73 results about "Cobalt ferrite" patented technology

The invention discloses an electromagnetic shielding nanocrystalline soft magnetic complex and a preparation method thereof in the technical field of composite materials. The electromagnetic shielding nanocrystalline soft magnetic complex is prepared from the following components in parts by weight: 3-4.5 parts of graphene oxide, 6-7 parts of ferric nitrate nonahydrate, 1.9-2.2 parts of cobalt nitrate hexahydrate, 300-350 parts of nanocrystalline alloy powder and 3-4.2 parts of insulating resin. According to the method, cobalt ferrite is introduced into graphene oxide, nanocrystalline alloy powder is wrapped, a nanocrystalline double-magnetic-core shielding body of a shell-core structure is prepared, the magnetic loss capacity is improved, meanwhile, the shielding body is further wrapped with insulating resin, defects are eliminated, a compact insulating layer is formed, eddy currents among magnetic particles are restrained, and the magnetic loss capacity is improved. The electromagnetic shielding effectiveness is improved.

Provided are cobalt ferrite particles having a micrometer-order average particle diameter and similar particle diameters. The cobalt ferrite particles are obtained by a method for producing cobalt ferrite particles, including performing a thermal treatment on an aqueous solution containing a divalent iron salt and a divalent cobalt salt stabilized by a complexing agent (ferrite precursor).

The invention discloses an antibacterial composite material for water treatment and a preparation method thereof in the technical field of composite materials, and the antibacterial composite material is prepared from the following components in parts by weight: 20-25 parts of a magnetic nano material, 19-22 parts of acrylic acid, 6-9 parts of allylamine, 1.8-2.2 parts of N, N '-methylene bisacrylamide, 1.3-1.6 parts of azodiisobutyronitrile and 4.3-5.5 parts of plant polyphenol. Cobalt ferrite is used as a magnetic core to prepare a magnetic nano material to improve the recovery rate, acrylic acid and allylamine are used as polymeric monomers to form a polymer layer with high adsorption capacity, and plant polyphenols are combined on the surface, so that the adsorption performance and the catalytic decomposition performance are enhanced, and the antibacterial effect of the material is improved at the same time; further, the composite material with the functions of adsorbing heavy metal ions, decomposing organic pollutants and resisting and inhibiting bacteria is obtained.

The invention discloses a sodium alginate embedded iron-carbon microcapsule material for repairing cadmium and arsenic polluted soil and a preparation method of the sodium alginate embedded iron-carbon microcapsule material, and belongs to the technical field of soil heavy metal pollution repairing materials. The material comprises straw biochar, high-iron steel slag powder, a sulfydryl acetylated chitosan-iron monatomic cluster compound, a boron-doped graphitized carbon coated cobalt ferrite nanosheet, sodium alginate, calcium chloride and sodium carbonate. Wherein the sulfydryl acetylated chitosan is prepared by reacting chitosan with sulfydryl acetic anhydride, dialyzing and drying, and performing solvothermal reaction with ferric nitrate under high pressure. The preparation method comprises the following steps: pyrolyzing and drying the straw biochar, reacting the high-iron steel slag with sulfuric acid, adding the biochar, adjusting the pH value, adding sodium carbonate, mixing to obtain an iron-carbon-based passivation material, mixing with two modified compounds, mixing with a sodium alginate solution, dropwise adding a calcium chloride solution, and stirring and curing. The material can be applied to remediation of cadmium and arsenic polluted soil.

The invention discloses a preparation method and application of an open carbon nanotube composite film of two-dimensional graphene oxide intercalation one-dimensional packaged cobalt ferrite, and belongs to the technical field of preparation of two-dimensional material films. The invention aims to solve the problems that the catalytic effect of the existing catalytic membrane is easily interfered by natural organic matters and the selectivity on target pollutants is poor. The method comprises the following steps of: 1, preparing an open carbon nano tube for packaging cobalt ferrite; and 2, preparing the composite membrane by intercalating the two-dimensional graphene oxide. The method is used for removing organic pollutants in water. The preparation method is used for preparation and application of the open carbon nanotube composite film of the two-dimensional graphene oxide intercalation and one-dimensional packaging cobalt ferrite.

Provided are cobalt ferrite particles having a micrometer-order average particle diameter and similar particle diameters. The cobalt ferrite particles are obtained by a method for producing cobalt ferrite particles, including performing a thermal treatment on an aqueous solution containing a divalent iron salt and a divalent cobalt salt stabilized by a complexing agent (ferrite precursor).

