The effective interfacial tensions between pure liquids and rough solids: a coarse-grained simulation study.

Area of Science:

• Materials Science
• Computational Chemistry
• Surface Science

Background:

• Understanding solid-liquid interfacial tension (SL-IFT) is crucial for various applications.
• Surface roughness is known to influence interfacial properties, but its precise impact on SL-IFT requires detailed investigation.

Purpose of the Study:

• To investigate the effect of surface roughness on effective solid-liquid interfacial tension (SL-IFT) using simulations.
• To quantify the relationship between Wenzel's roughness factor and effective SL-IFT.
• To analyze the influence of solid-liquid repulsion strength on SL-IFT in the presence of surface roughness.

Main Methods:

• Coarse-grained simulations employing the dissipative particle dynamics (DPD) method.
• Designing explicit solid-liquid interfaces with varying degrees of surface roughness.
• Characterizing solid surface roughness using Wenzel's roughness factor.

Main Results:

• Effective SL-IFT increases with increasing surface roughness (Wenzel's roughness factor).
• Surface roughness alters the liquid's molecular structure near the solid interface.
• Effective SL-IFT is directly proportional to the solid-liquid repulsion strength.

Conclusions:

• Increased surface roughness leads to more effective solid-liquid interactions, raising SL-IFT.
• The interplay between surface roughness and solid-liquid repulsion strength significantly affects interfacial properties.
• Simulation insights provide a deeper understanding of how surface topography influences liquid behavior at interfaces.