28results about How to "Evenly doped" patented technology

This invention discloses a zirconium-lanthanum bulk co-doped high-nickel ternary material, its preparation method, and a battery. The zirconium-lanthanum bulk co-doped high-nickel ternary material is a ternary cathode material with bulk co-doped zirconium and lanthanum; the chemical formula of the ternary cathode material is LiNi. x Co y Mn (1‑x‑y) O2, wherein 0.8≤x≤0.9, 0≤y≤0.1; the total molar amount of zirconium and lanthanum is 1%~5% of the total molar amount of nickel, cobalt and manganese. The zirconium-lanthanum bulk co-doped high-nickel ternary material provided by the present invention enhances the mechanical strength of the ternary material through the bulk co-doping of zirconium and lanthanum, suppresses cracking and pulverization of the ternary material during charge and discharge, and improves cycle stability; at the same time, the two elements Zr and La synergistically stabilize the lattice, reduce lithium-nickel mixing, suppress irreversible phase transformation and lattice oxygen precipitation, achieve dual stability of bulk phase and interface, and improve the consistency and stability of the zirconium-lanthanum bulk co-doped high-nickel ternary material.

The application discloses a preparation method of nitrogen-doped carbon-silicon nanofibers and application of the nitrogen-doped carbon-silicon nanofibers in a lithium ion battery negative electrode material, and belongs to the technical field of lithium ion battery negative electrode materials. The method comprises the following steps: mixing silicon nanoparticles and a carbon source, performing electrostatic spinning, stabilization treatment and carbonization treatment, and obtaining carbon-silicon nanofibers; and then mixing the carbon-silicon nanofibers with a nitrogen source, performing heat treatment under an inert atmosphere, making nitrogen elements doped into a carbon skeleton, and obtaining nitrogen-doped carbon-silicon nanofibers. The material obtained by the application is a one-dimensional nanofiber structure, silicon particles are uniformly wrapped in carbon fibers, and nitrogen elements are uniformly distributed in the carbon skeleton. The method can realize uniform nitrogen doping while maintaining the microstructure of the material, and significantly improves the electronic conductivity and interface stability of the material. The material obtained by the application is used as a lithium ion battery negative electrode, and exhibits high reversible capacity and excellent cycle stability.

This invention relates to a tungsten-doped tin dioxide nanopowder, its preparation method, and its application in semiconductor-type gas-sensitive elements. The method for preparing the tungsten-doped tin dioxide nanopowder includes the following steps: dissolving a soluble tungsten compound and a soluble tin compound in an aqueous solution containing a surfactant, and adding a complexing agent to obtain a homogeneous metal ion mixed solution; adding a precipitant to the mixed solution under stirring conditions to adjust the pH to 2-6, causing a metal hydroxide precursor to precipitate; aging, solid-liquid separation, washing, and drying the precipitate to obtain a precursor powder; adding a dispersant to the precursor powder and mixing evenly; and calcining to obtain the tungsten-doped tin dioxide nanopowder. The tungsten-doped tin dioxide nanopowder of this invention can be used in the preparation of semiconductor-type gas-sensitive sensors, ultraviolet detectors, lithium-ion battery anode materials, catalysts, or transparent conductive films.

The application belongs to the technical field of all-solid-state lithium-sulfur battery materials, and relates to a lithium sulfide nano composite positive electrode material with high reaction kinetics and a preparation method and application thereof. The application aims to solve the deficiencies of the lithium sulfide positive electrode material in ion and electron conductivity, reduce the activation barrier of the lithium sulfide positive electrode material, improve the battery redox kinetics, and further improve the rate performance and cycle capacity of the battery. The lithium sulfide nano composite positive electrode material is prepared by using an in-situ synthesis method, the obtained composite material has rich metal atom crystals embedded in the lithium sulfide matrix, and a layer of amorphous carbon is uniformly coated on the surface. The finally obtained lithium sulfide nano composite positive electrode material exhibits high reversible capacity and excellent rate performance. The application has the characteristics of uniform coating and simple process, is suitable for large-scale production, and has a wide application prospect in the field of all-solid-state lithium-sulfur batteries.

