120 results about "Niobium pentoxide" patented technology

The invention relates to a method for preparing a pyrochlore oxyfluoride solid electrolyte by a one-step solid phase method, which comprises the following steps: uniformly mixing lithium carbonate (Li2CO3), lanthanum oxide (La2O3), niobium pentoxide (Nb2O5) and lithium fluoride (LiF), and carrying out high-temperature one-time sintering under protective gas to synthesize a Li2-xLa (1 + x) / 3Nb2O6F (LLNOF solid electrolyte material. The synthesis route is optimized, a single fluorine source is used, and the types of raw materials are reduced; according to the method, secondary sintering is not needed, the pure-phase electrolyte powder can be obtained by adopting one-step sintering synthesis, the steps are simple, the efficiency is high, the cost is reduced, and the resource consumption is reduced. According to the obtained LLNOF electrolyte material powder, the synthesis temperature ranges from 900 DEG C to 1100 DEG C, heating to 1100 DEG C or above is not needed, the requirement for heating equipment is low, large-scale mass production can be conducted, the sample yield is large, and energy consumption is low. Required synthesis equipment is simple and easy to obtain, and the ionic conductivity is good. The lithium ion conductor with high conductivity and stability in air is synthesized through a one-step method.

The present disclosure relates to embodiments of a method for manufacturing a ceramic material comprising the steps of (a) homogenizing aluminum oxide, niobium pentoxide and solvent; (b) ultrasonicating the blend obtained in step (a); (c) adding an aliquot of the prepared suspension to the empty cavity of a mold, particularly between the polymeric mold and the metal mold; (d) immersing the mold into a coolant liquid-containing bath for sufficient time to ensure that all parts are completely frozen; (e) removing the ceramic body from the mold; (f) removing the solidified phase by means of sublimation hence obtaining a green tube; and (g) sintering the green tube, so as to obtain a solid structure. The present disclosure further relates to embodiments of a ceramic material and its use to manufacture a microfiltration membrane and / or a membrane support for fluid separation.

The invention relates to the technical field of piezoelectric light-transmitting functional ceramics, and discloses a high-light-transmitting ceramic material and a preparation method thereof.The preparation method comprises the following preparation steps that sodium carbonate, potassium carbonate, niobium pentoxide, antimony trioxide, samarium oxide and zirconium dioxide powder raw materials are taken, and after primary ball milling and drying are conducted on the powder raw materials, mixed powder is obtained; carrying out pre-sintering and secondary ball milling on the mixed powder, carrying out compression molding to form a tablet, and sintering and polishing the tablet to obtain a ceramic matrix; and spraying the composite slurry to the surface of a ceramic matrix, carrying out heat treatment, and cooling to room temperature to obtain the high-transmittance ceramic material. The antimony trioxide, the samarium oxide and the zirconium dioxide are co-doped, an antimony-samarium-zirconium liquid phase is generated in the ceramic material, pores of the ceramic material are filled and eliminated, and the prepared ceramic material has excellent optical transmittance, piezoelectric property and mechanical strength.

The invention relates to the technical field of secondary batteries, provides a secondary battery and a preparation method thereof, an energy storage system and electric equipment, and at least facilitates the improvement of the use stability of the secondary battery. The method comprises the following steps: preparing a diaphragm: preparing a substrate layer which is made of polyimide and niobium pentoxide and has a fiber network structure; a self-repairing layer is prepared, the self-repairing layer is located on the surface of one side of the substrate layer, the material of the self-repairing layer comprises polyurethane containing dynamic disulfide bonds, and the surface, away from the substrate layer, of the self-repairing layer is grafted with-SO3Li groups; a positive plate and a negative plate are provided, the positive plate, the diaphragm and the negative plate are subjected to winding treatment or lamination treatment and then put into the shell, the self-repairing layer faces the negative plate, the substrate layer faces the positive plate, and electrolyte is injected into the shell to obtain the secondary battery.

