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Piezoelectric actuators play a strong part in the field of electromechanical applications by precisely transferring input electric energy into mechanical force, electric displacement efficiently based on inverse piezoelectric effect. It is still challenging for high-drive electromechanical applications to rely on advanced ferroelectrics with high piezoelectricity. This study focuses on the xPb(Ni1/3Sb2/3)O3–(1 − x)Pb(Zr0.48Ti0.52)O3 ternary ceramics as the base composition to design morphotropic phase boundary region to strengthen piezoelectric response. The results show that the composition at x = 0.12 locates at morphotropic phase boundary (MPB) region which exhibits optimal piezoelectric charge coefficient d33 of 481 pC/N, Curie temperature Tc of 226 °C, and electromechanical coupling coefficient kp = 0.43, respectively. Additionally, this composition demonstrates excellent temperature stability within a range of 160 °C, suggesting its potential as a promising solution for high electromechanical applications. In summary, a comprehensive piezoelectric performance evaluation of the PNS-PZT ternary ceramics was conducted for the first time, yielding the highest piezoelectric coefficient compared with reported peer-reviewed literature. These findings contribute novel perspectives to the compositional design of high-performance piezoelectric actuators. [ABSTRACT FROM AUTHOR]

Piezoelectric materials are widely used in the direction of sensors. PZT-based ceramics are very suitable for precision sensors. However, due to the low Curie temperature, the application temperature range of the material is relatively narrow. Here we show a high-performance material 0.6PZT–0.4PNN. In this case, a morphotropic phase boundary (MPB) region was artificially designed in the 0.6Pb(ZrxTi1−x)O3–0.4Pb(Ni1/3Nb2/3)O3 (x = 0.35–0.41) ceramics to develop high-performance piezoelectric compositions which could cofire with low-cost Ag/Pd inner electrode by 0.2wt% Li2CO3 addition. The ceramic composition at x = 0.39 near MPB possess exceptional properties with high piezoelectric coefficient d33 ∼ 611 pC/N, planar electromechanical coupling coefficient kp ∼ 53.5%, low mechanical quality factor Qm ∼ 64.5 piezoelectric strain of 0.17%, and suitable Curie temperature Tc ∼ 191 °C, respectively. The fact that d33 was detected close to Tc, and no noticeable change below 6.6% in cycling stability was observed at 20 kV/cm means a robust temperature-independence and fatigue reliability of the piezoelectric ceramics. Thus, this research provides a novel high-piezoelectricity configuration with elemental regulation, comparable to the commercial PZTs. [ABSTRACT FROM AUTHOR]

Ba(0.5−1.5x)Sr0.5LaxTiO3(x = 0.005,0.01,0.015,0.02) ceramics were manufactured in N2 atmosphere by solid state reaction method. All ceramic samples present a cubic perovskite phase. The relative dielectric constant of the sample can reach 115,648 at 1000 Hz and 25 °C when x = 0.01, with a dielectric loss of less than 0.04 and a relatively high dielectric temperature stability in a region of 25–250 °C. The same sample experiences a decline in dielectric constant when it is annealed in air. In addition, there is an increase in its dielectric loss, with two sets of dielectric loss peaks. According to the systematic analysis, both the thermal motion of the oxygen vacancy and its defective dipole are responsible for the relaxation behavior. This may serve as a reference for the future study of the dielectric properties of modified materials. [ABSTRACT FROM AUTHOR]

(Ba, Sr)TiO3 ceramic attracts much interest due to its adjustable dielectric performance and outstanding dielectric properties. Alkali-free multi-component glasses with their high dielectric breakdown strength are considered as one of the promising candidates for next-generation high energy density storage capacitor applications. In the present study, oxalate co-precipitation method has been applied to obtain (Ba, Sr)TiO3 nanopowders, which were used to fabricate composite with Ba–B–Al–Si glass and (Ba, Sr)TiO3 ceramic. The parameters, such as the sintering temperature, dielectric constant, and breakdown strength were studied. The results indicated that the sintering temperature and the dielectric constant decreased with increasing the glass content, while the breakdown strength increased firstly and then decreased due to the modification of the microstructure. The effect of different alkali-free glass additions on the sintering temperature and dielectric properties of (Ba, Sr)TiO3 were studied. The composite with 13.5 vol.% Ba–B–Zn glass phase was sintered at 920 °C and showed optimal electrical properties. [ABSTRACT FROM AUTHOR]

