378 results about "Carbon nanofiber" patented technology

The invention discloses a method for enriching light metal ions in a pore channel based on carbon nanofiber / carbon fiber nano confinement, and belongs to the technical field of sample pretreatment, and the method comprises the following steps: S1, preparing a carbon nanofiber / carbon fiber confinement material; and S2, putting the carbon nanofiber / carbon fiber confinement material obtained in S1 into a light metal ion solution, and stirring. According to the method for enriching the light metal ions in the pore channel based on the carbon nanofiber / carbon fiber nano confinement, the carbon nanofiber / carbon fiber is used as a confinement fluid carrier, ultrapure water, methanol or n-hexane is used as an extracting agent, a chelating agent does not need to be introduced, the method is green and environmentally friendly, the mass transfer rate is increased, and the method is suitable for large-scale industrial production. Therefore, high enrichment of light metal ions in water is realized.

The application belongs to the technical field of batteries, and particularly relates to a silicon-carbon negative electrode material and a preparation method and application thereof. The method comprises the following steps: preparing a porous carbon fiber membrane loaded with a metal catalyst; preparing a dispersion solution of a nano-silicon-based material, and distributing the nano-silicon-based material into the porous carbon fiber membrane to obtain a composite porous carbon fiber membrane; and performing thermal chemical vapor deposition on the composite porous carbon fiber membrane in an inert atmosphere containing a carbon source, growing carbon nanofibers and vertical graphene on the surface of the composite porous carbon fiber membrane, and obtaining a silicon-carbon negative electrode material. Through a synthesis route of thermal chemical vapor deposition (T-CVD), the synthesis process is optimized, and a multi-level three-dimensional network structure of carbon nanofibers and vertical graphene is constructed to enhance the electrical conductivity of the silicon-carbon negative electrode material, accelerate carrier transmission, improve the interface contact performance between the silicon-based material and the carbon material, improve the loading capacity of the nano-silicon-based material, inhibit the volume expansion of the nano-silicon-based material, and improve the structure and cycle stability of the nano-silicon-based material.

This invention relates to a method for synthesizing iron-cobalt alloy-doped carbon nanofibers for electrocatalysis using zinc oxide etching, belonging to the technical field of electrode materials and catalysts. The preparation method includes the following steps: 1) mixing DMF (dimethylformamide), PMDA (pyromellitic dianhydride), and ODA (4,4-diaminodiphenyl ether) in a certain proportion to prepare a PAA (polyamic acid) spinning solution; 2) preparing PAA nanofibers from the PAA spinning solution using an electrostatic melt-blowing device; 3) imidizing the PAA nanofibers using a programmed temperature rise method to obtain PI nanofibers; 4) impregnating the PI nanofibers in a salt solution; 5) carbonizing the impregnated PI nanofibers with a large number of metal ions on their surface in an inert atmosphere using a certain temperature rise program to obtain iron-cobalt alloy-doped carbon nanofibers. The iron-cobalt alloy-doped carbon nanofibers prepared by this method exhibit excellent performance as an ORR / OER bifunctional electrocatalyst and have wide applications.

The present invention discloses a triaxially spun superelastic and high-temperature resistant composite carbon nanofiber aerogel and a preparation method thereof. The aerogel is formed by interweaving curly fibers with a core layer of carbon and a shell layer of oxide ceramic. The present invention utilizes electrostatic spinning technology to prepare composite carbon nanofiber aerogels. First, an inner layer polyacrylonitrile solution is prepared, and the water / alcohol ratio is adjusted to prepare a middle layer ceramic sol with controllable water content, thereby obtaining a spinning solution with compatibility in the initial spinning stage. The temperature and humidity of the airflow of the outer nozzle are then regulated, and the water content of the ceramic sol is further adjusted during the spinning process, so that the spinning solution becomes incompatible. The spinning solution jet is fast and solidified in advance, thereby obtaining a curly interwoven structure nanofiber aerogel precursor. Finally, the final product is obtained by changing the atmosphere and performing rapid and continuous heat treatment. The present invention solves the problems of insufficient mechanical properties and easy oxidation of carbon nanofiber aerogels. The preparation method is simple and easy to implement, and the process is continuous, and can be carried out on existing electrostatic spinning production equipment.

