46results about How to "Ferroelectric" patented technology

The invention discloses a potassium-sodium niobate based oxide up-conversion luminescent material with a chemical formula of (Na0.5+sigmaK0.5-yAy)1-x-zMxYbzNbO3:Phi C or (Na0.5-yAyK0.5+sigma)1-x-zMxYbzNbO3: Ph iC, wherein M is selected from one or more of Li, Na, K, Tl and Ag; C is selected from one or more of Li, Na, K, Tl and Ag; A is one or more of K, Na and Li; a value range of x is not smaller than 0.00001 and not bigger than 0.15, the value range of y is not smaller than 0 and not bigger than 0.5, the value range of z is not smaller than 0 and not bigger than 0.35, the value range of sigma is not smaller than 0 and not bigger than 0.1 and the value range of Phi is not smaller than 0 and not bigger than 0.1. The luminescent material disclosed by the invention further has up-conversion luminescent characteristic in addition to piezoelectric performances, ferroelectric performances and dielectric performances, belongs to photoelectric multifunctional materials, and not only can be applied to the piezoelectric field, but also can be applied to the sensor field, the information storage field, the biological detection field and the biomedical field.

The invention provides a preparation method for a BiFeO3 target material. The preparation method for the BiFeO3 target material comprises the following steps: carrying out grinding, ball milling, preburning, re-ball milling, granulation and screening for the mixture of bismuth oxide Bi2O3 and ferric oxide Fe2O3 to obtain the target material; and then carrying out batch dropping, baking, heating with pressure, heat insulation and cooling for the target material. The invention also provides a method for preparing a film through the BiFeO3 target material. The method comprises the following steps: selecting a Pt/TiO2/SiO2/p-Si substrate; preparing the BiFeO3 film through a radio frequency magnetron sputtering method; and finally carrying out the annealing treatment of the prepared BiFeO3 film. The target material has the advantages of no impurity phase, levelness and compactness. The film prepared through the target material has a compact and even surface, better crystallinity, no impurity phase, low drain current, saturated electric hysteresis loop, good fatigue characteristic, and good repeatability.

The invention relates to a blue-excited red fluorescent material and a preparation method thereof, belonging to the field of luminescent materials. The blue-excited red fluorescent material has the following chemical expression: Ca1+d-x-mAmRxBi2Ta2-nBnO9:fC, wherein the R is selected from one or more rare earth elements of Pr, Sm, Eu and Lu; the A is selected from one or more than one of Sr, Ba, Mg, Zn and Cu; the B is selected from one or two of Nb and V; the S is selected from one or more than one of Li, Na, K, Ti, Ag, B, Al, Ga and In, the x is not less than 0.00001 and is not more than 0.1; the m is not less than 0 and is more than 0.99; the n is not less than 0 and is not more than 1.99; the d is not less than 0 and is not more than 0.1; and the f is not less than 0 and is not more than 0.1. The blue-excited red fluorescent material not only has the properties of piezoelectricity, ferroelectricity and dielectricity, but also has the characteristic of blue-excited red emission, belongs to a photoelectric multifunctional material and can be widely applied to the fields of white light LED (Light Emitting Diode), optoelectronic integration, micro electromechanics, photoelectric sense, and the like.

The invention relates to a novel blue-light-excited red fluorescent material applied to a white light LED (Light Emitting Diode) technology and a preparation method thereof, belonging to the field of light-emitting materials. The blue-light-excited red fluorescent material has a general formula of Bi0.5+dNa0.5-yAy)1-xRxTiO3:fC, wherein R is selected from one or more than one of rare-earth elements Pr, Sm, Eu and Lu, A is selected from one or more than one of the same group of univalent elements K and Li, C is selected from one or more than one of Li, Na, K, Tl and Ag, 0.001<=x<=0.1, 0<=y<=0.5, 0<=d<=0.1, and 0<=f<=0.1. Blue-light-excited red fluorescent powder provided by the invention has good stability, is not easy to deliquesce, does not need cladding treatment, not only has piezoelectric, ferroelectric and dielectric properties, but also has the characteristic of exciting red light by blue light, belongs to a multifunctional photoelectric material, and can be widely applied to fields such as white light LEDs, photoelectricity integration, micro electro mechanical systems, photoelectricity sensors and the like.

