657 results about "Oxygen atmosphere" patented technology

The invention discloses an asphalt-based hard carbon negative electrode material for a sodium-ion battery and a preparation method of the asphalt-based hard carbon negative electrode material, and belongs to the technical field of negative electrode materials for sodium-ion batteries. The hard carbon negative electrode material is prepared from the following raw materials in parts by weight: 30-80 parts of asphalt, 10-30 parts of a cross-linking agent and N, N-dimethylformamide as a solvent. The preparation method comprises the following steps: S1, carrying out crushing, ball milling and sieving on the asphalt to obtain powder with the particle size of 10 [mu] m; s2, uniformly mixing the powder, N, N-dimethylformamide and a cross-linking agent to obtain a cross-linked substance; s3, carrying out pre-oxidation treatment on the cross-linked product in an oxygen atmosphere; and S4, performing high-temperature carbonization treatment on the low-temperature pre-oxidized cross-linked product in an inert atmosphere to obtain the asphalt-based hard carbon material. The organic cross-linking agent is introduced to initiate oxidation cross-linking of the asphalt, so that the asphalt is converted into a thermosetting precursor from a thermoplastic precursor, and the high-performance asphalt-based hard carbon material for the sodium-ion battery is prepared.

The invention discloses a metal self-dispersed low-carbon alkane dehydrogenation catalyst as well as a preparation method and application thereof. The catalyst is composed of a molecular sieve carrier, metal particles of main active components Ru, Rh, Pd, Ir, Pt and Au, auxiliary components Fe, Co, Ni, Cu, Zn, Ga, In, Ge, Sn, Mn, Zr, V, Cr, Ti, Nb, Mo, Y, W, Pb, Sc, Bi, Sb, La and Ce, and alkali metal components Na, Mg, K, Ca and Cs. Firstly, the synthesized molecular sieve is subjected to high-temperature activation heat treatment, so that rich defect sites are generated; and mixing the activated molecular sieve with metal particles, and finally carrying out high-temperature treatment on the mixture in an oxygen atmosphere to prepare the stable molecular sieve loaded metal cluster. The obtained catalyst shows excellent catalytic activity and regeneration performance. The active metal particles are used as raw materials, the step of converting metal particle powder into salt is reduced, a physical mixing method is adopted, the preparation process of the catalyst is simpler, and the economic cost is lower.

The invention relates to the technical field of electro-catalysis oxygen evolution, and particularly discloses a nickel-molybdenum foam composite oxygen evolution electro-catalysis material with high-valence nickel induced by molybdate radicals and a preparation method of the nickel-molybdenum foam composite oxygen evolution electro-catalysis material aiming at the problem that an existing oxygen evolution electro-catalysis material is insufficient in comprehensive performance or poor in performance stability. Soaking in a NaCl aqueous solution, and taking out; s2, mixing the nickel-molybdenum alloy foam with a K3 [Fe (CN) 6] aqueous solution, heating, and carrying out a hydrothermal reaction; and S3, finally, the nickel-molybdenum alloy foam is placed in the air or oxygen atmosphere and heated to 350-450 DEG C, heat preservation treatment is conducted for 2 h, and the nickel-molybdenum foam composite oxygen evolution electro-catalysis material is obtained. Molybdate anions are adopted as a sustainable induction source to be coupled with a NixOy / Fe3O4 heterogeneous interface, integrated construction is achieved on a nickel-molybdenum foam framework, and the nickel-molybdenum foam composite material has the advantages of being low in overpotential, high in stability, high in activity, high in binding force and long-term in durability and meanwhile being simple in process, easy to amplify on a large scale and the like.

The invention relates to a method for preparing a hard carbon material from carbon dot heterogeneous cross-linked bituminous coal, a coal-based hard carbon material and application. The preparation method comprises the following steps: (1) soaking pretreated bituminous coal in an acid solution, washing to be neutral, and drying to obtain dry pulverized coal; (2) dispersing the carbon dots in an alcohol solvent for ultrasonic treatment to obtain a dispersion liquid; (3) mixing the dried pulverized coal obtained in the step (1) and the dispersion liquid obtained in the step (2), mechanically stirring, and drying to obtain a mixture; (4) performing low-temperature heating crosslinking on the mixture obtained in the step (3) in an oxygen-containing atmosphere so as to obtain a heterogeneous crosslinking product; and (5) performing high-temperature carbonization on the heterogeneous cross-linked product in an inert atmosphere to obtain the coal-based hard carbon material. The coal-based hard carbon material can be used as a sodium ion battery / potassium ion battery negative electrode, and has excellent sodium / potassium storage performance.

