High Temperature Transport Properties of Yb and In Double-Filled p-Type Skutterudites

Abstract

Yb and In double-filled and Fe substituted polycrystalline p-type skutterudite antimonides were synthesized by direct reaction of high-purity elements, followed by solid-state annealing and densification by hot pressing. The stoichiometry and filling fraction were determined by both Rietveld refinement of the X-ray diffraction data and energy dispersive spectroscopic analyses. The transport properties were measured between 300 K and 830 K, and basically indicate that the resistivity and Seebeck coefficient both increase with increasing temperature. In both specimens, the thermal conductivity decreased with increasing temperature up to approximately 700 K, where the onset of bipolar conduction was observed. A maximum ZT value of 0.6 at 760 K was obtained for the Yb 0.39 In 0.018 Co 2.4 Fe 1.6 Sb 12 specimen.

Effect of partial Yb filling on thermoelectric properties of skutterudite compound RhSb3

“…Many studies of CoSb 3 -based skutterudite compounds have been conducted on reducing the lattice thermal conductivity κ l by partially various guest ions filling in the voids to improve TE performance. [6][7][8][9][10][11][12][13][14] Among various kinds of filling ions such as alkaline-earth and rare earth ones, Yb ion has heavy mass and small radius compared to other filling ones. Therefore, partially Yb-filled CoSb 3 has represented high TE performance.…”

Thermoelectric properties of partially filled skutterudites Rx Co4Sb12 (R = Ce and Nd) synthesized under high pressures

“…1,[10][11][12][13] Furthermore, double filling with guest ions such as (Ce and Yb), (In and Yb), (In and Ba), and (Ba and Yb) and multifilling such as (Ba, La, and Yb) and (Ce, In, and Yb) are also effective for improving the TE properties. 3,11,[14][15][16][17][18] This is due to the additional effects of disorder and mass fluctuation scattering of guest ions occurring between guest ions inside the voids and lattice. 19) The reduction in κ l for a partially filled skutterudite is one promising method for improving the TE performance.…”