134results about How to "High specific capacity" patented technology

The invention relates to the field of solid-state batteries, in particular to a halide electrolyte, a preparation method and a solid-state battery. The halide electrolyte comprises a tin element, and the chemical formula of the halide electrolyte is Li2Zr < 1-x > Sn < x > Cl < 6-4x > O < 2x >, and x is less than or equal to 0.3. Through tin-oxygen co-doping, force is exerted at the same time from the two aspects of crystal structure (bulk phase) and interface chemistry, the key problems of ionic conductivity, electrochemical stability, interface compatibility and the like are cooperatively solved, the cost and the process are perfectly considered, and an all-solid-state battery electrolyte solution with a great commercialization prospect is provided.

The application discloses a synthesis method of a large single-crystal sodium-ion battery layered oxide positive electrode material, and comprises the following steps: (1) weighing metal oxides containing transition metal elements, transferring to a device with mixing functions, uniformly mixing, and obtaining a metal oxide mixture; (2) adding acid to the metal oxide mixture, fully mixing, and completing an acid treatment process; (3) adding alkali to the mixture after acid treatment, fully mixing; (4) transferring the mixture obtained in the step (3) to a calcining furnace, high-temperature calcining, and obtaining a layered oxide. The acid treatment process is introduced, the surface of the metal oxide forms a defect structure under the action of the acid, and the defect structure is more beneficial to the formation of strong interaction between each component of the metal oxide and between the metal oxide and sodium-containing alkali, so that a larger single-crystal layered oxide structure is finally formed, and the specific capacity, rate performance and cycle performance are excellent.

This invention belongs to the technical field of lithium-ion battery cathode materials, specifically relating to a sulfonic acid-based organic polymer, a sulfonic acid-based organic polymer / carbon nanotube composite material, its preparation method, and its application. The sulfonic acid-based organic polymer is prepared by a dehydration condensation reaction of 2,5-diaminobenzenesulfonic acid and hexaazabenzophenanthrene hexacarboxylic acid trianal. When used as a lithium-ion battery cathode material, it exhibits high specific capacity and excellent cycle stability, overcoming the solubility problem of organic cathode materials in electrolytes. When the sulfonic acid-based organic polymer is combined with carbon nanotubes and applied to lithium-ion battery cathode materials, battery performance is significantly improved, and the capacity remains stable even after long-term cycling. The synthesis methods of the sulfonic acid-based organic polymer and the sulfonic acid-based organic polymer / carbon nanotube composite material of this invention are simple, have abundant raw material sources, and good reproducibility, making them suitable for industrial production and possessing broad application prospects in the field of lithium-ion batteries.

This invention belongs to the field of hard carbon technology, specifically relating to a bamboo-based and lignin-based hard carbon composite material, its preparation method, and its applications. The process involves pretreating raw materials to obtain pretreated material; pretreating the pretreated material with an acidic oxidant to obtain acidic oxidant pretreated material; pre-oxidizing the acidic oxidant pretreated material to obtain pre-oxidized material; pre-carbonizing the pre-oxidized material under a protective atmosphere to obtain pre-carbonized material; pulverizing the pre-carbonized material to obtain pulverized material; acid washing followed by water washing to obtain purified material; soaking the purified material in acid, filtering, and drying to obtain soaked material; mixing the soaked material with a modifier, and high-temperature coating and carbonizing under a protective atmosphere to obtain bamboo-based coated hard carbon or lignin-based coated hard carbon. Mixing the two types of hard carbon and carbon coating yields a bamboo-based and lignin-based hard carbon composite material, which is used in negative electrode sheets and batteries. When applied to batteries, the hard carbon composite material of this invention can improve battery energy density.

The invention relates to an O2-phase lithium cobalt oxide positive electrode material and a preparation method thereof, and belongs to the technical field of lithium ion batteries. The preparation method comprises the following steps: S1, uniformly mixing a doped metal source, a sodium source and a cobalt source, sintering, and cooling to obtain a P2-phase precursor; s2, uniformly mixing the P2-phase precursor, a lithium source A and the coating layer precursor, sintering, and cooling to obtain an intermediate A; s3, uniformly mixing the intermediate A and a lithium source B, sintering, and cooling to obtain an intermediate B; and S4, uniformly mixing the intermediate B and a lithium source C, sintering, cooling, washing and drying to obtain the O2-phase lithium cobalt oxide positive electrode material. The O2-phase lithium cobalt oxide positive electrode material with low residual sodium, high structural stability and excellent interface coating performance is prepared through a method of combining gradient ion exchange, gradient temperature control, gradient atmosphere regulation and control and synchronous in-situ coating.