The invention discloses a method for separating and recycling a silver-copper composite material through selective interface oxidation. The method comprises the following steps that the material is crushed and sheared, and a crushed material is obtained; the crushed material is pretreated and then fed into an oxidation fluidized bed, an internal oxidation reaction is conducted in a gas phase at the temperature of 400-700 DEG C and the oxygen pressure of 0.2-0.6 MPa, the reaction time is 20-60 h, and a high-temperature material is obtained; quenching the high-temperature material to generate stress cracks on an oxidation interface to obtain a cooled material; and stripping the cooled material under the mechanical action to obtain a recycled copper material and a recycled silver material, oxidizing the electrical contact material or leftover materials of the electrical contact material in the oxygen atmosphere to oxidize an interface between the silver-copper composite materials to form an oxidation film, separating the two materials of the silver-copper composite materials under the quenching and mechanical actions, and then, obtaining the recycled copper material and the recycled silver material. The method is high in recovery rate, high in recovery purity and environment-friendly.

The invention relates to a ternary positive electrode material with a core-shell structure and a preparation method and application thereof, and the method comprises the following steps: S1, mixing a lithium source with a nickel-cobalt-manganese hydroxide ternary precursor, and carrying out first heat treatment on the obtained mixture in a first oxygen-containing atmosphere to obtain a first material; s2, enabling the first material to be in contact with a solution containing ammonium salt, performing impregnation, and performing second heat treatment on an obtained solid in a second oxygen-containing atmosphere; the temperature of the first heat treatment is lower than that of the second heat treatment. The ternary positive electrode material prepared by adopting the method disclosed by the invention is relatively low in residual alkali content, and relatively good thermal stability and electrochemical performance can be obtained when the ternary positive electrode material is used as a positive electrode material of a lithium ion battery.

The invention relates to a method for recycling polyethylene plastic through catalytic oxidation cracking, and belongs to the technical field of plastic recycling. The method comprises the following steps: mixing a Co / Al2O3 catalyst, polyethylene plastic and water, and carrying out a catalytic reaction in an oxygen-containing atmosphere at a set temperature, so that the polyethylene plastic is converted into binary acid, thereby obtaining a reaction solution. The low-price Co / Al2O3 catalyst is applied to catalytic oxidation cracking of the polyethylene plastic, the polyethylene plastic is converted into the binary acid, the yield of the binary acid is stabilized at 70% or above and reaches 115% at most, and the Co / Al2O3 catalyst is low in price and low in cost. The low-cost and low-energy-consumption improvement of the yield of the binary acid converted from the polyethylene plastic through catalytic oxidation cracking is fully realized, and a new way is provided for the high-value conversion of the polyethylene plastic.

The invention provides a method for manufacturing a terbium-dysprosium-iron giant magnetostrictive alloy based on three-dimensional photocuring molding, which comprises the following steps of: firstly, preparing three-dimensional photocuring molding slurry, adopting photosensitive resin as a matrix, and matching with a metal organic chelating agent containing terbium-dysprosium-iron giant magnetostrictive alloy component to enhance the uniform distribution of metal powder so as to ensure the printing precision and the material stability; secondly, the resin and the chelating agent are removed through heat treatment degreasing, the degreasing process is controlled by controlling the heating rate, and structural collapse is avoided; decarburization is carried out in a low-oxygen atmosphere, so that the purity of the alloy is improved, and the structural integrity before sintering is ensured; then reduction treatment is performed to improve the structural stability and purity; and finally, high-temperature sintering is carried out under the assistance of a magnetic field, grain orientation and magnetic domain arrangement are optimized, and the magnetostrictive effect and the force-magnetic energy conversion efficiency are improved. According to the method, three-dimensional light curing forming and magnetic field auxiliary heat treatment are combined, and the risk of structural damage in the printing process of the terbium dysprosium iron giant magnetostrictive alloy is practically and effectively avoided.

