Enhanced thermoelectric figure of merit of p-type Si0.8Ge0.2 nanostructured spark plasma sintered alloys with embedded SiO2 nanoinclusions

Abstract We report on thermoelectric properties of p -type boron doped nanostructured bulk Si 80 Ge 20 synthesized via spark plasma technique. We demonstrate that the presence of a limited amount of nanometer-sized SiO 2 inclusions, resulting from the oxidation during processing stages is an effective way to further thermal conductivity reduction in the nanostructured Si 80 Ge 20 alloys. Significant reduction of thermal conductivity and high values of Seebeck coefficient allowed us to reach a peak ZT value of about 0.72 at 800 °C in boron doped Si 80 Ge 20 .