title: Nanobubble stability induced by contact line pinning.
abstract: The origin of surface nanobubbles stability is a controversial topic since nanobubbles were first observed. Here, we propose a mechanism that the three-phase contact line pinning, which results from the intrinsic nanoscale physical roughness or chemical heterogeneities of substrates, leads to stable surface nanobubbles. Using the constrained lattice density functional theory (LDFT) and kinetic LDFT, we prove thermodynamically and dynamically that the state with nanobubbles is in fact a thermodynamical metastable state. The mechanism consistent with the classical nucleation theory can interpret most of experimental characteristics for nanobubbles qualitatively, and predict relationships among the gas-side nanobubble contact angle, nanobubble size, and chemical potential.
authors.affiliation: Division of Molecular and Materials Simulation, State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Yawei
authors.initials: Y
authors.lastname: Liu
authors.forename: Xianren
authors.initials: X
authors.lastname: Zhang