Thermal Analysis and Optimization of the Phase Diagram of the Cu-Ag Sulfide System

Fiseha Tesfaye*, Daniel Lindberg, Dmitry Sukhomlinov, Pekka Taskinen, Leena Hupa

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

1 Citation (Scopus)
41 Downloads (Pure)


Thermal stabilities of selected ternary phases of industrial interest in the Ag-Cu-S system have been studied by the calorimetric and electromotive force techniques. The ternary compounds Ag1.2Cu0.8S (mineral mackinstryite) and AgCuS (mineral stromeyerite) were equilibrated through high-temperature reaction of the pure Cu2S and Ag2S in an inert atmosphere. The synthesized single solid sample constituting the two ternary phases was ground into fine powders and lightly pressed into pellets before calorimetric measurements. An electrochemical cell incorporating the two equilibrated phase and additional CuS as a cathode material was employed. The measurement results obtained with both techniques were analyzed and thermodynamic properties in the system have been determined and compared with the available literature values. Enthalpy of fusion data of the Ag-richer solid solution (Ag,Cu)2S have also been determined directly from the experimental data for the first time. The thermodynamic quantities determined in this work can be used to calculate thermal energy of processes involving the Ag-Cu-S-ternary phases. By applying the obtained results and the critically evaluated literature data, we have developed a thermodynamic database. The self-developed database was combined with the latest pure substances database of the FactSage software package to model the phase diagram of the Ag2S-Cu2S system.
Original languageEnglish
Article number593
Pages (from-to)1-15
Number of pages15
Issue number2
Publication statusPublished - 14 Jan 2022
MoE publication typeA1 Journal article-refereed


  • Sulfides
  • Copper
  • Silver
  • Inorganic materials
  • Thermal analysis
  • Thermochemistry
  • Thermal energy
  • Phase diagram


Dive into the research topics of 'Thermal Analysis and Optimization of the Phase Diagram of the Cu-Ag Sulfide System'. Together they form a unique fingerprint.

Cite this