Zirconate Titanate Research Articles

EVA/PZT‐Composite‐Based Triboelectric Nanogenerator for Energy Harvesting

The development of triboelectric nanogenerators (TENGs) has experienced rapid advancement in the past decade. In the present study, ethylene vinyl acetate (EVA) polymer and lead zirconium titanate (PZT) are taken as the host materials. The EVA–PZT elastomer composites are fabricated using different weight percentages (2.5%, 5.0%, 7.5%, and 10.0%) of PZT in EVA by solvent casting. The X‐ray diffraction investigation of these films reveals the presence of the PZT material and the formation of composites. TENGs have the potential to revolutionize energy harvesting and provide a sustainable energy source for a variety of applications. The electrical output performance of the single‐electrode‐mode‐based TENG is examined. The maximum output of 60 V and 165 nA is produced by the EVA–PZT 7.5 wt%/Al‐based TENG device. Further, TENG is used to power devices and gather biomechanical energy.

Effect of Eu3+ doping on structural and optical properties of zirconium titanate

The Europium activated (1–9 mol %) Zirconium Titanate nanoparticles (NPs) have been synthesized by the green solution combustion method using Aloe Vera gel extract as a reducing agent, followed by the calcination at 720 °C for 3hrs. All the synthesized samples crystallize in a pure orthorhombic crystal structure with the space group of Pbcn. The surface and bulk morphology were analyzed. The crystallite size increases, whereas the direct energy band gap was found to decrease with an increase in dopant concentration. Further, the effect of dopant concentration on the photoluminescence properties was studied. The presence of Eu3+ ion in the trivalent state in the host lattice was confirmed by its characteristic emission at 610 nm due to 5D0→7F2 (λex = 464 nm). The CIE coordinates were found in the red region of the CIE 1931 diagram. The CCT coordinates lie in the range 6288–7125 K. The Judd-Ofelt parameters and derived quantities were analyzed. This theory confirms the high symmetry of Eu3+ ions in the host lattice. These findings imply that ZTO:Eu3+ can be employed as a nanopowder material in a red-emitting phosphor material.

Structural and dielectric investigation of thermal treated TiO2/ZrO2 composite thin films grown by chemical beam vapor deposition

TiO2/ZrO2 (TZ) composite binary oxides thin films were synthesized by Chemical Beam Vapor Deposition technique with a combinatorial approach, followed by annealed at 600 °C for 1 h. Three different element compositions were used in the composite films, with TiO2/ZrO2 ratio of ∼80/20, ∼70/30 and ∼60/40 at.%. X-ray diffraction analysis indicated that the Zirconium titanate crystalline phase was predominated in the TZ composite films, particularly those with higher concentration of ZrO2. The TZ film with ∼60/40 at.% exhibited a maximum dielectric constant of ∼35, a loss tangent of ∼3 and a low leakage current density of ∼1.7 × 10−9A/cm2. These results suggest that the synergistic combination of TiO2 and ZrO2 makes them a potential candidate for capacitor applications.

Visible-Light-Induced Photodegradation of Methylene Blue Using Mn,N-codoped ZrTiO<sub>4</sub> as Photocatalyst

Composites of manganese and nitrogen-codoped zirconium titanate (Mn,N-codoped ZrTiO4) had been synthesized by the sol-gel method as a visible-light responsive photocatalyst for the photodegradation of methylene blue (MB). Synthesis was conducted at 25 °C using titanium(IV) isopropoxide, zirconium oxide, urea, and manganese(II) chloride. Mn,N-codoped ZrTiO4 containing fixed 10% nitrogen dopant (wN/wTi) with various Mn dopant contents (2, 4, 6, 8, and 10% wMn/wTi) and calcination temperatures (500, 700, and 900 °C) had been investigated. All of the Mn,N-codoped ZrTiO4 exhibit a band gap within the visible range (2.51 to 2.74 eV). Photodegradation of MB was performed under visible light illumination for 120 min. The highest activity was achieved up to 7.7 µg L−1 min−1, which was obtained from Mn,N-codoped ZrTiO4 calcined at 500 °C containing 6% Mn and 10% N dopants.

