Thermal stability of p-type skutterudites DD[0.6]Fe[3]CoSb[12] by Knudsen effusion mass
spectrometry



F. Zelenka^1^,2, P. Broz^1,2,*, J. Vrestal^1,2, J. Bursik^3, G. Rogl^4,5, P. Rogl^4,5.

^1 Masaryk University, Faculty of Science, Department of Chemistry, Kotlarska 2, 611 37, Brno,
Czech Republic; ^2 Masaryk University, Central European Institute of Technology, CEITEC, Kamenice
753/5, 625 00, Brno, Czech Republic; ^3 Institute of Physics of Materials, ASCR, Žižkova 22, 616
62, Brno, Czech Republic; ^4 Institute of Materials Chemistry and Research, University of Vienna,
Währingerstraße 42, A-1090 Vienna, Austria; ^5 Christian Doppler Laboratory for Thermoelectricity,
Vienna, Austria

^* The corresponding author e-mail: broz@chemi.muni.cz



Keywords: Thermoelectric materials; Skutterudites; Knudsen effusion mass spectrometry; Thermal
analysis; Scanning electron microscopy



Thermoelectric materials have gained increased interest for their ability to exploit waste heat
(renewable energy) and convert it to electricity in automotive and aerospace industry, electronics
and other areas. The current research, among other materials, is oriented on doped CoSb3 based
skutterudites with high ZT-levels which can further be increased, e.g. by nano-structuring. Current
materials contain volatile elements (Sb, Sr, Yb, etc.), which can evaporate at operation conditions
leading to structure changes, damaging the thermoelectric properties.

The temperature and phase stability of p-type skutterudites DD[0.6]Fe[3]CoSb[12] exhibiting a high
ZT-level have been studied by means of thermal analysis (TA) and Knudsen effusion mass spectrometry
(KEMS). The results from phase transformation measurements and characteristics of evaporation of
the volatile elements supported by microstructure observations and of diffusion profiles are
summarized and discussed in view of a full understanding of the degradation processes and knowledge
on long term operation stability of the bulk and nano-structured thermoelectrics studied.




Acknowledgments

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.