Related papers: Achieving ultra-high power factor in Sb2Te2Se via …
Density functional calculations have performed to study the band structures of $Bi_2Te_3$-related binary ($Bi_2Te_3$, $Sb_2Te_3$, $Bi_2Se_3$, and $Sb_2Se_3$) and $Sb$/$Se$ doped ternary compounds [$(Bi_{1-x}Sb_x)_2Te_3$ and…
Improving the figure of merit $zT$ of thermoelectric materials requires simultaneously a high power factor and low thermal conductivity. An effective approach for increasing the power factor is to align the band extremum and achieve high…
Band alignment (or band convergence) is a strategy suggested to provide improvements in the thermoelectric power factor (PF) of materials with complex bandstructures. The addition of more bands at the energy region that contributes to…
The electronic and thermoelectric properties of one to four monolayers of MoS$_{2}$, MoSe$_{2}$, WS$_{2}$, and WSe$_{2}$ are calculated. For few layer thicknesses,the near degeneracies of the conduction band $K$ and $\Sigma$ valleys and the…
The Mg2X (X=Si, Ge, Sn) based alloy is an eco-friendly thermoelectric material for mid-temperature applications. The Mg2Si1-xSnx and Mg2Ge1-xSnx alloys can be phase-separated into Si(Ge)- and Sn-rich phases during material synthesis,…
Band convergence is an effective strategy to improve the thermoelectric performance of complex bandstructure thermoelectric materials. Half-Heuslers are good candidates for band convergence studies because they have multiple bands near the…
We have investigated the valley degeneracy of MoS2 multilayers and its effect on thermoelectric properties. By modulating the layer thickness and external electric field, the hole valleys at {\Gamma} and K points in the highest energy…
Rock-salt structured chalcogenides, such as PbTe, PbSe, and SnTe, are the top candidates for mid-temperature thermoelectric applications, and their p-type thermoelectric efficiencies can be enhanced via aligning the valence bands. Here, we…
Materials with ring-shaped electronic bands are promising thermoelectric candidates, since their unusual dispersion shape is predicted to give large power factors. While previous calculations of these materials have relied on the assumption…
IV-VI semiconductor SnSe has been known as the material with record high thermoelectric performance.The multiple close-to-degenerate valence bands in the electronic band structure has been one of the key factors contributing to the high…
Low band gap thermoelectric materials suffer from bipolar effects at high temperatures, with increased electronic thermal conductivity and reduced Seebeck coefficient, leading to reduced power factor and low ZT figure of merit. In this work…
The electronic, phonon, and thermoelectric properties of a two-dimensional HfS2 monolayer are investigated by using the first-principles calculations combined with the Boltzmann transport theory. The band valleys of the HfS2 monolayer can…
Achieving high valley degeneracy (i.e. "band convergence") in a material usually results in considerably enhanced thermoelectric properties. However, it is still unclear why this strategy of designing efficient thermoelectric materials is…
Thermoelectric (TE) materials are useful for applications such as waste heat harvesting or efficient and targeted cooling. While various strategies towards superior thermoelectrics through a reduction of the lattice thermal conductivity…
SnTe is a potential thermoelectric material in the mid temperature range. Detailed techniques to enhance the figure of merit by increasing the Power Factor, and reducing thermal conductivity, of SnTe-based TE materials are discussed. The…
Half-Heuslers, an emerging thermoelectric material group, has complex bandstructures with multiple bands that can be aligned through band engineering approaches, giving us an opportunity to improve their power factor. In this work, going…
Efficient thermoelectric materials should present large Seebeck coefficient, high electrical conductivity and low thermal conductivity. An enhanced Seebeck coefficient can be obtained from materials where the Fermi level can be aligned with…
The energy spectrum of the valence band in HgTe/Cd$_x$Hg$_{1-x}$Te quantum wells with a width $(8-20)$~nm has been studied experimentally by magnetotransport effects and theoretically in framework $4$-bands $kP$-method. Comparison of the…
We investigate the thermoelectric properties of CaAl$_2$Si$_2$-type Zintl phase compounds $AB_2X_2$ ($A$ = Mg, Ca, Sr, Ba, $B$ = Mg, Zn, Cd, and $X$ = P, As, Sb) using first principles band calculations within the Boltzmann transport theory…
We investigate optimal band structures in band-converged systems to achieve high zT using numerical calculations based on a virtual spectral conductivity model. We consider a two parabolic band system, in which multiple band parameters can…