652results about "Cobalt oxides/hydroxides" patented technology

The invention discloses a method for synchronously improving the recovery rate of copper and cobalt in high-oxidation-rate copper-cobalt ore and low-grade copper oxide-cobalt concentrate, which comprises the following steps: (1) carrying out copper sulfide flotation on the high-oxidation-rate copper-cobalt ore to obtain high-copper tailings; (2) the low-grade copper-cobalt concentrate and the high-copper tailings are mixed according to the mass ratio of 1: (1-2), and mixed ore is obtained; (3) the obtained mixed ore and a sulfuric acid solution system leaching agent are stirred and mixed, and slurry is obtained; (4) leaching the obtained slurry at normal temperature, and carrying out solid-liquid separation to obtain leached residues and leached liquid; (5) carrying out washing, extraction, reverse extraction and electrodeposition on the obtained leaching residues to obtain metal copper; and removing iron from the raffinate, and adding magnesium oxide into the iron-removed liquid for precipitation to obtain crude cobalt hydroxide. According to the method, the high-copper tailings and the low-grade copper oxide cobalt concentrate are subjected to the processes of ore blending, size mixing, normal-temperature sulfuric acid leaching and the like, the final copper leaching rate is 95% or above, and the cobalt leaching rate is 70% or above.

The invention discloses a CoFeCuMn LDH nanosheet, a confinement catalytic membrane and a preparation method of the CoFeCuMn LDH nanosheet. The preparation method of the CoFeCuMn LDH nanosheet comprises the steps that A1, cobalt salt, ferric salt, copper salt and manganese salt are dissolved in pure water according to a preset proportion to prepare a first solution, sodium hydroxide is dissolved in pure water to prepare a second solution, and sodium carbonate is dissolved in pure water to prepare a third solution; a2, adding the first solution and the second solution into the third solution, and stirring to obtain a mixed solution; a3, carrying out hydrothermal reaction on the mixed solution; a4, centrifugally washing the product obtained in the step A3 to obtain a precipitate; and A5, the sediment is dried, and the CoFeCuMn LDH nanosheet is obtained. According to the CoFeCuMn LDH nanosheet, the confinement catalytic membrane and the preparation methods of the CoFeCuMn LDH nanosheet and the confinement catalytic membrane, the degradation efficiency and the degradation rate of new pollutants are remarkably improved.

The invention belongs to the technical field of lithium ion battery materials, and particularly relates to cobalt carbonate and a preparation method thereof, cobaltosic oxide and a lithium ion battery. The crystal grain size of the cobalt carbonate (104) crystal face is 200-250, and the median particle size Dv50 is 16-20 [mu] m. The preparation method of the cobalt carbonate comprises the following steps: adding a precipitant solution and a cobalt salt solution into a reaction kettle in a parallel flow manner, carrying out a co-precipitation reaction, controlling the reaction pH value, starting a thickener when the volume of a material in the reaction kettle reaches a target value, continuing the reaction until large-particle cobalt carbonate slurry is obtained, and carrying out solid-liquid separation and washing to obtain the cobalt carbonate. Cobalt carbonate is subjected to first sintering, mixed with a doping agent and then subjected to second sintering, and cobaltosic oxide with the (311) crystal face grain size being 660-700 and the median particle size Dv50 being 14-18 microns is prepared. The cobaltosic oxide is high in mechanical strength and good in reaction activity with a lithium source, and the prepared lithium cobalt oxide positive electrode material is relatively excellent in electrochemical performance.

The invention discloses cobaltosic oxide, a preparation method thereof, lithium cobalt oxide, a positive pole piece and a battery, and relates to the technical field of lithium battery positive pole materials. The Dv50 of the cobaltosic oxide, the grain size D (111) of the (111) crystal face and the specific surface area BET meet the following relation: 3.33 [mu] m < 3 > / g < = # imgabs0 # < = 6.90 [mu] m < 3 > / g, wherein the Dv50 of the cobaltosic oxide is 3-20 [mu] m. The cobaltosic oxide is obtained by pre-sintering and calcining cobalt carbonate with the crystallinity of 30%-80% and the median particle size Dv50 of 3-22 [mu] m; the reaction activity of the cobaltosic oxide and a lithium source is high, the mechanical property is good, the lithium ion diffusion rate of the obtained lithium cobalt oxide is high, and the specific capacity and the first charge-discharge efficiency are relatively high.

