Large Exchange Bias, High Dielectric Constant, and Outstanding Ionic Conductivity in a Single‐Phase Spin Glass

Autor: Mohammad R. Ghazanfari, Archa Santhosh, Konrad Siemensmeyer, Friederike Fuß, Lennart Staab, Johannes C. Vrijmoed, Bertram Peters, Moritz Liesegang, Stefanie Dehnen, Oliver Oeckler, Paul Jerabek, Günther Thiele
Rok vydání: 2022
Předmět:
Zdroj: Ghazanfari, M. R.; Santhosh, A.; Siemensmeyer, K.; Fuß, F.; Staab, L.; Vrijmoed, J. C.; Peters, B.; Liesegang, M.; Dehnen, S.; Oeckler, O.; Jerabek, P.; Thiele, G.: Large Exchange Bias, High Dielectric Constant, and Outstanding Ionic Conductivity in a Single-Phase Spin Glass. In: Advanced Electronic Materials. Vol. 8 (2022) 11, 2200483. (DOI: /10.1002/aelm.202200483)
Advanced Electronic Materials, 8 (11), 2200483
ISSN: 2199-160X
DOI: 10.17169/refubium-36791
Popis: The multigram synthesis of K [Fe S ] starting from K S and FeS is presented, and its electronic and magnetic properties are investigated. The title compound obtains a defect variant of the K[Fe Se ] structure type. Dielectric and impedance measurements indicate a dielectric constant of 1120 at 1 kHz and an outstanding ionic conductivity of 24.37 mS cm at 295 K, which is in the range of the highest reported value for potential solid state electrolytes for potassium ion batteries. The Seebeck coeffcient of the n type conductor amounts to amp; 8722;60 amp; 956;V K at 973 K. The mismatch of the measured electrical resistivity and the predicted metal like band structure by periodic quantum chemical calculations indicates Mott insulating behavior. Magnetometry demonstrates temperature dependent, large exchange biasfields of 35 mT, as a consequence of the coexistence of spin glass and antiferromagnetic orderings due to the iron vacancies in the lattice. In addition, the decreasing training effects of 34 in the exchange bias are identified at temperatures lower than 20 K. These results demonstrate the critical role of iron vacancies in tuning the electronic and magnetic properties and a multifunctional material from abundant and accessible elements
Databáze: OpenAIRE
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