The Thermoelectric Properties of n-Type Bismuth Telluride: Bismuth Selenide Alloys Bi2Te3−xSex
| Autor: | Thomas C. Chasapis, Ian T. Witting, Geoffroy Hautier, G. Jeffrey Snyder, Francesco Ricci |
|---|---|
| Přispěvatelé: | UCL - SST/IMCN/MODL - Modelling |
| Rok vydání: | 2020 |
| Předmět: |
Antimony telluride
Multidisciplinary Materials science Phonon scattering Condensed matter physics Science Alloy 02 engineering and technology engineering.material 021001 nanoscience & nanotechnology 01 natural sciences Condensed Matter::Materials Science chemistry.chemical_compound Chalcogen Effective mass (solid-state physics) chemistry 0103 physical sciences Thermoelectric effect engineering Bismuth telluride Bismuth selenide 010306 general physics 0210 nano-technology |
| Zdroj: | Research, Vol 2020 (2020) Research, Vol. 2020, no.-, p. 1-15 (2020) |
| ISSN: | 2639-5274 |
| DOI: | 10.34133/2020/4361703 |
| Popis: | Alloying bismuth telluride with antimony telluride and bismuth selenide for p - and n -type materials, respectively, improves the thermoelectric quality factor for use in room temperature modules. As the electronic and thermal transports can vary substantially, the alloy composition is a key engineering parameter. The n -type Bi 2 Te 3- x Se x alloy lags its p -type counterpart in thermoelectric performance and does not lend itself as readily to simple transport modeling which complicates engineering. Combining literature data with recent results across the entire alloy composition range, the complex electronic structure dynamics and trends in lattice thermal conductivity are explored. Spin-orbit interaction plays a critical role in determining the position and degeneracy of the various conduction band minima. This behavior is incorporated into a two-band effective mass model to estimate the transport parameters in each band. An alloy scattering model is utilized to demonstrate how phonon scattering behaves differently on either side of the intermediate ordered compound Bi 2 Te 2 Se due to chalcogen site occupancy preference. The parametrization of the electronic and thermal transports presented can be used in future optimization efforts. |
| Databáze: | OpenAIRE |
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