Electronic conduction in AgI(Al 2O 3) composites

Abstract

The effect of dispersions of submicron size Al 2O 3 particles on the electronic conduction of α-AgI and β-AgI have been studied using Wagner's polarization method. Samples with Al 2O 3 contents between 0 and 40 mol% have been prepared. The electronic conduction is due in general to excess electrons for polarization potentials up to about 0.4 V and to electron holes for higher polarization potentials. Increasing contents of Al 2O 3 dispersions in the α-AgI induce a moderate enhancement of the excess electron conductivity σ 0 e, but affects very little the hole conductivity, σ 0 h. For the β-AgI modification the enhancement of both σ 0 e and σ 0 h is considerable. Nevertheless, the absolute values of σ 0 e and σ 0 h remain in all the cases negligible in comparison to the ionic conductivity of these compounds.