Dramatic influence of Dy{sup 3+} doping on strain and domain structure in lead-free piezoelectric 0.935(Na{sub 1/2}Bi{sub 1/2})TiO{sub 3}−0.065BaTiO{sub 3} ceramics

Journal Article · Tue Dec 15 00:00:00 EST 2015 · AIP Advances

DOI:https://doi.org/10.1063/1.4938514· OSTI ID:22492223

Li, C. Q.; Zhang, J. Z.; Chu, J. H. ^[1]; Yao, Q. R.; Wang, F. F.; Liu, A. Y.; Shi, W. Z. ^[2]

---

1. Department of Electronic Engineering, East China Normal University, Shanghai 200241 (China)
2. Department of Physics, Shanghai Normal University, Shanghai 200234 (China)

An electric-field induced giant strain response and doping level dependent domain structural variations have been studied in the dysprosium (Dy{sup 3+})-modified 0.935(Na{sub 1/2}Bi{sub 1/2})TiO{sub 3}-0.065BaTiO{sub 3}(xDy : NBBT) ceramics with the doping levels of 0%, 0.5%, 1%, and 2%. X-ray diffraction and Raman spectroscopy analyses not only demonstrates the change in ionic configurations induced by Dy{sup 3+} doping, but also shows the local crystal symmetry for x ≥ 0.5% doping levels to deviate from the idealized cubic structure. Piezoresponse force microscopy measurement exhibits the presence of an intermediate phase with orthorhombic symmetry at the critical Dy{sup 3+} doping level of 2%. Moreover, at this doping level, a giant recoverable nonlinear strain of ∼0.44% can be observed with high normalized strain (S{sub max}/E{sub max}) of 728 pm/V. At the same applied field, the strain exhibits a 175% increase than that of NBBT ceramic. Such a large strain stems from the varying coherence lengths of polar nanoregions (PNRs) and an unusual reversible 90° domain switching caused by the symmetry conforming property of point defects, where the restoring force is provided by unswitchable defects. The mechanism reveals a new possibility to achieve large electric-field strain effect for a wide range of ferroelectric systems, which can lead to applications in novel “on-off” actuators.

• OSTI ID: 22492223
• Journal Information: AIP Advances, Vol. 5, Issue 12; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACTUATORS
BARIUM COMPOUNDS
BISMUTH COMPOUNDS
CERAMICS
COHERENCE LENGTH
CRYSTALS
DOMAIN STRUCTURE
DYSPROSIUM IONS
ELECTRIC FIELDS
FERROELECTRIC MATERIALS
MICROSCOPY
ORTHORHOMBIC LATTICES
PIEZOELECTRICITY
POINT DEFECTS
RAMAN SPECTROSCOPY
SODIUM COMPOUNDS
STRAINS
TITANATES
TITANIUM OXIDES
X-RAY DIFFRACTION