313results about "From melt solutions" patented technology

The invention discloses a series of alkali metal borate compounds and alkali metal borate crystals as well as a preparation method and application thereof, and belongs to the technical field of photoelectric functional crystal materials. The chemical general formula of the series of compounds and crystals thereof is A3RE (B3O6) 2, wherein A is K, Rb, Cs or NH4; rE = Sc and Y, the molecular weight is 355.93-744.48, the series of crystals belong to a trigonal system, the space group is P321, the cell parameters a = b = 10.5237 (13)-135237 (13), and # imgabs0 # Z = 3. The series of alkali metal borate compounds are synthesized by adopting a solid-phase reaction method or a hydrothermal method, and the series of crystals grow by adopting a high-temperature melt method or a hydrothermal method or a solution method. The series of materials can be used for manufacturing second harmonic generators, upper and lower frequency converters, optical parametric oscillators, polarizing prisms and the like.

The present application provides a high-nickel single-crystal cathode material, a preparation method thereof, a cathode electrode sheet, a secondary battery, and an electrical device. The chemical formula of the high-nickel single-crystal cathode material is Li 1+δ Ni x M y Q 1‑x‑y O 2+ε A α R β X γ , 0.8 ≤ x < 1, 0 < y ≤ 0.2, 0 ≤ δ ≤ 0.15, 0 < ε ≤ 0.2, 0 < α ≤ 0.04, 0 < β ≤ 0.04, 0 ≤ γ ≤ 0.04. The M element and the Q element each independently include one or more of Mn, Co, Al, Ta, Ti, Nb, Ge, Y, Nb, W, Zr, Ce, Ca, Sr, Sc, V, Cr, and Mo; the A element includes one or more of Mg, Ca, Sr, Ba, Ti, Zr, V, Nb, Ta, Mo, W, La, Ce, Sc, and Cr; the R element includes one or more of B and P; the X element includes one or more of Na, K, Mn, Mg, Ca, Sr, and Al; the molar ratio of Ni 3+ on the surface of the high-nickel single-crystal cathode material is 38% - 55%, and the molar ratio of lattice oxygen on the surface is 7% - 15%. The structural defects of the material are significantly reduced, thereby improving its specific capacity and enhancing its cycling performance.

The invention discloses a low-resistance N-type gallium oxide crystal and a growth method thereof. The growth method comprises the following steps: pretreatment of raw materials: sintering a doped gallium oxide material block formed by mixing gallium oxide powder and doped raw material powder; crystal growth: heating the iraurita crucible to melt the doped gallium oxide material block, increasing the power of the medium-frequency induction coil to raise the temperature of the gallium oxide melt, keeping the temperature, cooling to the melting point of gallium oxide, keeping the melt state, firstly reducing the power of the medium-frequency induction coil to spontaneously nucleate at the cold core of the upper surface of the melt and realize the transverse growth of the nucleated crystal; reducing the power of the lower medium-frequency induction coil to enable the gallium oxide melt to grow from top to bottom until the gallium oxide melt completely grows into crystals; after crystal growth is finished, the temperature is reduced to 1200-1400 DEG C, heat preservation is conducted, cooling is conducted to the room temperature, and the low-resistance N-type gallium oxide crystals are obtained.The growth method is simple in process, the crystal growth speed is conveniently controlled, the crystal forming rate is increased, and large-scale mass production is achieved.

The invention discloses a low ferromagnetic resonance linewidth BaFe12O19 single crystal and a preparation method thereof, and belongs to the technical field of magnet materials. According to the method, growth of the BaFe12O19 single crystal is realized mainly through multiple times of temperature rising and falling and multiple times of temperature oscillation. Compared with direct cooling, the single crystal grown by the method provided by the invention has higher Curie temperature and saturation magnetization and narrower ferromagnetic resonance line width. Through collaborative optimization of high Curie temperature, high saturation magnetization and low ferromagnetic resonance line width, the BaFe12O19 single crystal can be better applied to the frontier fields of high-frequency electronic devices, high-temperature permanent magnet systems, quantum technologies and the like. The improvement of the performance of the device can promote the development of the device in the directions of high frequency, miniaturization and high energy efficiency, and has strategic significance for new-generation communication, energy and information technologies.

