18 results about "Cobalt oxyhydroxide" patented technology

The invention relates to the technical field of electrochemistry, and particularly discloses a preparation method and application of hydroxyl cobalt oxide. Compared with the prior art, the preparation process of the cobalt oxyhydroxide with the large specific surface area is developed through a multi-parameter and surfactant coordinated regulation strategy, and the technical problems that the cobalt oxyhydroxide is not high in specific surface area and obvious in agglomeration phenomenon under the existing synthesis technology are solved; the hydroxyl cobalt oxide prepared by the method has good water electrolysis performance as a water electrolysis oxygen evolution reaction cathode material, and has good charge-discharge performance and cycling stability as a supercapacitor material.

This invention discloses a continuous and efficient method for preparing nano-sized cobalt hydroxyl oxide and cobalt tetroxide, and their applications. The method includes the following steps: (1) adding a cobalt salt solution, an oxidant, and a precipitant to a complexing agent and a solvent, and stirring to obtain a reactant; (2) drying the reactant at 150-160°C to obtain the cobalt hydroxyl oxide; and drying the reactant at 220-230°C to obtain the cobalt tetroxide. Compared with batch production methods, the continuous method of this invention has higher production efficiency, and the prepared cobalt hydroxyl oxide has advantages such as large specific surface area, easy crushing, and small particle size.

The invention discloses a cobalt complex pre-catalyst for electrocatalytic oxygen evolution and a preparation method thereof, and relates to the technical field of functional complexes. The structure of the cobalt complex pre-catalyst (CotPBA-anion) is formed by coordination of a cobalt coordination cation unit chelated by tPBA and an anion; the structure of the catalyst is CoOOH / tPBA, and the catalyst is characterized in that the catalyst is cobalt oxyhydroxide loaded by an organic ligand. Wherein the CoOOH / tPBA reconstructed by using the CotPBA-Cl shows the optimal electrochemical activity and stability. The pre-catalyst is simple in preparation process and mild in reaction condition, and shows good electro-catalytic oxygen evolution reaction activity and electrochemical stability after simple reconstruction.

The invention discloses doped large-particle hydroxyl cobalt oxide as well as a preparation method and application thereof. The preparation method of the doped large-particle cobalt oxyhydroxide comprises the following steps: dissolving cobalt salt and doped metal salt in water to prepare a mixed salt solution; under the stirring condition, the mixed salt solution and the precipitator solution are added into a reactor in a parallel flow mode, the pH of a reaction system is controlled to be 8.0-11.0, the temperature is controlled to be 40-70 DEG C, aging is carried out after charging is completed, a co-precipitation reaction is carried out, and doped precursor slurry is obtained; and adding an oxidizing agent into the doped precursor slurry, carrying out oxidation reaction at 60-95 DEG C, and filtering, washing and drying the product after the reaction is finished. The hydroxyl cobalt oxide prepared by the method is large particles of 10-50 microns, has good fluidity, is easy to be filled in a fixed bed, can be directly used for a flowing type electrolytic tank, and solves the engineering application problem of nano powder.

The invention provides a method for high-valued utilization of a positive electrode material of a waste lithium cobalt oxide battery, and belongs to the technical field of cyclic utilization of positive electrode materials of waste batteries. The lithium cobalt oxide powder in the positive electrode material of the waste lithium cobalt oxide battery is subjected to acid leaching to obtain the cobalt-containing leaching solution, then the cobalt-containing leaching solution is directly subjected to hydrothermal reaction with urea and ammonium fluoride to obtain the intermediate, the intermediate reacts with the oxidizing agent to obtain the hydroxyl cobalt oxide, metal separation steps such as extraction and reverse extraction are not needed, the method is simpler, and the cost is lower. And the prepared hydroxyl cobalt oxide has excellent catalytic performance.

The application relates to the technical field of catalysts, and particularly discloses a hydrogenation catalyst as well as a preparation method and application thereof.A hydrogenation catalyst raw material comprises a carrier component and a catalytic component; the carrier component raw material comprises: 60-80 parts of gamma-alumina; 5-10 parts of titanium carbide; 5-10 parts of hydroxyapatite; 10-15 parts of chelated nanocapsules; 5-10 parts of zirconium oxide; and 3-5 parts of a stabilizer; the catalytic component raw material comprises: 20-30 parts of modified hydroxyl cobalt oxide; 5-10 parts of molybdenum trioxide; and 1-3 parts of rare earth oxide.The modified hydroxyl cobalt oxide is obtained by modifying hydroxyl cobalt oxide with lanthanum nitrate.The hydrogenation catalyst can avoid pollution and poisoning of the catalytic active component by the components such as the rare earth oxide, and realizes long-term stability of the catalytic performance.

