title: Kinetics of Nanoscale Self-Assembly Measured on Liquid Drops by Macroscopic Optical Tensiometry: From Mercury to Water and Fluorocarbons.
abstract: Various molecules are known to form self-assembled monolayers (SAMs) on the surface of liquids. We present a simple method of investigating the kinetics of such SAM formation on sessile drops of various liquids such as mercury, water and fluorocarbon. To measure the surface tension of the drops we used an optical tensiometer that calculates the surface tension from the axisymmetric drop shape and the Young-Laplace relation. In addition, we estimated the SAM surface coverage fraction from the surface tension measured by other techniques. With this methodology we were able to optically detect concentrations as low as tenths of ppb increments of SAM molecules in solution and to compare the kinetics of SAM formation measured as a function of molecule concentration or chain length. The analysis is performed in detail for the case of alkanethiols on mercury and then shown to be more general by investigating the case of SAM formation of stearic acid on a water droplet in hexadecane and of perfluorooctanol on a Fluorinert FC-40 droplet in ethanol.
authors.affiliation: Department of Materials Science and Engineering, Technion-Israel Institute of Technology , 32000 Haifa, Israel.|Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology , 32000 Haifa, Israel.
authors.forename: Boris
authors.initials: B
authors.lastname: Haimov
authors.affiliation: Institut für Theoretische Physik, Georg-August Universität , 37073 Göttingen, Germany.
authors.forename: Anton
authors.initials: A
authors.lastname: Iakovlev
authors.affiliation: Department of Materials Science and Engineering, Technion-Israel Institute of Technology , 32000 Haifa, Israel.
authors.forename: Rotem
authors.initials: R
authors.lastname: Glick-Carmi
authors.affiliation: Department of Materials Science and Engineering, Technion-Israel Institute of Technology , 32000 Haifa, Israel.
authors.forename: Leonid
authors.initials: L
authors.lastname: Bloch
authors.affiliation: Department of Materials Science and Engineering, Technion-Israel Institute of Technology , 32000 Haifa, Israel.
authors.forename: Benjamin B
authors.initials: BB
authors.lastname: Rich
authors.affiliation: Institut für Theoretische Physik, Georg-August Universität , 37073 Göttingen, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Müller
authors.affiliation: Department of Materials Science and Engineering, Technion-Israel Institute of Technology , 32000 Haifa, Israel.|Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology , 32000 Haifa, Israel.
authors.forename: Boaz
authors.initials: B
authors.lastname: Pokroy