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 degrees 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 YbSb2Te4 and related compounds promising thermoelectric materials. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.