Synthesis and thermoelectric properties of YbSb₂Te₄

The study of the ternary phase diagram Yb-Sb-Te has led to the synthesis of YbSb₂Te₄ as a pure phase by way of high energy ball milling followed by annealing, whereas typical high temperature powder metallurgy leads to multiphase sample with impurities of the very stable YbTe. The Hall mobility, Seebeck coefficient, electrical resistivity and thermal conductivity of the layered compound YbSb₂Te₄ were measured in the range of 20-550 °C. The thermoelectric figure of merit peaks at 525 K and reaches 0.5. Of particular interest is the very low lattice thermal conductivity (as low as a glass) which makes YbSb₂Te ₄ and related compounds promising thermoelectric materials.