33 results about "Strontium barium niobate" patented technology

The invention discloses a method for preparing strontium barium niobate ceramics with high pyroelectric effects.The method includes mixing raw materials BaCO<3>, SrCO<3> and Nb<2>O<5> according to a chemical formula of Sr<x>Ba<1-x>Nb<2>O<6> to obtain Sr<x>Ba<1-x>Nb<2>O<6> powder; sintering the Sr<x>Ba<1-x>Nb<2>O<6> powder by the aid of a spark plasma sintering system in a vacuum environment at the temperature of 1000-1050 DEG C to prepare ceramic sintered bodies and thermally treating the ceramic sintered bodies in the air at the temperature of 965-980 DEG C for 3 hours to obtain the strontium barium niobate ceramics with the high pyroelectric effects.The x can be equal to 0.4 or 0.5 or 0.6.The method has the advantages that the strontium barium niobate ceramics with the high pyroelectric effects have small crystal grain sizes and are high in density, the dielectric breakdown field strength is improved, accordingly, the strontium barium niobate ceramics hopefully can be used for solid-state refrigerating systems, and various currently confronted climatic environmental problems due to the fact that ozone layers are destructed by Freon which is used as a refrigerants can be solved.

In the method, ferroelectric nonocrystal is distributed uniformly in transparent film polymer as ferroelectric material is made from strontium barium niobate, lead zirconate titanate, lanthanum doped lead zirconate titanate, BaTiO3, LiNbO3, or LiTaO3 with nanocrystal particle diameter of 20-80 nm; polymer base material is made from polymethyl methyl acrylate, polycarbonate, polyimide sort and thermoplastic polyamic acid. The prepare process includes polymerizing ferroelectric nanocrystal in the polymer in polymerization procedure of dissolving nanocrystal and polymer in polar solvent and depositing film by soaking or spinning.

The invention discloses an epitaxial barium strontium niobate thin film with a transparent conductive lithium nickel oxide bottom electrode and a preparation method thereof. On one side of the MgO substrate, an LNO thin film, a transparent conductive layer of LNO lithium nickelate, is epitaxially deposited, and then an SBN thin film is epitaxially prepared on the LNO thin film. The preparation steps are as follows: first, using lithium carbonate, nickel oxide, niobium oxide, strontium carbonate, and barium carbonate as raw materials, the lithium nickelate target and the strontium barium niobate target are prepared respectively by solid-state sintering; secondly, the (001) MgO After the substrate is cleaned, put it into the reaction chamber. The reaction chamber is evacuated, and the substrate is heated. Oxygen is used as a protective gas to introduce into the reaction chamber. barium film. The preparation method of the invention is simple, and the obtained barium strontium niobate thin film grows epitaxially in the (001) direction, the thin film has good epitaxy, high quality, large electro-optical coefficient (r33 can reach 180-230pm / V), and has good application prospect.

The present invention provides a glass-ceramic with high dielectric constant. Glass-ceramic, the composition of which contains by weight %: SiO 2 15~30%; SrO 10~18%; BaO15~35%; Nb 2 o 5 20~35%;Na 2 O 0.5~10%; ZrO 2 1 to 5%. The relative permittivity of the glass-ceramic of the present invention is more than 40, has high relative permittivity, can be used for the substrate of the dielectric film in the filter, protective mirror, disk substrate etc.; The present invention solves the problem by optimizing each composition and content Solved the problem of forming hair cream of glass-ceramics with quartz solid solution and barium strontium niobate as the main crystal phase, and the internal quality is uniform, which can be produced efficiently and stably.

The present invention is the preparation process of barium strontium niobate ceramic powder. Niobium oxalate and oxidant barium nitrate and strontium nitrate are mixed and prepared into solution with pure water; proper amount of comburant and organic reductant citric acid, urea, glycine, oxalyl dihydrazine, carbamine, dimethyl hydrazide or hexamethine tetramine are added to obtain precursor solution; the precursor solution is heated to evaporate water and further heated to burn to obtain puffed powder; and the puffed powder is roasted in muffle to obtain the barium strontium niobate ceramic powder. The present invention has simple technological process, simple equipment, short time consumption, low synthesis temperature and molecule level mixing, and the product has high purity, fine grain, homogeneous crystal phase and other features.

