317results about "Cobalt oxides/hydroxides" patented technology

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 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 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 application discloses a method for selectively extracting metals from waste ternary lithium batteries by using a eutectic solvent. The method uses a eutectic solvent DES synthesized by choline chloride and oxalic acid as an extraction agent, quotes dimethyl sulfoxide DMSO and water as diluents, introduces a circulation and extraction step on the basis of metal element series immersion, i.e. extracts lithium oxalate from the leaching solution with ethanol and recycles the DES by fractional distillation, and makes innovations in recycling of metal lithium and recycling of the DES. The application has the advantages of high efficiency extraction, high precision purification, innovative extraction of lithium element and innovative recovery of the reagent DES.

The invention provides high-aluminum doped cobalt carbonate and a preparation method and application thereof, and the preparation method comprises the following steps: (1) injecting a cobalt-aluminum mixed salt solution, a carbonate solution and an organic weak acid solution into a base solution in a parallel flow manner, and carrying out a co-precipitation reaction to obtain a precursor; and (2) stopping injection of the organic weak acid solution, continuing to inject the cobalt-aluminum mixed salt solution and the carbonate solution, and carrying out a co-precipitation reaction to obtain the high-aluminum doped cobalt carbonate. According to the method, through segmented coprecipitation and control of the types of precipitants used for coprecipitation of all the segments, the doping amount and uniformity of aluminum in cobalt carbonate can be improved, aluminum segregation is avoided, and meanwhile high-aluminum-doped cobalt carbonate higher in sphericity degree and better in compactness can be obtained.

The invention discloses a modified cobaltosic oxide catalyst and a preparation method and application thereof.The catalyst comprises a carrier foamed nickel, tungsten and chlorine co-doped cobaltosic oxide nanosheets W and Cl-Co3O4, the tungsten and chlorine co-doped cobaltosic oxide nanosheets W and the Cl-Co3O4 are loaded on the carrier, cobalt chloride and tungsten salt serve as precursors of the catalyst, and the tungsten and chlorine co-doped cobaltosic oxide nanosheets W and the Cl-Co3O4 are loaded on the carrier. The preparation method comprises the following steps: firstly, carrying out a hydrothermal reaction to obtain a nickel foam loaded tungsten-doped basic cobalt chloride nanosheet W-Co2 (OH) 3Cl2, and then carrying out in-situ conversion on the Co2 (OH) 3Cl2 into a nickel foam loaded tungsten and chlorine co-doped cobaltosic oxide nanosheet W, Cl-Co3O4 through calcination. According to the invention, chlorine and tungsten are introduced into cobaltosic oxide, so that the activity and stability of electrocatalytic oxygen evolution are improved, and the cobaltosic oxide is used as an anode catalyst for electrocatalytic seawater decomposition and has excellent activity and stability of electrocatalytic oxygen evolution.

The present application provides a cathode lithium supplement material, a cathode electrode sheet containing the material, and an electrochemical device. The cathode lithium supplement material includes: a matrix of xLi₂O·yM and carbon present on the matrix; wherein x > 0, 0.4x ≤ y ≤ 2x, and M includes at least one of Mn, Fe, Co, Ni, Cu, Cr, or V. The cathode lithium supplement material has strong chemical stability and can effectively improve the particle agglomeration phenomenon during the slurry mixing process. Applying the cathode lithium supplement material in the cathode electrode sheet can achieve the supplement of active lithium and effectively improve the energy density of the electrochemical device.

