Materials Chemistry and Physics, Vol.177, 353-359, 2016
Thermoelectric properties of bismuth-antimony-telluride alloys obtained by reduction of oxide reagents
The Bi-Sb-Te alloys with different Bi/Sb/Te ratio were fabricated by an innovative method. For that purpose the oxide reagents were melted at high temperature, then quenched to form pellets, milled to a powder and finally reduced in hydrogen at various temperatures. Complex structures consisting of connected thin layers forming a continuous path between nano- and micrometer size grains have been obtained. The electrical conductivity, Seebeck coefficient and thermal conductivity have been determined over temperature range from -196 to +300 degrees C in argon atmosphere. The highest figure of merit in the whole temperature range was found for Bi-0.4Sb1.6Te3 compound reduced at 400 degrees C for 10 h in hydrogen atmosphere. At a near-room temperature the figure of merit of this compound was found to be equal to 0.7. (C) 2016 Elsevier B.V. All rights reserved.