Preparation and ionic conductivity of Ag8GeS6-based ceramic materials

Herein we present the results of the study of ceramic materials made on the basis of Ag8GeS6 powders with different dispersion. The average grain size of microcrystalline powders is 10…20 µm, and that of nanocrystalline powders is ~140 and ~180 nm, respectively. The powdered materials were investigated using the XRD and SEM methods. The Ag8GeS6-based ceramic samples were obtained by annealing (1073 K) of pressed (400 MPa) discs. Investigations of the ceramics surface by using the SEM and EDS methods indicate the homogeneity of the chemical composition of the obtained ceramics. The electrical conductivity of the obtained ceramics was studied using impedance spectroscopy in a wide frequency (1·101…3·105 Hz) and temperature (293…383 K) ranges. For all these ceramics, an increase in electrical conductivity with increasing frequency is observed. Based on the obtained results, the values of ionic conductivity and activation energy of the corresponding Ag8GeS6 ceramic samples were determined.