Thermoelectric properties of SnzCo8Sb24 skutterudites

Seebeck Coefficient in Nonparabolic Bulk Materials

“…As we shall see below, our theoretical model for determination of the Seebeck coefficient by considering the aforementioned scattering phenomena explains well the experimentally determined change of sign of S in CoSb 3 materials over a wide range of temperatures. 13 The numerical results as presented in this paper agree well with the available experimental data of S, and the theoretical results converge to the corresponding expressions of the parabolic energy band models under certain limiting conditions. The paper is organized as follows: The first subsection of ''Theoretical background'' is concerned with the formulation of the overlap integral function.…”

“…and Z = 1, to correlate with the experimental data 13 for which E g 0 and m à c 0 are defined in Table I. Figure 9 exhibits the variation of the Seebeck coefficient of Hg 1Àx Cd x Te as a function of x at room temperature and 500 K for both the screened and unscreened case using the nonparabolic energy dispersion relation.…”

“…have been identified as potential thermoelectric materials with high figure of merit. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] The common feature of all these compounds is the basic electron dispersion law defined by the second-order Kane model. 11,15,16 Although there have been extensive studies regarding both numerical and analytical formulations of different carrier transport properties considering both parabolic and nonparabolic electron energy spectra, [17][18][19][20][21][22] these often ignore the complete analytical solution of the cell overlap function which arises due to perturbation of the conduction band by the valance band when the band-gap is very narrow.…”

Synthesis and Thermoelectric Properties of In z Co4−x Fe x Sb12 Skutterudites

“…The power factor increased with increasing temperature, and more than doubled from 300 K to 700 K. The power factor was increased remarkably by Fe doping and In filling, and a maximum value of 1.2 mW/m K 2 was obtained for the In 0.25 Co 3.85 Fe 1.5 Sb 12 sample at 700 K. Figure 5 presents the temperature dependence of the thermal conductivity of In z Co 4Àx Fe x Sb 12 . Intrinsic CoSb 3 has a much higher thermal conductivity of 11 W/mK at 300 K, which decreases with increasing temperature to 7.4 W/mK at 700 K. 16 In this study, the thermal conductivity was reduced drastically by In filling and Fe doping, and was further decreased by increasing the In filling content. In 0.25 Co 4Àx Fe x Sb 12 showed very low values ($2 W/m K) at all temperatures examined.…”

Thermoelectric Properties of Ca-Filled CoSb3-Based Skutterudites Synthesized by Mechanical Alloying

“…The Seebeck coefficient of Ca 0.3 Co 3 (Fe or Mn)Sb 12 was obtained as 125 lV/K at 823 K, similar to the value of 120 lV/K at 800 K in the Ca 0.45 Co 2.4 Fe 1.6 Sb 12 reported by Tang et al 22 Figure 5 shows the temperature dependence of the thermal conductivity (j) of Ca z Co 4Àx (Fe/ Mn) x Sb 12 . The thermal conductivity was evaluated by measuring the thermal diffusivity (D), specific heat (C p ), and density (d) using the relation j = dC p D. Mallik et al 32 reported on the intrinsic CoSb 3 prepared by induction melting in an evacuated quartz ampoule. Intrinsic CoSb 3 has a much higher thermal conductivity, being 11 W/mK at 300 K and decreasing with increasing temperature to 7.4 W/mK at 700 K. In this study, however, a relatively low thermal conductivity of 2.5 W/mK to 3.9 W/mK was obtained because fine particles prepared by mechanical alloying lead to phonon scattering.…”