The invention relates to the technical field of sodium-ion batteries, in particular to a sodium-ion battery positive electrode material and a preparation method thereof. The sodium ion battery positive electrode material is Ti and Cl doped Na4VMn (PO4) 3, and the molar ratio of Na to Ti in the sodium ion battery positive electrode material is 4: (0.05-0.1); the molar ratio of Na to Cl is 4: (0.05-0.1). According to the sodium-ion battery positive electrode material provided by the invention, a titanium element and chlorine element synergistic co-doping mode is adopted, so that the ginger-Taylor distortion caused by manganese ions in the charging and discharging process can be inhibited, the lattice stress can be reduced, and the stability of the material structure can be enhanced; meanwhile, the dissolution of manganese under a high-rate cycle condition can be inhibited, and the loss of active substances and the side reaction of electrolyte are reduced, so that the electrochemical stability and the structural integrity of the electrode material are improved, and the sodium ion battery containing the positive electrode material has relatively high specific capacity, excellent rate capability and cycle stability.

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

The application relates to a preparation method of a sulfonated asphalt carbon@BiOCl sodium ion battery negative electrode composite material. Bi(NO3)3.5H2O and A are dissolved in ethylene glycol, 3-aminopropyl methoxysilane is added into the ethylene glycol, and stirring is conducted to form a uniform suspension; A is SnCl4.5H2O, SnCl4 or SnCl2; sulfonated asphalt is added into the suspension, and magnetic stirring is conducted; then the suspension is moved into polytetrafluoroethylene and is placed into a high-pressure reaction kettle for constant temperature treatment at 160-200 DEG C for 10-24h; after the reaction kettle is cooled to room temperature, centrifugal separation is conducted, and drying is conducted; 4) the sample is subjected to constant temperature treatment at 600-1000 DEG C for 1-3h in a tubular furnace in an inert atmosphere, and the temperature is reduced to room temperature. Advantages are that the sodium ion battery negative electrode composite material with high performance is prepared through a simple one-step hydrothermal method, and the sodium ion battery negative electrode composite material has high specific capacity and excellent rate performance.

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.

The application provides an anode foil and a preparation method thereof. The preparation method comprises the following steps: providing an unformed foil, wherein the unformed foil comprises an aluminum foil base material and an aluminum powder sintering layer arranged on the surface of the aluminum foil base material; and sequentially performing the following processes on the unformed foil: water boiling, first-stage chemical conversion, second-stage chemical conversion, third-stage chemical conversion, power feeding treatment, fourth-stage chemical conversion, fifth-stage chemical conversion, first-stage heat treatment, first chemical conversion repair, first phosphoric acid treatment, second chemical conversion repair, second-stage heat treatment, third chemical conversion repair and second phosphoric acid treatment. The solutes of the electrolyte of the first-stage chemical conversion, the second-stage chemical conversion and the third-stage chemical conversion comprise citric acid, triammonium citrate, adipic acid, ammonium adipate, salicylic acid, hypophosphite, boric acid and ammonium salt, and the solvent is water. The solutes of the electrolyte of the fourth-stage chemical conversion and the fifth-stage chemical conversion comprise citric acid, triammonium citrate, sebacic acid, ammonium sebacate, salicylic acid, sodium hypophosphite, boric acid and ammonium salt, and the solvent is water. An anode foil prepared by the preparation method has a high specific capacity and a small hydration leakage current.

This invention discloses a low-temperature resistant, high-power aqueous organic-bromine battery, belonging to the field of electrochemical energy storage technology. The invention uses a low-freezing-point bromine-based salt solution with added bromine solid complexing agent as the electrolyte, and a pseudocapacitive organic material as the negative electrode, which possesses ionic universality and can bind metal ions in the solution during the reaction. The positive electrode uses a carbon material as a substrate, where a bromine redox reaction occurs. Simultaneously, the complexing agent can complex bromine in solid form onto the carbon surface, ensuring good stability at both room temperature and low temperatures. The aqueous organic-bromine battery of this invention exhibits high energy density and ultra-high power density at room temperature, maintains high energy density even at low temperatures, and is inexpensive, showing promising application prospects.

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.

The application discloses a positive electrode material and a preparation method and application thereof, and the preparation method comprises the following steps: mixing iron phosphate, a carbon source, a sodium source and water to prepare a slurry; the mixed iron phosphate contains phosphate and pyrophosphate or phosphate and dihydrogen phosphate; the carbon source contains citric acid; the prepared slurry is grinded to obtain a fine slurry; the fine slurry is sprayed and dried to obtain a solid precursor; and the solid precursor is sintered to obtain the positive electrode material. By controlling the reaction parameters, the mixed iron phosphate containing pyrophosphate or dihydrogen phosphate is synthesized, the amount of citric acid in the subsequent process is reduced, the pore generation rate is reduced, the material compaction density is improved, the method is simple and reliable, and the application prospect is good. The prepared positive electrode material has high specific capacity and high compaction density, and is suitable for preparing a positive electrode of a sodium ion battery.