The invention provides a single-phase oxide multiferroic ceramic with exchange bias effect. The single-phase oxide multiferroic ceramic is as shown in the formula (I): Bi10Fe5.9Co0.1Ti3O30 (I). The single-phase oxide multiferroic ceramic has high Curie temperature, has ferroelectricity and ferromagnetism under the room temperature at the same time, and has intrinsic exchange bias effect. Not only a magnetic field can be regulated and controlled, but also an electric field can be regulated and controlled, the possibility of encoding storage information through the adoption of electric polarization and magnetic polarization at the same is provided, and then a magneto-electric mutual-control nonvolatile storage magnetic medium with ultrahigh storage density becomes possible.

The invention relates to a ferro-electricity film capacitor of ferro-electricity and relative preparation, wherein said film capacitor is formed by silicon substrate, silica dioxide baffle layer, titania adhesive layer, low electrode metal layer, low buffer layer, ferro-electricity film layer, up buffer layer, and up electrode metal layer; the adhesive layer is 10-30nm thick; the low electrode metal layer is 100nm-300nm; the low buffer layer is 5-20nm thick; the ferro-electricity is 200-500nm thick; the up buffer layer is 100-200nm thick; the up electrode metal layer is 80-150nm thick. The inventive capacitor has low fatigue speed, low drain current. The invention uses magnetic control splash method to layer-to-layer splash production, while the product has better property, with single direction.

The invention discloses a two-dimensional semiconductor material negative capacitance field effect transistor and a preparation method thereof; a two-dimensional alloy semiconductor material HfZrSe2 is adopted as a channel material, and the surface of the channel material is oxidized in air to generate HfZrO2, and then annealing is carried out to obtain an HfZrO2 dielectric layer with a ferroelectric property; a high-k gate dielectric layer is deposited on the dielectric layer, and a gate dielectric with a mixed structure is formed. By means of the device structure, high gate dielectric and channel two-dimensional semiconductor material interfaces can be obtained, the deterioration of the interface state on the sub-threshold characteristic is reduced, and the super-steep sub-threshold slope is easily obtained; meanwhile, the high-k gate dielectric on the upper layer can protect the HfZrO2 dielectric of the ferroelectric characteristics below, so that the dielectric is isolated from theair, and the stability of the device is greatly improved. The device is simple in preparation process and large-scale production can be realized.

The invention takes analytically pure PbO, Bi2O3, NiO and TiO2 as raw materials, solid phase method is adopted to synthesize (1-x)PbTiO3-xBi(Ni1/2Ti1/2)O3, x is more than or equal to 0.0 and less than or equal to 0.6, PbO, Bi2O3, NiO and TiO2 are calculated and weighed by target x value, the weighed samples are subject to ball milling for 24 hours in ethanol solution, thus the samples are mixed fully, the dried powder is subject to heat preservation at 800-900 DEG C for 3-5 hours, is pressed into pieces after being subject to temperature reduction and cooling and then is subject to heat preservation at 1100-1200 DEG C for 3-12 hours, and cooling is carried out, thus obtaining zero expanding material (1-x)PbTiO3-xBi(Ni1/2Ti1/2)O3 with multiferric high mechanical properties. The material has zero expanding characteristic at the temperature range of 25-525 DEG C, ferroelectric property, ferromagnetism and high mechanical properties; and preparation technology is simple, and equipment requirement is lower.

The invention belongs to the field of inorganic nonmetal functional ceramic powder materials, and particularly relates to a method for realizing synthesis and sintering integration of a metastable-state mixed-valence rare earth iron-based oxide ceramic material through a sintering technology for triggering synchronous reaction of a precursor by using pressure and discharge breakdown under a metastable-state or unbalanced condition. Through cooperative regulation and control of applied current and pressure, and in combination with sintering mold design, sintering time control and precursor character control, accurate regulation and control of nucleation and growth characteristics of the metastable phase material system can be realized, and the physical properties of the synthesized ceramic material are further regulated and controlled. The prepared block material has the temperature-induced charge ordered transition characteristic, multiferroic property, thermistor characteristic and piezoresistor characteristic; the material has considerable application value in preparation of functional electronic devices, sensors, thermistors, magnetic sensing devices and the like.

