Electrical conduction of superionic conductors: Na2ZrO3

Abstract

Measurement of the thermoelectric power (S) and electrical conductivity (σ) of Na2ZrO3 is reported from 450K to nearly the melting point. The log σT and S versus T−1 plots are linear in some temperature range with different slopes. They show two distinct regions, one corresponding to superionic phase and the other to normal phase. In the superionic phase, Na+ ions are the main entity of charge carriers and Paddle wheel mechanism suitably explains the transport mechanism. In the normal phase, the conduction is mainly due to the Frenkel defect. The enthalpy for migration and heat of transport have also been evaluated in both normal and superionic phases of the compound.