CHARACTERIZATION OF ENERGY BAND GAP THIN FILM BaTiO3 – BaZr0.5Ti0.5O3 USING DIFUSION REFLECTANCE SPECTROSCOPY (DRS) METHOD

Ferroelectric material is a dielectric material that has a high dielectric constant value so that it can be made in the form of thin films. Its application is based on electro-optical properties, one of which is the infrared thermal switch. This paper aims to determine the bandgap energy (Eg) of a 0.3BaTiO3 – 0.7BaZr0.5Ti0.5O3 thin film. The 0.3BaTiO3 – 0.7BaZr0.5Ti0.5O3 thin film is a semiconductor material with the valence band and conduction band separated by an energy bandgap (Eg). Thin films of 0.3BaTiO3 – 0.7BaZr0.5Ti0.5O3 were grown on FTO substrates using the sol-gel method. The films of 0.3BaTiO3 – 0.7BaZr0.5Ti0.5O3 were annealed at different temperatures of 700°C, 750°C and 800°C within 1 hour. Characterization was carried out using Ultra Violet Visible (UV-Vis) spectroscopy to determine Eg using the Diffusion Reflectance Spectroscopy (DRS) method. The DRS method was found to be better for solid materials considering the scattering component. The UV-Vis characterization results show that an increase in annealing temperature causes a decrease in Eg. For example the values ​​at 700°C, 750°C and 800°C are 3.5 ± 0.01 eV; 3.3±0.01 eV and 3.2±0.01 eV. The decrease in Eg is related to the diffusion of Barium Titanate (BaTiO3) ions into the Barium Zirconium Titanate (BZT) lattice forming a new sub-gap which in turn gives BT-BZT the ability to absorb lower light. Lower light absorption means more capable optics for multilayer systems.

Piezoelectricity and Thermophysical Properties of Ba0.90Ca0.10Ti0.96Zr0.04O3 Ceramics Modified with Amphoteric Nd3+ and Y3+ Dopants

Lead-free barium calcium titanate zirconate (BCTZ) ceramics doped with a single rare-earth element generally exhibit excellent piezoelectric properties. However, their electrical properties deteriorate at an excessive dopant content, limiting their application. In this study, amphoteric neodymium (Nd3+) and yttrium (Y3+)-codoped BCTZ-NYx ceramics were synthesized via a solid-state reaction at 1240 °C. The influences of the Y3+ content (x) on the structural features, electrical properties, mechanical properties, and thermophysical properties were investigated. At a small x (<0.18 mol%), Y3+ could enhance the fracture strength and electrical properties by eliminating oxygen vacancies, defect dipoles, and/or structural defects. However, the outstanding performance deteriorated with excessive x. Additionally, the mechanism of the defect chemistry at different x was deduced. At an yttrium content of 0.18 mol%, the ceramic exhibited high piezoelectricity and ferroelectricity with low domain-switching activation energy (Ea = 0.401 eV), indicating that it could replace commercial lead-based piezoelectric ceramics.

Acoustic Performance of Stress Gradient-Induced Deflection of Triangular Unimorphic/Bimorphic Cantilevers for MEMS Applications

This paper reports two piezoelectric materials of lead zirconium titanate (PZT) and aluminum nitride (AlN) used to simulate microelectromechanical system (MEMS) speakers, which inevitably suffered deflections as induced via the stress gradient during the fabrication processes. The main issue is the vibrated deflection from the diaphragm that influences the sound pressure level (SPL) of MEMS speakers. To comprehend the correlation between the geometry of the diaphragm and vibration deflection in cantilevers with the same condition of activated voltage and frequency, we compared four types of geometries of cantilevers including square, hexagon, octagon, and decagon in triangular membranes with unimorphic and bimorphic composition by utilizing finite element method (FEM) for physical and structural analyses. The size of different geometric speakers did not exceed 10.39 mm2; the simulation results reveal that under the same condition of activated voltage, the associated acoustic performance, such as SPL for AlN, is in good comparison with the simulation results of the published literature. These FEM simulation results of different types of cantilever geometries provide a methodology design toward practical applications of piezoelectric MEMS speakers in the acoustic performance of stress gradient-induced deflection in triangular bimorphic membranes.