The application belongs to the technical field of electromagnetic shielding materials, and relates to MXene / BC@CoFe2O4 electromagnetic shielding aerogel and a preparation method thereof. The electromagnetic shielding aerogel is composed of MXene, bacterial cellulose (BC) and cobalt ferrite (CoFe2O4) grown by a co-precipitation method, contains anisotropic MXene porous structure, and BC@CoFe2O4 forms a three-dimensional magnetic network. Nano-magnetic particles CoFe2O4 are grown on bacterial cellulose by a co-precipitation method; the bacterial cellulose with the nano-magnetic particles CoFe2O4 grown thereon is mixed with a MXene dispersion liquid to occur liquid self-assembly, thereby forming an aerogel precursor; and a directional three-dimensional porous structure is formed by using a liquid nitrogen directional freezing method. The magnetic particles of the MXene / BC@CoFe2O4 electromagnetic shielding aerogel can cause magnetic loss to electromagnetic waves, the MXene with good electrical conductivity causes impedance mismatch with electromagnetic waves, reflects electromagnetic waves, and the bacterial cellulose can enhance the mechanical properties of the aerogel.

The present invention discloses a preparation method and application of a bacterial cellulose-based composite nanogenerator, belonging to the field of nanogenerator and power monitoring technology. Through solution blending technology, graphene oxide and cobalt ferrite are embedded in a bacterial cellulose matrix to prepare a composite material with a stable structure. The electromagnetic properties, triboelectric properties, and mechanical stability of each composite material are systematically evaluated to screen the optimal formulation. The composite material is used to prepare a nanogenerator, and a composite structure including a friction layer and an electromagnetic induction coil is designed. By monitoring the power fluctuations output by the nanogenerator, the real-time state of the transformer's leakage magnetic field is directly reflected. The present invention utilizes the preparation method and application of the bacterial cellulose-based composite nanogenerator to achieve self-powered monitoring of power transformers, improving the accuracy and real-time performance of leakage magnetic field detection.

This application provides a sheet-like spinel cobalt ferrite, its preparation method, and its application, belonging to the field of solid oxide battery technology. In this application, a Co source and an Fe source are dissolved in deionized water, citric acid is added and stirred until homogeneous, then heated in a water bath until the solution becomes a reddish-brown transparent gel. The gel is then dried and ground to obtain a first powder. The first powder is then subjected to two CO2 laser-induced oxidation processes in air at a laser power of x to obtain a second powder. Wherein, 4W < x ≤ 10W. Finally, the second powder is washed and dried to obtain a sheet-like spinel cobalt ferrite. Compared with ordinary spinel cobalt ferrite, using the aforementioned sheet-like spinel cobalt ferrite as a cathode material in SOFC can reduce the polarization impedance of the battery by 0.023 Ωcm. 2 The maximum power density increased by 0.38 W / cm². ‑2 This improves the oxygen reduction activity and stability of SOFCs. Furthermore, using CO2 laser-induced methods simplifies the preparation process, reduces time costs, and increases production efficiency.

This invention relates to the field of hydrogen energy technology, specifically to a photocatalytic water splitting method for hydrogen production. It addresses the problems of harsh reaction conditions, low hydrogen production efficiency, and poor catalyst cycle stability in existing photocatalytic hydrogen production methods. Specifically, it uses water as the reaction medium, adds a catalyst and an electron sacrificial agent, and achieves hydrogen production through water splitting under visible light irradiation. The catalyst is prepared from cobalt ferrite, indium zinc sulfide, and biochar, and the electron sacrificial agent is triethanolamine. This method enhances the separation and transport of photogenerated carriers through the synergistic effect of the catalyst and electron sacrificial agent, resulting in high hydrogen production efficiency, strong stability, simple process, and controllable cost. Furthermore, hydrogen energy, as a zero-carbon energy source, can replace fossil fuels, reducing pollution and carbon emissions at the source, contributing to the dual carbon goals, and providing an efficient solution for large-scale hydrogen production, possessing both industrial application and ecological environmental value.