The application discloses a composite pyrophosphate magnesium battery positive electrode material and a preparation method and application thereof. The positive electrode material comprises a magnesium ion positive electrode material pyrophosphate and a carbon layer coated on the magnesium ion positive electrode material pyrophosphate. The chemical formula of the positive electrode material is Mg a Na b M 2+x / 2 N y , wherein M is one or more of Fe, V, Ti, Cr, Ni, Cu, Mn, Co, Nb, N is one or more of P2O7 4‑ , PO4 3‑ , SO4 2‑ , BO3 3‑ , SiO4 4‑ , 0

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.

This invention relates to a high-efficiency, high-capacity silicon-carbon composite anode material, its preparation method, and its application. The silicon-carbon composite anode material comprises: a phosphorus-doped silicon-carbon material, and a composite coating layer covering the outer surface of the phosphorus-doped silicon-carbon material. A Si-P-C bond structure exists between the phosphorus-doped silicon-carbon material and the composite coating layer. The phosphorus-doped silicon-carbon material comprises: a porous carbon matrix, and nano-silicon particles and phosphorus elements deposited in the pores of the porous carbon matrix. The composite coating layer comprises: a carbon coating layer, and C-F bonds formed in situ within the carbon coating layer. Applying the silicon-carbon composite anode material provided in this invention to lithium-ion batteries can improve the first-cycle coulombic efficiency and cycle stability of lithium-ion batteries, and reduce the expansion rate.

The invention relates to the technical field of lithium ion battery positive electrode materials, in particular to an aluminum-yttrium-boric acid coated high-nickel positive electrode material and a preparation method and application thereof. The preparation method of the material comprises the following steps: synthesizing a doped and modified high-nickel ternary precursor from a mixed metal salt solution and a first aluminum source and / or a first yttrium source through a coprecipitation reaction; mixing the precursor with a lithium source, and performing first sintering treatment to obtain a base material; and mixing the base material with a solution containing boric acid, a second aluminum source and a second yttrium source, and carrying out solvent evaporation and second sintering treatment to obtain a final product. Through the synergistic effect of bulk phase doping and surface composite coating, generation of intragranular cracks and interface side reaction of the material in the circulation process are inhibited at the same time. The obtained positive electrode material successfully overcomes the technical problem that high capacity and long service life are difficult to consider at the same time, and the cycling stability is remarkably improved while the high specific capacity is kept.

The invention provides an aqueous cadmium ion-vanadium dioxide battery as well as a preparation method and application thereof, and relates to the field of ocean energy storage. The battery comprises a negative electrode, a positive electrode, a diaphragm and an aqueous electrolyte, the negative electrode is metal cadmium or cadmium-based alloy; the active material of the positive electrode is metastable monoclinic phase vanadium dioxide; the diaphragm is a glass fiber diaphragm; the aqueous electrolyte is an aqueous solution containing cadmium salt; the total concentration of the cadmium salt in the aqueous electrolyte is 1-4 mol / L. The aqueous vanadium dioxide-cadmium metal secondary battery disclosed by the invention has the advantages of safe aqueous electrolyte system, high rate capability, ultra-long cycle life and the like, and has remarkable advantages when being applied to ocean energy storage.

The invention discloses a preparation method of a metal-semimetal double-monatomic catalyst loaded on the basis of a carbon molecular sieve. The preparation method comprises the following steps: S1, carrying out activation pretreatment on a carbon molecular sieve carrier; s2, mixing the pretreated carbon molecular sieve powder with a copper salt and a selenium source, adding a solvent, stirring, and performing ultrasonic treatment to obtain precursor powder; and S3, putting the precursor powder obtained in the step S2 under inert atmosphere protection, and carrying out heat treatment. Through the electronic coupling and synergistic effect between copper and selenium atoms, the electronic structure of the catalyst can be precisely regulated and controlled, the efficiency of a reaction path is optimized, the interaction between copper and LiPSs is promoted, the catalytic performance of the catalyst is enhanced, in the adsorption and catalytic conversion process, the affinity of LiPSs and the catalyst is remarkably improved, the shuttle effect is inhibited, and the catalytic performance of the catalyst is improved. And the method has wide application prospect and important value in the research and practice of the lithium-sulfur battery.