Dielectric film capacitors are widely studied in recent years owing to their advanced power density and excellent mechanical and thermal stability. Despite the fact that extensive research has been done, the energy storage density still needs to be further improved. Herein, the highly polarized phase and amorphous phase are introduced into barium zirconate titanate simultaneously by the sol–gel method to fabricate (1−x)BaZr0.2Ti0.8O3−xBi0.5Na0.5TiO3 ((1−x)BZT−xNBT) amorphous films, researching the impact of amorphous phase and NBT levels on microstructure, energy storage, and dielectric properties of the films systematically. This material can generate a giant recoverable energy density of 86.35 J cm−3 and a great energy efficiency of 89.2% when x = 0.10, showing great thermal stability in energy storage property and dielectric property at 20–200 °C and excellent cycling reliability up to 105 cycles, which indicate the potential of 0.9BZT–0.1NBT film in the energy storage field. More importantly, there is no research on BZT-NBT films in the published literatures up to now. This work verifies the feasibility of this system in energy storage films and provides a new avenue to design lead-free dielectric materials. [ABSTRACT FROM AUTHOR]

The requisite for piezoelectric ceramics, which can offer increased sensitivity in harsh environment, is to own high Curie temperature. Here, lead-free 0.75BiFe0.94(Zn1/2Ti1/2)0.06O3-0.25BaTiO3-xmol%MnO2 (BFZT-BT-M) ceramics were selected to develop a novel high temperature piezoelectric composition. Doping of Mn markedly improved comprehensive piezoelectric properties of BFZT-BT-M ceramics at x = 0.25 with the maximum piezoelectric constant d33 of 118 pC/N and high Curie temperature of 503 °C, respectively. The thermal depolarization stability is up to 400 °C. Favorable electrical properties combined with high Curie temperature make the BFZT-BT-M ceramics suitable for high temperature applications. [ABSTRACT FROM AUTHOR]

Sr4Fe6O13 ferrites as a new kind of high frequency microwave absorption materials were synthesized by solid-state method, and its high frequency microwave absorption performances were investigated. The carbon nanotubes (CNTs) were added into Sr4Fe6O13 ferrites to form Sr4Fe6O13/CNTs composites with network structure, which improved the high-frequency dielectric performance and microwave absorption capacity. When the mass ratio of Sr4Fe6O13 and CNTs was 20, the Sr4Fe6O13/CNTs composites achieved the strongest absorption capacity (− 51 dB) at frequency of 15 GHz with 1.2 mm thickness. Those results indicate that Sr4Fe6O13/CNTs composites are suitable potential application to high-frequency communication device in suppressing electromagnetic interference. [ABSTRACT FROM AUTHOR]

Potassium sodium niobate-based ceramics have been extensively studied as high-power energy storage capacitor in recent years due to their excellent dielectric properties. We investigated the microstructure, dielectric-temperature spectrum, and energy storage properties of SiO2-coated 0.9(k0.5Na0.5)NbO3–0.1Bi(Zn2/3Nb1/3)O3 (0.9KNN–0.1BZN) ceramics prepared by solid-state sintering and Stöber method. During the sintering process, SiO2 reacted with 0.9KNN–0.1BZN to form the second phase K3Nb3O6Si2O7. Coating SiO2 could improve the dielectric-temperature stability of 0.9KNN–0.1BZN ceramics, and had excellent performance adapting to high-temperature conditions. When the SiO2 content is 1.0 wt%, the maximum energy storage density of 0.9KNN–0.1BZN ceramics is 0.97 J/cm3, and the breakdown field strength is 200 kV/cm. This work expands the application of (k0.5Na0.5)NbO3 ceramics in the field of energy storage capacitors. [ABSTRACT FROM AUTHOR]

Fe doping has been investigated to determine the effect of defects on the piezoelectric properties of BaTiO3 ceramics. Fe doping can produce oxygen vacancies due to ionic replacement, and then a defect dipole ( Fe Ti ′ - V O · · ) is formed. This acceptor characteristic typically induces a reduced piezoelectric constant but improves the thermal stability and fatigue behavior. A thermally stimulated depolarization current (TSDC) is employed to distinguish the role of defect dipoles from oxygen vacancies and characterize the reasons for fatigue behavior and thermal stability. TSDC of the pure BaTiO3 ceramic shows one peak, whereas Fe-doped ceramic shows two peaks. The first and second peaks are presumably ascribed to defect dipole and space charge polarization, respectively. This study provides an effective method to extensively investigate the effect of defect configuration on ferroelectric–piezoelectric behavior. [ABSTRACT FROM AUTHOR]

