| | |
| | |
Stat |
Members: 3645 Articles: 2'500'096 Articles rated: 2609
18 April 2024 |
|
| | | |
|
Article overview
| |
|
Probing efficient n-type lanthanide dopants for Mg$_3$Sb$_2$ thermoelectrics | Jiawei Zhang
; Lirong Song
; Bo Brummerstedt Iversen
; | Date: |
Thu, 27 Aug 2020 09:36:46 GMT (1884kb) | Abstract: | The recent discovery of n-type Mg$_3$Sb$_2$ thermoelectric has ignited
intensive research activities on searching for potential n-type dopants for
this material. Using first-principles defect calculations, here we conduct a
systematic computational screening of potential efficient n-type lanthanide
dopants for Mg$_3$Sb$_2$. In addition to La, Ce, Pr, and Tm, we find that high
electron concentration ($geq$ 10$^{20}$ cm$^{-3}$ at the growth temperature of
900 K) can be achieved by doping on the Mg sites with Nd, Gd, Ho, and Lu, which
are generally more efficient than other lanthanide dopants and the anion-site
dopant Te. Experimentally, we confirm Nd and Tm as effective n-type dopants for
Mg$_3$Sb$_2$ since doping with Nd and Tm shows superior thermoelectric figure
of merit zT $geq$ 1.3 with higher electron concentration than doping with Te.
Through codoping with Nd (Tm) and Te, simultaneous power factor improvement and
thermal conductivity reduction are achieved. As a result, we obtain high zT
values of about 1.65 and 1.75 at 775 K in n-type
Mg$_{3.5}$Nd$_{0.04}$Sb$_{1.97}$Te$_{0.03}$ and
Mg$_{3.5}$Tm$_{0.03}$Sb$_{1.97}$Te$_{0.03}$, respectively, which are among the
highest values for n-type Mg$_3$Sb$_2$ without alloying with Mg$_3$Bi$_2$. This
work sheds light on exploring promising n-type dopants for the design of
Mg$_3$Sb$_2$ thermoelectrics. | Source: | arXiv, 2008.12015 | Services: | Forum | Review | PDF | Favorites |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser claudebot
|
| |
|
|
|
| News, job offers and information for researchers and scientists:
| |