Enhanced thermoelectric properties of solution grown Bi2Te3–xSex nanoplatelet composites
We report on the enhanced thermoelectric properties of selenium (Se) doped bismuth telluride (Bi2Te3–xSex) nanoplatelet (NP) composites synthesized by the polyol method. Variation of the Se composition within NPs is demonstrated by X-ray diffraction and Raman spectroscopy. While the calculated latti...
| Main Authors: | , , , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2013
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| Online Access: | https://hdl.handle.net/10356/97155 http://hdl.handle.net/10220/10714 |
| _version_ | 1826118064348856320 |
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| author | Dresselhaus, Mildred S. Ligen, Yu Soni, Ajay Yanyuan, Zhao Aik, Michael Khor Khiam Xiong, Qihua |
| author2 | School of Electrical and Electronic Engineering |
| author_facet | School of Electrical and Electronic Engineering Dresselhaus, Mildred S. Ligen, Yu Soni, Ajay Yanyuan, Zhao Aik, Michael Khor Khiam Xiong, Qihua |
| author_sort | Dresselhaus, Mildred S. |
| collection | NTU |
| description | We report on the enhanced thermoelectric properties of selenium (Se) doped bismuth telluride (Bi2Te3–xSex) nanoplatelet (NP) composites synthesized by the polyol method. Variation of the Se composition within NPs is demonstrated by X-ray diffraction and Raman spectroscopy. While the calculated lattice parameters closely follow the Vegard’s law, a discontinuity in the shifting of the high frequency (Eg2 and A1g2) phonon modes illustrates a two mode behavior for Bi2Te3–xSex NPs. The electrical resistivity (ρ) of spark plasma sintered pellet composites shows metallic conduction for pure Bi2Te3 NP composites and semiconducting behavior for intermediate Se compositions. The thermal conductivity (κ) for all NP composites is much smaller than the bulk values and is dominated by microstructural grain boundary scattering. With temperature dependent electrical and thermal transport measurements, we show that both the thermoelectric power S (−259 μV/K) and the figure of merit ZT (0.54) are enhanced by nearly a factor of 4 for SPS pellets of Bi2Te2.7Se0.3 in comparison to Bi2Te3 NP composites. Tentatively, such an enhancement of the thermoelectric performance in nanoplatelet composites is attributed to the energy filtering of low energy electrons by abundant grain boundaries in aligned nanocomposites. |
| first_indexed | 2024-10-01T04:37:37Z |
| format | Journal Article |
| id | ntu-10356/97155 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T04:37:37Z |
| publishDate | 2013 |
| record_format | dspace |
| spelling | ntu-10356/971552020-03-07T12:34:40Z Enhanced thermoelectric properties of solution grown Bi2Te3–xSex nanoplatelet composites Dresselhaus, Mildred S. Ligen, Yu Soni, Ajay Yanyuan, Zhao Aik, Michael Khor Khiam Xiong, Qihua School of Electrical and Electronic Engineering School of Mechanical and Aerospace Engineering School of Physical and Mathematical Sciences We report on the enhanced thermoelectric properties of selenium (Se) doped bismuth telluride (Bi2Te3–xSex) nanoplatelet (NP) composites synthesized by the polyol method. Variation of the Se composition within NPs is demonstrated by X-ray diffraction and Raman spectroscopy. While the calculated lattice parameters closely follow the Vegard’s law, a discontinuity in the shifting of the high frequency (Eg2 and A1g2) phonon modes illustrates a two mode behavior for Bi2Te3–xSex NPs. The electrical resistivity (ρ) of spark plasma sintered pellet composites shows metallic conduction for pure Bi2Te3 NP composites and semiconducting behavior for intermediate Se compositions. The thermal conductivity (κ) for all NP composites is much smaller than the bulk values and is dominated by microstructural grain boundary scattering. With temperature dependent electrical and thermal transport measurements, we show that both the thermoelectric power S (−259 μV/K) and the figure of merit ZT (0.54) are enhanced by nearly a factor of 4 for SPS pellets of Bi2Te2.7Se0.3 in comparison to Bi2Te3 NP composites. Tentatively, such an enhancement of the thermoelectric performance in nanoplatelet composites is attributed to the energy filtering of low energy electrons by abundant grain boundaries in aligned nanocomposites. 2013-06-26T06:28:57Z 2019-12-06T19:39:28Z 2013-06-26T06:28:57Z 2019-12-06T19:39:28Z 2012 2012 Journal Article Soni, A., Yanyuan, Z., Ligen, Y., Aik, M. K. K., Dresselhaus, M. S., & Xiong, Q. (2012). Enhanced Thermoelectric Properties of Solution Grown Bi2Te3–xSex Nanoplatelet Composites. Nano Letters, 12(3), 1203-1209. 1530-6984 https://hdl.handle.net/10356/97155 http://hdl.handle.net/10220/10714 10.1021/nl2034859 en Nano letters © 2012 American Chemical Society. |
| spellingShingle | Dresselhaus, Mildred S. Ligen, Yu Soni, Ajay Yanyuan, Zhao Aik, Michael Khor Khiam Xiong, Qihua Enhanced thermoelectric properties of solution grown Bi2Te3–xSex nanoplatelet composites |
| title | Enhanced thermoelectric properties of solution grown Bi2Te3–xSex nanoplatelet composites |
| title_full | Enhanced thermoelectric properties of solution grown Bi2Te3–xSex nanoplatelet composites |
| title_fullStr | Enhanced thermoelectric properties of solution grown Bi2Te3–xSex nanoplatelet composites |
| title_full_unstemmed | Enhanced thermoelectric properties of solution grown Bi2Te3–xSex nanoplatelet composites |
| title_short | Enhanced thermoelectric properties of solution grown Bi2Te3–xSex nanoplatelet composites |
| title_sort | enhanced thermoelectric properties of solution grown bi2te3 xsex nanoplatelet composites |
| url | https://hdl.handle.net/10356/97155 http://hdl.handle.net/10220/10714 |
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