55 results about "Phosphate crystals" patented technology

The invention provides a method for efficiently recovering low-concentration copper ions in wastewater based on phosphoric acid gradient regulation and seed crystal induction, which comprises the following steps: firstly, removing impurities such as Fe < 3 + >, Al < 3 + > and the like by using an acid-resistant flocculant under an acidic condition, and carrying out solid-liquid separation; adding nano hydroxyl copper phosphate seed crystals and a phosphoric acid solution into the supernate, inducing to generate high-purity copper phosphate crystals through stepped stirring under a neutral condition, and synchronously strengthening solid-liquid separation; the separated precipitate part is subjected to low-temperature calcination to be regenerated into active seed crystals for cyclic utilization, and the rest part is subjected to washing and vacuum drying to prepare a high-purity copper phosphate product. According to the method, gradient pH regulation and control, seed crystal induced crystallization and closed-loop regeneration technologies are innovatively combined, the copper ion recovery rate is larger than 95%, the product can be directly used for production of catalysts or battery materials, meanwhile, the agent consumption is reduced by 40% or above, the sludge amount is reduced by 50%, and high efficiency, economical efficiency and environmental protection value are achieved.

The invention discloses preparation and application of a nickel selenide / ferronickel phosphate crystal / amorphous heterogeneous catalyst, and relates to the technical field of electrochemistry. Selenizing the foamed nickel at low temperature in an inert atmosphere to generate a crystalline NiSex layer in situ; and by taking the obtained electrode as a working electrode, carrying out electrodeposition in a deposition solution containing nickel salt, ferric salt, hypophosphite and acetate by adopting a cyclic voltammetry method, so that amorphous NiFePOy is deposited on the surface of NiSex, and a NiSex / NiFePOy crystal / amorphous heterostructure nanosheet layer is constructed and is used for an alkaline medium urea oxidation reaction. The invention has the following beneficial effects: crystalline / amorphous interface coupling and a nanosheet self-supporting structure synergistically improve active sites and charge transfer capability, reduce energy consumption and improve current output; meanwhile, the electrode stability and durability are enhanced; the method has the advantages of low material cost, mild and simple process, suitableness for amplified preparation, and application potential of urea-assisted water electrolysis energy-saving hydrogen production.

The present invention discloses a method for preparing anhydrous iron phosphate from medium and low grade phosphate rock, which comprises the following steps: Step 1: Provide medium and low grade phosphate rock; Step 2: Mix the phosphate rock with hydrochloric acid in a decomposition tank and fully react to obtain a first slurry; Step 3: Place the first filtrate into a sedimentation tank; Step 4: Add mixed acid to calcium dihydrogen chloride phosphate crystals, carry out pulping and filtration to obtain a second filtrate and a filter cake; Step 5: Finally, filter to obtain a gypsum product and a third filtrate; Step 6: The third filtrate in Step 5 is purified with saturated ferrous sulfate. The fourth filtrate obtained through a microfilter is continuously added with a saturated ferrous sulfate solution, then continuously added with 5-25% hydrogen peroxide, reacted for 5-35 minutes, then added with sodium hydroxide solution to adjust the pH value to 1.9-2.1, and kept warm and continuously reacted for 3-6 hours, and the iron phosphate obtained by filtration; Step 7: Dry the iron phosphate obtained in Step 6 at 150-170 °C to obtain anhydrous iron phosphate.

The present invention provides a method for highly efficient recovery of low-concentration copper ions in wastewater based on phosphoric acid gradient regulation and seed induction. First, under acidic conditions, acid-resistant flocculants are used to remove impurities such as Fe<supgt;3+< / supgt> and Al<supgt;3+< / supgt>, followed by solid-liquid separation; subsequently, nano-hydroxy copper phosphate seeds and phosphoric acid solution are added to the supernatant, and high-purity copper phosphate crystals are induced to form through stepwise stirring under neutral conditions, while simultaneously strengthening solid-liquid separation; a part of the separated precipitate is regenerated into active seeds by low-temperature calcination for recycling, and the remaining part is washed and vacuum dried to obtain high-purity copper phosphate products. The present invention innovatively combines gradient pH regulation, seed-induced crystallization, and closed-loop regeneration technology, achieving a copper ion recovery rate > 95%. The product can be directly used in the production of catalysts or battery materials, while reducing the consumption of chemicals by more than 40% and reducing the sludge volume by 50%, combining high efficiency, economy, and environmental protection value.

