Ca₄Sb₂O and Ca₄Bi₂O: two promising mixed-anion thermoelectrics

Abstract

The environmental burden of fossil fuels and the rising impact of global warming have created an urgent need for sustainable clean energy sources. This has led to widespread interest in...

Remarkable Thermoelectric Performance in K2CdPb Crystals with 1D Building Blocks via Structure Particularity and Bond Heterogeneity

“…Figure and Figure S5 show the separated scattering rates and mobility of K 2 CdSn and K 2 CdPb limited by ionized impurity, acoustic deformation potential, and polar optical phonon scattering. We see that the room temperature carriers in both systems are dominated by polar optical phonon scattering at 10 19 cm 3 , which agrees with the behavior in polar semiconductors. ,− In addition, some of the best-performing thermoelectrics such as SnSe and PbTe have also shown a similar phenomenon. , On the other hand, the contribution of acoustic phonon scattering is minimal, which results in its higher carrier mobility among the three scattering processes, as shown in Figure c,d (Figure S5c,d). From the above discussion, we can infer that mobility obtained based on the deformation potential theory may be somewhat overestimated in polar semiconductors, which is in good agreement with previous work .…”

Structural Dynamics and Thermal Transport in Bismuth Chalcogenide Alloys

“…Thermoelectrics are attractive candidates for modeling because the terms in eq are amenable to calculation. The electrical properties can be predicted using semiclassical Boltzmann transport theory, , and it has also recently become possible to model the structural dynamics and to predict the lattice thermal conductivity. − The latter has been instrumental to understanding the intrinsic anharmonicity in materials with low κ latt , ,,− including several flagship TEs, ,,, and has also been used to identify novel candidate TEs. , There are several reports of modeling studies on bulk bismuth chalcogenides − and their nanostructures (e.g., single layers), − including a handful of studies of the structural dynamics and thermal conductivity. ,− Modeling studies on alloys are however rarer, due to the more complex calculations involved, and tend to be restricted to compositions with well-defined structures. ,, …”

“…27−30 The latter has been instrumental to understanding the intrinsic anharmonicity in materials with low κ latt , 11,14,31−35 including several flagship TEs, 11,12,14,33 and has also been used to identify novel candidate TEs. 34,35 There are several reports of modeling studies on bulk bismuth chalcogenides 36−40 and their nanostructures (e.g., single layers), 41−44 including a handful of studies of the structural dynamics and thermal conductivity. 37,41−44 Modeling studies on alloys are however rarer, due to the more complex calculations involved, and tend to be restricted to compositions with well-defined structures.…”

Antibonding p-d and s-p Hybridization Induce the Optimization of Thermal and Thermoelectric Performance of MGeTe3 (M = In and Sb)

“…The accuracy of this method has been confirmed by comparison with state-of-the-art electron–phonon coupling results []. In addition, a great deal of work on (Ba, Sr)­SnS 3 [], K 2 CdPb [], CuTaS 3 [], Ca 4 (Sb, Bi) 2 O [], and Cs 3 Cu 2 I 5 [] using the same scheme to estimate the transport properties of the compounds also establishes the applicability of this approach to our system. We adopt a 12 × 12 × 9 k -mesh and mBJ-corrected functional to determine the wavefunction and energy eigenvalues.…”