The utility model relates to the technical field of gallium oxide crystal growth, and discloses a crucible structure for growing a gallium oxide single crystal by a VB method, which comprises a crucible shell, a seed crystal cavity, a diameter-expanding cavity, a diameter-reducing cavity, a shoulder-expanding cavity and an equal-diameter cavity, the seed crystal cavity, the diameter-expanding cavity, the diameter-reducing cavity, the shoulder-expanding cavity and the equal-diameter cavity are arranged in the crucible shell, the seed crystal cavity is arranged at one end of the crucible shell, and the diameter-reducing cavity is arranged at the other end of the crucible shell. One end of the seed crystal cavity is closed, the other end of the seed crystal cavity is connected with the diameter-expanding cavity, the diameter-expanding cavity is connected with the diameter-reducing cavity, the diameter-reducing cavity is connected with the shoulder-expanding cavity, the shoulder-expanding cavity is connected with the equal-diameter cavity, and the other end of the equal-diameter cavity is open. Through reasonable design of a gallium oxide growth technology, the crucible shell, the seed crystal cavity, the diameter-expanding cavity, the diameter-reducing cavity, the shoulder-expanding cavity and the equal-diameter cavity are adopted, so that gallium oxide crystals can be separated from the crucible wall during growth and cooling, dislocation proliferation and twin crystal structures are not easy to appear, the crystal dislocation density is reduced, and the performance of a semiconductor chip is improved. The crucible structure can be used for preparing cylindrical gallium oxide single crystals with low dislocation density.

The application relates to a highly-ordered porous sulfur / oxygen co-doped carbon sphere and a preparation method and a potassium ion battery thereof, and belongs to the technical field of battery materials. The application discloses a preparation method of a highly-ordered porous sulfur / oxygen co-doped carbon sphere. The carbon sphere is prepared by mixing sulfur powder and resin material, the prepared carbon sphere is uniformly doped with atoms, the pore size distribution is uniform, the number of potassium storage sites is relatively large, and the carbon sphere can be applied to a potassium ion battery. The application further discloses a potassium ion battery. The active material of the potassium ion battery comprises the highly-ordered porous sulfur / oxygen co-doped carbon sphere. The potassium ion battery can be a half battery assembled by a negative electrode material containing the highly-ordered porous sulfur / oxygen co-doped carbon sphere and metal potassium. The potassium ion battery can also be a full battery assembled by the negative electrode material containing the highly-ordered porous sulfur / oxygen co-doped carbon sphere and a prussian blue positive electrode material.

The invention relates to the technical field of nano materials, in particular to a preparation method of a Zn-based bimetal MOFs material and application of the Zn-based bimetal MOFs material as a medical drug carrying material. The preparation method comprises the following steps: preparing Zn, Mn and a ligand according to a molar ratio of 1: 1: (72-80), and mainly comprises the steps of preparation of metal salt solutions, coordination polymerization reaction, separation and purification, and drying. The process for preparing the Zn-based bimetallic MOFs material is simple and environmentally friendly, the obtained product has the excellent performance of being small in particle size, regular and stable, and the material loaded with doxorubicin hydrochloride has high loading rate and has potential clinical conversion value.

A preparation method of high-compaction titanium-doped iron phosphate, comprising S1, preparing a phosphoric acid solution, a hydrogen peroxide solution, a Ti salt solution, a phosphorus salt solution and a ferrous salt solution; S2, mixing the Ti salt solution and the ferrous salt solution to obtain a titanium-iron salt solution; mixing the phosphoric acid solution and the phosphorus salt solution to obtain a phosphorus source solution; S3, adding the titanium-iron salt solution into a reaction kettle and adding the hydrogen peroxide solution; S4, adding the phosphorus salt solution into the reaction kettle to obtain a yellow slurry; S5, after the slurry color changes to white after temperature rising, a white slurry is obtained; S6, performing solid-liquid separation on the white slurry to obtain an iron phosphate dihydrate filter cake; S7, drying and calcining the iron phosphate dihydrate filter cake to obtain a battery-grade anhydrous iron phosphate doped with Ti. The present application prepares titanium-doped iron phosphate in one step, controls the molar ratio of iron elements to total phosphorus, phosphorus ammonium and phosphoric acid in the reaction system, controls the pH of the reaction system, ensures the retention of Ti elements in the finished product and regulates the iron-phosphorus ratio within a specified range.

