Effect of Anisotropy on the Thermoelectric Properties of Bi_1Sb_3Te_6 Added with Au Alloys Prepared by Mechanical Alloying Process

摘要

An effect of anisotropy on the thermoelectric properties of Bi_1Sb_3Te_6 added with Au alloys prepared by a mechanical alloying process has been studied. The conduction properties including electrical conductivity and thermal conductivity were increased with Au content. The electrical conductivity and the power factor of the perpendicular direction to the pressing direction were larger than those of the parallel direction to the pressing direction. The intensity of (110) perpendicular plane was larger than that of the parallel plane. It was suggested that the increase of intensity of the (110) plane would contribute to improve the thermoelectric performance. Although the power factor and thermal conductivity revealed the anisotropic behavior with direction, the Z value showed almost the equal value regardless of direction. From these results, it appeared that the Z value of the Bi_1Sb_3Te_6 added with Au alloy prepared by powder metallurgy process was almost isotropic.