The invention relates to a lanthanum oxide doped strontium-barium niobate based glass ceramic energy storage material and a preparation method thereof. The preparation method includes: blending according to a molar ratio of 20BaCO3-20SrCO3-20Nb2O5-33.5SiO2-5Al2O3-1.5B2O3-xLa2O3; after barreling and mixing, drying, and melting at high temperature; quickly pouring high-temperature melt into a copper die for forming; destressing and annealing at certain temperature, cutting into glass sheets, and performing controlled crystallization to obtain the lanthanum oxide doped strontium-barium niobate based glass ceramic energy storage material. Compared with similar materials, the glass ceramic energy storage material has excellent machining performance, and can be mechanically ground and processed into sheets with thickness lower than 80 um, and convenience is brought to subsequent machining of small devices; the glass ceramic energy storage material has excellent dielectric performance and breakdown field strength resistance.

Methods incorporating teachings of the present disclosure may include, for example, selecting a barium strontium titanate (BST) material, where the BST material has a perovskite lattice structure having at least a first lattice constant and a second lattice constant; selecting a strontium barium niobate (SBN) material wherein the SBN material has a lattice structure having at least a third lattice constant and a fourth lattice constant wherein the third lattice constant is substantially equal to the first lattice constant and wherein the fourth lattice constant is substantially equal to the second lattice constant; and growing the SBN material on a grain boundary region of the BST material, where the growing is performed by self-assembly, and wherein the growth is facilitated as the third lattice constant of the SBN material is substantially equal to the first lattice constant and the fourth lattice constant of the SBN material is substantially equal to the second lattice constant. Other embodiments are disclosed.

The invention relates to a strontium barium niobate based glass-ceramic dielectric material and a preparation method thereof. The preparation method comprises the following steps of: with SrCO3, BaCO3, Nb2O5 and H3BO3 as starting raw materials, proportioning according to the mole ratio of aSrO.bBaO.cNb2O5.dB2O3; carrying out ball milling, mixing the raw materials for 8h, and drying; melting at the temperature of 1300 DEG C, and preserving the heat for 30min; then, rapidly cooling and annealing to obtain astomatous uniform glass; carrying out controllable crystallization at a certain temperature to obtain the glass-ceramic dielectric material. The glass-ceramic dielectric material obtained by using the method has the adjustable relative dielectric constant within the range of 21-143, the highest direct current breakdown field strength of 1300kV / cm and the highest energy density of 5.71J / cm<3>.

The invention relates to a strontium barium potassium niobate-based glass ceramic energy storage material, and a preparation method and application thereof. The preparation method specifically comprises the following steps: proportioning raw materials comprising SrCO3, BaCO3, K2CO3, Nb2O5 and SiO2 according to the molar ratio of 25.6mol%[xSrCO3+(1-x)BaCO3]-6.4mol%K2CO3-32mol%Nb2O5-36mol%SiO2, wherein the value range of x is from 0.2 to 1; ball-milling and mixing the materials, drying and melting at high temperature to obtain a high-temperature melt; and pouring the high-temperature melt into a preheated metal mould, performing stress-relief annealing to prepare transparent glass, and cutting the transparent glass into glass sheets; performing controlled crystallization on the glass sheets to obtain the strontium barium potassium niobate-based glass ceramic energy storage material. The strontium barium potassium niobate-based glass ceramic energy storage material is applied to energy storage capacitor materials. Compared with the prior art, the strontium barium potassium niobate-based glass ceramic energy storage material has the advantages that the glass ceramic energy storage material prepared by adding strontium in a barium potassium niobate system has high energy storage density (17.28 J / cm<3>), a uniform and compact microstructure and low tangent value (0.006) of a dielectric loss angle.

A single shot autocorrelator for measuring duration of an ultrashort laser pulse in the far field, having a beam splitter to form two beams from an input ultrashort pulse: the reflected beam is firstly reflected by two mirrors mounted on a translation stage for adjusting time delay and subsequently a third mirror, and after focused by a spherical convex lens, enters a naturally grown strontium barium niobate crystal along the crystal z axis; the transmitted beam is firstly focused by a spherical convex lens, and after reflected by two mirrors, enters the crystal along the crystal z axis from opposite direction. The crystal is in the common focal regions of two spherical convex lenses and generates the transverse second harmonic pulse beam that is the autocorrelation signal to be recorded, which is imaged with an optical microscope onto a charge coupled device camera mounted perpendicular to the beams.