Thermoelectric properties of Ni-doped BaSi2

Abstract

BaSi2 has been known as a wide gap semiconductor with an intrinsic low lattice thermal conductivity, therefore may be a promising environmental friendly thermoelectric (TE) material with abundant constituent elements. In this work, NixBa[Formula: see text]Si2 compounds with 0[Formula: see text] are synthesized by arc melting. The resistivity, thermal conductivity and Seebeck coefficient are measured in the temperature range of 300–850[Formula: see text]K. The resistivity of the undoped BaSi2 is as high as 480[Formula: see text]mOhm[Formula: see text]cm at room temperature. Through Ni-doping, both resistivity and the Seebeck coefficient decrease dramatically. Meanwhile, the total thermal conductivity has no apparent difference due to Ni-doping. The lattice thermal conductivity decreases with increasing temperature monotonously to be lower than 1[Formula: see text]W/m[Formula: see text]K at high temperatures.