Synthesis and Thermodynamic Investigation of Energy Materials in the Ag–Te–Cl System by the Solid-State Galvanic Cells

Discoveries of new energy materials with unique properties and wider thermal stability ranges enable sustainable developments toward a low-carbon society. In this work, phase stabilities and thermodynamic properties of selected compounds in the Ag-Te-Cl system with potential application as energy materials have been critically reviewed and experimentally investigated. Based on the literature data on phase formations in the AgCl-Ag2Te-Te part of the Ag-Te-Cl system and the results of electromotive force (EMF) measurements in this work, formations of the Ag19Te6Cl7, Ag10Te4Cl3, Ag5Te2Cl, and Ag23Te12Cl compounds below 500 K were established. The EMF measurements were performed in carefully built galvanic cells with positive electrodes prepared from finely ground mixtures of pure substances Ag, Te, and AgCl. Based on the temperature dependences of the EMF of the cells, the standard thermodynamic quantities of the ternary compounds of the Ag-Te-Cl system were experimentally determined for the first time.