{"title":"Skutterudite: Reproducibility of Thermoelectric Performance of P-type RyFe4-xCoxSb12 Bulky Compacts","authors":"Jin-Sol Kim, D. Shin, K. Park, Il-Ho Kim","doi":"10.3365/kjmm.2024.62.7.542","DOIUrl":null,"url":null,"abstract":"Skutterudite compounds have excellent thermoelectric performance in the intermediate-to high temperature range. Their lattice thermal conductivity can be reduced by intensifying phonon scattering through independent vibrations of the guest atoms, by filling the voids within the lattice. Furthermore, the thermoelectric figure of merit (ZT) can be enhanced by optimizing the carrier concentration through charge compensation between transition elements. In this study, we compared the thermoelectric properties of p-type filled skutterudite materials, R<sub>y</sub>Fe<sub>4-x</sub>Co<sub>x</sub>Sb<sub>12</sub>, where R represents rare-earth elements (La/Ce/Pr/Nd/Yb), which were filled in the voids, and Co was charge-compensated at the Fe site. In the case of La<sub>y</sub>Fe<sub>4-x</sub>Co<sub>x</sub>Sb<sub>12</sub>, the introduction of La filling and Co doping led La<sub>0.9</sub>Fe<sub>3</sub>CoSb<sub>12</sub> to exhibit a high power factor and low thermal conductivity (ZT = 0.67 at 723 K). In the case of Ce<sub>y</sub>Fe<sub>4-x</sub>Co<sub>x</sub>Sb<sub>12</sub>, in addition to Ce filling, the substitution of Co for Fe resulted in additional lattice scattering, leading to a decrease in thermal conductivity. However, CeFe<sub>4</sub>Sb<sub>12</sub> exhibited a maximum performance of ZT = 0.70 at 823 K. In the case of Pr<sub>y</sub>Fe<sub>4-x</sub>Co<sub>x</sub>Sb<sub>12</sub>, the thermal conductivity was reduced through phonon scattering induced by Pr filling and additional lattice scattering caused by Co substitution; as a result, Pr<sub>0.8</sub>Fe<sub>3</sub>CoSb<sub>12</sub> exhibited ZT = 0.89 at 723 K. In the case of Nd<sub>y</sub>Fe<sub>4-x</sub>Co<sub>x</sub>Sb<sub>12</sub>, the phonon scattering was enhanced by adjusting the filling of Nd and substitution of Co, resulting in a lower thermal conductivity; Nd<sub>0.9</sub>Fe<sub>3.5</sub>Co<sub>0.5</sub>Sb<sub>12</sub> exhibited ZT = 0.91 at 723 K. For Yb<sub>y</sub>Fe<sub>4-x</sub>Co<sub>x</sub>Sb<sub>12</sub>, Yb<sub>0.9</sub>Fe<sub>3</sub>CoSb<sub>12</sub> exhibited a thermoelectric performance of ZT = 0.56 at 823 K. In addition, in this study, for the fabrication (application) of thermoelectric modules, the p-type Nd<sub>0.9</sub>Fe<sub>3.5</sub>Co<sub>0.5</sub>Sb<sub>12</sub> skutterudite, which exhibited the best thermoelectric performance, was prepared in bulky compacts to verify the uniformity and reproducibility of its thermoelectric performance.","PeriodicalId":17894,"journal":{"name":"Korean Journal of Metals and Materials","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Korean Journal of Metals and Materials","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.3365/kjmm.2024.62.7.542","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Skutterudite compounds have excellent thermoelectric performance in the intermediate-to high temperature range. Their lattice thermal conductivity can be reduced by intensifying phonon scattering through independent vibrations of the guest atoms, by filling the voids within the lattice. Furthermore, the thermoelectric figure of merit (ZT) can be enhanced by optimizing the carrier concentration through charge compensation between transition elements. In this study, we compared the thermoelectric properties of p-type filled skutterudite materials, RyFe4-xCoxSb12, where R represents rare-earth elements (La/Ce/Pr/Nd/Yb), which were filled in the voids, and Co was charge-compensated at the Fe site. In the case of LayFe4-xCoxSb12, the introduction of La filling and Co doping led La0.9Fe3CoSb12 to exhibit a high power factor and low thermal conductivity (ZT = 0.67 at 723 K). In the case of CeyFe4-xCoxSb12, in addition to Ce filling, the substitution of Co for Fe resulted in additional lattice scattering, leading to a decrease in thermal conductivity. However, CeFe4Sb12 exhibited a maximum performance of ZT = 0.70 at 823 K. In the case of PryFe4-xCoxSb12, the thermal conductivity was reduced through phonon scattering induced by Pr filling and additional lattice scattering caused by Co substitution; as a result, Pr0.8Fe3CoSb12 exhibited ZT = 0.89 at 723 K. In the case of NdyFe4-xCoxSb12, the phonon scattering was enhanced by adjusting the filling of Nd and substitution of Co, resulting in a lower thermal conductivity; Nd0.9Fe3.5Co0.5Sb12 exhibited ZT = 0.91 at 723 K. For YbyFe4-xCoxSb12, Yb0.9Fe3CoSb12 exhibited a thermoelectric performance of ZT = 0.56 at 823 K. In addition, in this study, for the fabrication (application) of thermoelectric modules, the p-type Nd0.9Fe3.5Co0.5Sb12 skutterudite, which exhibited the best thermoelectric performance, was prepared in bulky compacts to verify the uniformity and reproducibility of its thermoelectric performance.
沸石化合物在中高温范围内具有出色的热电性能。通过填充晶格内的空隙,利用客体原子的独立振动加强声子散射,可以降低晶格热导率。此外,还可以通过过渡元素之间的电荷补偿优化载流子浓度,从而提高热电功勋值(ZT)。在本研究中,我们比较了 p 型填充矽卡岩材料 RyFe4-xCoxSb12 的热电性能,其中 R 代表稀土元素(La/Ce/Pr/Nd/Yb),填充在空隙中,Co 在 Fe 位点进行电荷补偿。就 LayFe4-xCoxSb12 而言,由于引入了 La 填充和 Co 掺杂,La0.9Fe3CoSb12 表现出较高的功率因数和较低的热导率(723 K 时 ZT = 0.67)。就 CeyFe4-xCoxSb12 而言,除了 Ce 填充外,用 Co 代替 Fe 还导致了额外的晶格散射,从而降低了热导率。然而,CeFe4Sb12 在 823 K 时表现出 ZT = 0.70 的最大性能。在 PryFe4-xCoxSb12 的情况中,Pr 填充引起的声子散射和 Co 取代引起的额外晶格散射导致热导率降低;因此,Pr0.8Fe3CoSb12 在 723 K 时的 ZT = 0.89。在 NdyFe4-xCoxSb12 的情况下,通过调整 Nd 的填充和 Co 的替代,声子散射增强,导致热导率降低;Nd0.对于 YbyFe4-xCoxSb12,Yb0.9Fe3CoSb12 在 823 K 时的热电性能为 ZT = 0.56。9Fe3.5Co0.5Sb12沸石的热电性能最好,为了验证其热电性能的均匀性和可重复性,我们将其制备成体积较大的压块。
期刊介绍:
The Korean Journal of Metals and Materials is a representative Korean-language journal of the Korean Institute of Metals and Materials (KIM); it publishes domestic and foreign academic papers related to metals and materials, in abroad range of fields from metals and materials to nano-materials, biomaterials, functional materials, energy materials, and new materials, and its official ISO designation is Korean J. Met. Mater.