Neutron diffraction and thermoelectric properties of indium filled In_xCo₄Sb₁₂ (x = 0.05, 0.2) and indium cerium filled Ce_0.05In_0.1Co₄Sb₁₂ skutterudites

Abstract

The thermoelectric properties on polycrystalline single (In) and double filled (Ce, In) skutterudites are characterized between 300 and 700 K. Powder neutron diffraction measurements of the skutterudite compositions InxCo4Sb12 (x = 0.05, 0.2) and Ce0.05In0.1Co4Sb12 as a function of temperature (12–300 K) were carried out, which gives more insight into the structural data of single and double‐filled skutterudites. Results show that due to the annealing treatment, a Sb deficiency is detectable and thus verifies defects at the Sb lattice site of the skutterudite. Furthermore, we show by electron microprobe analysis that a considerable amount of indium is lost during synthesis and post‐processing for the single indium filled samples, but not for the double cerium and indium skutterudite sample. In our experiments, the double‐filled skutterudite is superior to the single‐filled skutterudite composition due to a higher charge carrier density, a comparable lattice thermal resistivity, and a higher density of states effective mass. Furthermore, we obtained a significantly higher Einstein temperature for the double‐filled skutterudite composition in comparison to the single‐filled species, which reflects the high sensitivity due to filling of the void lattice position within the skutterudite crystal.

Enhanced Thermoelectric Performance of Yb-Single-Filled Skutterudite by Ultralow Thermal Conductivity

“…The isotropic atomic displacement parameters (ADPs) of the Yb filler were found to be about one order of magnitude larger than those of the Co/Fe and Sb matrix atoms, which is consistent with the results reported in other single-filled skutterudites . Interestingly, the ADPs of Co/Fe were also found to be generally larger than that of Co in a single-filled CoSb 3 matrix, probably leading to lower thermal conductivity with higher disordering.…”

Reaction mechanism and thermoelectric properties of In0·22Co4Sb12 prepared by magnesiothermy

“…Unfortunately, the grain growth induced during sintering cancels this microstructural feature and both thermal conductivity and figure-of-merit are much closer from those obtained by fusionsolidification-long term annealing[2,18] or most recently by scanning laser melting for higher In-content[41]. Nevertheless, our ZT value is most of the time higher than those reported after solid state diffusion[39,42,43] or HPHT technique[44]. Improving the SPS step to limit the grain growth, stabilizing In 0.22 Co 4 Sb 12 /InSb nanocomposites or trying to form multifilled skutterudites by magnesiothermy are the perspectives of this work.…”

Candidate for Magnetic Doping Agent and High-Temperature Thermoelectric Performance Enhancer: Hard Magnetic M-type BaFe12O19 Nanometer Suspension

“…The largest ZT was about 1.2 at 675 K for the BaM45 nanocomposite. The average ZT ( ZT avg ) value of BaM45 was close to 1.2 in the range of 650–800 K. This ZT avg is obviously better than that reported in some other literature on In-filled CoSb 3 materials, − as shown in Figure . These results showed that BaFe 12 O 19 NPs in the nanocomposites were helpful in maintaining high ZT values above the IE temperature.…”