| Nanoscale gas bubbles (interfacial nanobubbles) can be produced on a hydrophobic surface in contact with water and stay for several days. The existence of these nanobubbles can have significant influence on a range of interfacial phenomena. For example, they may facilitate the long-ranged interactions between surfaces, give rise to hydrodynamic slip on the boundary, initiate the rupture of thin liquid films, and prevent the adsorption of particles or proteins onto the interfaces. However, the mechanism behind the lifetime of nanobubbles still remains elusive. Given their tiny volume, one would expect they should disappear in microseconds. By using atomic force microscopy to follow the morphology of nanobubbles with time in partially degassed water, we found that the boundary of nanobubbles is pinned and the loss of the bubble volume is mainly achieved by the decrease of the bubble height. The pinning may have played an important role in the long lifetime of nanobubbles as well as their superstability to the temperature rise. This talk will cover the response of nanobubbles to the temperature close to the boiling point of water, gentle ultrasound and substantial pressure drop, respectively, and will also cover the stability of surface nanodroplets.
|
| Professor of University of Twente, The Netherlands. Her research interest includes colloid and interface science and nanomaterials. She has published more than 80 peer reviewed scientific papers including PNAS, PRL, JACS, ANGEW CHEM INT EDIT, ACS Nano etc (Total citations > 2350; h-index = 24). Prof. Zhang serves as an associate editor of The European Physical Journal E.
|