The invention discloses a bifunctional CoCu catalyst, a preparation method thereof and application of the bifunctional CoCu catalyst in sulfur and ammonia production. A Cu-doped CoOOH bifunctional electrocatalyst is synthesized on foam cobalt (CF) through an in-situ growth method and is used for a cathode NO3RR and an anode SOR at the same time. In a sulfur oxidation reaction, the cobalt-based catalyst can effectively oxidize sulfur or a compound thereof into a substance with a higher valence state, such as sulfate, so that removal and conversion of sulfur are realized. In addition, due to low cost and environmental friendliness of the catalyst, the catalyst has great application potential in the aspect of electrochemical coupling treatment of sulfur and nitrate pollutants. Therefore, the invention designs a bifunctional electrocatalyst capable of simultaneously exerting the advantages of Cu-based and cobalt-based catalysts, and is expected to realize efficient electrochemical coupling treatment of sulfur and nitrate.

The invention relates to the field of gas sensors, and discloses a hydrogen sulfide gas sensor and a method for detecting the concentration of hydrogen sulfide in gas. The hydrogen sulfide gas sensor comprises a substrate and a gas sensitive material, a cavity is formed in the substrate, the gas-sensitive material is located above the cavity, and the two ends of the gas-sensitive material are connected with the gold electrodes on the substrate; the gas sensitive material comprises graphene fiber and metal oxide loaded on the graphene fiber. The metal oxide is selected from one or more than two of oxides of Zn, Cd, Cu, Ni, Pd, Pt, Co, Ir, Fe, Mn, Cr, Mo, W, V, Ti, Mg and Al; the specific surface area of the gas sensitive material is 80-150m < 2 > / g; the loading capacity of the metal oxide is 0.05 to 5 weight percent. The hydrogen sulfide gas sensor can be self-heated, has high sensitivity to hydrogen sulfide gas, and is suitable for being applied to the field of gas monitoring.

The invention belongs to the field of material preparation and chemical engineering, and particularly relates to an N-doped modified MOFs (Metal-Organic Frameworks) derived core-shell nanoreactor as well as a preparation method and application thereof. The preparation method comprises the following steps: taking cobalt as a node metal, synthesizing an N-doped modified MOFs material with an organic ligand and a nitrogen source through a hydrothermal reaction, then coating the surface of the material with porous silicon dioxide, and preparing the N-doped modified MOFs derived core-shell nanoreactor through a two-step calcination method. The MOFs derived core-shell nanoreactor prepared by the invention has a large specific surface area, a rich pore structure and excellent catalytic activity and stability, and is high in catalytic activity, good in recycling stability and suitable for large-scale popularization and application when being used as a catalyst for alpha, beta-unsaturated aldehyde transfer hydrogenation.

The invention relates to a NiCoW-CoP / Co3O4 (at) NF self-supporting heterostructure catalyst and a preparation method thereof. The preparation method comprises the following steps: preparing a CoP-coated NF precursor on foamed nickel through a constant potential electrodeposition method, then carrying out annealing treatment in a muffle furnace, and finally carrying out electrodeposition on NiCoW-LDH to obtain the NiCoW-CoP / Co3O4-coated NF material. According to the preparation method, the microsphere material with the surface covered with the dendritic dendrites is synthesized, and exposure of active sites is increased through the special surface structure of the microsphere material. The compounding of the trimetal hydroxide containing high-valence tungsten and the introduction of oxygen vacancies can effectively enhance the local electron density of oxygen atoms on the surface of the catalyst, thereby enhancing the catalytic performance and seawater corrosion resistance of the material. Compared with the prior art, the method disclosed by the invention is simple to operate and low in cost, and the prepared catalyst has high electrocatalytic activity, relatively low hydrogen evolution overpotential and oxygen evolution overpotential and long-time stability. And the method has important theoretical significance and potential application value for developing a bifunctional electrocatalyst suitable for electrolyzing seawater.

