Piezoelectric Applications Research Articles

Nickel/silver in-situ modification of wearable and stretchable electrodes for textile-based piezoelectric applications

In recent years, smart wearable textiles such as sensors and energy generators have been utilized for various purposes. Such wearable devices require a stretchable and conductive component to communicate with different sections of wearable gadgets and finally send the signals to the processor. This work presents a scalable strategy for the fabrication of electrically enhanced conductive weft-knitted fabric based on a special pattern modified with the in-situ synthesis of two different conductive components consisting of nickel and silver nanoparticles. In addition, in order to investigate their electrical performance, textile-based piezoelectric using the polyvinylidene fluoride-barium titanate (PVDF-BaTiO3) electrospun nanofiber as an active layer was fabricated. The tensile behavior in both directions results revealed that modification with nickel/silver reduced Young’s modulus, maximum specific stress, and maximum strain, although there was no significant alteration in their physical properties. This electrical characterization showed that fabrics possessed piezoelectric output voltage of 0.41, 0.71, and 0.47 times in comparison to aluminum foil in untreated, nickel-treated, and silver-treated cases, respectively. Moreover, the dynamic in-plane electrical sheet resistance demonstrated that untreated, nickel treated and silver-treated electrodes are capable of maintaining their conductivity up to rupture strain under tensile loading conditions in both directions. Indeed, this work provides an approach for highly conductive textile-based electrode fabrication for textile-based piezoelectric applications.

Molecular Engineering of Ordered Piezoelectric Sulfonic Acid-Containing Assemblies.

Sulfonic acid-containing bioorganic monomers with wide molecular designability and abundant hydrogen bonding sites hold great potential to design diverse functional biocrystals but have so far not been explored for piezoelectric energy harvesting applications due to the lack of strategies to break the centrosymmetry of their assemblies. Here, a significant molecular packing transformation from centrosymmetric into non-centrosymmetric conformation by the addition of an amide terminus in the sulfonic acid-containing bioorganic molecule is demonstrated, allowing a high electromechanical response. The amide-functionalized molecule self-assembles into a polar supramolecular parallel β-sheet-like structure with a high longitudinal piezoelectric coefficient d11 = 15.9 pm V-1 that produces the maximal open-circuit voltage of >1V and the maximal power of 18 nW in nanogenerator devices pioneered. By contrast, molecules containing an amino or a cyclohexyl terminus assemble into highly symmetric 3D hydrogen bonding diamondoid-like networks or 2D double layer structures that show tunable morphologies, thermostability, and mechanical properties but non-piezoelectricity. This work not only presents a facile approach to achieving symmetry transformation of bioorganic assemblies but also demonstrates the terminal group and the property correlation for tailor-made design of high-performance piezoelectric biomaterials.

Convergence of alkaline earth and transition metal oxide nanotube properties toward the 2D slab limit, computational investigation for energy conversion implications

Nanoscale devices developed from low-dimensional materials (one and two-dimensional systems) have recently attracted great attention due to their critical applications in micro/nano electromechanics. However, the practical fabrication of 2D systems is often more challenging than that of their 1D counterparts. In the current investigation, the convergence of 1D nanotube properties toward the 2D slab limit has been verified and confirmed. In this regard, a variety of geometrical, electronic, and response (mechanical and piezoelectric) properties are computed for both zigzag (n,0) metal oxide MO (M = Be, Mg, Ca, Zn, Cd) nanotubes and MO 2D surfaces. The variation of such properties as a function of the tube index n (ranging from 6 to 48, corresponding to 24 to 192 atoms per cell, respectively) is highlighted. Additionally, the electronic and nuclear contributions to all aforementioned response properties have been discussed and analyzed. Interestingly, CdO (48,0) nanotube introduces considerable direct and converse piezoelectric constants: e11 = 6.04 |e|×bohr and d11 = 22.88 pm/V. These electromechanical coefficients converge well to the values of the 2D surface, while the response is entirely dominated by the ionic contribution, confirming the flexibility and softness. Such findings make these MO nanotubes good candidates for nanoscale energy conversion piezoelectric applications.

