Composition dependence of electric conductivity in silver vanadate superionic glasses

Electrical properties of silver vanadate superionic glasses of compositions : 50AgI . (50-x)Ag2O . xV(2)O(5), 14 less than or equal to x less than or e qual to 25 and yAgI . (80-y)Ag2O . 20V(2)O(5), 30 less than or equal to y l ess than or equal to 50 have been investigated by impedance spectroscopy me thod. Ionic conductivity of the latter glasses exponentially increases on i ncrease of AgI content. The earlier reports on the formation of a highly co nductive substructure at AgI content higher than 40 mol% seem to be confirm ed. Isotherms of conductivity versus glass-network content (x) and glass-mo difier content (50-x or 80-y) indicate that the maximum value of ionic cond uctivity corresponds to a composition characterized by the parameter r = [A g2O]/[V2O5] approximate to 1.4 The glass network of such glasses consists o f pyrovanadate groups V2O7 and metavanadate chains.