Optimization of sintering temperature for dielectric studies of La doped BZT ceramics

In this work, we have reported optimization of sintering temperature for dielectric studies of Lanthanum (La3+) doped BZT ceramics. The sample Ba0.99La0.01Zr0.10Ti0.90O3 has been prepared by conventional solid-state reaction route with calcination at 1000 °C and 1100 °C. Samples calcined at both the temperatures have been sintered at three different temperatures 1125 °C, 1225 °C and 1325 °C. The as-synthesized samples have been characterized by X-ray diffraction for structural studies and scanning electron microscopy to confirm the surface morphology. XRD patterns of Ba0.99La0.01Zr0.10Ti0.90O3 calcined at 1100 °C show single crystalline phase with no impurity at 1325 °C. It has been observed that sintering temperature strongly influences the crystal structure and the dielectric properties of the prepared ceramic samples. The sharp and intense peaks in the XRD pattern of sample calcinated at 1100 °C and sintered at 1325 °C represents the formation of single-phase cubic perovskite structure. This indicates the incorporation of La3+ ions into the lattice of barium zirconium titanate. High dielectric constant has been observed at low frequency. Phase structure, variation of dielectric constant, loss and a.c conductivity with frequency at room temperature of Ba0.99La0.01Zr0.10Ti0.90O3 ceramic sample have been investigated in this paper.

Quantitative phase analysis of PZT and Lead tantalate composite by Rietveld technique

Quantitative phase analysis of Lead Zirconium Titanate (PbZr0.6Ti0.4O3 = PZT) and Lead Tantalate (Pb1.5Ta2O6.5 = PT) composite is reported. PZT and PT are synthesized following co-precipitation and semi-co-precipitation techniques simultaneously. Five different compositions of (1-x)PZT + xPT with different × mole percentages are synthesized. The calcined powders were compacted into pellets of 1 cm diameter. These pellets were annealed at 1000 °C for 2 h and followed by grinded to a fine powder for carrying X-ray diffraction measurements. All XRD patterns have a well isolated clear set of patterns which belongs to the PZT and PT phases. Refinement of the XRD data was carried out by the Rietveld technique using X-pert high score plus and the quantification of PZT and PT phases are reported.

Copper-and-Nitrogen-Codoped Zirconium Titanate (Cu-N-ZrTiO&lt;sub&gt;4&lt;/sub&gt;) as a Photocatalyst for Photo-Degradation of Methylene Blue under Visible-Light Irradiation

Synthesis and characterization of copper-and-nitrogen-codoped zirconium titanate (Cu-N-ZrTiO4) as a photocatalyst for the degradation of methylene blue (MB) have been conducted. The main purpose of this research was to investigate the co-doping effect of copper and nitrogen dopants in ZrTiO4 as a photocatalyst for the photodegradation of MB. Titanium-(IV) tetraisopropoxide (TTIP) was dissolved into ethanol and mixed with aqueous zirconia (ZrO2) suspension containing 10% nitrogen (N) (w/w to Ti) from urea and various amount of copper as dopants. The calcination was performed at temperatures of 500, 700, and 900 °C. The composites were characterized using Fourier transform infrared spectrophotometer (FTIR), X-ray diffractometer (XRD), scanning electron microscopy with energy dispersive X-ray (SEM-EDX) mapping, and specular reflectance UV-Visible spectrophotometer (SRUV-Vis). The degradation of 4 mg L−1 MB solution was conducted for various irradiation times. Characterization shows a significant decrease of the ZrTiO4 band gap from 3.09 to 2.65 eV, which was given by the composite with the addition of 4% Cu and calcination of 900 °C. Cu-N-ZrTiO4 composite can degrade MB solution up to 83% after 120 min under the irradiation of visible light.

Electric field-dependent phonon spectrum and heat conduction in ferroelectrics.

This article shows experimentally that an external electric field affects the velocity of the longitudinal acoustic phonons (vLA), thermal conductivity (κ), and diffusivity (D) in a bulk lead zirconium titanate-based ferroelectric. Phonon conduction dominates κ, and the observations are due to changes in the phonon dispersion, not in the phonon scattering. This gives insight into the nature of the thermal fluctuations in ferroelectrics, namely, phonons labeled ferrons that carry heat and polarization. It also opens the way for phonon-based electrically driven all-solid-state heat switches, an enabling technology for solid-state heat engines. A quantitative theoretical model combining piezoelectric strain and phonon anharmonicity explains the field dependence of vLA, κ, and D without any adjustable parameters, thus connecting thermodynamic equilibrium properties with transport properties. The effect is four times larger than previously reported effects, which were ascribed to field-dependent scattering of phonons.