Phase Formation Mechanism and Piezoelectric Behaviour of NaNbO3 Ceramic

The solid state reaction route is adopted to synthesize NaNbO3 with the aim to examine their structural, morphological and electrical behaviour of material with sintering time. The crystal phase is formed without any secondary phase at calcination temperature 800 °C. The article shows the scope of material to be used as a sensor in piezoelectric applications. The synthesized material has been avoided to heat for longer time and has been sintered at 2 h, 4 h and 6 h. The refinement of experimental X-ray diffraction pattern displays crystallization of material in Orthorhombic phase with space group Pbcm and lattice parameters a = 5.513752 Å, b = 5.568852 Å, c = 15.52854 Å, α = β = γ = 90°. A gaussian distribution of grain size with statistical average 0.722 μm, 0.841 μm and 0.842 μm has been observed for NN02, NN04 and NN06 respectively. The NN04 shows maximum piezoelectric coefficient d33* = 110 pm V−1, piezoelectric strain 0.0021% and smallest as asymmetric factor Ys = 0.204 with respect to other investigated samples.

Lead-Free Piezoelectric Energy Harvester Based on 2D Bismuth Titanate.

The use of two-dimensional (2D) layered materials with a noncentrosymmetric structure dramatically increases the potential of nanoscale electromechanical systems and electronic devices. In this work, liquid-phase exfoliation of bulk bismuth titanate was employed to synthesize atomically thin 2D sheets and fabricate a high-performance piezoelectric energy harvester. The structural and morphological properties of the 2D sheets were analyzed, confirming their phase purity and layer formation. Piezoelectric properties of the 2D sheets were evaluated using Piezoresponse Force Microscopy (PFM), demonstrating a high d33 piezoelectric coefficient of 40 pm/V in a few-layer bismuth titanate nanosheet. A prototype energy harvesting device was fabricated with 2D bismuth titanate as the active material. The piezoelectric response of the fabricated device was recorded at different frequencies and forces, which yielded a maximum d33 of 57.8 pC/N at 1 Hz. Such a solid electromechanical performance at a relatively infinitesimal input response indicates that 2D bismuth titanate can be useful for piezoelectric energy harvesting applications.

The Role of Molecularly Imprinted Polymers In Sensor Technology: Electrochemical, Optical and Piezoelectric Sensor Applications

With the help of molecular imprinting technology, artificial receptors can be made and used for identification. This technique's limitless application increases polymer technology and makes it adaptable to other technologies. In this study, examples of sensor applications are used to explain molecular imprinting technology (MIT) and its brief history. MIT can be used to create polymer-based artificial receptors with remarkable selectivity and affinity to detect any target molecules that can be imprinted on a polymer. A monomer is synthesized around a template molecule to create a selective cavity that serves as an artificial receptor. Molecularly imprinted polymers (MIP) offer a wide range of uses and have recently garnered much attention. These polymers' production methods, production kinds, and molecular imprinting techniques are all thoroughly detailed. The outstanding properties of MIPs make a crucial contribution to sensor applications offering selective, fast, easy, and cost-effective analysis, which became very popular after Clark published his first biosensor study. Apart from the biological recognition receptors, MIPs have the advantage that they are not affected by physical conditions of the environment, such as temperature, pH, and ion strength. To overcome the biological recognition receptors' disadvantages, molecularly imprinted polymers can be used for sensor development. From the point of view of the review, the combination of MIPs and sensors was explained and proposed as an informative paper.

