title: AFM characterization of nanobubble formation and slip condition in oxygenated and electrokinetically altered fluids.
abstract: Nanobubbles are gas-filled features that spontaneously form at the interface of hydrophobic surfaces and aqueous solutions. In this study, an atomic force microscope (AFM) was used to characterize the morphology of nanobubbles formed on hydrophobic polystyrene (PS) and octadecyltrichlorosilane (OTS) films immersed in DI water, saline, saline with oxygen and an electrokinetically altered saline solution produced with Taylor-Couette-Poiseuille flow under elevated oxygen pressure. AFM force spectroscopy was used to evaluate hydrodynamic and electrostatic forces and boundary slip condition in various fluids. The effect of solution, electric field and surface charge on shape, size and density of nanobubbles as well as slip length was quantified and the results and underlying mechanisms are presented in this paper.
authors.affiliation: Nanoprobe Laboratory for Bio- & Nanotechnology and Biomimetics (NLBB), The Ohio State University, 201 W. 19th Ave., Columbus, OH 43210, USA. Electronic address: bhushan.2@osu.edu.
authors.forename: Bharat
authors.initials: B
authors.lastname: Bhushan
authors.affiliation: Nanoprobe Laboratory for Bio- & Nanotechnology and Biomimetics (NLBB), The Ohio State University, 201 W. 19th Ave., Columbus, OH 43210, USA; School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, PR China.
authors.forename: Yunlu
authors.initials: Y
authors.lastname: Pan
authors.affiliation: Nanoprobe Laboratory for Bio- & Nanotechnology and Biomimetics (NLBB), The Ohio State University, 201 W. 19th Ave., Columbus, OH 43210, USA.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Daniels
mesh_terms: D055664:Electrochemical Techniques; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D011137:Polystyrenes; D012821:Silanes; D014867:Water; C061189:octadecyltrichlorosilane; D010100:Oxygen