Ab-initio investigation on the electronic and thermoelectric properties of new half-Heusler compounds KBiX (X = Ba and Sr)

Abstract

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Electronic Structure-, Phonon Spectrum-, and Effective Mass- Related Thermoelectric Properties of PdXSn (X = Zr, Hf) Half Heuslers

“…Figure 6 represents the Seebeck coefficient ( S ), electrical conductivity ( ), and electronic thermal conductivity ( ) for both PdZrSn and PdHfSn materials at various temperatures (300 K, 500 K, 700 K). According to Mott’s formula [ 27 ], the Seebeck coefficient is directly proportional to DOS effective mass and temperature but inversely proportional to carrier concentration. It is given by …”

“…Thermoelectric properties of KBiX (X = Ba, Sr) were investigated by Z.F. Meghoufel et al using ab initio principle, and they found the values of ZT = 2.68 and 1.56 for KBiBa and KBiSr, respectively [ 27 ]. R. Ahemad et al reported ZT = 1 for all XMgN (X = Li, La, K) half Heusler materials [ 28 ].…”

Exploring structural, mechanical, and thermoelectric properties of half-Heusler compounds RhBiX (X = Ti, Zr, Hf): A first-principles investigation

“… 29 For KBiX (X = Ba, Sr), based on theoretical calculation, ZT reached 2.68 (1.56) for KBiBa (KBiSr). 30 J. Carrete used an ab initio method to screen a batch of structurally stable HH compounds and predicted that the materials had small lattice thermal conductivity. 31 J. H. Liu applied a compressed-sensing approach to evaluate the lattice thermal conductivity with significantly high accuracy, 32 where RhBiX (X = Ti, Zr, Hf) was within the range of their predicted HH compounds.…”

Effect of Strain on the Electronic Structure and Phonon Stability of SrBaSn Half Heusler Alloy

“…Later, the different moduli (B and V) are determined from the Voigt-Reuss-Hill approximations (VRH) [34,35], where B, G, Y, longitudinal (𝒗 𝒍 ) and transverse(𝒗 𝒕 ) velocities are written as [36] B =…”

“…Elastic constants in Table 1 computed for the SrBaSn alloy in its type-2-type groundstate stable structure include (C 11 , C 12, and C 44 ), shear (G)/bulk (B)/Young (Y)) moduli, Poisson's (ν), Pugh ratio (B/G), etc. Stability criterion proposed by Born-Huang [33] presumes the mechanical stability of SrBaSn in its Heusler structure form and is written in the form Later, the different moduli (B and V) are determined from the Voigt-Reuss-Hill approximations (VRH) [34,35], where B, G, Y, longitudinal (v l ) and transverse (v t ) velocities are written as [36]…”