Effect of iodide addition on the ionic conduction in silver metaphosphate glasses

The glass forming regions of MIn-AgPO3 (M=Li, Na, K, Rb, Cs and Tl for n=1, M=Cd for n=2 and M=Bi for n=3) systems were determined. The glass transition temperature, density and ionic conductivity for these glasses were investigated. The increase of ionic conductivity was obtained with increasing iodide content in all the glasses examined in the present investigation. Ionic conductivity was distinguished by the difference of valence of M ion. It was found that isothermal conductivity and activation energy for MIn-AgPO3 glasses are mainly affected by iodine ion concentration. It is considered that ion exchange between M and Ag ions occurs in the glass and then Ag ions contiguous with iodine ions tend to move in the gateway formed by iodine ions and phosphate chains.