Piezoelectric Enhancement Research Articles

Interface modulated 0-D piezoceramic nanoparticles/PDMS based piezoelectric composites for highly efficient energy harvesting application

Abstract Flexible piezoelectric nanogenerator (PENG) has been regarded as one of the promising solutions to harvesting mechanical energy, as a sustainable energy source for wearable devices, etc. Here, a universal strategy of carbon coating modulation is proposed to synthesis carbon coated 0-D piezoceramics nanoparticles (NPs). Owing to the good electric conductivity of carbon shell, the redistribution and accumulation of mobile charges in carbon layer gives rise to reinforcement of electric field, results in the much-enhanced piezoelectric effect. Polydimethylsiloxane (PDMS) composites with those 0-D piezoceramics NPs are used to fabricate PENGs. The peak power density of BT@C, PZT@C and KNN@C based PENGs reaches up to 45.4 μW/cm2, 59.8 μW/cm2 and 9.9 μW/cm2, that are 20, 20.4 and 13.4 times larger than those of control PENGs incorporated with bare 0-D piezoceramic NPs, respectively. A theoretical model based on Lewis diffusion theory is constructed to reveal the mechanism of piezoelectric enhancement in the poling process. This research provides a new strategy for synthesis of high piezoelectric characteristic composites by embedding carbon coated 0-D piezoceramic NPs.

Piezoelectric energy enhancement strategy for active fuzzy harvester with time-varying and intermittent switching

This study aims to increase the amount of electrical energy harvested from a piezoelectric vibration energy harvester under unloaded and high-load resistance conditions. Although increased piezoelectric charge due to the synchronized switch harvesting on inductor (SSHI) strategy damps mechanical vibrations, the mechanical vibration amplitude of a mechanical element in a harvester is assumed to be constant for most discussions regarding the active harvester with SSHI strategy. However, this assumption is not valid under excessive switching actions, in which case the performance of the harvester deteriorates. This problem is known as the vibration suppression effect. To address this problem, in this study, two switching strategies for the charge inversion circuit—namely, switching considering vibration suppression-threshold (SCVS-t) and adaptive SCVS-t (ASCVS-t)—are proposed through intermittent switching actions. During the harvesting process, intermittent switching using these strategies is performed based on the output voltage threshold, thus maintaining high mechanical vibration amplitude and excellent harvesting performance by avoiding excess switching. The ASCVS-t adopts a tuning algorithm for the time-varying threshold and can achieve appropriate intermittent switching and effective harvesting under various vibration conditions without pre-tuning. Experimental comparisons with conventional strategies confirm that the proposed strategies achieve 2.9 times and 2.0 times greater harvested energy storages than a standard harvester and conventional switching strategy, respectively.

Series Synchronized Triple Bias-Flip Circuit: Maximizing the Usage of a Single Storage Capacitor for Piezoelectric Energy Harvesting Enhancement

The synchronized multiple bias-flip (SMBF) interface circuits enhance the piezoelectric energy harvesting (PEH) capability by maximizing the extracted energy from the piezoelectric source and simultaneously minimizing the dissipated energy in the power conditioning circuit. They provide the most energy-economic solution for the piezoelectric energy harvesting enhancement. However, the growing scale of the switches network and the increasing number of bias voltages have added much complexity to the circuit design and control. In this article, we reduce the number of passive components to the biggest extent by maximizing the usage of a single capacitor, which simultaneously acts as an energy storage and provides two nonzero bias voltages. Together with the free zero-volt bias, triple bias-flip actions (S3BF) are realized in the new design. Compared with other single-capacitor designs, it makes the best energy harvesting capability so far. Moreover, the proposed series S3BF circuit can automatically shift among single, double, and triple bias-flip operations under heavy-, medium-, and light-load conditions, respectively, which is unprecedented in the previous designs. Theoretical and experimental results show that the harvested power can always follow the maximum power envelope of the single, double, or triple bias-flip operations.