The invention discloses a layered oxide positive electrode material of a sodium-ion battery and a preparation method of the layered oxide positive electrode material, and belongs to the technical field of batteries. The method comprises the following steps: preparing a NaNi < 0.33 > Mn < 0.33 > Fe < 0.33 > O2 precursor, mixing the precursor with a Na2S and P2S5 mixture under argon, carrying out heat treatment at 500 DEG C, and sintering with sodium hydroxide in an oxygen atmosphere at 800 DEG C to obtain the material. The core of the material is that a continuous super-ion conductor phase is formed on a grain boundary, a three-dimensional ion transmission network and a mechanical strengthening framework are constructed, the ion diffusion efficiency and the structural stability are remarkably improved, high-rate and long-cycle performance breakthrough is achieved, the process is controllable, and the industrialization potential is large.

The application discloses a low-temperature Prussian white sodium ion battery, which comprises a positive electrode, an electrolyte and a negative electrode, the positive electrode is selected from a Prussian white positive electrode material; the electrolyte comprises a sodium salt, an organic solvent and an electrolyte additive; the concentration of the sodium salt in the electrolyte is 0.4-0.7 mol / L; and the electrolyte additive comprises a fluorinated carbonate and a fluorinated acetate. The low-temperature Prussian white sodium ion battery disclosed by the application has high specific capacity and long cycle life at a low temperature of-20 DEG C.

A method for preparing coal tar pitch-based hard carbon anode material belongs to the field of anode materials. This method uses coal tar pitch as a raw material, leveraging its advantages of wide availability and high carbon content (rich in aromatic compounds). A precursor is obtained by adding a crosslinking agent and a modifier, followed by high-temperature sintering to obtain hard carbon. This invention improves the interlayer spacing of the material through the modifier, resulting in hard carbon with high specific capacity and initial coulombic efficiency, with an initial discharge specific capacity exceeding 300 mA hg. ‑1 .

The application provides a preparation method of a sodium-rich and low-water-content Prussian blue positive electrode material, which comprises the following steps: dissolving sodium ferrocyanide or a hydrate thereof and a complexing agent in deoxygenated water under an inert gas atmosphere and at a certain temperature to obtain a mixed solution A; dissolving a transition metal salt or a hydrate thereof, a sodium supplementing agent, a complexing agent and an auxiliary complexing agent in deoxygenated water under an inert gas atmosphere and at a certain temperature to obtain a mixed solution B; continuously stirring solution A and solution B by dropwise adding them into a container with a positive pressure inert gas atmosphere and at a certain temperature, continuing to stir for a period of time after the dropwise adding is completed, and then standing, centrifuging and vacuum drying to obtain the Prussian blue positive electrode material. The Prussian blue positive electrode material comprises a mixed phase structure of rhombic phases and cubic phases, has the characteristics of high sodium content and low water content. The battery assembled by using the positive electrode material obtained by the method has a theoretical specific capacity close to the theoretical specific capacity under a small current density and still has a high specific capacity under a large current density.

The application discloses a biomass gelatinous gel and a preparation method and application thereof, and the method comprises the following steps: dispersing anthraquinone small molecules and porous graphene in a sodium bicarbonate solution or a phosphate buffer solution to obtain a mixture; the mass ratio of the anthraquinone small molecules to the porous graphene is 1:0.14-7; the pH value of the mixture is 8-10; and the mixture is cooled after being ultrasonically treated at 30-70 DEG C to obtain the biomass gelatinous gel. The biomass gelatinous gel is prepared by self-assembly of anthraquinone small molecules and lignin-based porous graphene as main raw materials in a weak alkaline system through non-covalent interaction between molecules. The biomass gel is a room-temperature gelatinous gel, has good temperature responsiveness, and has excellent specific capacity, remarkable shear thinning characteristics, large shear strain, self-healing characteristics, non-frequency dependence and time stability through tests.

This invention discloses a method for preparing hierarchical porous indium oxide nanotubes for lithium-ion battery anodes, comprising the following steps: Step (1) Indium salt and terephthalic acid are placed in an organic solvent and stirred evenly under oil bath conditions to obtain a homogeneous dispersion; Step (2) The homogeneous dispersion is further heated and stirred continuously to carry out the reaction, and after the reaction is completed, it is naturally cooled to room temperature to obtain a mixed reaction system; Step (3) The mixed reaction system is filtered, and the solid product obtained by filtration is washed with anhydrous ethanol and dried to obtain the precursor MIL-68(In); Step (4) The precursor MIL-68(In) is placed in a tube furnace and pyrolyzed in an air atmosphere to obtain hierarchical porous indium oxide nanotubes. This invention can solve the problems of poor cycle performance and rate performance of existing In2O3-based anode materials.

