Investigation of Thermoelectric Properties with Dispersion of Fe2O3 and Fe-85Ni Nanospheres in Bi0.5Sb1.5Te3 Matrix

다국어 초록 (Multilingual Abstract)

<P>In this work, we fabricated Bi0.5Sb1.5Te3 thermoelectric alloys using the mass-production technique, and subsequently Fe2O3 and Fe-85Ni alloy nanoparticles were dispersed in the matrix by high energy ball milling and consolidated using spark plasma sintering technique. The influence of Fe2O3 and Fe-85Ni alloy spherical nanoparticles in Bi0.5Sb1.5Te3 (BST) matrix on thermoelectric transport properties has been investigated. The x-ray diffraction and scanning electron microscopy results show that the nanoparticles were dispersed in the matrix. The spark plasma sintered bulk BST/Fe2O3 composite sample exhibited high Seebeck coefficient which was 39% higher than the bare BST due to low carrier concentration and a significant reduction in the thermal conductivity (38%) owing to enhanced carrier scattering by the dispersed nanoparticles compared to that of the bare BST sample. As a result, the maximum ZT values for the BST, BST/Fe2O3, and BST/Fe-85Ni samples were found as 1.17, 0.98, and 0.88 at 375 K, respectively. Micro Vickers hardness of BST/Fe2O3 and BST/Fe-85Ni composite samples was significantly enhanced compared to bare Bi0.5Sb1.5Te3 sample.</P>