Defect-Mediated Piezoelectricity in Boron Nitride Nanotube

Introduction A zigzag boron nitride nanotube (ZBNNT) has a large intrinsic polarized dipole and a piezoelectric tunability with crystal chirality, nanotube diameter, and point defect. The piezoelectric coefficients (e33) of 8-ZBNNT with the VIA-group defects of SN and SeN are estimated to be 18.7×10-2 C/m2 and 14.9×10-2 C/m2, respectively. The coefficients of defect-mediated 8-ZBNNT are 97% and 57% bigger than that of pristine 8-ZBNNT. The elastic modulus of 8-ZBNNT is decreased due to the VIA-group defects, but is increased for the larger number of unit cells along zigzag rolling direction. The electronic band gap of 8-ZBNNT is reduced due to the VIA-group defects. The large piezoelectricity enhancement of 8-ZBNNT with VIA-group defect is attributable to the enhanced piezoelectricity from ionic contribution. Therefore, the unprecedented defect-mediated 8-ZBNNT provides a new material platform of mechanoelectronic devices for nanoscale sensors and energy conversions. Modeling and methodology Figure 1 shows the schematic of a single wall 8-ZBNNT with an atomic defect. The supercell is in a simple orthorhombic box with periodic boundary condition in 30 Å × 30 Å × Lc where Lc is the lattice parameter along the transport direction. The green atom “A” indicates the defect of a single substitution atom per a supercell. The average bond length is defined as the average length of atomic bond between the defect doping atom and the neighboring boron atoms. The first principle calculations were carried out by using the Virtual Nanolab Atomistix ToolKit (ATK) package with the density functional theory (DFT). The localized density approximation (LDA) exchange correlation with a double zeta polarized (DZP) basis was used with a mesh cut-off energy of 150 Ry. All atomic positions and lattice parameters were optimized by using the generalized gradient approximations (GGA) with the maximum Hellmann Feynman forces of 0.05 eV/Å, which was sufficient to obtain relaxed structures. The maximum number of fully self-consistent field (SCF) iteration steps was set to 100. Defect-mediated piezoelectricity The table I includes the piezoelectric coefficient (e33) and average bond length (a0) of 10- and 8-ZBNNT with different kinds of defects including SW deformation, IVA-group, and VIA-group defects within one supercell. Among the defects in ZBNNT, a single nitrogen vacancy or SW defect diminishes the piezoelectric coefficient (e33) of 10- and 8-ZBNNT. However, the atomic defects of IVA- and VIA-group elements in a nitrogen site enhance the piezoelectric coefficient. The piezoelectric coefficient of VIA-group defect is higher than that of IVA-group defect. The piezoelectric coefficient e33 of chalcogen defect SN and SeN in 8-ZBNNT is enhanced 97% and 57% from 9.49×10-2 C/m2 to 18.7×10-2 C/m2 and 14.9×10-2 C/m2, respectively, compared to that of pristine 8-ZBNNT. The table I includes the elastic modulus of pristine10-ZBNNT and 8-ZBNNT and the ZBNNT with defects. The elastic modulus of 10- and 8-ZBNNT with defects is smaller than that of pristine 10- and 8-ZBNNT. The elastic modulus of SW defects in ZBNNT is increased compared to that of pristine 10- and 8-ZBNNT. The structure with smaller elastic modulus has the larger strain response to the constant external stress. Therefore, the ZBNNT with IVA- and VIA-group atomic defects has an efficient response to the external stress for piezoelectric applications. 8-ZBNNT of SN and SeN with the smaller elastic modulus have the larger e33 compared to the structure with ON. Defect-mediated electronic band structure Figure 2 shows the electronic band structure of 8-ZBNNT with (a) pristine structure and (b) defects of ON, SN and SeN. The group VIA-group defects in 8-ZBNNT are n-type doping because the Fermi level is located in the conduction band while the VIA-group defects in 8-ZBNNT are p-type doping. The bandgap in 8-ZBNNT is also reduced from 3.37 eV to 3.16 eV, 3.12 eV and 3.20 eV for the VIA-group defect of ON, SN and SeN, respectively. However, the band gaps of 8-ZBNNT with the IVA-group defects of CN, SiN and GeN is slightly widened to 3.38 eV, 3.49 eV and 3.50 eV compared to the band gap 3.37 eV of pristine 8-ZBNNT, respectively. Conclusions The piezoelectricity of ZBNNT is significantly enhanced by atomic defects. The piezoelectric coefficients (e33) 8-ZBNNT with SN and SeN defects are increased up to 97% and 57%, respectively. The electronic band gap of 8-ZBNNT with defects is reduced. The large piezoelectricity enhancement of 8-ZBNNT with VIA-group defect is attributable to the enhanced piezoelectricity from ionic contribution. Therefore, the unprecedented defect-mediated 8-ZBNNT provides a new material platform of mechanoelectronic devices for nanoscale sensors and energy conversions. Acknowledges This work is supported by ARO W911NF-15-1-0535, NSF HRD-1137747, and NASA NNX15AQ03A. Figure 1

