Response Time Curves of Ion-Selective Electrodes


The response characteristics of different types of ion-selective electrodes were investigated thoroughly for obtaining kinetic information for the electrode response. On the basis of response time data or supposed electrode mechanisms, the ion-selective electrodes have been divided into different groups. For the evaluation of the response time curves of electrodes, at which the rate-determining step is the diffusion of the appropriate ion in the electrode membrane phase (neutral carrier-, and covered surface electrodes), a diffusion model has been used. The response characteristics of electrodes operating on ion-exchange equilibria (e.g., precipitate based electrodes etc.) have been interpreted with the help of a first-order kinetic equation. In addition to this, a so-called multielectrode model has been worked out for the general interpretation of the electrode response if the rate determining sequence of the overall potential determining step is covered by a diffusion process through the adhering laminary layer at the electrode surface. © 1976, American Chemical Society. All rights reserved.

Publication Title

Analytical Chemistry