Ionic Conductivity at Room Temperature and Thermal Stability of Chlorine-Conducting Solid Electrolytes

Search for chlorine-conducting solid electrolytes with a high ionic conductivity σ 293K at room temperature (293 K) is based on the analysis of temperature measurements of the electrical conductivity σ( T ) of simple and complex compounds, solid solutions, composites, and glasses. A comparison of the thermal stability of chlorides is based on the analysis of the dependences σ( T ) in cyclic heating–cooling measurements and the physicochemical data. Maximum σ 293K values were found for the solid solutions (3 × 10 −5 S/cm) and (1 × 10 −4 S/cm). Promising directions of search for chlorine-ion solid electrolytes for chemical current sources and chlorine sensors operating at room temperature are the method of crystallochemical heterovalent substitutions and implementation of the vacancy mechanism of electrical conductivity in crystal structures of the cotunnite (PbCl 2 ) and fluorite (CaF 2 ) types. The parameters of the ionic conductivity of cotunnite and fluorite crystals of chlorides and fluorides are analyzed.