The present invention discloses an anticorrosive coating containing graphene components and a preparation method thereof. The anticorrosive coating comprises, by weight parts, 80-120 parts of waterborne epoxy resin, 1-3 parts of modified graphene, 10-30 parts of curing agent, 20-30 parts of pigment filler, 1-2 parts of leveling agent, 0.5-1 part of defoaming agent, and 0.5-1 part of dispersant; the modified graphene is polydopamine / cobalt ferrite@ graphene or cobalt ferrite@ graphene. The present invention uses polydopamine / cobalt ferrite@ graphene or cobalt ferrite@ graphene to reduce the problem that graphene is prone to agglomeration in the coating system. The coating formed by the anticorrosive coating adheres more firmly, the water permeability is reduced, and the corrosion of the coated metal is prevented. In addition, the coating formed by the anticorrosive material of the present invention has a flat, bright appearance without obvious defects such as pinholes, air bubbles, inclusions, peeling, cracks, etc. that cause the physical shielding effect of the coating to fail, and the service life of the coating can be extended.

The invention discloses a preparation method of a charcoal-loaded cobalt ferrite magnetic composite catalytic material, which is specifically implemented according to the following steps: step 1, selecting green tea as a biomass precursor, and carrying out carrier WT pretreatment; step 2, preparing a magnetic composite catalytic material of biochar loaded cobalt ferrite; step 2.1, preparing a suspension; step 2.2, preparing a solid product; step 2.3, preparing a dried precursor; and step 2.4, preparing the magnetic composite catalytic material of the biochar loaded cobalt ferrite. According to the method, the reaction rate is remarkably increased, the problem of magnetic agglomeration of active components is solved, non-free radical dominance is achieved, the anti-interference performance is high, and efficient magnetic recovery and waste utilization are achieved. The invention further discloses the magnetic composite catalytic material of the biochar loaded cobalt ferrite and application of the magnetic composite catalytic material.

The invention discloses an extraction process of chaste tree twig oil in the technical field of plant essential oil extraction. An ethanol aqueous solution is adopted for extraction, ultrasonic treatment and a composite enzymolysis technology are combined, the chaste tree twig cell structure is effectively destroyed, and the grease extraction rate is remarkably increased. And then selectively adsorbing impurities in the extracting solution by using a specially-made cobalt ferrite-deep eutectic solvent-biochar magnetic composite material, and realizing rapid separation through an external magnetic field. And the alkalescent ethanol water solution is adopted for elution, so that the structure stability of the deep eutectic solvent is protected while impurities are effectively desorbed. And finally, carrying out rotary evaporation and column chromatography refining to obtain the high-quality vitex negundo oil. The process integrates various extraction and purification technologies, has the advantages of high extraction efficiency, mild operation conditions, small environmental pollution and the like, and is particularly suitable for efficient extraction and refining of the vitex negundo oil.

This invention relates to the field of lightweight wood-plastic composite materials, specifically to an antistatic lightweight wood-plastic composite material and its preparation method, which addresses the problems of insufficient antistatic properties and high density in existing wood-plastic composite materials. The method involves mixing an antistatic agent with high-density polyethylene, extruding, cooling, crushing, and sieving to obtain an antistatic masterbatch. Modified wood flour, high-density polyethylene, maleic anhydride graft compatibilizer, antioxidant, 2-hydroxy-4-methoxybenzophenone, and γ-aminopropyltriethoxysilane are then mixed, cooled, and the antistatic masterbatch is added for further mixing. The mixture is fed into a twin-screw extruder, and cobalt ferrite-coated hollow glass microspheres are added. After extrusion, cooling, and crushing, the mixture is then subjected to secondary molding in a single-screw extruder, gradient cooling for shaping, and traction cutting to obtain the antistatic lightweight wood-plastic composite material. This material possesses excellent antistatic properties, low density, and lightweight characteristics, along with good flexural strength and impact strength, low water absorption, and excellent water resistance.

The invention discloses electromagnetic rheological copper-aluminum rolling oil as well as a preparation method and application thereof, and relates to the technical field of lubricants. The electromagnetic rheological copper-aluminum rolling oil comprises cobalt ferrite coated with titanium dioxide, base oil and an auxiliary agent. The preparation method comprises the following steps: firstly preparing titanium dioxide coated cobalt ferrite, then adding the titanium dioxide coated cobalt ferrite into base oil, then adding a surfactant, an extreme pressure agent and an antioxidant into the base oil, and mixing and stirring to obtain the electromagnetic rheological copper-aluminum rolling oil. The electromagnetic rheological copper-aluminum rolling oil has good electrorheological characteristics and magneto-rheological characteristics at the same time, and has good suspension stability; the oil film thickness, viscosity and shear stress can be adjusted by changing the parameters of the electromagnetic field, the slipping phenomenon and the scratching problem in the rolling process are reduced, and the intelligent cleaning effect is achieved; the electromagnetic rheological copper-aluminum rolling oil can be used for rolling copper, aluminum and alloys thereof.