The present invention discloses a MOF-derived cobalt trioxide @ cobalt oxide @ cobalt diphosphide composite material and its preparation method and application, which belongs to the technical field of MOF-derived composite materials. It includes: the present invention synthesizes Co‑MOF‑74 by a hydrothermal method, then in-situ oxidation under an air atmosphere, and then in-situ partial phosphating under an argon atmosphere, and the obtained sample is Co3O4@CoO@Co2P composite photocatalyst. The advantage of the present invention is that the composite photocatalyst prepared with rod-shaped Co‑MOF‑74 as a template inherits the regular rod-shaped morphology and porous structure of the MOF precursor, provides more contact and reaction sites for surface charge and mass transfer in the photocatalytic reaction, and promotes the migration and separation of photogenerated carriers. The preparation process of the method of the present invention is simple, the reaction conditions are suitable, it is suitable for large-scale promotion, and has good application prospects in the fields of environment, energy, etc.

The invention relates to the field of nano materials and photonic crystal materials, in particular to nano particles, preparation of the nano particles and application of the nano particles in self-assembly of three-dimensional non-close-packed photonic crystals. The nanoparticles can be self-assembled into a three-dimensional non-close-packed photonic crystal in a concentration range of 1 wt%-60 wt%. According to the invention, the problem that the self-assembly of the three-dimensional non-close-packed colloid photonic crystal is difficult to realize at low concentration at present is solved. By adjusting the mass fraction of the particles in a solution, the three-dimensional non-close-packed colloidal photonic crystal with rich colors can be formed through self-assembly, and the three-dimensional non-close-packed colloidal photonic crystal has wide application prospects in the fields of sensing, display and the like.

This invention belongs to the field of lithium-ion battery technology, specifically relating to a composite cathode material for lithium-ion batteries and its preparation method. The composite cathode material consists of three parts: a cathode matrix material, a lithium replenishment material, and a catalyst material. The preparation method is as follows: (1) preparing a composite material of the cathode matrix material and the lithium replenishment material in situ; (2) dispersing the catalyst material on the surface of the composite material and forming a stable interface layer between the catalyst material and the lithium replenishment material. Through the method of this invention: the lithium replenishment material has both surface modification of the cathode matrix material and lithium replenishment of the negative electrode, simultaneously improving the battery's initial efficiency and cycle stability; introducing the catalyst material onto the surface of the lithium replenishment material in situ fixes the free O generated by the Li release from the lithium replenishment material, alleviating the battery swelling phenomenon and further improving the battery's cycle stability and safety; moreover, the preparation process is simple, the raw materials are cheap and readily available, the production cost is low, and it is easy to promote industrial production.

The invention belongs to the field of batteries, and particularly relates to sulfur-doped cobaltosic oxide as well as a preparation method and application thereof. The sulfur-doped cobaltosic oxide is micron-sized spherical particles of which the bulk phase is uniformly doped with a sulfur element, and at least part of the sulfur element is doped into an oxygen site of a cobaltosic oxide lattice. The sulfur-doped cobaltosic oxide provided by the invention can effectively improve the gram volume and cycle performance of the lithium ion / sodium ion battery, and has a wide application prospect.

Provided is a method for separating impurities and cobalt without using an electrolysis process from a cobalt chloride solution containing impurities and producing a high purity cobalt sulfate. The production method for cobalt sulfate includes: a copper removal step (S1) of adding a sulfurizing agent to a cobalt chloride solution containing one or more impurities of copper, zinc, manganese, calcium, and magnesium and generating a precipitate of sulfide of copper to separate to remove copper; a neutralization step (S2) of adding a neutralizer or a carbonation agent to a cobalt chloride solution having undergone through the copper removal step (S1) and generating cobalt hydroxide or basic cobalt carbonate to separate magnesium; a leaching step (S3) of adding sulfuric acid to the cobalt hydroxide or the basic cobalt carbonate to obtain cobalt sulfate solution; and a solvent extraction step (S4) of bringing an organic solvent containing an alkyl phosphoric acid-based extractant to the cobalt sulfate solution and extracting zinc, manganese, and calcium into the organic solvent to separate to remove zinc, manganese, and calcium. These steps are sequentially executed.

