Investigation on the Thermoelectric and Structural Properties of Cobalt-Antimony based Skutterudites and Modifications with Indium and Rare-Earth Elements
- The thesis investigates on the thermoelectric and structural properties of CoSb3 skutterudite material. The material was modified by several elements such as indium, cerium and gadolinium, which have a significant impact on the crystal structure and moreover on the thermoelectric properties. The CoSb3 skutterudite material was synthesized by induction melting and subsequent long-term annealing mostly from elementary constituents. Series of indium filled (In:CoSb3), cerium and indium (Ce,In:CoSb3) and gadolinium and indium (Gd,In:CoSb3) specimens with different concentrations of the additional elements (In, Ce, Gd) were prepared for structural investigations and (high temperature) thermoelectric characterization.
Structural investigations with high resolution neutron powder diffraction were carried out on the Skutterudite material to determine the atom positions and the thermal parameters of the constituents.
The indium single filled skutterudite material shows promisingThe thesis investigates on the thermoelectric and structural properties of CoSb3 skutterudite material. The material was modified by several elements such as indium, cerium and gadolinium, which have a significant impact on the crystal structure and moreover on the thermoelectric properties. The CoSb3 skutterudite material was synthesized by induction melting and subsequent long-term annealing mostly from elementary constituents. Series of indium filled (In:CoSb3), cerium and indium (Ce,In:CoSb3) and gadolinium and indium (Gd,In:CoSb3) specimens with different concentrations of the additional elements (In, Ce, Gd) were prepared for structural investigations and (high temperature) thermoelectric characterization.
Structural investigations with high resolution neutron powder diffraction were carried out on the Skutterudite material to determine the atom positions and the thermal parameters of the constituents.
The indium single filled skutterudite material shows promising thermoelectric properties within the temperature range of 300 K and 700 K. Indium acts as a so-called filler element and the forming secondary phases can contribute to an enhanced figure of merit ZT, when the synthesis and annealing parameters are optimized.
Double filling of the skutterudite material further enhances the lattice thermal resistivity with a concomitant high Seebeck coefficient and electrical conductivity, especially for cerium and indium.…