Original scientific paper

Electrical Double Layer on Silver Iodide and Overcharging in the Presence of Hydrolyzable Cations

Johannes Lyklema ; Department of Physical Chemistry and Colloid Science, Wageningen University, Wageningen, Netherlands
Tatiana Golub ; Department of Colloid Chemistry, St. Petersburg University, St. Petersburg, Russia

Abstract

Previous studies on the surface charge and electrokinetic charge on silver iodide as a function of the pAg in the presence of some monovalent and trivalent cations as the counterions were extended to include the influence of pH. The main reason for this study was to investigate the possible propensity of overcharging by adsorption of hydrolyzed counterions. It was found that for K+ as the counterion the double layer properties could be well represented in terms of a simple Gouy-Stern model, without accounting for hydrolysis. However, with Al3+ or La3+ as the counterions, adsorption of hydrolyzed species takes place when the pH is high enough, leading to electrokinetic charge reversal.

Keywords

electrical double layer; silver iodide; surface charge; overcharging; charge reversal; hydrolysis at interfaces

Hrčak ID:

18255

URI

https://hrcak.srce.hr/18255

Publication date:

30.11.2007.

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