Thermoelectric Properties of Ho-doped Bi1-xSbx

TL;DR

This study investigates how Ho-doping affects the thermoelectric properties of Bi0.88Sb0.12 alloys, revealing that small doping levels can enhance the figure of merit, ZT, at specific temperatures.

Contribution

It provides new insights into the impact of Ho-doping on the thermoelectric performance of Bi-Sb alloys, including optimal doping levels for maximum ZT.

Findings

1% Ho doping increases ZT from 0.28 to 0.31.

Doping suppresses the maximum ZT at higher doping levels.

Alloys remain single phase with nanometer grain sizes.

Abstract

The Seebeck coefficients, electrical resistivities, total thermal conductivities, and magnetization are reported for temperatures between 5 and 350 K for n-type Bi0.88Sb0.12 nano-composite alloys made by Ho-doping at the 0, 1 and 3% atomic levels. The alloys were prepared using a dc hot-pressing method, and are shown to be single phase for both Ho contents with grain sizes on the average of 900 nm. We find the parent compound has a maximum of ZT = 0.28 at 231 K, while doping 1% Ho increases the maximum ZT to 0.31 at 221 K and the 3% doped sample suppresses the maximum ZT = 0.24 at a temperature of 260 K.