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The increasing demands of device applications in harsh environments have led to higher expectations for temperature and pressure resistance in high-temperature piezoelectric materials. In order to understand the performance characteristics of BiScO3-PbTiO3 (BS-PT) high-temperature piezoelectric materials in practical device applications, this study focuses on analyzing the dielectric, piezoelectric, and ferroelectric properties of BS-64PT ceramics under uniaxial stress up to 150 MPa, as well as its electromechanical performance under a hydrostatic pressure of up to 400 MPa. As the uniaxial pressure increases, both the bias-field and large-signal piezoelectric coefficients exhibit a pattern of initially increasing and subsequently decreasing. Furthermore, the bias-field piezoelectric coefficient exceeds 450 pC/N and the large-signal piezoelectric coefficient surpasses 630 pC/N under uniaxial pressures below 100 MPa. This highlights their exceptional resistance to depolarization caused by uniaxial stress. To obtain more precise piezoelectric properties for BS-64PT ceramics in the 31 and 33 modes under hydrostatic pressure, the admittance fitting method was utilized. This method takes into account the significant losses at higher pressures. Within the pressure range of 0–400 MPa, the values of d33 and d31 for BS-64PT ceramics exhibited a minor change of 7.6% and 8%, respectively. These findings indicate that BS-64PT ceramics exhibit more stable piezoelectric properties under both uniaxial and hydrostatic pressures when compared to the majority of Pb-based perovskite-structured materials. The exceptional stability of piezoelectric properties in BS-PT ceramics can be primarily attributed to their elevated anisotropy energy or coercivity field compared to other perovskite-structured Pb(Mg1/3Nb2/3)O3 (PMN) / Pb(Zr,Ti)O3 (PZT)-based ceramics reported. [ABSTRACT FROM AUTHOR]

[001]-textured 0.4P(Mg1/3Nb2/3)O3-0.25PbZrO3-0.35PbTiO3-0.5%MnO2 (Mn-PMN-PZT) ceramics were fabricated by templated grain growth using 2 vol. % BaTiO3 in this paper. Full matrices of dielectric (ɛij), elastic (sij, cij), and piezoelectric (dij) parameters were obtained by the resonance–antiresonance method. The dielectric constant ɛ33T of textured ceramics reaches 2600, which is four times that of random ceramics. Textured Mn-PMN-PZT ceramics exhibit high d33 = 984 pC/N and high k33 = 0.89, which is much larger than d33 = 223 pC/N and k33 = 0.70 of random ceramics. However, ɛ11T of ceramics decreases by about 30% after texturing, and the corresponding shear coupling coefficient k15 also decreases from 0.66 to 0.44, which may be due to the reduction in the angle between spontaneous polarization and transverse direction. Furthermore, the temperature stability of the textured ceramics was evaluated as well. The phase transition temperature TR−T was determined by the impedance method to be 120 °C. The textured Mn-PMN-PZT ceramic shows high temperature stability, which is better than PMN-PT. [ABSTRACT FROM AUTHOR]

Bismuth layer‐structured ferroelectrics (BLSF) show great potential as piezoelectric materials for high‐temperature applications. In this study, c‐axis/[001]‐textured CaBi4Ti4O15 (CBT) ceramic was synthesized through templated grain growth (TGG) method. A high Lotgering factor (f) of 96% was achieved in textured CBT ceramic using 20 wt% CBT homogeneous template. The piezoelectric coefficient d33 has significantly increased from 7.8 pC/N for random ceramic to 24.3 pC/N for textured ceramic (poled perpendicular to the c‐axis/[001] texture direction), representing an impressive 300% enhancement while maintaining an ultra‐high Curie temperature (TC) of 788°C. In addition, a low dielectric loss (tanδ = 0.4%) and relatively high resistivity (ρ = 1.1 × 1012 Ω·cm) were achieved simultaneously at room temperature. The significant enhancement of d33 in textured CBT ceramic origins from its strong piezoelectric anisotropy. The large d33,T⊥ is due to the nature of polarization switching in CBT (the spontaneous polarization PS of CBT is along a‐axis direction, and the switching of PS is restricted within the a–b plane). Furthermore, the variation of d33,T⊥ remained below 10% across the temperature range of 25–700°C, highlighting the excellent thermal stability of the textured CBT ceramics. These findings suggest that textured CBT ceramic is a promising piezoelectric material for high‐temperature sensor applications. [ABSTRACT FROM AUTHOR]

