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High-performance piezoelectric materials are essential for diverse electromechanical devices, from actuators to sensors and transducers. Here, we synthesized Ce 2 O 3 -doped Pb(Mg 1/3 Nb 2/3)O 3 -0.29PbTiO 3 (x Ce-PMNT29) solid solutions via conventional solid-state methods. In the x = 2.5 % modified composition, we achieved a notable electrostrain-hysteresis trade-off, enhancing electrostrain (0.2 %), equivalent piezoelectric coefficient d 33 * (1701 pm V–1 at 3 kV cm–1), and reducing strain hysteresis to 8.1 %. Additionally , direct high-temperature piezoelectric characterizations revealed real-time variations in piezoelectric coefficient (d 33) and the actual depolarization temperature, with d 33 reaching 859 pC N−1 at 53 °C and planar electromechanical coupling coefficient (k p) exceeding 70 % within 30−85 °C. Leveraging x-ray diffraction (XRD) and piezoelectric force microscopy (PFM), we elucidated synergistic effects between complex nanodomains and local structural heterogeneity, enhancing piezoelectric activity. This study presents a promising approach for improving electromechanical performance and electrostrain in ferroelectrics, with significant potential for practical piezoelectric applications. [ABSTRACT FROM AUTHOR]

Pb(Mg1/3Nb2/3)O3 (PMN) relaxors have gained a lot of interest due to their unusual dielectric relaxation and high electrostrictive electrostrain. However, the Tm (temperature associated with maximum permittivity) of PMN is lower than room temperature, which limits their future development of electrostrain and practical applications. In this study, we increased the Tm by incorporating a relaxor ferroelectric (FE) end member Pb(Zn1/3Nb2/3)O3 (PZN) rather than a conventional high Curie temperature FE end member to create (1−x)PMN–xPZN solid solutions with x = 0.2–0.5. Their dielectric, FE, and electrostrain properties were systematically investigated. In x = 0.4 composition, we get a maximum electrostrain of 0.134% and an equivalent piezoelectric coefficient d33∗$d_{33}^*$ of 936 pm/V under a rather small driving field of 5 kV/cm. Furthermore, the electrostrain of the x = 0.5 is greater than 0.1% between 20 and 80°C, indicating its possible applicability in precision displacement actuators. Our findings not only clarify the electrostrain and electrostrictive properties of (1 − x)PMN–xPZN system but also show an innovative way to improve electrostrain properties by constructing relaxor–relaxor type solid solutions that can be applied to other FE systems. [ABSTRACT FROM AUTHOR]

Barium titanate (BT) ferroelectric materials have garnered significant interest in pulse dielectric capacitor devices due to their remarkable chemical stability and exceptional electrical performance. However, their inferior energy-storage performance (ESP), characterized by inadequate breakdown strength and high energy storage loss, has hindered their further advancement in applications. To address this challenge, we adopt a synergistic optimization strategy combining composition design with chemical substitution and microstructure engineering through the viscous polymer process (VPP) to develop an eco-friendly system, denoted as (1– x)[0.65BaTiO 3 -0.35(Sr 0.7 Bi 0.2)TiO 3 ]- x Bi(Mg 2/3 Nb 1/3)O 3 (abbreviated as BS- x BMN). This deliberate modification enhances polarization by leveraging the hybridization of the 6 s orbitals of Bi3+ ions with the 2 p orbitals of O2− ions. By adjusting the BMN content to regulate relaxor ferroelectric characteristics and field-induced polarization, we promote the formation of polar nanoregions and microstructural heterogeneity, ultimately enhancing ESP and improving the thermal stability of the materials. In the BS-0.05BMN ceramics fabricated by the VPP, we simultaneously achieve a large recoverable ES density of 5.29 J/cm3 and a prime energy storage efficiency of 95.3% under the E -field of 520 kV/cm, along with reliable temperature applicability within 30−150 °C. These results highlight the potential of BT-based materials for energy storage and provide guidance for future research endeavors. • Synergistic optimization boosts BT capacitor materials, overcoming energy-storage limitations. • Novel BS- x BMN eco-friendly system enhances polarization and microstructure for superior ESP. • VPP fabrication of BS-0.05BMN ceramics yields high energy density and efficiency. • Enhanced thermal stability expands BT-based ceramics' applicability in energy storage. [ABSTRACT FROM AUTHOR]