The invention belongs to the technical field of metal preparation, and particularly relates to a Fe-Al-Nb alloy and a preparation method thereof. Comprising the following steps: mixing ferric oxide, niobium pentoxide powder and a metal diluent, performing ball milling, and pressing into a green body; and the blank is put into a reaction kettle, then an ignition agent is added, protective gas is inflated, a self-propagating reaction is conducted at the temperature of 260-300 DEG C, and the Fe-Al-Nb alloy is obtained. The Fe-Al-Nb alloy is prepared through the self-propagating reaction, the reaction temperature is reduced, the thermal stress during forming is improved, the temperature of the self-propagating reaction is only 260-300 DEG C, meanwhile, the self-propagating reaction mode is adopted, the alloy is rapidly cooled after reacting, the fine grain strengthening effect is promoted to be more obvious, a microstructure of a Fe3Al matrix phase and a C14 Laves reinforced phase is formed, and the Fe-Al-Nb alloy is obtained. And the distribution of a reinforced phase is more uniform, and the wear resistance of the material is improved.

The invention relates to a preparation method of a niobium pentoxide loaded molybdenum disulfide catalyst and application of the niobium pentoxide loaded molybdenum disulfide catalyst in lignin conversion. The preparation method comprises the following steps: dissolving ammonium molybdate heptahydrate and thiourea in distilled water, adding Nb2O5, and adjusting the pH value of the mixture to 0.8-1.1 by using hydrochloric acid; transferring the solution into a stainless steel autoclave for hydrothermal reaction; centrifugally separating to obtain a black precipitate, washing with water and absolute ethyl alcohol, and drying in vacuum overnight; and placing the obtained substance in a high-temperature and high-pressure reaction kettle, screwing the reaction kettle to seal the reaction kettle, discharging gas after introducing H2, discharging air in the device, pressurizing to 3-5 MPa, and reacting to obtain the catalyst Nb2O5-MoS2. The catalyst shows excellent activity of aromatic phenol and ether compound hydrodeoxygenation for aromatic hydrocarbon preparation. The invention provides the catalyst which is low in cost, simple and convenient to prepare and excellent in performance, after ten cycle experiments, the activity of the catalyst is still stable, and the indexes of the conversion rate and the yield are reduced by less than 5%.

The invention relates to a multi-element synergistic doped ATO target material and a preparation method thereof. Comprising the following steps: 1) uniformly mixing water and a powder dispersant, then adding an oxide 1 (at least one of tantalum pentoxide, niobium pentoxide, vanadium pentoxide, gallium oxide and tungsten trioxide), an oxide 2 (at least one of zinc oxide, copper oxide, cobalt oxide, manganese oxide and cerium oxide) and ATO raw material powder, and mixing and homogenizing to prepare slurry; 2) grinding the slurry and adding a powder forming adhesive; 3) carrying out spray drying granulation on the ground slurry; according to the preparation method, the ATO target material with high compactness (relative density gt, 98.5%) and low resistance (resistivity lt, 5 * 10 <-3 > omega.cm) is prepared through multi-element synergistic doping of the oxide, and the problem that compactness and conductivity of the ATO target material are difficult to consider at the same time in the prior art is solved.

The invention relates to the technical field of electrode materials, in particular to a compaction-resistant ultrahigh-nickel high-entropy positive electrode material as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out a co-precipitation reaction on a mixed salt solution and a mixed nano metal oxide sol under an alkaline condition to obtain a precursor; and mixing the precursor, a high-hardness nano metal oxide and a lithium source, and sintering to obtain the compaction-resistant ultrahigh-nickel high-entropy positive electrode material, the mixed salt solution comprises Ni < 2 + >, Co < 2 + > and Mn < 2 + >; the nano metal oxide in the mixed nano metal oxide sol comprises at least three of nano aluminum oxide, nano zirconium oxide, nano titanium dioxide and nano magnesium oxide; the high-hardness nano metal oxide comprises one or more of nano zirconium oxide, nano titanium dioxide, nano tungsten trioxide and nano niobium pentoxide. The compaction-resistant ultrahigh-nickel high-entropy positive electrode material prepared by the preparation method provided by the invention is uniform in granularity and high in compression resistance.

