Fabrication parameters for optimized thermoelectric Mg2Si

Here, we report on the effect of sintering temperature, particle size, and sintering pressure on the thermoelectric properties of Sb-doped Mg2Si samples. We find a strong dependence of thermoelectric performance on sintering temperature with the best properties achieved at 900 °C. We furthermore show a strong influence of the particle size of the employed powder, with coarser powder giving better properties. The difference stems mainly from the electrical conductivity; Seebeck coefficient and thermal conductivity are affected to a lesser extent. With respect to sintering pressure, a small positive influence of increasing pressure is found. We obtain a peak thermoelectric figure of merit of 0.75 ± 0.18 at 820 K employing optimized fabrication parameters.