Effect of metal doping on the low-temperature structural behavior of thermoelectric β-Zn 4 Sb 3
(2007) In Journal of Solid State Chemistry 180(9). p.2603-2615- Abstract
The low-temperature structural phase transitions of Bi, Pb, In and Sn-doped samples of thermoelectric Zn
4
Sb
3
have been characterized on crystals grown from molten metal fluxes, using electrical resistance and single crystal X-ray diffraction measurements. Room temperature stable, disordered, β-Zn
4
Sb
3
undergoes two phase transitions at 254 and 235 K to the consecutively higher ordered phases α and α′,... (More)
(Less)
The low-temperature structural phase transitions of Bi, Pb, In and Sn-doped samples of thermoelectric Zn
4
Sb
3
have been characterized on crystals grown from molten metal fluxes, using electrical resistance and single crystal X-ray diffraction measurements. Room temperature stable, disordered, β-Zn
4
Sb
3
undergoes two phase transitions at 254 and 235 K to the consecutively higher ordered phases α and α′, respectively. The ideal crystallographic composition of α-Zn
4
Sb
3
is Zn
13
Sb
10
. The α-α′ transformation is triggered by a slight and homogenous Zn deficiency with respect to this composition and introduces a compositional modulation in the α-Zn
4
Sb
3
structure. When preparing β-Zn
4
Sb
3
in the presence of metals with low melting points (Bi, Sn, In, Pb) the additional metal atoms are unavoidably incorporated in small concentrations (0.04-1.3 at%) and act as dopants. This incorporation alters the subtle balance between Zn disorder and Zn deficiency in Zn
4
Sb
3
and has dramatic consequences for its low-temperature structural behavior. From molten metal flux synthesis it is possible to obtain (doped) Zn
4
Sb
3
samples which (1) only display a β-α transition, (2) only display a β-α′ transition, or (3) do not display any low-temperature phase transition at all. Case (2) provided diffraction data with a sufficient quality to obtain a structural model for highly complex, compositionally modulated, α′-Zn
4
Sb
3
. The crystallographic composition of this phase is Zn
84
Sb
65
.
- author
- Nylén, Johanna ; Lidin, Sven LU ; Andersson, Magnus LU ; Liu, Hongxue ; Newman, Nate and Häussermann, Ulrich
- organization
- publishing date
- 2007-09-01
- type
- Contribution to journal
- publication status
- published
- keywords
- Order-disorder structural transitions, Temperature polymorphism, Thermoelectric materials, Zinc antimonides
- in
- Journal of Solid State Chemistry
- volume
- 180
- issue
- 9
- pages
- 13 pages
- publisher
- Elsevier
- external identifiers
-
- scopus:34548425737
- ISSN
- 0022-4596
- DOI
- 10.1016/j.jssc.2007.07.013
- language
- English
- LU publication?
- yes
- id
- 31fa258e-6980-4835-a60c-59c2ead85483
- date added to LUP
- 2019-04-08 15:14:01
- date last changed
- 2022-01-31 18:46:46
@article{31fa258e-6980-4835-a60c-59c2ead85483,
abstract = {{<p><br>
The low-temperature structural phase transitions of Bi, Pb, In and Sn-doped samples of thermoelectric Zn<br>
<sub>4</sub><br>
Sb<br>
<sub>3</sub><br>
have been characterized on crystals grown from molten metal fluxes, using electrical resistance and single crystal X-ray diffraction measurements. Room temperature stable, disordered, β-Zn<br>
<sub>4</sub><br>
Sb<br>
<sub>3</sub><br>
undergoes two phase transitions at 254 and 235 K to the consecutively higher ordered phases α and α′, respectively. The ideal crystallographic composition of α-Zn<br>
<sub>4</sub><br>
Sb<br>
<sub>3</sub><br>
is Zn<br>
<sub>13</sub><br>
Sb<br>
<sub>10</sub><br>
. The α-α′ transformation is triggered by a slight and homogenous Zn deficiency with respect to this composition and introduces a compositional modulation in the α-Zn<br>
<sub>4</sub><br>
Sb<br>
<sub>3</sub><br>
structure. When preparing β-Zn<br>
<sub>4</sub><br>
Sb<br>
<sub>3</sub><br>
in the presence of metals with low melting points (Bi, Sn, In, Pb) the additional metal atoms are unavoidably incorporated in small concentrations (0.04-1.3 at%) and act as dopants. This incorporation alters the subtle balance between Zn disorder and Zn deficiency in Zn<br>
<sub>4</sub><br>
Sb<br>
<sub>3</sub><br>
and has dramatic consequences for its low-temperature structural behavior. From molten metal flux synthesis it is possible to obtain (doped) Zn<br>
<sub>4</sub><br>
Sb<br>
<sub>3</sub><br>
samples which (1) only display a β-α transition, (2) only display a β-α′ transition, or (3) do not display any low-temperature phase transition at all. Case (2) provided diffraction data with a sufficient quality to obtain a structural model for highly complex, compositionally modulated, α′-Zn<br>
<sub>4</sub><br>
Sb<br>
<sub>3</sub><br>
. The crystallographic composition of this phase is Zn<br>
<sub>84</sub><br>
Sb<br>
<sub>65</sub><br>
.</p>}},
author = {{Nylén, Johanna and Lidin, Sven and Andersson, Magnus and Liu, Hongxue and Newman, Nate and Häussermann, Ulrich}},
issn = {{0022-4596}},
keywords = {{Order-disorder structural transitions; Temperature polymorphism; Thermoelectric materials; Zinc antimonides}},
language = {{eng}},
month = {{09}},
number = {{9}},
pages = {{2603--2615}},
publisher = {{Elsevier}},
series = {{Journal of Solid State Chemistry}},
title = {{Effect of metal doping on the low-temperature structural behavior of thermoelectric β-Zn
<sub>4</sub>
Sb
<sub>3</sub>}},
url = {{http://dx.doi.org/10.1016/j.jssc.2007.07.013}},
doi = {{10.1016/j.jssc.2007.07.013}},
volume = {{180}},
year = {{2007}},
}