Thermal and Thermoelectric Properties of Bi-Te-Sb and Bi-Te-Se Doped by Carbon Additive

In this work, the thermoelectric and thermal properties of materials based on Bi-Te-Sb and Bi-Te-Se with various concentrations of carbon additive were studied. The mass percentage of alloying additives was from 0.1% to 2.0%. The electrical conductivity, Seebeck coefficient, power factor and thermal properties were measured. The highest values of electrical conductivity were possessed by legs of thermoelements with an additive concentration of 0.1% and 0.5% (for n- and p-type respectively). However, for the Seebeck coefficient, the maximum values were observed for a concentration of 1%, which also determines the maximum values of the power factor, so this composition is the most optimal. Thermal stability studies have shown that there is no phase transformations the investigated materials in the required temperature range (from 20 °C to 150 °C). Thus, it was shown that C45 is a promising additive for optimizing the properties of thermoelectric materials.