Ionic Conductivity and Thermoelectric Power of Pure and Al2 O 3 ‐ Dispersed AgI

Ionic and electronic conductivities, and thermoelectric power have been measured for and containing a dispersion of submicron size particles. While the dispersion of enhances the ionic conductivity significantly, it does not affect the electronic properties of the matrix. The enhancement is a strong function of the size and concentration of the dispersoid. Various models have been tested to account for the enhanced conduction. However, the complex behavior of the present results points out the need for more sophisticated theoretical models. Ionic conduction and thermoelectric power data suggest that the dispersed generates an excess of cation vacancies and thereby enhances the conductivity and suppresses the thermoelectric power of the matrix. The individual heats of transport of cation interstitials and vacancies have been estimated and compared to their respective migration energies.