Wilke Kyle L, Preston Daniel J, Lu Zhengmao, Wang Evelyn N
Department of Mechanical Engineering , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States.
ACS Nano. 2018 Nov 27;12(11):11013-11021. doi: 10.1021/acsnano.8b05099. Epub 2018 Oct 22.
Omniphobic surfaces based on reentrant surface structures repel all liquids, regardless of the surface material, without requiring low-surface-energy coatings. Although omniphobic surfaces have been designed and demonstrated, they can fail during condensation, a phenomenon ubiquitous in both nature and industrial applications. Specifically, as condensate nucleates within the reentrant geometry, omniphobicity is destroyed. Here, we show a nanostructured surface that can repel liquids even during condensation. This surface consists of isolated reentrant cavities with a pitch on the order of 100 nm to prevent droplets from nucleating and spreading within all structures. We developed a model to guide surface design and subsequently fabricated and tested these surfaces with various liquids. We demonstrated repellency to 10 °C below the dew point and showed durability over 3 weeks. This work provides important insights for achieving robust, omniphobic surfaces.
基于凹腔表面结构的全憎液表面能够排斥所有液体，无论表面材料如何，且无需低表面能涂层。尽管全憎液表面已被设计并展示，但在冷凝过程中它们可能会失效，而冷凝现象在自然和工业应用中都普遍存在。具体而言，当冷凝物在凹腔结构内成核时，全憎液性就会被破坏。在此，我们展示了一种即使在冷凝过程中也能排斥液体的纳米结构表面。该表面由间距约为100纳米的孤立凹腔组成，可防止液滴在所有结构内成核和扩散。我们开发了一个模型来指导表面设计，随后用各种液体制造并测试了这些表面。我们证明了在露点以下10摄氏度时仍具有排斥性，并显示出超过3周的耐久性。这项工作为实现坚固的全憎液表面提供了重要见解。