The invention discloses an Mg / Nb / Al co-doped and coated single crystal LiNi0. 9Mn0. 1O2 positive electrode material, and the cycling stability is obviously enhanced. The formed high-entropy layer enables lattice oxygen to be highly reversible, precipitation and release of oxygen are effectively inhibited, formation of oxygen vacancies is slowed down, and transition metal ions are anchored. In the lithium removal / intercalation process, reversibility of H2-H3 phase change is improved, crystal face slippage is relieved, accumulation and release of anisotropic lattice strain are relieved, and Li < + > dynamic diffusion is promoted. Meanwhile, an Al2O3 / LiAlO2 interface formed on the surface induces formation of thin and stable CEI, HF attack and dissolution of metal ions are improved, and the material has rapid charging and discharging capacity and high-voltage stability. Therefore, the high-entropy single-crystal positive electrode material plays a crucial role in effectively improving the rate capability and the cycling stability of the ultrahigh-nickel cobalt-free negative electrode material.

The invention discloses a method for preparing hexagonal boron nitride by adding seed crystals, and relates to the field of boron nitride materials, the hexagonal boron nitride with two scales of nanoscale and micron scale is prepared at a relatively low temperature of 1100-1600 DEG C by adopting a molten salt method and adding the seed crystals, and the method has important significance for producing high-quality h-BN single crystals with different sizes. The operation difficulty is low, the energy consumption is low, the cost is saved, and large-scale production is easy.

The invention provides a crystal pulling method for reducing the head resistivity of a heavily arsenic-doped silicon single crystal, and belongs to the technical field of doped silicon single crystal production. Comprising the following steps: S1, sequentially carrying out a primary doping process, a primary temperature testing process, a primary seeding process, a re-melting process, a supplementary doping process, a secondary temperature testing process, a secondary seeding process, a shouldering process and an equal-diameter process; s2, if NG appears in the guiding and releasing process or the equal-diameter process, re-melting the crystal bar and carrying out supplementary doping, and then sequentially carrying out a temperature testing process, a crystal guiding process, a shouldering process and an equal-diameter process; s3, when the sum of the first doping multiple and the supplementary doping multiple reaches the total doping multiple, supplementary doping is stopped. By controlling the doping interval time and the total doping multiple, the head resistivity can be reduced and controlled within the upper limit of the specification, and impurities can be doped more uniformly, so that the crystallization rate is increased, the drawing and discharging times are reduced, and the quality of the drawn monocrystalline silicon is ensured.

The invention relates to an M-type barium ferrite single crystal material and a preparation method and application thereof.The preparation method comprises the steps that metal source mixed powder and a fluxing agent are evenly mixed and subjected to primary sintering, and the metal source mixed powder comprises a barium source and an iron source; and carrying out secondary sintering on the obtained intermediate powder to obtain the M-type barium ferrite single crystal material. Wherein the secondary sintering comprises a heating stage, a heat preservation stage and a cooling stage, and the cooling stage comprises first-stage cooling, second-stage cooling and third-stage cooling which are sequentially carried out. According to the invention, the fluxing agent and the raw materials are added to form a eutectic system, melting can be realized at a temperature far lower than the melting point of the raw materials, and the cooling process is accurately controlled to slowly separate out the target M-type barium ferrite single crystal from the supersaturated molten liquid and reduce thermal stress and defects, so that the M-type barium ferrite single crystal material with high integrity and high purity is obtained. And moreover, the preparation method disclosed by the invention is simple, low in cost and easy for large-scale industrial production.