A Precise Rotary Piezoelectric Actuator Based on the Spatial Screw Compliant Mechanism

Rotary piezoelectric actuators (RPAs) are widely used in various precise applications. But given the rotary axis offset caused by the single off-center driving force or the discrepancy of multiple piezoelectric elements, most previous works present rotary roundness loss. Besides, there is a contradiction between the motion range of RPA and its response speed. For solving these problems, an RPA based on the spatial screw compliant mechanism (SSCM) is hereby proposed; a theoretical model and an finite element (FE) model are built to verify the actuation principle and guide the structural design; and a prototype is fabricated and tested. The experimental results indicate that the static rotary angle changes from 0 to 4.935 mrad as the voltage changes from 0 to 100 V with a high resolution of 45.53 nrad. The first resonant and –3 dB cutoff frequencies are measured as 1361.5 and 2040.1 Hz, respectively. With the application of the SSCM, the RPA is proven capable of avoiding the rotary roundness loss in theory, and it can balance the milliradian-level rotary range with millisecond-level response speed driving by one lead zirconium titanate (PZT) stack under a small size of Φ32 × 68 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .

A phase-field model for electro-mechanical fracture with an open-source implementation of it using Gridap in Julia

In this paper, we propose a phase-field model for electro-mechanical fracture in brittle materials and provide an open-source implementation of the proposed model using a newly developed finite element (FE) toolbox, Gridap in Julia. Here, we have considered electric potential as an additional kinematic descriptor along with the displacement and phase-field variable. Using the virtual power principle, we have derived force balances for the electro-mechanical forces and a force balance associated with the damage. To incorporate the strong electro-mechanical coupling effect into the model, we have considered the Helmholtz free energy as a function of the electric field vector, strain tensor, phase-field variable, and the gradient of the phase-field variable. The proposed model ensures that the constitutive relations of the thermodynamic fluxes are on the satisfaction of the thermodynamic laws and can readily accommodate dissipative energy effects whenever needed. The proposed model provides complex crack paths as a solution to the governing partial differential equations (PDEs), and thus bypasses the need for re-meshing, enrichment of FE shape functions, and an explicit tracking of the crack surfaces. The use of Gridap makes the FE implementation of the proposed model exceedingly compact and user-friendly requiring very low memory usage and providing a high degree of flexibility to the users in defining weak forms of the governing PDEs. We have validated the proposed model and its implementation against a compact tension test on a single edge notched plate and a set of three-point bending tests on a notched beam made of lead zirconium titanate (PZT)-4 piezoelectric ceramics.

Effect of B-site disorder on the electrical properties of Barium Zirconium Titanate Ceramics composites

Effect of B-site disorder on the electrical properties of Barium Zirconium Titanate Ceramics composites

Flexible piezoelectric nanocomposites based on PVDF-HFP/PLA blend doped PZT

In the present work, we studied the effect of adding PZT nanoparticles to PVDF-HFP/PLA matrix on piezoelectric properties of blend-based nanocomposites. Polyvinylidene fluoride hexafluoro-propylene /Polylactic acid /Lead titanate zirconate (PVdF-HFP/PLA/PZT) films nanocomposites were prepared by solvent casting technique using different percentages of PZT Nano fillers. The different samples were characterized by Polarized optical microscope (POM), Fourier transformed infrared (FTIR) and Thermogravimetric analysis (TGA).POM images indicate uniform distribution of PZT Nano fillers in the PVdF-HFP/PLA matrix. FTIR analysis reveals the appearance of β-phase in nanocomposites and the enhancement of their piezoelectric properties. These electroactive nanocomposites thin films are a potential candidate for the piezoelectric Nano generators, energy storage devices and energy harvesting applications.

Potassium sodium niobate (KNN) lead-free piezoceramics: A review of phase boundary engineering based on KNN materials

&lt;abstract&gt; &lt;p&gt;Lead zirconia titanate (PZT) is the most often used piezoelectric material in various electronic applications like energy harvesters, ultrasonic capacitors and motors. It is true that PZT has a lot of significant drawbacks due to its 60% lead content, despite its outstanding ferroelectric, dielectric and piezoelectric properties which influenced by PZT's morphotropic phase boundary. The recently found potassium sodium niobate (KNN) is one of the most promising candidates for a new lead-free piezoelectric material. For the purpose of providing a resource and shedding light on the future, this paper provides a summary of the historical development of different phase boundaries in KNN materials and provides some guidance on how to achieve piezoelectric activity on par with PZT through a thorough examination and critical analysis of relevant articles by providing insight and perspective of KNN, which consists of detailed evaluation of the design, construction of phase boundaries and engineering for applications.&lt;/p&gt; &lt;/abstract&gt;

Synergistic composites energy harvester beams based on hybrid ZnO/PZT piezoelectric nanomaterials

