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 (NAILZs). 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. H₂O molecules that 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.