11:30 AM - 11:50 AM
[16D-SIS11-07] Fabrication of Bi2Te3-Based Bulk Thermoelectric Materials by a Powder Extrusion Technique
Keywords:Bi2Te3, thermoelectric materials, powder extrusion
Bi2Te3-based thermoelectric materials have remained the cornerstone of commercial thermoelectric solid-state cooling and power generation near room temperature for decades. From the viewpoints of grain refinement and preferred orientation, a powder extrusion technique was proposed to fabricate Bi2Te3-based bulk materials. The p-type Bi0.4Sb1.6Te3 extruded samples achieved a maximum value of ZT=1.2, while the n-type Bi2Te2.85Se0.15 extruded samples showed a maximum value of ZT=0.47. Microstructures of the p-type and n-type extruded samples were comparably studied to demonstrate their performance bias, revealing a twining-boundary scattering mechanism. On the basis of the study, doping was employed to improve the performance of n-type extruded samples significantly.