The invention provides a flexible carbon nanofiber membrane as well as a preparation method and application thereof. The flexible carbon nanofiber membrane comprises a carbon nanofiber matrix and a modified material loaded in the carbon nanofiber matrix, the carbon nanofiber matrix comprises polyacrylonitrile, and the modified material comprises at least one of fluorine and zirconium oxide. The fluorine and / or zirconium oxide modified material is introduced, so that the performance is remarkably improved on the basis of a carbon nanofiber matrix, and the key defects of the existing carbon nanofiber membrane are effectively overcome. The invention also provides a preparation method and application of the flexible carbon nanofiber membrane.

The invention discloses a cellulose-based cationized carbon nanofiber / cyclodextrin composite demulsifier. The cellulose-based cationized carbon nanofiber / cyclodextrin composite demulsifier is obtained by sequentially carrying out cyclodextrin modification and cationized modification on cellulose-based carbon nanofibers. The preparation method comprises the following steps: firstly, taking biomass cellulose as a raw material, and sequentially carrying out chemical grafting modification, high-pressure homogenization treatment and hydrothermal reaction to prepare cellulose-based carbon nanofibers; then promoting the reaction between the cellulose-based carbon nanofibers and the natural cyclic oligosaccharide cyclodextrin under an ultrasonic condition, and improving the wettability and interfacial activity of the cellulose-based carbon nanofibers; finally, cyclodextrin is modified by utilizing a cationization reagent, so that the surface of cyclodextrin carries a large amount of positive charges, the interfacial activity of the carbon nanofibers is further enhanced, softening of an interfacial film is promoted, the stability of oil drops is reduced, and the demulsification efficiency is effectively improved. The composite demulsifier has the advantages of being small in dosage, low in demulsification temperature, high in demulsification efficiency, easy to degrade and the like, and the related preparation method is simple, environmentally friendly and suitable for application and popularization.

The invention provides a preparation method of a graphene carbon nanofiber film for oil-water separation, and relates to the field of oil-water separation membranes, and the preparation method comprises the following steps: mixing polyacrylonitrile powder and an N, N-dimethylformamide solution to obtain an electrostatic spinning solution; spinning through an electrostatic spinning machine to obtain a polyacrylonitrile fiber membrane; coating the polyacrylonitrile fiber film with the prefabricated graphene oxide dispersion liquid to obtain a graphene oxide / polyacrylonitrile composite film; carrying out pre-oxidation, activation and carbonization treatment on the composite film to obtain a graphene carbon nanofiber film; according to the method, the waste isostatic pressing graphite which is low in price and easy to obtain is adopted as the raw material, the ammonia activation means is combined, improvement is carried out on the basis of a Hummers method, graphene oxide is prepared, resource recycling is achieved, the isostatic pressing graphite waste generated in the production process is recycled and processed into a product with a high additional value, and therefore the purposes of reducing the production cost and saving resources are achieved.

The invention discloses an iron-nickel diatomic fiber catalyst with a precise and adjustable local structure and a preparation method and application thereof.The method is based on an organic small molecule coordination strategy and comprises the steps that ferric nitrate, nickel nitrate and dicyandiamide are dissolved in DMF according to a certain molar ratio, and a solution A is obtained; dispersing ZIF-8 nanoparticles in DMF (Dimethyl Formamide), and adding polyacrylonitrile to obtain a solution B; the solution A and the solution B are mixed to obtain a spinning solution, and a nanofiber membrane is obtained through electrostatic spinning; and carrying out pre-oxidation and high-temperature carbonization treatment on the nanofiber membrane to obtain the carbon nanofiber catalyst loaded with iron-nickel bimetallic atoms (metal diatoms, heterojunctions and alloys in which the metal diatoms and clusters coexist). The problem that the metal active site local structure of a metal diatom catalyst is difficult to accurately regulate and control is solved, and the prepared metal diatom heterojunction shows excellent ORR and OER bifunctional catalytic performance and cycling stability as a zinc-air battery positive electrode catalyst.

