Abstract Submitted for the MAR15 Meeting of The American Physical Society

o C in nanostructured p-type Nb0:6Ti0:4FeSb0:95Sn0:05composition. Even though the power factor of the Nb0:6Ti0:4FeSb0:95Sn0:05 composition is improved by 25% in comparison to the previously reported p-type Hf0:44Zr0:44Ti0:12CoSb0:8Sn0:2, the ZT value is not increased due to a higher thermal conductivity. However, the higher power factor of the Nb0:6Ti0:4FeSb0:95Sn0:05 composition led to a 15% increase in power output of a thermoelectric device in comparison to a device made from the previous best material Hf0:44Zr0:44Ti0:12CoSb0:8Sn0:2. The n-type material used to make the unicouple device is the best reported nanostructured Hf0:25Zr0:75NiSn0:99Sb0:01 composition with the lowest hafnium (Hf) content. Both the p- and n-type nanostructured samples are prepared by ball milling the arc melted ingot and hot pressing the nely ground powders. Moreover, the raw material cost of the Nb0:6Ti0:4FeSb0:95Sn0:05 composition is more than six times lower compared to the cost of the previous best p-type Hf0:44Zr0:44Ti0:12CoSb0:8Sn0:2. This cost reduction is crucial for these materials to be used in large-scale quantities for vehicle and industrial waste heat recovery applications. 1 DOE:DE-EE0004840