The invention discloses cobalt hydroxide and a preparation method and application thereof, and belongs to the technical field of battery materials. The preparation method comprises the following steps: carrying out precipitation reaction on a soluble cobalt salt solution, a precipitant solution and a complexing agent solution; the precipitant is a NaOH solution; the complexing agent is a surfactant, and the surfactant comprises at least one of sodium dodecyl benzene sulfonate, sodium dodecyl sulfate, hexadecyl trimethyl ammonium bromide, polyoxyethylene polyoxypropylene ether, polyvinylpyrrolidone, polyethylene glycol and the like. The method is simple to operate, the process is easy to control, the cobalt hydroxide which is different in size and has a unique space-staggered nanosheet structure can be obtained by regulating and controlling the surfactant, the utilization rate of active substances can be increased, the charge-discharge cycle life can be prolonged, and the conductivity and the charging efficiency of the electrode can be improved. The thermal stability and the structural stability of the positive electrode material can be improved by taking the material as a coating layer, and the interface reaction between the positive electrode material and electrolyte is inhibited, so that the cycling stability is enhanced.

The invention relates to a method and a system for preparing a battery metal oxide precursor through nitrate spray pyrolysis. The method comprises the following steps: preparing a metal nitrate mixed solution; atomizing and spraying the metal nitrate mixed solution into a reaction furnace, and performing pyrolysis through different heating temperature zones in the reaction furnace to obtain a metal oxide mixture and high-temperature flue gas; the high-temperature flue gas is subjected to waste heat recovery treatment and then enters a regeneration device to be recovered, and regenerated nitric acid is obtained; the metal oxide mixture is subjected to secondary heating at the bottom of the reaction furnace. The metal oxide precursor is prepared through spray pyrolysis, and compared with a traditional coprecipitation calcination process, the method is more economical and lower in operation cost; and different heating temperature zones are adopted for pyrolysis, so that the application range is wider, and the device can be suitable for metal nitrate at different pyrolysis temperatures.

The present invention discloses a lithium-rich manganese-based positive electrode material and a preparation method thereof, and a lithium-ion battery. The method comprises: mixing and dissolving a manganese source, a cobalt source and a lithium source to obtain a metal salt solution; adding an organic phosphorus sulfide, a complexing agent and a dispersant to react to obtain a precursor solution; adding a lithium hydroxide solution, and aging after a precipitation reaction; heat-treating, washing and drying the precipitate after aging; mixing the dried precipitate with a lithium source, and sintering in sections to obtain a lithium-rich manganese-based positive electrode material. The lithium-rich manganese-based positive electrode material and a preparation method thereof, and a lithium-ion battery provided by the present invention can adjust the migration of cobalt and lithium ions under different electrochemical states by forming a nano-scale dynamic interface inside the material by cobalt and lithium, and avoid the passivation phenomenon after doping in the prior art; and introducing phosphorus-sulfur groups into the material system can effectively stabilize the lattice structure of the material and improve the conductivity of the material by improving the efficiency of electron and ion transmission.