The invention discloses a solid-state battery negative electrode material and a preparation method and application thereof, and relates to the technical field of solid-state batteries. The preparation method comprises the following steps: uniformly mixing silicon nanowires, silicon nanoparticles, a carbon nanofiber precursor material and a solvent, preparing a negative electrode material precursor by adopting electrostatic spinning, and carrying out pre-oxidation treatment and carbonization treatment to prepare the solid-state battery negative electrode material, wherein the mass ratio of the silicon nanowires to the silicon nanoparticles is 1: (0.1-4). According to the invention, the silicon nanowires and the silicon nanoparticles are cooperated, and the carbon nanofibers are used as a carrier to form a three-dimensional network structure, so that the diffusion path, anisotropic stress distribution and crushing resistance of Li can be shortened, the cycle performance is improved, and the carbon nanofibers not only improve the mechanical stability of Si in the cycle process, but also provide good conductivity for the electrode. The problems of volume change and low conductivity of the silicon negative electrode material in the use process are effectively solved, and the interface stability of the silicon negative electrode material and a solid electrolyte material is enhanced.

The application provides a preparation method of integrated double-channel PCNFs / ZIF8-SA composite aerogel, a product and application thereof, and steps are as follows: step 1, sodium alginate (SA) and ZIF-8 are added into PCNFs suspension, and SA is fully dissolved by stirring until a uniform mixed solution is formed; the PCNFs are PAN / ZIF-8 / lignin / NaCl carbon nanofibers after hydrophilic modification; step 2, the mixed solution is poured into a mold, and directional freezing is carried out in a freeze dryer to obtain a composite aerogel columnar structure with a directional channel structure; step 3, the upper layer of the composite aerogel columnar structure is subjected to hydrophobic modification to form a hydrophobic layer with a certain thickness, and the lower layer is a hydrophilic layer, and the hydrophobic layer and the hydrophilic layer are integrated. The aerogel has a double-channel integrated special structure of fresh water channel and salt extraction channel, can extract accumulated salt from the side channel while realizing efficient solar seawater desalination, avoids the evaporation channel from being blocked, and greatly improves the evaporation efficiency and the stability of the composite aerogel.

The present invention belongs to the technical field of microwave-absorbing materials, and specifically relates to a method for preparing a cobalt / attapulgite / carbon nanocomposite fiber with microwave-absorbing properties. The preparation method comprises the following steps: mixing a magnetic metal salt, a polymer, a solvent, and nano-attapulgite in a specific proportion, reacting under heating conditions and at room temperature to obtain a mixed spinning solution; electrospinning the mixed spinning solution to obtain composite nanofibers; and carbonizing the obtained composite nanofibers to obtain a cobalt / attapulgite / carbon nanocomposite fiber with microwave-absorbing properties. The present invention has the beneficial effect that, due to the adoption of the above-mentioned technical solution, the carbon nanocomposite fiber of the present invention combines excellent properties such as light weight, strong absorption, a wide effective absorption bandwidth, and a low filling ratio. The carbon nanofibers have excellent dielectric properties, electrical conductivity, thermal stability, and low density. Carbon nanofibers are expected to be used to produce ideal microwave-absorbing materials.

The invention discloses a carbon nanofiber and carbonaceous honeycomb framework composite conductive agent material and a preparation method thereof, and belongs to the field of carbon materials. The method comprises the following steps: blending ferric nitrate and nickel nitrate with citric acid according to a molar ratio of 3: 1 to prepare an impregnation precursor solution; dipping an organic colloidal crystal template and drying to obtain a catalyst precursor; in a double-temperature-zone tubular furnace, a carbon source and a catalyst precursor are synchronously heated in a specific atmosphere, and the composite material with a fishbone-shaped structure is obtained through one-step roasting. The material is a composite system of carbon nanofibers and a carbonaceous honeycomb structure, the electronic conductivity reaches 40-140 S / cm, the structure and thermal stability are good, and the rate capability and cycle life of an electrochemical energy storage system such as a lithium ion battery can be remarkably improved and prolonged as a conductive agent. The method is simple in process and mild in condition, and has a good application prospect.