Design of a projecting‐receiving dual‐purpose transducer is challenging due to the difficulty of synthesizing piezoelectric materials with combinatory "soft" properties (high piezoelectric coefficient d) and "hard" properties (low dielectric loss and high mechanical quality factor Qm). In this study, we provide a different perspective to address this challenge via exploiting single‐crystal‐like electrostriction coefficient Q33 through the fabrication of grain oriented or textured "hard" piezoelectric ceramics. Mn‐doped 0.27Pb(In1/2Nb1/2)O3–0.41Pb(Mg1/3Nb2/3)O3–0.32PbTiO3 (Mn:PIN–PMN–PT) piezoelectric ceramics with a high [0 0 1]c texture fraction of 99% were synthesized, which exhibit three times greater piezoelectric properties (d33 ∼ 828 pC/N) than random counterparts (d33 ∼ 251 pC/N), while maintaining low loss (tan δ ∼ 0.5%, Qm = 443). According to the formula d33=2Q33Prε33${d}_{{\mathrm{33}}}{\mathrm{\ = \ 2}}{Q}_{{\mathrm{33}}}\ {P}_{\mathrm{r}}\ {\varepsilon }_{{\mathrm{33}}}$, the large improvement of d33 in textured ceramics is mainly due to a doubling increase in dielectric constant ε33 and Q33 (∼0.057 m4/C2). Notably, the Q33 exhibits remarkable similarity to that of PMN–PT single crystals, further contributing to the enhanced piezoelectric performance of textured ceramics. Phase field model of ferroelectrics was performed to understand the texturing on Q33 and elucidate the underlying mechanism at the domain level. The textured ceramics exhibit excellent combinatory "soft" and "hard" properties, which are the promising materials for developing projecting‐receiving dual‐purpose transducers with high efficiency and high sensitivity. [ABSTRACT FROM AUTHOR]

[001] textured 0.40BiScO3‐0.60PbTiO3‐0.125 mol%Nb5+ (BS‐60PT‐0.125Nb) high‐temperature piezoelectric ceramics were synthesized using templated grain growth process. A high texture degree F001 of 99% was obtained using 2 vol% BaTiO3 (BT) templates. The piezoelectric charge constant d33 and the unipolar strain under 40 kV cm−1 at room temperature for the textured ceramics are 646 pC N−1 and 0.36%, respectively, which is over two times as those for untextured ceramics (∼243 pC N−1 and 0.17%). The electrostriction Q33 value of the textured sample remarkably increased from 0.034 m4 C−2 to 0.068 m4 C−2 under 30 kV cm−1, showing a twice higher than untextured. Compared with random ceramics, the improvement piezoelectric response of the textured ceramics is primarily attributed to the increase of the dielectric constant εr and electrostriction coefficient Q33 along [001] orientation, which is originating from the anisotropy of piezoelectricity. The BS‐60PT‐0.125Nb textured ceramics have large piezoelectric response and ultrahigh electrostriction with high temperature stability (high depolarization temperature Td of ∼360°C and high Curie temperature Tc of 421°C), showing great potential for the piezoelectric applications at high temperatures. [ABSTRACT FROM AUTHOR]

Liquid phase sintering aids play an important role in facilitating grain growth and promoting texture formation. However, these sintering aids remain at grain boundaries after sintering, leading to a deterioration in the properties and hindering the reproducibility of textured ceramics. In this study, we employed the templated grain growth (TGG) method to synthesize [001]-textured Pb(Mg 1/3 Nb 2/3)O 3 –PbZrO 3 –PbTiO 3 (PMN-PZT) piezoelectric ceramics, and implemented a crucial post-annealing step to remove the residual PbO. The effect of annealing temperatures on the microstructure, dielectric and piezoelectric properties of the textured ceramics was investigated. The results demonstrate the substantial influence of annealing temperature on these properties. Specifically, annealing at 800 °C led to a significant enhancement, with the ε r at room temperature increasing from 2277 to 2410, and the k 33 improving from 0.85 to 0.88. Consequently, the d 33 increases from 1080 to 1220 pC/N. This study emphasizes the effectiveness of the post-annealing treatment in improving the properties and reproducibility of textured piezoelectric ceramics, which is particularly crucial for the mass production of textured ceramics. [ABSTRACT FROM AUTHOR]

Pb(Zr 0.5 Ti 0.5)O 3 (PZT) powders were synthesized from needle-like TiZrO 4 (TZO) precursors by topochemical molten salt synthesis. The effects of the flux types, the raw powder sizes and the synthesis temperatures on the resultant particle morphologies and phase structures of both TZO and PZT were investigated. Via optimizing the synthesis conditions, needle-like TZO with a smooth surface and needle-like PZT with a rough surface were obtained. Transmission electron microscopy (TEM) analyses unveiled that TZO possesses a single-crystal structure with the axial direction along the [010] crystallographic orientation, while PZT exhibits a polycrystalline structure with a discernible degree of misorientation. Notably, the synthesized needle-like PZT from TZO were observed to be unstable and could not induce oriented grain growth of Pb(Mg 1/3 Nb 2/3)O 3 -PbZrO 3 -PbTiO 3 (PMN-PZT) ceramics. This study reveals that improving the thermal stability of needle-like PZT seeds is one of the key factors for the templated grain growth in textured piezoelectric ceramics. • In this study, we used TMSS to synthesize needle-like PZT homogeneous seeds from needle-like TZO precursors. • TEM analyses unveiled that TZO possesses a single-crystal structure with the axial direction along the [001] orientation. • PZT exhibits a polycrystalline structure with a discernible degree of misorientation. • The texture growth of needle-like PZT seeds within PMN-PZT matrix powders was studied. [ABSTRACT FROM AUTHOR]

