An Efficient Strategy for Searching High Lattice Thermal Conductivity Materials

Abstract

Searching for high thermal conductivity materials to efficiently conduct heat for various applications is a long-term endeavor. In 1973, Slack gave four rules for a material with high thermal conductivity, including low atomic mass, strong interatomic bonds, simple crystal structure, and low lattice anharmonicity. Comparing the thermal conductivities of 5 carbon allotropes carefully selected from the Carbon Allotrope Database, we found that a high symmetry operation number SO or a small atom number n in the primitive unit cell can significantly reduce the phonon−phonon scattering phase space. Based on SO and n, we comprehensively searched the Database of 803 carbon allotropes and found that the bcc-C6 allotrope has a high thermal conductivity owing to its high SO of 96 and small n of 6. The calculated lattice thermal conductivity of bcc-C6 can reach 2198 W/m K at room temperature if its atomic packing fraction equals that of diamond. Our findings indicate that high crystal symmetry can be employed as an efficient strategy to search for materials with high thermal conductivity.

Intervalley scattering induced significant reduction in lattice thermal conductivities for phosphorene

“…Actually, studies have shown that symmetry breaking can significantly reduce the phonon degeneracy and enhance the avoid-crossing behavior of phonon branches, which results in an increase in the phonon-phonon scattering phase space to limit lattice heat transport. 26,27 The optimized lattice constants are 3.28 Å and 4.12 Å for b-P and b-Sb, respectively, which are in good agreement with the previous work. 28,29 The calculated band structures are shown in Fig.…”

Prediction of novel ground-state structures and analysis of phonon transport in two-dimensional GexSy compounds

“…2(c), due to the greater number of atoms in the primitive unit cell of GeS 2 , increasing the probability of phonon–phonon scattering. 53 Furthermore, the higher phase space [as observed in Fig. 9(e)] of GeS 2 in the frequency range of 150 cm −1 supports our argument regarding its considerable anisotropic κ l , attributed to both acoustic and low-frequency optical phonons within the 50–150 cm −1 frequency range.…”

A stable trigon-based 3D carbon allotrope with ultralow lattice thermal conductivity

“…63 Compared to conventional carbon structures with high thermal conductivity, carbon materials with ultralow thermal conductivity are desirable in many thermal management applications where heat transfer needs to be minimized to improve the working performance and reliability of electronic devices without overheating and thermal damages. 64 For the convenience of comparison, we summarize the thermal conductivities of Tri-C 20 and some 3D carbon allotropes, including diamond, 59,60 Bcc-C6, 65 graphite, 57,58 lonsdaleite, 66 etc. with respect to their number of atoms and symmetry group numbers in Fig.…”