Cavitation nuclei and surface nanobubbles -- the model of non-adsorbed interfacial liquid zones

A theory of bubble nuclei at water-solid interfaces is presented, based on non-adsorbed interfacial liquid zones (NAILZ). It explains the low contact angle of surface nanobubbles, observed at clean solid surfaces submerged in purified water from the H-O-H angle of the water molecule. H$_2$O molecules which mirror-hydrogen bond to the solid, and remaining alien polar molecules create the bubble surface. When plain water is used, non-polar alien molecules prevent the low-angle bubble formation, but not the NAILZ formation. It gives a key to understanding interfacial bubble nuclei generally, surface nanobubbles as well as cavitation nuclei on natural solid surfaces.