The invention discloses a current collector active material and a preparation method and application thereof, and relates to the technical field of electrochemical energy storage. Comprising the following steps: dissolving acid, a niobium precursor and aniline in water to form a solution A; dissolving ammonium persulfate in water to form a solution B, adding the solution B into the solution A, uniformly mixing, standing for reaction, carrying out suction filtration and drying to obtain niobium-doped polyaniline carbon nanotubes, and carrying out heat treatment on the niobium-doped polyaniline carbon nanotubes in a protective atmosphere to obtain amorphous carbon nanotubes embedded with niobium pentoxide nanoparticles. The method can be used for preparing a negative-electrode-free sodium metal battery current collector and a negative-electrode-free sodium metal battery. According to the method, hectogram or even kilogram-level superfine amorphous carbon nanotubes embedded with niobium pentoxide nanoparticles can be prepared in a single batch in a macroscopic manner, and Nb2O5 nanoparticles anchored in the carbon tubes are subjected to reversible intercalation pseudocapacitance reaction, so that the sodium ion migration rate is remarkably increased, sodium ions are preferentially adsorbed, the nucleation overpotential is greatly reduced, and the performance of the carbon nanotubes is improved. And the assembled negative-electrode-free sodium metal total battery shows an extremely high capacity retention ratio.

The invention discloses a method for preparing 6N and above high-purity Nb2O5 by using a niobium oxalate precursor, belongs to the technical field of niobium pentoxide preparation, and solves the problems of low purity and high impurity content of Nb2O5 prepared by the existing method. The method comprises the following steps: mixing niobium oxalate with high-purity water to obtain a mixed solution; performing cold crystallization purification; separating niobium oxalate crystals from the mother liquor, washing and drying; the method comprises the following steps: putting niobium oxalate crystals into a crucible, putting the crucible into a vacuum reaction distillation furnace, sealing a system, vacuumizing to below 1Pa, carrying out inert gas replacement, and then carrying out stage heating and heat preservation; cooling to 800-900 DEG C, introducing high-purity oxygen into the system, and carrying out oxidation stabilization treatment at a constant temperature; after treatment, continuously cooling to 200 DEG C or below, and then naturally cooling to room temperature to obtain a high-purity Nb2O5 product. The Nb2O5 product prepared by the method disclosed by the invention is high in purity and low in impurity content.

The invention discloses a preparation method of high-purity Nb2O5, belongs to the field of preparation of Nb2O5, and solves the problem of low purity of Nb2O5 prepared by the existing method. The preparation method comprises the steps that a metal niobium ingot with the purity larger than or equal to 99.999% is adopted, and vacuum drying is conducted after surface peeling, dilute nitric acid ultrasonic cleaning and high-purity water flushing are conducted; the pretreated niobium ingot is subjected to a hydrogenation reaction in a pure hydrogen atmosphere, niobium hydride is generated and then crushed, and niobium hydride powder is obtained; carrying out dehydrogenation treatment on the niobium hydride powder under a high vacuum condition; dissolving the metal niobium powder with electronic-grade hydrofluoric acid, and filtering to obtain fluorine niobic acid filtrate; performing multi-stage counter-current extraction and reverse extraction on the fluobiobic acid filtrate by adopting an extracting agent to obtain fluobiobic acid reverse extraction liquid; introducing high-purity ammonia gas into the fluobiobic acid strip liquor, and precipitating to generate niobium hydroxide; ageing, filtering and washing with high-purity water for multiple times to obtain a niobium hydroxide filter cake; and calcining the niobium hydroxide filter cake in a high-purity oxygen atmosphere in stages to obtain niobium pentoxide. The niobium pentoxide prepared by the method disclosed by the invention is high in purity.

The invention provides a preparation method of ultra-pure niobium pentoxide, which is stable in process and high in efficiency, and aims to reduce the silicon content to be less than 3ppm and obtain ultra-pure niobium pentoxide through the synergistic effect of directional dissolution silicon removal and precision filtration and washing impurity removal.

This invention discloses a method for preparing interface-reinforced niobium pentoxide / porous graphene and its energy storage application. The method involves adding porous graphene oxide during the solvothermal synthesis of a niobium pentoxide precursor to obtain a composite precursor of niobium pentoxide and porous graphene oxide. This precursor is then annealed under a protective atmosphere to obtain the interface-reinforced niobium pentoxide / porous graphene composite material. The composite material obtained by this invention exhibits excellent performance as an electrochemical energy storage material. Furthermore, the preparation method of this invention is simple to operate, requires no complex equipment, and is easily controlled, making it suitable for mass production.