The invention provides sintering flue gas denitration activated carbon and a preparation method thereof.The preparation method comprises the steps that coal-based activated carbon raw material powder and an aqueous solution of a nitrogen-containing compound and a phosphorus-containing compound are evenly mixed, impregnated and dried, and a nitrogen-phosphorus co-doped precursor is obtained; blending the catalytic components to obtain raw material strips; primarily forming pores, and activating for the first time in a water vapor atmosphere; carrying out secondary loading and pore regulation, and carrying out secondary activation to obtain a secondary carbon body; and carrying out heat treatment on the secondary carbon body in an oxygen-containing atmosphere to convert the loaded metal precursor into a metal oxide. According to the invention, through a cascade catalytic network constructed by nitrogen and phosphorus doping and titanium, tungsten and vanadium oxides and an optimized pore channel formed by step-by-step activation of water vapor and carbon dioxide, the denitration efficiency of the catalyst breaks through 80% and is far higher than that of common activated carbon. The sintering flue gas denitration system has high activity and high stability, can greatly reduce the series number of denitration towers, obviously reduces the system resistance and operation energy consumption, and provides an efficient scheme for solving the problems of low sintering flue gas denitration efficiency and high cost.

The invention belongs to the field of battery materials, and particularly relates to a regenerated graphite fast charging material and preparation and application thereof.The preparation method comprises the steps that waste graphite is subjected to first-stage plasma treatment in an oxygen-containing atmosphere in advance and then subjected to second-stage plasma treatment in an ammonia-containing atmosphere, and first-stage modified graphite is obtained; performing ultrasonic treatment on the first-stage modified graphite in a modification liquid containing an N modifier to obtain second-stage modified graphite; performing first-stage polymerization on the second-stage modified graphite in a solution A containing a monomer 1 in a formula 1 and an initiator in advance, and then performing second-stage polymerization on the second-stage modified graphite in a solution B containing a monomer 2 and an oxidizing agent to prepare the regenerated graphite quick-charging material, the monomer 2 comprises at least one of a formula 2 and a formula 3. The method provided by the invention can strengthen ion and electron conduction pathways of the regenerated material, improve the transmission rate, remarkably strengthen the fast charging performance of the material, and further strengthen the stability and low-temperature performance of the material.

The embodiment of the invention provides a method for manufacturing foam glass by recovering glass fibers from waste fan blades. The method comprises the following steps: pyrolyzing the waste fan blades in an inert atmosphere; calcining the pyrolysis product of the waste fan blade in an oxygen-containing atmosphere to obtain regenerated glass fiber; carrying out grinding treatment on the obtained regenerated glass fiber; mixing the ground regenerated glass fiber powder with a foaming agent, a foam stabilizer and a binding agent, and performing compression molding to obtain a prefabricated blank; and sintering, foaming and annealing the prefabricated blank in sequence to obtain the foamed glass. The recycling of the fan blade reduces the waste of a landfill, realizes the recycling of the glass fiber, reduces the demand on raw materials, creates a new economic growth point by using the waste glass fiber for developing the foam glass market, and realizes the high-valued utilization of the recycled glass fiber.

The invention discloses a method for preparing a ternary positive electrode composite material. The method comprises the following steps: sintering a ternary positive electrode material precursor and a lithium source in an oxygen atmosphere to obtain a ternary positive electrode material; and introducing mixed gas of acid gas and oxygen into the ternary positive electrode material under the condition that the temperature does not exceed 900 DEG C to obtain the ternary positive electrode composite material. By adopting the technical scheme, on one hand, overgrowth or abnormal growth of crystal grains caused by overhigh temperature can be prevented; on the other hand, the residual alkali on the surface is effectively removed and is converted into inorganic salt with more stable thermodynamics, and the surface of the ternary positive electrode material is coated with the inorganic salt layer, so that the interface stability and the cycling stability of the material can be remarkably improved, and the resource utilization of wastes is also realized. The invention also discloses the ternary positive electrode composite material. The ternary positive electrode composite material is prepared by adopting the preparation method. The invention also discloses a lithium battery and a ternary positive electrode composite material.