The invention discloses a preparation method of a metal-doped cobalt-based oxide material, which comprises the following steps: metal nitrate is dissolved in glycerol and isopropanol, a solvothermal method is adopted for reaction to obtain a reaction product, the metal in the metal nitrate comprises cobalt and at least one of nickel, copper, iron or molybdenum, the concentration of cobalt nitrate in the dissolved solution is 0.001-0.05 mM, and the concentration of cobalt nitrate in the solution is 0.01-0.05 mM; the concentration of metal nitrate except cobalt is 0.1-1 mu M; the reaction product is subjected to high-temperature calcination, the metal-doped cobalt-based oxide material with the microstructure being nanospheres with rough surfaces is obtained, the reaction temperature of the solvothermal method is 120-180 DEG C, and the reaction time is 3-6 h. The invention also discloses the metal element doped cobalt-based oxide material obtained by the preparation method and application of the metal element doped cobalt-based oxide material in electrocatalytic nitrate reduction synthesis of ammonia. The preparation method provided by the invention is simple, and the prepared metal-doped cobalt-based oxide material shows excellent electrochemical performance when applied to electrocatalytic nitrate reduction synthesis of ammonia.

The invention discloses a ruthenium-doped nanoneedle sheet carbon-loaded cobaltosic oxide self-supporting electrode as well as a preparation method and application thereof. The preparation method comprises the following steps: preparing a ruthenium-cobalt precursor from a mixed solution of cobalt nitrate hexahydrate, ammonium fluoride, ruthenium trichloride and urea through a hydrothermal method, drying, and calcining in air to obtain the RCO catalyst grown on the carbon cloth. The catalyst has a nanoneedle sheet type structure, can provide a high-quality reactant transmission channel, shows excellent oxygen evolution reaction electrocatalytic activity and stability in alkali / acidic electrolyte, can be used as an efficient anode catalyst for acid and alkaline solution water electrolysis devices, and has a good market prospect.

The invention belongs to the technical field of electrochemical sensors, and particularly relates to a cobalt-based modified industrial solid waste vinegar residue derived carbon composite material and a preparation method and application thereof. The preparation method comprises the following steps: washing, drying, crushing and sieving industrial waste vinegar residues to obtain vinegar residue powder; carbonizing the vinegar residue powder in an inert atmosphere to obtain carbonized vinegar residues; the carbonized vinegar residues are mixed in a hot alkali solution for activating treatment, and then Co3O4 is derived through inorganic cobalt salt in-situ growth ZIF-67, so that the cobalt-based modified industrial solid waste vinegar residue derived carbon composite material is obtained. Porous activation is carried out on the surface of the carbonized vinegar residues through hot alkali, rich protruding wrinkles and pores are formed, the surface area is increased, rich nitrogen components and active carbon oxygen functional groups are reserved, and the catalytic reaction activity is improved. The material is used as a sensing material to prepare a high-performance electrochemical biosensor, and the constructed electrochemical sensor is used for detecting biomolecules such as hydrogen peroxide and the like to obtain a relatively wide detection range.

The invention discloses a cobaltosic oxide catalyst doped with lanthanide metal, a preparation method of the cobaltosic oxide catalyst and application of the cobaltosic oxide catalyst to ammonia production through nitrate reduction. The method comprises the following steps: carrying out hydrothermal reaction on cobalt nitrate hexahydrate and a lanthanide metal salt precursor in a mixed system of isopropanol and glycerol, and then carrying out high-temperature calcination to prepare the lanthanide metal-doped cobaltosic oxide catalyst. The preparation method disclosed by the invention is simple to operate and low in cost, the prepared lanthanide metal-doped cobaltosic oxide catalyst shows excellent Faraday efficiency, ammonia yield and cycling stability in an electro-catalysis nitrate reduction reaction, a traditional path of preparing ammonia from nitrate is broken through, and more efficient performance is realized.

The invention relates to composite-form aluminum-doped cobalt carbonate as well as a preparation method and application thereof. The preparation method comprises the following steps: preparing a first carbonate solution, a second carbonate solution and an aluminum-doped cobalt salt solution; under the stirring condition, the aluminum-doped cobalt salt solution and the first carbonate solution are added into the second carbonate solution for a pre-reaction, and a reaction solution containing cobalt carbonate seed crystals is obtained; an aluminum-doped cobalt salt solution and a first carbonate solution are continuously added into the reaction solution, a first reaction and a second reaction are sequentially carried out, composite-form aluminum-doped cobalt carbonate particles are obtained, the second reaction comprises a first stage and a second stage, the mass ratio of the aluminum-doped cobalt salt solution to the first carbonate solution in the first stage is 1: 1-2: 1, and the mass ratio of the aluminum-doped cobalt salt solution to the second carbonate solution in the second stage is 1: 1-2: 1; and in the second stage, the mass ratio of the aluminum-doped cobalt salt solution to the first carbonate solution is (0.10: 1)-(0.25: 1). According to the preparation method disclosed by the invention, uniform dispersion of an outer-layer aluminum sheet is realized, and the uniformity of aluminum doping in cobalt carbonate is improved.

