Influence of solid electrolyte upon the repeatability and reproducibility of all-solid-state ion-selective electrodes with inorganic insertion material paste

Abstract

The effects of the solid electrolyte β”-alumina upon the electrode responses of all-solid-state ion-selective electrodes (ISEs) with the inorganic insertion material Na0.33MnO2 were examined for Na+-ISE and K+-ISE. β”-alumina was added into the Na0.33MnO2 paste as a Na+-supply source for the ion-to-electron transducer Na0.33MnO2. For K+-ISE in the absence of β”-alumina, the insertion ion from Na0.33MnO2, Na+, was not identical to the target ion, K+, in the K+-selective membrane; thus, the exchange of Na+ for K+ at the Na0.33MnO2 | selective-membrane interface caused significant potential drift of K+-ISE; however, this drift was suppressed by the addition of β”-alumina into the Na0.33MnO2 paste. The obtained potential repeatability and Eo reproducibility (± 1.0 mV) for K+-ISE were made similar to those for Na+-ISE with Na0.33MnO2; these results show that all-solid-state ISEs can be developed for various ions without changing the inorganic insertion material.