Ba₅Cu₈In₂S₁₂: a quaternary semiconductor with a unique 3D copper-rich framework and ultralow thermal conductivity

Abstract

A novel quaternary sulfide, BaCuInS (1), has been successfully synthesized via a high-temperature solid-state reaction. It contains CuSS clusters as basic building blocks, which are connected to one another by discrete In ions to generate a 3D copper-rich framework, where the Ba cations reside. Interestingly, such large clusters that are fused by five crystallographically independent Cu sites with three different chemical environments result in the increase of phonon scattering, which is the crucial factor to the exceptionally low lattice thermal conductivity (ca. 0.28 W m K at 773 K) in 1.

CsCu3SbS4: rational design of a two-dimensional layered material with giant birefringence derived from Cu3SbS4

“…The detailed bond lengths and angles are summarized in Table S4. † The Cu-S bond lengths range from 2.260(4) Å to 2.281(6) Å with an average distance of 2.269 Å, and are comparable to those in CsCu 5 S 3 (2.210-2.396 Å), 26 Ba 5 Cu 8 In 2 S 12 (2.254-2.332 Å), 27 and Rb 2 CuSb 7 S 12 (2.278-2.404 Å). 25 The Sb-S distances in 3-coordinated triangular pyramids are in the range of 2.419(4)-2.421(6) Å, similar to those in the reported thioantimonates (e.g., 2.374-2.502 Å in Cs 2 Cu 2 Sb 2 S 5 , 20 2.411-2.423 Å in A 2 Ba 3 Cu 2 Sb 2 S 10 , 28 and 2.400-2.489 Å in K 2 Ag 3 Sb 3 S 7 29 ).…”

Synthesis, Crystal Structure, and Physical Properties of BaSnS2

“…The bond distances range from 3.059(18) to 3.277(19) Å and from 2.642(19) to 2.677(18) Å for Ba–S and Sn–S, respectively. These bond distances are typical for Ba–S bonds of octahedrally coordinated Ba 2+ atoms, such as in Ba 5 Cu 8 In 2 S 12 , [ 39 ] and Sn–S bonds for trigonally coordinated Sn 2+ atoms, such as in Ba 7 Sn 5 S 15 . [ 40 ]…”

High Thermoelectric Performance in the New Cubic Semiconductor AgSnSbSe3 by High-Entropy Engineering

“…Established routes to achieve low κlat include: (1) enhancing phonon scattering through the introduction of point defects, 2 nanostructures 3 and all-scale hierarchical architec-tures; [4][5] and (2) exploring new materials with inherently low lattice thermal conductivity, typically originating from complex crystal structures and strong lattice anharmonicity. 6 Examples of the second approach include In4Se3, 7 Ag9GaSe6 8 , Sb2Si2Te6 3 , AgCuTe 9 , Ba5Cu8In2S12 10 and SnSe. [11][12][13][14] SnSe is a rapidly emerging thermoelectric compound.…”