title: Dynamic equilibrium mechanism for surface nanobubble stabilization.
abstract: Recent experiments have convincingly demonstrated the existence of surface nanobubbles on submerged hydrophobic surfaces. However, classical theory dictates that small gaseous bubbles quickly dissolve because their large Laplace pressure causes a diffusive outflux of gas. Here we suggest that the bubbles are stabilized by a continuous influx of gas near the contact line, due to the gas attraction towards hydrophobic walls [Dammer and Lohse, Phys. Rev. Lett. 96, 206101 (2006); 10.1103/PhysRevLett.96.206101Zhang, Phys. Rev. Lett.10.1103/PhysRevLett.98.136101 98, 136101 (2007); 10.1103/PhysRevLett.98.136101Mezger, J. Chem. Phys. 128, 244705 (2008)10.1063/1.2931574]. This influx balances the outflux and allows for a metastable equilibrium, which, however, vanishes in thermodynamic equilibrium. Our theory predicts the equilibrium radius of the surface nanobubbles, as well as the threshold for surface nanobubble formation as a function of hydrophobicity and gas concentration.
authors.affiliation: School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Brenner
authors.forename: Detlef
authors.initials: D
authors.lastname: Lohse