http://experimentationlab.berkeley.edu/sites/default/files/AFMImages/butt_AFM.pdf

Force measurements with the atomic force microscope: Technique, interpretation and applications

http://kbose.weebly.com/uploads/1/0/4/9/10492046/force-distance_curves_by_atomic_force_microscopy_1.pdf

Force-distance curves by atomic force microscopy

Effect of solution chemistry on the surface charge of polymeric reverse osmosis and nanofiltration membranes

http://www.oocities.org/santanuparia/research/pdf/acis-04.pdf

A review on experimental studies of surfactant adsorption at the hydrophilic solid-water interface.

The recently published points of zero charge of metal oxides and related materials are compiled to update the previous compilation. The purity of materials is the most important factor responsible for discrepancies in the literature data. In contrast to the success of new spectroscopic methods in the studies of specific adsorption, the progress in studies of primary surface charging of oxides over recent years is less spectacular.

The pH-dependent surface charging and the points of zero charge.

Zeta potential measurement of muscovite mica basal plane-aqueous solution interface by means of plane interface technique

The effect of aqueous KBr concentration on the electrical double layer properties of two types of self-assembled hexadecyltrimethylammonium bromide (CTAB) surfaces has been investigated. A solvatochromic acid-base indicator has been used to determine the surface potential (ψ 0 ) of CTAB micelles. Three different techniques have been employed to examine self-assembled CTAB bilayers adsorbed on amorphous silica surfaces. Flat plate streaming potentials (ζ s potentials), electrostatic potentials obtained from the electrophoretic mobility of relatively large colloid spheres (ζ e potentials), and diffuse layer potentials (ψ d ) derived from the force versus separation curves for the interaction of a colloid sphere with a flat plate (measured with an atomic force microscope) have been analyzed. ζ s and ζ e potentials were found to be equivalent over a wide range of aqueous KBr concentration. ψ d values in accord with ζ s and ζ e potentials were only derived in CTAB systems with a relatively low KBr concentration. At relatively high KBr concentrations (> 10 -3 mol dm -3 ), ψ d values were less than ζ s and ζ e potentials. This discrepancy has been attributed to the influence of surface roughness on the AFM force curve analysis. Micellar ψ 0 values were larger than ζ potentials. Analyses in terms of classical electrical double layer theory suggest that the degree of counterion dissociation from the surfactant headgroups (α) is markedly different for highly curved and planar surfaces ; α is in the range 0.05-0.11 for the adsorbed CTAB bilayers and in the range 0.29-0.43 for spherical CTAB micelles. Air/water surface tension curves have been employed to illustrate the effect that KBr has on minimum area per CTAB molecule at a planar interface and to provide values for the critical micelle concentration as a function of KBr concentration. CTAB micelles behave as Nernstian objects in KBr solution with the surfactant monomer acting as the potential determining ion. On the basis of this Nernstian behavior, a simple method has been employed to calculate the hydrophobic contribution to the free energy of CTAB micellization.

Comparison of Techniques for Measuring the Electrical Double Layer Properties of Surfaces in Aqueous Solution: Hexadecyltrimethylammonium Bromide Self-Assembly Structures as a Model System

The muscovite mica basal plane surface was investigated directly with atomic force microscopy (AFM), zeta potential, and contact angle measurements after H + , Li + , K + , and Mg 2+ ion exchange followed by heating at a temperature of 300 o C. Typical AFM images of the H- and K-mica showed an ideal array of light spots corresponding to one to five oxygen ions on the surface crystallographic layer of the muscovite mica. No spots were observed in the cavity surrounded by the light spots. In particular, the ideal image of H-mica, which should correspond to a bare basal plane where no interlayer cation exists, indicated that the calcination did not damage the mica basal plane

Molecular-Scale Structure of the Cation Modified Muscovite Mica Basal Plane

The muscovite mica-electrolyte interface was investigated using an electrokinetic (electro-osmosis) technique after ion exchange and low temperature calcination at 300 o C. Samples calcined after ion exchange with H + and K + showed similar electrokinetic properties to the freshly cleaved sample whereas those calcined after ion exchange with either Li + or Mg 2+ ions showed a significant reduction in the magnitude of the zeta potential. This reduction was attributed to an irreversible fixation during calcination of Li + and Mg 2+ ions respectively to the basal plane of the muscovite mica. Modeling of the electrical double layer properties using a Gouy-Chapman-Stern-Grahame approach indicated that greater than 90% of the charge in the lattice had been neutralized by the calcination procedure

Cationic modification of muscovite mica : an electrokinetic study

Highly ordered parallel alignment of a synthetic clay, referred to herein as an expandable mica (ME) but similar in behavior and physical characteristics to montmorillonite, in sodium tripolyphosphate (STP) solutions has been observed by an X-ray diffraction method. The weight ratio of the clay was 7%, and the ME/STP by weight ratio was varied from 0.1 to 0.4. The X-ray diffraction patterns of the suspensions at high STP concentrations were very sharp, and the basal reflections of the clay gave up to fifth order reflections in some samples. The basal spacing of the clay in the suspensions decreased from 8.70 to 4.82 nm with increasing STP concentrations. The rheological properties of the same suspensions showed nonNewtonian behavior at zero STP addition. The steady shear viscosity of the suspensions decreased dramatically with increasing STP addition at a given shear rate. The total potential energy for particleparticle interaction calculated using classical DLVO theory indicates that the clay particles fall into a secondary minimum and that phosphate anions play an important role in controlling the alignment of the platelets.

Satoshi Nishimura

Papers

Zeta potential measurement of muscovite mica basal plane-aqueous solution interface by means of plane interface technique

Comparison of Techniques for Measuring the Electrical Double Layer Properties of Surfaces in Aqueous Solution: Hexadecyltrimethylammonium Bromide Self-Assembly Structures as a Model System

Molecular-Scale Structure of the Cation Modified Muscovite Mica Basal Plane

Cationic modification of muscovite mica : an electrokinetic study

X-ray diffraction and rheology study of highly ordered clay platelet alignment in aqueous solutions of sodium tripolyphosphate