The high temperature performance of (Bi,Sb)2Te3 thermoelectric material was realized by collaborative optimization

Bi2te3-based alloys with strip melting have been the most widely used thermoelectric materials for decades, and their optimum operating regime is near room temperature. However, the abundance of waste heat in the medium-temperature range poses a challenge; That is how and to what extent the operating temperature of Bi2Te3 base alloy can be raised to medium temperature system. We report a collaborative optimization procedure for indium-doped and thermal deformation that combines intrinsic point defect engineering, strip structure engineering, and multi-scale microstructure. The indium-doped system regulates the internal point defects and widens the band gap, thus suppressing the harmful bipolar effect in the medium-temperature system. In addition, the thermal deformation treatment makes the multi-scale microstructure conducive to phonon scattering, and the similar donor effect helps to optimize the carrier concentration. Thus, the peak zT of ~1.4 is reached at 500K, and the average zTav of Bi0.3Sb1.625In0.075Te3 is ~1.3 between 400 and 600K. These results demonstrate the efficacy of multiple synergies and can also be used to optimize other thermoelectric materials. A popular material that converts heat into electricity can now operate at the high temperatures associated with industrial machinery. Bismuth telluride is a thermoelectric alloy that works at room temperature and can be used for refrigeration and power generation. Still, it produces much waste heat in the so-called intermediate temperature range of 100-300 degrees Celsius. Tiejun Zhu of Zhejiang University and his colleagues added indium atoms to the bismuth telluride to balance the excess, heat-activated charge carriers that generally turn into matter when the alloy is heated to an intermediate temperature. During the manufacturing process, the thermal deformation of the alloy introduces missing atom defects and microgreens, which act with doping to scatter the heat transport phonons and optimize the carrier concentration. Thermoelectric and X-ray tests show that the doped alloys have higher operating temperatures and better mechanical properties. We report a collaborative optimization procedure that combines point defect engineering, band structure engineering, and multi-scale microstructure in P-type (Bi, Sb) 2Te3 thermoelectric materials by adding indium and thermal deformation. As a result, Bi0.3Sb1.625In0.075Te3 peaked at zT~1.4 at 500K while reaching the most advanced average zTav~1.3 between 400 and 600K. These results demonstrate the efficacy of multiple synergies and can also be used to optimize other thermoelectric materials. If you are looking for high quality, high purity and cost-effective bismuth telluride, or if you require the latest price of bismuth telluride, please feel free to email contact mis-asia.