Article The Conversion Polymorphism of Perovskite Phases in the BiCrO3–BiFeO3 System

Alexei A. Belik SAMURAI ORCID (National Institute for Materials Science)

Collection

Citation
Alexei A. Belik. The Conversion Polymorphism of Perovskite Phases in the BiCrO3–BiFeO3 System. Inorganics. 2025, 13 (3), 91. https://doi.org/10.3390/inorganics13030091

Description:

(abstract)

Perovskite-type materials containing Bi3+ cations at the A sites are interesting from viewpoints of applications and fundamental science as the lone pair of Bi3+ cations often stabilizes polar, ferro-electric structures. It can be illustrated by a lot of discoveries of different new functionalities in bulk and thin films of BiFeO3 and its derivatives. In this work, we investigated solid solutions of BiCr1-xFexO3 with 0.1 < x < 0.4 prepared by a high-pressure (HP) method and post-synthesis an-nealing at ambient pressure (AP). HP-BiCr1-xFexO3 modifications with 0.1 < x < 0.3 were mixtures of two phases with space groups C2/c and Pbam, and the amount of the C2/c phase decreased with increasing x. The amount of the C2/c phase was also significantly decreased in AP-BiCr1-xFexO3 modifications, and the C2/c phase almost disappeared in AP-BiCr1-xFexO3 with 0.2 < x < 0.3. Fun-damental, strong reflections of HP-BiCr1-xFexO3 and AP-BiCr1-xFexO3 were almost unchanged; on the other hand, weak superstructure reflections were different and showed clear signs of strong anisotropic broadening and incommensurate positions. These structural features prevented us from determining their room-temperature structures. On the other hand, HP-BiCr1-xFexO3 and AP-BiCr1-xFexO3 showed high-temperature structural phase transitions to the GdFeO3-type Pnma modification at Tsrt = 450 K (x = 0.1), Tsrt = 480 K (x = 0.2), Tsrt = 510 K (x = 0.3), and Tsrt = 546 K (x = 0.4). Crystal structures of the GdFeO3-type Pnma modifications of all the samples were investigated by synchrotron powder X-ray diffraction. Magnetic properties of HP-BiCr1-xFexO3 and AP-BiCr1-xFexO3 were quite close to each other (HP vs AP), and the x = 0.2 samples demonstrated negative magnetization phenomena without signs of the exchange bias effect.

Rights:

Keyword: multiferroics, doped BiFeO3, BiCrO3, high-pressure synthesis, irreversible transformations, conversion polymorphism, incommensurate structures

Date published: 2025-03-18

Publisher: MDPI AG

Journal:

  • Inorganics (ISSN: 23046740) vol. 13 issue. 3 91

Funding:

Manuscript type: Publisher's version (Version of record)

MDR DOI:

First published URL: https://doi.org/10.3390/inorganics13030091

Related item:

Other identifier(s):

Contact agent:

Updated at: 2025-11-08 08:30:07 +0900

Published on MDR: 2025-11-08 08:21:17 +0900

Filename Size
Filename Inorganics-V13-91-BiCrO3-BiFeO3.pdf (Thumbnail)
application/pdf
Size 4.26 MB Detail