This study aims at elucidating the synergistic effect of the hybridization of two piezoelectric materials: zinc oxide nanowires (ZnO NWs) and a thin film of lead zirconium titanate (PZT), on the mechanical and energy harvesting performance of carbon fiber reinforced polymer composites beams. Novel synthesis techniques were utilized to develop energy-harvesting composite beams with surface-grown ZnO NWs and sputtered PZT thin films. While not an extraordinarily strong piezoelectric material, ZnO NWs enhanced the strength and damping parameter of the composite due to the increased surface area and mechanical interlocking. The composite comprising two piezoelectric materials showed a substantial gain in stiffness, a 25.8% increase compared to plain composite without piezoelectric materials. The hybrid composite energy harvester based on PZT/ZnO NWs exhibited a significant electric power gain of 733.94% more than that for beams with ZnO NWs compared to 44% improvement for a beam utilizing only PZT. Using PZT thin films with ZnO NWs on carbon fiber could yield a high-performance hybrid composite with excellent mechanical properties and energy harvesting capabilities.

Enhanced the dielectric and energy storage properties of BaZr1-xTixO3 lead-free ceramics

Ferroelectric BaZr1-xTixO3 (0 ≤ x ≤ 8) ceramic composition was synthesized by using solid state reaction method. The material was calcined at 1250 °C in air. In this work we have examined that the ferroelectric, energy storage and microwave dielectric properties of BaZr1-xTixO3 at room temperature. The XRD patterns showed that BaZr1-xTixO3 composition is of perovskite structure with a space group of Pm-3m. SEM morphology shows that increase in number of grain boundaries result in increase of polarisation. The energy storage properties were calculated from (P-E) loops by varying the electric field (range) and composition of the ceramic material. It has observed that the relative permittivity increases along with temperature. The storage energy density (Wrec) has been reported 0.043 J/cm3 , whereas efficiency (ɳ) was 57% at room temperature and 40 kv/cm at contents (x=0.06).The Barium zirconium titanate (BZT) will be an excellent candidate material for storage energy devices.

Study on relaxor polymer interface matrix for piezoelectric nanocomposite generators

Piezoelectric nanocomposites consisting of a polymer matrix and ceramic fillers are candidate components of flexible, wearable, and self-powered electronic devices. The physical discrepancy between ferroelectric polymers and ceramics in a piezoelectric interface makes it difficult to assemble efficient hybrid piezoelectric nanocomposites without polarization and extraneous artifacts. Here, we describe the effect of a relaxor ferroelectric terpolymer matrix on the piezoelectric output, which can enhance the energy harvesting or sensor performance of piezoelectric composite device of nanocomposite generators with filler nanoparticles of lead zirconium titanate. The dielectric property and reduced ferroelectric hindrance of the proposed terpolymer matrix provides more poling to align the polarization of piezoelectric ceramic fillers compared with a normal ferroelectric copolymer matrix. Therefore, relaxor ferroelectric polymers can be better than normal ferroelectric polymers as the matrix of hybrid polymer-ceramic piezoelectric nanocomposite. This research provides important physical information about the interface between a polymer matrix and ceramic fillers in flexible piezoelectric nanocomposite applications.

Improved corona discharge-based modified poling method for 0–3 PZT/PEGDA piezoelectric composites

Among piezo composites, 0–3 type ceramic/polymer-based composites have balanced properties and flexible manufacturing processes, allowing them to tackle challenges in wearable electronics and sensing technology. However, due to a misfit between the dielectric coefficients of the ceramic particles and polymer matrix, poling 0–3 composites is difficult. Therefore, in this study, we develop a novel poling method that combines the merits of normal corona poling and oil-based poling methods to activate a lead zirconium titanate (PZT)/Polyethylene glycol diacrylate (PEGDA) composite. The influence of various parameters (voltage, temperature, poling duration, and time of ageing) on the piezoelectric and dielectric properties of the PZT/polymer composite were evaluated. For the 0–3 PZT/PEGDA composites (67 wt%), the optimal poling parameters were found to be 60 min poling duration, 25 °C, and 24 kV. The d33 (32 pC/N) obtained by the proposed poling method is about 3 times that obtained by the normal corona poling method (11 pC/N). This modified poling method was shown to be more effective than the conventional method for a range of filler contents (50 wt%, 67 wt%, and 75 wt%). It was also found that the d33 value of the PZT/PEGDA composite increased over time and was attributed to the increase of the composite dielectric constant after poling. Finally, sensing elements were assembled from the poled samples and evaluated, which shows the potential for detecting tiny signals in sensing and soft robotics.