Preparation and Thermoelectric Properties of Bi-Doped Mg₂Si_0.8Sn_0.2 Compound

Abstract

The Bi-doped Mg₂Si_0.8Sn_0.2 single phase compound is prepared by a solid state reaction (SSR)-spark plasma sintering (SPS) method. The effect of the Bi content on the thermoelectric properties of the Bi-doped Mg₂Si_0.8Sn_0.2 compound is mainly investigated. The results show that the thermoelectric properties of the obtained samples are sensitive to the Bi content. With the increase in Bi content, the electrical conductivity (σ) and Seebeck coefficient (α) of the samples are increased, while the thermal conductivity (κ) is decreased slightly between 300 K and 850 K. When the Bi content is greater than 3.0 at%, the sample shows a maximum figure of merit (ZT) value (1.17±0.05) at 850 K.