Dynamics and grain orientation dependence of the electric field induced phase transformation in Sm modified BiFeO3 ceramics

Jeppe Ormstrup, Maja Makarovic, Marta Majkut, Tadej Rojac, Julian Walker, Hugh Simons*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Samarium-modified bismuth ferrite ((Bi,Sm)FeO3 or BSFO) is a room-temperature multiferroic with a morphotropic phase boundary near 15.5 mol% Sm, where ferroelectric, antiferroelectric and paraelectric phases coexist and the electromechanical response (Smax/Emax and d33) is maximized. Recently, an electric field induced phase transformation was discovered, which is believed to play a significant role in the macroscopic electromechanical response. Here, we used in situ synchrotron X-ray powder diffraction to directly measure this transformation in real time within bulk ceramics to determine the dynamics, structural pathway and crystallographic orientation dependence of the transformation. Our results show that there are two transformation pathways; an antiferroelectric-to-ferroelectric transformation, which is revesible, and a paraelectric-to-ferroelectric transformation, which is irreversible. Furthermore, these transformations occur with a strong orientation dependence with respect to the applied electric field direction, and with extremely slow dynamics - just 2 to 10 minutes - orders of magnitude longer than in other ferroelectrics (e.g. Bi1/2Na1/2TiO3-BaTiO3 or BNT-BT). These findings point to texturing and the elimination of the paraelectric phase to enhance the electromechanical response. Moreover, they provide a detailed picture of the transformation dynamics and a greater understanding of electric field induced transformations in ferroelectric ceramics.
Original languageEnglish
JournalJournal of Materials Chemistry C
Volume6
Issue number28
Pages (from-to)7635-7641
ISSN2050-7526
DOIs
Publication statusPublished - 2018

Cite this

@article{044bb840dbe743469621ed5cf3bc4ddd,
title = "Dynamics and grain orientation dependence of the electric field induced phase transformation in Sm modified BiFeO3 ceramics",
abstract = "Samarium-modified bismuth ferrite ((Bi,Sm)FeO3 or BSFO) is a room-temperature multiferroic with a morphotropic phase boundary near 15.5 mol{\%} Sm, where ferroelectric, antiferroelectric and paraelectric phases coexist and the electromechanical response (Smax/Emax and d33) is maximized. Recently, an electric field induced phase transformation was discovered, which is believed to play a significant role in the macroscopic electromechanical response. Here, we used in situ synchrotron X-ray powder diffraction to directly measure this transformation in real time within bulk ceramics to determine the dynamics, structural pathway and crystallographic orientation dependence of the transformation. Our results show that there are two transformation pathways; an antiferroelectric-to-ferroelectric transformation, which is revesible, and a paraelectric-to-ferroelectric transformation, which is irreversible. Furthermore, these transformations occur with a strong orientation dependence with respect to the applied electric field direction, and with extremely slow dynamics - just 2 to 10 minutes - orders of magnitude longer than in other ferroelectrics (e.g. Bi1/2Na1/2TiO3-BaTiO3 or BNT-BT). These findings point to texturing and the elimination of the paraelectric phase to enhance the electromechanical response. Moreover, they provide a detailed picture of the transformation dynamics and a greater understanding of electric field induced transformations in ferroelectric ceramics.",
author = "Jeppe Ormstrup and Maja Makarovic and Marta Majkut and Tadej Rojac and Julian Walker and Hugh Simons",
year = "2018",
doi = "10.1039/c8tc01951g",
language = "English",
volume = "6",
pages = "7635--7641",
journal = "Journal of Materials Chemistry C",
issn = "2050-7526",
publisher = "R S C Publications",
number = "28",

}

Dynamics and grain orientation dependence of the electric field induced phase transformation in Sm modified BiFeO3 ceramics. / Ormstrup, Jeppe; Makarovic, Maja; Majkut, Marta; Rojac, Tadej; Walker, Julian; Simons, Hugh.

In: Journal of Materials Chemistry C, Vol. 6, No. 28, 2018, p. 7635-7641.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Dynamics and grain orientation dependence of the electric field induced phase transformation in Sm modified BiFeO3 ceramics

AU - Ormstrup, Jeppe

AU - Makarovic, Maja

AU - Majkut, Marta

AU - Rojac, Tadej

AU - Walker, Julian

AU - Simons, Hugh

PY - 2018

Y1 - 2018

N2 - Samarium-modified bismuth ferrite ((Bi,Sm)FeO3 or BSFO) is a room-temperature multiferroic with a morphotropic phase boundary near 15.5 mol% Sm, where ferroelectric, antiferroelectric and paraelectric phases coexist and the electromechanical response (Smax/Emax and d33) is maximized. Recently, an electric field induced phase transformation was discovered, which is believed to play a significant role in the macroscopic electromechanical response. Here, we used in situ synchrotron X-ray powder diffraction to directly measure this transformation in real time within bulk ceramics to determine the dynamics, structural pathway and crystallographic orientation dependence of the transformation. Our results show that there are two transformation pathways; an antiferroelectric-to-ferroelectric transformation, which is revesible, and a paraelectric-to-ferroelectric transformation, which is irreversible. Furthermore, these transformations occur with a strong orientation dependence with respect to the applied electric field direction, and with extremely slow dynamics - just 2 to 10 minutes - orders of magnitude longer than in other ferroelectrics (e.g. Bi1/2Na1/2TiO3-BaTiO3 or BNT-BT). These findings point to texturing and the elimination of the paraelectric phase to enhance the electromechanical response. Moreover, they provide a detailed picture of the transformation dynamics and a greater understanding of electric field induced transformations in ferroelectric ceramics.

AB - Samarium-modified bismuth ferrite ((Bi,Sm)FeO3 or BSFO) is a room-temperature multiferroic with a morphotropic phase boundary near 15.5 mol% Sm, where ferroelectric, antiferroelectric and paraelectric phases coexist and the electromechanical response (Smax/Emax and d33) is maximized. Recently, an electric field induced phase transformation was discovered, which is believed to play a significant role in the macroscopic electromechanical response. Here, we used in situ synchrotron X-ray powder diffraction to directly measure this transformation in real time within bulk ceramics to determine the dynamics, structural pathway and crystallographic orientation dependence of the transformation. Our results show that there are two transformation pathways; an antiferroelectric-to-ferroelectric transformation, which is revesible, and a paraelectric-to-ferroelectric transformation, which is irreversible. Furthermore, these transformations occur with a strong orientation dependence with respect to the applied electric field direction, and with extremely slow dynamics - just 2 to 10 minutes - orders of magnitude longer than in other ferroelectrics (e.g. Bi1/2Na1/2TiO3-BaTiO3 or BNT-BT). These findings point to texturing and the elimination of the paraelectric phase to enhance the electromechanical response. Moreover, they provide a detailed picture of the transformation dynamics and a greater understanding of electric field induced transformations in ferroelectric ceramics.

U2 - 10.1039/c8tc01951g

DO - 10.1039/c8tc01951g

M3 - Journal article

VL - 6

SP - 7635

EP - 7641

JO - Journal of Materials Chemistry C

JF - Journal of Materials Chemistry C

SN - 2050-7526

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ER -