Preparation and thermoelectric properties of Mg₂Si_1−<i>x</i>Sn_<i>x</i>

Abstract

Mg2Si1−xSnx (x = 0.2, 0.4, 0.6 and 0.8) thermoelectric materials have been prepared by vacuum melting and melting/hot-pressing methods. The phase structures and electrical transport properties were measured. The relationships between electronic structures and electronic properties are discussed. X-ray diffraction (XRD) showed that the hot-pressed compounds were better formed. The electrical conductivity and Seebeck coefficient measurements showed that the properties of the compounds were dramatically affected by solid solubility. When x= 0.2, the highest electrical conductivity resulted in the highest power factor of 1.32×10−3 W m−1 K−2 at about 500 K, while the highest value of Seebeck coefficient of −459 μV K−1 was obtained at about 450 K for x= 0.6.