The present invention belongs to the field of carbon-based composite materials, and particularly relates to a preparation method of a biomass-starch composite-based hard carbon material, which is obtained by pre-treating biomass under a low-oxygen atmosphere to obtain a heat-treated material, and then compounding the heat-treated material with starch and performing a roasting treatment; in the heat treatment stage, the oxygen partial pressure in the low-oxygen atmosphere is 1-15 v%, and the heat treatment temperature is 300-600 °C. The present invention also includes the material obtained by the above preparation method and its application in sodium batteries. The process of the present invention can solve the problem of starch thermal expansion, construct special physical and chemical structural characteristics, and can also improve the interfacial compatibility of carbons from different sources, thereby synergistically improving the sodium battery electrochemical performance of the material.

The invention provides a YBCO (Yttrium Barium Copper Oxide) film for a single-photon detector and a deposition method thereof, and the deposition method comprises the following steps: S1, fixing a substrate on a substrate table of pulse laser deposition equipment, vacuumizing, and heating the substrate table to a deposition temperature; s2, oxygen is introduced into the deposition cavity until the oxygen pressure ranges from 0.25 Torr to 0.35 Torr; s3, adopting a YBCO target material, and carrying out pre-sputtering in a baffle closing state; s4, a baffle is opened, sputtering is conducted on the YBCO target material, and a YBCO film precursor is obtained; s5, oxygen is introduced into the deposition cavity, and meanwhile, the annealing temperature is reduced for in-situ annealing treatment; and S6, cooling to room temperature to obtain the YBCO film. According to the method, the high-quality ultrathin YBCO film with the thickness as low as 14 nm is prepared by accurately controlling the deposition parameters and the annealing process of the oxygen atmosphere, the prepared YBCO film still keeps excellent superconducting performance under the ultrathin condition, and the refrigeration cost is greatly reduced.

The invention belongs to the technical field of preparation of soft magnetic composite materials, and particularly relates to an insulation coating method and application of a soft magnetic powder material. The insulating coating method comprises the following steps: (1) uniformly mixing low-melting-point metal or alloy powder with silica sol, a silane coupling agent and a thermocuring resin glue solution to obtain coating slurry; and (2) uniformly mixing soft magnetic powder with the coating slurry obtained in the step (1), firstly performing hot-pressing curing molding at the temperature of 60-100 DEG C under a vacuum condition, and then performing hot-pressing sintering treatment at the temperature higher than the melting point temperature of low-melting-point metal or alloy powder and under an oxygen-containing atmosphere condition to obtain the insulated and coated soft magnetic powder material. According to the insulating coating method, the advantages of an organic material insulating coating method and an inorganic material insulating coating method are combined, the defects of the organic material insulating coating method and the inorganic material insulating coating method are overcome, and the stability and the insulating coating effect of the insulating coating layer are remarkably improved.

The invention discloses a metal oxide precursor and a preparation method and application thereof. The precursor comprises a nickel element, a manganese element and an element M, and the element M comprises one or more of cobalt and aluminum. The preparation method comprises the steps that a mixed metal salt solution with the total metal ion concentration being 2-5 mol / L is prepared; spraying the mixed metal salt solution into a high-temperature pyrolyzing furnace in an aerial fog form, and carrying out a spray pyrolysis reaction; roasting the spray pyrolysis product for 1-4 hours in an oxygen-containing atmosphere, wherein the roasting temperature is 500-700 DEG C; dispersing the roasted product in an acidic aqueous solution, carrying out hydrothermal reaction at 150-250 DEG C for 1-6 hours, and carrying out filter pressing and washing until the conductivity of filtrate is less than 50 [mu] S / cm; and drying the washed product, and carrying out air jet pulverization to obtain the metal oxide precursor. During application, the metal oxide precursor and a lithium source are mixed and sintered to prepare the ternary positive electrode material. Impurities are removed through low-temperature roasting-acidic hydrothermal combination, the structure is optimized, and the performance of the positive electrode is improved.