According to the preparation method, iron ions and phosphate ions are in a high-temperature and high-pressure environment, seed crystal generation and growth are controlled by presetting a specific crystal form, a large number of microcrystals are prevented from being instantly formed, the crystal size is controllable, the crystallinity is high, the consistency is good, and the conversion rate and the crystallization quality of the anhydrous iron phosphate are improved. Anhydrous iron phosphate is directly synthesized, sintering, dehydration and crystallization are not needed, washing water is greatly reduced, energy consumption and waste discharge are reduced, the influence of sintering on product quality fluctuation and poor consistency is avoided, and the production cost is reduced; the crystallinity and the particle size of the final iron phosphate crystal are adjusted by regulating and controlling the seed crystal type, the particle size and the dosage of the seed crystal, the dropwise adding speed and the stirring rotating speed of the iron source and the phosphorus source and the temperature and pressure during reaction, and on the premise that the high crystallinity and the stable and high iron-phosphorus ratio are kept, the specific surface area is adjustable within the range of 5-15 m < 2 > / g, the D50 is adjustable within the range of 0.8-12 microns, and the tap density is adjustable within the range of 0.6-1.55 g / cm < 3 >. And different application requirements are met.

A whitlockite preparation method includes: determining a size of the whitlockite crystal to be prepared; determining a first amount of a first cation other than calcium ion on the basis of the determined size of the crystal, wherein when the determined size of the whitlockite crystal is a first size, the first amount is determined to be a first value, wherein when the determined size is a second size larger than the first size, the first amount is determined to be a second value; mixing calcium ion and phosphate ion in order to prepare a first phosphate crystal, wherein the determined first amount of the cation other than calcium ion is also mixed therewith; mixing a second amount of cation other than calcium ion with phosphate ion to prepare a second phosphate crystal; and aging a solution containing the first phosphate crystal and the second phosphate crystal.

The application discloses a potassium dihydrogen phosphate solution cooling crystallization device and a use method thereof, and belongs to the technical field of crystallization devices. The device comprises a cooling cavity, a cooling pipe arranged at the central bottom of the cooling cavity, two turning plates, a push rod, a power source and two connecting rods. The two turning plates are respectively arranged at the two sides of the cooling pipe and are hingedly connected with the inner bottom of the cooling cavity. The two sides of the two turning plates are sealingly matched with the inner side wall of the cooling cavity. The one end of the connecting rod is connected with the other end of the turning plate. The power source is fixedly connected with the outer wall of the cooling cavity and is drivingly connected with the other end of the push rod. The two connecting rods are symmetrically fixedly connected with the inner top of the cooling cavity. The triangular cooling cavity is hingedly connected with the free end of the connecting rod, so that the longest side of the triangular cooling cavity is adjacent to the turning plate. The feeding port is arranged in the central top region of the cooling cavity. The application has the beneficial effects of improving the cooling effect, shortening the cooling time and improving the quality of the generated potassium dihydrogen phosphate crystal.

The present invention relates to the application of a methylene diboric acid second-order nonlinear optical crystal material in the field of nonlinear optics. The chemical formula of the crystal material is CH6B2O4, the molecular weight is 103.68, it belongs to the tetragonal crystal system, its space group is I41md, the unit cell parameters are α=β=γ=90°, Z=4, and the unit cell volume is . The methylene diboric acid crystal material of the present invention has excellent optical properties. Under 1064nm laser irradiation, the powder frequency harmonic intensity is approximately 0.3 times that of potassium dihydrogen phosphate crystal, and phase matching can be achieved. In addition, the single crystal preparation method of the second-order nonlinear optical material is simple, and its ultraviolet absorption cutoff edge is less than 190nm. These advantages make it have important application potential in the fields of laser frequency conversion, optical information processing, holographic storage, and optical communication.