The invention discloses a preparation method of a metal atom doped cobaltosic oxide electrolyzed water catalyst, and relates to a preparation method of an electrolyzed water catalyst. The invention aims to solve the problems of high cost, slow reaction in an acid environment and relatively high overpotential of the existing electrolytic water oxygen evolution catalyst prepared from noble metals and compounds thereof. The preparation method comprises the following steps: 1, dissolving cobalt nitrate in a solvent, and uniformly stirring; 2, adding the metal salt into the solvent, and uniformly stirring; and 3, sequentially dropwise adding to the surface of the carbon cloth, then heating and preserving heat, and cooling in air after heat preservation. The method is used for preparing the metal atom doped cobaltosic oxide electrolyzed water catalyst.

The invention relates to a coprecipitation method for preparing cobaltosic oxide, which comprises the following steps: mixing a cobalt salt solution, a precipitant solution and a complexing agent solution in a carbonate base solution in a parallel flow manner, and carrying out first coprecipitation reaction to a first particle size to obtain a seed crystal; the cobalt salt solution, the precipitant solution and the complexing agent solution are mixed in a parallel flow mode, a second coprecipitation reaction is conducted, and cobalt carbonate powder is obtained; calcining the cobalt carbonate powder to obtain cobaltosic oxide with a median particle size D50 of 18-20 [mu] m; a complexing agent in the complexing agent solution is iminodiacetic acid. According to the invention, by using the specific complexing agent, cobalt ions exist in the system in the form of complex ions and are slowly released in the reaction process, so that the first coprecipitation reaction can be carried out orderly, and the cobaltosic oxide with the median particle size D50 of 18-20 [mu] m can be obtained.

The present application belongs to the field of new energy, and discloses a waste lithium ion battery crushing, sorting, and recycling method, comprising the following steps: step 1, crushing a lithium ion battery and heating, to obtain a first solid; step 2, removing a housing, to obtain a second solid; step 3, sieving the second solid, to obtain a first undersize product and a first oversize product; step 4, performing airflow sorting on the first oversize product to remove a separator, to obtain a third solid; step 5, pyrolyzing the first undersize product and the third solid, to obtain a fourth solid; step 6, sieving the fourth solid, to obtain a second undersize product and a second oversize product; and step 7, crushing and sieving the second oversize product, to obtain a third undersize product and a third oversize product. By means of collecting black powder before and after crushing in step 7, the present method implements black powder grading, thereby facilitating targeted treatment of black powder of different grades. The black powder recovery rate and the collection efficiency of the present application are high, and a separator is efficiently removed. Furthermore, the present application also discloses a system suitable for said method.

The present invention discloses a silicon-carbon negative electrode material modified with a magnetic transition metal oxide and a preparation method thereof, and belongs to the technical field of lithium-ion battery micro-nano materials. The preparation method provided by the present invention has readily available raw materials, low prices, a simple preparation process flow, easy operation, low energy consumption, and environmental friendliness in the preparation process. The prepared silicon-carbon negative electrode material has a uniform and dense modified layer containing a magnetic transition metal oxide, which can effectively improve the conductivity, high specific capacity, and cycle stability of the silicon-carbon negative electrode material. The first coulomb efficiency reaches more than 80%, and the specific capacity can be stabilized to a maximum of 1127mAh / g after 100 cycles, which is much higher than the current average level of this type of material. In addition, the prepared silicon-carbon negative electrode material has excellent mechanical flexibility and can be directly used in the assembly of lithium-ion batteries, and has strong application potential in flexible wearable electronic devices in the future.

