Department of Mechanical Engineering, The University of Hong Kong, Hong Kong; HKU-Zhejiang Institute of Research and Innovation (HKU-ZIRI), Hangzhou, Zhejiang 311300, China.
Department of Mechanical Engineering, The University of Hong Kong, Hong Kong; HKU-Zhejiang Institute of Research and Innovation (HKU-ZIRI), Hangzhou, Zhejiang 311300, China.
J Colloid Interface Sci. 2021 Jan 1;581(Pt B):545-551. doi: 10.1016/j.jcis.2020.07.153. Epub 2020 Aug 3.
As an effective strategy to alleviate the global water shortage, the Janus membrane has been widely developed to harvest the fog droplets because of its advantages of timely drainage and directional droplet delivery. However, Janus membrane is extremely susceptible to the direction of the fog stream, which changes dynamically in nature. In this work, we develop a three-layer sandwiched fog collector consisting of a hydrophilic inner mesh and two superhydrophobic outer meshes, which always serves as a Janus collector to enable a stable and efficient fog collection independent of the direction of the mist stream. We also demonstrate the superiority of such sandwiched fog collector in terms of the droplet shedding size and onset time, as well as the directional droplet delivery. The droplet coalescence effectively facilitates the shedding of the attached droplets on the outer superhydrophobic mesh, and the directional delivery of the clogged droplets from the superhydrophobic to hydrophilic layer further dries the mesh surface for the successive interception of fog droplets. These mechanisms can work together seamlessly, which benefits the productive collection of the droplet of different sizes on the three-layer sandwiched fog collector.
作为缓解全球水资源短缺的有效策略，Janus 膜因其及时排水和定向液滴输送的优势而被广泛开发用于收集雾滴。然而，Janus 膜对雾流的方向极其敏感，雾流在自然界中是动态变化的。在这项工作中，我们开发了一种由亲水内网和两个超疏水外网组成的三层夹心式雾收集器，它始终作为 Janus 收集器，能够稳定、高效地收集雾，而不受雾流方向的影响。我们还展示了这种夹心式雾收集器在液滴脱落尺寸和开始时间以及定向液滴输送方面的优势。液滴聚结有效地促进了附着在外部超疏水网的液滴的脱落，堵塞的液滴从超疏水到亲水层的定向输送进一步干燥了网面，以便连续拦截雾滴。这些机制可以协同工作，有利于在三层夹心式雾收集器上收集不同尺寸的液滴。
