On Some Aspects of Nanobubble-Containing Systems

Area of Science:

• Physical Chemistry
• Nanotechnology
• Surface Science

Background:

• Bulk nanobubbles (ultrafine bubbles, UFBs) are gas bubbles <1 μm.
• Their stability and properties are not fully understood.
• Understanding UFBs is crucial for applications in various fields.

Purpose of the Study:

• Review theoretical studies on UFBs.
• Discuss models for UFB stability and formation.
• Investigate UFB interactions with liquid surfaces and solid surfaces.

Main Methods:

• Review of theoretical studies on UFBs.
• Discussion of the dynamic equilibrium model for UFB stability.
• Analysis of radical generation mechanisms during cavitation and bubble dissolution.
• Numerical simulations for radical generation and UFB behavior.

Main Results:

• The dynamic equilibrium model suggests UFBs require >50% hydrophobic surface coverage for stability.
• Hydroxide radicals (OH) are produced during cavitation and via H2O2/O3 reactions post-cavitation.
• UFBs concentrate at liquid surfaces, accelerating film rupture and reducing measured surface tension.
• Theoretical insights into UFB interactions with solid surfaces.

Conclusions:

• The dynamic equilibrium model provides a framework for UFB stability.
• UFBs play a role in radical generation and surface phenomena.
• Further research into UFB interactions is warranted for technological applications.