The invention relates to the technical field of environmental and biological analysis and detection, in particular to a method for extracting perfluorinated / polyfluorinated compounds based on confinement fluid. The method comprises the following steps: providing a multi-dimensional reticular nanopore material; growing mutually staggered carbon nanofibers on the surface of a substrate through a chemical vapor deposition method; loading a confinement fluid in a pore channel of the multi-dimensional reticular nano-pore channel material; contacting the material with a to-be-detected sample, and extracting; desorbing the extracted material by using a desorption solvent to obtain a desorption solution; and detecting the perfluorinated / polyfluorinated compounds in the desorption solution. A multi-dimensional net-shaped nano pore channel formed by mutual staggering of the carbon nanofibers provides a stable multi-dimensional micro-nano confinement space for confinement fluid. According to the structure, mass transfer and distribution of a target analyte from a complex matrix to a confinement fluid are greatly promoted, so that efficient enrichment of various perfluoro / polyfluoro compounds is realized, and the recovery rate and the detection sensitivity of the method are improved.

The invention relates to a carbon nano reinforced thermoplastic polyurethane composite material as well as a preparation method and application thereof. The composite material is prepared from the following components in parts by mass: 5 to 20 parts of diisocyanate, 10 to 30 parts of oligomer dihydric alcohol, 1 to 10 parts of bifunctional chain extender and 1 to 20 parts of filler, the filler is prepared from the following components in parts by mass: 0.95 to 18 parts of inorganic filler and 0.05 to 2 parts of carbon-based nano filler; preparing a carbon-based nanofiller of flaky carbon nanofibers, tubular carbon nanofibers or fishbone-shaped carbon nanofibers from reaction gas by using a metal catalyst through a chemical vapor deposition method; the metal catalyst is selected from an iron-nickel catalyst or a nickel-copper catalyst, the reaction gas comprises a carbon source gas and a reducing gas, the carbon source gas is selected from carbon monoxide or ethylene, and the reducing gas adopts hydrogen. Compared with the prior art, the material has good mechanical properties and damping performance, especially has excellent normal-temperature damping performance and damping temperature range, and is suitable for 3D printing.

The invention relates to an activated carbon electrode material for a supercapacitor and a preparation process thereof, and belongs to the technical field of activated carbon electrode materials. The preparation process provided by the invention specifically comprises the following steps: mixing cane sugar, ammonium dihydrogen phosphate, deionized water and zinc gluconate, carrying out spray drying at 80 DEG C to obtain precursor powder with a loose structure, carbonizing, then carrying out pulse activation, water vapor reaming, cooling and post-treatment, mixing the obtained composite material with carbon nanofibers, a PTFE binder and absolute ethyl alcohol, and carrying out ball milling, so as to obtain the carbon nanofiber composite material. And coating the obtained slurry with an aluminum foil, drying, rolling, and carrying out hot press molding, thereby obtaining the product. According to the invention, cane sugar is used as a carbon source, zinc gluconate is introduced to assist in forming a honeycomb-shaped pore frame, and a honeycomb-shaped porous structure is formed along with further increase of carbonization temperature and multiple cyclic pulse activation and water vapor chambering processes, so that the ion transmission efficiency is improved, and the loss of a specific capacitance value under high current density is reduced; the capacitance performance of the material is improved.

The invention belongs to the technical field of coating preparation and provides a modified high-strength one-component polyurea coating and a preparation method thereof. First, PDA@electrospun carbon nanofibers are prepared by reacting a Tris-HCl buffer solution under alkaline conditions, and the functional properties and interfacial bonding strength of the fibers are enhanced by surface dopamine coating. Secondly, a metal coordination microgel is prepared by an emulsion polymerization method, and a high-strength, corrosion-resistant functional microgel structure is constructed through the synergistic effect of acrylamide monomer, metal salt and benzotriazole. Then, a matrix resin is prepared by reacting isocyanate with an amino-terminated polyether under a nitrogen atmosphere, and its storage stability and curing behavior are regulated by combining a latent amine and a composite blocking agent. Finally, the PDA@nanofibers, the metal coordination microgel and an auxiliary agent are uniformly dispersed in the matrix resin to prepare a modified high-strength one-component polyurea coating suitable for application in complex environments.

