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Intrinsic nanostructure induced ultralow thermal conductivity yields enhanced thermoelectric performance in Zintl phase Eu₂ZnSb₂.

ABSTRACT: The Zintl thermoelectric phase Eu₂ZnSb₂ has a remarkable combination of high mobility and low thermal conductivity that leads to good thermoelectric performance. The key feature of this compound is a crystal structure that has a Zn-site with a 50% occupancy. Here we use comparison of experimental thermal conductivity measurements and first principles thermal conductivity calculations to characterize the thermal conductivity reduction. We find that partial ordering, characterized by local order, but Zn-site disorder on longer scales, leads to an intrinsic nanostructuring induced reduction in thermal conductivity, while retaining electron mobility. This provides a direction for identifying Zintl compounds with ultralow lattice thermal conductivity and good electrical conductivity.

SUBMITTER: Chen C

PROVIDER: S-EPMC8481231 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Intrinsic nanostructure induced ultralow thermal conductivity yields enhanced thermoelectric performance in Zintl phase Eu2ZnSb2.

Chen Chen C Feng Zhenzhen Z Yao Honghao H Cao Feng F Lei Bing-Hua BH Wang Yumei Y Chen Yue Y Singh David J DJ Zhang Qian Q

Nature communications 20210929 1

The Zintl thermoelectric phase Eu2ZnSb2 has a remarkable combination of high mobility and low thermal conductivity that leads to good thermoelectric performance. The key feature of this compound is a crystal structure that has a Zn-site with a 50% occupancy. Here we use comparison of experimental thermal conductivity measurements and first principles thermal conductivity calculations to characterize the thermal conductivity reduction. We find that partial ordering, characte ...[more]

PMID: 34588464

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