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To fully understand how irradiation affects the structural, optical, dielectric, and ferroelectric characteristics of BSmT ceramics, a systematic study is needed. The characteristics of BSmT ceramics were minimally affected by different gamma doses, and they demonstrated high stability against gamma irradiation, which offers considerable promise for their use in nuclear reactor technology.

This work employs the conventional solid-state reaction method to synthesize Ba0.92La0.08Ti0.95Mg0.05O3 (BLMT5) ceramics. The goal is to investigate how defect dipoles affect the ability of lead-free ferroelectric ceramics made from BaTiO3 to store energy. An extensive examination was performed on the crystal structure, dielectric properties, and energy storage capacity. The analysis found that the polarization hysteresis loops of BLMT5 ceramics had a significant maximum Pm of around 30 µC/cm3 and a low remanent polarization Pr of around 1.80 µC/cm3. In an electric field of 147 kV/cm, defect dipoles significantly increased the recovered energy density, reaching about 1.55 J/cm3. This also increased energy efficiency by over 91%. Furthermore, the BLMT demonstrates exceptional suitability for thermal stability since its performance remained unaffected at the temperatures under examination. The findings of this research indicate that these materials have great potential as suitable contenders for high-power energy storage applications. [ABSTRACT FROM AUTHOR]

There is an immediate demand for eco-friendly, high-performance, and highly stable energy storage materials for pulse power systems. Ceramics based on SrTiO3 have a high breakdown strength (BDS) and dielectric constant. In this work, we fabricated a polycrystalline of Sr(1-x)(Nd, Li)xTiO3 ceramics via microwave-assisted heating of the starting materials. X-ray diffraction analysis reveals a pure perovskite phase without any secondary phase. Scanning electron microscopy images exhibit dense grain morphology with a decrease in grain size as the dopant concentration increases. The frequency dependences of the dielectric properties were studied in the frequency range of 100 Hz-1 MHz at room temperature. The polarization-electric field hysteresis loops were examined to ascertain the effect of co-doping on the energy-storage capability of SrTiO3 ceramics. After increasing the co-dopants from 0 to 8%, the energy density increased nine times (from 0.11 J/cm3 to 0.952 J/cm3), and the energy storage efficiency increased from 80.71% to 95.98%, respectively. In addition, the samples demonstrate excellent thermal stability, and their energy storage properties are stable up to 80°C. We may infer from this discovery that the bulk Nd3+ and Li+ co-doped SrTiO3 materials are good candidates for high-energy-density capacitor applications. [ABSTRACT FROM AUTHOR]

X-ray absorption spectroscopy and x-ray diffraction experiments are carried out to probe the short- and long-range order in lanthanum-modified PbTiO3 ceramic materials for x ranging from 0 to 30 atom percent of La. the analysis of extended X-ray absorption fine structure spectra shows a decrease in the local disorder around Ti atoms as the content of La increases.

The substitution of rare-earth ions has been recognized as an effective way to modify the multiferroic properties, especially to realize the electric field-controlled magnetism in BiFeO3 ceramics, in which the symmetry modulation of R3c/Pna21 and the unlocked ferromagnetism through breaking the cycloidal spin structure are the key issues. Here, the enhancement of ferroelectric polarization and weak ferromagnetism are investigated in Bi1−xLaxFeO3 ceramics together with the magnetoelectric coupling coefficient αME with the development of the Pna21 phase. The expected electric field-controlled magnetism is achieved at the phase boundary through the electric field-induced transition of Pna21/R3c, where the variation of magnetization reaches 34.18 emu/mol (58.95%) at x = 0.18 after poling. [ABSTRACT FROM AUTHOR]

We investigated the densification and electric conductivity in uncommon ultra-fine-grained anatase TiO2 nanoceramics. These materials were prepared by Spark Plasma Sintering (SPS) at 850 °C and exhibited a relative density of 95% and mean grain size of 57 nm. The structural TiO2 anatase phase and microstructural characteristics were determined by XRD and SEM analyses, respectively. A main densification mechanism was proposed based on the grain size–relative density relationship, where an effective pinning effect of nanopores on agglomerates was suggested. Measurements of electric impedance and modulus revealed the influence of SPS conditions on electrical properties. The conductivity relaxation and activation energy in such dense anatase TiO2 nanoceramics were also examined. [ABSTRACT FROM AUTHOR]

A dynamic model is proposed for ferroelectrics. The mathematical model is a system of nonlinear differential equations that results from considered dipole-dipole and dipole external field interaction for each dipole. All the simulations are carried out integrating numerically the system of ordinary differential equations for a plane dipole arrangement. On simulation of relaxation of polarization in time domain a potential law is found, in good agreement with experimental evidence. The influence of several parameters in system response is discussed. Finally, hysteresis loop was obtained and shows noise behavior. [ABSTRACT FROM AUTHOR]

The structural and spectroscopic characterization of transparent lead lanthanum zirconate titanate ceramics doped with Nd(super 3+) , Er(super 3+) , or Yb(super 3+) ions, is presented. The results indicate the potential of these polycrystalline host-ion combinations for the construction of diode-pumped lasers in the near-infrared region.

Features of the diffuse phase transition in lead barium niobate (Pb(sub x)Ba(sub 1-x)Nb(sub 2)O(sub 6)-PBN) ferroelectric ceramics are discussed. The phase transition diffuseness decreases with the increase of the Pb(super 2)+ content when the Pb/Ba ratio gets closer to the morphotropic phase boundary.