of water scarcity where two-thirds of the population does not have access to safe drinking water. Water harvesting from the ambient environment has a potential equivalent to ∼10% of the fresh water available on the earth's surface, but its efficiency requires a special control of surface morphology. We report a novel facile physicochemical hybrid method that combines femtosecond laser structuring with hydrothermal treatment to create a surface with a well-arranged hierarchical nanoneedle structures. Polydimethylsiloxane treatment of the thus-produced hierarchical structures nurtured superhydrophobic functionality with a very low water sliding angle (∼3°) and a high water adhesion ability. About 2.2 times higher water-collection efficiency was achieved using hierarchical structures over untreated flat Ti surfaces of the same area under a given experimental condition. The comparison of water-collection behavior with other samples showed that the improved efficiency is due to the structure, and wettability induced superior water attraction and removal ability. Moreover, a uniform water condensation under low humidity (28%) is achieved, which has potential applications in harvesting water from arid environments and in high-precision drop control.
世界正面临着全球性的水资源短缺问题，有三分之二的人口无法获得安全饮用水。从环境中采集水的潜力相当于地球上表面可用淡水的 10%左右，但它的效率需要对表面形态进行特殊控制。我们报告了一种新颖的简便物理化学混合方法，该方法结合飞秒激光结构化和水热处理来创建具有良好排列的分层纳米针结构的表面。聚二甲基硅氧烷处理由此产生的分层结构培育出具有超低水滑动角（约 3°）和高水附着能力的超疏水功能。在相同实验条件下，与未经处理的平面 Ti 表面相比，使用分层结构可实现约 2.2 倍的更高集水效率。与其他样品的集水行为比较表明，效率的提高是由于结构和润湿性诱导的优越的水吸引和去除能力。此外，在低湿度（28%）下实现了均匀的冷凝水，这在从干旱环境中采集水和高精度液滴控制方面具有潜在应用。