Self-powered artificial skin made of engineered silk protein hydrogel

Abstract Engineered silk protein hydrogel that resembles skin tissue is a promising material for artificial electronic skin; it can be interfaced with real biological tissues seamlessly and used as an artificial tissue in soft robotics. Herein, we report a soft, biocompatible, and skin-adhesive silk hydrogel incorporating ZnO nanorods (ZnONRs) for a tribo- and piezo-electric energy-generating skin (EG-skin) that can harvest biomechanical energy and sense biomechanical motions. Incorporation of ZnONRs mediates an eight-fold enhancement of piezoelectricity compared to pristine silk hydrogel. An additional two-fold increase in the electrical response is possible when it is encapsulated in silk protein layers because of the hybrid effect of tribo- and piezo-electricity. The high power generated (~1 mW/cm2) is sufficient to activate low-power electrical devices, such as LEDs, oximeters, and stopwatches. Additionally, the EG-skin can be used as a tactile identifier for finger movements with quantized real-time electrical signals. The softness and skin-adhesive properties provide conformal interfaces with human skin and biological tissues, and we can harvest energies of approximately 6.2 and 0.9 μW/cm2, respectively, from their mechanical stimulation. The silk-protein-based artificial EG-skin can be effectively utilized in human–machine interfaces, tactile sensors, soft robotics, and biomedical implants.

Synergetic Contributions in Phase Boundary Engineering to the Piezoelectricity of Potassium Sodium Niobate Lead-Free Piezoceramics.

Although the pronounced piezoelectricity was obtained in (K, Na)NbO3 piezoceramics with the phase boundary engineering (PBE), the physical mechanisms remain pending. Here, we revealed for the first time how PBE influences the piezoelectric properties through synergetic contributions. Cryogenic experiments confirm that PBE constructs a phase coexistence, consisting of rhombohedral (R), orthorhombic (O), and tetragonal (T) phases, with a structural softening, by which a high piezoelectric coefficient d33 of 555 pC/N and the enhanced temperature stability of strain are achieved. The phenomenological theory and transmission electron microscopy demonstrate that the superior d33 hinges on the flattened Gibbs free energy and the abundant nanodomains (10-80 nm), which induce the enhanced permittivity and the coexisting single domain and multidomain zones, respectively. In particular, we disclosed a trade-off relationship between ferroelectric domains and polar nanoregions (PNRs) and found the "double-edged sword" role of PNRs in the piezoelectricity enhancement. Therefore, this work helps understand the physical mechanisms of the piezoelectricity enhancement, benefiting the future research of lead-free piezoceramics.

Effect of passivation on piezoelectricity of ZnO nanowire

Surface passivation is one valuable approach to tune the properties of nanomaterials. The piezoelectric properties of hexagonal [001] ZnO nanowires with four kinds of surface passivations were investigated using the first-principles calculations. It is found that in the 50% H(O) and 50% Cl(Zn), 50% H(O) and 50% F(Zn) passivations, the volume and surface effects both enhance the piezoelectric coefficient. This differs from the unpassivated cases where the surface effect was the sole source of piezoelectric enhancement. In the 100% H, 100% Cl passivations, the piezoelectric enhancement is not possible since the surface effect is screened by surface charge with weak polarization. The study reveals that the competition between the volume effect and surface effect influences the identification of the diameter-dependence phenomenon of piezoelectric coefficients for ZnO nanowires in experiments. Moreover, the results suggest that one effective means of improving piezoelectricity of ZnO nanowires is shrinking axial lattice or increasing surface polarization through passivation.

