산화물 환원법으로 제조된 BixSb2-xTe3 분말의 열전특성

Abstract

This study investigated the change of thermal and electrical properties of BixSb2-xTe3 (x=0.00, 0.14, 0.40, 0.64) prepared by an oxide reduction process and then sintered by spark plasma sintering. Thermoelectric materials that are composed of p-type antimony telluride, which are suitable for low-temperature power generation and cooling, were successfully obtained through Bi-alloying, which suppresses extrinsic conduction at elevated temperatures by decreasing hole concentrations and material band gaps. Furthermore, Bi-alloying in antimony telluride reduced the thermal conductivity at 298K and 323K. Bi contents in BixSb2-xTe3 sintered body indirectly analysed by vegard’s law through XRD result data. Electrical properties of BixSb2-xTe3 sintered body was appraised at Seebeck coefficient and Electrical resistivity using a ZEM-3 equipment. Seebeck coefficient and Electrical resistivity increased at the room temperature by decreasing the carrier concentration with increasing Bi contents. Thermal conductivity of BixSb2-xTe3 sintered body decreased at 298K and 323K reducing the electrical thermal conductivity, lattice thermal conductivity with increasing Bi contents. The maximum figure of merit(ZT) obtained was 1.21 at 323K for the Bi0.4Sb1.6Te3 sample.