Thermodynamic Stability of Nanobubbles

Phil Attard

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arXiv · 1503.04365

Thermodynamic Stability of Nanobubbles

Phil Attard

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Abstract

The observed stability of nanobubbles contradicts the well-known result in classical nucleation theory, that the critical radius is both microscopic and thermodynamically unstable. Here nanoscopic stability is shown to be the combined result of two non-classical mechanisms. It is shown that the surface tension decreases with increasing supersaturation, and that this gives a nanoscopic critical radius. Whilst neither a free spherical bubble nor a hemispherical bubble mobile on an hydrophobic surface are stable, it is shown that an immobilized hemispherical bubble with a pinned contact rim is stable and that the total entropy is a maximum at the critical radius.

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Phil Attard. 2015-03-15. Thermodynamic Stability of Nanobubbles. https://arxiv.org/abs/1503.04365

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