Wesley, C. orcid.org/0000-0001-6964-7265, Bellcase, L., Forrester, J.S. et al. (3 more authors) (2024) Solid state synthesis of BiFeO3 occurs through the intermediate Bi25FeO39 compound. Journal of the American Ceramic Society, 107 (6). pp. 3716-3723. ISSN 0002-7820
Abstract
The solid-state synthesis of perovskite BiFeO3 has been a topic of interest for decades. Many studies have reported challenges in the synthesis of BiFeO3 from starting oxides of Bi2O3 and Fe2O3, mainly associated with the development of persistent secondary phases such as Bi25FeO39 (sillenite) and Bi2Fe4O9 (mullite). These secondary phases are thought to be a consequence of unreacted Fe-rich and Bi-rich regions, that is, incomplete interdiffusion. In the present work, in situ high-temperature X-ray diffraction is used to demonstrate that Bi2O3 first reacts with Fe2O3 to form sillenite Bi25FeO39, which then reacts with the remaining Fe2O3 to form BiFeO3. Therefore, the synthesis of perovskite BiFeO3 is shown to occur via a two-step reaction sequence with Bi25FeO39 as an intermediate compound. Because Bi25FeO39 and the γ-Bi2O3 phase are isostructural, it is difficult to discriminate them solely from X-ray diffraction. Evidence is presented for the existence of the intermediate sillenite Bi25FeO39 using quenching experiments, comparisons between Bi2O3 behavior by itself and in the presence of Fe2O3, and crystal structure examination. With this new information, a proposed reaction pathway from the starting oxides to the product is presented.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2024 The Authors. Journal of the American Ceramic Society published by Wiley Periodicals LLC on behalf of American Ceramic Society. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited: https://creativecommons.org/licenses/by/4.0/ |
Keywords: | ferrites; ferroelectricity/ferroelectric materials; perovskites; synthesis; X-ray methods |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Materials Science and Engineering (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 09 Feb 2024 11:43 |
Last Modified: | 07 Nov 2024 11:46 |
Status: | Published |
Publisher: | Wiley |
Refereed: | Yes |
Identification Number: | 10.1111/jace.19702 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:208724 |