The invention discloses a fast-response thermistor material suitable for an intelligent space expansion structure and a preparation method thereof. The method comprises the following steps: by taking yttrium oxide, tetraterbium heptaoxide, niobium pentoxide and praseodymium oxide as raw materials, mixing, grinding, calcining, regrinding, performing cold isostatic pressing, sintering at a high temperature and the like, thereby obtaining the fast-response thermistor material suitable for the intelligent space expansion structure. The niobate thermistor material is obtained. The thermistor has the advantages of being high in high-temperature stability, high in linearity, low in heat conductivity and the like, and the prepared niobate ceramic wafer-shaped high-density ceramic material is good in density, has the excellent negative temperature coefficient characteristic, and is fast in response and high in reliability; the temperature sensing material is suitable for high-precision and stable temperature monitoring in the work of an intelligent space expansion structure.

The application discloses a manganese-based composite monatomic catalyst and a method for propane low-temperature oxidation to prepare acetone, the manganese-based composite catalyst is characterized by taking manganese as an active component, at least one of iron, cobalt, copper and nickel as a first assistant, at least one of carbon and nitrogen as a second assistant, and at least one of aluminum oxide, cerium oxide, zinc oxide, zirconium oxide and niobium pentoxide as a carrier. The manganese-based composite monatomic catalyst is used in propane oxidation reaction with oxygen as an oxidant, and does not need to be matched with strong acid solvents, carbon monoxide and other harmful substances during use, is green and environment-friendly, can realize high-efficiency catalytic reaction under low-temperature conditions, and can obtain acetone with high selectivity, and the acetone yield can reach 45-55mmolg 催化剂 ‑1 h ‑1 The content of acetone in the liquid product can reach 65% at most, and the catalyst has excellent stability and can be stably recycled for 5 times without obvious deactivation.

The invention belongs to the technical field of lithium ion battery materials and electrochemistry, and discloses high-entropy doped niobium pentoxide nanoparticles as well as a preparation method and application thereof. The chemical formula of the nano-particles is Nb < 1-x > FeaCoeNiiCrjAlkO2, x = a + e + i + j + k, and x is larger than or equal to 0.04 and smaller than or equal to 0.06, 0 lt; a < lt >; 1, 0lt; lt, lt; 1, 0lt; ilt; 1, 0lt; jlt; 1, 0lt; klt; 1; the material has an orthorhombic system and a space group P2 / m, doped metal occupies Nb sites in an atomic-scale dispersion manner, and a unit cell parameter c axis is expanded to 0.41 nm; and the size of the nano particles is 50 to 200 nm. According to the preparation method, a hydrothermal method is combined with high-temperature sintering, niobium pentachloride is used as a niobium source, specific metal salt is used as a doping source, terephthalic acid is used as a ligand, and the material is prepared through the steps of solution preparation, hydrothermal reaction, drying and sintering. The nano-particles are high in electron conductivity and fast in lithium ion diffusion, the capacity reaches 156 mAh. G <-1 > under the rate of 100 C, the capacity retention rate is 88% or above after 1000 times of circulation under the rate of 10 C, and the nano-particles can be used as an excellent lithium ion battery negative electrode material and are suitable for the field of high-power lithium ion batteries.

The invention discloses a petuntse composition, ceramic and application, and relates to the technical field of ceramic. The ceramic disclosed by the invention is obtained by sequentially carrying out ageing treatment, sieving treatment, injection molding, airing, drying and sintering treatment on a petuntse composition. The petuntse composition comprises a ceramic waste material A, a ceramic waste material B and modified particles with gallium-coated cuprous oxide as a core and aluminum oxide as a shell in a specific proportion. And the components such as a high-entropy oxide solid solution generated by the reaction of hafnium oxide, tantalum pentoxide, niobium pentoxide, titanium dioxide, zirconium dioxide, chromium sesquioxide and carbon powder, and chromium heptacarbide are introduced, so that the ceramic prepared from the ceramic waste has excellent fracture toughness, bending strength, wear resistance, high temperature resistance and self-repairing ability. Therefore, the method has a wide application prospect.

