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Updated: Jun 17, 2026
08:02
Rendering SiO2/Si Surfaces Omniphobic by Carving Gas-Entrapping Microtextures Comprising Reentrant and Doubly Reentrant Cavities or Pillars
Published on: February 11, 2020
Scale dependence of omniphobic mesh surfaces
Shreerang S Chhatre1, Wonjae Choi, Anish Tuteja
1Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Langmuir : the ACS Journal of Surfaces and Colloids
|December 17, 2009
Summary
Researchers developed a design chart to predict apparent contact angles on textured surfaces. Smaller feature sizes improve robustness, leading to better omniphobic surfaces resistant to low surface tension liquids.
Area of Science:
- Surface Science
- Materials Science
- Fluid Dynamics
Background:
- Predicting liquid behavior on textured surfaces is crucial for designing advanced materials.
- Low surface tension liquids can destabilize composite interfaces on textured surfaces.
- Understanding the interplay between surface chemistry and topography is key to controlling wetting.
Purpose of the Study:
- To develop a design chart framework for predicting apparent contact angles on textured surfaces.
- To quantify the robustness of metastable composite interfaces against wetting.
- To investigate the influence of feature size and spacing on surface robustness.
Main Methods:
- Utilized a design chart framework correlating equilibrium contact angle and surface topography.
- Introduced a dimensionless robustness factor to assess interface stability.
- Performed contact angle measurements on dip-coated wire-mesh surfaces with controlled cylindrical textures.
Main Results:
- A design chart was established to predict apparent contact angles based on surface properties.
- Identified a critical pressure difference for the transition from metastable to fully wetted interfaces.
- Demonstrated that smaller feature sizes (smaller R) enhance robustness for omniphobic surfaces.
Conclusions:
- The design chart provides a predictive tool for engineering textured surfaces with desired wetting properties.
- Surface topography, particularly feature size, significantly impacts the robustness of liquid repellency.
- Optimal design for omniphobicity involves minimizing feature size for enhanced resistance to low surface tension liquids.
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