Electrical properties of copper- and silver-containing superionic (Cu1−xAgx)7SiS5I mixed crystals with argyrodite structure

Abstract

Abstract. The copper and silver containing (Cu1−xAgx)7SiS5I mixed crystals with argyrodite structure have been grown by direct solidification using the Bridgman-Stockbarger technique. Measurements of electrical conductivity of mixed crystals by means of impedance spectroscopy were carried out in the frequency range from 2 × 101 Hz to 2 × 106 Hz and temperature range 292–378 K. Frequency dependences of total electrical conductivity were studied, Nyquist plots were constructed and analysed. The influence of Cu+ → Ag+ cation substitution on the total electrical conductivity, on the electronic and ionic components of the electrical conductivity as well as on their activation energies for (Cu1−xAgx)7SiS5I mixed crystals was investigated.