To provide a method for evaluating the degree of oxidation of an oxidized polymer material.SOLUTION: When a standard piece made of a non-oxidized polymer material is measured by a chemiluminescence method while being heated in an oxygen-containing atmosphere to obtain a first integrated emission amount A, and a specimen made of the oxidized polymer material is measured by the chemiluminescence method while being heated in an oxygen-containing atmosphere to obtain a second integrated emission amount B, the degree of oxidation of the specimen is evaluated on the basis of an emission change rate R=(A-B) / A.SELECTED DRAWING: None

The utility model provides refrigeration equipment. The oxygen adjusting device comprises an oxygen adjusting storage container and an electrolysis oxygen adjusting module, the oxygen adjusting module is arranged in the oxygen adjusting container so that the oxygen-rich atmosphere or the oxygen-poor atmosphere can be supplied to the oxygen adjusting container, the oxygen adjusting container comprises a first oxygen adjusting container body and a second oxygen adjusting container body, the first oxygen adjusting container body is arranged in the second oxygen adjusting container body, and the electrolysis oxygen adjusting module is arranged in the second oxygen adjusting container body. Or the second oxygen adjusting container is arranged in the first oxygen adjusting container. By means of the arrangement, the concentration of oxygen in the oxygen adjusting container can be adjusted, and meanwhile the equipment structure is more compact.

The invention discloses a non-noble metal ORR catalyst and a preparation method thereof, and belongs to the technical field of electro-catalysis. The method comprises the following steps: (1) adding 5, 10, 15, 20-tetra (4-cyanophenyl) porphyrin and nickel salt into an organic solvent, and synthesizing a supramolecular crystal precursor UPC-S7 through solvothermal reaction; (2) carbonizing the supramolecular crystal precursor UPC-S7 in an inert atmosphere to obtain a Ni-coated NC material; (3) oxidizing the Ni-coated NC material in an oxygen-containing atmosphere to obtain a Ni / NiO-coated NC material; and (4) sequentially soaking and etching the Ni / NiO-coated NC material by using a nitric acid solution and an ammonia water solution, and then washing and drying to obtain the non-noble metal ORR catalyst. The prepared catalyst does not contain precious metal such as platinum, the raw material cost is remarkably reduced on the basis of ensuring the ORR activity and stability of the catalyst, and a new scheme is provided for solving the cost bottleneck of a fuel cell.

The invention belongs to the technical field of sodium ion battery negative electrode materials, and discloses an asphalt-based hard carbon material for a sodium ion battery and a preparation method of the asphalt-based hard carbon material. The 3, 4, 9, 10-perylenetetracarboxylic dianhydride is adopted as the cross-linking agent, the doping amount of the 3, 4, 9, 10-perylenetetracarboxylic dianhydride is only 10-30% of the mass of the asphalt, and the reversible sodium storage capacity of the asphalt can be remarkably improved under the condition limited by the invention. In an oxygen atmosphere, an anhydride group of 3, 4, 9, 10-perylenetetracarboxylic dianhydride and an oxygen-containing functional group in asphalt are subjected to a cross-linking reaction, and a formed cross-linking structure effectively inhibits melting rearrangement in an asphalt carbonization process, so that the electrochemical performance of the sodium-ion battery hard carbon negative electrode material is remarkably improved. According to the prepared asphalt-based hard carbon negative electrode material, 1 mol / L NaPF6-EC / DEC is used as an electrolyte, and under the current density of 20 mA / g, the initial coulombic efficiency reaches 75.64%, and the reversible capacity is 319.76 mAh / g; and under the current density of 200mA / g, the reversible capacity can still reach 189.14 mAh / g.

The invention provides a method for co-processing multi-source copper-based waste through copper concentrate, and relates to the field of metal smelting. The copper concentrate and the copper-based waste are subjected to first mixing, and a mixture is obtained; under the oxygen-containing atmosphere, the mixture is smelted, and matte and smelting slag are obtained; the matte and the silicon-based slag former are subjected to first blowing to obtain first blowing slag; carrying out second mixing on the first converting slag and a reducing agent, and carrying out second converting to obtain crude copper; the copper concentrates comprise copper sulfide concentrates and copper oxide concentrates. Copper concentrate matte smelting and copper-based waste pyrogenic smelting are combined together, the problems that the copper-based waste smelting scale is small, and furnace burning is caused by overburning are solved, and the problem that a slag former is additionally added in copper concentrate matte smelting is solved. Through collaborative smelting, valuable metals such as copper, gold and silver enter matte, iron, aluminum and silicon in the copper-based waste enter smelting slag, and a silicon-based slag former and a reducing agent are added when the matte is blown, so that the slagging function is realized, and the valuable metals in the waste are recovered.

