Structural Complexity and Thermoelectric Properties of Quaternary and Quinary Tellurides (GexSn1-x)(0.8)(InySb1-y)(0.13)Te with 0 x,y 1

Neudert, Lukas; Schwarzmüller, Stefan; Scheel, Manuel; Welzmiller, Simon und Öckler, Oliver (2017): Structural Complexity and Thermoelectric Properties of Quaternary and Quinary Tellurides (GexSn1-x)(0.8)(InySb1-y)(0.13)Te with 0 x,y 1. In: Zeitschrift für Anorganische und Allgemeine Chemie, Bd. 643, Nr. 23: S. 1962-1970

Abstract

Starting from stoichiometric mixtures of the elements, quaternary and quinary solid solutions (GexSn1-x)(0.8)(InySb1-y)(0.13)Te were obtained. Concerning the ratio Ge/Sn and Sb/In, respectively, lattice parameters of the metastable phases with rocksalt-type average structures approximately obey Vegard's law. Stable phases correspond to a disordered rocksalt type at high temperature and to trigonal layered structures with van der Waal gaps at lower temperature as shown by temperature-dependent powder X-ray diffraction combined with TEM, which reveals layer-like vacancy ordering, whose extent depends on composition and thermal treatment. In the long-periodically ordered model compounds 21R-Ge0.5Sn0.5InSbTe4 and 9P-GeSnInSbTe5 studied by resonant scattering data at K-absorption edges, Sb and Sn concentrate near the van der Waals gaps. Compared to Ge0.8Sb0.13Te and Sn0.8Sb0.13Te, the simultaneous presence of In and Sn combines increased electrical conductivity with low thermal conductivity and enhanced thermoelectric properties in certain temperature ranges. Phase transitions correlate with changes of the thermoelectric properties.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Chemie und Pharmazie > Department Chemie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 0044-2313
• Sprache: Englisch