Université de Neuchâtel

Influence of cationic and anionic additives on the electrical properties of ionophore-based ion-selective membranes

Morf, Werner E. ; de Rooij, Nicolaas F. ; Pretsch, Ernö

In: Journal of Electroanalytical Chemistry, 2005, vol. 581, no. 2, p. 265-274

The steady-state electrical behavior of cation-selective ionophore membranes with different kinds of ionic additives was studied on a theoretical basis. Membranes with both mobile and fixed anionic sites exhibit nonlinear current–voltage curves, which is in contrast with the ohmic behavior of pure fixed-site membranes. This can be explained from the specific concentration profiles in the...

Université de Neuchâtel

Current response of ion-selective solvent polymeric membranes at controlled potential

Sutter, Jolanda ; Morf, Werner E. ; de Rooij, Nicolaas F. ; Pretsch, Ernö

In: Journal of Electroanalytical Chemistry, 2004, vol. 571, no. 1, p. 27-35

From electrochemical measurements at the interface of two immiscible electrolytes, the current at controlled potential is usually a linear function of the ion concentration in the aqueous phase. Surprisingly, a linear relationship between the current and the logarithm of the sample ion activity is found for corresponding measurements on ion-selective electrode membranes. Here, a theoretical...