Measuring Ionic Conductivity in Mixed Electron-ionic Conductors Based on the Ion-blocking Method

Abstract

Ionic conductivity is common in liquid-like thermoelectric (TE) materials and it helps to understand the abnormal electrical and thermal transports. However, in experiment, accurately measuring the ionic conductivities in liquid-like TE materials is very difficult because of the very small contribution from ions to the total conductivity. In this study, based on the ion-blocking method proposed by Yokota, a home-made instrument has been built to accurately measure the ionic conductivity of liquid-like TE materials. The basic construction of this instrument and the measurement principles are introduced. The related factors that might influence the measurement accuracy are also analysed. Finally, the ionic conductivities for two typical liquid-like TE materials are presented to show the validity of our home-made instrument.