Metal-organic frameworks Co3[Co(CN)6]2: A promising candidate for dramatically reinforcing the piezoelectric activity of PVDF

Over decades, the exploration of poly(vinylidene fluoride) (PVDF) based composites with outstanding piezoelectric activity has gained great popularity and interest from diverse research communities because of their potential in realizing flexible sensors and energy harvesters. Herein, in this work, we reported a novel high performance PVDF based piezoelectric composites containing Metal-organic frameworks (MOF) Co3[Co(CN)6]2. The ultra-high specific surface area and unique open framework nanostructure of Co3[Co(CN)6]2 demonstrated to be efficient in inducing strong interfacial coupling effect within PVDF, resulting in piezoelectricity enhancement. Moreover, the redox behavior of metal ions in Co3[Co(CN)6]2 which provides pathway for electrons, was anticipated to further hardness the interfacial coupling effect and consequently piezoelectric reinforcing effect. Upon an addition of 0.6 wt% Co3[Co(CN)6]2, the piezoelectric response of composites reached the maximum, i.e. a d33 and a d31 of 37 pC/N and 33 pC/N, respectively, which are both almost double those of PVDF. Furthermore, the resultant composites exhibited superior electromechanical coupling factor k31 up to 0.135 while that of pure PVDF was only 0.078. For the first time, we present the applicability of MOF as a new class of reinforcing fillers for piezoelectric composites, providing a new perspective to develop PVDF based composites with superior piezoelectric response.

Impact of Phase Structure on Piezoelectric Properties of Textured Lead-Free Ceramics

The impact of phase structure on piezoelectric performances of <001> textured Na0.5Bi0.5TiO3 (NBT) based lead-free ceramics was studied, including 0.88NBT-0.08K0.5Bi0.5TiO3-0.04BaTiO3 (88NBT) with morphotropic phase boundary (MPB) composition and 0.90NBT-0.07K0.5Bi0.5TiO3-0.03BaTiO3 (90NBT) with rhombohedral phase. Both textured ceramics exhibit a high Lotgering factor, being on the order of f~96%. The piezoelectric coefficients of the textured 88NBT and 90NBT ceramics are increased by 20% and 60%, respectively, comparing to their randomly oriented ceramics. The piezoelectric enhancement of 90NBT textured ceramic is three times higher than 88NBT, revealing the phase structure plays a significant role in enhancing the piezoelectric performances of textured ceramics. Of particular significance is that the 90NBT textured ceramic exhibits almost hysteresis-free strain behavior. The enhanced piezoelectric property with minimal strain hysteresis is attributed to the <001> poled rhombohedral engineered domain configuration.

Enhancement of Photoemission on p-Type GaAs Using Surface Acoustic Waves.

We demonstrate that photoemission properties of p-type GaAs can be altered by surface acoustic waves (SAWs) generated on the GaAs surface due to dynamical piezoelectric fields of SAWs. Multiphysics simulations indicate that charge-carrier recombination is greatly reduced, and electron effective lifetime in p-doped GaAs may increase by a factor of 10× to 20×. It implies a significant increase, by a factor of 2× to 3×, of quantum efficiency (QE) for GaAs photoemission applications, like GaAs photocathodes. Conditions of different SAW wavelengths, swept SAW intensities, and varied incident photon energies were investigated. Essential steps in SAW device fabrication on a GaAs substrate are demonstrated, including deposition of an additional layer of ZnO for piezoelectric effect enhancement, measurements of current–voltage (I–V) characteristics of the SAW device, and ability to survive high-temperature annealing. Results obtained and reported in this study provide the potential and basis for future studies on building SAW-enhanced photocathodes, as well as other GaAs photoelectric applications.

Phase transitions and piezoelectricity enhancement around MC → O phase transition in PMN-0.34PT single crystals

Abstract Phase transitions of Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 (PMN-0.34 PT) have been studied by using dielectric constant variations, polarization-electric field hysteresis loops, and polarizing light microscopy (PLM). Even without the assistance of electric field, orthorhombic (O) phase exists in the [001]C-oriented PMN-0.34 PT single crystals during the heating process, which is confirmed by the polarizer/analyzer extinction angle from full-angle in situ PLM observation combined with the grayscale image analysis. The phase transition sequence is monoclinic (MC) → O → MC → tetragonal (T) → cubic (C), which is different from the commonly accepted MC → T → C sequence. The existence of the O phase accompanies with much enhanced dielectric and piezoelectric performance, which indicates a new mechanism to produce large piezoelectricity in PMN-PT single crystals.

Atomic scale study of the oxygen annealing effect on piezoelectricity enhancement of (K,Na)NbO3 nanorods

An atomic-scale study of the oxygen annealing effect on the piezoelectricity enhancement of (K,Na)NbO3 nanorods via structure, strain and dipolar displacement vector analyses.