The invention relates to the technical field of lithium ion batteries, and discloses a high-nickel ternary positive electrode material and a preparation method and application thereof, and the preparation method comprises the following steps: mixing and sintering a nickel-cobalt-manganese precursor, a lithium source, niobium salt and fused salt. According to the preparation method of the high-nickel ternary positive electrode material provided by the invention, the niobium salt and the molten salt form a liquid phase environment at a relatively low temperature, and the niobium element can efficiently enter a crystal lattice, so that uniform bulk phase doping in a real sense is realized, and the electrochemical stability and the thermal stability are improved; meanwhile, the niobium doping can ensure the rapid and uniform transmission of the lithium source, so that the lithiation is more sufficient, and the lithium-nickel mixed arrangement caused by lithium deficiency is reduced in dynamics.

The utility model relates to the technical field of semiconductor material preparation, and disclose a kind of N type high-purity silicon target material red phosphorus doping device, including reaction chamber, rotating support mechanism, phosphorus vapor injection system, partition temperature control module, gas circulation unit and intelligent control system, reaction chamber adopts quartz material double-layer structure, the inner wall of reaction chamber is provided with silicon nitride coating, the outer wall of reaction chamber is provided with vacuum pump set, rotating support mechanism includes high-temperature ceramic support, magnetic fluid seal shaft and brushless motor, high-temperature ceramic support is connected with the output end of brushless motor by magnetic fluid seal shaft, by integrated reaction chamber, rotating support mechanism, phosphorus vapor injection system, partition temperature control module, gas circulation unit and intelligent control system, by rotating dynamic doping, intelligent temperature control and waste gas circulation technology, significantly improve the uniformity of doping and raw material utilization rate, realize the efficient, uniform doping of silicon target material.

This invention discloses a Ni-Sn / NC(P) electrocatalyst, its preparation method, and its application, relating to the field of electrochemical CO2 reduction raw material technology. In this invention, zinc nitrate hexahydrate, 2-methylimidazolium, and polyvinylpyrrolidone are separately placed in methanol and stirred. After stirring, they are mixed and stirred again, centrifuged, washed, and vacuum dried. Nickel chloride hexahydrate, tin tetrachloride pentahydrate, ethanol, and the obtained ZIF-8@PVP precursor are mixed, heated and stirred in a water bath, centrifuged, washed, and vacuum dried. The obtained Ni-Sn / ZIF-8(PVP) powder is calcined in an inert atmosphere, and after calcination, cooled to room temperature to obtain the Ni-Sn / NC(P) electrocatalyst. This invention provides a diatomic electrocatalyst with regular morphology, uniform elemental distribution, and excellent electrochemical performance for the efficient electroreduction of carbon dioxide to carbon monoxide. Its preparation method is controllable, uses simple equipment, has high conversion efficiency, and is low in cost.

The application discloses a preparation method of manganese iron phosphate and application thereof, and the preparation method comprises the following steps: S1, mixing an iron-manganese-phosphorus mixed solution, an oxidizing agent and a pH regulator to obtain a mixed slurry; S2, taking 20%-60% of the volume of the mixed slurry at 60-100 DEG C for 2-6 hours, then adding the remaining mixed slurry for heat preservation reaction, impurity removal and calcination to obtain manganese iron phosphate. The monohydrate manganese iron phosphate prepared by the embodiment of the application has olivine-shaped primary particles, the olivine-shaped primary particles are orderly stacked to form secondary particles, the process is simple and stable, and iron and manganese elements are uniformly doped.