The invention discloses a polyaluminum ferric chloride flocculant as well as a preparation method and application thereof, and belongs to the technical field of sewage treatment.The preparation method comprises the steps that cobalt ferrite is loaded on the surface of nano mesoporous silica through a coprecipitation-calcination method, supported silica is obtained, then amination modification and tartaric acid modification are performed by using a silane coupling agent KH550, and the polyaluminum ferric chloride flocculant is obtained. And finally, blending the composite silicon dioxide with an aluminum salt, an iron salt and hydrogen peroxide under an acidic condition, and forming and loading a polyaluminum ferric chloride flocculation layer on the surface through in-situ hydrolytic polymerization and catalytic oxidation synergy to obtain the polyaluminum ferric chloride flocculant. Quadruple synergy of magnetic separation, catalytic oxidation, deep adsorption and enhanced flocculation is realized, and suspended matters, soluble organic matters, phosphorus and chromaticity are efficiently removed.

The invention discloses a core-shell adsorption material for recycling precious metal in acid wastewater and a production process thereof, and relates to the technical field of precious metal adsorption and separation. Polyvinylidene fluoride is used for wrapping a magnetic material cobalt ferrite to prepare a carrier with a core-shell structure, the magnetic material cobalt ferrite is used as a core, a polyvinylidene fluoride film layer is used as a shell layer, then polyethyleneimine is grafted on the surface of polyvinylidene fluoride through a chemical reaction, and the magnetic material cobalt ferrite / polyvinylidene fluoride composite material is obtained. Finally, carboxymethyl chitosan which can adsorb palladium and platinum and is friendly to microorganisms is introduced to polyethyleneimine molecules through a chemical reaction, and efficient adsorption of palladium and platinum in the acid wastewater is achieved through cooperation of polyethyleneimine, carboxymethyl chitosan and microorganisms loaded on the surfaces of the polyethyleneimine, carboxymethyl chitosan and the microorganisms.

The invention relates to a sensitive material based on a nano-foam structure and an electrochemical hydrogen sulfide gas sensor, and a preparation method of the sensitive material based on the nano-foam structure comprises the following steps: S1, weighing Co salt and Fe salt, and dissolving the Co salt and the Fe salt in water to form a mixed solution; s2, adding glucose and urea into the mixed solution, and stirring until the glucose and the urea are dissolved to obtain a clear solution; s3, baking the clarified solution, so that the glucose and the urea are subjected to a Maillard reaction, and gas is released to form a porous nano-foam structure; s4, the porous foam is annealed so that the Co salt and the Fe salt can react, then the porous foam is naturally cooled to the room temperature after annealing, the cobalt ferrite nano-foam sensitive material is obtained, the chemical formula of the cobalt ferrite nano-foam sensitive material is Co2FeO4, and the cobalt ferrite nano-foam sensitive material is used as a sensitive material of an electrochemical H2S gas sensor. According to the embodiment of the invention, high-sensitivity, low-detection-limit, high-selectivity and high-stability detection of H2S can be realized.

The invention provides flaky spinel cobalt ferrite as well as a preparation method and application thereof, and belongs to the technical field of solid oxide batteries. The preparation method comprises the following steps: dissolving a Co source and a Fe source in deionized water, adding citric acid, uniformly stirring, heating in a water bath until the solution becomes reddish brown transparent gel, drying, and grinding to obtain first powder; secondly, CO2 laser induction is conducted on the first powder twice in the air atmosphere with the laser power being x, and second powder is obtained; wherein x is more than 4W and less than or equal to 10W. And finally, washing and drying the second powder to obtain the spinel cobalt ferrite with the flaky morphology. Compared with common spinel cobalt ferrite, the flaky spinel cobalt ferrite is applied to the SOFC as a cathode material, so that the polarization impedance of the battery can be reduced by 0.023 ohm cm < 2 >, the maximum power density can be increased by 0.38 W cm <-2 >, and the oxygen reduction activity and stability of the SOFC can be improved. In addition, by adopting the CO2 laser induction method, the preparation process is simplified, the time cost is reduced, and the production efficiency is improved.

The application relates to a cobalt ferrite nanometer magnetic material with high magnetic permeability and low loss and a preparation method thereof, and belongs to the technical field of nanometer magnetic materials. The cobalt ferrite nanometer magnetic material with high magnetic permeability and low loss is mainly prepared from the following components: ferric chloride, cobalt chloride hexahydrate, manganese chloride, zinc sulfate, modified propylene glycol alginate acid ester, lithium chloride, silicon nitride and barium carbonate. The cobalt ferrite nanometer magnetic material prepared by the application has the characteristics of high magnetic permeability and low loss.

