First-principles studies of atomic dynamics in tetrahedrite thermoelectrics
Cu12Sb4S13-based tetrahedrites are high-performance thermoelectrics that contain earth-abundant and environmentally friendly elements. At present, the mechanistic understanding of their low lattice thermal conductivity (<1 W m−1 K−1 at 300 K) remains limited. This work applies first-principles mo...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
AIP Publishing LLC
2016-10-01
|
| Series: | APL Materials |
| Online Access: | http://dx.doi.org/10.1063/1.4959961 |
| _version_ | 1819014554658537472 |
|---|---|
| author | Junchao Li Mengze Zhu Douglas L. Abernathy Xianglin Ke Donald T. Morelli Wei Lai |
| author_facet | Junchao Li Mengze Zhu Douglas L. Abernathy Xianglin Ke Donald T. Morelli Wei Lai |
| author_sort | Junchao Li |
| collection | DOAJ |
| description | Cu12Sb4S13-based tetrahedrites are high-performance thermoelectrics that contain earth-abundant and environmentally friendly elements. At present, the mechanistic understanding of their low lattice thermal conductivity (<1 W m−1 K−1 at 300 K) remains limited. This work applies first-principles molecular dynamics simulations, along with inelastic neutron scattering (INS) experiments, to study the incoherent and coherent atomic dynamics in Cu10.5NiZn0.5Sb4S13, in order to deepen our insight into mechanisms of anomalous dynamic behavior and low lattice thermal conductivity in tetrahedrites. Our study of incoherent dynamics reveals the anomalous “phonon softening upon cooling” behavior commonly observed in inelastic neutron scattering data. By examining the dynamic Cu-Sb distances inside the Sb[CuS3]Sb cage, we ascribe softening to the decreased anharmonic “rattling” of Cu in the cage. On the other hand, our study of coherent dynamics reveals that acoustic modes are confined in a small region of dynamic scattering space, which we hypothesize leads to a minimum phonon mean free path. By assuming a Debye model, we obtain a lattice minimum thermal conductivity value consistent with experiments. We believe this study furthers our understanding of the atomic dynamics of tetrahedrite thermoelectrics and will more generally help shed light on the origin of intrinsically low lattice thermal conductivity in these and other structurally similar materials. |
| first_indexed | 2024-12-21T02:17:41Z |
| format | Article |
| id | doaj.art-8b8e4ad888554f28ba086becdbda7bc7 |
| institution | Directory Open Access Journal |
| issn | 2166-532X |
| language | English |
| last_indexed | 2024-12-21T02:17:41Z |
| publishDate | 2016-10-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | APL Materials |
| spelling | doaj.art-8b8e4ad888554f28ba086becdbda7bc72022-12-21T19:19:14ZengAIP Publishing LLCAPL Materials2166-532X2016-10-01410104811104811-610.1063/1.4959961016695APMFirst-principles studies of atomic dynamics in tetrahedrite thermoelectricsJunchao Li0Mengze Zhu1Douglas L. Abernathy2Xianglin Ke3Donald T. Morelli4Wei Lai5Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USADepartment of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USAQuantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USADepartment of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USADepartment of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USADepartment of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, USACu12Sb4S13-based tetrahedrites are high-performance thermoelectrics that contain earth-abundant and environmentally friendly elements. At present, the mechanistic understanding of their low lattice thermal conductivity (<1 W m−1 K−1 at 300 K) remains limited. This work applies first-principles molecular dynamics simulations, along with inelastic neutron scattering (INS) experiments, to study the incoherent and coherent atomic dynamics in Cu10.5NiZn0.5Sb4S13, in order to deepen our insight into mechanisms of anomalous dynamic behavior and low lattice thermal conductivity in tetrahedrites. Our study of incoherent dynamics reveals the anomalous “phonon softening upon cooling” behavior commonly observed in inelastic neutron scattering data. By examining the dynamic Cu-Sb distances inside the Sb[CuS3]Sb cage, we ascribe softening to the decreased anharmonic “rattling” of Cu in the cage. On the other hand, our study of coherent dynamics reveals that acoustic modes are confined in a small region of dynamic scattering space, which we hypothesize leads to a minimum phonon mean free path. By assuming a Debye model, we obtain a lattice minimum thermal conductivity value consistent with experiments. We believe this study furthers our understanding of the atomic dynamics of tetrahedrite thermoelectrics and will more generally help shed light on the origin of intrinsically low lattice thermal conductivity in these and other structurally similar materials.http://dx.doi.org/10.1063/1.4959961 |
| spellingShingle | Junchao Li Mengze Zhu Douglas L. Abernathy Xianglin Ke Donald T. Morelli Wei Lai First-principles studies of atomic dynamics in tetrahedrite thermoelectrics APL Materials |
| title | First-principles studies of atomic dynamics in tetrahedrite thermoelectrics |
| title_full | First-principles studies of atomic dynamics in tetrahedrite thermoelectrics |
| title_fullStr | First-principles studies of atomic dynamics in tetrahedrite thermoelectrics |
| title_full_unstemmed | First-principles studies of atomic dynamics in tetrahedrite thermoelectrics |
| title_short | First-principles studies of atomic dynamics in tetrahedrite thermoelectrics |
| title_sort | first principles studies of atomic dynamics in tetrahedrite thermoelectrics |
| url | http://dx.doi.org/10.1063/1.4959961 |
| work_keys_str_mv | AT junchaoli firstprinciplesstudiesofatomicdynamicsintetrahedritethermoelectrics AT mengzezhu firstprinciplesstudiesofatomicdynamicsintetrahedritethermoelectrics AT douglaslabernathy firstprinciplesstudiesofatomicdynamicsintetrahedritethermoelectrics AT xianglinke firstprinciplesstudiesofatomicdynamicsintetrahedritethermoelectrics AT donaldtmorelli firstprinciplesstudiesofatomicdynamicsintetrahedritethermoelectrics AT weilai firstprinciplesstudiesofatomicdynamicsintetrahedritethermoelectrics |