Lead zirconate titanate-based ceramics with high piezoelectricity and broad usage temperature range

Piezoceramics have long faced the challenge of achieving both a high Curie temperature (TC) and outstanding electrical properties due to thermal depolarization. To address this, we introduced a novel two-step synergistic strategy in synthesizing lead zirconate titanate (PZT)-based x[(1–y)BiYO3-yFe2O3)]-(1–x)Pb(Zr0.53Ti0.47)O3 [abbreviated as xBYF(y)-PZT] ceramics, where co-doping of Fe2O3 and BiYO3 significantly influences dielectric and piezoelectric properties. Our breakthrough composition, 0.01BYF(0.6)-PZT, showcases a unique coexistence of rhombohedral and tetragonal phases. It boasts impressive figures, including a piezoelectric coefficient d33 of 467 pC N−1, a TC of 381 °C, an electromechanical coupling coefficient (kp) of 68%, and a coercive field (Ec) of 12 kV cm−1, displaying both “softening” and “hardening” characteristics. In-depth analysis with in-situ X-ray diffraction and transmission electron microscopy unveils the critical role of multiphase coexistence and local heterostructures in enhancing piezoelectric responses through synergistic effects. Notably, this innovative composition with x = 0.01 showcases exceptional thermal stability across a broad operating temperature range (30–350 °C) and delivers an in-situ d33 value of 790 pC N−1. These compelling findings underscore the potential of BYF-modified PZT ceramics as promising candidates for high-temperature piezoelectric applications.

Ultra-high Curie temperature transparent piezoelectric Bi doped Ca2Nb2O7 single crystals

Ca2Nb2O7 is a promising material for high-temperature piezoelectric applications due to its ultra-high Curie temperature, which makes it a suitable candidate for use in harsh environments. However, their piezoelectric performance needs improvement. Here, through chemical engineering methods, we have successfully grown Bi3+ doped Ca2Nb2O7 single crystals using the optical floating zone technique. The Ca1.94Bi0.06Nb2O7 single crystals achieved better high-temperature stability, transparency and a higher piezoelectric constant of 12.8 pC/N at 298 K and 20.0 pC/N at 660 K. In addition to the dopant effects, mechanisms for enhancing the piezoelectric properties of perovskite-like layer structure (PLS) materials have been identified, highlighting the significant contribution of the NbO6 octahedron and interlayer ions. These findings offers valuable insights into improving the performance of PLS materials, which is crucial for promoting their practical applications as high-temperature lead-free piezoelectric materials.

Giant Ferroelectric and Piezoelectric Properties of Lead Free Ba0.85Ca0.15Ti0.90Zr0.10O3 Thin Film in 100 nm Thickness Range

Lead‐free Ba0.85Ca0.15Ti0.90Zr0.10O3/SrRuO3 (BCZT/SRO)‐heterostructured thin film grown on (001)‐SrTiO3 substrate is prepared by pulse laser deposition. The microstructure, ferroelectric, and piezoelectric of the thin film are investigated in detail. Giant ferroelectric properties of the BCZT thin films with thickness ≈100 nm and remanent polarization Pr of 57.1 μC cm−2 are obtained, which are attributed to the (00L)‐oriented epitaxial structure and lower substrate clamping. In addition, the BCZT/SRO heterostructure exhibits excellent piezoelectric properties with the d33 values of different grain size (40–140 nm) varied from 75 to 130 pm V−1, providing a potential candidate used as piezoelectric material for magnetoelectric composite films. The BCZT/SRO‐heterostructured thin film with excellent ferroelectric and piezoelectric properties may be a good alternative to Pb(ZrxTi1−x)O3 thin films for piezoelectric device applications.

Is there any difference on fertilization and blastulation rates of sibling oocyte activated by piezo-electric or ca ionophore application?

Is there any difference on fertilization and blastulation rates of sibling oocyte activated by piezo-electric or ca ionophore application?

Electro-mechanical transfer matrix modeling of piezoelectric actuators and application for elliptical flexure amplifiers

Mechanically amplified piezoelectric actuators (APAs) can be found in many scenarios of precision engineering and instrumental devices. However, the electro-mechanical design of curvilinear APAs is difficult due to the existence of curved flexure beams and multi-domain electro-elasto dynamics. In this paper, the electro-mechanical behavior of elliptical APAs is studied by exploiting a novel electro-mechanical transfer matrix method. The motivation is to facilitate both the static and dynamic analyses of such a complex APA with curvilinear flexure beams by considering the multi-domain dynamics of piezoelectric stacks and compliant mechanisms from an electro-mechanical viewpoint. To this end, an analytical electro-elasto transfer matrix of piezoelectric stacks operating at the d33 mode is derived in the form of Taylor's series based on Timoshenko beam theory. The dynamic response spectrum of displacement and impedance for elliptical APAs are insightfully captured by such an electro-mechanical model. Different topologies of elliptical APAs are also compared and the optimal configuration is suggested. At last, a proof-of-concept prototype is fabricated and tested with a special focus on experimental evaluation of the electro-mechanical coupling model.

