Thermoelectric Performance of Bi1.8Sb0.2Te3.0 Alloys under High Pressures

Abstract


 The pressure effect on the thermopower has been investigated for the Bi1.8Sb0.2Te3.0 alloys. We have found an anisotropic pressure dependence on the thermopower for p- and n-type Bi1.8Sb0.2Te3.0 at room temperature. Along a-axis, for p-type, the thermopower value increased with increase of pressure at a rate of 13.9 %/Gpa, whereas, along c-axis, itkeeps approximately constant.. The absolue value of the thermopower decreased with pressure along both a- and c-axis for n-type. The power factor increased largely with increase of pressure for p-type Bi1.8Sb0.2Te3.0, while it is approximately constant for n-type.