Veronesi Federico, Boveri Giulio, Raimondo Mariarosa
Institute of Science and Technology for Ceramics ISTEC CNR, via Granarolo, 64-48018 Faenza, Italy.
Materials (Basel). 2019 Mar 7;12(5):787. doi: 10.3390/ma12050787.
The search for surfaces with non-wetting behavior towards water and low-surface tension liquids affects a wide range of industries. Surface wetting is regulated by morphological and chemical features interacting with liquid phases under different ambient conditions. Most of the approaches to the fabrication of liquid-repellent surfaces are inspired by living organisms and require the fabrication of hierarchically organized structures, coupled with low surface energy chemical composition. This paper deals with the design of amphiphobic metals (AM) and alloys by deposition of nano-oxides suspensions in alcoholic or aqueous media, coupled with perfluorinated compounds and optional infused lubricant liquids resulting in, respectively, solid⁻liquid⁻air and solid⁻liquid⁻liquid working interfaces. Nanostructured organic/inorganic hybrid coatings with contact angles against water above 170°, contact angle with n-hexadecane (surface tension γ = 27 mN/m at 20 °C) in the 140⁻150° range and contact angle hysteresis lower than 5° have been produced. A full characterization of surface chemistry has been undertaken by X-ray photoelectron spectroscopy (XPS) analyses, while field-emission scanning electron microscope (FE-SEM) observations allowed the estimation of coatings thicknesses (300⁻400 nm) and their morphological features. The durability of fabricated amphiphobic surfaces was also assessed with a wide range of tests that showed their remarkable resistance to chemically aggressive environments, mechanical stresses and ultraviolet (UV) radiation. Moreover, this work analyzes the behavior of amphiphobic surfaces in terms of anti-soiling, snow-repellent and friction-reduction properties-all originated from their non-wetting behavior. The achieved results make AM materials viable solutions to be applied in different sectors answering several and pressing technical needs.
对水和低表面张力液体具有非润湿行为的表面的研究涉及广泛的行业。表面润湿受形态和化学特征的调节，这些特征在不同的环境条件下与液相相互作用。大多数制备拒液表面的方法都受到生物体的启发，需要制备层次结构组织的结构，并结合低表面能的化学成分。本文通过在醇类或水性介质中沉积纳米氧化物悬浮液，结合全氟化合物和可选的注入润滑液，分别形成固 - 液 - 气和固 - 液 - 液工作界面，来研究两性疏水金属（AM）和合金的设计。制备出了纳米结构的有机/无机杂化涂层，其对水的接触角大于170°，与正十六烷（20°C时表面张力γ = 27 mN/m）的接触角在140 - 150°范围内，接触角滞后小于5°。通过X射线光电子能谱（XPS）分析对表面化学进行了全面表征，而场发射扫描电子显微镜（FE - SEM）观察则可以估算涂层厚度（300 - 400 nm）及其形态特征。还通过一系列测试评估了制备的两性疏水表面的耐久性，这些测试表明它们对化学侵蚀性环境、机械应力和紫外线（UV）辐射具有显著的抗性。此外，这项工作从抗污、防雪和减摩性能方面分析了两性疏水表面的行为，所有这些性能都源于它们的非润湿行为。所取得的结果使AM材料成为适用于不同领域、满足多种紧迫技术需求的可行解决方案。
