TY - JOUR

T1 - Triple-phase ceramic 2D nanocomposite with enhanced thermoelectric properties

AU - Bittner, Michael

AU - Kanas, Nikola

AU - Hinterding, Richard

AU - Steinbach, Frank

AU - Groeneveld, Dennis

AU - Wemhoff, Piotr

AU - Wiik, Kjell

AU - Einarsrud, Mari Ann

AU - Feldhoff, Armin

N1 - Funding information: This work has been funded by the Deutsche Forschungsgesellschaft (DFG, German Research Foundation) – FE928/17-1. Financial support from The Research Council of Norway is appreciated under the program Nano2021 to the project (Number 228854) “Thermoelectric materials: Nanostructuring for improving the energy efficiency of thermoelectric generators and heat-pumps” (THELMA). Thanks are to the E.ON Stipendienfonds (T0087 – ESF) for financing the academic exchange between the Norwegian University for Science and Technology (NTNU) and the Gottfried Wilhelm Leibniz University Hannover.

PY - 2019/4

Y1 - 2019/4

N2 - A thermoelectric triple-phase p-type Ca3Co4O9-NaxCoO2-Bi2Ca2Co2O9 (CCO–NCO–BCCO) 2D nanocomposite was obtained from pressureless sintering in air. The anisotropic thermoelectric properties of the nanocomposite exhibit a high electrical conductivity of 116 S cm−1 and a power factor of 6.5 μW cm−1 K−2 perpendicular to the pressing direction at 1073 K in air. A corresponding zT value of 0.35 was obtained. Three co-doped, thermoelectrically active misfit-layered materials were stacked to form a triple-phase nanocomposite, which combines the advantages of all three materials. The resulting nanocomposite enables simultaneous increases of the isothermal electrical conductivity σ and the Seebeck coefficient α by charge carrier concentration engineering and synergistic effects. The Bi2Ca2Co2O9 and NaxCoO2 phases were stabilized in a Ca3Co4O9 matrix at high temperatures. To evaluate the application of the nanocomposite in high-temperature thermoelectric generators, the representation of the electrical conductivity and power factor in a Ioffe plot was more appropriate than the zT value.

AB - A thermoelectric triple-phase p-type Ca3Co4O9-NaxCoO2-Bi2Ca2Co2O9 (CCO–NCO–BCCO) 2D nanocomposite was obtained from pressureless sintering in air. The anisotropic thermoelectric properties of the nanocomposite exhibit a high electrical conductivity of 116 S cm−1 and a power factor of 6.5 μW cm−1 K−2 perpendicular to the pressing direction at 1073 K in air. A corresponding zT value of 0.35 was obtained. Three co-doped, thermoelectrically active misfit-layered materials were stacked to form a triple-phase nanocomposite, which combines the advantages of all three materials. The resulting nanocomposite enables simultaneous increases of the isothermal electrical conductivity σ and the Seebeck coefficient α by charge carrier concentration engineering and synergistic effects. The Bi2Ca2Co2O9 and NaxCoO2 phases were stabilized in a Ca3Co4O9 matrix at high temperatures. To evaluate the application of the nanocomposite in high-temperature thermoelectric generators, the representation of the electrical conductivity and power factor in a Ioffe plot was more appropriate than the zT value.

KW - 2D nanostructures

KW - All-scale hierarchical architecture

KW - CaCoO

KW - Nanocomposite

KW - Thermoelectricity

UR - http://www.scopus.com/inward/record.url?scp=85056457922&partnerID=8YFLogxK

U2 - 10.1016/j.jeurceramsoc.2018.10.023

DO - 10.1016/j.jeurceramsoc.2018.10.023

M3 - Article

AN - SCOPUS:85056457922

VL - 39

SP - 1237

EP - 1244

JO - Journal of the European Ceramic Society

JF - Journal of the European Ceramic Society

SN - 0955-2219

IS - 4

ER -