High Thermoelectric Performance Achieved in Sb-Doped GeTe by Manipulating Carrier Concentration and Nanoscale Twin Grains

Lead-free and eco-friendly GeTe shows promising mid-temperature thermoelectric applications. However, a low Seebeck coefficient due to its intrinsically high hole concentration induced by Ge vacancies, and a relatively high thermal conductivity result in inferior thermoelectric performance in pristine GeTe. Extrinsic dopants such as Sb, Bi, and Y could play a crucial role in regulating the hole concentration of GeTe because of their different valence states as cations and high solubility in GeTe. Here we investigate the thermoelectric performance of GeTe upon Sb doping, and demonstrate a high maximum zT value up to 1.88 in Ge0.90Sb0.10Te as a result of the significant suppression in thermal conductivity while maintaining a high power factor. The maintained high power factor is due to the markable enhancement in the Seebeck coefficient, which could be attributed to the significant suppression of hole concentration and the valence band convergence upon Sb doping, while the low thermal conductivity stems from the suppression of electronic thermal conductivity due to the increase in electrical resistivity and the lowering of lattice thermal conductivity through strengthening the phonon scattering by lattice distortion, dislocations, and twin boundaries. The excellent thermoelectric performance of Ge0.90Sb0.10Te shows good reproducibility and thermal stability. This work confirms that Ge0.90Sb0.10Te is a superior thermoelectric material for practical application.

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High Thermoelectric Performance Achieved in Sb-doped GeTe by Manipulating Carrier Concentration and Nanoscale Twin Grains

10.21203/rs.3.rs-612367/v1 ◽

2021 ◽

Author(s):

Chao Li ◽

Haili Song ◽

Lei Miao ◽

Chengqiang Cui ◽

Chengyan Liu ◽

...

Keyword(s):

Thermal Conductivity ◽

Power Factor ◽

High Power ◽

Thermoelectric Performance ◽

Significant Suppression ◽

Practical Application ◽

Promising Candidate ◽

High Power Factor ◽

High Maximum ◽

Sb Doping

Abstract Lead-free and eco-friendly GeTe shows a promising candidate for mid-temperature thermoelectric application. However, a low Seebeck coefficient due to its intrinsically high holes concentration that induced by Ge vacancies, and a relatively high thermal conductivity result in an inferior thermoelectric performance of pristine GeTe. However, extrinsic atoms Sb, Bi, and Y could play a crucial role in regulating the holes concentration of GeTe because of their relatively high solubility. Here we investigate the thermoelectric performance of the GeTe upon Sb doping, and demonstrate a high maximum zT value up to 1.88 could be achieved in Ge 0.90 Sb 0.10 Te as a result of the significant suppression in thermal conductivity while holding a high power factor. Where the maintained high power factor is due to the markable enhancement in S , which could be attributed to the significant suppression of holes concentration and the valence band convergence upon Sb doping; while the low thermal conductivity stems from the suppression of electronic thermal conductivity due to the increase in electrical resistivity and the lowering of lattice thermal conductivity through strengthening the phonons scattering by the lattice distortion, dislocations, and twin boundaries. Aside from the excellent thermoelectric performance, Ge 0.90 Sb 0.10 Te also shows good reproducibility, as well as thermal stability. This work confirms the Ge 0.90 Sb 0.10 Te is a superior thermoelectric material for practical application.

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A High Thermoelectric Performance ZT in p-Type LaSe2 Crystal

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.871.203 ◽

2021 ◽

Vol 871 ◽

pp. 203-207

Author(s):

Jian Liu

Keyword(s):

Thermal Conductivity ◽

Power Factor ◽

High Power ◽

Density Functional ◽

Lattice Thermal Conductivity ◽

Phonon Transport ◽

Thermoelectric Performance ◽

Boltzmann Transport ◽

High Power Factor ◽

P Type

In this work, we use first principles DFT calculations, anharmonic phonon scatter theory and Boltzmann transport method, to predict a comprehensive study on the thermoelectric properties as electronic and phonon transport of layered LaSe2 crystal. The flat-and-dispersive type band structure of LaSe2 crystal offers a high power factor. In the other hand, low lattice thermal conductivity is revealed in LaSe2 semiconductor, combined with its high power factor, the LaSe2 crystal is considered a promising thermoelectric material. It is demonstrated that p-type LaSe2 could be optimized to exhibit outstanding thermoelectric performance with a maximum ZT value of 1.41 at 1100K. Explored by density functional theory calculations, the high ZT value is due to its high Seebeck coefficient S, high electrical conductivity, and low lattice thermal conductivity .

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High thermoelectric performance of superionic argyrodite compound Ag8SnSe6

Journal of Materials Chemistry C ◽

10.1039/c6tc00810k ◽

2016 ◽

Vol 4 (24) ◽

pp. 5806-5813 ◽

Cited By ~ 44

Author(s):

Lin Li ◽

Yuan Liu ◽

Jiyan Dai ◽

Aijun Hong ◽

Min Zeng ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermoelectric Material ◽

Power Factor ◽

High Power ◽

Figure Of Merit ◽

Environmentally Friendly ◽

Thermoelectric Performance ◽

Low Thermal Conductivity ◽

High Power Factor ◽

High Figure

A good thermoelectric material usually has a high power factor and low thermal conductivity for high figure of merit (ZT), and is also environmentally friendly and economical.

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Thermoelectric Performance of ZrNX (X = Cl, Br, I) Monolayers

Physical Chemistry Chemical Physics ◽

10.1039/d1cp01928g ◽

2021 ◽

Author(s):

Wenwu Shi ◽

Nina Ge ◽

Xinzhong Wang ◽

Zhiguo Wang

Keyword(s):

Thermal Conductivity ◽

Power Factor ◽

High Power ◽

Thermoelectric Materials ◽

Lattice Thermal Conductivity ◽

Thermoelectric Performance ◽

Low Thermal Conductivity ◽

High Power Factor

Low thermal conductivity and high power factor are essential for the efficient thermoelectric materials. The lattice thermal conductivity can be reduced by reducing the dimension of materials, thus improving the...

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