Structural and electrical properties of BKT rich Bi0.5K0.5TiO3-K0.5Na0.5NbO3 system
A new lead free (1−x) Bi0.5K0.5TiO3–(x) K0.5Na0.5NbO3 (BKT-KNN) system (0.0 ≤ x ≤ 0.15) with density of 94-97% is reported. Tetragonal structure of BKT-KNN is apparent for 0 ≤ x ≤ 0.06 with 1.02 ≤ (c/a) ≤ 1.012. Compositions with x ≥ 0.15 show orthorhombic structure (like KNN) and x = 0.08 & x =...
Main Authors: | , |
---|---|
Format: | Article |
Language: | English |
Published: |
AIP Publishing LLC
2013-03-01
|
Series: | AIP Advances |
Online Access: | http://link.aip.org/link/doi/10.1063/1.4796166 |
id |
doaj-5f7cf29153c44026bf0f4a7e83c5babc |
---|---|
record_format |
Article |
spelling |
doaj-5f7cf29153c44026bf0f4a7e83c5babc2020-11-24T21:19:20ZengAIP Publishing LLCAIP Advances2158-32262013-03-013303212903212910.1063/1.4796166Structural and electrical properties of BKT rich Bi0.5K0.5TiO3-K0.5Na0.5NbO3 systemAmrita SinghRatnamala ChatterjeeA new lead free (1−x) Bi0.5K0.5TiO3–(x) K0.5Na0.5NbO3 (BKT-KNN) system (0.0 ≤ x ≤ 0.15) with density of 94-97% is reported. Tetragonal structure of BKT-KNN is apparent for 0 ≤ x ≤ 0.06 with 1.02 ≤ (c/a) ≤ 1.012. Compositions with x ≥ 0.15 show orthorhombic structure (like KNN) and x = 0.08 & x = 0.10 are pseudocubic. Addition of KNN by a small amount (up to 4 mole %) is shown to improve piezoelectric properties, keeping the ferroelectric and dielectric values comparable to those of BKT. Optimized properties with d33 = 129 pC/N, kp = 29%, Pmax = 35 μC/cm2, Pr = 24 μC/cm2, ɛm = 4600, Tm = 370 °C and Td = 260 °C are observed for x = 0.03 sample. In the tetragonal range, a correlation between lattice distortion (c/a), piezoelectric coefficient (d33) and depolarization temperature Td is established. Decrease in c/a seems to result in easy poling by field and easy depoling by temperature, leading to an increase in d33 but a decrease in Td. A phase diagram for 1-xBKT-xKNN (0 ≤ x ≤ 0.10) is proposed. It is shown that addition of more than 6 mole % of KNN leads to the lowering of Td (where the structure becomes tetragonal to pseudocubic) considerably, resulting into a shift in tetragonal- pseudocubic phase boundary towards lower temperature.http://link.aip.org/link/doi/10.1063/1.4796166 |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Amrita Singh Ratnamala Chatterjee |
spellingShingle |
Amrita Singh Ratnamala Chatterjee Structural and electrical properties of BKT rich Bi0.5K0.5TiO3-K0.5Na0.5NbO3 system AIP Advances |
author_facet |
Amrita Singh Ratnamala Chatterjee |
author_sort |
Amrita Singh |
title |
Structural and electrical properties of BKT rich Bi0.5K0.5TiO3-K0.5Na0.5NbO3 system |
title_short |
Structural and electrical properties of BKT rich Bi0.5K0.5TiO3-K0.5Na0.5NbO3 system |
title_full |
Structural and electrical properties of BKT rich Bi0.5K0.5TiO3-K0.5Na0.5NbO3 system |
title_fullStr |
Structural and electrical properties of BKT rich Bi0.5K0.5TiO3-K0.5Na0.5NbO3 system |
title_full_unstemmed |
Structural and electrical properties of BKT rich Bi0.5K0.5TiO3-K0.5Na0.5NbO3 system |
title_sort |
structural and electrical properties of bkt rich bi0.5k0.5tio3-k0.5na0.5nbo3 system |
publisher |
AIP Publishing LLC |
series |
AIP Advances |
issn |
2158-3226 |
publishDate |
2013-03-01 |
description |
A new lead free (1−x) Bi0.5K0.5TiO3–(x) K0.5Na0.5NbO3 (BKT-KNN) system (0.0 ≤ x ≤ 0.15) with density of 94-97% is reported. Tetragonal structure of BKT-KNN is apparent for 0 ≤ x ≤ 0.06 with 1.02 ≤ (c/a) ≤ 1.012. Compositions with x ≥ 0.15 show orthorhombic structure (like KNN) and x = 0.08 & x = 0.10 are pseudocubic. Addition of KNN by a small amount (up to 4 mole %) is shown to improve piezoelectric properties, keeping the ferroelectric and dielectric values comparable to those of BKT. Optimized properties with d33 = 129 pC/N, kp = 29%, Pmax = 35 μC/cm2, Pr = 24 μC/cm2, ɛm = 4600, Tm = 370 °C and Td = 260 °C are observed for x = 0.03 sample. In the tetragonal range, a correlation between lattice distortion (c/a), piezoelectric coefficient (d33) and depolarization temperature Td is established. Decrease in c/a seems to result in easy poling by field and easy depoling by temperature, leading to an increase in d33 but a decrease in Td. A phase diagram for 1-xBKT-xKNN (0 ≤ x ≤ 0.10) is proposed. It is shown that addition of more than 6 mole % of KNN leads to the lowering of Td (where the structure becomes tetragonal to pseudocubic) considerably, resulting into a shift in tetragonal- pseudocubic phase boundary towards lower temperature. |
url |
http://link.aip.org/link/doi/10.1063/1.4796166 |
work_keys_str_mv |
AT amritasingh structuralandelectricalpropertiesofbktrichbi05k05tio3k05na05nbo3system AT ratnamalachatterjee structuralandelectricalpropertiesofbktrichbi05k05tio3k05na05nbo3system |
_version_ |
1726005909149188096 |