Enhanced Thermoelectric and Mechanical Performances in Sintered BiSbTe-AgSbSe Composite.

Bismuth telluride alloys have dominated the industrial application of thermoelectric cooling, but the relatively poor mechanical performance of commercial zone-melting material seriously limits the device integration and stability. Here, we exhibit synergistically enhanced thermoelectric and mechanical performances of sintered BiSbTe-AgSbSe composites. It is found that the increased hole concentration improves the σ to 40 μW cm K at room temperature, and the emerged various defects effectively suppress the to 0.57 W m K at 350 K. All effects harvest a highest = 1.2 at 350 K along with an average = 1.0 between 300-500 K in the = 0.2 sample. Notably, AgSbSe addition not only optimizes the thermoelectric properties, but also enhances the mechanical performance with a Vickers hardness of 0.75 GPa. Furthermore, the isotropy of thermoelectric properties is also observably promoted by solid-phase reaction combined with high-energy ball milling and hot pressing. Our study reveals a viable strategy to improve the comprehensive performance of sintered bismuth telluride materials.