Thermoelectric properties of CoSb3 with dispersed FeSb2 particles

Abstract

We have prepared a sintered CoSb3–FeSb2 composite where the FeSb2 particles are dispersed in the CoSb3 matrix by mechanical grinding (MG) and hot pressing, and investigated the Seebeck coefficient, electrical resistivity, and thermal conductivity in order to estimate the corresponding figure of merit. The thermal conductivity of the composite is lower than that of CoSb3. The electrical resistivity of the composite increases with increasing MG time, but it is lower than that of CoSb3 at high temperature. The decrease in the thermal conductivity and the lesser increase in the electrical resistivity are ascribed to the enhancement of phonon scattering caused by the dispersion of FeSb2 particles in the CoSb3 matrix and the low electrical resistivity of FeSb2, respectively. As a result, the composite whose molar ratio of CoSb3 to FeSb2 is 0.7:0.3 and the MG time is 25 h has a maximum figure of merit value of 6.1×10−4 K−1 at 756 K. This value is much larger than the maximum value of CoSb3 at 482 K of 3.2×10−4 K−1.

Effects of doping on the high-temperature thermoelectric properties of IrSb3 skutterudite compounds

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“…[2][3][4][5][6][7][8]15 A family of compounds with the skutterudite structure (space group Im3), the general formula MX 3 , where M is the transition metal element Co, Rh, or Ir, and X is the pnicogen element, such as P, As, or Sb, has been identified as a candidate for good thermoelectric materials. The unit cell contains 8MX 3 groups.…”

A multilevel component mode synthesis approach for the calculation of the phonon density of states of nanocomposite structures

“…Many nanocomposite materials and structures have found applications in nanoelectromechanical systems (NEMS) [2], thermoelectric devices [3][4][5], engineered bio systems [6] and nanoelectronic circuits [7]. Accurate and efficient calculation of the material properties of nanocomposite materials can accelerate the design and analysis of nanocomposites in various applications as well as deepen the understanding of the material behavior.…”

Synthesis of Thermoelectric Fe<SUB>0.98</SUB>Co<SUB>0.02</SUB>Si<SUB>2</SUB> with Fine Ag Dispersion by Mechanical Milling with AgO Powder

“…Generally, in the case of such a semiconductor/metal composite, the metallic phase was mixed with thermoelectric matrix by mechanical milling. [18][19][20] However, when a ductile pure metal powder was simply added to the Fe-Si powder prior to mechanical milling, it is difficult to finely disperse metal phase in the -FeSi 2 matrix by milling only. The existence of coarse metal grains is effective for reducing electrical resistivity, but simultaneously increases its thermal conductivity.…”