| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Alloys and Compounds for Thermoelectric and Solar Cell Applications VIII
|
| Presentation Title |
Portable Nanostructured Magneto-Thermoelectric Bi-Sb Alloys at Cryogenic Temperatures |
| Author(s) |
Joseph S. Poon |
| On-Site Speaker (Planned) |
Joseph S. Poon |
| Abstract Scope |
Thermoelectrics play a vital role in heat-to-electrical energy conversion and refrigeration. Bismuth antimony is a promising material for thermoelectric cooling. A high figure of merit ZT~ 0.6 at 100K was measured in nanocrystalline n-type Bi-Sb, 50% higher than the polycrystalline ZT 0.4. Magneto-thermoelectric effects further improved the TE properties, increasing ZT to 0.7 in a portable compact BiSb/NdFeB system. The improved thermoelectric properties can be attributed to the nanostructure achieved from rapid solidification, which not only significantly reduced the thermal conductivity but also avoided phase segregation. The thermoelectric properties were analyzed within a two-band model to provide a deeper understanding of the transport mechanisms. The study revealed a heretofore unknown narrowing of the band gap at increasing temperature. The easily accessible low magnetic field for high ZT enables the utilization of BiSb in thermoelectric cooling.
In collaboration with Sheng Gao, Dr. John Gaskins, Xixiao Hu, and Prof. Patrick Hopkins. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |