DC conductivity and polarisation in iron phosphate glasses

Thermally stimulated polarisation (TSPC) and depolarisation current (TSDC) techniques were used to study polarisation and conduction in xFe(2)O(3)(100-x)P2O5, (14 less than or equal to x less than or equal to 47) glasses. TSDC peaks located between 196 and 262 K were attributed to polarisation caused by intrinsic dipolar defects Electronic conductivity was analysed in terms of small polaron hopping. DC conductivity depended upon iron oxide content and distance between iron ions. With increasing Fe2O3 iron ions are closer and de conductivity increases. The increase in conductivity and decrease in activation energy are related to iron cluster formation in which charge transfer takes place along a chain of such clusters.