Paper EN-ThP8
Thermoelectric Properties of SbI₃ Doped Bi₂Te₃+Bi₂Se₃ Alloys by Mechanical Alloying and Spark Plasma Sintering

Thursday, November 1, 2012, 6:00 pm, Room Central Hall

Thermoelectric (TE) materials and its devices provide attractive increasing attention because of their potential applications in the field of energy conversion, cooling for electronic devices and thermal sensors. For enhancing the thermoelectric performance, we fabricated the microsized n-type Bi2Te3+Bi2Se3 (Bismuth- Tellurium-Selenium) with different compositions doped with 0.05 wt%SbI3 alloys via high energy mechanical alloying which is associated with vacuum atmosphere. The milled powder was consolidated by Spark Plasma Sintering (SPS) technique at the temperature range of 400^oC with a holding time of 10 minutes at 50 MPa pressure. The effects of milling time and temperatures were investigated. In order to investigate microstructural analysis of the samples, both Optical microscope (OM) and Scanning Electron Microscope (SEM) were used. The phase of different compounds was characterized by X-ray Diffraction (XRD). Mechanical properties were calculated by measuring the density and micro Vickers hardness of the samples. The temperature dependence of the Seebeck coefficient, electrical resistivity and hall coefficient were determined for the alloys samples with different compositions. From the experimental results, the thermoelectric properties are mainly influenced by the milling time, vacuum condition and temperature. The maximum values of Figure-of-merit (ZT) for the different compounds of samples were calculated using the thermoelectric properties.