Practical high-performance lead-free piezoelectrics: structural flexibility beyond utilizing multiphase coexistence.

Due to growing concern for the environment and human health, searching for high-performance lead-free piezoceramics has been a hot topic of scientific and industrial research. Despite the significant progress achieved toward enhancing piezoelectricity, further efforts should be devoted to the synergistic improvement of piezoelectricity and its thermal stability. This study provides new insight into these topics. A new KNN-based lead-free ceramic material is presented, which features a large piezoelectric coefficient (d33) exceeding 500 pC/N and a high Curie temperature (Tc) of ∼200°C. The superior piezoelectric response strongly relies on the increased composition-induced structural flexibility due to lattice softening and decreased unit cell distortion. In contrast to piezoelectricity anomalies induced via polymorphic transition, this piezoelectricity enhancement is effective within a broad temperature range rather than a specific small range. In particular, a hierarchical domain architecture composed of nano-sized domains along the submicron domains was detected in this material system, which further contributes to the high piezoelectricity.

Multiple contributions to electrostrain in high performance PbTiO3−Bi(Ni1/2Hf1/2)O3 piezoceramics triggered by phase transformation

Piezoelectric materials, which mechanically respond to electrical stimulation and vice versa, typically exhibit high piezoelectricity at a morphotropic phase boundary (MPB). A thorough structural description is essential for understanding the origin of excellent piezoelectric properties. Herein, a comparative study of electric-field-driven structure and phase evolution has been conducted on MPB and non-MPB tetragonal composition in high performance system of PbTiO3–Bi(Ni1/2Hf1/2)O3 piezoceramics using in situ high-energy synchrotron X-ray diffraction. The results show that the MPB composition exhibits electric-field-driven reversible tetragonal-to-monoclinic transformation, whereas non-MPB composition does not. Direct evidence shows that the extensive phase transformation triggers multiple contributions to enhancing piezoelectric performance. Namely, it not only enables the unit cell parameters of coexisting phases easily change with an external electric field, but also enhances the domain switching and lattice strain. These results offer a unique perspective on MPB associated piezoelectricity enhancement, and will be helpful for developing high performance piezoelectric materials.

The influence of electrical field on (K,Na)NbO3-based ceramics over polymorphic phase transition composition region

By investigating the responding behavior of Li modified (K,Na)NbO3 ceramics under external electrical field, a coincidence phenomenon had been observed. It was found that the amplitude of piezoelectricity enhancement for these ceramics with pure orthorhombic, coexistence and tetragonal phase were consistent with the variation amplitude for the transition temperature from orthorhombic to tetragonal (TO-T). The interpretation of the remnant polarization (Pr) had rationally demonstrated the enhancement of piezoelectricity for these three kinds of ceramics. The residual polarization energy induced by remnant polarization (Pr) was about to affect the thermodynamic equilibrium state of these ceramics and accordingly ΔTO-T varied with these poled ceramics.

Piezoelectric enhancement of a defect-mediated boron nitride nanotube

A zigzag boron nitride nanotube (ZBNNT) has a large intrinsic polarized dipole and a piezoelectric tunability with crystal chirality, nanotube diameter, and point defect. The piezoelectric coefficients (e33) of 8-ZBNNT with the VIA-group defects of SN and SeN are estimated to be 18.7 × 10−2 C m−2 and 14.9 × 10−2 C m−2, respectively. The coefficients of defect-mediated 8-ZBNNT are 97% and 57% bigger than that of pristine 8-ZBNNT. The elastic modulus of 8-ZBNNT is decreased due to the VIA-group defects, but is increased for the larger number of unit cells along zigzag rolling direction. The electronic band gap of 8-ZBNNT is reduced due to the VIA-group defects. The large piezoelectricity enhancement of 8-ZBNNT with VIA-group defect is attributable to the ionic contribution. Therefore, the unprecedented defect-mediated 8-ZBNNT provides a new material platform of mechanoelectronic devices for nanoscale sensors and energy conversions.