Improved dielectric and piezoelectric thermal stability by chemical homogenization in CuO-modified 0.75BiFeO3-0.25BaTiO3 piezoceramics

0.75BiFeO3-0.25BaTiO3 lead-free ceramics have been considered promising candidates for high-temperature piezoelectric applications. However, their dielectric and piezoelectric properties severely degrade with increasing temperature. In this work, improved dielectric and piezoelectric thermal stability was obtained in CuO-modified 0.75BiFeO3-0.25BaTiO3 ceramics. CuO addition increases the volume fraction of the rhombohedral phase in the 0.75BiFeO3- 0.25BaTiO3 ceramics and makes the chemical heterogeneity disappear. The dielectric and piezoelectric anomalies are eliminated near 300 °C and return with CuO additions, and the temperature degradations of the dielectric constant and piezoelectric coefficient of 0.75BiFeO3-0.25BaTiO3 ceramics with 0.008 mol CuO in the range from 25 to 400 °C decrease by 85% and 60%, respectively. Furthermore, the depoling temperature and piezoelectric coefficient of 0.75BiFeO3-0.25BaTiO3 ceramics with 0.008 mol CuO are 570 °C and 131 pC/N, respectively. These results indicate that CuO addition is an effective approach to improve both the dielectric and piezoelectric thermal stability of 0.75BiFeO3-0.25BaTiO3 ceramics.

Comparative investigations of structural, electronic, optical, and thermoelectric properties of pure and 2 at. % Al-doped ZnO.

We comparatively investigate the properties of pure ZnO and 2 at. % Al doping concentration of ZnO, AZO, as potential candidates for specific applications. Calculations were carried out, using Wien2k package, to deduce structural, electronic, optical thermoelectric, and properties of both ZnO and AZO materials via the combination of GGA and mBJ approximations. It is shown that Al doping of ZnO (AZO) improves its optical properties; the deduced direct fundamental gap is enhanced due to the Burstein-Moss effect. Moreover, the dielectric function, at lower energies, confirms the existence of an extra strong fluctuation in the dispersive real part ɛ1(ω) and a high peak for absorptive imaginary parts ɛ2(ω) which are due to a variation in specific molecular bonding and the transition between the occupied and the non-occupied states. The critical point, observed at 2.81 eV for pure ZnO, is shifted to 3.3 eV in 2 at. % AZO, confirming a larger optical band gap. The reflectivity values slightly decreased for 2% AZO. The investigation of thermoelectric parameters as a function of chemical potential at different temperatures ranging from 300 to 900°C showed that these structures can be considered for good thermoelectric devices with (i) high absolute values of Seebeck coefficient: ׀SZnO׀ = 1.16 mV/K and ׀SAZO׀ = 0.746 mV/K, (ii) no effect of temperature on electrical conductivity but a strong effect on thermal conductivity, (iii) a high value approaching unity for the figure of merit. Hence, these properties and their improvements, introduced by Al doping of ZnO, lead specific and more uses in optoelectronics, energy, and piezoelectric applications.