A method for preparing a two-dimensional porous oxide belongs to the technical field of porous oxide preparation. The method includes the following steps: (1) using a metal salt as a precursor, an ion-intercalated two-dimensional oxide is prepared by a molten salt method; (2) the ion-intercalated two-dimensional oxide is mixed with a lithium initiator, reacted for a predetermined time, and then the unreacted lithium initiator is removed, filtered, and washed to obtain the two-dimensional porous oxide. The two-dimensional porous oxide prepared by this method forms uniform pores with a pore size range of 2-10 nm and a specific surface area of ​​200-300 m². 2 / g.

The present invention discloses a method for preparing highly doped aluminum cobalt oxide, comprising the following steps: preparing a mixed solution A containing a cobalt salt, an aluminum salt, and a complexing agent; the complexing agent being a mixture of a soluble sulfide and a soluble phosphate; adding the mixed solution A and an alkaline solution to a bottom solution, adjusting the pH, controlling the reaction temperature, and reacting to obtain a reactant B; filtering and washing the reactant B, performing a first calcination and subsequent washing; then performing a second calcination and screening to obtain the product. The product prepared by the method of the present invention utilizes a mixture of sulfide and phosphate as a dual complexing agent instead of an ammonia complexing agent, significantly improving the environmental pollution of the production process and effectively reducing environmental treatment costs. The prepared product has a more uniform morphology, good particle consistency, a high specific surface area, and can achieve an aluminum content of up to approximately 10,000 ppm of cobalt oxide.

The application discloses a kind of foam nickel supported copper-cobalt bimetallic composite catalyst and preparation method and application, belong to electrocatalytic material technical field.CuSO4·5H2O, CoSO4·7H2O and C6H5Na3O7 are mixed and using constant voltage deposition method is loaded on foam nickel substrate, and CuCo / NF precursor is obtained, and copper-cobalt bimetallic composite catalyst Cu x O-Co3O4 / NF with excellent catalytic activity and stability is successfully prepared by temperature programmed calcination.The application significantly enhances the adsorption capacity of nitrate molecules on the catalyst surface by utilizing the synergistic effect of Cu and Co, reducing the incidence of side reactions, thereby improving the catalytic efficiency of nitrate reduction reaction.Compared with traditional single catalyst, it shows higher ammonia yield, Faraday efficiency (FE) and better stability, and has broad application prospect.

The invention discloses a material reactor, a material reaction system, a method for decomposing a self-oxidation reduction precursor and application. The material reactor comprises a dividing piece and a reaction cylinder, adjusting the rotation of the reaction cylinder; the reaction cylinder is provided with a reaction cavity along the length direction; the dividing piece is placed in the reaction cavity; the dividing piece is provided with at least three dividing plates; one ends of the plurality of sub-plates are connected and are distributed in a surrounding manner by taking the connected position as the center; the other ends of the partial split plates are in contact with the inner wall of the reaction cavity; the material reaction system comprises a rack, a heating device, a feeding device, a discharging device and a material reaction system, according to the scheme, multiple synergistic effects of preventing adhesion, improving heat transfer and accelerating gas-solid reaction can be realized, and the problem of waste caused by the fact that gas decomposed by raw materials does not participate in synthesis and is directly discharged in a production process is solved.

The invention belongs to the technical field of food safety detection, and particularly relates to a histamine molecular imprinting electrochemical sensor based on a carbon-based nano composite material and a preparation method and application of the histamine molecular imprinting electrochemical sensor. Aiming at the problems of poor selectivity, high detection limit or complicated operation and the like of the existing histamine detection technology, a Co3O4 / N-HCS (cobaltosic oxide / nitrogen-doped hollow carbon sphere) composite material is prepared by adopting a solvothermal method, o-phenylenediamine (o-PD) is taken as a functional monomer, a molecularly imprinted polymer membrane (MIP) is constructed on the surface of a glassy carbon electrode (GCE) by adopting an electropolymerization method, and the histamine detection electrode is prepared. The MIP / Co3O4 / N-HCS / GCE sensor with specific recognition sites on histamine is formed. The sensor has high selectivity, high sensitivity and good stability, is simple and convenient to operate and rapid in detection, can efficiently realize accurate detection of histamine in food, and is suitable for safety monitoring scenes of various foods such as fermented food, aquatic products and dairy products.