Provided are cobalt ferrite particles having a micrometer-order average particle diameter and similar particle diameters. When a cobalt ferrite precursor is treated at a high temperature and a high pressure, an oxidation reaction is caused in the presence of a complexing agent, thereby obtaining intended cobalt ferrite magnetic particles.

The invention discloses a cobalt ferrite-loaded nitrogen-sulfur-doped porous carbon composite material and a preparation method and application thereof, and belongs to the technical field of electromagnetic wave absorbing materials. Honeycomb nitrogen-sulfur-doped porous carbon is used as a lossy material matrix, and two-dimensional metal hydroxide containing FeCo metal cations is synthesized on the surface of the lossy material matrix through in-situ growth; and performing high-temperature pyrolysis in an inert atmosphere to synchronously obtain bimetallic nano magnetic particles formed by pyrolyzing the bimetallic hydroxide, thereby preparing the magnetic porous carbonaceous composite material of FeCo magnetic particle loaded honeycomb nitrogen-sulfur doped porous carbon. The micro / nano hierarchical structure formed by the bimetallic magnetic nanoparticles and the hierarchical porous structure ensures the lightweight characteristic of the composite material, and strong magnetic loss is introduced by adding the magnetic component. The invention provides a new design thought for preparing the broadband strong-loss electromagnetic wave absorbing material by combining the double-metal hydroxide derived magnetic nanoparticles and the porous carbon material.

The invention discloses cobalt ferrite, a high-permeability iron-silicon magnetic powder core and a preparation method and application of the high-permeability iron-silicon magnetic powder core, and relates to the field of magnetic materials. The preparation method comprises the following steps: mixing and coating cobalt ferrite nanoparticles and phosphorylated magnetic powder, mixing and coating with an insulating coating agent, mixing and coating with a release agent, and carrying out compression molding and heat treatment to obtain the high-permeability iron-silicon magnetic powder core. According to the FeSi-cobalt ferrite magnetic powder core and the preparation method thereof, the FeSi soft magnetic alloy powder is subjected to insulation coating by adopting cobalt ferrite magnetism with high magnetic induction intensity, gaps among the magnetic powder can be effectively filled, the content of a magnetic medium is increased, the magnetic dilution effect is reduced, and the FeSi-cobalt ferrite magnetic powder core has high magnetic conductivity, low loss and excellent comprehensive electromagnetic performance.

The invention provides a method and system for removing high-concentration complex cyanogen in gold extraction wastewater, and relates to the technical field of sewage treatment.The method comprises the steps that the pH of the gold extraction wastewater is adjusted to 8-10, and pretreated wastewater is obtained; adding a cobalt ferrite particle catalyst into the pretreated wastewater, and introducing ozone to obtain oxidized effluent; dividing the oxidized effluent into a solution A and a solution B according to a volume ratio, oxidizing the solution A by using anaerobic ammonium oxidation bacteria under the condition of low dissolved oxygen, and mixing the oxidized solution A with the untreated solution B to obtain a mixed solution; enabling the mixed solution to react with anaerobic ammonium oxidation bacteria through a porous adsorption material, and recovering the cobalt ferrite particle catalyst for recycling. According to the method, the removal rate of the high-concentration complex cyanogen can be effectively increased, thorough mineralization of the complex cyanogen is achieved, and the core problem that the complex cyanogen is difficult to degrade is solved; and the method and the system have relatively high load resistance, are simple and convenient to operate and have good adaptability.

The invention discloses trace cobalt-doped magnetic nanoparticles as well as a preparation method and application thereof, and relates to the technical field of magnetic nano materials. According to the method, the magnetic nanoparticles are cobalt ferrite, the chemical formula of the cobalt ferrite is CoxFe3-xO4, and 0 lt; x < = 0.1; cobalt ions in the cobalt ferrite are doped in octahedral sites on the surface of the crystal lattice. And synchronous regulation and control of dynamic magnetization characteristics are realized by selectively doping cobalt ions to specific sites in crystal lattices. By accurately controlling the doping amount of cobalt, the magnetization intensity (Ms) of the magnetic nanoparticles is remarkably improved, and the relaxation time (tau) is adjusted, so that the MPI signal and MHT curative effect are remarkably improved.