A sensing element may include a composition comprising 3D chemically connected carbon structures, for example formed of chemically connected nanomaterials, such as, Carbon Nanotubes, Carbon Nanofilaments, Carbon Nanofibers or Graphene Nanoplatelets The structures may be embedded in a polymer. Other particles such as metal oxides may also be incorporated in a polymer. The sensing element that may be applied on to a surface for sensing leakage, of a transportation and / or storage structure including hydrocarbon storage structures. Electrical signals from the sensing element are processed to check for indicators of leakage.

The invention provides a laser-electric coupling Taylor cone bionic electrospinning process method, a folded conductive metamaterial and application, the preparation method comprises the following steps: dissolving a carbon nanotube in N, N-dimethylformamide, stirring and carrying out ultrasonic treatment, then adding polymer powder, and continuously stirring to obtain a precursor solution; in the first stage, electrostatic spinning is carried out, meanwhile, a laser beam with the wavelength of 589-650 nm is focused on a rotating Taylor cone for electrostatic spinning, the treated spinning film is heated in air, heat preservation is carried out, then the temperature is reduced to the room temperature, and in the first stage, heating is carried out firstly, and then heat preservation is carried out; then raising the temperature in the second stage, keeping the temperature, and finally cooling to room temperature; in the coupled field spinning process, the synergistic effect of arrangement of the carbon nanotubes and the carbon nanofibers induced by photo-thermal response, local fluidity enhancement and an electric field jointly promotes axial dispersion and slidable in the fibers and formation of a self-adaptive network; and the folded conductive metamaterial capable of being folded for 10 million times is successfully prepared.

Disclosed is a PAN-PVA hybrid nanofiber-based porous carbon nanofiber electrode, which has a large surface area, low production cost, easy scalability, tunable structure, effective ion diffusion paths, high electrical conductivity, flexibility, free-standing structure, and improved specific capacitance values due to surface area. Also disclosed is the production method for use of the electrode in solid-state supercapacitors.

The application discloses a preparation method of a lithium battery negative electrode material Mo2C / NiO@GO carbon nanofiber, and comprises the following steps: S1, weighing nickel oxide, ammonium molybdate tetrahydrate and a solvent and performing ultrasonic treatment; S2, weighing a high-molecular surfactant, adding the high-molecular surfactant into a beaker and stirring at normal temperature to obtain a spinning solution; S3, adopting a needle tube to suck the spinning solution and performing electrostatic spinning to obtain a precursor, taking down the precursor after spinning is completed, and drying the precursor in an oven; S4, pre-sintering the dried precursor; S5, performing suction filtration on the pre-sintered precursor; and performing heat treatment on the suction filtration and drying precursor to obtain the required lithium ion battery negative electrode material. The preparation method of the application obtains the Mo2C / NiO@GO material with a three-dimensional network structure, improves the specific surface area and the conductivity of the negative electrode material, and the obtained battery has high specific capacity and good cycle stability, and has significant economic value.

The utility model provides an aerosol generating product, the aerosol generating product comprises a fuming part, a power supply part and a filtering part, the fuming part comprises a fuming substrate and a heating element which are in thermal contact with each other, and the heating element is used for heating the fuming substrate; the power supply part comprises a power supply electrically connected with the heating element; the filtering part is arranged at the downstream of the fuming part; and the heating element is made of carbon nanofibers. According to the aerosol generating product provided by the invention, the heating element is made of the carbon nanofibers, so that the heating rate can be effectively increased, and the reliability and user experience of the aerosol generating product can be improved.

The invention discloses a silicon-carbon composite negative electrode material and a preparation method thereof, the silicon-carbon composite negative electrode material comprises a core-shell active unit, a conductive network layer and a composite coating layer, the core-shell active unit is a structure formed by loading boron-doped silicon quantum dots in hollow carbon spheres; the composite material is prepared from the following components in percentage by mass: 11 to 18 weight percent of boron-doped silicon quantum dots, 24 to 36 weight percent of hollow carbon spheres, 31 to 42 weight percent of polyimide-derived nitrogen-doped carbon nanofibers, 3 to 8 weight percent of fluorophosphate-aluminum oxide composite coating layer and 2 to 5 weight percent of lithium titanate modified montmorillonite, the mass ratio of fluorophosphate to aluminum oxide in the fluorophosphate-aluminum oxide composite coating layer is 3: 1, the particle size of the boron-doped silicon quantum dots is 2-5nm, the doping amount of the boron element is 1-3at%, and the purity is not lower than 99.95%. The core-shell structure is used for buffering silicon expansion, the nitrogen-doped carbon fiber is used for constructing a high-efficiency conductive network, the composite coating layer is used for stabilizing an interface, and the inorganic dispersed phase is used for inhibiting agglomeration, so that the specific capacity, the cycling stability and the first charge-discharge efficiency of the lithium ion battery are remarkably improved.

