Ambient temperature thermoelectric performance of thermally evaporated p-type Bi-Sb-Te thin films

摘要

Bismuth antimony telluride (BST) compounds have shown a promising performance in low to medium temperature thermoelectric (TE) conversion. One such composition, Bi_(1.2)Sb_(0.8)Te_3, was synthesized by melting elemental entities and thin films of the as-synthesized material were deposited by thermal evaporation. X-Ray Diffraction analysis was conducted to study the crystallographic phases and other structural properties. Electrical conductivity and Seebeck coefficient measurements of as-prepared thin films were conducted in the temperature range from 303-363 K with a view to study ambient temperature application of the synthesized material for power generation in which an increasing trend was observed in the Seebeck coefficient. Electrical conductivity displayed a maximum value of 0.22 × 10~4 Sm~(-1) that was comparable to other Bi-Sb-Te compositions whereas power factor had its peak at 323 K. These trends observed in electrical properties indicate that synthesized material can be used for room temperature TE module fabrication.