The Effect of Reactive Electric Field-Assisted Sintering of MoS(2)/Bi(2)Te(3) Heterostructure on the Phase Integrity of Bi(2)Te(3) Matrix and the Thermoelectric Properties

In this work, a series of Bi(2)Te(3)/X mol% MoS(2) (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 Bi(2)Te(3)/MoS(2) heterostructure, are highly reactive during the electric field-assisted sintering by SPS. The nano-sized MoS(2) particles react with the Bi(2)Te(3) plates matrix forming a mixed-anion compound, Bi(2)Te(2)S, 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 Bi(2)Te(3) matrix. As a result, enhanced ZT values have been obtained in Bi(2)Te(3)/25 mol% MoS(2) over the temperature range of 300–475 K induced mainly by a significant increase in the electrical conductivity.