The invention belongs to the technical field of optical communication, and particularly discloses a preparation method of an ultra-low attenuation optical fiber and the ultra-low attenuation optical fiber, and the preparation method comprises the steps: S1, preparing a fluorine-doped sleeve with non-uniform fluorine distribution through employing an external vapor deposition technology; s2, stretching and corroding the fluorine-doped sleeve to obtain an inner cladding with a predetermined aperture; s3, SiO2 is deposited in the inner cladding layer by using an in-tube vapor deposition process, alkali metal doping is performed to form a core layer, the inner cladding layer with the core layer is melted and shrunk into a rod shape, and a rod-shaped structure is obtained; s4, preparing an outer cladding layer outside the rod-shaped structure through an external vapor deposition process, drying the rod-shaped structure with the outer cladding layer, and solidifying in a fluorine-containing atmosphere to obtain an optical fiber preform; and S5, drawing the optical fiber preform to form the optical fiber. According to the preparation method, external chemical vapor deposition and in-tube vapor deposition are utilized to achieve better optical fiber profile matching and viscosity matching.

This invention relates to a doped yttrium oxide flake powder, its preparation method, and its applications. The method uses 0.2-0.4 M Y(NO₃)₂. 3 ) 3 ·6H 2 O solution as Y 3+ Source, then add MgCl to the solution 2 and Al(NO 3 ) 3 ·9H 2 O was used as a dopant. After adjusting the pH of the mixed solution to 8-10, a hydrothermal reaction was carried out at 170-200°C for 9-15 hours to achieve uniform distribution of the dopant in the yttrium oxide lattice. Finally, the powder was calcined at 600-700°C for 3-5 hours to improve the structural stability and properties of the material. The synthesized doped yttrium oxide powder had a plate-like morphology with a particle size between 5-25 micrometers, and the final product composition included Y. 2 O 3 MgAl 2 O 4 And Y-Al-O compounds. Compared with traditional physical doping methods, the preparation method of this invention not only achieves a more uniform doping effect, but also shows significant advantages in terms of energy consumption, cost, and particle size control. The doped yttrium oxide obtained by this method has performance superior to or equivalent to high-purity yttrium oxide, providing a new avenue for the further application and development of yttrium oxide.

The invention discloses a phosphorus-doped double-vacancy heterostructure material, a preparation method and application, and belongs to the technical field of electrocatalysis, polyacid is used as a precursor to prepare P-MoS2 rich in sulfur vacancies on carbon cloth through hydrothermal treatment, then part of MoS2 is converted into MoO2 in situ through heat treatment, and a P-MoS2 / MoO2 heterostructure is constructed. Abundant oxygen vacancies are generated in the thermal conversion process. Rich vacancy defects and heterogeneous interfaces in the constructed catalyst promote electron transfer and adsorption of active substances, charge transfer kinetics is improved, and more reaction active sites are provided for water cracking; the vertically crossed nanosheet network on the carbon cloth is beneficial to charge transport, reactant permeation and gas diffusion. Various components in the catalyst synergistically promote the water electrolysis process, and a novel advanced, economical, efficient and stable electrode material is provided for catalytic application.

The application discloses a preparation method of a lithium nickel cobalt manganese oxide ternary positive electrode material and belongs to the technical field of lithium ion batteries. The lithium nickel cobalt manganese oxide ternary positive electrode material is prepared by the following steps: synthesizing Y-containing nickel cobalt manganese hydroxide by adopting a co-precipitation method, then doping N and synthesizing the lithium nickel cobalt manganese oxide material by adopting a high-temperature solidification sintering method, and then coating N-containing yttrium titanate (N-YTO) on the surface of the lithium nickel cobalt manganese oxide material by adopting a sol-gel method. The preparation process is simple and easy to operate, Y and N are uniformly doped in the bulk phase, the N-YTO coating layer is uniformly distributed on the surface of the material, the N-YTO coating layer can effectively inhibit the occurrence of internal micro-cracks of particles, electrolyte corrosion and side reactions, can improve the diffusion efficiency of lithium ions and the structural stability, and can further improve the voltage platform, the cycle life, the rate performance and the thermal safety of the lithium nickel cobalt manganese oxide ternary positive electrode material, and the lithium nickel cobalt manganese oxide ternary positive electrode material is suitable for large-scale production.