The invention particularly relates to a photochromic TPU film and a preparation method thereof.The photochromic TPU film comprises a thermoplastic polyurethane elastomer and a photochromic material, the photochromic material is formed by mixing doped metal ions and Nb < 5 + > according to the molar ratio of 20-120 mol%, the doped metal ions are # imgabs0 # Fe < 3 + >, # imgabs1 # or # imgabs2 #, corresponding metal salt is added into the doped metal ions, the doped metal ions are doped metal ions, the doped metal ions are doped metal ions, the doped metal ions are doped metal ions, the doped metal ions are doped metal ions, the doped metal ions are doped metal ions, the doped metal ions are doped metal ions, the doped metal ions are doped metal ions, the doped metal ions are doped metal ions, and the doped metal ions are doped metal ions. The molar ratio of the doped metal to Nb is controlled to optimize the distribution concentration of the doped metal and particles, and TPU is adopted to improve the mechanical property of the film. According to the photochromic TPU film, a metal in-situ growth technology is adopted, the preparation process is simplified, dependence of high energy consumption and complex preparation means is avoided by in-situ growth of niobium pentoxide nanoparticles doped with metal elements in TPU, the production cost is greatly reduced, and the photochromic TPU film has good large-scale production potential.

The invention discloses a high-capacity porous niobium pentoxide material as well as a preparation method and application thereof, relates to niobium pentoxide as well as preparation and application thereof, and aims to solve the technical problems of low conductivity and slow ion diffusion of the conventional orthorhombic phase niobium pentoxide material. The material is formed by interconnection of niobium pentoxide matrix nanoparticles of 100-300 nm, secondary nanoparticles of 10-30 nm grow on the surface, and the material is in a raspberry-shaped multistage assembly morphology; the catalyst has mesopores with the pore diameter of 2-20 nm and the specific surface area of 15-45 m < 2 > / g; and the material has an orthorhombic phase niobium pentoxide structure and a carbon doping characteristic. The preparation method comprises the following steps: by taking a surfactant containing quaternary ammonium cations as a soft template, driving niobium salt and organic quaternary ammonium cations to be assembled by utilizing an electrostatic-coordination synergistic effect, and sintering at high temperature in an inert atmosphere. When used as a negative electrode of a lithium ion battery, the lithium ion battery can reach the capacity of 350 mAh / g under the current density of 0.1 A / g, and can be used in the field of fast-charge alkali metal ion batteries.

The invention provides a multi-modified lithium-rich manganese-based positive electrode material and a preparation method and application thereof, and the preparation method comprises the following steps: mixing a lithium-rich manganese-based precursor, a lithium source, lithium fluoride, niobium pentoxide and a fluxing agent to obtain a mixed material, and carrying out first sintering treatment on the mixed material to obtain a first sintered material; mixing the primary sintering material with a carbon source, and performing secondary sintering treatment to obtain a secondary sintering material; and mixing the secondary sintering material with lithium metaphosphate, and carrying out third sintering treatment to obtain the multi-modified lithium-rich manganese-based positive electrode material. The lithium-rich manganese-based positive electrode material is subjected to multiple modification, so that the problem of structural stability of a material body is solved, the interface effect is improved, surface passivation can be realized, and no extra resistance is generated for ion and electron transmission.

The invention discloses a preparation method of a negative temperature coefficient thermistor material for measuring the temperature of a new energy vehicle engine. The method uses raw materials such as calcium carbonate, cerium oxide, niobium pentoxide, and manganese dioxide as raw materials through processes of mixing and grinding, calcination, re-grinding, cold isostatic pressing, high-temperature sintering, and electrode coating processes to obtain a CaCeNbMnO7 composite thermistor material with a special structure, which has Ca2Nb2O7 as the main phase and a network conductive channel formed by the connection of structures such as cerium oxide and manganese oxide. The composite thermistor of the invention has the advantages of strong thermal cycle stability, high linearity, and large B value. The prepared CaCeNbMnO7 ceramic disc-shaped high-density ceramic material has good density, and the aging drift rate after aging at 500 °C for 400 h is less than 2%. It has excellent negative temperature coefficient characteristics and is suitable for use as a temperature sensing element for monitoring the temperature of a new energy vehicle engine.

