Electrode potential in suspensions interpreted as a mixed potential
Year: 2015
Type: article
Abstract: A simple experimental method was developed and applied to establish and alter the mixed potential of a measurement electrode in a galvanic cell. The electrode, immersed simultaneously in two different contacting solutionsforming a sharp boundary, alters its mixed potential when moved in regard to the boundary, because at the same time inhibition of the electrode reactions changes. Illustrative experiments were made with a Cu electrode in CuSO 4 solutions. Using the same method the electrode potential behaved quite analogously when the electrode was dipped simultaneously in an equilibrium solution and in the sediment of a suspension composing a galvanic cell. This similarity allows interpretation of the potential of the electrode as the mixed potential when it is dipped in a suspension. By bringing the electrode into contact with charged particles, their double layers overlap and form sporadic contact regions, where the electrochemical potential of the potential determining ions is different from that in the surrounding equilibrium solution. Therefore two different electrochemical reactions can take place on the surface of the same electrode, which is the condition for the appearance of the mixed potential.
Author: Oman, Srečko
Language: English
Subfield: Physical and Theoretical Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2469617182