The invention relates to the technical field of sodium ion battery negative electrode materials, in particular to a method for preparing hard carbon from medium-temperature coal tar-based pitch, which comprises the following steps: (S1) hydrogenating the medium-temperature coal tar-based pitch and a hydrogen donor solvent at high temperature and high pressure to obtain hydrogenated pitch; (S2) mixing the hydrogenated asphalt with a Lewis acid catalyst, and oxidizing in an oxygen-containing atmosphere to obtain first oxidized asphalt; (S3) uniformly mixing the first oxidized asphalt and a modifier, and carrying out secondary oxidation crosslinking to obtain second oxidized asphalt; and (S4) uniformly mixing the second oxidized asphalt and a pore-forming agent, and carrying out heat treatment in an inert atmosphere to obtain the product hard carbon material. The hard carbon material prepared by the method disclosed by the invention is benefited from a specific preparation process, shows relatively high specific capacity and first coulombic efficiency, and also has excellent rate capability. The preparation method is simple, low in cost and easy for large-scale production, and lays a foundation for large-scale production of the sodium-ion battery negative electrode material.

The invention provides high-purity superfine titanium diboride and a preparation method thereof, and relates to the field of titanium diboride preparation. The method comprises the following steps: mixing boron oxide, titanium hydride, a carbon source, nano rare earth oxide and an organic solvent, and drying to obtain a mixture; in a vacuum environment, performing first roasting on the mixture to obtain a first roasted material; and in an oxygen-containing atmosphere, carrying out second roasting on the first roasting material to obtain the high-purity superfine titanium diboride. In the first roasting process, boron oxide, titanium hydride and a carbon source are completely melted and fully contacted, then further, the carbon source forms a carbon skeleton, the contact area between the melted boron oxide and titanium hydride and the carbon skeleton is further enlarged, liquid-liquid mixing and the increase of the contact area can reduce the reaction kinetic conditions, the reaction temperature is greatly reduced, and the reaction time is greatly shortened. The particle size of the generated titanium diboride is reduced, and the molten boron oxide and titanium hydride react on the porous carbon skeleton in a liquid-liquid form to generate the high-purity superfine titanium diboride.

The invention discloses a CO2 adsorption material and a preparation method thereof.The method comprises the steps that 1, a coal-based raw material and an activating agent are mixed and ground to be uniform, and a mixture is obtained; 2) pre-oxidizing the mixture in an oxygen-containing atmosphere to obtain a pre-oxidized sample; 3) carbonizing and activating the pre-oxidized sample in a protective atmosphere, and then performing secondary activation in a CO2 atmosphere to obtain an activated sample; 4) washing the activated sample in an acid solution, washing in an aqueous solution, and drying to obtain an acid-washed sample; and 5) carrying out hot alkali treatment on the acid-washed sample in a high-temperature alkali solution, washing the sample subjected to hot alkali treatment with water, and drying to obtain the adsorption material. The adsorption material prepared by the method has the advantages of large micropore specific surface area, high CO2 adsorption capacity, high CO2 / N2 selectivity and the like, and the preparation process is simple, low in cost and very suitable for large-scale production and application.

The invention belongs to the technical field of third-generation semiconductor material defect control. According to the method for eliminating the silicon carbide small stacking fault based on high-temperature oxidation, a silicon carbide substrate is scanned and represented in a photoluminescence mode, and the target small stacking fault is accurately recognized and positioned; cleaning the substrate to remove surface impurities, performing high-temperature oxidation treatment in a dry oxygen atmosphere, and growing an oxide layer under control; constructing a composite interface stress field at an interface by utilizing thermal expansion coefficient mismatch and reaction molar volume expansion between the oxide layer and the substrate, and driving target stacking fault atom arrangement to generate directional reconstruction, so that the target stacking fault atom arrangement is converted into a matrix standard sequence; and finally, nitric oxide auxiliary annealing is carried out, and the reconstructed lattice configuration is solidified by utilizing a nitrogen passivation effect. The method is simple in process and high in compatibility, small stacking fault can be efficiently and stably eliminated, the silicon carbide substrate crystal quality is remarkably improved, and a guarantee is provided for preparation of a high-reliability power device.