The present application relates to the technical field of crystal nondestructive testing, and particularly relates to a crystal defect nondestructive testing method and system based on pumped probe transient absorption spectrum, which comprises the following steps: detecting a target region of a crystal to be tested by using pump light and probe light; collecting a transient absorption image of the target region according to a preset time delay between the pump light and the probe light, and extracting a target risk region; focusing the pump light and the probe light, and performing point-by-point scanning on the target risk region by using the focused pump light and probe light; collecting three-dimensional transient absorption intensity distribution and defect dynamic evolution data of each scanning point in the target risk region under different time delays; performing correlation calibration based on the transient absorption image and the three-dimensional transient absorption intensity distribution to obtain defect parameters; and constructing a damage prediction model based on sample damage threshold data, and outputting damage threshold prediction results according to the defect parameters. The purpose is to realize nondestructive and rapid detection of internal defects of deuterated potassium dihydrogen phosphate crystals.

The application belongs to the technical field of inorganic functional crystals, and particularly relates to a praseodymium ion doped phosphate crystal material and a preparation method and application thereof. The application provides a praseodymium ion doped phosphate crystal material, a chemical formula of the praseodymium ion doped phosphate crystal material is shown as formula 1: Ba3Y 1‑x (PO4)3:xPr formula 1; in formula 1, 0

The invention provides a positive electrode material, a positive plate, a battery and electric equipment, and relates to the technical field of batteries, the structure of the positive electrode material is a core-shell structure, a layered oxide is used as a core, and a polyanion material is used as a shell layer; the layered oxide is polycrystalline particles; the size of the ferric sodium pyrophosphate crystal in at least one dimension is 2-20 nm; and the size of the ferric sodium pyrophosphate crystal in at least one dimension is 500 nm to 1 [mu] m. According to the positive electrode material provided by the invention, the surface of the layered oxide particles is coated with the polyanion material which can be intercalated into the crystal gaps of the polycrystalline particles, so that lattice distortion of the O3-phase layered oxide is inhibited, and meanwhile, the charge-discharge capacity and the rate capability of the positive electrode material are optimized.

The invention provides a method for co-producing lithium hydroxide and lithium dihydrogen phosphate from crude lithium carbonate, which comprises the following steps: S1, pulping the crude lithium carbonate, mixing with a calcium-containing reagent, carrying out causticization reaction, and carrying out solid-liquid separation to obtain causticized liquid and causticized slag; s2, mixing a part of the causticized liquid with a first impurity removal agent and a second impurity removal agent for impurity removal, and after solid-liquid separation, taking a liquid phase to obtain a first impurity-removed liquid; and S3, mixing the first impurity-removed liquid with the remaining causticized liquid, performing resin impurity removal to obtain a second impurity-removed liquid, and performing evaporation concentration and solid-liquid separation on part of the second impurity-removed liquid in sequence to obtain lithium hydroxide crystals and lithium hydroxide mother liquor. And taking the residual second impurity-removed liquid in the step S3, and carrying out lithium precipitation and acidification to prepare lithium dihydrogen phosphate crystals. The problem of product singleness of lithium enterprises is solved.