The invention discloses a molybdenum-rhenium alloy and a preparation method thereof. Belongs to the alloy field. The preparation method of the molybdenum-rhenium alloy provided by the invention comprises the following steps: smelting molybdenum-rhenium-lanthanum oxide alloy powder by adopting a vacuum electric arc to prepare a molybdenum-rhenium alloy casting blank; machining the molybdenum-rhenium alloy casting blank to obtain a molybdenum-rhenium alloy plate; the molybdenum-rhenium alloy plate is subjected to pre-strain plastic deformation treatment at the temperature of 25-1500 DEG C, and the molybdenum-rhenium alloy is obtained; the pre-strain plastic deformation treatment comprises the following steps: unloading to a zero stress state after applying 0.25%-2.5% of pre-strain quantity each time, and circulating for 100-1000 times. According to the molybdenum-rhenium alloy for improving the alpha texture strength through the deformation cumulative effect, the strength of the molybdenum-rhenium alloy with the low rhenium content is remarkably improved, the dosage dependence of rhenium resources is greatly reduced, and the production cost is reduced.

The invention discloses a freeze-drying preparation method of second-phase particle dispersion nano tungsten-nickel-iron composite powder, which comprises the following steps: 1, adding rare earth nitrate, a salt solution and a surfactant into deionized water, and carrying out ultrasonic treatment to form a uniform precursor mixed solution; 2, performing freeze drying after pre-freezing treatment to obtain precursor powder; and thirdly, the precursor powder is subjected to calcination treatment and a two-step reduction process, and second-phase particle dispersion nanometer tungsten-nickel-iron composite powder is obtained. According to the preparation method, the precursor powder with the submicron particle size and highly concentrated particle size distribution is prepared by combining rapid pre-freezing with a freeze-drying process, and high-purity and high-uniformity compounding of tungsten-nickel-iron and second-phase particles is realized by combining subsequent calcination and reduction; the second-phase oxide particle dispersion nano tungsten-based composite powder with high purity and good uniformity is obtained, controllable preparation of superfine nano powder is achieved, and the method has good process amplification potential and is suitable for the field of powder preparation engineering.

The invention discloses a nitrogen-doped porous carbon material which is prepared by taking a nitrogen-containing compound as a nitrogen source and EDTA (Ethylene Diamine Tetraacetic Acid) metal salt as an activating agent and a carbon source through pyrolysis. Through the synergistic effect of the nitrogen source and the EDTA metal salt, carbon skeleton construction, nitrogen atom in-situ doping and pore self-activation are synchronously achieved, the problems that an existing nitrogen-doped porous carbon preparation process is complex, and adsorption performance and selectivity are difficult to consider at the same time are solved, the material can be efficiently used for CO2 capture in industrial flue gas and other scenes, and the application prospect is wide. The method has a wide industrial application prospect.

The application provides a preparation method of a zinc-doped lithium nickel cobalt manganese oxide positive electrode material, and the preparation method comprises the following steps: S1, mixing a nickel source, a cobalt source, a manganese source and a zinc source to obtain a mixed salt solution; S2, in an inert atmosphere, mixing the mixed salt solution and a precipitant solution by simultaneously dropping, continuously dropping the precipitant solution to adjust the pH value of the mixed solution to 10-11, performing a co-precipitation reaction, and obtaining a precursor slurry; S3, adjusting the pH value of the precursor slurry in step S2 to 7-8, performing solid-liquid separation, and drying the precipitate to obtain a precursor; and S4, mixing the precursor in step S3 with a lithium source, and sintering to obtain the zinc-doped lithium nickel cobalt manganese oxide positive electrode material. The method provided by the application can reduce the surface residual alkali content of the positive electrode material, and excellent cycle stability is obtained.