Effect of Hexamethylenetetramine of Zinc Oxide Nanowires Using Chemical Bath Deposition Method

AbstractIn this study, zinc oxide (ZnO) nanowires are grown by chemical bath deposition (CBD) using aqueous solutions with [Zn (NO3)2]: [HMTA] ratios of 1:2/5, 1:1/2, 1:2/3, 1:1, 1:2, and 1:3. The effects of hexamethylenetetramine (HMTA) on the formation of Zinc oxide (ZnO) nanowires are investigated. The XRD results reveal that the dominant peak observed at 2θ = 36.25° indicates preferential growth along the (101) crystal plane, and the ZnO nanowires have a larger crystallite size than the others. The length of the ZnO nanowires, grows with a ZnO seed in the thickness of one and three layers, gets increased from 256.16 ± 15.15 to 497.80 ± 7.84 nm, while the diameter decreases from 497.80 ± 7.84 to 50.34 ± 4.23 nm. The ZnO nanowires deposited by one layer show a similar pattern with the three layers, in which the length is increased from 8.44 ± 0.31 to 14.60 ± 0.51 µm, and the diameter has decreased from 1.95 ± 0.09 to 0.49 ± 0.06 µm. These results support the role of HMTA as a capping agent for the production of ammonia (NH3). This study can control the dimensions of ZnO nanowires using the HMTA concentration to obtain extra‐long nanowires desired for piezoelectric applications.

Magnetron Sputter Deposition of Nanostructured AlN Thin Films

Aluminum nitride (AlN) is a material of growing interest for power electronics, fabrication of sensors, micro-electromechanical systems, and piezoelectric generators. For the latter, the formation of nanowire arrays or nanostructured films is one of the emerging research directions. In the current work, nanostructured AlN films manufactured with normal and glancing angle magnetron sputter depositions have been investigated with scanning and transmission electron microscopy, X-ray diffraction, atomic force microscopy, and optical spectroscopy. Growth of the nanostructures was realized utilizing metal seed particles (Ag, Au, and Al), allowing the control of the nucleation and following growth of AlN. It was demonstrated how variations of seed particle material and size can be used to tune the parameters of nanostructures and morphology of the AlN films. Using normal angle deposition allowed the growth of bud-shaped structures, which consisted of pillars/lamellae with wurtzite-like crystalline structures. Deposition at a glancing angle of 85° led to a film of individual nanostructures located near each other and tilted at an angle of 33° relative to the surface normal. Such films maintained a high degree of wurtzite-like crystallinity but had a more open structure and higher roughness than the nanostructured films grown at normal incidence deposition. The developed production strategies and recipes for controlling parameters of nanostructured films pave the way for the formation of matrices to be used in piezoelectric applications.

Flexible electrospun PVDF/WO3 nanocomposite fibers for piezoelectric energy harvesting applications

AbstractThe emerging field of energy harvesting depends on the electrically conductive materials that are highly flexible and deformable. The morphological, structural, thermal, mechanical, and piezoelectric output studies of electrospun polyvinylidene fluoride (PVDF) and PVDF/WO3 nanorods composite nanofibers were investigated for the piezoelectric energy harvesting applications. There is a significant enhancement in the piezoelectric β phase after the addition of the WO3 nanorods into the PVDF. The elemental composition of the PVDF/WO3 nanorods composite nanofibers is confirmed by the W, O, F, and C elements. The thermal stability of the WO3 nanorods added composite nanofibers was increased up to 30°C in reference to TGA responses. Based on the mechanical test, the maximum tensile strength and modulus of elasticity were enhanced around by 220 and 246% for the WO3‐integrated PVDF nanofibers. Furthermore, the piezoelectric coefficient of 18.98 pC/N is achieved for the composite PVDF nanofibers which are mainly due to the improvement of the electroactive β phase. The piezoelectric energy harvesting responses were found an output voltage of 2.1 V based on the microstrain set‐up. Thus, these WO3 nanorods incorporated PVDF nanofibers keep the great potential for the piezoelectric energy harvesting, wearable electronics and biomedical applications.

