Anisotropic Wettability on One-Dimensional Nanopatterned Surfaces: The Effects of Intrinsic Surface Wettability and Morphology

Abstract

Large-scale molecular dynamic simulations were conducted to study anisotropic wettability on one-dimensional (1D) nanopatterned surfaces. Hexadecane (C 16 H 34 ) and decane (C 10 H 22 ) nanodroplets were used as wetting liquids. Initially, surfaces with various intrinsic wettability (oleophobic and oleophilic) were produced using surface lattice size as a control parameter. These surfaces were subsequently patterned with 1D grooves of different sizes, and their anisotropic wettability was examined. The results show that anisotropic wettability strongly depends on intrinsic surface wettability and surface morphology. The results also demonstrate that the anisotropy in the contact angle is negligible for oleophobic surfaces. However, the anisotropy becomes more evident for oleophilic surfaces and increases with the degree of oleophilicity. Results suggest that anisotropy also depends on the surface morphology, including the patterns' width and height. Monitoring the droplet shape showed that more significant droplet distortion was associated with higher anisotropy. A clear association was lacking between the roughness ratio, r, and the degree of anisotropy. The observed average contact angle for 1D patterned oleophilic surfaces disagreed with the predicted values from the Wenzel theory. However, the theory could correctly predict the state of the droplet being Cassie−Baxter or Wenzel.

Effect of surface treatment and shear flow on biofilm formation over materials employed in space water storage and distribution systems

“…This occurs due to the fact that groove walls function as pinning points, providing additional support with the surface tension. As a result, the contact angles were larger when observing the droplet from the direction of the grooves (Park et al, 2021). It should be mentioned here that not only the wettability of a surface could affect the biofilm formation, but also the biofilm formation could impact the wetting characteristics of a surface (Recupido et al, 2020;Castigliano et al, 2021;Kampouraki et al, 2022;Recupido et al, 2022;Recupido et al, 2023).…”

Manipulating the Switching of Liquid Crystals by Interfacial Nanotips Penetrating Polyimide Hybrid Alignment Layers

“…34,35 Nanoconical surface topology is significant to align LCs in their preferred dimensional orientations and therefor accelerates or weakens the electrical switch of LCs by modified surface anchoring. 36,37 In this research, the alignment and electro-optical switch of LCs that are sandwiched between hybrid thin layers in the twist nematic (TN) mode and electrically controller birefringence (ECB) mode were investigated to see how LCs were modulated by nanotips. Alignment of LCs in the TN mode was characterized and captured using POM as shown in Figure 5.…”

Application of Surface Wettability to Control Spreading of an Impacting Droplet

“…Aluminum sheets (AA 6061, 25 mm × 75 mm × 1.5 mm, from McMaster-CARR) were selected for testing as a commonly used material in the industry. Numerous studies have investigated methods for modifying the wettability of solid substrates by changing the chemical and/or morphological characteristics of the surface. − In this study, we developed an efficient and feasible method to create a patterned surface with a singular tunable wettability contrast for various impact conditions. This contrast was achieved by coating two types of self-assembled monolayers (SAM), using a dipping method with trichloro-octylsilane (OT, CH 3 (CH 2 ) 7 SiCl 3 , 97%, from Sigma-Aldrich) and trichloro-octadecylsilane (OD, CH 3 (CH 2 ) 17 SiCl 3 , 85%, from Fisher Scientific).…”