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Zintl-phase Eu2ZnSb2: A promising thermoelectric material with ultralow thermal conductivity.

ABSTRACT: Zintl compounds are considered to be potential thermoelectric materials due to their "phonon glass electron crystal" (PGEC) structure. A promising Zintl-phase thermoelectric material, 2-1-2-type Eu2ZnSb2 (P63/mmc), was prepared and investigated. The extremely low lattice thermal conductivity is attributed to the external Eu atomic layers inserted in the [Zn2Sb2]2- network in the structure of 1-2-2-type EuZn2Sb2 [Formula: see text], as well as the abundant inversion domain boundary. By regulating the Zn deficiency, the electrical properties are significantly enhanced, and the maximum ZT value reaches ?1.0 at 823 K for Eu2Zn0.98Sb2 Our discovery provides a class of Zintl thermoelectric materials applicable in the medium-temperature range.

SUBMITTER: Chen C

PROVIDER: S-EPMC6386660 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Zintl-phase Eu2ZnSb2: A promising thermoelectric material with ultralow thermal conductivity.

Chen Chen C Xue Wenhua W Li Shan S Zhang Zongwei Z Li Xiaofang X Wang Xinyu X Liu Yijie Y Sui Jiehe J Liu Xingjun X Cao Feng F Ren Zhifeng Z Chu Ching-Wu CW Wang Yumei Y Zhang Qian Q

Proceedings of the National Academy of Sciences of the United States of America 20190204 8

Zintl compounds are considered to be potential thermoelectric materials due to their "phonon glass electron crystal" (PGEC) structure. A promising Zintl-phase thermoelectric material, 2-1-2-type Eu2ZnSb2 (P63/mmc), was prepared and investigated. The extremely low lattice thermal conductivity is attributed to the external Eu atomic layers inserted in the [Zn2Sb2]2- network in the structure of 1-2-2-type EuZn2</su ...[more]

PMID: 30718395

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