Molecular Mechanisms of Solvation Force for Aqueous Systems

Area of Science:

• Physical Chemistry
• Surface Science
• Nanotechnology

Background:

• Solvation force, driven by interfacial liquid structure, governs short-range interactions in fields like batteries and colloids.
• Existing contact value theories underestimate aqueous solvation force due to simplifying assumptions.

Purpose of the Study:

• To develop a parameter-free theoretical expression for solvation force on atomically smooth surfaces.
• To quantitatively relate solvation force to the energy barrier of liquid molecule expulsion from confinement.
• To investigate the influence of temperature and surface wetting properties on solvation force.

Main Methods:

• Theoretical modeling inspired by liquid flow fields under confinement.
• Quantitative relation of solvation force to an energy barrier.
• Experimental validation using three-dimensional atomic force microscopy (3D-AFM).

Main Results:

• A novel parameter-free expression for solvation force was derived.
• Temperature and surface wetting significantly affect solvation force curves.
• Experimental data from hydrophilic to hydrophobic surfaces validated the theoretical predictions.

Conclusions:

• The proposed model provides a more accurate quantitative understanding of aqueous solvation force.
• The energy barrier for liquid expulsion is a more intrinsic property than liquid density in confinement.
• This work advances the understanding of interfacial phenomena crucial for nanotechnology and materials science.