All-solid-state selective electrodes using carbon black.

This study developed new types of all-solid-state ion-selective electrodes based on carbon black (CB). The electrodes were obtained basing on two methods. The first method concerned the addition of the CB as an intermediate layer between an ionophore-doped solvent polymeric membrane and an electrical conductor. The second one used the CB as a polymeric membrane component. The stability of the electrical potential of the new solid-contact electrodes was examined by performing the current-reversal chronopotentiometry and the influence of the interfacial water film was assessed by the potentiometric aqueous-layer test. The performance of the new electrodes was evaluated by the determining K(+) with an ion-selective membrane that contained the well known valinomycin ion carrier. The new electrodes had a Nernstian slope, a high stability, the reproducibility of the standard potential values and a very small potential drift.