Preparation and Thermoelectric Properties of Zinc Antimonide

We have demonstrated two processes for the synthesis of zinc antimonide powder using rapid melt cooling: melt spinning and cooling in a liquid. The elemental and phase compositions and surface morphology of hot-pressed undoped and 3 wt % In-doped beta-Zn4Sb3 samples have been studied by scanning electron microscopy, X-ray diffraction, and optical microscopy, and their Seebeck coefficient, electrical conductivity, and thermal conductivity have been measured in the range 300-700 K. Indium doping has been shown to reduce the lattice thermal conductivity of the material by a factor of 1.5. The 600-K thermoelectric figure of merit of the undoped sample (ZT = 0.8) is half that of the doped sample (ZT = 1.5). We have assessed the effect of thermal cycling in the range 300-700 K on the Seebeck coefficient and electrical conductivity of the samples.