The invention discloses a method for low-temperature synthesis of an ultra-high nickel single crystal positive electrode material based on a molten salt fluxing agent method, which comprises the following steps: mixing an ultra-high nickel precursor with the nickel content of more than or equal to 90% with a lithium source according to a stoichiometric ratio, then adding a certain mass of sodium chloride (NaCl) as a fluxing agent medium, and fully grinding; the mixed material is subjected to temperature programming sintering in an oxygen-containing atmosphere, and the highest sintering temperature is controlled between 700 DEG C and 850 DEG C; and cooling, washing, drying and sieving the sintered product to finally obtain the small-size ultrahigh-nickel single-crystal positive electrode material with good dispersity. By introducing the low-melting-point molten salt fluxing agent, the growth temperature of the single crystal is remarkably reduced, lithium volatilization and abnormal growth and agglomeration of crystal grains are effectively inhibited, and the obtained single crystal particles are uniform in size (2 microns) and have a good layered structure and electrochemical performance. The method is simple in process, low in cost and suitable for large-scale production of the ultrahigh-nickel single-crystal positive electrode material for the high-performance lithium ion battery.

The invention provides a method for preparing a uranium dioxide single crystal by using a molten salt method and the obtained uranium dioxide single crystal, aiming at solving the problem that the growth of different crystal faces cannot be controlled when the uranium dioxide single crystal is prepared by using an existing fluxing agent method. The method comprises the following steps: in the presence of a reducing agent and a surface active substance, heating U3O8 powder in molten salt to a heat preservation temperature, preserving heat, and then cooling and growing to obtain the uranium dioxide single crystal, wherein the surface active substance is SiO2 (silicon dioxide), GeO2 (germanium dioxide), V2O5 (vanadium pentoxide) or Na2WO4 (titanium dioxide). According to the method, U3O8 is taken as a raw material, a molten salt fluxing agent is combined, the reducing agent is used for reducing U3O8 and growing the UO2 crystal, and the preferred crystal face of UO2 in the nucleation and growth processes is effectively controlled by selecting a proper surface active substance and changing the surface energy of UO2 in the nucleation and growth processes, so that the UO2 single crystal with the preferred crystal face and an ordered structure is obtained.

The invention discloses a method for growing a large-size CLBO crystal by using a new fluxing agent, and belongs to the field of nonlinear optical crystals. The adopted new fluxing agent is Cs2O-Li2O-B2O3-YF3, and the large-size CLBO crystal can be obtained through growth by a high-temperature solution top oriented seed crystal growth method. According to the novel fluxing agent, the solution viscosity can be effectively reduced, and crystal defects are reduced; and the grown large-size CLBO crystal has the advantages of high transmittance, strong deliquescence resistance and the like, and can be used as a frequency doubling device of an ultraviolet laser.

The invention relates to a novel second-order nonlinear optical crystal-potassium cadmium germanate (K4Cd3Ge4O13), and belongs to the field of optical crystal materials. The crystal is prepared by adopting a high-temperature solid-phase method and a high-temperature solution method, belongs to an orthorhombic crystal system and a C2 space group, is accurate in measurement of cell parameters, and shows excellent nonlinear optical characteristics and a wide light transmission range. The ultraviolet cut-off edge of the crystal is 261 nm, the infrared spectrum permeability is not obviously reduced in the range of 4000-714 cm <-1 >, the transmission range of the crystal can effectively cover a key atmosphere transmission window of 3-5 microns, and the crystal has powder frequency doubling response equivalent to that of a KDP crystal and can be applied to an all-solid-state laser as a mid-infrared nonlinear optical crystal.

Semiconductor substrate of a nitride of a group III element, comprising: a first surface; and a second surface where the distortion of a crystal plane of the first surface exhibits a multitude of extremes.

The application discloses a zinc oxide whisker heating furnace and a control method thereof, and belongs to the field of zinc oxide whisker production equipment. The zinc oxide whisker heating furnace comprises a furnace body, a whisker collecting groove and a lifting mechanism connected with a furnace cover. A zinc wire winding mechanism is rotatably connected to the furnace cover. The top end of a connecting rod of the whisker collecting groove is provided with a clamping groove, and the middle part is provided with an annular groove. A silicon carbide connecting rod is connected to the zinc wire winding mechanism, and the silicon carbide connecting rod is matched with the clamping groove. A rotating table is fixedly connected to a supporting frame. The rotating table is fixedly provided with a first electric telescopic mechanism extending towards the furnace body. The first electric telescopic mechanism is fixedly connected with a second electric telescopic mechanism. The second electric telescopic mechanism is connected with a clamping jaw matched with the annular groove. A controller is connected with the lifting mechanism, the rotating table, the first electric telescopic mechanism and the second electric telescopic mechanism. The scheme can realize automatic taking out and installation of the whisker collecting groove, and manual taking out with the aid of tools or waiting for the whisker collecting groove to cool down is not needed, so that the safety of zinc oxide whisker production is ensured.