This invention belongs to the field of electrocatalyst technology, and specifically relates to a graphene-based sheet-like porous catalyst, its preparation method, and its application. The preparation method includes: separately preparing an aqueous dispersion of graphene oxide and an aqueous dispersion of nano-melamine-formaldehyde resin, mixing them, and stirring to obtain a mixed dispersion; mixing the mixed dispersion with a hydroxyl-containing compound, adjusting the pH to weakly alkaline, stirring, concentrating, and drying to obtain a dried product; and subjecting the dried product to high-temperature pyrolysis. This method can prepare a sheet-like nitrogen-doped carbon-based non-noble metal electrocatalyst with stable mechanical properties, abundant pore structure, and high nitrogen content. It exhibits excellent electrochemical catalytic performance, has a simple preparation method, mild reaction conditions, and can achieve uniform nitrogen doping.

This invention provides a gradient doping mixing device for high-energy-density, high-efficiency anode materials, belonging to the field of materials processing technology. It includes a main body structure comprising a shell, a feeding funnel fixedly connected to the top of the shell, a feeding trough on one side of the shell, a fixing trough on the other side of the shell, and a feeding assembly fixedly connected to the inner wall of the feeding trough. A stirring mechanism includes a connecting trough on the inner wall of the shell and a stirring chamber welded to the surface of the connecting trough. This invention utilizes a three-dimensional mixing structure formed by the first and second stirring blades of the stirring assembly, with through-holes dispersing the material's impact force and enhancing turbulence. A trapezoidal block in the main body guides the material to the feeding chute, and the feeding assembly drives a baffle plate via a screw to precisely control the flow rate at the outlet, reducing material residue. The fixing trough and limiting trough ensure the stability of the equipment operation, and the overall structural design improves the production efficiency of the anode materials.

The application relates to a transition metal doped thermal injection type colloidal quantum dot and a preparation method thereof, and belongs to the technical field of quantum dot material synthesis. The method comprises the following steps: 1) mixing tellurium powder and tri-n-octylphosphine, heating to 140-160 DEG C under a protective atmosphere, and keeping the temperature for 20-40 min to obtain a tellurium precursor; 2) mixing silver acetate, a transition metal acetate and dodecanethiol, heating to 115-140 DEG C under a protective atmosphere, adding the obtained tellurium precursor, reacting for 10-20 min, and cooling to room temperature to obtain a quantum dot stock solution; and 3) separating and purifying the obtained quantum dot stock solution to obtain transition metal doped silver telluride quantum dots. The method is simple in operation, uniform in doping, and high in controllability; impurity energy levels are introduced under the premise of not damaging the crystal lattice structure through transition metal doping, the emission spectrum of the quantum dots is widened, wide spectrum light emission from visible light to near infrared is realized, and the optical performance and stability are effectively improved; and the obtained quantum dots can be widely applied to the fields of infrared detection, biological imaging and optoelectronic devices.

The application discloses a Se-doped sulfide solid electrolyte and a preparation method thereof, and relates to the technical field of battery materials. The preparation method comprises the following steps: mixing a selenium source, a complexing agent and a first organic solvent to obtain a first mixed solution; mixing a lithium source, a nonmetal source and a second nonpolar organic solvent, heating the obtained second mixed solution to a first preset temperature, then adding the first mixed solution, and stirring for a first preset time; continuously heating to a second preset temperature and stirring for a second preset time; drying the obtained coprecipitate, and annealing at 300-400 DEG C to obtain the Se-doped sulfide solid electrolyte; the boiling point of the first organic solvent is less than or equal to the first preset temperature, and the boiling point of the second nonpolar organic solvent is less than or equal to the second preset temperature. The application realizes uniform doping of Se elements by adopting a double-solvent gradient evaporation technology combined with low-temperature annealing, and the prepared Se-doped sulfide solid electrolyte has higher ionic conductivity and air stability compared with undoped electrolyte.

