1. CuPbBi5S9 thermoelectric material with an intrinsic low thermal conductivity: Synthesis and properties
- Author
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Zhen-Hua Ge, Jing Feng, Yunxuan Zhou, Hao Liang, Jun Guo, and Zi-Yuan Wang
- Subjects
Materials science ,Anharmonicity ,Metals and Alloys ,Thermodynamics ,02 engineering and technology ,Grüneisen parameter ,Atmospheric temperature range ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Thermoelectric materials ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,symbols.namesake ,Thermal conductivity ,symbols ,Figure of merit ,Density functional theory ,0210 nano-technology ,Debye model - Abstract
CuPbBi5S9 compounds have been investigated as gladite for years. However, there have been no significant studies on their physical and chemical properties. This work demonstrates that upon alloying with moderate Cu, Pb, Bi, and S using an appropriate preparation method, quaternary CuPbBi5S9 compounds can exhibit excellent figure of merit ZT within the temperature range 298–723 K. A low average velocity, low Young’s modulus and Debye temperature, and large Gruneisen parameter, determined experimentally, indicate strong lattice anharmonicity in CuPbBi5S9 crystals. Furthermore, density functional theory calculations (local vibration of low-frequency acoustic phonons) justify the low lattice thermal conductivity of CuPbBi5S9 compounds. Because of the low thermal conductivity (0.514 W m−1K−1) and a relatively high power factor (293 μW m−1K−2), a maximum ZT of 0.42 was achieved at 723 K for CuPbBi5S9 prepared by mechanical alloying combined with solid-state melting. Thus, CuPbBi5S9 materials are promising candidates for use as high-performance thermoelectric materials in the intermediate-temperature range.
- Published
- 2022