The invention belongs to the technical field of nonlinear optical crystals, and particularly relates to a zeolite-like structure nitrogen oxide silicate nonlinear optical crystal and a preparation method and application thereof, the chemical general formula of the crystal is Ba3Si3N5OCl, the crystal belongs to a hexagonal system, the cell parameters of the crystal are as follows: a is 9.5147 (6), c is 5.5002 (4), V is 431.22 (6) 3, Z is 2, the space group is P-62c, and the crystal has a non-centrosymmetric structure. The Ba3Si3N5OCl crystal provided by the invention is used as a novel zeolite-like structure nitrogen oxide silicate, successfully integrates nonlinear optical activity and phase matching capability, can generate frequency doubling response which is about 0.2 times of KDP (potassium dihydrogen phosphate) under 1064 nm laser pumping, and can realize phase matching, so that the Ba3Si3N5OCl crystal becomes a nonlinear optical material with practical device application potential.

The invention relates to the technical field of heat-insulating and demagnetizing refrigeration, and discloses a heat-insulating and demagnetizing refrigeration material based on a Trellis crystal lattice and a preparation method and application of the heat-insulating and demagnetizing refrigeration material. The chemical formula of the heat insulation and demagnetization refrigeration material based on the Trellis crystal lattice is Gd2GeB2O8. A magnetic test result of the Gd2GeB2O8 crystal shows that the magnetic anisotropy of the crystal material is relatively weak and tends to magnetic isotropy, and a long-range magnetic orderliness phenomenon is not observed above 1.8 K. And when adiabatic demagnetization is carried out under initial conditions that T is equal to 3K and B is equal to 7T, the material can reach the maximum negative magnetic entropy difference of 51.68 J * kg <-1 > * K <-1 >, which shows that the Gd2GeB2O8 has a better application prospect in a 3-17K temperature zone and a sub-Kelvin temperature zone.

The present invention relates to a rubidium fluoro-scandium borate compound, a rubidium fluoro-scandium borate nonlinear optical crystal, and a preparation method and application thereof. The rubidium fluoro-scandium borate compound has a chemical formula Rb2ScB3O6F2, does not contain a symmetry center and has a molecular weight of 382.33 g / mol. The rubidium fluoro-scandium borate nonlinear optical crystal belongs to the monoclinic crystal system, and belongs to the non-centrosymmetric space group P21, and the unit cell parameters are: a=4.0372(10) Å, b=11.800(3) Å, c=8.823(2) Å, α=γ=90°, β=98.327(11)°, Z=2. The present invention adopts a high-temperature vacuum packaging method or a solid-state synthesis method to prepare rubidium fluoro-scandium borate compounds. The present invention adopts a fluxing agent method to prepare a rubidium fluoro-scandium borate nonlinear optical crystal, which have the advantages of short absorption cutoff edge, large nonlinear optical effect, good thermal stability, and stable physical and chemical properties. The rubidium fluoro-scandium borate nonlinear optical crystal of the present invention can be used to fabricate nonlinear optical devices, which have important applications in fields such as optics, military, laser lithography, and communication, etc.

Disclosed are a doped PbTiO3 perovskite single crystal seed and a method for preparing the same. The doped perovskite single crystal seed contains Pb, Bi, and Ti, and has a composition of (PbBix)TiO3, where 0.01≤x≤0.1.

The invention provides a layered Van der Waals material with full-compensation ferrimagnetism and a topological Hall effect as well as a preparation method and application of the layered Van der Waals material. The chemical formula of the material is MnxCrTe2, wherein 0 lt; and x is 1. The material provided by the invention has a wide compensation temperature range, a large magnetoresistance effect, anisotropy and a topological Hall effect, is a CrTe2 intercalation ferromagnetic material doped in different proportions, and can realize optimization and continuous adjustability of performances such as magnetism, Curie temperature and Hall parameters of the material through regulation and control of mechanisms such as the doping proportion, the temperature and the magnetic field; and a material basis is provided for researching the application of the Mn intercalation CrTe2 crystal material in the field of magnetic induced storage.