The invention discloses a non-transfer rare earth doped tungsten diselenide heterojunction photoelectric device and a preparation method thereof, and belongs to the technical field of semiconductor photoelectric devices. The method comprises the following steps: carrying out cleaning and hydrofluoric acid activation treatment on a silicon substrate on a silicon-based insulator; the preparation method comprises the following steps: taking tungsten trioxide, erbium chloride, sodium chloride and selenium as precursors through a one-step chemical vapor deposition method, growing a single crystal erbium-doped tungsten diselenide film on an activated substrate silicon surface in an in-situ epitaxial growth manner, and directly constructing an erbium-doped tungsten diselenide / silicon Van der Waals heterojunction; and finally, preparing the electrode through photoetching, developing, metal deposition and stripping processes. According to the method, interface pollution caused by a traditional transfer process is thoroughly avoided, and high-concentration uniform erbium doping is realized by using a sodium chloride fluxing agent. The prepared heterojunction device has an atomic-scale clean interface and shows excellent photoelectric performance, the process is compatible with a complementary metal oxide semiconductor process, and a reliable platform is provided for high-performance silicon-based photoelectric integration.

The invention discloses a preparation method of SiBCN aerogel based on triethanolamine borate molecular-level doping, and belongs to the field of high-temperature-resistant thermal protection materials. According to the method, triethanolamine borate is taken as a boron source and a nitrogen source, molecular-level uniform doping of boron and nitrogen elements is realized through a sol-gel process, and the SiBCN aerogel is obtained after aging, modification and drying. The fiber felt can also be immersed in the sol, and gelation post-treatment is carried out synchronously, so that the composite material is prepared. High-bond-energy chemical bonds are generated through boron-nitrogen source molecular-level in-situ doping, shrinkage sintering of the material at high temperature is inhibited, and excellent heat insulation performance is kept. After the fiber felt is introduced, the mechanical property is greatly improved, the compressive strength of 50% compressive deformation is 0.2-0.5 MPa, the volume shrinkage rate of the material at 1000-1100 DEG C is extremely low (1-3%), meanwhile, the material has the thermochromic function that the color is deepened along with the increase of heating time, and a new material solution is provided for extreme environment thermal protection and post-disaster thermal history tracing.

This invention belongs to the field of lithium-ion battery material technology, specifically relating to a high-nickel single-crystal ternary cathode modified material and its preparation method. The method includes: ball milling a high-nickel single-crystal ternary precursor, lithium hydroxide monohydrate, and a cerium-tantalum co-doped lithium molybdenum oxyfluoride compound, followed by pre-sintering and high-temperature calcination under an oxygen atmosphere to obtain single-crystal powder particles; then mixing the single-crystal powder particles with a calcium-doped lithium boron phosphorus oxynitride compound, drying, and holding under a nitrogen atmosphere before sieving. The cerium-tantalum co-doped lithium molybdenum oxyfluoride compound is prepared by ball milling, drying, and segmented sintering of lithium carbonate, cerium oxide, tantalum oxide, molybdenum oxide, and lithium fluoride in a protective powder; the calcium-doped lithium boron phosphorus oxynitride compound is prepared by ball milling, segmented sintering, and ball milling and sintering with lithium nitride under nitrogen protection. This invention significantly improves the structural stability and electrochemical performance of the high-nickel single-crystal ternary cathode material.

This application relates to a uniformly doped rod-shaped gallium nitride powder and its preparation method. The gallium nitride powder has a regular morphology, uniform size, high purity, and high crystallinity, and can be used as a key functional material for high-end optoelectronic devices, power semiconductors, and advanced packaging. The method uses metallic gallium as raw material and introduces dopant simultaneously during the hydrothermal synthesis of gallium oxyhydroxide precursor, so that the target element is embedded in situ during the lattice construction stage, achieving atomic-level uniform bulk doping. This fundamentally avoids the problems of uneven doping, "doped islands," concentration gradients, and surface enrichment caused by traditional post-doping methods. The obtained precursor is directly converted into uniformly doped rod-shaped gallium nitride powder by a one-step high-temperature nitridation. This process is short, simple to operate, and environmentally friendly, effectively solving the problems of uneven doping, poor crystallinity, severe agglomeration, and complex processes in the prior art, and providing an efficient and scalable technical path for the controllable preparation of high-performance gallium nitride powder.