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Triboelectric nanogenerator has recently received considerable attention, as it can convert mechanical energy into electrical energy. The NaNbO3–CaSnO3–BaTiO3 (NN–CS–BT) perovskite was synthesized in order to obtain a tribo-material with better performance. It was found that the NN–CS–BT solid solution had been successfully prepared by introducing CS and BT phases into NN. After the sintering process, the NN–CS–BT ceramic showed a dense and fine-grained structure. And the dielectric property of NN–CS-BT was found to enhance significantly compared with that of NN. We additionally investigated the effect of NN–CS–BT particles as fillers on the output performance of polydimethylsiloxane (PDMS) film. The values of output voltage for four samples (PDMS, NN/PDMS, NN–CS/PDMS, and NN–CS–BT/PDMS) were measured approximately 102, 156, 184, and 239 V, respectively. [ABSTRACT FROM AUTHOR]

NaNbO3 (NNO) is one of few Pb-free antiferroelectrics. But it commonly shows ferroelectricity due to the irreversible transition from antiferroelectric to ferroelectric. By adding Sr(Fe0.5Nb0.5)O3 (SFN), a novel dielectric ceramic (1 − x)NNO–xSFN has been prepared by a conventional solid reaction method. The ceramic is the pure phase with x up to 0.15. With increasing x, the polarization–electric relation varies from ferroelectric to antiferroelectric like and then to linear like, indicating that the polarization varies from parallel to antiparallel and then to randomly orientated. The electrical response of the ceramics is further analyzed by the normalizations of impedance and electrical modulus, which suggests enhanced electrical heterogeneity, reduced grain resistance, and decreased thermal activation energy with increasing x. [ABSTRACT FROM AUTHOR]

Using 0.76Bi0.5Na0.5TiO3-0.24SiTiO3 which approaches the morphotropic phase boundary of Bi0.5Na0.5TiO3-SiTiO3 as base composition and adding Bi(Mg2/3Nb1/3)O3, (1-x)(0.76Bi0.5Na0.5TiO3-0.24SiTiO3)-xBi(Mg2/3Nb1/3)O3 dielectric ceramics were prepared by a traditional solid-state reaction method, and their structural, dielectric, and electrical energy storage properties were studied comprehensively. Bi(Mg2/3Nb1/3)O3 disturbs the long-range ferroelectric ordering, thus remanent polarization decreases rapidly. As a result, the electrical energy storage properties improve greatly in the ternary system. [ABSTRACT FROM AUTHOR]

Tetragonal tungsten bronze Ca0.4SrxBa0.6−xNb2O6 (x = 0, 0.1, 0.2, 0.3, 0.4, 0.5) ceramics were prepared by a conventional solid-state reaction method. The structural, dielectric, and ferroelectric properties of these ceramics were investigated. The dielectric response varies from normal ferroelectric to relaxor for x > 0.1 while the polarization–electric field hysteresis loop varies greatly for x > 0.4. The corresponding mechanisms are discussed comprehensively. Moreover, since the A1 sites are fully occupied by Ca in the system, the work discloses the effect of the Sr/Ba ratio at A2 sites on dielectric and ferroelectric properties of tetragonal tungsten bronze oxides. [ABSTRACT FROM AUTHOR]

A hydrothermal-assisted cold sintering process is developed for preparing antiferroelectric NaNbO3 ceramic. The novel process includes hydrothermal synthesizing NaNbO3 particles, cold sintering, and annealing. The physical and electrical properties of the cold sintered ceramics were studied comprehensively and compared with ceramics prepared by conventional sintering techniques. At optimum conditions, dense ceramic can be prepared by the cold sintering process with very low heat treatment temperature, and the properties are comparable with that prepared by conventional sintering. [ABSTRACT FROM AUTHOR]

