Effect of metal doping on the low-temperature structural behavior of thermoelectric β-Zn 4 Sb 3

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@article{31fa258e69804835a60c59c2ead85483,
title = "Effect of metal doping on the low-temperature structural behavior of thermoelectric β-Zn 4 Sb 3",
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′, 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 .",
keywords = "Order-disorder structural transitions, Temperature polymorphism, Thermoelectric materials, Zinc antimonides",
author = "Johanna Nyl{\'e}n and Sven Lidin and Magnus Andersson and Hongxue Liu and Nate Newman and Ulrich H{\"a}ussermann",
year = "2007",
month = sep,
day = "1",
doi = "10.1016/j.jssc.2007.07.013",
language = "English",
volume = "180",
pages = "2603--2615",
journal = "Journal of Solid State Chemistry",
issn = "0022-4596",
publisher = "Elsevier",
number = "9",

}