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The Effect of Reactive Electric Field-Assisted Sintering of MoS₂/Bi₂Te₃ Heterostructure on the Phase Integrity of Bi₂Te₃ Matrix and the Thermoelectric Properties.

ABSTRACT: In this work, a series of Bi₂Te₃/X mol% MoS₂ (X = 0, 25, 50, 75) bulk nanocomposites were prepared by hydrothermal reaction followed by reactive spark plasma sintering (SPS). X-ray diffraction analysis (XRD) indicates that the native nanopowders, comprising of Bi₂Te₃/MoS₂ heterostructure, are highly reactive during the electric field-assisted sintering by SPS. The nano-sized MoS₂ particles react with the Bi₂Te₃ plates matrix forming a mixed-anion compound, Bi₂Te₂S, at the interface between the nanoplates. The transport properties characterizations revealed a significant influence of the nanocomposite structure formation on the native electrical conductivity, Seebeck coefficient, and thermal conductivity of the initial Bi₂Te₃ matrix. As a result, enhanced ZT values have been obtained in Bi₂Te₃/25 mol% MoS₂ over the temperature range of 300-475 K induced mainly by a significant increase in the electrical conductivity.

SUBMITTER: Wang Y

PROVIDER: S-EPMC8746225 | biostudies-literature |

REPOSITORIES: biostudies-literature

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