This invention discloses a sheet-like porous cobalt chloride, a single-crystal cobalt tetroxide, a single-crystal lithium cobalt oxide, and their preparation methods and applications, belonging to the field of battery materials technology. The chemical formula of the sheet-like porous cobalt chloride is M. x Co 1‑x Cl2, 0≤x≤0.5, M is a metallic element other than cobalt; the tap density of this sheet-like porous cobalt chloride is not less than 1 g / cm³. 3 Specific surface area not less than 1.8m² 2 / g、D v10 Not less than 4.5μm, D v50 Not less than 8.5μm, D v90 The diameter is not less than 20 μm. This sheet-like porous cobalt chloride has a high tap density, a large specific surface area and pore volume, and a relatively uniform pore size, which is beneficial to increasing sintering activity. Moreover, when it is mixed with lithium source for calcination, its sheet-like porous structure is also conducive to the uniform diffusion of lithium ions into the bulk phase of the material, making the lithium ion distribution more uniform, which in turn helps to improve the electrochemical performance of the cathode material and the battery.

The invention discloses a method for preparing vinyl chloride by electrocatalytic dechlorination of 1, 2-dichloroethane, a working electrode of the method takes a metal oxide as a catalyst, and the metal oxide is selected from at least one of the following metal oxides: Pd, Mn, Fe, Co, Ni, Cu, Ru and Mo. According to the invention, the metal oxide powder is used as the electrocatalyst, the catalyst is coated on the electrode material to prepare the working electrode, the working electrode is applied to electrocatalytic dechlorination reaction of 1, 2-dichloroethane, vinyl chloride can be generated at high selectivity at room temperature, a new way is opened up for production of vinyl chloride by electrocatalytic dechlorination, and the method has wide application prospect. And a green and low-cost solution is provided for efficient synthesis of vinyl chloride.

The present application mainly relates to the technical field of pollution gas prevention and treatment, and particularly relates to a preparation method and application of a transition metal oxide catalyst for high-efficiency catalytic decomposition of N2O pollution. The preparation method is as follows: a specific surfactant is dissolved in deionized water, inorganic acid is added, stirring is performed until the mixture is miscible, transition metal nitrate is added, reaction is performed until a gel is formed, drying is performed to obtain a dry gel, calcination is performed, and the target catalyst is obtained. The prepared catalyst 10TX-Co3O4 has extremely high low-temperature catalytic activity, and the catalytic conversion rate of N2O reaches 90% at 300 DEG C; and under the condition of coexistence of O2, NO x , H2O impurity gas and N2O (simulated tail gas of a nitric acid plant), the catalyst still has high catalytic activity and stability (81% conversion rate at 400 DEG C). The present application provides a plurality of high-activity low-temperature catalysts for catalytic decomposition of N2O, and provides a wider train of thought for subsequent design of the catalyst and effective development and utilization of the additives.

The application relates to the technical field of lithium ion batteries, in particular to a coated ternary positive electrode material and a preparation method and application thereof. The coated ternary positive electrode material comprises a ternary positive electrode material and a coating layer on the surface of the ternary positive electrode material, and the coating layer comprises an aluminum oxide chemically modified cobalt compound layer; in the coating layer, the molar ratio of aluminum oxide and the cobalt compound is (0.001-2):100. The provided coated ternary positive electrode material can improve the specific capacity and cycle performance of a battery.