The application provides a positive electrode material, a positive electrode sheet, a battery and an electric device, and relates to the technical field of batteries.The structure of the positive electrode material is a core-shell structure, the inner core of which is a layered oxide and the outer shell layer of which is a polyanion material.The layered oxide is a polycrystalline particle.The size of the sodium iron pyrophosphate phosphate crystal in at least one dimension is 2-20 nm, and the size of the sodium iron pyrophosphate phosphate crystal in at least one dimension is 500 nm-1 mu m.The positive electrode material provided by the application is coated on the surface of the layered oxide particle by using a polyanion material which can intercalate into the crystal gap of the polycrystalline particle, so as to inhibit the lattice distortion of the O3 phase layered oxide, and meanwhile, the charge and discharge capacity and the rate performance of the layered oxide are optimized.

A whitlockite preparation method includes: determining a size of the whitlockite crystal to be prepared; determining a first amount of a first cation other than calcium ion on the basis of the determined size of the crystal, wherein when the determined size of the whitlockite crystal is a first size, the first amount is determined to be a first value, wherein when the determined size is a second size larger than the first size, the first amount is determined to be a second value; mixing calcium ion and phosphate ion in order to prepare a first phosphate crystal, wherein the determined first amount of the cation other than calcium ion is also mixed therewith; mixing a second amount of cation other than calcium ion with phosphate ion to prepare a second phosphate crystal; and aging a solution containing the first phosphate crystal and the second phosphate crystal.

The present invention relates to a molybdenum strontium peroxide second-order nonlinear optical crystal and its preparation and application. The chemical formula of the crystal material is SrMo2O3(O2)4(H2O)2·3H2O, the molecular weight is 545.58, it belongs to the tetragonal crystal system, its space group is , the unit cell parameters are α=β=γ=90°, Z=8, and the unit cell volume is . The molybdenum strontium peroxide crystal material of the present invention has excellent optical properties. Under 1064nm laser irradiation, the powder frequency harmonic intensity is about 3 times that of potassium dihydrogen phosphate crystal, and phase matching can be achieved. The crystal material is not only easy to grow, but also can effectively expand the wavelength range of coherent light sources through optical frequency conversion technologies such as second harmonic generation and optical parametric amplification. In the fields of laser lithography, laser processing, medical diagnosis and treatment, this crystal material shows important application prospects.

The present invention relates to a trimethylammonium methanesulfonate second-order nonlinear optical crystal material and its preparation and application. The chemical formula of the crystal material is [(CH3)3NH] + [SO3CH3] ‑ , molecular weight is 154.21, belongs to the orthorhombic system, space group is Pca21 (No.29). The unit cell parameters are α=γ=β=90°, Z=4, and the unit cell volume is the nonlinear optical crystal [(CH3)3NH] + [SO3CH3] ‑ Under 1064nm laser irradiation, the powder's frequency-doubled effect is approximately 0.5 times that of potassium dihydrogen phosphate crystals, and phase matching is achieved, with a UV absorption cutoff edge less than 200nm. This crystal material is easy to grow and exhibits significant application value in electro-optical modulation, holographic storage elements, and frequency-doubled devices.

A sintered membrane is a ceramic article having a primary crystal phase including lithium-aluminum-titanium-phosphate crystals and a secondary crystal phase including anatase or lithium-titanium-oxyphosphate crystals. In aspects, the sintered membrane can have a closed porosity of less than or equal to 5%. In aspects, the primary crystal phase can be from 95% to 100% of a volume of the ceramic article, and the secondary crystal phase can be from greater than 0% to 5% of the volume of the ceramic article. In aspects, the sintered membrane can exhibit a total leaching of less than or equal to 5 parts-per-million in a Leaching Test. Methods of making a sintered membrane includes forming a green tape having lithium-aluminum-titanium-phosphate crystals and an additive including a titanium-containing powder or an aluminum-containing powder, where the green tape is heated to a first temperature from 600°C to 1200°C to form the sintered membrane.

