Spinodal decomposition in (CaxBa1-x)(y)Fe4Sb12

Autor(en)

Gerda Rogl, Andrij Grytsiv, Matthias Falmbigl, Ernst Bauer, Clemens Mangler, Christian Rentenberger, Michael Zehetbauer, Peter Franz Rogl

Abstrakt

The thermoelectric and structural properties of a double filled skutterudite solid solution (CaxBa1-x)(y)Fe4Sb12 were investigated. Using X-ray powder and X-ray micro analyses (EPMA) an immiscibility gap was established with a critical point at x approximate to 0.45 and a critical temperature that depends on the filling level (T-C = 590 +/- 5 degrees C at y = 0.8 and T-C = 610 +/- 5 degrees C at y = 0.9). The thermoelectric properties were measured for samples prepared in four different states: (i) a single phase solid solution (CaxBa1-x)(5)Fe4Sb12; (ii) a two phase microcrystalline mixture of CayFe4Sb12 and BayFe4Sb12; (iii) a single phase structure obtained after annealing of the latter sample at 600 degrees C for 200 h; (iv) a spinodally demixed sample after annealing at 400 degrees C for 672 h. The thermoelectric properties of the phase mixture (ii) are compatible with data reported for the microcrystalline end members (CayFe4Sb12 and BayFe4Sb12), whilst the single phase (i and iii) and spinodally decomposed (iv) samples show increased thermopower and decreased thermal conductivity, similarly to those observed for nano-structured CayFe4Sb12 and BayFe4Sb12.

Organisation(en)

Institut für Physikalische Chemie, Physik Nanostrukturierter Materialien

Externe Organisation(en)

Arizona State University

Journal

Acta Materialia

Band

60

Seiten

4487-4495

Anzahl der Seiten

9

ISSN

1359-6454

DOI

https://doi.org/10.1016/j.actamat.2012.04.038

Publikationsdatum

2012

Peer-reviewed

Ja

ÖFOS 2012

1030 Physik, Astronomie, 104006 Festkörperchemie, 505036 Energierecht, 103018 Materialphysik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/b7aa8f21-8bc2-4e60-bdb2-61a3a87f6c36