Oxidation Behavior of Filled Skutterudite CeFe4Sb12 in Air

Xia, Xugui; Qiu, Pengfei; Huang, Xiangyang; Wan, Shun; Qiu, Yuting; Li, Xiaoya; Chen, Lidong

doi:10.1007/s11664-013-2820-8

Cited by 12 publications

(4 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This value of activation energy is similar to that of Fe-rich skutterudite, but is lower than that of Co-rich skutterudite, as shown in Table I. Xia et al 23 reported that a higher filling fraction for filled skutterudites contributed to low activation energy. The low activation energy observed for the La 0.9 Fe 3 CoSb 12 in this study was attributed to the unstable Fe-Sb-based skutterudite structure, with the relatively high filling fraction of y = 0.9.…”

Section: Resultssupporting

confidence: 76%

Thermal Stability of La0.9Fe3CoSb12 Skutterudite

Shin

Kim

Park

et al. 2014

Journal of Elec Materi

View full text Add to dashboard Cite

The thermal stability of the La 0.9 Fe 3 CoSb 12 skutterudite was examined by varying the aging conditions of temperature, time, and atmosphere (air and vacuum). Thermogravimetry, differential scanning calorimetry and x-ray diffraction analyses revealed that the La 0.9 Fe 3 CoSb 12 was significantly oxidized at temperatures above 673 K in air. The Sb-based oxides were preferably formed when aged at high temperatures in air. The thickness of the oxide layers was found to increase with increasing aging temperature and time, while the activation energy for the oxidation of the Fe-Sb-based skutterudite was lower than that of the Co-Sb-based skutterudites. However, when the analysis was performed in a vacuum, the La 0.9 Fe 3 CoSb 12 skutterudite was stable, and no oxide layers were observed after aging at 823 K for 100 h. These results suggest that a protective coating for the skutterudite materials or the encapsulated packaging of the skutterudite modules is required for hightemperature applications.

show abstract

Section: Resultssupporting

confidence: 76%

Thermal Stability of La0.9Fe3CoSb12 Skutterudite

Shin

Kim

Park

et al. 2014

Journal of Elec Materi

View full text Add to dashboard Cite

show abstract

“…congeners and that the activation energy for oxidation of the former is lower. [35,36] However, the impact of the rare-earth filler ions has not been examined extensively. Our data…”

Section: Stability In Air -Thermogravimetric Analysismentioning

confidence: 99%

Enhancing the thermoelectric properties of single and double filled p-type skutterudites synthesized by an up-scaled ball-milling process

Prado‐Gonjal

Vaqueiro

Nuttall

et al. 2017

Journal of Alloys and Compounds

View full text Add to dashboard Cite

The single and double filled p-type skutterudites Ce 0.8 Fe 3 CoSb 12 and Ce 0.5 Yb 0.5 Fe 3.25 Co 0.75 Sb 12 have been prepared by mechanical alloying. This offers a rapid method for the preparation of skutterudites that could be scaled up for adoption at industrial level. The large-scale samples prepared by ball-milling exhibit enhanced figures of merit ZT, compared with materials prepared by conventional solid-state reaction. At room temperature ZT is increased by ca. 19 % for both single and double filled skutterudites. Maximum figures of merit, ZT = 0.68 and ZT = 0.93 are attained for Ce 0.8 Fe 3 CoSb 12 at 773 K and Ce 0.5 Yb 0.5 Fe 3.25 Co 0.75 Sb 12 at 823 K respectively. The improvement in thermoelectric values at room temperature may be traced to a reduction in thermal conductivity in the ball-milled samples arising from the reduced grain size. The influence of the microstructure on the thermoelectric properties, together with the stability in air and the performance of the materials after several heating and cooling cycles has been studied and are detailed in this work. The densified samples prepared by ball-milling also show a higher resistance to oxidation, which starts at 694 K for Ce 0.8 Fe 3 CoSb 12 and at 783 K for Ce 0.5 Yb 0.5 Fe 3.25 Co 0.75 Sb 12 .

show abstract

“…Many materials for a variety of energy applications are susceptible to rapid oxidation under potential operating conditions. − While excellent properties of a material might be exhibited under an inert atmosphere or vacuum, in the presence of even small amounts of water, oxygen, and heat, these beneficial properties may degrade. In the example of thermoelectric materials, new materials have been prepared, showing high thermoelectric efficiencies, but in many cases, little is known about their oxidation kinetics and chemical reactions at device working temperatures. − …”

Section: Introductionmentioning

confidence: 99%

Probing High-Temperature Oxidation of Thermoelectric Phases Yb₁₄MSb₁₁ (M = Mg, Mn, Zn)

Justl

Kauzlarich

2022

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Yb14 MSb11 (M = Mg, Mn, Zn) are p-type Zintl phases with high thermoelectric efficiencies at 1000 °C and melting points above 1200 °C under vacuum and/or inert atmosphere. In a thermoelectric generator, even within a vacuum jacket, small amounts of oxygen may be present, and therefore, elucidating chemical reactions in the presence of air or oxygen provides a framework for engineering design. The oxidation of Yb14 MSb11 was investigated from room temperature to 1000 °C in dry air with thermogravimetric/differential scanning calorimetry (TG/DSC) on small pellets and visually after heat treatment to 1000 °C under ambient conditions on large pellets. Scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS) and powder X-ray diffraction provide identification of the oxidation products. In the presence of dry air, Yb14 MSb11 initially oxidizes initially slowly at room temperature with a sweeping exotherm and weight gain with rapid oxidation at 400 °C, after which the exotherm signal plateaus at about 600 °C, with M = Zn showing the smallest overall exothermic curve. All samples showed a paired endo-/exotherm at 785–803 °C, consistent with the melting/solidification of YbSb2, which in the case of M = Mg, Mn extrudes from the sample. The various sections of the pelletsouter layer, inner layer, and core are analyzed, and oxidation reactions are proposed. After cycling to 1000 °C, the outer layer is composed of Yb2O3 with small amounts of the corresponding metal oxides. The inner layer shows delamination by inward diffusion of oxygen and outward diffusion of Sb or Sb oxide-containing phases, and the core shows Yb14 MSb11. Yb14ZnSb11 shows the best resistance to oxidation and may provide a promising material for further passivation optimization.

show abstract

Oxidation Behavior of Filled Skutterudite CeFe4Sb12 in Air

Cited by 12 publications

References 20 publications

Thermal Stability of La0.9Fe3CoSb12 Skutterudite

Thermal Stability of La0.9Fe3CoSb12 Skutterudite

Enhancing the thermoelectric properties of single and double filled p-type skutterudites synthesized by an up-scaled ball-milling process

Probing High-Temperature Oxidation of Thermoelectric Phases Yb₁₄MSb₁₁ (M = Mg, Mn, Zn)

Contact Info

Product

Resources

About

Oxidation Behavior of Filled Skutterudite CeFe4Sb12 in Air

Cited by 12 publications

References 20 publications

Thermal Stability of La0.9Fe3CoSb12 Skutterudite

Thermal Stability of La0.9Fe3CoSb12 Skutterudite

Enhancing the thermoelectric properties of single and double filled p-type skutterudites synthesized by an up-scaled ball-milling process

Probing High-Temperature Oxidation of Thermoelectric Phases Yb14MSb11 (M = Mg, Mn, Zn)

Contact Info

Product

Resources

About

Probing High-Temperature Oxidation of Thermoelectric Phases Yb₁₄MSb₁₁ (M = Mg, Mn, Zn)