Synthesis and thermoelectric properties of bismuth-antimony-tellurium-based nanopowders

摘要

Bismuth-antimony-tellurium-based nanopowders were fabricated by a chemical process in which dissolved Bi, Te and Sb salts were directly reduced in each element via surfactant-assistant polyol reducing agents. XRD patterns of the synthesized nanopowders showed that the formed phases correspond mainly to (Bi_(0.5)Sb_(0.5))2Te3 and Bi_(0.5)Sb_(1.5)Te3, respectively. The phases revealed that the three different elements were stably alloyed as ternary composition in one powder via the simple chemical route. The nanopowders were consolidated into bismuth telluride-based bulk materials that exhibited electrical resistivity above 5.6 x 10~(-5) 0m, 150 μ V/K of the Seebeck coefficient and 0.7 W/mK of thermal conductivity at room temperature. These results showed that p-type thermoelectric nanopowders obtained from a simplified chemical process could be used in making thermoelectric materials towards high performances.