The application discloses a preparation method of a sheet-shaped Nb element doped modified bismuth titanate catalyst material. 3‑x Nb x O 12 , wherein 0.15<=x<=0.40, the molar ratio of Bi, Ti and Nb is taken as bismuth oxide, titanium dioxide and niobium pentoxide; step two: the raw materials in step one and the mass ratio of the molten salt are mixed, then the mixture is put into a crucible and fully grinded to obtain a mixture; step three: the mixture prepared in step two is fired in a muffle furnace, and a light yellow product is obtained after cooling; step four: the light yellow product prepared in step three is washed with deionized water, filtered and dried to obtain a sheet-shaped Nb element doped bismuth titanate catalyst powder. The technology can significantly improve the structural uniformity, defect concentration and piezoelectric response activity of the material, greatly reduce the energy consumption and time cost, provides an efficient path for large-scale production of high-performance catalysts, and has a wide market prospect.

The invention discloses a microwave dielectric ceramic material and a preparation method thereof. The microwave dielectric ceramic material consists of the following components: a main crystalline phase raw material: 60-80% of BaTiO3 (barium titanate); a fluxing agent: 5%-15% of Bi2O3 (bismuth oxide); a doping agent: 0.1%-5% of Nb2O5 (niobium pentoxide); the additive comprises 1%-3% of MnO2 (manganese dioxide); 2%-5% of TiO2 (titanium dioxide); 1%-3% of Y2O3 (yttrium oxide); and 0.5%-2% of MoS2 (molybdenum disulfide). According to the microwave dielectric ceramic material and the preparation method thereof, the microwave dielectric ceramic material has extremely low dielectric loss (# imgabs0 # = 0.0022), so that the energy loss is greatly reduced in a microwave signal transmission process. In an actual communication system, such as a signal transmitting and receiving device of a 5G base station, a microwave element made of the material can effectively reduce attenuation of signals on a transmission path, the signals can reach a receiving end with higher strength and integrity, the communication quality is greatly improved, the bit error rate is reduced, and the service life of the microwave element is prolonged. And smooth proceeding of high-speed data services such as high-definition video transmission and rapid downloading of large files is ensured.

The invention discloses a CaCeNbWO8-based high-entropy negative temperature coefficient thermal sensitive ceramic material and a preparation method thereof, belongs to the field of negative temperature coefficient thermistors, and aims to expand the temperature zone range of a scheelite structure negative temperature coefficient thermal sensitive ceramic material. The material is prepared by mixing and firing raw materials including calcium carbonate, cerium dioxide, tungsten oxide, niobium pentoxide, samarium oxide, europium oxide, lanthanum trioxide, holmium oxide or dysprosium oxide according to a stoichiometric ratio, the chemical formula is (Ca1 / 3Ce1 / 3M1 / 3) (Nb1 / 2W1 / 2) O4, and M is Sm, Eu, La, Ho or Dy; the electrical property parameters of the thermal sensitive ceramic material with the negative temperature coefficient are as follows: B200 DEG C / 1100 DEG C is equal to 6081-7210 + / -1.8% K, rho1100 DEG C is equal to 2.87 * 10 < 3 >-4.09 * 10 < 3 > + / -1.37% omega.cm, and the applicable temperature range is 200-1100 DEG C. The material has a wide temperature range of 200-1100 DEG C, can maintain high sensitivity at a high temperature due to a large material constant B value, and shows excellent aging stability at 1000 DEG C. Through measurement, the resistance drift rate of the thermal sensitive ceramic material with the negative temperature coefficient is less than 3.49 + / -0.03% after the thermal sensitive ceramic material is aged at 1000 DEG C for 500 hours.

The invention provides a defluorination preparation method of niobium pentoxide, which comprises the following steps: (1) mixing a niobium hydroxide raw material with deionized water, and stirring until the niobium hydroxide raw material and the deionized water are uniformly mixed to obtain a slurry material; (2) uniformly smearing the slurry-like material on the inner surface of a hollow cylindrical crucible, and putting the hollow cylindrical crucible into the middle section of a glass tube of a microwave tube furnace; (3) inserting a thermocouple from one side of the glass tube, enabling the end part of the thermocouple to be in contact with the slurry-like material in the hollow cylindrical crucible, placing a water vapor generating device on the other side of the glass tube, and enabling a water vapor tube of the water vapor generating device to extend into the glass tube; and (4) starting the water vapor generating device and the microwave tube furnace, raising the temperature of the slurry-like material in the hollow cylindrical crucible to a target temperature, preserving heat for 20-40 minutes, naturally cooling to room temperature, and taking out to obtain niobium pentoxide. According to the method, residual fluorine can be efficiently removed while the purity of niobium pentoxide is guaranteed, the water consumption for washing is reduced, and the process period is shortened.