The invention relates to the technical field of refractory materials for steelmaking, in particular to a long-life refined ladle brick and a preparation method thereof. The long-life refined ladle brick provided by the invention consists of a mixture and a binding agent, the mixture is prepared from the following raw materials in parts by weight: 55 to 84 parts of RH magnesium aluminate spinel brick reclaimed materials with the particle size of less than or equal to 8mm, 5 to 9 parts of fused magnesia with the particle size of less than or equal to 1mm, 10 to 15 parts of macrocrystalline fused magnesia fine powder and 6 to 15 parts of carbon nanofibers; the binding agent comprises the following raw materials in parts by weight: 1-3 parts of liquid phenolic resin, 1-6 parts of silica sol and 1-2 parts of liquid water glass. The long-life refined ladle brick provided by the invention has the advantages of good volume stability, strong thermal shock resistance, excellent oxidation resistance and slag erosion resistance and long comprehensive service life.

The invention discloses an oxygen-doped carbon nanofiber bifunctional electrocatalytic oxidation film and a preparation method and application thereof. The atomic ratio of nitrogen atoms to oxygen atoms in the oxygen-doped carbon nanofiber bifunctional electrocatalytic oxidation film is 11: (6-15). The catalytic performance of the electrocatalytic oxidation film can be improved by controlling the atomic ratio of nitrogen atoms to oxygen atoms in the oxygen-doped carbon nanofiber bifunctional electrocatalytic oxidation film, and then the catalytic efficiency of the electrocatalytic oxidation film is improved.

The invention discloses a carbon nanofiber tube laying device. The device comprises an equipment main body; the fiber pipe fixing mechanisms are arranged on the two side walls of the laying cylinder; the laying mechanism is arranged in the laying cylinder; and the conveying mechanism is arranged in the outer shell. Compared with the prior art, the device has the advantages that by arranging the fiber pipe fixing mechanism, the two ends of the fiber pipe can be fixed in the laying process, stability in the laying process is ensured, meanwhile, the fiber pipe fixing mechanism can adapt to different fiber pipe diameters, the effective protection and sealing effects are achieved, and the service life of the fiber pipe is prolonged. In addition, an ultrasonic atomization nozzle is adopted in the laying mechanism, the carbon fiber pipe is atomized and laid on the surface of the fiber pipe, and in cooperation with movement and rotation of an inner ring base, it is ensured that the carbon fiber pipe can be evenly laid on the surface of the fiber pipe, laying uniformity is ensured, and it is ensured that the toughening and reinforcing effect is achieved.

The present disclosure provides a washed sulfur impregnated 3D carbonized carbon nanofiber foam (SCCNF-f-AW) for lithium-sulfur battery and a method of preparation thereof. The washed sulfur impregnated 3D carbonized carbon nanofiber foam (SCCNF-f-AW) acts as an electrode, exhibiting high sulfur loading and stability; improving the energy storage capacity and life cycle of lithium-sulfur batteries.

This invention belongs to the field of microwave absorbing materials technology, specifically relating to a composite carbon nanofiber microwave absorbing material, its preparation method, and its applications. The composite carbon nanofiber microwave absorbing material is obtained by electrospinning and heat treatment using a polynuclear pentameric acid metal complex as a precursor and polyacrylonitrile as a carbon source. The polynuclear pentameric acid metal complex is any one of trinuclear iron pentameric acid, dinuclear cobalt pentameric acid, and dinuclear nickel pentameric acid. The excellent microwave absorption performance of the composite carbon nanofiber microwave absorbing material in this invention achieves uniform loading of the nanophase, increases the number of heterogeneous interfaces, and enhances dissipation processes such as interfacial polarization, providing a feasible path to solve the common problems of particle agglomeration and impedance mismatch in composite systems.

