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Co-regulation of the copper vacancy concentration and point defects leading to the enhanced thermoelectric performance of Cu₃In₅Te₉-based chalcogenides.

ABSTRACT: Copper vacancy concentration (V _c) in ternary Cu-In-Te chalcogenides is an important factor to engineer carrier concentration (n _H) and thermoelectric performance. However, it is not sufficient to regulate the phonon scattering in the Cu₃In₅Te₉-based chalcogenides. In this work we manipulate the V _c value and point defects simultaneously through addition of Cu along with Ga substitution for In in Cu₃In₅Te₉, and thereby increase the carrier concentration and reduce the lattice thermal conductivity. This strategy finally enables us to achieve ∼60% enhancement of the TE figure of merit (ZT) at V _c = 0.078 compared with the pristine Cu₃In₅Te₉. It is also used as guidance to achieve the high TE performance of the ternary chalcogenides.

SUBMITTER: Li M

PROVIDER: S-EPMC9072708 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Co-regulation of the copper vacancy concentration and point defects leading to the enhanced thermoelectric performance of Cu3In5Te9-based chalcogenides.

Li Min M Luo Yong Y Hu Xiaojuan X Han Zhongkang Z Liu Xianglian X Cui Jiaolin J

RSC advances 20191007 54

Copper vacancy concentration (V c) in ternary Cu-In-Te chalcogenides is an important factor to engineer carrier concentration (n H) and thermoelectric performance. However, it is not sufficient to regulate the phonon scattering in the Cu3In5Te9-based chalcogenides. In this work we manipulate the V c value and point defects simultaneously through addition of Cu along with Ga substitution for In in Cu3</sub ...[more]

PMID: 35527929

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