Substitutional and interstitial impurity p-type doping of thermoelectric Mg2Si: a theoretical study
The narrow-gap magnesium silicide semiconductor Mg2Si is a promising mid-temperature (600–900 K) thermoelectric material. It intrinsically possesses n-type conductivity, and n-type dopants are generally used for improving its thermoelectric performance; however, the synthesis of p-type Mg2Si is rela...
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| Format: | Article |
| Language: | English |
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Taylor & Francis Group
2019-12-01
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| Series: | Science and Technology of Advanced Materials |
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| Online Access: | http://dx.doi.org/10.1080/14686996.2019.1580537 |
| _version_ | 1818318828818399232 |
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| author | Naomi Hirayama Tsutomu Iida Mariko Sakamoto Keishi Nishio Noriaki Hamada |
| author_facet | Naomi Hirayama Tsutomu Iida Mariko Sakamoto Keishi Nishio Noriaki Hamada |
| author_sort | Naomi Hirayama |
| collection | DOAJ |
| description | The narrow-gap magnesium silicide semiconductor Mg2Si is a promising mid-temperature (600–900 K) thermoelectric material. It intrinsically possesses n-type conductivity, and n-type dopants are generally used for improving its thermoelectric performance; however, the synthesis of p-type Mg2Si is relatively difficult. In this work, the hole doping of Mg2Si with various impurity atoms is investigated by performing first principles calculations. It is found that the Ag-doped systems exhibit comparable formation energies ΔE calculated for different impurity sites (Mg, Si, and interstitial 4b ones), which may explain the experimental instability of their p-type conductivity. A similar phenomenon is observed for the systems incorporating alkali metals (Li, Na, and K) since their ΔE values determined for Mg (p-type) and 4b (n-type) sites are very close. Among boron group elements (Ga and B), Ga is found to be favorable for hole doping because it exhibits relatively small ΔE values for Si (p-type) sites. Furthermore, the interstitial insertion of Cl and F atoms into the crystal lattice leads to hole doping because of their high electronegativity. |
| first_indexed | 2024-12-13T09:59:26Z |
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| id | doaj.art-e93037654e6e44fbaeb8c7246046323f |
| institution | Directory Open Access Journal |
| issn | 1468-6996 1878-5514 |
| language | English |
| last_indexed | 2024-12-13T09:59:26Z |
| publishDate | 2019-12-01 |
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| series | Science and Technology of Advanced Materials |
| spelling | doaj.art-e93037654e6e44fbaeb8c7246046323f2022-12-21T23:51:43ZengTaylor & Francis GroupScience and Technology of Advanced Materials1468-69961878-55142019-12-0120116017210.1080/14686996.2019.15805371580537Substitutional and interstitial impurity p-type doping of thermoelectric Mg2Si: a theoretical studyNaomi Hirayama0Tsutomu Iida1Mariko SakamotoKeishi Nishio2Noriaki Hamada3Osaka UniversityTokyo University of ScienceTokyo University of ScienceOsaka UniversityThe narrow-gap magnesium silicide semiconductor Mg2Si is a promising mid-temperature (600–900 K) thermoelectric material. It intrinsically possesses n-type conductivity, and n-type dopants are generally used for improving its thermoelectric performance; however, the synthesis of p-type Mg2Si is relatively difficult. In this work, the hole doping of Mg2Si with various impurity atoms is investigated by performing first principles calculations. It is found that the Ag-doped systems exhibit comparable formation energies ΔE calculated for different impurity sites (Mg, Si, and interstitial 4b ones), which may explain the experimental instability of their p-type conductivity. A similar phenomenon is observed for the systems incorporating alkali metals (Li, Na, and K) since their ΔE values determined for Mg (p-type) and 4b (n-type) sites are very close. Among boron group elements (Ga and B), Ga is found to be favorable for hole doping because it exhibits relatively small ΔE values for Si (p-type) sites. Furthermore, the interstitial insertion of Cl and F atoms into the crystal lattice leads to hole doping because of their high electronegativity.http://dx.doi.org/10.1080/14686996.2019.1580537magnesium silicidehole dopingthermoelectric propertiesinterstitial insertionp-type semiconductorstructural stability |
| spellingShingle | Naomi Hirayama Tsutomu Iida Mariko Sakamoto Keishi Nishio Noriaki Hamada Substitutional and interstitial impurity p-type doping of thermoelectric Mg2Si: a theoretical study Science and Technology of Advanced Materials magnesium silicide hole doping thermoelectric properties interstitial insertion p-type semiconductor structural stability |
| title | Substitutional and interstitial impurity p-type doping of thermoelectric Mg2Si: a theoretical study |
| title_full | Substitutional and interstitial impurity p-type doping of thermoelectric Mg2Si: a theoretical study |
| title_fullStr | Substitutional and interstitial impurity p-type doping of thermoelectric Mg2Si: a theoretical study |
| title_full_unstemmed | Substitutional and interstitial impurity p-type doping of thermoelectric Mg2Si: a theoretical study |
| title_short | Substitutional and interstitial impurity p-type doping of thermoelectric Mg2Si: a theoretical study |
| title_sort | substitutional and interstitial impurity p type doping of thermoelectric mg2si a theoretical study |
| topic | magnesium silicide hole doping thermoelectric properties interstitial insertion p-type semiconductor structural stability |
| url | http://dx.doi.org/10.1080/14686996.2019.1580537 |
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