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Ageing and Wield-Forced Deageing Behaviour of Hard PZT Ceramics
Published in D.A. Hall, C.E. Millar, Sensors and Actuators, 2020
Hard PZT (Lead Zirconate Titanate) ceramics are widely used in high power electromechanical transducers, for example in ultrasonic cleaners and SONAR transmitters.1 The stability of such materials under high drive conditions, with field levels typically in the range 400 to 800 V mm-1,2 is a direct result of ageing processes which act to restrict ferroelectric domain wall motion. In acceptor (e.g. Mn, Fe) doped perovskite ferroelectrics, the observed reductions in dielectric permittivity and loss during ageing are attributed to the presence of acceptor ion-oxygen vacancy defect associates.3,4 These dipolar defects gradually reorient towards the direction of the local domain polarisation, resulting in a reduction of domain wall mobility.5
Current Trends for Actuators and Micromechatronics
Published in Kenji Uchino, Micro Mechatronics, 2019
On the other hand, piezoelectric strain and electrostriction are induced by an electric field, and relatively large strains can be obtained in a variety of materials. Hence, piezoelectric and electrostrictive actuators are considered the most promising. Lead zirconate titanate (PZT)-based piezoelectric ceramics are most commonly used due to their availability, linear characteristics, low driving energy (low permittivity), and temperature stability at room temperature, as compared to electrostrictive devices. Electrostrictive actuators are preferred for applications where there may be significant temperature variations which may cause the “depoling” in a piezoelectric material (such as experienced by components used on the space shuttle) or high stress conditions (as occur for cutting machine devices). In terms of their reliability, electrostrictive materials are considered better than piezoelectrics in these cases, because they exhibit significantly less degradation and aging under severe conditions. However, the electrostrictor requires a high current power supply (due to a large capacitance) for high-speed applications.
Nanostructured Biointerfaces
Published in Šeila Selimovic, Nanopatterning and Nanoscale Devices for Biological Applications, 2017
Jean Paul Allain, Monica Echeverry-Rendón, Juan Jose Pavón, Sandra L. Arias
A SAW device mainly consists of a planar structure with electrodes on a piezoelectric material including interdigital transducers (IDTs) [81]. Of all the known piezoelectric materials, Pb-based piezoelectric materials, such as lead zirconate titanate (PZT), are widely used given their excellent piezoelectric properties. However, lead toxicity has motivated studies of materials without lead for environmentally friendly and biocompatible attributes. IDTs based on nonlead materials can consist of lead-free piezoelectric materials such as LiNbO3, ZnO, or compound III–V semiconductors. Unexplored materials that can usher in a new class of advanced sustainable materials for SAW devices may include surface-doped grapheme [82] and bioderived materials such as cellulose [83,84]. One of the most commonly used substrates that matches many of the required conditions for the proper generation of SAWs is lithium tantalate (LiTaO3) [81]. Applying a high-frequency (generally between 80 and 100 MHz) alternative voltage by means of the IDTs, acoustic waves are generated on the substrate, which, in turn, results in a specific resonance frequency that is characteristic of the acoustic wave speed propagation on such a substrate. This frequency is sensitive to measurable changes on the substrate surface, for instance, those produced by the interaction of the surface with specific biological materials.
Multi-perforated Energy-Efficient Piezoelectric Energy Harvester Using Improved Stress Distribution
Published in IETE Journal of Research, 2023
Ashutosh Anand, Srikanta Pal, Sudip Kundu
In this paper, ZnO is used as the PZ material for designing the PZEH. Lead Zirconate Titanate (PZT) has high piezoelectric coefficient (d31 = 741 pC/N) than most of the other known PZ materials. The presence of Lead in PZT makes it harmful to the environment and is not considered for this study. Some of the biocompatible piezoelectric materials such as ZnO [1,2], Aluminium nitride [1,2,17], and Barium Titanate (BaTiO3) [17] are compared along with PZT. The piezoelectric charge coefficient of the ZnO, AlN, and BaTiO3 is 11.34, 3.84, and 149 pC/N, respectively [1,2]. The relative permittivity’s of PZT, ZnO, AlN, and BaTiO3 are 3400, 12.64, 10.256, and 1200, respectively [1,2]. The ratio of PZ charge coefficient and relative permittivity gives the PZ voltage coefficient. The respective voltage coefficient of PZT, ZnO, AlN, and BaTiO3 as calculated are 0.217, 0.897, 0.374, and 0.124 Vm/N, respectively [1,2]. ZnO has been selected as the PZ materials as it has the maximum voltage coefficient among all the materials discussed here.
Enhanced electrical properties of new lead-free 0.995Bi0.5(Na0.80K0.20)0.5TiO3-0.005LiNbO3 ceramics by (Ba0.98Nd0.02)TiO3 doping
Published in Journal of Asian Ceramic Societies, 2021
Pimpilai Wannasut, Pharatree Jaita, Methee Promsawat, Anucha Watcharapasorn
Lead zirconate titanate (PZT) is a widely used perovskite material and about 60% of the commercially manufactured electronic products contain this compound. However, lead-based compounds are considered harmful for human body and surrounding environment due to the presence of lead and lead-oxide during the production process and usage of these devices [1,2]. The piezoelectric devices used in many applications still employ lead-based systems due to their outstanding piezoelectric properties [2]. Therefore, the search for lead-free piezoelectric ceramic systems, such as (Ba0.85Ca0.15Zr0.1T0.9)O3 (BCZT) [3], Bi0.5(Na0.80K0.20)0.5TiO3 (BNKT) [4], Ba0.5Na0.5TiO3 (BNT) [5] and BaTiO3 (BT) [6] and attempts to improve their properties have currently attracted much interest and effort.
Temperature dependence on ferroelectric properties and strain performance of PLZT ceramics containing 9 mol% La
Published in Phase Transitions, 2020
Narit Funsueb, Apichart Limpichaipanit, Athipong Ngamjarurojana
Piezoelectric effect involves with the development of surface charge in response to an applied pressure (direct effect) or the creation of mechanical displacement in response to an applied electric field (converse effect), which are useful for sensors and actuators, respectively. Perovskite lead-based materials have significant practical and academic importance because of their excellent dielectric, ferroelectric and piezoelectric properties. The examples solid-solution systems are (Pb,La)(Zr,Ti)O3, (Pb,Sr)(Zr,Ti)O3, (Pb,Ba)(Zr,Ti)O3, Pb(Zr,Ti,Sn)O3, (Pb,La)TiO3, and Pb(Mg,Nb)O3–PbZrO3–PbTiO3 [1–3]. Generally, lead-based ceramics especially lead zirconate titanate (PZT) ceramics are widely used in the application such as capacitors, sensors and actuators. PZT is the highly responsive material to the doping, which can be divided into the soft (donor doped) and hard (acceptor doped) groups as a reference to its ferroelectric properties depending on the mobility of the dipoles or domains for induced polarization and strain behavior [2, 4].