Sections Pb6Sb2Bi6Se18–Sb2Se3 and Pb6Sb2Bi6Se18–Bi2Se3 of the Quasi-Ternary System Sb2Se3–PbSe–Bi2Se3

Abstract

Phase equilibria in the sections Pb₆Sb₂Bi₆Se₁₈-Sb₂Se₃ and Pb₆Sb₂Bi₆Se₁₈-Bi₂Se₃ were studied by differential thermal, X-ray powder diffraction, and microstructural analyses and by microhardness and density measurements, and the state diagrams of these sections were constructed. It was determined that these sections are eutectic-type quasi-binary sections of the Sb₂Se₃-PbSe-Bi₂Se₃ system. The coordinates of the eutectic point in the section Pb₆Sb₂Bi₆Se₁₈-Sb₂Se₃ are 40 mol% Pb₆Sb₂Bi₆Se₁₈ and 700 K, and those in the section Pb₆Sb₂Bi₆Se₁₈-Bi₂Se₃ are 60 mol% Bi₂Se₃ and 725 K. At room temperature, regions of solid solutions based on the initial components in the sections were identified. Procedures were developed for growing single crystals of solid solutions based on both components by the Bridgman-Stockbarger method and chemical transport reactions. The properties of alloys of solid solutions based on Pb₆Sb₂Bi₆Se₁₈ and Bi₂Se₃ were investigated. These alloys were found to be p-type semiconductors.