The electrical properties of the entropy stabilized oxides: Zr6Nb2O17, Zr6Ta2O17, Hf6Nb2O17and Hf6Ta2O17were characterized. The results and the electrical properties of the products (i.e. ZrO2, HfO2, Nb2O5and Ta2O5) led us to hypothesize the A6B2O17family is a series of mixed ionic-electronic conductors. Conductivity measurements in varying oxygen partial pressure were performed on A6Nb2O17and A6Ta2O17.The results indicate that electrons are involved in conduction in A6Nb2O17while holes play a role in conduction of A6Ta2O17. Between 900 °C–950 °C, the charge transport in the A6B2O17system increases in Ar atmosphere. A combination of DTA/DSC and in situ high temperature X-ray diffraction was performed to identify a potential mechanism for this increase. In-situ high temperature X-ray diffraction in Ar does not show any phase transformation. Based on this, it is hypothesized that a change in the oxygen sub-lattice is the cause for the shift in high temperature conduction above 900 °C–950 °C. This could be:
- Award ID(s):
- 2021871
- NSF-PAR ID:
- 10523448
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-3660-3
- Page Range / eLocation ID:
- 1 to 2
- Subject(s) / Keyword(s):
- Heating systems Spectroscopy Lattices Nonlinear optical devices Optical materials Photoconductivity Transient analysis
- Format(s):
- Medium: X
- Location:
- Montreal, QC, Canada
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/IRMMW-THz57677.2023.10298923