The invention relates to a single-phase multiferroic ceramic material and a preparation method of the single-phase multiferroic ceramic material. The material and the method aim at solving the technical problem of week ferromagnetism of the conventional single-phase multiferroic material bismuth ferrite. A chemical expression of the single-phase multiferroic ceramic material is (1-x)Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)(Fe0.5Ta0.5)O3, wherein x is equal to 0.2-0.4. The preparation method comprises the steps of performing wet ball-milling on barium carbonate powder, calcium carbonate powder, titanium dioxide powder, ferric oxide powder, tantalum pentoxide powder and zirconium dioxide powder after mixing, putting in a pipe furnace for presintering after drying, then performing the wet ball-milling again, after drying, adding an adhesive agent, pressing into a prefabricated body, and sintering the prefabricated body in the pipe furnace, so as to obtain the single-phase multiferroic ceramic material. The single-phase multiferroic ceramic material is in a tetragonal phase perovskite structure at a room temperature, has ferromagnetism and ferroelectricity simultaneously and can be used for the fields of electricity and electronics.

The invention discloses a preparation method for substituting fluorine for oxygen in bismuth ferrite crystal lattices. The method comprises the following steps of: 1, selecting a utensil made of anticorrosive material as a container, selecting diluted acid as a solvent, weighing nitride of Bi and nitride of Fe in a stoichiometric ratio, adding the nitrides into the solvent in a molar ratio of 1:1, preparing a proper amount of fluorine-containing salt, and adding citric acid into the solution; 2, performing initial reaction on the prepared solution in a water bath for (2.5+/-0.5) hours with uniform stirring, and drying the reaction product in an oven to obtain powder; and 3, performing decomposition reaction on the obtained powder at the high temperature of 780+/-15 DEG C for 30+/-3 minutes, removing impurities, sheeting the decomposed powder, sintering the powder at the high temperature of 810+/-15 DEG C for 10+/-2 minutes, and thus obtaining a sample in which F-1 effectively enters BFO crystal lattices. The sample in which the fluorine effectively enters the bismuth ferrite crystal lattices and substitutes the oxygen has ferro-electricity and ferromagnetism, and the other path isprovided for realizing the development of multifunctional electronic devices.

The invention discloses a high temperature-resisting multiferroic aluminum nitride film and a preparation method thereof. The molecular formula of the material is Alx(AyB1-y)1-xNz,wherein, x represents the molar fraction of Al, and the value of x is in a range of 0.85-0.95; and the value of y is in a range of 0.45-0.8. Aluminum nitride prepared with the method has both ferroelectric and ferromagnetic characteristics, and the Curie temperature of thealuminum nitridewithferroelectric and ferromagnetic characteristicsreaches 450 DEG C, so that magnetism can be modulated through an electric field, and ferroelectricity can also be regulated through a magnetic field.

The invention discloses a single-phase multiferroic ceramic material and a preparation method thereof, relates to a multiferroic ceramic material and a preparation method thereof, and aims to solve a technical problem of weak magnetic property of the conventional single-phase multiferroic material bismuth ferrite. The single-phase multiferroic ceramic material provided by the invention has a chemical formula of Ba0.7Ca0.3FeTaO3; the preparation method comprises the following steps: mixing barium carbonate, calcium carbonate, iron trioxide and tantalum pentoxide powder; then, wet ball-milling; drying and then placing in a tubular furnace for pre-burning; then, wet ball-milling; drying and then adding a binder for being pressed into a preform; then, sintering the preform in the tubular furnace to obtain the single-phase multiferroic ceramic material. The single-phase multiferroic ceramic material has a tetragonal structure at room temperature, also has ferromagnetism and ferroelectricity, and can be applied to electrical and electronic fields.

