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Due to their poor frequency stability and high dielectric loss compared to common energy storage ceramics, bismuth strontium titanate ceramics are rarely employed for energy storage. This paper systematically researches the energy storage characteristics of Sr(1-1.5x)BixTiO3 ceramics. The bismuth strontium titanate ceramics were prepared via the traditional solid phase sintering method. The experiment results indicate that, as x = 0.100, Sr(1-1.5x)BixTiO3 ceramics possess fine frequency stability, high dielectric constant, low dielectric loss, high resistivity, high energy storage efficiency and weak DC electric field dependence of dielectric constant. At 217.6 kV/cm electric field, the energy storage density of Sr(1-1.5x)BixTiO3 ceramic (x = 0.100) reaches 1.63 J/cm3. Therefore, it is a potential dielectric material for energy storage.

(1-x)(Bi0.9La0.1)ScO3-xPbTiO3 (x = 0.47∼0.62, BLS-PT100x) were synthesized by conventional solid-state sintering. A morphotropic phase boundary (MPB) between rhombohedral and tetragonal phases was confirmed by X-ray analysis. The materials show a strong composition dependence on the ferroelectric and piezoelectric properties. The composition near MPB can obtain the optimal electrical properties; however, the electrical properties decay obviously over the boundary. The BLS-PT52 ceramics exhibit the enhanced electrical properties: d 33 = 361 pC/N, k p = 0.40, P r = 24.3 μC/cm2, E c = 1.94 kV/mm and an adjustable broad Curie temperature range from 366 to 467°C. These results show that this composition is a promising candidate for high-temperature piezoelectric materials.

Morphotropic phase boundary (MPB) of (0.8-x)PMT-xPbTiO3(PT)-0.2PbZrO3(PZ) ternary system (x = 0.4) was studied by X-ray diffraction (XRD). It shows that by comparing with 0.4PMT-0.2PZ-0.4PT sample, after doping with Ni, c/a remains almost same (about1.009), while both c and a decrease indicating that lattice shrinks. Content of the tetragonal phase TP% of Ni-doped samples increase up to 81.1% when the doping limit of the nickel is reached (y = 0.05), and the dielectric constant ϵ was found to increase up to 4570 when y = 0.05 and the Curie temperatures of doping samples were found to decrease from 175°C to 157°C.

NaNbO3 platelets were synthesized by the topochemical microcrystal conversion method from platelike precursor particles of layer-structured Bi2.5Na3.5Nb5O18 at 950°C in a molten NaCl-salt. The obtained NaNbO3 platelets remained the shape of precursors with width of 5–10 μm, length of 20–30 μm and thickness of 0.5–1 μm. Textured (K0.5Na0.5)NbO3 ceramics were fabricated by using the NaNbO3 platelets as template in the reactive templated grain growth method. The microstructure and piezoelectric properties of textured (K0.5Na0.5)NbO3-based piezoelectric ceramics were investigated. The textured samples consists of bricklayer-like grains with sizes of 10–20μm and were found to have {001} orientation degree of 69% and higher piezoelectric constant.

In this paper, through control the precursor's structure with layer morphology, the plate-like particles with different edge length and thickness can be syntheszed by the two step molten salt (MSS) method. The results of SEM showed that the NaNbO3 particles were characterized by platelet-like morphology with an edge length of 10∼20 μm and a thickness of 1∼4 μm. The results of XRD indicated the NaNbO3 particles synthesized had a strong orientation in {0 0 l} crystal planes. The plate-like NaNbO3 particles we synthesized are a suitable template candidate to fabricate textured ceramics by TGG or RTGG method, especially to the textured potassium sodium niobate lead-free piezoelectric ceramics.

Ba 0.4 Sr 0.6 TiO 3 (BST) films were deposited on quartz substrates by radio frequency (RF) magnetron sputtering in O 2 /Ar atmosphere. The structural property of the film was studied by XRD, the morphology by AFM and the cross-section by SEM. As-grown films were amorphous and presented compacted grain morphology, its surface fluctuation was about 3 nm. When sputtering time was higher than or equal to 3 h, the annealing temperature above 550°C, the crystalline film has been identified as a cubic perovskite structure. When sputtering time was 5 h, the thickness of film was about 1 μm. Different thickness films could be obtained by controlling the sputtering time.

The compositions of 0.9SrTiO 3 -0.1TiO2 with 0–8wt% Borosilicate glass additive were prepared. The microstructures and dielectric properties of the sintered bodies were studied. It was found a tiny amount of glass additive could lower the sintering temperature of the ceramics, and a very dense microstructure with fine grains was obtained, which resulted in higher dielectric constant and higher breakdown strength (BDS). However, As Borosilicate glass content increased, SrTiO3 had a tendency to react with the glass phase resulting in the productions of SrAl2Si2O8 and TiO2, which had a negative influence on the microstructures of ceramics, consequently degraded the dielectric properties.