THERMODYNAMIC PROPERTIES OF Pb6Sb6Se17

Abstract

The Pb–Sb–Se system was investigated in the PbSe–Pb6Sb6Se17–Sb2Se3–Se composition area and temperature range 300–450 K using EMF measurements on reversible concentration cells of the type (–)PbSe(s) | liquid electrolyte, Pb2+ | (Pb–Sb–Se)(s)(+). It was shown that this subsystem consists of two three-phase regions, limited by the Pb6Sb6Se17-Sе tie-line. Partial thermodynamic functions of PbSe and lead in tree-phase Pb6Sb6Se17–Sb2Se3–Se region are calculated from the equations for the EMF temperature dependences. The standard Gibbs energy of formation, standard enthalpy of formation and standard entropy of the Pb6Sb6Se17 compound were calculated based these data and using the thermodynamic functions for PbSe and Sb2Se3.

Keywords

• lead-antimony selenides
• Pb6Sb6Se17
• EMF method
• thermodynamic properties.