The invention provides a liquid crystal modified epoxy resin adhesive with a conductive switching performance and a preparation method thereof. The liquid crystal modified epoxy resin adhesive is prepared from rod-like liquid crystal molecules having a bending angle of 100-150 degrees, toluene diisocynate oligomer liquid crystal modifier and polyurethane modified epoxy resin. The preparation method comprises the following steps: adding bend-shaped liquid crystal oligomer into isopropyl alcohol of epichlorohydrin, heating and stirring; adding polyurethane prepolymer, dropwise adding 2-ethyl-4-methylimidazole and methyl tetrahydrophthalic anhydride, shearing and stirring at high speed; heating to react, filtering, washing, precipitating and drying to obtain bend-shaped liquid crystal polyurethane modified epoxy resin; adding the bend-shaped polyurethane modified liquid crystal liquid epoxy resin, an activated carbon material and a curing agent DDS into a solvent, dissolving, and performing rotary evaporation to remove the solvent to obtain the liquid crystal modified epoxy resin adhesive with conductive switching performance. The adhesive has excellent conductivity and mechanical performance.

The invention relates to a multiferroic compound and a preparation method thereof. The multiferroic compound is characterized by adopting the molecular formula of [C6H5(C2H2)4NH3]2[CuCl4], adopting a layered perovskite-like structure, and belonging to a tetragonal system at 350 K, and monoclinic systems at 293 K and 120 K, wherein the space group of the tetragonal system at 350 K is P4/mbm, and the cell parameters a, b, c and V of the tetragonal system at 350 K are 7.4531(4) angstrom, 7.4531(4) angstrom, 23.317(2) angstrom, and 1295.2(2) angstrom<3> respectively; the space group of the monoclinic system at 293 K is P2(1)/a, and the cell parameters a, b, c, beta and V of the monoclinic system at 293 K are 7.2620(5) angstrom, 7.4725(6) angstrom,23.282(2) angstrom, 91.999(2) degrees, and 1262.6(2) angstrom<3> respectively; the space group of the monoclinic system at 120 K is P2(1), and the cell parameters a, b, c, beta and V of the monoclinic system at 120 K are 27.663(1) angstrom, 7.4916(5) angstrom, 29.423(2) angstrom, 101.819(2) degrees, and 5968.3(6) angstrom<3> respectively. The multiferroic compound provided by the invention has three basic ferric properties of ferroelasticity, ferroelectricity and ferromagnetism at the same time, and has the advantages that ferroelastic phase transition occurs at a temperature higher than the room temperature; magnetic bistable state occurs during ferroelectric phase transition or ferroelastic phase transition.

The invention discloses an organic-inorganic hybrid molecular ferroelectric material which is of a crystal structure, the molecular general formula of the crystal is [CPA] 2CuBr4 (CPA = cyclopentylamine cation), an asymmetric unit is composed of two [CPA] < + > cations and a distorted [CuBr4] < 2-> anion, the crystal belongs to a monoclinic system Pna21 space group at the room temperature of 293 K, and is crystallized in a Pnma space group of an orthorhombic system at the room temperature of 395 K, the Curie temperature 393K exceeds that of most molecular ferroelectric, and the Curie temperature 393K can be comparable with that of a commercial ferroelectric BaTiO3 (393K); the crystal is prepared by adopting a solution volatilization method, the process is simple, the repeatability is high, and the crystal structure is stable. The molecular ferroelectric material shows excellent reversible dielectric properties and ferroelectricity, and can be applied to the fields of information storage, solar energy storage, sensors, variable capacitors, intelligent switches and the like.

The invention discloses a diisopropyl propylamine tetrafluoroborate crystal material as well as a preparation method and application thereof, and belongs to the field of organic and inorganic hybrid materials. The crystal material is crystallized in a Pna21 ferroelectric space group at room temperature and has two times of reversible phase change near 323.5K and 404K, and the heat absorption capacities measured by differential calorimetric scanning are 40.375 J/g and 11.014 J/g respectively. In addition, the crystal structure is simple in preparation process, has good thermal stability and hydrophilic and oleophylic properties, can be produced on a large scale, and can be used as an amphiphilic room-temperature ferroelectric material with low cost and a clear structure.