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In this paper, we explore the structural, electronic, thermoelectric and elastic properties of intermetallic compounds ScTM (TM = Cu, Ag, Au and Pd) using density functional theory. The produced results show high values of Seebeck coefficients and electrical conductivity for these materials. High power factor for these materials at room-temperature shows that these materials may be beneficial for low-temperature thermoelectric devices and alternative energy sources. Furthermore, elastic properties of these compounds are also calculated, which are used to evaluate their mechanical properties. The Cauchy’s pressure and B/G ratio figure out that these compounds are ductile in nature. The calculated results also predict that these compounds are stable against deforming force.

The doping and temperature dependent thermopower of SnTe is calculated from the first principles band structure using Boltzmann transport theory. We find that the p-type thermopower is inferior to PbTe consistent with experimental observations, but that the n-type thermopower is substantially more favorable.

In the investigation of thermoelectric (TE) materials as a practical, and efficient, means of power generation/ refrigeration nearly ninety percent of the possible high-efficient binary compounds have been evaluated. But only a few proved to be useful such as Bi₂Te₃ alloys, PbTe and SiGe to name the most important materials. Therefore, in order to expand the research of high-efficiency TE materials new compounds and methods of efficiency optimization must be explored. There currently exist a vast number of uninvestigated ternary and quaternary materials that could be potential high-efficiency thermoelectric materials. The device and methodology discussed herein deal with rapidly measuring both the electrical resistivity and the Seebeck coefficient of thermoelectric materials, at a set temperature of T ≈ 300 K. Using nontraditional resistivity measurements and rapid, room-temperature thermopower measurements, a reliable and time-efficient means of gauging the power factor (defined below) values of newly synthesized thermoelectric materials is achievable. Furthermore, the efficacy of the van der Pauw technique for measuring the resistivity of thermoelectric materials has been verified.

In this paper, we describe the synthesis and characterization of the solid solution Cu₂Zn_1-xFe_xGeSe₄. Electronic transport data have been analyzed using a single parabolic band model and have been compared to Cu_2+xZn_1-xGeSe₄. The effective mass of these undoped, intrinsically hole conducting materials increases linearly with increasing carrier concentration, showing a non-parabolic transport behavior within the valence band.

The electric and thermoelectric properties of novel, CdTe/PbTe layered nanocomposite material are investigated. The molecular beam epitaxy (MBE) method was used for preparation of samples with well controlled distances (from 20 to 70 nm) between the layers of CdTe nanograins embedded in PbTe thermoelectric matrix as well as with number of these layers from 2 to 10. The Hall effect measurements performed in temperature range from 4–300 K revealed that carrier mobility is strongly affected by scattering on CdTe grain boundaries. The observation of Shubnikov-de Haas oscillations confirms high quality of the samples and allows determination of effective mass of conducting electrons m* = 0.04m₀. The measurements of the room temperature Seebeck coefficient together with electrical conductivity lead to the power factors which are comparable to those reported in PbTe/CdTe polycrystalline solid solutions.