The present invention relates to a process for comprehensively recovering valuable metals from cobalt-rich waste. Cobalt silicate in the waste is converted into sodium cobalt silicate through sodium carbonate roasting pretreatment, cobalt ferrite is converted into cobaltous oxide and ferric oxide, and composite oxides of tungsten, tantalum, and niobium are converted into soluble sodium salts such as sodium tungstate and sodium chromate. These are then separated from alkaline oxides such as cobaltous oxide in a subsequent water leaching process. Cobalt, iron, and copper in the water leaching residue are leached into a solution through sulfuric acid reduction leaching, while metals such as tantalum and niobium are contained in the acid leaching residue. Tungsten and chromium in the water leaching solution are separated by concentrated hydrochloric acid neutralization followed by tungsten precipitation followed by chromium reduction precipitation. This process has the advantages of a high elemental leaching rate and high separation efficiency of cobalt from elements such as tungsten and chromium. Furthermore, the process is simple, the reaction conditions are mild, and the raw materials used are inexpensive. It can achieve comprehensive recovery of elements such as cobalt, tungsten, and tantalum.

Provided are: a method for producing composite particles in which seed particles and cobalt ferrite particles can be synthesized with relatively low energy, the composite particles having a particle diameter within a specific range, having a circular shape with a predetermined average circularity, and having specific magnetic characteristics; composite particles of seed particles and cobalt ferrite particles manufactured by this manufacturing method have a circular shape having a predetermined average circularity, have specific magnetic properties, and have uniform particle diameters. The provided method for manufacturing composite particles of seed particles and cobalt ferrite particles comprises: a step in which a ferrous salt and a cobalt salt are stabilized by a complexing agent in an aqueous solution to prepare a ferrite precursor; a step in which spherical or substantially spherical seed particles are added to the ferrite precursor; and a step in which the ferrite precursor is additionally heat-treated.

This invention provides cobalt ferrite, its preparation method, and its application, belonging to the field of water treatment technology. The preparation method provided by this invention includes the following steps: (1) mixing cobalt salt, iron salt, and water to obtain a mixed solution; (2) mixing the mixed solution obtained in step (1) with an alkaline solution and carrying out a hydrothermal reaction to obtain cobalt ferrite; the temperature of the hydrothermal reaction is 155–165°C. This invention uses cobalt salt and iron salt as raw materials to prepare cobalt ferrite through a hydrothermal reaction. By controlling the temperature of the hydrothermal reaction, the obtained cobalt ferrite also contains iron(III) oxide (Fe3O4). The interaction between the two results in a faster removal rate of the prepared cobalt ferrite when used for pollutant removal in water, allowing for pollutant degradation in a shorter time. The results of the examples show that when the cobalt ferrite prepared by this invention is used to remove bisphenol A from water, its removal rate reaches nearly 100% within 5 minutes.

The invention discloses a preparation method of carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder, which comprises the following specific steps: weighing ferrite synthetic components, spherical carbonyl iron powder and tetraethoxysilane according to a ratio, the ferrite synthetic components comprise 52-56 mol% of Fe2O3 and the balance of CoO, and the spherical carbonyl iron powder and the tetraethoxysilane are mixed according to a certain ratio to prepare the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder, and the spherical carbonyl iron powder and the tetraethoxysilane are mixed according to a certain ratio to prepare the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder. The carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder is finally obtained through the steps of ball milling, stirring, drying, primary sintering, mixing, secondary sintering and the like. The method for preparing the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder is simple and convenient in process, safe and low in cost, and after the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder is used for preparing wave-absorbing products, the excellent performance of broadband strong absorption is shown in the frequency band of 2-18 GHz.

The invention discloses a multifunctional electro-catalytic material based on a cobalt ferrite nano array and a preparation method of the multifunctional electro-catalytic material in the field of electro-catalytic materials. The multifunctional electro-catalytic material is prepared from the following raw materials: a CoFe2O4 nano array substrate, ZIF-67 derived Co-N-C nano cubes and nitrogen-doped carbon nanofiber loaded Fe monatomic. The CoFe2O4 nano array substrate grows on the carbon cloth substrate through a hydrothermal method; the ZIF-67 derived Co-N-C nanocube is prepared by the following steps: stirring Co (NO3) 2.6 H2O and 2-methylimidazole in methanol, dipping a substrate, standing, drying, and calcining at 800-810 DEG C in an Ar atmosphere, thereby obtaining the ZIF-67 derived Co-N-C nanocube. According to the material, the activity and stability of OER, ORR and HER are improved through the synergistic effect of the two modified components, and the material is suitable for the field of clean energy conversion.