The invention relates to the technical field of hydrogen-resistant lining materials, and provides a hydrogen-resistant lining material for a high-strength and high-toughness hydrogen storage container and a preparation method of the hydrogen-resistant lining material, the hydrogen-resistant lining material comprises the following components: modified carbon nanofiber, anhydride modified ethylene copolymer and polyamide; the modified carbon nanofiber is of a core-shell structure, and the core-shell structure takes carbon nanofiber as a core and takes graphene oxide as a shell; the carbon nanofibers are grafted with amino groups; performing electrostatic winding on amino and graphene oxide; in the components, the carbon nanofibers are grafted with amino groups to realize cationization modification, so that the Zeta potential of the carbon nanofibers is changed from negative to positive, so that a graphene oxide sheet layer with negative electricity is tightly wound on the surface of the carbon nanofibers at a specific angle, and a core-shell structure in which the carbon nanofibers are tightly wrapped by the graphene oxide sheet layer is further formed; the graphene oxide shell layer effectively covers defects and microcracks on the surface of the carbon nanofiber, eliminates a short-circuit channel for hydrogen permeation, and improves the hydrogen resistance effect.

The invention belongs to the field of preparation of lithium ion battery negative electrode materials, and particularly relates to a multi-stage silicon-carbon composite material for a battery negative electrode and a preparation method of the multi-stage silicon-carbon composite material. The method comprises the following steps: firstly, weighing DMF, Si NPs and PAN, carrying out ball milling, and then carbonizing in an N2 atmosphere to obtain a Si-C primary structure of a target sample; then uniformly dispersing Si-coated C and PAN in a DMF (Dimethyl Formamide) solution to obtain an electrostatic spinning working solution, and then preparing a Si-coated C composite PAN nanofiber membrane Si-coated C / PAN under an optimal electrostatic spinning working condition; and finally, stabilizing the fiber structure of the Si-coated C / PAN in the air, and carbonizing in the N2 atmosphere to obtain the multistage silicon-carbon composite material Si-coated C / CNFs for the battery negative electrode prepared by electrostatic spinning. According to the invention, an amorphous carbon layer is compounded on the surface of Si NPs by a ball milling method, and a carbon nanofiber network is built in combination with electrostatic spinning, so that the Si NPs are subjected to double constraints of amorphous carbon and carbon nanofibers. And the prepared silicon-carbon composite negative electrode material shows excellent cycling stability and rate capability.

This invention belongs to the field of lithium-sulfur battery technology, providing a zirconium-based flexible carbon nanofiber membrane, its preparation method, a lithium-sulfur battery cathode, and a lithium-sulfur battery. The preparation method involves mixing a zirconium source, a polymer, and an organic solvent to form a spinning solution; the spinning solution is electrospun to obtain a fiber membrane; the fiber membrane is then carbonized to obtain the zirconium-based flexible carbon nanofiber membrane. This invention yields a zirconium-based flexible carbon nanofiber membrane with high conductivity, a well-structured microstructure, and active sites for zirconium-based compound nanoparticles. The zirconium-based flexible carbon nanofiber membrane with its well-structured microstructure and active sites for zirconium-based compound nanoparticles exhibits excellent chemical / physical adsorption characteristics for polysulfides. Simultaneously, the zirconium-based compound nanoparticles possess excellent electrocatalytic properties, accelerating efficient conversion between polysulfides, achieving efficient electron transfer and ion diffusion, and realizing high sulfur utilization. This results in excellent areal capacity electrochemical performance. When used as a cathode in lithium-sulfur batteries, it enables the lithium-sulfur battery to exhibit outstanding rate performance and cycle stability, promoting the development of lithium-sulfur batteries towards low-altitude economic applications. Furthermore, the zirconium-based flexible carbon nanofiber membrane, when combined with a high-sulfur-loaded sulfur cathode (greater than 6 mg / cm³), further enhances the effectiveness of the process. 2 Together, they constructed a novel "sandwich" sulfur cathode, resulting in a high-capacity lithium-sulfur battery.