The present invention relates to a catalyst for degrading COD in wastewater and a preparation method thereof, comprising the following steps: a first step of preparing niobium pentoxide; a second step of preparing a pre-reaction solution: weighing octadecyltrimethylammonium chloride, thioacetamide, and distilled water, mixing them, stirring them uniformly, adding niobium pentoxide powder, and stirring them again until uniform to obtain a mixed solution A; weighing hafnium oxychloride octahydrate and distilled water, mixing them, stirring them thoroughly to obtain a mixed solution B; mixing the mixed solution B with the mixed solution A to obtain a mixed solution C; a third step of performing a hydrothermal reaction: pouring the mixed solution C into a reactor and heating it for reaction to obtain a product D; and a fourth step of high-temperature sintering to obtain niobium pentoxide / carbon-doped hafnium disulfide. The photocatalyst of the present invention is a composite product of carbon-doped hafnium disulfide and niobium pentoxide. It not only has good catalytic degradation efficiency for organic pollutants in wastewater, but is also not easily deactivated, has excellent reusability, and has a long service life.

The invention discloses a heteroepitaxial niobium pentoxide film and a preparation method and application thereof, and belongs to the technical field of film deposition. The preparation method comprises the following steps: placing a substrate and a target material in a vacuum system, bombarding the target material through pulse laser, and depositing on the surface of the substrate to obtain an initial heteroepitaxial niobium pentoxide film; and carrying out annealing treatment on the initial heteroepitaxial niobium pentoxide film to obtain the heteroepitaxial niobium pentoxide film. A pulsed laser deposition system is used for growing the single-crystal heteroepitaxial niobium pentoxide film, the film deposition speed is high, the repeatability is good, the purity and stoichiometric ratio of the prepared film and a target material can be kept highly consistent, process control can be carried out on the nanoscale, the thickness of the film is adjusted to the nanoscale, and the preparation method is simple and easy to implement. The target material can be reused, growth parameters can be flexibly regulated and controlled, the growth state of the thin film can be monitored in real time, and a high-quality heterogeneous interface structure can be obtained.

This invention discloses a ceramic clay composition, ceramics, and their applications, relating to the field of ceramic technology. The ceramics of this invention are obtained by sequentially processing the ceramic clay composition through a process of material conditioning, sieving, casting, air drying, oven drying, and sintering. The introduction of specific proportions of ceramic waste A and B, modified particles with a gallium-coated cuprous oxide core and an alumina shell, and high-entropy oxide solid solutions generated from the reaction of hafnium dioxide, tantalum pentoxide, niobium pentoxide, titanium dioxide, zirconium dioxide, chromium trioxide, and carbon powder, as well as chromium heptacarbonide, into the ceramic clay composition gives the ceramics prepared from the ceramic waste excellent fracture toughness, flexural strength, wear resistance, high-temperature resistance, and self-healing ability. Therefore, this invention has broad application prospects.

The invention provides a preparation method and an application method of a bismuth-based layered ferroelectric composite material, and belongs to the technical field of materials.The preparation method comprises the steps that bismuth nitrate pentahydrate, titanium dioxide, niobium pentoxide and sodium hydroxide are dispersed in deionized water to obtain a mixed solution; reacting the mixed solution at 200-240 DEG C for 20-30 hours to obtain a first reaction product; washing and drying the first reaction product to obtain Bi3TiNbO9; the preparation method comprises the following steps: adding Bi3TiNbO9 and lignin into deionized water, and mixing to obtain a mixture; reacting the mixture at 160-200 DEG C for 20-30 hours to obtain a second reaction product; and washing and drying the second reaction product, and calcining at 300-500 DEG C in a protective atmosphere for 1-4 hours to obtain the bismuth-based layered ferroelectric composite material. The method provided by the invention is simple in process and low in cost, and the prepared bismuth-based layered ferroelectric composite material has excellent photo-electro-catalysis performance and has a good photo-electro-catalysis degradation effect on plastics.