Thermal transport properties of anisotropic materials RbCaX (X = As, Sb) with strong anharmonicity

High thermoelectric performance in XAgSe2 (X = Sc, Y) from strong quartic anharmonicity and multi-valley band structure

“…‡ Compared to optical phonon modes, acoustic phonon modes exhibit larger g, indicating stronger cubic anharmonicity. 39 This outcome is consistent with our prior analysis that the rattling behavior of the Ag atom dominating the low-frequency phonon mode has stronger anharmonicity. Simultaneously, the scattering phase space reects the scattering probability and also explains the origin of the high anharmonic phonon scattering rates [see Fig.…”

Strong anharmonicity and high thermoelectric performance of cubic thallium-based fluoride perovskites TlXF3 (X = Hg, Sn, Pb)

“…To improve the ZT value, the power factor (PF), defined as S 2 s, can be increased by methods such as carrier energy filtering 8,9 and band alignment. 10 Furthermore, reducing the thermal conductivity through the use of sublattice disorder, 11 nanostructures, 12 and anharmonicity, [13][14][15] among other techniques, can significantly improve thermoelectric performance. Therefore, an optimal TE material should have the properties of a phonon-glass electroncrystal, 16 that is, have poor thermal conductivity and good electrical conductivity at the same time.…”

Novel room-temperature full-Heusler thermoelectric material Li2TlSb

“…The phonon frequencies harden overall by the SCP theory calculation, especially for the high-frequency optical phonon branches, while the acoustic phonon and low-frequency optical phonon branches have smaller shifts. 61 It is noteworthy that the present study neglected the cubic anharmonicity effects on phonon frequencies, as they are typically less significant and negative (Δ q < 0) compared to the quartic anharmonicity. 62 As shown in Table S3 (ESI†), we selected the phonon modes of the acoustic branch LA at the high symmetry points X and K , and calculated the phonon frequencies considering the cubic anharmonicity using the self-consistent phonon theory.…”