Valence fluctuating thermoelectric high-borides with YCrB4 type of structure

• Applicant: Professor Roman Gumeniuk, Ph.D.
• Subject Area: Experimental Condensed Matter Physics ; Solid State and Surface Chemistry, Material Synthesis
• Term: from 2016 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 324961605

The proposed project combines syntheses, characterization, crystal structure refinement as well as study of valence fluctuations and thermoelectric properties of CeCrB4, YbCrB4 and the substitution series Y1-xCexCrB4 and Y1-xYbxCrB4 (x = 0.2, 0.4, 0.6, 0.8) intermetallic borides. Such electron- and hole-doping combined with valence fluctuations of Ce- and Yb-atoms is expected to significantly improve the thermoelectric performance of the semiconducting YCrB4 boride and to obtain a material suitable for the applications in thermoelectrical generators working in high-temperature regime. Joining approaches from solid state chemistry and solid state physics we believe to get deeper insight into the understanding of the interplay between two such phenomena as valence fluctuations and thermoelectricity. Such an understanding will contribute to the development of new routes in the search of boron-based thermoelectric materials.

• DFG Programme: Research Grants