Universal Gas Adsorption Mechanism for Flat Nanobubble Morphologies

Area of Science:

• Thermodynamics
• Surface Science
• Nanotechnology

Background:

• Interfacial nanobubbles are crucial in various physical and chemical processes.
• The solid-gas interface energy significantly impacts nanobubble morphology and stability.
• Understanding these effects is key to controlling nanobubble behavior.

Purpose of the Study:

• To develop a simple thermodynamic model for gas adsorption at the solid-gas interface.
• To investigate the influence of gas adsorption on interfacial nanobubble morphology.
• To determine the effect of adsorption on nanobubble stability and lifetime.

Main Methods:

• Development of a thermodynamic model incorporating gas adsorption.
• Analysis of the model's predictions for nanobubble shape and contact angle.
• Comparison of model results with existing experimental data.

Main Results:

• The thermodynamic model predicts flatter nanobubble shapes due to gas adsorption.
• Gas adsorption leads to reduced gas-side contact angles compared to the zero-adsorption case.
• The observed effects are consistent across both hydrophilic and hydrophobic substrates.

Conclusions:

• Gas adsorption at the solid-gas interface is a key factor influencing nanobubble morphology.
• The model demonstrates that adsorption stabilizes nanobubbles, prolonging their existence.
• These findings have implications for controlling nanobubble behavior in various applications.