Study of thermal stability of doped CoSb based skutterudites by
Knudsen effusion mass spectrometry
F. Zelenkaa,b
, P. Broža,b
, J. Vřešťála,b
, J. Buršíkc
, G. Rogld,e
, P. Rogld,e
a
Masaryk University, Central European Institute of Technology, CEITEC, Kamenice
753/5, 62500, Brno, Czech Republic
b
Masaryk University, Faculty of Science, Department of Chemistry, Kotlářská 2,
61137, Brno, Czech Republic
c
Institute of Physics of Materials, Czech Academy of Sciences, Žižkova 22, 61662,
Brno, Czech Republic
d
Institute of Materials Chemistry and Research, University of Vienna,
Währingerstraße 42, A-1090 Vienna, Austria
e
Christian Doppler Laboratory for Thermoelectricity, Vienna, Austria
Study in the field of thermoelectric materials is of great importance because these
materials are able to directly convert thermal energy into electrical energy (Seebeck
effect, 1821; thermoelectric generator) and reversibly electrical energy into thermal
energy (Peltier effect, 1835; thermoelectric heat pump or Peltier cooling). The current
research, among other materials, is oriented on doped CoSb based skutterudites with
high ZT-levels which can further be increased, e.g. by nano-structuring. Various ways
in preparation of this kind of materials, as described e.g. in [1], [2], imply differences
in thermoelectric efficiency which also depends on the thermal stability of the
materials.
Thermal and phase stability of selected doped multicomponent CoSb based
skutterudites from macrocrystaline to nano-structured form have been studied using
methods of thermal analysis (TA) and Knudsen effusion mass spectrometry (KEMS).
The measurements have been performed on a Netzsch STA 409 CD/3/403/5/G
apparatus, a specially-adapted type of the commercial STA 409 CD - QMS 403/5
Skimmer Coupling Instrument, described in [3], [4]. The results of TA and KEMS
measurements, including data on phase transformations and evaporation
characteristics of volatile elements, supported by measurements of diffusion profiles
are summarized and discussed in view of a full understanding of the degradation
processes.
The work has been supported by the Czech Science Foundation under the project
GA 17-12844S as well as by the project CEITEC 2020 (LQ1601) from the Ministry of
Education, Youth and Sports of the Czech Republic under the National Sustainability
Programme II.
[1] Schierning G. et al., Translational Materials Research, 2 (2015) 025001
[2] Zhang L. et al., Journal of Alloys and Compounds, 481 (2009) 106-115.
[3] Brož P. et al., ECS Transactions, 46 (2013) 69-76.
[4] Brož P. et al., International Journal of Mass Spectrometry, 383 (2015) 13-22.