The application discloses a kind of cubic system tricobalt tetroxide quantum dots solvent hot preparation method, comprising the following steps: the mixture is obtained by mixing with set proportion with the source of cobalt, alcohol, polyvinylpyrrolidone, deionized water and hydrogen peroxide;The mixture is heated to a preset temperature in a sealed container with a predetermined volume ratio and isothermal reaction for a set time;When the reaction is finished, the reaction product is cooled to room temperature and washed, and the cubic system tricobalt tetroxide quantum dots are obtained after drying.The cubic system tricobalt tetroxide quantum dots with specific crystal structure can be obtained under the optimal preparation conditions, and the tricobalt tetroxide quantum dots with high uniformity of particle size and particle dispersion can be obtained;It can be applied in catalysis, energy storage and sensing fields, and the preparation process is simple and easy to operate, with good repeatability, low energy consumption and low cost, and the process parameters can be scaled up or down, suitable for industrial mass production.

The present invention belongs to the field of catalyst preparation technology, specifically to a method for preparing a CoNiFe-based catalyst for hydrogen production by water electrolysis. A CoNiFe-based precursor is first calcined to obtain a metal oxide powder, which is then mixed with carbon black and ball-milled before secondary calcination to obtain the CoNiFe-based catalyst. This catalyst is then loaded onto a carbon paper surface as a working electrode to construct a three-electrode system for water electrolysis, exhibiting dual catalytic performance for both OER and HER.

The present application provides a graphite negative electrode material and its preparation method and application. The graphite negative electrode material comprises graphite, a hard carbon layer coated on the surface of the graphite, and a metal oxide layer coated on the surface of the hard carbon layer; wherein the graphite negative electrode material satisfies the relationship: d 002 represents the carbon layer spacing of the graphite negative electrode material, ρ represents the compaction density of the graphite negative electrode material, SSA represents the specific surface area of ​​the graphite negative electrode material, T hard represents the average thickness of the hard carbon layer, T metal Represents the average thickness of the metal oxide layer. In this application, the hard carbon layer is a fiber-based hard carbon layer, obtained by carbonizing organic fibers. It bonds evenly with graphite, exhibits good strength, has high interfacial stability, and can reduce the specific surface area of ​​graphite. The metal oxide layer can improve the electronic conductivity and initial coulombic efficiency of the material. Furthermore, the hard carbon layer and the metal oxide layer can work synergistically to effectively improve the rate performance and specific capacity of the graphite negative electrode material.

This work innovatively realizes the effective regulation of the crystalline / amorphous crystal surface by subjecting the phosphide to low-temperature liquid nitrogen quick freezing treatment, and prepares a thin-sheet CoO x / CoP-L catalyst and its preparation method, the preparation method is simple to operate, low cost, and has better economic benefits. x The crystalline / amorphous heterogeneous interface formed by the CoP-L flakes effectively promotes the adsorption and desorption of water during hydrogen evolution, while the lattice distortion optimizes the CoO x The electronic structure of / CoP‑L ultimately achieves improved performance and exhibits excellent performance in hydrogen evolution reactions in both alkaline and acidic media. Under alkaline and acidic conditions, only 56.6mV and 98mV overpotentials are required, respectively, to drive 10mA cm ‑2 It is worth noting that the alkaline HER process has a current density of 68 mA cm ‑2 The catalytic activity begins to exceed that of commercial Pt / C electrode, showing excellent catalytic potential.

The invention provides a regeneration method and application of a nickel-cobalt-manganese ternary material precursor based on raw material recycling. The regeneration method comprises the following steps: crushing a nickel cobalt lithium manganate positive plate disassembled from a waste battery, and screening to obtain positive powder; calcining the positive electrode powder in a hydrogen atmosphere, and dissolving a calcined solid product in water to obtain a leachate and a solid mixture; mixing the solid mixture with dilute sulphuric acid, and reacting at a certain temperature to obtain leachate and hydrogen; adding ammonia water into the leachate to obtain a chelate, adjusting the pH value through sodium hydroxide to precipitate the chelate, and performing solid-liquid separation to obtain a precursor and a waste liquid; distilling the waste liquid to collect ammonia gas and water vapor; and (5) electrolyzing the residual liquid in the distillation in the step (5), collecting sodium hydroxide in a cathode chamber after electrolysis, and collecting dilute sulfuric acid in an anode chamber. The regeneration method not only has a high regeneration rate, but also can ensure the cyclic utilization of the raw materials, so that no medicine waste or waste water tail treatment process exists.