Provided is a group III element nitride substrate in which the occurrence of warpage is suppressed. A group III element nitride substrate according to an embodiment of the present invention is a group III element nitride substrate having a first main surface and a second main surface facing each other, wherein the variation range of Young's modulus in the thickness direction is 50% or less.

The invention belongs to the technical field of hexagonal boron nitride single crystal growth, and discloses a reusable crucible for growing a large-size hexagonal boron nitride single crystal, which comprises a crucible main body, a crucible upper half part and a crucible lower half part, and the crucible upper half part and the crucible lower half part are fixed by a connecting structure; the upper half part of the crucible is in a straight cylinder shape; the inner wall of the lower half part of the crucible is a combination of an inverted circular truncated cone-shaped inner wall and a straight cylinder-shaped inner wall; and the crucible cover is arranged on the surface of the upper half part of the crucible. According to the invention, the crucible is designed into a separated structure, and the upper half part of the crucible is detachable and can be repeatedly used; the inner wall of the bottom of the crucible at the lower half part is designed into an inverted circular truncated cone-shaped structure, so that the transverse corrosion of a fluxing agent to the inner wall of the crucible can be reduced, the metal cast ingot and the hexagonal boron nitride single crystal on the surface of the metal cast ingot can be taken out of the crucible more easily, and the crucible can be repeatedly used; meanwhile, the structure can reduce the flow velocity of the fluxing agent on the growth surface, weaken the vortex at the bottom of the fluxing agent in the growth process and improve the growth quality of the hexagonal boron nitride crystal.

This invention discloses a barium borate crystal, its preparation method, and its applications. The barium borate crystal has the chemical formula Ba₂BeB₂O₆, a non-centrosymmetric structure, belongs to the orthorhombic crystal system, has the space group Pca₂₁, and its cell parameters are α = 90°, β = 90°, and γ = 90°. This barium borate crystal exhibits extremely low birefringence from the ultraviolet to the infrared band, and its extremely low birefringence supports its application on zero-order glass slides.

Provided is a method of inspecting a Group-III element nitride substrate, the method including: preparing a Group-III element nitride substrate doped with an element except a Group-III element; irradiating the Group-III element nitride substrate with excitation energy; and measuring a half width of a band-edge emission peak of an emission spectrum obtained by the irradiation.

The invention relates to the technical field of beta-Ga2O3 crystal material growth, in particular to a fluxing agent of a beta-Ga2O3 crystal and a preparation method of a single crystal X-ray detector of the fluxing agent. A fluxing agent for growing the beta-Ga2O3 crystal comprises tellurium oxide and divalent alkaline earth metal carbonate. Uniformly mixing gallium oxide and a fluxing agent to obtain a mixed material; transferring the mixed material into a crystal growth furnace, and heating to melt the mixed material to obtain a melt; and cooling the melt to 0.5-3 DEG C above the saturation point temperature, putting a seed crystal into the melt, cooling to enable the crystal to grow, taking out the crystal after the growth is finished, and cooling to room temperature to obtain the beta-Ga2O3 crystal. The fluxing agent provided by the invention does not contain toxic components such as lead, fluorine and the like, the crystal growth temperature range of the fluxing agent is approximately 780-850 DEG C, the growth temperature of the crystal is effectively reduced, the volatilization of a melt at a high temperature is reduced, the deviation and viscosity of solution components are reduced, the corrosion to a platinum crucible is reduced, and the beta-Ga2O3 crystal with high quality and large size is easy to obtain.

A method for growing a periodically poled nonlinear crystal may comprise introducing a seed crystal into a melt to form a seed-melt mixture, wherein the seed crystal may comprise strontium tetraborate (SBO) and / or lithium triborate (LBO), and wherein the melt comprises a mixture of Sr, B, and O and / or a mixture of Li, B, and O. The method may further comprise heating the seed-melt mixture to a predetermined temperature until the periodically poled nonlinear crystal forms.

