Phase Equilibria in the YbTe-PbTe-Bi2Te3 System

The phase equilibria in the YbTe-PbTe-Bi2Te3 system were investigated by means of differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscope with energy dispersive analysis (SEM-EDS) techniques. Isothermal sections at 300 and 800 K, the liquidus surface projection as well as some isopleth sections were experimentally plotted. The already reported ternary YbPbTe2, YbBi2Te4 and YbBi4Te7 compounds were not confirmed. Wide solid solubility field of initial binary compounds was revealed and a solubility of YbTe in the ternary tetradymite-like layered compounds in the PbTe-Bi2Te3 system are found to be about 2 mol%.