The invention discloses a Fe (II)-based fluorine-containing phosphate crystal as well as a preparation method and application thereof. A fluorine-rich hydrothermal method based on an oxidation-reduction reaction is an effective path for preparing Fe (II)-based fluorophosphate. The structural formula of the Fe (II) group-containing fluorine-containing phosphate crystal is BaFePO4F, the Fe (II) group-containing fluorine-containing phosphate crystal is crystallized in an orthorhombic crystal system, and the space group is P212121. According to the invention, the Mssbauer spectrum of the BaFePO4F is analyzed, Fe is proved to be II valence, the analysis of the magnetic susceptibility and specific heat of the BaFePO4F also finds that the BaFePO4F has antiferromagnetic interaction, and the antiferromagnetic ordered temperature of the BaFePO4F is 13.5 K. The invention also discloses a preparation method of the BaFePO4F. The Fe (II)-based fluorine-containing phosphate is stable in physical and chemical properties and easy to process and preserve; reagents and raw materials adopted by the method have low toxicity to human bodies, the production period is short, and the cost is low.

The invention discloses a cylindrical light-transmitting frequency doubling device for generating tunable yellow light and a laser device, and belongs to the nonlinear optical technology, the cylindrical light-transmitting frequency doubling device comprises a rubidium titanyl phosphate crystal, the rubidium titanyl phosphate crystal is processed into a cylinder along the Y-axis direction, and the cylindrical surface of the cylinder is plated with a dual-waveband antireflection film of 1140-1180 nm and a dual-waveband antireflection film of 570-590 nm. By means of the cylindrical surface light-passing frequency doubling device, the comprehensive performance of the yellow light frequency doubling device can be improved.

The invention provides a positive electrode material with a core-shell structure, a positive electrode, a battery and electric equipment, and relates to the technical field of batteries, the positive electrode material with the core-shell structure takes O3-phase layered oxide polycrystalline particles as a core, and takes whisker-shaped ferric sodium pyrophosphate phosphate crystals as a shell; and whisker-shaped ferric sodium pyrophosphate crystals partially positioned on the interface of the inner core and the shell are obliquely embedded into the inner core. The shell material part of the positive electrode material of the core-shell structure provided by the invention is obliquely inserted into the inner core to form an oblique pinning structure, so that the interface bonding strength of the shell and the inner core can be improved, and the expansion inhibition effect of the shell on the inner core is improved.

The invention discloses a multilayer crystal coated controlled-release nitrogen fertilizer based on root system organic acid triggering and a preparation method thereof, and belongs to the technical field of controlled-release fertilizers. The fertilizer is a multi-layer controlled-release nitrogen fertilizer formed by sequentially coating a Zn-Mg phosphate crystal layer, a PLGA temperature-sensitive layer and a Ca / Fe cross-linked chitosan-succinic acid trigger layer with urea or urea formaldehyde particles as a core. The crystal layer in the fertilizer provides 90-120 d baseline slow release, the temperature-sensitive layer is subjected to peak clipping, the outermost layer disintegrates under the action of rhizosphere organic acid, micropores are exposed, and on-demand nitrogen supply is achieved. Field tests show that compared with common urea, the nitrogen utilization rate of the fertilizer is increased by about 50%, nitrogen leaching loss and ammonia volatilization are reduced by about 60%, the yield is remarkably increased, and the technical effect is remarkable.

The application relates to a kind of ferric phosphate and its preparation method and application, the preparation method comprises the following steps: (1) after nanocellulose is treated by corona discharge, mixed with water and organic acid, esterified nanocellulose dispersion is obtained;(2) the esterified nanocellulose dispersion is mixed with oily solvent, and emulsion is obtained by emulsification treatment;(3) iron salt solution is mixed with the emulsion, one-step stirring is carried out, phosphate solution is added, the pH of mixed solution is adjusted, two-step stirring is carried out, and the ferric phosphate is obtained by sintering.The charged nanocellulose is formed into emulsion ball, and metal cation is directionally adsorbed on the surface of nanocellulose, finally reacts with phosphate ion to obtain ferric phosphate crystal with good dispersity, and the breaking difficulty of agglomerated ferric phosphate is reduced.

