title: Deactivation of microbubble nucleation sites by alcohol-water exchange.
abstract: The ethanol-water exchange process is one of the standard methods of generating nanobubbles at a solid-water interface. In this work, we examine whether the nanobubbles formed by the solvent exchange can initiate microbubble formation as the temperature increases, thus acting as nuclei. This, however, is not the case: the nanobubbles are stable and do not facilitate microbubble formation. Instead, the process of solvent exchange, which aids the formation of nanobubbles and even microbubbles on some hydrophobic substrates under ambient conditions, suppresses microbubble nucleation on graphite and hydrophilic micropit-decorated substrates at high temperature (i.e., deactivates the nucleation sites for microbubble formation). We ascribe this behavior to the prewetting of the surface by the alcohol and the stability of the nanobubbles to the temperature increase. The findings in this study have implications for the prevention of bubble formation for a range of applications.
authors.affiliation: Department of Chemical and Biomolecular Engineering and Particulate Fluid Processing Center, University of Melbourne, Parkville, VIC 3010, Australia. xuehuaz@unimelb.edu.au
authors.forename: Xuehua
authors.initials: X
authors.lastname: Zhang
authors.forename: Henri
authors.initials: H
authors.lastname: Lhuissier
authors.forename: Oscar R
authors.initials: OR
authors.lastname: Enríquez
authors.forename: Chao
authors.initials: C
authors.lastname: Sun
authors.forename: Detlef
authors.initials: D
authors.lastname: Lohse
mesh_terms: D000438:Alcohols / Q000737:chemistry*; D045423:Microbubbles; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D000438:Alcohols; D014867:Water