Extrinsic response enhancement at the polymorphic phase boundary in piezoelectric materials

Morphotropic phase boundary (MPB) containing piezoelectric systems generally exhibit enhanced piezoelectric performance at compositions within, or close to, the MPB region. The mechanism/s underlying such enhancement, however, are still contentious due to complex micro/nanostructure and apparently inherent local structural variability associated with octahedral tilt disorder/platelet precipitates in such piezoelectric materials. This paper reviews some recent structural analysis results from Bi0.5Na0.5TiO3 (BNT) and other binary, lead-free, piezoelectric materials systems derived from it via electron diffraction and in situ neutron diffraction. The results suggest that intrinsically existing local microstructure (LMS) in BNT essentially continues across the MPB region. The LMS, originating from inherent octahedral tilt disorder, is strongly temperature-, electric field-, pressure- and chemical composition-dependent, and may help to explain a series of phenomena observed in BNT-based binary materials systems, including the enhanced piezoelectric effect in the region of the MPB.

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Local-scale structures across the morphotropic phase boundary in PbZr1−x Ti x O3

IUCrJ ◽

10.1107/s2052252517016633 ◽

2018 ◽

Vol 5 (1) ◽

pp. 73-81 ◽

Cited By ~ 9

Author(s):

Nan Zhang ◽

Hiroko Yokota ◽

A. M. Glazer ◽

D. A. Keen ◽

Semën Gorfman ◽

...

Keyword(s):

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Lead Zirconate Titanate ◽

Piezoelectric Materials ◽

Function Analysis ◽

Sudden Change ◽

Functional Materials ◽

Lead Zirconate ◽

Coupling Factor ◽

Structure Property

Lead zirconate titanate (PZT) is one of the most widely studied piezoelectric materials, mainly because of its `mysterious' relationship between the so-called morphotropic phase boundary (MPB) and its strong piezoelectric coupling factor. Using results from a pair distribution function analysis, this paper examines how the complex local structure in PZT affects the long-range average structure across the MPB. A monoclinic M C type structure is discovered in PZT. A first-order transformation between the monoclinic M A and M C components in both the average and local structures explains the sudden change in piezoelectric effect around these compositions. The role of polarization rotation in the enhancement of the piezoelectric properties is discussed with respect to the composition of PZT. The structure–property relationship that is revealed by this study explains the unique properties of PZT, and may be applicable in the design of new MPB-type functional materials.

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WHAT CAN BE EXPECTED FROM LEAD-FREE PIEZOELECTRIC MATERIALS?

Functional Materials Letters ◽

10.1142/s1793604710000919 ◽

2010 ◽

Vol 03 (01) ◽

pp. 5-13 ◽

Cited By ~ 231

Author(s):

DRAGAN DAMJANOVIC ◽

NAAMA KLEIN ◽

JIN LI ◽

VIKTOR POROKHONSKYY

Keyword(s):

Domain Wall ◽

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Wall Motion ◽

Electromechanical Coupling ◽

Piezoelectric Properties ◽

Piezoelectric Materials ◽

Domain Wall Motion ◽

Lead Free

The reasons for the lower piezoelectric properties in the most studied lead-free piezoelectrics, modified (K, Na)NbO 3 and ( Bi 0.5 Na 0.5) TiO 3, are discussed. Contributions from domain wall motion and properties at the morphotropic phase boundary are considered and are compared to those in PZT. Lead-free, non-piezoelectric solutions to electromechanical coupling are discussed.

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Morphotropic Phase Boundary of Lead-Free Piezoelectric Ceramics from BNT- KN System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.55-57.225 ◽

2008 ◽

Vol 55-57 ◽

pp. 225-228 ◽

Cited By ~ 11

Author(s):

N. Pisitpipathsin ◽

W. Koontasing ◽

Sukum Eitssayeam ◽

Uraiwan Intatha ◽

Gobwute Rujijanagul ◽

...

Keyword(s):

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Niobium Oxide ◽

Perovskite Phase ◽

Piezoelectric Materials ◽

Research Work ◽

Lead Free ◽

Ceramic System ◽

Dielectric Data ◽

Ferroelectric Perovskite

In this research work, the investigation of the morphotropic phase boundary, physical properties and electrical properties of lead- free piezoelectric materials of bismuth sodium titanium oxide: (Bi0.5Na0.5)TiO3 (BNT) and potassium niobium oxide : KNbO3 (KN) in the ceramic system of (1-x)BNT- xKN where x= 0.00, 0.03, 0.05, 0.08, 0.10 and 0.15 by modified mixed oxide method was carried out. The BNT and KN powders were prepared separately using calcination technique with optimum calcination temperature for producing both BNT and KN powders of about 800°C. XRD results revealed that the BNT-KN ceramics with low KN content of x less than 0.05 contain ferroelectric perovskite phase with rhombohedral symmetries while the higher KN content ceramics have mixed symmetries between rhombohedral and orthorhombic. From the evidences including phases, microstructures and dielectric data of the BNT-KN ceramics, it may be assumed that the morphotropic phase boundary may be at around the composition of x = 0.05.

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Mechanical and Dielectrical Energy Dissipation Phenomena Study in Lead Zirconate Titanate Piezoelectric Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.895.274 ◽

2014 ◽

Vol 895 ◽

pp. 274-279

Author(s):

Abderrazak Bouzid ◽

Gilbert Fantozzi

Keyword(s):

Energy Dissipation ◽

Internal Friction ◽

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Lead Zirconate Titanate ◽

Dielectric Spectroscopy ◽

Piezoelectric Materials ◽

Lead Zirconate ◽

Low Frequencies ◽

Zirconate Titanate

The aim of the present work is to show the analogy between mechanical and dielectric dissipation phenomena occurring in the PZT near the morphotropic phase boundary MPB-. Mechanical dissipations are investigated by internal friction mechanical losses and associated modulus-as function of temperature at medium and low frequencies. Dielectric dissipations are investigated by dielectric spectroscopy at medium frequencies.

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Analysis of Sputtered Zinc Oxide Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001781 ◽

1980 ◽

Vol 38 ◽

pp. 416-417

Author(s):

T. A. Emma ◽

M. P. Singh

Keyword(s):

Electron Microscopy ◽

Zinc Oxide ◽

Piezoelectric Materials ◽

Oxide Films ◽

Optical Quality ◽

Zno Films ◽

Rf Power ◽

X Ray Diffraction ◽

Sputtered Films ◽

Zinc Oxide Films

Optical quality zinc oxide films have been characterized using reflection electron diffraction (RED), replication electron microscopy (REM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Significant microstructural differences were observed between rf sputtered films and planar magnetron rf sputtered films. Piezoelectric materials have been attractive for applications to integrated optics since they provide an active medium for signal processing. Among the desirable physical characteristics of sputtered ZnO films used for this and related applications are a highly preferred crystallographic texture and relatively smooth surfaces. It has been found that these characteristics are very sensitive to the type and condition of the substrate and to the several sputtering parameters: target, rf power, gas composition and substrate temperature.

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