Recently, it is shown that the thin films of BiFeO3–BaTiO3–SrTiO3 have ultrahigh-energy storage density. However, the energy storage properties of BiFeO3–BaTiO3–SrTiO3 ternary bulk ceramics have not been studied. In this work, the BiFeO3–BaTiO3–SrTiO3 ceramics have been prepared by a conventional solid-state reaction method and the dielectric and electrical energy storage properties have been studied in detail. The ceramic with the composition of 0.25BiFeO3–0.30BaTiO3–0.45SrTiO3 is experimental evidenced to be the best with the highest dielectric permittivity in the ternary system. To suppress the dielectric loss and leakage current, 0.25BiFeO3–0.30BaTiO3–0.45SrTiO3 has been doped with Mn. Mn-doped ceramics have the same perovskite structure but the fine grains are formed and the number of pores decreases. Mn-doping reduces dielectric loss, enlarges the thermally stable zone of the dielectric, and improves the electrical energy storage density simultaneously. 2 mol% Mn-doped 0.25BiFeO3–0.30BaTiO3–0.45SrTiO3 has the most optimized electrical energy storage properties. The energy storage density is 1.33 J/cm3 and the efficiency is 88.5% at 185 kV/cm. The discharge energy density is 2.7 times that of undoped 0.25BiFeO3–0.30BaTiO3–0.45SrTiO3 and 90% stored energy can release in 120 ns. [ABSTRACT FROM AUTHOR]

In the past decades, lead-free ceramics with high polarization, low remnant polarization and high electric breakdown strength have drawn a lot of attention because of their potential applications in dielectric capacitors with excellent energy storage performance. In the current investigation, we develop a novel lead-free Dy doped 0.5Na0.5Bi0.5TiO3–0.5SrTiO3 ceramics, which were fabricated by the conventional electroceramic processing route. By doping Dy2O3 into 0.5Na0.5Bi0.5TiO3–0.5SrTiO3 with various contents from 0.1 at.% to 0.5 at.%, pure perovskite phases and relatively dense structures were obtained. The increase of Dy2O3 concentration not only shifts the Tm toward to lower temperature, but also reduces the permittivity and gain sizes, thus enhancing the temperature stability of dielectric properties. The enhanced dielectric energy storage properties were systematically investigated by testing the polarization–electric field hysteresis loops as a function of the applied electric field, temperature, and loading cycles. The dielectric energy storage density of in 0.1 at.% doped 0.5Na0.5Bi0.5TiO3–0.5SrTiO3 is 1.59 J/cm3, which is nearly twice higher than that of undoped NBT–ST. Hence, the Dy modified 0.5Na0.5Bi0.5TiO3–0.5SrTiO3 ceramics have exhibited potential application as dielectric capacitors with relatively good energy storage performance. [ABSTRACT FROM AUTHOR]

In this investigation, MgO-doped BaTiO3 (BT) ceramics were prepared by a conventional solid-state sintering method. Perovskite-structure was identified by an X-ray diffraction method. Relatively high volume density and relative density were achieved with appropriate MgO contents. With MgO doping, the temperature stability of the dielectric constant of BT samples was drastically improved when the temperature is below their Curie temperatures. It is very interesting that both the energy storage density and breakdown electric field are enhanced by MgO doping compared to that of undoped BT. Particularly, a high energy storage density (Wc) of 0.9 J/cm3 can be achieved at 130 kV/cm with a high energy storage efficiency (η) of 73.3% in 0.25 wt% MgO doped composition. The detailed investigation and analysis can be found in the study. [ABSTRACT FROM AUTHOR]

The ZnFeEuO nanoparticles were prepared with sol-gel method. The effects of sintering temperature on the structural, morphological and magnetic properties were investigated in detail. The results revealed that the ZnFeEuO NPs exhibited weak ferromagnetic properties due to the formation of defects in ZnFeO caused by Eu doping. Moreover, the increased sintering temperature not only enlarged the grain size but also decreased the magnetization of ZnFeEuO NPs due to the decrease of defects in the crystal lattices. [ABSTRACT FROM AUTHOR]

ZnCuVO nanoparticles have been successfully prepared by the sol-gel method and sintered in air at the different temperature. The effects of the annealing temperature on the structural, optical and magnetic properties of the obtained samples were studied. The X-ray diffraction (XRD) results showed that the ZnCuVO nanoparticles was single phase with the ZnO-like wurtzite structure when the annealing temperature was <700 °C. The photoluminescence (PL) spectra revealed that as the annealing temperature increased, the intensity of the UV emission increased and the green emission enhanced significantly. Magnetic measurements indicated that the samples exhibited ferromagnetism at the room temperature. The results of XRD, transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS) revealed that there was no ferromagnetic-related secondary phase in ZnCuVO nanoparticles, the ferromagnetism of the ZnCuVO samples was originated from the fact that the Cu and V ions doped into the ZnO lattice. In addition, the saturation magnetization (Ms) increased with the enhancement of the annealing temperature. [ABSTRACT FROM AUTHOR]