Role of coexisting tetragonal regions in the rhombohedral phase of Na0.5Bi0.5TiO3-xat.%BaTiO3 crystals on enhanced piezoelectric properties on approaching the morphotropic phase boundary

ABSTRACTBiFeO3-PbTiO3 (BF-PT) crystalline solutions have been modified by La3+, Ga3+ and Ba2+ substituent. The modified BF-PT had morphotropic phase boundary (MPB), at which the ferroelectric rhombohedral phase transferred to the tetragonal symmetry. The piezoelectric properties at the MPB were strongly depended on different substituents. The modified BF-PT system showed the insulation resistivity up to 1012 ω·cm at room temperature. Lanthanum played a critical role making BF-PT softer to be poled to the piezoelectric state. Ga provided BF-PT additional polarization and breakdown strength with La substituent. In the system with La3+, Ga3+ and Ba3+ simultaneously, addition of Ba enhanced dielectric and piezoelectric activity. It was flexible to tailor BF-PT by using different substituents. In the vicinity of MPB, the Curie temperature Tc was above 385°C of BF-PT for La <10 at%, whereas the d33 constant was as high as 295 pC/N for one with La of 20 at%. The modified BF-PT revealed comparable performances to conventional Pb(Zr,Ti)O3 (PZT) ceramics, but in significantly lead reduced forms.

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Morphotropic Phase Boundary Study of the BNT-BKT Lead-Free Piezoelectric Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1908 ◽

2008 ◽

Vol 368-372 ◽

pp. 1908-1910 ◽

Cited By ~ 53

Author(s):

Wei Zhao ◽

He Ping Zhou ◽

Yong Ke Yan ◽

Dan Liu

Keyword(s):

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Composition Range ◽

Piezoelectric Properties ◽

Rhombohedral Phase ◽

Sodium Titanate ◽

Xrd Analysis ◽

Lead Free ◽

Bismuth Sodium Titanate ◽

Potassium Titanate

A lead-free piezoelectric ceramic binary system based on bismuth sodium titanate (Bi0.5Na0.5)TiO3 (BNT)-bismuth potassium titanate (Bi0.5K0.5)TiO3 (BKT) was synthesized by conventional mixed-oxide technique. The XRD analysis showed that the rhombohedral-tetragonal morphotropic phase boundary (MPB) of the Bi0.5 (Na1-xKx)0.5 TiO3 system was in the composition range of x = 0.16 ~ 0.20. In addition, the piezoelectric properties of this system were also investigated. It was indicated that the piezoelectric properties are better with the compositions near the rhombohedral phase within the MPB than the compositions near the tetragonal phase.

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Accelerated search for BaTiO3-based piezoelectrics with vertical morphotropic phase boundary using Bayesian learning

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1607412113 ◽

2016 ◽

Vol 113 (47) ◽

pp. 13301-13306 ◽

Cited By ~ 52

Author(s):

Dezhen Xue ◽

Prasanna V. Balachandran ◽

Ruihao Yuan ◽

Tao Hu ◽

Xiaoning Qian ◽

...

Keyword(s):

Solid Solution ◽

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Bayesian Approach ◽

Bayesian Learning ◽

Piezoelectric Properties ◽

Training Data ◽

Materials Informatics ◽

Initial Training ◽

New Materials

An outstanding challenge in the nascent field of materials informatics is to incorporate materials knowledge in a robust Bayesian approach to guide the discovery of new materials. Utilizing inputs from known phase diagrams, features or material descriptors that are known to affect the ferroelectric response, and Landau–Devonshire theory, we demonstrate our approach for BaTiO3-based piezoelectrics with the desired target of a vertical morphotropic phase boundary. We predict, synthesize, and characterize a solid solution, (Ba0.5Ca0.5)TiO3-Ba(Ti0.7Zr0.3)O3, with piezoelectric properties that show better temperature reliability than other BaTiO3-based piezoelectrics in our initial training data.

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Enhanced piezoelectric properties of (1 − x)BiFe0.98(Zn0.5Hf0.5)0.02O3-xBaTiO3 ceramics near the morphotropic phase boundary

Dalton Transactions ◽

10.1039/c9dt04664j ◽

2020 ◽

Vol 49 (17) ◽

pp. 5573-5580 ◽

Cited By ~ 1

Author(s):

Yunjing Shi ◽

Hairui Bai ◽

Fei Yan ◽

Rui Hu ◽

Kaikai Chen ◽

...

Keyword(s):

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Piezoelectric Coefficient ◽

Piezoelectric Properties ◽

Phase Coexistence ◽

T Phase

The component with the R–T phase coexistence near MPB affords an optimal piezoelectric coefficient (d33) of 130 pC N−1.

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Structure and dielectric/piezoelectric properties of LiNbO3-doped BiScO3–PbTiO3 ceramics with morphotropic phase boundary composition

Journal of Materials Science ◽

10.1007/s10853-011-5842-8 ◽

2011 ◽

Vol 47 (2) ◽

pp. 696-701 ◽

Cited By ~ 3

Author(s):

Qiang Zhang ◽

Zhenrong Li ◽

Na Zhang ◽

Zhuo Xu

Keyword(s):

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Piezoelectric Properties ◽

Morphotropic Phase Boundary Composition ◽

Boundary Composition ◽

Phase Boundary Composition ◽

Pbtio3 Ceramics

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Microstructure and electrical properties of 0.5PZN-0.5PZT relaxor ferroelectrics close to the morphotropic phase boundary

Journal of Materials Research ◽

10.1557/jmr.2009.0246 ◽

2009 ◽

Vol 24 (6) ◽

pp. 2029-2034 ◽

Cited By ~ 13

Author(s):

Lu-Yang Zhao ◽

Yu-Dong Hou ◽

Li-Min Chang ◽

Man-Kang Zhu ◽

Hui Yan

Keyword(s):

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Oxygen Vacancies ◽

Rhombohedral Phase ◽

Relaxor Ferroelectrics ◽

Arrhenius Law ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Mixing Method

Relaxor ferroelectrics of Pb(Zn1/3Nb2/3)0.5(Zr0.47Ti0.53)0.5O3 (0.5PZN-0.5PZT) were prepared using the conventional oxide mixing method. Both x-ray diffraction analysis and Raman spectroscopy indicate that the amounts of rhombohedral phase are close to tetragonal phase, implying the presence of the morphotropic phase boundary (MPB) in the system of 0.5PZN-0.5PZT, and this result was further confirmed by transmission electron microscopy (TEM) micrographs. At MPB composition, the excellent piezoelectric properties, such as kp (0.66) and d33 (425pC/N), were obtained due to the more possible polarization directions of domains and high dc resistivity of 6.5 × 1010 Ω·cm. Meanwhile, the dielectric studies revealed that the indicator of the degree of diffuseness γ value is 1.73, implying that the relaxor nature of the 0.5PZN-0.5PZT is ceramic. The activation energy related to the dc conductivity was estimated from a linear fitting of the Arrhenius law. The value of 0.09 and 1.04 eV for low and high temperature range corresponds well to the activation energies of migration and first ionization of the oxygen vacancies.

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