Thermoelectric Properties of Mn-Doped β-FeSi₂ Fabricated by Spark Plasma Sintering

Abstract

The thermoelectric properties of dense Fe_1-xMn_xSi₂ (0.00≤x≤0.10) fabricated by spark plasma sintering have been characterized in the temperature range between 300 and 1150K. Fe_1-xMn_xSi₂ is p-type over the measured temperature range. The electrical resistivity (ρ), Seebeck coefficient (S) are strongly affected by the Mn doping concentration (x). The thermal conductivity, (κ) of Fe_1-xMn_xSi₂ is mainly ascribed to the lattice component (κ_ph). At low temperatures, the κ of Fe_1-xMn_xSi₂ is much higher than that of Fe_1-xCo_xSi₂. At x=0.10, the power factor (P=S²/ρ) and the dimensionless figure of merit (ZT) show maximum values of 9.3×10^-4W/m·K² at 940K and 0.21 at 1040K, respectively.