Does Low‐Level Substitution Aid in Improving Thermoelectric Properties? A Case Study of M0.1Ni0.9Cr2S4 (M = Mn, In)
Does Low‐Level Substitution Aid in Improving Thermoelectric Properties? A Case Study of M0.1Ni0.9Cr2S4 (M = Mn, In)
复制标题
低水平取代有助于提高热电性能吗？
DOI：
10.1002/adem.202100828
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发表时间：
2021
影响因子：
3.6
通讯作者：
L. KienleW. Bensch
中科院分区：
文献类型：
--
作者：
H. Groß;M. Poschmann;D. Groeneveld;J. D. König;L. KienleW. Bensch
用X射线衍射仪和透射电子显微镜研究了场辅助烧结处理的热电材料NiCr2S4中低水平金属阳离子取代对材料性能的影响。NiCr2S4和Mn0.1Ni0.9Cr2S4可以合成成相纯的球团，而In0.1Ni0.9Cr2S4则是不同相的混合物。X射线衍射分析表明，Mn主要以Ni晶格的形式存在，而In主要以附加相的形式存在。NiCr2S4和Mn0.1Ni0.9Cr2S4都形成了一种化学隔离的纳米尺度的磁区结构，这一结构在Mn0.1Ni0.9Cr2S4中表现得更加明显。所有材料的热导率在2 W m−1K−1附近表现出相似的前景，塞贝克系数从−55到−65 μV K−1。只有电导率受到取代的显著影响，原始材料的导热系数最高为504 S cm−1，随后两个取代相的导热系数都有所下降。
The influence of low‐level metal cation substitution in the thermoelectric material NiCr2S4, treated via field‐assisted sintering, is investigated in X‐ray diffraction (XRD) and transmission electron microscopy (TEM) studies. NiCr2S4and Mn0.1Ni0.9Cr2S4can be synthesized and compacted as phase‐pure pellets, while In0.1Ni0.9Cr2S4appears as a mixture of different phases. XRD investigations reveal that Mn can be incorporated into the host material's Ni lattice sites, while In is mainly incorporated into additional phases. Both NiCr2S4and Mn0.1Ni0.9Cr2S4form a structure of chemically segregated, nanoscale domains, which appear significantly more pronounced for Mn0.1Ni0.9Cr2S4. All materials exhibit similar, promising thermal conductivities around 2.0 W m−1K−1, with Seebeck coefficients ranging from −55 to −65 μV K−1. Only the electrical conductivity is noticeably influenced by the substitutions, with the highest value of 504 S cm−1obtained for the pristine material, and subsequently declining for both substituted phases.