The application provides a method for separating potassium and sodium in a phosphate mother liquor, comprising the following steps: firstly, potassium in the phosphate mother liquor containing potassium and sodium is precipitated from the phosphate mother liquor in the form of potassium dihydrogen phosphate to obtain a potassium-removed mother liquor; and then, sodium in the potassium-removed mother liquor is crystallized and separated to realize the separation of potassium and sodium; specifically, the method comprises the following steps: S1. potassium removal: adjusting the pH value of the phosphate mother liquor to 4.0-5.0, then cooling and crystallizing, and centrifugally separating to precipitate potassium dihydrogen phosphate crystals, and obtaining the potassium-removed mother liquor; S2. sodium removal: adjusting the pH value of the potassium-removed mother liquor to 7.5-8.5, then cooling and crystallizing, and centrifugally separating to precipitate ammonium sodium phosphate crystals, and obtaining the sodium-removed mother liquor; the separation method separates potassium and sodium in the mother liquor, removes sodium impurities in the system, purifies the mother liquor, improves the quality of the circulating mother liquor, ensures the normal operation of the production system, and achieves the purposes of improving the product quality and improving the production capacity.

The utility model discloses an energy-saving ball mill which comprises a machine shell, a feeding mechanism is arranged on one side of the machine shell, a discharging port is fixedly connected to the lower end of the machine shell, a roller is arranged in the machine shell, steel balls are arranged in the roller, a plurality of sieve holes are formed in the outer surface of the roller at equal intervals, and the sieve holes are communicated with the feeding mechanism. One end of the roller is fixedly connected with an annular gear, a frame-shaped support is arranged at the lower end of the side, close to the annular gear, of the machine shell, a motor is fixedly installed on one side of the frame-shaped support, the output end of the motor penetrates through the frame-shaped support and is fixedly connected with a circular gear, and the circular gear is meshed with the annular gear. According to the utility model, the screening holes are formed in the roller, so that the situation that the expected granularity cannot be achieved by grinding monoammonium phosphate crystal materials is prevented.

The application provides a polishing method for large-diameter potassium dihydrogen phosphate crystal elements, which can realize fast convergence of crystal surface shape precision, and comprises the following steps: 1) configuring an oil-based polishing liquid; 2) pasting a vacuum adsorption pad on the surface of a substrate with the same size as the crystal element; 3) pasting a light-induced debonding protective tape on the back surface of the crystal element, adsorbing the crystal element on the vacuum adsorption pad, and mounting the crystal element on a tool of a machine tool; 4) performing fast polishing on the processed surface of the crystal element; 5) after the fast polishing is completed, lifting a workpiece disc, and taking the crystal element and the substrate off the polishing disc; and 6) performing fast polishing on the crystal element after turning over. The crystal element is processed by using the method of full-diameter polishing of a hard polishing disc, the full surface of the crystal element is in contact with the polishing tool at the same time in the polishing process, fast processing based on the rigid pair of research is realized, the crystal surface shape precision is fast converged, and the method can be widely applied to the processing of various specifications of optical elements.

The application provides a core-shell structure positive electrode material, a positive electrode, a battery and an electric device, and relates to the technical field of batteries.The core-shell structure positive electrode material has a layered oxide polycrystal particle in O3 phase as an inner core and a whisker-shaped sodium iron pyrophosphate phosphate crystal as an outer shell; and the whisker-shaped sodium iron pyrophosphate phosphate crystals located on the interface between the inner core and the outer shell are inclinedly embedded in the inner core.The outer shell material of the core-shell structure positive electrode material provided by the application is partially inclinedly inserted into the inner core to form an inclined pinning structure, which can improve the interface bonding strength of the outer shell and the inner core and improve the expansion inhibition effect of the outer shell on the inner core.

