Synthesis of Bi_(0.5)Sb_(1.5)Te_3 Thermoelectric Powder Using an Oxide-Reduction Process

摘要

The present study focused on synthesis of Bi_(0.5)Sb_(1.5)Te_3 thermoelectric powder using an oxide-reduction process. The phase structure and particle size of the synthesized powders were analyzed using x-ray diffractometry and scanning electron microscopy. The synthesized powder was sintered using the spark plasma sintering method. The thermoelectric properties of the sintered body were evaluated by measuring the Seebeck coefficient, electrical resistivity, and thermal conductivity. Bi_(0.5)Sb_(1.5)Te_3 powder was synthesized using a combination of mechanical milling, calcination, and reduction processes, using a mixture of Bi_2O_3, Sb_2O_3, and TeO_2 powders. The sintered body of the oxide-reduction-synthesized Bi_(0.5)Sb_(1.5)Te_3 powder showed p-type thermoelectric characteristics. The thermoelectric properties of the sintered bodies depended on the reduction time. After being reduced for 2 h at 663 K, the sintered body of the Bi_(0.5)Sb_(1.5)Te_3 powder showed a figure of merit of approximately 1.0 at room temperature.