The invention discloses an internal gettering process of a heavily boron-doped czochralski silicon epitaxial wafer, which comprises the following steps: 1) carrying out high-temperature pretreatment on a heavily boron-doped czochralski silicon wafer in an inert atmosphere, including high-temperature rapid heat treatment and high-temperature common heat treatment in sequence; 2) polishing the silicon wafer to eliminate a surface damage layer; and 3) depositing a lightly doped epitaxial layer or an intrinsic epitaxial layer to prepare the epitaxial wafer. After the epitaxial wafer is subjected to device manufacturing thermal process simulation in an oxygen atmosphere, gt can be formed on the near surface of the substrate; an inner gettering area with the BMD density larger than or equal to 5 * 10 < 9 > cm <-3 > is formed in the substrate body; the clean area guarantees the crystal quality of the epitaxial layer and prevents defects from extending to the active area; the inner gettering region enhances the inner gettering capability of the device on metal impurities, and reduces leakage current. The substrate of the epitaxial wafer formed by the method can be taken from any position of the self-weight boron-doped czochralski silicon single crystal ingot, so that the process is unified, the process integration complexity is reduced, and the waste of the crystal ingot is reduced.

The invention provides a volume photocuring three-dimensional printing method and device based on oxygen permeation interface dynamic oxygen inhibition control, and relates to the technical field of photocuring additive manufacturing. The volume photocuring three-dimensional printing method comprises the following steps that a resin cavity is prepared, the closed container is formed by compounding an oxygen permeable membrane and a transparent rigid material; establishing an oxygen inhibition layer: maintaining air or oxygen-containing atmosphere outside the closed container, so that oxygen continuously permeates into a resin boundary area through the oxygen permeation membrane to form the stable oxygen inhibition layer; volume light field projection: projecting a projection image generated by a computed tomography algorithm into the resin volume by adopting a calculation axial photoetching type multi-angle projection mode to realize multi-angle rotary projection exposure; edge curing is delayed through the boundary oxygen inhibition layer, the problem that the boundary light dosage of traditional volume printing is not uniform is solved, the final forming volume is enlarged by 1.5-3 times compared with the prior art, and the size bottleneck of volume light curing printing is effectively solved.

The invention belongs to the technical field of battery materials, and particularly relates to an asphalt-based hard carbon precursor, a hard carbon material and a preparation method and application of the asphalt-based hard carbon precursor and the hard carbon material. According to the method, protonic acid or lewis acid of a specific type and dosage is used as a catalyst to be mixed with the asphalt powder, and the reaction is carried out in an oxygen-containing atmosphere at a proper temperature, so that the synergistic promotion of oxidation and cross-linking is realized, the cross-linking activation energy of oxygen-containing functional groups is remarkably reduced, oxygen-containing active sites generated by asphalt oxidation are quickly and fully utilized, and the service life of the asphalt is prolonged. Therefore, the precursor with high oxygen content, stable cross-linked structure and good thermal stability is obtained. After the precursor is carbonized, the pitch-based hard carbon material with excellent electrochemical performance can be prepared, and the pitch-based hard carbon material is suitable for being used as a battery negative electrode material.

The invention discloses a boron diffusion method, a preparation method of a solar cell and the solar cell. The boron diffusion method comprises the following steps: preparing an oxide layer on the surface of one side of a silicon substrate; boron source pre-deposition is carried out on the oxide layer; propelling the pre-deposited boron source, including performing a first propelling process in an oxygen-free atmosphere, and performing a second propelling process, a third propelling process and a fourth propelling process in an oxygen atmosphere; and cooling the pushed silicon substrate. According to the boron diffusion method, the preparation method of the solar cell and the solar cell, the inter-sheet and in-sheet uniformity of the square resistance on the surface of the cell can be improved, the contact loss of a metal semiconductor is reduced, the carrier recombination is reduced, and the cell efficiency is improved.

The invention discloses a doped modified ternary positive electrode material, a preparation method thereof and a battery, and belongs to the technical field of batteries and ternary materials. The preparation method comprises the following steps: respectively weighing Ni0. 8Co0. 1Mn0. 1 (OH) 2, lithium hydroxide and a doping agent according to a molar ratio, mixing and grinding to form a mixture; and calcining the mixture in sections in an oxygen atmosphere, grinding and sieving to obtain the doped and modified ternary positive electrode material. The high-nickel ternary material is doped with a proper amount of Ti and V, and the Ti and V have a synergistic effect, so that the stability of the material structure is improved, the cation mixing degree is reduced, the reversible degree of the material and the reaction kinetics are improved, and the electrochemical performance of the material is improved.