Na 0.5 Bi 0.5 TiO 3 -BaTiO 3 (NBT-BT)-based lead-free piezoelectric ceramics have been actively studied in recent years as a potential replacement for lead-based materials in ultrasonic applications. However, its relatively low thermal depolarization temperature (T d) is still an imperative obstacle hindering implementation in practical application. Recently, it was reported that quenching is an effective way to improve T d of NBT-based ceramics, but the essential mechanism is still unclear. In this study, 0.94Na 0.5 Bi 0.5 TiO 3 -0.06BaTiO 3 (NBT-6BT) ceramics were quenched in air and liquid nitrogen, and then annealed in oxygen and nitrogen atmospheres to explore the origin of enhanced depolarization temperature. The results from this study correlate the enhancement of T d to the residual stress, which induces a stable rhombohedral ferroelectric phase, thereby increasing the thermal depolarization temperature of NBT-6BT. Our results indicate that the residual stress is also an important factor influencing the electrical properties of quenched piezoelectric ceramics, which should be given more attention in future studies. [ABSTRACT FROM AUTHOR]

In this study, the Pb(Yb 1/2 Nb 1/2)O 3 (PYN) relaxor with high Curie temperature (T C ∼300 °C) was incorporated into PbZrO 3 -PbTiO 3 (PZ-PT) ceramics to form 0.1PYN-(1- x)PZ- x PT ternary ceramics, and their phase compositions were systematically investigated, providing the more detailed phase diagrams, dielectric, piezoelectric, and ferroelectric properties. Excellent piezoelectric performance (d 33 ∼ 450 pC/N, d 33 * ∼714 pm/V), with high coercive field (E C ∼17.5 kV/cm) and T C (∼398 °C) were simultaneously achieved in the 0.1PYN-0.41PZ-0.49PT composition near the morphotropic phase boundary (MPB). The value of d 33 × E C , which exhibits higher than commercial PZT ceramics, indicates its suitability for high-field excitation devices. Additionally, the temperature stability of the resonant frequency (f r) is qualitatively studied by analyzing the main factors influencing f r from a theoretical perspective. Superior stability is achieved in the 0.1PYN-0.38PZ-0.52PT composition (T C ∼ 405 °C) with tetragonal phase, and the temperature coefficient of resonant frequency (Δ f r / f r 25 °C) remains within 0.5% up to 300 °C, far outperformance than previous reports. [ABSTRACT FROM AUTHOR]

The search for a suitable donor dopant to improve the piezoelectric response of BiScO 3 -PbTiO 3 (BS-PT) piezoelectric ceramics without sacrificing temperature stability is crucial for developing high-temperature piezoelectric materials for the application in the elevated temperature. In this study, the effects of Sb5+ donor doping on the microstructure, dielectric, ferroelectric, piezoelectric and electromechanical properties of the BS-PT ceramics were investigated. It was found that the Sb5+ dopant acts as the grain growth inhibitor, resulting in a dense and fine-grain microstructure. An enhanced piezoelectric properties d 33 of 535 pC N−1 with a high T c of 440 °C was simultaneously achieved in 0.25 mol%Sb5+ doped BS-PT (BSPT-0.25Sb) ceramic. The results of in-situ piezoelectric constants and electromechanical coupling coefficients as a function of temperature indicate that the BSPT-0.25Sb ceramic has a high depolarization temperature T d of 400 °C, which is much higher than those of the most widely used PZT-based piezoelectric ceramics. Furthermore, BSPT-0.25Sb ceramic has much higher resistivity and lower dielectric loss than PZT-4 and PZT-8 at high temperature. The excellent piezoelectric properties and thermal stability of the BSPT-0.25Sb ceramic indicate that it is a promising piezoelectric material for high-temperature applications. [ABSTRACT FROM AUTHOR]

Na 0.5 Bi 0.5 TiO 3 -based solid solutions are one of the most promising lead-free piezoelectric candidates since they can be easily tailored to exhibit large electrostrain. However, the large hysteresis and temperature-dependence of the electrostrain response are longstanding obstacles for their practical applications. In the present study, 0–3 type composites were developed with 0.97(0.94Na 0.5 Bi 0.5 TiO 3 -0.06BaTiO 3)-0.03AgNbO 3 (NBT-6BT-3AN) matrix phase and ZnO inclusions. The optimum addition of 5 wt.% ZnO in the composites leads to reduction in hysteresis of electrostrain by 35% in comparison with pure NBT-6BT-3AN at room temperature. Meanwhile, electrostrain of the composites maintains superior temperature stability, with a variance of less than ±10% in the temperature range between 25 and 125 °C. The reason for the improvement of electrostrain is proposed to be attributed to the ergodic/nonergodic mixture phases induced by residual stress between the inclusion and matrix, as well as the phase evolution caused by the incorporation of Zn2+ into the matrix. Therefore, this work provides a new strategy to improve the electromechanical properties of Na 0.5 Bi 0.5 TiO 3 -based ceramics. [ABSTRACT FROM AUTHOR]