Fabrication of Ag-Sn-Sb-Te based thermoelectric materials by MA-PAS and their properties

Starting from elemental powder mixtures of AgSn18SbTe20 and Sn50Te50, P-type AgSn18SbTe20 and Sn50Te50 bulk thermoelectric materials were fabricated by a combined process of mechanical alloying (MA) and plasma activated sintering (PAS). It was found that SnTe compound could be easily synthesized after milling only for 1 h. Prolonging the milling time, Ag and Sb atoms diffused into the lattice of the primary SnTe compound gradually and SnTe-based solid solution was formed. The electrical resistivity and Seebeck coefficient of the as-PASed samples were measured from 323 K to 723 K. The maximum power factor of 1.98 x 10(-3) Wm(-1) K-2 was obtained at 673 K for AgSn18SbTe20 and it was higher than that of the material with similar composition from previous published literature. (C) 2010 Elsevier B.V. All rights reserved.