The invention provides a preparation method of a CoO / CoP-LIG heterojunction electrolyzed water catalyst, and belongs to the technical field of preparation methods of electrocatalytic materials. CoO and CoP in the obtained electro-catalysis material are of a heterostructure, a large number of active interfaces and defect sites are exposed between the two components, and the electro-catalysis reaction is facilitated. The laser induced graphene (LIG) has excellent conductivity and huge specific surface area, and an ideal platform is provided for loading of CoO / CoP heterojunction nanosheets and construction of electron / mass transfer channels. The water electrolysis catalyst is simple in preparation process, high in stability, low in raw material price, easy to realize industrial mass production, and beneficial to realizing industrial development of hydrogen production by water electrolysis. The electrolyzed water catalyst can also be applied to degradation of urea in industrial and agricultural pollutants, and is an environment-friendly electrolyzed water catalyst.

The invention relates to a preparation method of ultrathin two-dimensional cobalt oxide rich in oxygen vacancies and an application of the ultrathin two-dimensional cobalt oxide rich in oxygen vacancies in food total antioxidant capacity detection, and belongs to the fields of low-dimensional nano materials, biological mimic enzyme catalysis and analytical chemistry. According to the preparation method, cobalt acetylacetonate and hexadecyl trimethyl ammonium bromide are adopted as raw materials, and the ultrathin two-dimensional cobalt oxide nano-enzyme rich in oxygen vacancies is prepared through a hydrothermal reaction and high-temperature pyrolysis. The obtained ultrathin two-dimensional cobalt oxide nano-enzyme rich in oxygen vacancies has excellent peroxidase-like catalytic activity and selectivity. The oxygen-vacancy-rich metal oxide has the advantages of high stability, easy mass production and low preparation cost, and is expected to be widely used in the fields of biosensing, agriculture, food engineering, catalysis and the like.

The invention relates to the technical field of electrocatalysis, in particular to a defect-rich cobaltosic oxide electrocatalyst and a preparation method and application thereof.The preparation method includes the steps that cobalt nitrate and di-methylimidazole are dissolved and centrifuged through solvation to obtain a precursor, then the precursor and potassium bromide are annealed together, finally, washing is conducted, and the defect-rich cobaltosic oxide electrocatalyst is obtained; the defect-rich cobaltosic oxide electrocatalyst can be obtained through vacuum drying, and the defect-rich cobaltosic oxide electrocatalyst has excellent water desorption oxygen desorption reaction electrocatalytic activity and stability and has the potential of large-scale industrial application.

An acetone sensor based on boron-doped cobalt tetroxide with an amorphous / crystalline heterostructure, as well as its preparation method and application, belongs to the field of gas sensor technology. The sensor consists of an Al2O3 ceramic tube substrate, two parallel and separate annular Au electrodes coated on the outer surface of the ceramic tube substrate, a gas-sensitive film coated on the outer surface of the ceramic tube and the annular Au electrodes, and a nickel-chromium alloy heating coil passing through the interior of the ceramic tube. The gas-sensitive film is made of boron-doped cobalt tetroxide with an amorphous / crystalline heterostructure. This unique amorphous / crystalline heterostructure not only maintains the stable structure of the crystalline material but also leverages the advantages of the amorphous structure, such as high electron delocalization and a large number of reaction sites, thereby improving the acetone gas-sensing performance of the cobalt tetroxide material. The resulting sensor has high sensitivity to acetone and a low detection limit, and has good application prospects.