The invention provides a negative electrode material and a battery, the negative electrode material comprises an inner core and a coating layer located on at least part of the surface of the inner core, the inner core comprises graphite, the coating layer comprises a polymer, and the negative electrode material comprises at least one of an element N, an element S and an element P; the repose angle of the negative electrode material is theta degrees, the tap density of the negative electrode material is rho g / cm < 3 >, the compaction density of the negative electrode material under the pressure of 5T is T1 g / cm < 3 >, and the negative electrode material meets the formula: M = theta / rho * T1, and M is more than or equal to 105 and less than or equal to 160. According to the negative electrode material provided by the invention, the negative electrode material has high capacity, high compaction density and low expansion performance, and the fast charging performance of the negative electrode material is improved.

The invention relates to the technical field of electrochemical energy storage materials and preparation, and discloses a forestry and agricultural residue-based carbon material and application thereof in a zinc ion battery, the forestry and agricultural residue-based carbon material is prepared by taking forestry and agricultural residues as raw materials through cellulose extraction, three-dimensional skeleton construction through aerogel, high-temperature carbonization, potassium hydroxide activation pore-forming and electrochemical surface modification. The obtained carbon material has a three-dimensional hierarchical connected network structure composed of micropores, mesopores and macropores, and the surface of the carbon material is rich in oxygen-containing zinc-loving sites for inducing uniform deposition of zinc. When being used as a zinc-free negative electrode carrier of a zinc ion battery, the hierarchical pore structure effectively reduces local current density and buffers deposition volume expansion, and surface zinc-loving sites obviously reduce nucleation overpotential. Through cooperative regulation and control of a physical structure and surface chemistry, zinc dendrite growth and hydrogen evolution side reaction are effectively inhibited, coulombic efficiency, long cycle stability and rate capability of the battery are greatly improved, the process is controllable, and the cost is low.

The present application relates to the technical field of low-temperature negative electrode material preparation of lithium ion batteries, and particularly relates to a silicon-silver-indium ternary alloy thin film negative electrode material for lithium ion batteries and a preparation method thereof, the material comprises 40 at% to 99 at% of silicon, 0.1 at% to 30 at% of silver and 0.1 at% to 30 at% of indium in terms of atomic percentage. The preparation method comprises a melting metallurgy rolling process or a magnetron sputtering deposition process. In the ternary alloy system, the silver improves the electronic conductivity, the indium optimizes the lithium ion diffusion kinetics and the interface stability, and the synergistic effect of the two makes the material exhibit high capacity, high initial efficiency and good rate performance at normal temperature and low temperature. The material system has good compatibility with the above two differentiated preparation processes, and provides a solution for the large-scale and precision application of high-performance silicon-based thin film negative electrodes.

The invention provides a bimetallic nitride catalyst and a preparation method and application thereof, and relates to the technical field of catalysts.The preparation method comprises the steps that ferric nitrate and soluble starch are added into water and stirred to be gelatinized, and gelatinized liquid is obtained; adding zinc nitrate, dicyandiamide and cobalt nitrate into the gelatinized liquid, and uniformly stirring to obtain hydrogel; the hydrogel is subjected to freeze drying, and aerogel is obtained; the aerogel is placed in an ammonia atmosphere, heat preservation is conducted for 2-6 h at the temperature of 850-950 DEG C, the bimetallic nitride catalyst containing the iron-cobalt nitride is obtained, and the bimetallic nitride catalyst is high in oxygen reduction reaction activity and cycling stability.

The invention discloses a bamboo-based derived nitrogen-doped hard carbon negative electrode material and a preparation method and application thereof.The preparation method creatively utilizes the characteristic that bamboo wood is rich in natural phenolic hydroxyl groups and comprises the steps that bamboo powder and an aldehyde group compound are subjected to in-situ phenol-aldehyde polycondensation under the alkaline condition, and a cross-linked network precursor is constructed; then adjusting the pH to weak acidity, and carrying out in-situ amination doping with a nitrogen-containing compound; and finally, carbonizing to obtain the nitrogen-doped hard carbon material. According to the method, structural reconstruction and uniform nitrogen doping of the bamboo-based precursor are synchronously realized through two-step continuous molecular-level reaction of'alkaline polycondensation-acidic amination '. When the obtained material is used as a sodium ion battery negative electrode, high reversible specific capacity (greater than 304 mAh / g), high first coulombic efficiency (greater than 92%) and excellent cycling stability (300-week capacity retention rate at 0.5 C is greater than 92%) are shown. The method is simple in process, green, low in cost and suitable for large-scale production.