Investigation of electrical transport properties of Bi0.5Sb1.5Te2.7Se0.3 alloys prepared by high-pressure method
The quaternary Bi 0.5 Sb 1.5 Te 2.7 Se 0.3 alloys have been successfully synthesized within 25 min by high-pressure method. The pressure-dependent electrical transport properties of the as-prepared Bi 0.5 Sb 1.5 Te 2.7 Se 0.3 alloys are carefully investigated at room temperature. The measurement results indicate that the electrical resistivity and the Seebeck coefficient reveal a strong correlation with the increase of synthesis pressure. The carrier concentration and mobility are modulated effectively due to the effects of synthesis pressure and composition, leading to an improvement in the power factor of Bi 0.5 Sb 1.5 Te 2.7 Se 0.3. These results suggest that the utilization of pressure during the synthesis process provides an effective and controllable strategy to optimize the electrical transport properties of the ( Bi , Sb )2( Te , Se )3 alloys.