The electrical conductivity of fluorozirconate and chloro-fluorozirconate glasses

The electrical conductivities of glasses in the ZrF₄-BaF₂ and ZrF₄-BaF₂-BaCl₂ systems have been measured as a function of temperature. The conductivies of binary fluorozirconate glasses had values comparable to those previously measured for ternary systems. The introduction of chlorine in the glass network markedly decreased the electrical conductivity and increased the activation energy for conduction. The decrease in conductivity could not be explained exclusively on the basis of zero mobility for the Cl atoms; it is proposed that these atoms effectively hinder the motion of the conducting fluorine ions. The activation energy for electrical conduction in fluorozirconate glasses was analysed via a modification of the Anderson and Stuart model for anionically conducting glasses, in which the electrostatic energy was found to predominate. In chlorofluorozirconate glasses, this term appears to be less predominant.