To provide a garnet-structured aluminate scintillating material doped with a transition metal element having an ionic radius and electronegativity similar to Al3+, and an outer electron configuration of [Ar]3dn4s1-2 (n≥5), as well as a preparation method and application thereof.SOLUTION: The chemical formula of the transition metal element doped garnet-structured aluminate scintillating material is RE3-x-aCexAaAl5-y-zDyMzO12, wherein x is 0<x≤0.15, y is 0≤y≤3, z is 0<z≤0.1, and a is 0≤a≤0.1; the rare earth element RE is at least one selected from Gd, Lu, Y, Sc, La, Nd, Eu, Tb, Dy, Ho, Er, Tm, and Yb, the A is at least one selected from Li, Mg, Ca, K, and Na, the D is at least one selected from Ga and In, and the M is a transition metal element, which is at least one selected from Cr, Mn, Fe, Co, and Ni.SELECTED DRAWING: Figure 1

The invention provides a lead titanium tellurate second-order nonlinear optical crystal and a preparation method and application thereof, and belongs to the technical field of optical crystal materials. The compound is prepared by a solid-phase synthesis method and a fluxing agent method, and the preparation method comprises the step of growing the titanium lead tellurate nonlinear optical crystal by adopting the fluxing agent method. The obtained product has the advantages of large frequency-doubled effect, large optical band gap, wide transmission range, stable physical and chemical properties and difficulty in deliquescence, and can be used for preparing near-intermediate infrared nonlinear optical frequency conversion devices.

The application provides a niobium phosphate nonlinear optical crystal and preparation and application thereof. 12 Nb3P7O 31 , belongs to an orthorhombic system, a space group is Pna21, is a non-central symmetric structure, cell parameters are: a=0.5 nm, b=1.0 nm, c=0.5 nm, and Z=4, has a large nonlinear optical effect (3xKDP), is phase-matched, a theoretical indirect band gap is 5.11 eV, has a large laser damage threshold, a wide transmission range, stable physical and chemical properties, good mechanical properties, is not easy to deliquesce, and is easy to preserve, and can be used as a ferroelectric crystal, a pyroelectric crystal or a laser substrate material, and is widely applied in preparation of middle infrared laser nonlinear optical composite functional devices, piezoelectric devices, laser frequency conversion devices and the like.

To provide a method for producing a Group III element nitride crystal by growing it on a plane on the -c-plane side as a crystal growth plane. The present invention is a method for producing a Group III element nitride crystal, including a vapor phase growth step of growing a Group III element nitride crystal 12 on a crystal growth plane of a Group III element nitride seed crystal 11 by vapor deposition. The vapor phase growth step is a step of causing a Group III metal, an oxidant, and a nitrogen-containing gas to react with one another to grow the Group III element nitride crystal 12 or includes: a reduced product gas generation step of causing a Group III element oxide and a reducing gas to react with each other to generate a gas of a reduced product of the Group III element oxide; and a crystal generation step of causing the gas of the reduced product and a nitrogen-containing gas to react with each other to generate the Group III element nitride crystal 12. The crystal growth plane is a plane on the -c-plane side. A crystal growth temperature is 1200°C or more. In the vapor phase growth step, the Group III element nitride crystal is grown in an approximately -c direction.

A single crystal diamond material comprising a single crystal diamond and an altered portion present on the outer periphery of the single crystal diamond, wherein the nitrogen atom content in the single crystal diamond is 1 ppm or more and 2000 ppm or less based on the atomic number, and the single crystal diamond material has a core electron excitation spectrum of the altered portion obtained by electron energy loss spectroscopy using a transmission electron microscope, in which an energy loss of π exists in a range of 285 eV±5 eV. * Maximum intensity of the peak Iπ * and the energy loss is in the range of 291±5 eV. * Maximum intensity of the peak Iσ * Ratio to Iπ * / Iσ * is 0.15 or more, and in the altered portion, the percentage {N1 / (N1+N2)}×100 of the number N1 of primary carbon atoms to the sum N1+N2 of the number N1 of primary carbon atoms constituting amorphous carbon and the number N2 of secondary carbon atoms constituting graphite is 90% or more.