Solid-state sintering method was used for the synthesis of Mg1−xCoxSiO3 (x = 0–0.25) ceramics. Phase, microstructure and microwave dielectric properties of the ceramics were investigated. With increase in Co2+ content, the increase was observed in the lattice parameters. The Qufo value of MgSiO3 was enhanced from 103,453 to 145,846 GHz with increasing the value of x content from 0 to 0.15. The Co2+ substitution also led to an obvious decrease in the sintering temperature by ~ 100 °C. Clino-enstatite phase formed for the composition with x = 0 while Proto-enstatite formed as the major along with minor clino-enstatite phase for the compositions with x > 0. Good dielectric properties at microwave frequencies i.e. εr ~ 8.11, Qufo ~ 145,846 GHz and τf ~ − 12 ppm/°C were obtained for the composition with x = 0.15 sintered at 1350 °C for 9 h. This is suggested to be a very favorable dielectric material for millimeterwave applications. [ABSTRACT FROM AUTHOR]

The pure and Sm modified SrTiO3 ceramics have been fabricated by solid state reaction method at different atmospheres, including ambient, reduced and oxidized conditions. All studied ceramics are in single cubic perovskite phase with high bulk density, where Sm doped ceramics possess decreased grain size. The room temperature permittivities of Sr0.97Sm0.02TiO3 and Sr0.98Sm0.02TiO3 sintered in N2 were found to be on the order of 25120 and 13370 at 1 kHz with dielectric loss being 0.044 and 0.008. The giant permittivities were associated with the increase of Ti3+ ions, which were due to the combination of Ti4+ ions and electrons. With increasing Ti3+ ions, the concentration of Ti4+ ions, Ti3+ ions and VO·· reach the balance where the defect dipoles [Ti4+·e-VO··-Ti4+·e] were created, responsible for the low dielectric loss. [ABSTRACT FROM AUTHOR]

Mn-doped barium strontium titanate Ba0.4Sr0.6TiO3-x mol%Mn (x = 0, 1, 3 and 5; BSTMx) thin films were deposited on Pt/Ti/SiO2/Si(100) substrates by spin-coating and annealed at 800 °C. X-ray diffraction patterns revealed that all the thin films were a typical cubic perovskite structure and no impurity peaks were observed. The effect of Mn doping on the ferroelectric properties and energy storage performance of the samples was investigated. The results showed that the recoverable energy storage density Urec and the difference ∆P(Pmax − Pr) between maximum polarization Pmax and remnant polarization Pr firstly increased, then decreased with the increase of Mn doping amount. The optimized energy storage performance was obtained in Pt/BSTM3/Pt thin films: energy storage density of 8.48 J/cm3 and energy storage efficiency of 42.4% at 1.63 MV/cm, electrical resistivity of 4.19 × 1010 Ω cm and leakage current density of 7.77 × 10−6 A/cm2 at 163 kV/cm. Moreover, the effect of different top electrodes on energy storage performance was studied, which displayed that the energy density of Au/BSTM3/Pt films was higher than that of Pt/BSTM3/Pt films. The results indicated that Mn doping and Au electrodes could be effective ways to improve the energy storage properties of BST thin films. [ABSTRACT FROM AUTHOR]

NbO doped 0.8BaTiO-0.2(NaBi)(MgTi)O (0.8BT-0.2NBMT) polycrystalline ceramics were prepared by solid state reaction method. 0.8BT-0.2NBMT samples were observed to possess two dielectric peaks, which were attributed to the formation of core-shell structure (Huang et al. in J Eur Ceram Soc 36:533-540, 2015). Longer sintering induced uniform distributions of the additives. The introduction of NbO into 0.8BT-0.2NBMT could obviously bring about the improvement of the dielectric temperature stability, the degradation of the dielectric loss at room temperature and the decrease of the sintering temperature. The 0.8BT-0.2NBMT ceramics doped with 2.0 at% NbO could satisfy the temperature range of the X9R (−55 to 200 °C, △C/C = ±15% or less) characteristics, with a moderate dielectric constant of 1130, low dielectric loss of 0.7%, low sintering temperature of 1050 °C and insulation resistivity of 5 × 10 Ω cm at room temperature, which might be promising for practical use in multilayer ceramic capacitors. The inhomogeneous distribution and the existence of the secondary phases were responsible for this excellent dielectric temperature characteristic. The complex impedance analysis was introduced to elaborate the conduction mechanism. [ABSTRACT FROM AUTHOR]