The synthesis of Bi 0.5 (Na 0.81 K 0.19) 0.5 Ti 1− x Nb x O 3 (BNKT- x Nb) lead-free piezoelectric ceramics via the traditional solid-state method, with varying x from 0.5 % to 4.0 %, is reported. Investigating the influence of Nb5+ ions on dielectric, ferroelectric, and electrostrain properties, alongside assessing the temperature stability of electrical properties, unveiled a notable electrostrain of 0.46 % at room temperature under 80 kV/cm for the 2.0 mol.% Nb5+ doped composition. The incorporation of Nb5+ prompted a transition from the ferroelectric to the relaxor phase, facilitating reversible induction into the ferroelectric phase under an external electric field, leading to the observed large electrostrain. Leveraging the first-order reversal curve (FORC) approach, a detailed analysis of the dynamic response process of different phase structures under the influence of the external electric field was conducted. This analysis elucidated that the continuous polarization response near the boundary of ferroelectric and relaxor phases, induced by the external electric field, primarily drives strain enhancement. These findings underscore the effective modulation of phase structure through Nb5+ doping, offering significant advancements in strain properties. This study opens avenues for the utilization of the material in micro actuators and provides valuable insights for the development of high-performance lead-free piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

Due to requirements for miniaturization and integration of electronic devices, ferroelectric materials with high dielectric permittivity would have potential applications in dielectric capacitors. In this work, (1− x)Pb(Mg 1/3 Nb 2/3)O 3 - x PbTiO 3 (PMN- x PT) powders with x from 0.10 to 0.30 were obtained on the basis of a transitional columbite precursor method, while sintering processes were carried out under three protocols, i.e., (I) 1230 °C for 2 h, (II) 1230 °C for 16 h and (III) 1250 °C for 2 h. The temperature-dependent dielectric properties measured from 25 °C to 225 °C show that, under protocols II and III, the maximum permittivity (ε m) is significantly improved compared to those obtained via protocol I. A maximum ε m of 47036 is obtained in x = 0.25 composition under protocol II, and the ε m is increased by more than 90% at the same composition. In the ceramics sintered through protocols II and III, the characteristics of both dielectric relaxations and dielectric dispersions are also enhanced. In addition, the ferroelectric and piezoelectric properties also show a marked increase in the composition of x = 0.3. Our results suggest that the dielectric and ferroelectric properties of PMN- x PT solid solutions could be effectively enhanced by controlling the sintering protocols. [ABSTRACT FROM AUTHOR]

In this work, we report the dielectric and ferroelectric properties of CuO-doped (1 − x)[0.5573Pb(Mg 1 ∕ 3 Nb 2 ∕ 3 )O3-0.4427PbTiO3]- x Ba(Zn 1 ∕ 3 Nb 2 ∕ 3) O3 (PMNT- x BZN) relaxor ferrielectric ceramic samples with x = 0. 1 7 2 5 , 0.1925, 02125 and 0.2325, which were fabricated by a conventional solid-state reaction method. By introducing the CuO into PMNT- x BZN, the sintering temperature of this system is drastically lowered from 1280∘C to 1120∘C. The second pyrochlore phase, which is often generated during sintering at high temperature, is also inhibited. Meanwhile, broad dielectric peaks with strong dielectric relaxation characteristics are observed from − 1 5 0 ∘ C to 100∘C. Slim and slanted P - E hysteresis loops and purely electrostrictive strains with V-shape are obtained simultaneously in studied compositions from 30∘C to 150∘C. These results suggest that CuO could effectively lower the sintering temperature while maintaining the dielectric and ferroelectric properties of PMNT- x BZN relaxor ferroelectric ceramics. [ABSTRACT FROM AUTHOR]

With its complicated composition architecture, (Bi 0.5 Na 0.5)TiO 3 (BNT)-based relaxor ferroelectrics exhibit distinctive dielectric relaxation phenomena and attractive characteristics. The structural, dielectric, and ferroelectric characteristics of (1– x)(Bi 0.5 Na 0.4 K 0.1)TiO 3 - x (Ba 0.5 Sr 0.5)TiO 3 (BNKT- x BST) solid solutions with x = 0–0.4 were thoroughly examined in this study. The x = 0.1 and 0.2 versions exhibited unexpected ferroelectricity enhancement, and the depolarization temperatures and ferroelectric-relaxor transition temperature were both increased compared to that of the BNKT undoped sample. This enhancement is due to the creation of a tetragonal ferroelectric phase after the introduction of a moderate BST member, according to room temperature and temperature-dependent x-ray diffraction data. The characterization of ferroelectric properties indicated that ferroelectricity was enhanced by increasing the rapidly declining temperatures for the remnant polarization and coercive field, compared to those of the BNKT undoped sample. This discovery contributes to a better understanding of the relationship between the structure and properties of complex relaxor ferroelectrics. A phase diagram of the BNKT- x BST solid solution is also provided, which can be used to guide the search for specific lead-free functional materials for the capacitors, actuators, and transducers based on this eco-friendly system. [ABSTRACT FROM AUTHOR]