On Integration of Vibration Suppression and Energy Harvesting Through Piezoelectric Shunting With Negative Capacitance

While negative capacitance (NC) element has the potential of increasing the apparent electro-mechanical coupling in various piezoelectric applications, it generally requires a power supply which may negate its benefit. Indeed, there has been no systematic analysis of NC power consumption in piezoelectric circuitry. In this article, we investigate the combinatorial effect of NC circuit on an integrated design of passive vibration suppression and energy harvesting with <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> resonant shunt. We first conduct a power consumption analysis of a representative NC circuit and analyze its influence on piezoelectric energy harvesting. We then explore the tradeoff between vibration suppression through <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> shunt with NC element and the net power generation of the energy harvester. It is identified that there exists a range of NC values within which the vibration suppression performance is enhanced while the net power generation remains to be positive. This effectively yields a self-sustainable vibration suppression enhancement scheme with an NC element. Correlated numerical and experimental studies confirm this new finding.

Optimizing piezoelectric properties and temperature stability via Nb2O5 doping in PZT-based ceramics

High-performance piezoelectric ceramics with temperature stability can significantly enhance the functionality of transducers and sensors across a range of piezoelectric device applications. In this study, we investigated ceramics composed of 0.16Pb0.92Ba0.08(Mg0.5W0.5)O3-0.84 Pb(Zr0.43Ti0.57)O3 (PBMW-PZT) with varied Nb2O5 content. Notably, the ceramic doped with 1.0 wt% Nb2O5 exhibited superior piezoelectric properties (d33 ∼ 596 pC/N, kp ∼ 67%, and Tc ∼ 284 °C). Moreover, this ceramic demonstrated a stable performance with variations below 10% in the temperature range from 20 °C to 240 °C, surpassing many commercially available PZT-based ceramics. A combination of XRD, SEM, ferroelectric studies, and other in situ analytical methods indicated that this heightened piezoelectric response arises from a marked increase in reversible domain wall movement. The temperature-responsive Raman spectra suggest that the material's temperature stability primarily stems from its inherent structural integrity. Given these findings, the ceramic material in question emerges as an optimal choice for applications in piezoelectric devices, especially transducers and sensors.

Direct Control of Pt Film Orientation for Growth of (100)-oriented PZT Films

We investigated highly (100)-oriented PZT films directly grown on Pt films coated on RuO2/SiO2/Si substrates via sputtering method. By controlling the preferred (100) orientation volume of the Pt films, we confirmed the effectiveness of high (100) orientation of Pt films suitable for the growth of highly (100)-oriented PZT films. Particularly, as the (100) orientation region of Pt film is larger than 90%, the PZT film with 95% of (100) orientation region can be formed, without using any seed layer as well as epitaxial growth process. We found that a highly (100)-oriented PZT film possesses large grains with a size of 150 nm, and it possesses twice remanent polarization of 58 mC/cm2 and coercive electric field of 148 kV/cm with the relatively low leakage current less than 10-6 A/cm2 at the applied voltage of ± 4 V. One can convince that the technological process for highly (100)-oriented PZT films is simple, and it is promising for ferroelectric and piezoelectric applications in wide ranges. &#x0D;

Free-standing 2D gallium nitride for electronic, excitonic, spintronic, piezoelectric, thermoplastic, and 6G wireless communication applications

Two-dimensional gallium nitride (2D GaN) with a large direct bandgap of ~5.3 eV, a high melting temperature of ~2500 °C, and a large Young’s modulus ~20 GPa developed for miniaturized interactive electronic gadgets can function at high thermal and mechanical loading conditions. Having various electronic, optoelectronic, spintronic, energy storage devices and sensors in perspective and the robust nature of 2D GaN, it is highly imperative to explore new pathways for its synthesis. Moreover, free-standing sheets will be desirable for large-area applications. We report our discovery of the synthesis of free-standing 2D GaN atomic sheets employing sonochemical exfoliation and the modified Hummers method. Exfoliated 2D GaN atomic sheets exhibit hexagonal and striped phases with microscale lateral dimensions and excellent chemical phase purity, confirmed by Raman and X-ray photoelectron spectroscopy. 2D GaN is highly stable, as confirmed by TGA measurements. While photodiode, FET, spintronics, and SERS-based molecular sensing, IRS element in 6G wireless communication applications of 2D GaN have been demonstrated, its nanocomposite with PVDF exhibits an excellent thermoplastic and piezoelectric behavior.