Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 60: Solid-Liquid Interfaces: Structure, Spectroscopy, Reactions and Electrochemistry
O 60.2: Poster
Tuesday, March 21, 2017, 18:30–20:30, P2-OG2
Overcharging and charge reversal of surface charge in high electrolyte concentrations — •Christine Klinger, Markus Valtiner, and Christian Weber — Institut für physikalische Chemie, Fakultät für Chemie und Physik, Technische Universität Bergakademie, Freiberg, Deutschland
The structure of water and ions in the electric double layer influences adhesion and reactivity at solid/liquid interfaces. Previous investigation showed the suitability of atomic force microscopy (AFM) for the investigation of electric double layer structures, based on molecularly resolved force spectroscopy and imaging with atomic resolution. Using the AFM, we quantitatively measure the effect of overcharging and charge reversal of surface charge on mica due to the condensation of Cs-ions into the mica lattice. We examine the surface charge at mica applying different concentrations of aqueous CsCl solution with ionic strengths ranging from 10 mM to 100 mM. Thereby we can show that mica surfaces overcharging leading to a charge reversal in high electrolyte concentrations. In detail, our results provide an insight into the interaction forces and electric double layer structures depending on different environmental conditions.