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 equal to 25 and yAgI . (80-y)Ag2O . 20V(2)O(5), 30 less than or equal to y less than or equal to 50 have been investigated by impedance spectroscopy method. Ionic conductivity of the latter glasses exponentially increases on increase of AgI content. The earlier reports on the formation of a highly conductive substructure at AgI content higher than 40 mol% seem to be confirmed. Isotherms of conductivity versus glass-network content (x) and glass-modifier content (50-x or 80-y) indicate that the maximum value of ionic conductivity corresponds to a composition characterized by the parameter r = [Ag2O]/[V2O5] approximate to 1.4 The glass network of such glasses consists of pyrovanadate groups V2O7 and metavanadate chains.