High-Throughput Screening of Rattling-Induced Ultralow Lattice Thermal Conductivity in Semiconductors

Abstract

Thermoelectric (TE) materials with rattling model show ultralow lattice thermal conductivity for high-efficient energy conversion between heat and electricity. In this work, by analysis of the key spirit of the rattling model, we propose an efficient empirical descriptor to realize the high-throughput screening of ultralow thermal conductivity in a series of semiconductors. This descriptor extracts the structural information of rattling atoms whose bond lengths with all the nearest neighboring atoms are larger than the sum of corresponding covalent radiuses. We obtain 1171 candidates from the Materials Project (MP) Database that contains more than 100 000 materials. Combining the empirical equation of high-throughput computation with a machine learning algorithm, we compute the approximate lattice thermal conductivities (κL) and find the κL values of 532 materials are less than 2.0 W m–1 K–1 at 300 K, which can be regarded as the criteria of ultralow κL in general. In particular, we demonstrate that halide double perovskites structures show ultralow κL, which provides valuable references for promising low κL materials in future experiments. In order to further verify our computational results, we calculate accurate κL for Rb2SnBr6 and CsCu3O2 as candidates with the low lattice thermal conductivity by solving the phonon Boltzmann transport equation. In particular, we demonstrate that Rb2SnBr6 has the lowest κL value of 0.1 W m–1 K–1 at 300 K of all known thermal conductivity materials with the rattling model so far.

Strong Anharmonicity‐Induced Low Thermal Conductivity and High n‐type Mobility in the Topological Insulator Bi1.1Sb0.9Te2S

“…[1] The k lat being the only independent parameter in the zT equation, discovering new materials having intrinsically low k lat is imperative to achieve high thermoelectric performance. [8][9][10] Several fascinating chemical and physical phenomenon of materials such as strong lattice anharmonicity [11][12][13] , rattling of atoms, [14][15][16][17][18][19] cation-anion disordering [20] off centering atom, [21][22][23] presence of liquid-like sublattices, [24,25] metavalent bonding [26,27] and ferroelectric instability [28] are found to play a vital role for obtaining intrinsically low k lat . To explore new materials with low k lat , a detailed understanding of the relationship among the crystal structure, chemical bonding, and lattice dynamics is essential.…”

Enhanced Electron–Phonon Coupling Effect in Rare-Earth Borate Crystals Containing a “Quasi-Free-Oxygen” Motif

“…LCB crystallized in monoclinic space group C2 with unit cell parameters of a = 11.043 Å, b = 6.563 Å, c = 9.129 Å, β = 91.47°, and Z = 2. 27 As shown in Figure 2a, the basis structural unit of the LCB crystal is the (B 5 O 12 ) 9− double-ring pentaborate group, which is built from two triangular (BO 3 ) 3− units and three tetrahedral (BO 4 ) 5 All of the infinite two-dimensional (2D) planes are superimposed with each other along the c direction to form a three-dimensional structure. When Gd 3+ was introduced, it could occupy the La 3+ or Ca 2+ site simultaneously with partial disorder.…”

“…The physical interaction between electron states and lattice vibrations, namely, electron–phonon coupling, is the cornerstone of many intriguing phenomena comprising superconductivity, Jahn–Teller distortion, charge density waves, etc. − Therefore, it is very meaningful to elucidate the electron–phonon coupling dependence on the crystal structure, especially the rare-earth (RE) photofunctional materials. , Photoluminescence is a common method to study electron–phonon coupling because lattice vibrations can greatly modulate the electron transitions, accompanied by phonon creation or annihilation . Consequently, the luminescence wavelength can be regulated by red shift (or blue shift) by phonon creation (or annihilation).…”

Physical Insights on the Thermoelectric Performance of Cs2SnBr6 with Ultralow Lattice Thermal Conductivity

“…These two kinds of anharmonic vibrations trigger additional scattering between phonons, resulting in low lattice thermal conductivity. 4 (LA) phonon mode and the low-lying optical phonon mode within the range of 0.5−0.7 THz are present (highlighted by black circles). This phenomenon is due to the existence of rattling modes in the material, leading to strong anharmonic vibrations.…”

“…Recently, vacancy-ordered double perovskites A 2 BX 6 have been gaining attention for thermoelectric energy conversion due to unique structural attributes and ultralow lattice thermal conductivity. − Researchers have found that Cs 2 SnI 6 is a good n -type thermoelectric material due to its lattice thermal conductivity of 0.29–0.22 W m –1 K –1 in an air-stable environment . Sajjad et al studied the electron and phonon transport properties of Cs 2 PtI 6 and found that heavy elements can act as phonons to effectively suppress the lattice thermal conductivity (0.15 W m –1 K –1 at room temperature) .…”