Faculty of Medicine and Health Technology, Tampere University, Korkeakoulunkatu 3, 33720 Tampere, Finland.
Surface Science Group, Photonics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland.
Langmuir. 2021 Mar 23;37(11):3370-3381. doi: 10.1021/acs.langmuir.0c03497. Epub 2021 Mar 11.
Hierarchical surfaces that aid in the droplet nucleation, growth, and removal is highly desirable for fog and moisture harvesting applications. Taking inspiration from the unique architecture of leaf skeletons, we present a multiscale surface capable of rapidly nucleating, growing, and directional transport of the water droplets. Copper oxide microtufts were fabricated onto the leaf skeletons via electroplating and chemical oxidation techniques. The fabricated surfaces with microtufts had high wettability and very good fog harvesting ability. CuO surfaces tend to become hydrophobic over time because of the adsorption of the airborne species. The surfaces were efficient in fog harvesting even when the hydrophobic coating is present. The overall water collection efficiencies were determined, and the role of the microtufts, fractal structures, and the orientation of leaf veins was investigated. Compared to the planar control surfaces, the noncoated and hydrophobic layer-coated copper oxide microtufts on the leaf skeletons displayed a significant increase in the fog harvesting efficiency. For superhydrophilic skeleton surfaces, the water collection rate was also observed to slightly vary with the vein orientation. The CuO microtufts along with high surface area fractals allowed an effective and sustainable way to capture and transport water. The study is expected to provide valuable insights into the design and fabrication of sustainable and efficient fog harvesting systems.
具有促进液滴成核、生长和去除功能的分层表面对于雾和湿气收集应用非常理想。受叶片骨架独特结构的启发，我们提出了一种多尺度表面，能够快速实现液滴的成核、生长和定向传输。通过电镀和化学氧化技术，将氧化铜微纤维织到叶片骨架上。具有微纤维的制造表面具有高润湿性和非常好的雾收集能力。由于空气中物质的吸附，氧化铜表面随着时间的推移会变得疏水。即使存在疏水涂层，这些表面在雾收集方面仍然非常有效。我们确定了总的水收集效率，并研究了微纤维、分形结构和叶脉的方向的作用。与平面对照表面相比，叶片骨架上的非涂层和疏水层涂层氧化铜微纤维显著提高了雾收集效率。对于超亲水骨架表面，水收集速率也观察到随叶脉方向略有变化。CuO 微纤维和高表面积分形结构允许以有效和可持续的方式捕获和传输水。该研究有望为可持续和高效的雾收集系统的设计和制造提供有价值的见解。
