Enhanced thermoelectric properties in Co4Sb12−xTex alloys prepared by HPHT

Fabrication and characterization of nanostructured thermoelectric FexCo1-xSb3

“…Positive sign of Seebeck coefficient reveals success of the doping-process for fabricating p-type TE materials. Although the electrical conductivity of the material is higher, the corresponding value for the Seebeck is fairly low and considering the Seebeck having higher impact on the ZT the final values of Seebeck in case of the same sample (KTH_12, 110 μV K -1 ) and references (150 μV K -1 [9] and 140 μV K -1 [12]) the ZT value obtained remains in the range of 0.18-0.25 at 800 K. The overall low Seebeck coefficient can be attributed to the presence of the FeSb 2 phase. FeSb 2 has been reported to be an n-type semiconductor [27] which considering its negative Seebeck coefficient results in a lower net value for the Seebeck of the bulk samples.…”

“…Skutterudites have an effective TE operational range from 650K to 950 K. Among the different types of skutterudites compounds, CoSb 3 based members have attracted by far the greatest interest because of constituents' abundant availability and less cost [7]. Iron substituted CoSb 3 , FexCo 1-x Sb 3 , have been reported to display good performance as a p-type TE material, in terms of its TE figure of merit (ZT), and abundance of the constituent elements [8][9][10][11][12][13][14]. The ZT can be improved via introduction of dopants, nanoengineering and in case of skutterudites, introducing rare earth elements in the crystal cages to reduce the thermal conductivity [1,[4][5][6] due to rattling of the fillers.…”

“…Most of these processes include melting the elemental powders of constituents, using high energy ball milling and finally having a high range of annealing step from 60 hours to almost 200 hours in some cases [8,9,[11][12][13][14][15][16]. Recently, Biswas et al and Ianniduo et al have adopted microwave synthesis for skutterudites production.…”

Impact of high pressure torsion on the microstructure and physical properties of Pr0.67Fe3CoSb12, Pr0.71Fe3.5Ni0.5Sb12, and Ba0.06Co4Sb12

“…Besides that, there are some state-of-art deformation methods producing nanostructured materials from bulk to bulk directly. For Ce 0.29 Fe 1.4 Co 2.6 Sb 11.24 uniaxial compression has been used under 150 MPa up to 20 cycles [14], for CoSb 3 high pressure sintering at 723 K in a pressure range from 2 to 6 GPa [15], and for Co 4 Sb 12−x Te x also high pressure sintering at 900 K under 1.5 GPa [16]. Recently, however, the new methods of severe plastic deformation have been applied, also for preparation of thermoelectric materials, for instance, equal channel angular extrusion (ECAE) [17][18][19][20][21] and high pressure torsion (HPT) [22,23] for preparation of bismuth telluride based compounds.…”

Thermoelectric properties of Ti0.2Co4Sb11.5Te0.5 prepared by HPHT

“…been studied [12]. The previous research shows that Co 4 Sb 12−x Te x compounds prepared at high pressure have higher power factor.…”