Yang, F. orcid.org/0000-0002-6428-7755, Du, Y., Hu, Y. et al. (3 more authors) (2023) Mixed ionic–electronic conduction and defect chemistry of (Na0.5Bi0.5TiO3)1−x(BiCoO3)x (0 ≤ x ≤ 0.06) solid solutions. Journal of Materials Chemistry A, 11 (30). pp. 16159-16171. ISSN 2050-7488
Abstract
The electrical conductivity of Na0.5Bi0.5TiO3 (NBT)-based materials has been investigated intensively in the past decade; however, the conduction behaviour with incorporation of variable-valence elements has been limited. Here (NBT)1−x(BiCoO3)x (NBT-BC, 0 ≤ x ≤ 0.06) solid solutions were prepared by a solid-state reaction and their electrical properties were investigated by impedance spectroscopy. The results show that incorporation of BC changes the bulk conduction mechanism from predominant oxide-ion conduction for NBT to mixed ionic–electronic conduction for NBT-BC solid solutions. The n-type electronic component is induced by loss of oxygen at high temperatures which reduces Co3+ to Co2+, and the ionic conduction is suppressed due to trapping of oxygen vacancies by Image ID:d3ta02709k-t1.gif (or Image ID:d3ta02709k-t2.gif). Bulk conductivity (σb) for single-phase compositions (0 ≤ x ≤ 0.04) shows a volcano-shape variation with increasing x due to a combined effect from the suppressed ionic contribution and the emergent electronic contribution. NBT-BC solid solutions represent a new Type II NBT with mixed conduction behavior but high σb and pave the way to understanding the electrical conduction mechanisms of NBT-based materials with the presence of variable-valence dopants, which may facilitate discovery of mixed conductors as electrode materials for solid oxide fuel cells.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © The Royal Society of Chemistry 2023 |
Keywords: | Engineering; Chemical Sciences; Physical Chemistry |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > School of Chemical, Materials and Biological Engineering |
Funding Information: | Funder Grant number ENGINEERING AND PHYSICAL SCIENCE RESEARCH COUNCIL EP/L027348/1 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 16 Jan 2025 15:53 |
Last Modified: | 12 Mar 2025 14:30 |
Status: | Published |
Publisher: | Royal Society of Chemistry (RSC) |
Refereed: | Yes |
Identification Number: | 10.1039/d3ta02709k |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:221153 |