Dc Conductivity of Ge‐S‐Ag and As‐S‐Ag Glasses

The dc conductivity in GeS 2 ‐GeS‐Ag 2 S and As 2 S 3 ‐Ag 2 S glasses was measured over the range – 20° to 80°C using an electrode of 1 at.% Ag amalgam to avoid polarization. The room‐temperature conductivity varies with increasing Ag 2 S content from 10 −15 to 10 −4 Ω −1 cm −1 for GeS 2 ‐GeS‐Ag 2 S glasses and from 10 −16 to 10 −5 Ω −1 for As 2 S 3 ‐Ag 2 S glasses. Also, the transport numbers of Ag ions in the glasses were measured by the Hittorf and emf methods. The results show that all glasses in both systems, except for compositions with low Ag 2 S contents, are purely ionic conductors because of the presence of Ag ions, so that they may be regarded as solid electrolytes.