IMPEDANCE STUDIES OF THE CELL AG/AGI/AG-BETA''-ALUMINA/AGI/AG

The construction of the cell Ag/AgI/Ag β″-alumina/AgI/Ag is described. The impedance of this cell was measured between 10-3 and 104 Hz at temperatures between 20 and 550°C. At temperatures below 100°C the cell impedance is determined to a large extent by the bulk resistance of the AgI layer and to a smaller extent by the impedance of the interface Ag/AgI. At temperatures between 160 and 350°C the impedance is controlled by the bulk resistance of the Ag β-alumina and an impedance due to contact problems between Ag and AgI. The bulk resistance of the β″-alumina becomes predominant between 350 and 550°C. A hindrance due to the transfer of silver ions from AgI to Ag β″-alumina was not observable in the whole temperature range.