Simulation research on thermal conductivity of thermoelectric material β-Cu<sub>2-<i>x</i></sub>Se
Phonon-liquid thermoelectric material β-Cu<sub>2-<i>x</i></sub>Se can achieve an excellent thermoelectric performance. Molecular dynamic simulations were performed to study the thermal conductivity of β-Cu<sub>2-<i>x</i></sub>Se. The correlation betwee...
| Main Authors: | , |
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| Format: | Article |
| Language: | zho |
| Published: |
Journal of Materials Engineering
2021-02-01
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| Series: | Cailiao gongcheng |
| Subjects: | |
| Online Access: | http://jme.biam.ac.cn/CN/10.11868/j.issn.1001-4381.2020.000077 |
| Summary: | Phonon-liquid thermoelectric material β-Cu<sub>2-<i>x</i></sub>Se can achieve an excellent thermoelectric performance. Molecular dynamic simulations were performed to study the thermal conductivity of β-Cu<sub>2-<i>x</i></sub>Se. The correlation between diffusivity of "liquid-like" ions and the thermal conductivity was analyzed. The effect of doping and vacancies on the material's thermal conductivity was also investigated. The results show that "liquid-like" ion's diffusivity and the thermal conductivity are strongly connected. Enhancement of Cu ions mobility in β-Cu<sub>2-<i>x</i></sub> Se increases the non-harmonic vibration of the crystal lattice, which strengthens the phonon scattering and reduces the thermal conductivity. Doping and vacancies have different influences on "phonon-liquid" materials' thermal conductivity. Vacancies are conducive to the movement of "liquid-like" ions, leading to the decrease in the phonon acoustic branch frequency, which effectively reduce the thermal conductivity. Vacancies may significantly improve "phonon-liquid" materials' thermoelectric conversion efficiency, while the effect of doping on thermal conductivity is not significant. |
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| ISSN: | 1001-4381 1001-4381 |