The present application relates to chemical technology field, and discloses a kind of two end tapering instant potassium dihydrogen phosphate crystal and preparation method thereof;The crystal X-ray powder diffraction diagram has 17 characteristic peaks at 2θ=16.8±0.2°, 23.1±0.2° and the like, and is formed by microcrystalline directional assembly;Preparation method is as follows: potassium dihydrogen phosphate is dissolved in water to form saturated solution at 50-80 ℃, one or more of iron chloride hexahydrate, iron sulfate, iron phosphate is added as inorganic salt ion additive, after filtering to remove insoluble matter, it is cooled to 0-30 ℃ crystallization under stirring, after filtration, it is washed with anhydrous ethanol, acetone or saturated potassium dihydrogen phosphate solution, and vacuum drying at 30-65 ℃ is obtained.The process is simple, energy consumption is low, and reproducibility is high, product purity is more than 99%, and the yield is more than 60%, and the mother liquor can be recycled.The solubility and dissolution rate of the obtained crystal are better than those of commercial products, and it is suitable for instant water-soluble fertilizer.

The invention relates to the technical field of crystal nondestructive testing, in particular to a crystal defect nondestructive testing method and system based on a pumping detection transient absorption spectrum, and the method comprises the following steps: detecting a target area of a crystal to be detected by utilizing pumping light and detection light; according to a preset time delay between the pump light and the probe light, collecting a transient absorption image of the target area, and extracting a target risk area; focusing the pump light and the probe light, and performing point-by-point scanning on the target risk area by using the focused pump light and probe light; acquiring three-dimensional transient absorption intensity distribution and defect dynamic evolution data of each scanning point in the target risk area under different time delays; performing correlation calibration based on the transient absorption image and the three-dimensional transient absorption intensity distribution to obtain defect parameters; and constructing a damage prediction model based on the sample damage threshold data, and outputting a damage threshold prediction result according to the defect parameters. The objective of the invention is to realize nondestructive and rapid detection of internal defects of the deuterated potassium dihydrogen phosphate crystal.

The present invention relates to a second-order nonlinear optical crystal of formamidine thiosulfate, and its preparation and application. The crystal material has a chemical formula of [CH(NH2)2]2SO3S, a molecular weight of 203.27, belongs to the orthorhombic crystal system, has a space group of P212121, unit cell parameters of α=β=γ=90°, Z=4, and a unit cell volume of . The formamidine thiosulfate crystal material of the present invention has excellent optical properties. Under 1064nm laser irradiation, the powder frequency harmonic intensity is approximately twice that of potassium dihydrogen phosphate crystal, and phase matching can be achieved. In addition, the crystal material has a wide light transmission band, an ultraviolet absorption cutoff edge of 253nm, an optical band gap of 4.90eV, and is easy to grow. Optical frequency conversion technologies such as second harmonic generation and optical parametric amplification can be used to expand the wavelength range of coherent light sources. Therefore, the crystal material has important application value in fields such as laser frequency conversion and optoelectronic information storage.

The invention relates to a vanadium iodate second-order nonlinear optical crystal material and preparation and application thereof, the chemical formula of the vanadium iodate second-order nonlinear optical crystal material is VO2 (H2O) (IO3), the molecular weight is 275.86, the vanadium iodate second-order nonlinear optical crystal material belongs to an orthorhombic system, the space group of the vanadium iodate second-order nonlinear optical crystal material is Pca21, the cell parameter is # imgabs 0 # alpha = beta = gamma = 90 degrees, Z = 4, and the cell volume is # imgabs 1 #. The frequency doubling intensity of the powder under the irradiation of laser of 1200 nm is about 18.0 times of that of monopotassium phosphate crystal (KDP), the frequency doubling intensity of the powder under the irradiation of laser of 2100 nm is about 1.5 times of that of potassium titanyl phosphate (KTP), and phase matching can be achieved. In addition, the vanadium iodate crystal material also has large birefringence, and the birefringence reaches 0.184 at 546 nm. The research result shows that the crystal has wide application prospects in the fields of laser frequency conversion, photoelectric modulation, laser signal holographic storage and the like.