The invention provides a sulfo-spinel composite catalyst, a preparation method thereof and an electrolyzed water catalyst. The preparation method comprises the following steps: adding a carrier into a mixed solution of cobalt salt, a morphology regulator and a precipitator, carrying out hydrothermal reaction, washing and drying to obtain a cobalt precursor; the cobalt precursor is subjected to calcination treatment, and a Co3O4 catalyst is obtained; mixing the Co3O4 catalyst with a sulfur source solution, carrying out vulcanization reaction, washing and drying; and mixing a product of the sulfuration reaction with a reducing agent, carrying out reduction treatment, washing and drying to obtain the sulfo-spinel composite catalyst. The invention also provides the sulfo-spinel composite catalyst obtained by the preparation method, and an electrolyzed water catalyst containing the sulfo-spinel composite catalyst. The catalyst has relatively high OER catalytic activity and HER catalytic activity.

The present disclosure belongs to the technical field of cobalt hydroxide preparation. Disclosed are a preparation method for and the use of a cobalt hydroxide nanosheet. The preparation method comprises: mixing first liquid caustic soda and water to prepare a base solution; under a protective atmosphere, adding in a parallel flow manner a cobalt salt solution, second liquid caustic soda and a silane coupling agent to the base solution so as to carry out a reaction, controlling the reaction pH to be 12-13 during the parallel flow process, and obtaining a cobalt hydroxide slurry after the reaction is completed; and carrying out solid-liquid separation on the cobalt hydroxide slurry, washing the obtained solid material, and drying and crushing same to obtain a cobalt hydroxide nanosheet.

The present disclosure belongs to the field of batteries, and particularly relates to cobalt hydroxide and a preparation method therefor, a positive electrode material, a battery and electrical equipment. Provided in the present disclosure is cobalt hydroxide, the particles of which are in the shape of a sheet and have an average thickness of 10-20 nm. The cobalt hydroxide of the present disclosure is nanosheets having an extremely small average thickness and a larger surface area, which can thus improve the coating effect thereof on a positive electrode material, thereby effectively inhibiting the formation of a nickel oxide rock salt-like phase in the positive electrode material, reducing the concentration of residual lithium on the surface of the positive electrode material and enabling lithium ions to be quickly deintercalated / intercalated; therefore, the electrical properties of the positive electrode material prepared therefrom can be significantly improved.

The invention discloses an MXene quantum dot tip heterojunction material with high photothermal conversion efficiency. The MXene quantum dot tip heterojunction material comprises a substrate and a Co3O4 nanoneedle array structure grown on the substrate in situ, ti3C2MXene quantum dots are loaded on the surface of the Co3O4 nanoneedle, and the Ti3C2MXene quantum dots are fixed on the surface of the Co3O4 nanoneedle through the interaction force of heterogeneous charges. The invention also discloses a preparation method of the MXene quantum dot tip heterojunction material. The preparation method comprises the following steps: (1) preparing a Co3O4 nanoneedle structure arranged in an array on a substrate by using a hydrothermal method; and (2) under the irradiation of an ultraviolet lamp, putting the product in the step (1) into an MXene quantum dot solution, and soaking for 6-8 hours.

The invention provides spherical cobaltosic oxide as well as a preparation method and application thereof, the preparation method comprises the following steps: (1) injecting a cobalt salt-containing solution and a carbonate solution into a base solution in a parallel flow manner for a coprecipitation reaction to obtain a mixed-phase precursor; and (2) calcining the mixed phase precursor to obtain the spherical cobaltosic oxide, wherein the solute of the base solution in the step (1) is alkali metal hydroxide. According to the method disclosed by the invention, the precursor of the hydroxyl cobalt oxide and cobalt carbonate mixed phase can be prepared without separating kettles, the content of foreign ions in the precursor is low, and small-particle and high-purity cobaltosic oxide can be prepared by directly sintering.