Off-stoichiometry, structural-polar disorder and piezoelectricity enhancement in pre-MPB lead-free Na0.5Bi0.5TiO3-BaTiO3 piezoceramic

With increasing industrial acceptance of Na0.5Bi0.5TiO3 (NBT)-based lead-free piezoceramics, there is a need to develop insights into the way different factors influence the microstructural–structural–piezoelectric property correlations. In this work, we have examined the role of structural disorder on the piezoelectric response of the pre-MPB composition x = 0.03 of the well-known solid solution series (1-x)Na0.5Bi0.5TiO3-(x)BaTiO3. Using off-stoichiometry on the A-site as a tuning parameter to vary the structural disorder, which we characterize in terms of the fraction of the “cubiclike phase” or variation in the thermal parameter of the A-site cation, it is shown that the piezo response maximizes for the composition, which retains an optimum degree of disorder after poling. Our study confirms the important role of structural disorder in enhancing piezoelectric response in ferroelectric ceramics.

Strain Engineering of Epitaxial Oxide Heterostructures Beyond Substrate Limitations

Epitaxial strain, imparted by an underlying substrate, is a powerful pathway to drive phase transitions and dramatically alter properties in oxide heterostructures, enabling the emergence of new ground states and the enhancement of ferroelectricity, piezoelectricity, superconductivity and ferromagnetism. However, the limitation of commercially available single-crystal substrates and the lack of continuous strain tunability preclude the ability to take full advantage of strain engineering for further exploring novel properties and exhaustively studying fundamental physics in complex oxides. Here we report an approach for imposing continuously tunable, large epitaxial strain in oxide heterostructures beyond substrate limitations by inserting an interface layer through tailoring its gradual strain relaxation. Taking BiFeO3 as a model system, we demonstrate that the introduction of an ultrathin interface layer allows the creation of a desired strain that can induce phase transition and stabilize a new metastable super-tetragonal phase as well as morphotropic phase boundaries overcoming substrate limitations. Furthermore, continuously tunable strain from tension to compression can be generated by precisely adjusting the thickness of the interface layer, leading to the first achievement of continuous O-R-T phase transition in BiFeO3 on a single substrate. This proposed route could be extended to other oxide heterostructures, providing a platform for creating exotic phases and emergent phenomena.

Enhanced piezoelectricity of a PVDF-based nanocomposite utilizing high-yield dispersions of exfoliated few-layer MoS2

Abstract Piezoelectric polymer composite films have attracted extensive attention due to their comprehensive characteristics such as low cost, good flexibility, mechanical property and excellent processability. Among the known polymers, poly (vinylidene fluoride) (PVDF) is an ideal piezoelectric polymer because the β-crystalline form of PVDF has the highest polarization per unit cell. However, initial PVDF mostly suffers from the lack of a β phase, restricting its potential applications. Few-layer MoS2 is predicted to be strongly piezoelectric owing to the opposite orientations of adjacent atomic layers. In this work, we report an efficient approach to enhance the piezoelectric property of PVDF-based nanocomposites by combining few-layer MoS2 with PVDF. The product yield for few-layer MoS2 reached a value as high as 83.3% via a unique liquid-exfoliation technique. For a few-layer MoS2/PVDF composite film with 1 wt.% few-layer MoS2, a high piezoelectric performance enhancement of 360% was achieved compared with the initial PVDF film. In addition, due to the intrinsic lubrication of MoS2, the highest elongation of the piezoelectric composite film was found to be four times higher than that of the pure PVDF film.

Domain structure and evolution in ZnO‐modified Pb(Mg1/3Nb2/3)O3–0.32PbTiO3 ceramics

AbstractThe doping of ZnO is efficient to improve the piezoelectric property and thermal stability of Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT) based ceramics. However, the underlying physics, especially the local domain structures of the ZnO modified PMN–PT ceramics, which is strongly associated with the electric properties, is not clear yet. In this paper, we investigated the local domain structures and their evolution as a function of x in PMN–0.32PT:xZnO ceramics. It was found that, the domain evolution is mainly caused by the growth of grain size induced by the sintering aiding effect of ZnO at x < 0.04, and the domain evolution can be attributed to the phase transition induced by the partial replacement of Mg2+ by Zn2+ in the B‐site of PMN–PT lattice at x > 0.06. Furthermore, we also investigated the domain structure evolution as functions of temperature and local external electric field in PMN–0.32PT:0.06ZnO ceramics, which exhibited superior piezoelectric property relative to other compositions. We found that the irregular nanodomains are more stable at high‐temperature range, and the regular non‐180° domains exhibited more complex rotation behavior under local electric field, which probably leads to the thermal stability and piezoelectric property enhancement in the ZnO‐modified PMN–0.32PT ceramics.