The present application provides a preparation method of a cobalt-coated lithium nickel manganese oxide cathode material. By means of an in-situ coprecipitation method, a trace amount of cobalt coating layer is constructed on the surface of the precursor. The interfacial stability is improved by using the electron conduction enhancement effect of cobalt, and the cobalt-free property of the material bulk is retained, so that the material has a complete crystal structure. When applied to a lithium-ion battery, it has good discharge specific capacity and cycling performance. The first-cycle discharge capacity reaches 193.52 mAh / g, and the 250-cycle retention rate reaches 90.38%. The electrochemical stability is significantly enhanced. The present application also provides a cobalt-coated lithium nickel manganese oxide cathode material and a lithium-ion battery.

The invention discloses a preparation method and application of a Co-based two-dimensional metal oxide gas sensing material, and the preparation method comprises the following steps: reacting, centrifuging, drying and calcining a mixture containing an amine compound, a surfactant and a cobalt precursor to obtain the Co-based two-dimensional metal oxide gas sensing material, the calcination is carried out in an inactive atmosphere; the Co-based two-dimensional metal oxide in the Co-based two-dimensional metal oxide gas sensing material is CoO. According to the invention, the nano two-dimensional metal oxide is applied to the triethylamine gas sensor for the first time, and rapid, efficient and high-sensitivity detection of triethylamine gas at a relatively low temperature is realized. The two-dimensional structure improves the specific surface area of the material, and provides convenience for electron transmission.

The invention relates to the field of materials, and discloses a three-dimensional graphene / metal oxide composite pellet and a preparation method and application field thereof, the three-dimensional graphene / metal oxide composite pellet comprises a graphene pellet and a metal oxide loaded on the graphene pellet; wherein the specific surface area of the three-dimensional graphene / metal oxide composite sphere is 50-500m < 2 > / g. In the obtained three-dimensional graphene / metal oxide composite sphere, the metal oxide is uniformly loaded on the surface of the graphene sphere, and the sphere internally has a rich pore structure, so that the application of gas sensing, catalysis, energy storage and the like is facilitated.

The invention discloses a lithium iron phosphate modified material as well as a preparation method and application thereof, and belongs to the technical field of battery materials. The lithium iron phosphate modified material provided by the invention comprises lithium iron phosphate particles, a coating layer coating at least part of the surface of the lithium iron phosphate particles, and a carbon layer coating at least part of the surface of the coating layer, the coating layer comprises a transition metal doped layer, and the transition metal doped layer contains structural defects. On the basis of improvement of a lithium iron phosphate material, the transition metal doped layer is introduced, doped transition metal elements can generate holes or electrons in the material, and then structural defects such as oxygen defects are formed, so that absorption of the material to oxygen is promoted, and adverse effects caused by oxygen release of a lithium supplementing agent are reduced.

The invention belongs to the technical field of lithium ion batteries, and particularly relates to a composite positive electrode material for a lithium ion battery and a preparation method of the composite positive electrode material. The composite positive electrode material is composed of a positive electrode base material, a lithium supplementing material and a catalytic material. The preparation method comprises the following steps: (1) preparing a composite material of the positive electrode base material and the lithium supplementing material in situ; and (2) dispersing the catalytic material on the surface of the composite material of the positive electrode base material and the lithium supplementing material, and forming a stable interface layer between the catalytic material and the lithium supplementing material. According to the method disclosed by the invention, the lithium supplementing material has double functions of surface modification of a positive electrode base material and lithium supplementing of a negative electrode, and meanwhile, the first effect and the cycling stability of the battery are improved; a catalytic material is introduced to the surface of the lithium supplementing material, free O generated by the lithium supplementing material Li is fixed in situ, the bag expansion phenomenon of the battery is relieved, and the cycling stability and safety of the battery are further improved; the preparation process is simple, raw materials are cheap and easy to obtain, the production cost is low, and industrial production and popularization are easy.