The present application relates to a kind of detection of sweat glucose porous hydrogel film and preparation, detection method, porous hydrogel film includes: carrier, cobalt oxyhydroxide modified rare earth nanoparticles and glucose oxidase;The cobalt oxyhydroxide modified rare earth nanoparticles and the glucose oxidase are distributed in the inside of the carrier;The cobalt oxyhydroxide is coated on the surface of the rare earth nanoparticles to form the cobalt oxyhydroxide modified rare earth nanoparticles;The cobalt oxyhydroxide is used to quench the fluorescence emission of the rare earth nanoparticles;The carrier is formed by polyacrylamide intercrossing.This application detects glucose in sweat by the principle of fluorescence resonance energy transfer, with the advantages of high efficiency and stability, safe and simple to use, the structure of porous hydrogel film is simple, easy to make and low in cost, the detection of sweat glucose is realized by observing the fluorescence intensity of film, and it can also work in dark environment.

The invention discloses a supported annular hydroxyl cobalt oxide carbon dioxide adsorption material and a preparation method and application thereof.During preparation, carbon cloth serves as a working electrode, a carbon rod serves as a counter electrode, electrochemical deposition is carried out in the presence of a reference electrode and an electrolyte, an annular hydroxyl cobalt oxide precursor is generated on the carbon cloth, and the supported annular hydroxyl cobalt oxide carbon dioxide adsorption material is obtained; then, the intermediate is soaked in an alkaline solution, and a carbon dioxide adsorption material is generated; the electrolyte comprises cobalt salt, boric acid and water; the carbon dioxide adsorption material comprises carbon cloth and annular hydroxyl cobalt oxide combined with the carbon cloth; the adsorption material has high specific surface area, multi-effect adsorption site coordination and excellent cycle stability, shows high CO2 adsorption capacity and outstanding cycle retention rate in a normal-temperature environment, and is suitable for high-efficiency trapping of low-concentration CO2 in flue gas in high-emission industries such as electric power and chemical engineering; and a new material path is provided for industrial popularization of a low-cost and high-stability carbon capture technology.

The application discloses an integrated metal electrode and a preparation method and an electrocatalytic synthesis ammonia method, relates to the technical field of electrocatalytic synthesis ammonia, and solves the problems of poor structural and interface stability of the existing electrode under fluctuating power conditions, easy attenuation of ammonia yield and faradic efficiency, and lack of electrode preparation and ammonia synthesis complete technology suitable for fluctuating working conditions. The electrode takes foamed iron, cobalt or nickel as a substrate, and has an active phase in situ grown on the surface; the active phase is ferric oxyhydroxide, cobalt oxyhydroxide or nickel hydroxide. The foamed metal is pretreated, and the foamed metal is subjected to CV circulation in an alkaline electrolyte at 1.4-0.6V in a three-electrode system to obtain the integrated metal electrode. The integrated metal electrode is used as a working electrode, an alkaline solution containing nitrite is used as an electrolyte, and the nitrite is reduced and electrocatalytically synthesized into ammonia under the condition of constant current with fluctuating current density in a three-electrode electrolysis system. The application can be used for electrocatalytic reduction and synthesis of ammonia from nitrite under fluctuating power conditions.

The invention discloses large-particle high-aluminum-doped spherical hydroxyl cobalt oxide, cobaltosic oxide and a preparation method thereof. The preparation method of the large-particle high-aluminum-doped spherical cobalt oxyhydroxide comprises the following steps: preparing a cobalt-aluminum mixed solution, a precipitant solution, a complexing agent solution and a reaction base solution containing a seed crystal; adding the cobalt-aluminum mixed solution, the precipitant solution and the complexing agent solution into the reaction base solution containing the seed crystal in a parallel flow manner, and carrying out a co-precipitation reaction; and after the specified particle size is reached, carrying out solid-liquid separation and drying to obtain the large-particle high-aluminum-doped spherical hydroxyl cobalt oxide. By optimizing coprecipitation process parameters, uniform distribution of the aluminum element is achieved, meanwhile, it is ensured that the product has high tap density, narrow particle size distribution and good sphericity degree, when the obtained material is applied to a high-voltage lithium cobalt oxide positive electrode, the gram volume, cycling stability and high-temperature performance of the high-voltage lithium cobalt oxide positive electrode can be remarkably improved, and the service life of the high-voltage lithium cobalt oxide positive electrode is prolonged. The core pain point of non-uniform doping of a traditional carbonate system is solved.

The application provides a method for rapidly and efficiently preparing aluminum-magnesium uniformly doped hydroxyl cobalt oxide, which comprises the following steps: adding an aluminum salt and a magnesium salt into a cobalt ion-containing aqueous solution to obtain a first mixed solution; slowly adding hydrogen peroxide into the first mixed solution under rapid stirring to obtain a second mixed solution; adding the second mixed solution and a sodium hydroxide solution into a reaction container in a certain proportion under stirring, and obtaining a product containing a precipitate by controlling feeding time, reaction temperature and reaction time; and finally, obtaining a target product through solid-liquid separation, washing and drying. The aluminum-magnesium uniformly doped hydroxyl cobalt oxide prepared by the method has the advantages of small particle size, high specific surface area, uniform doping and controllable doping amount, etc.; the preparation process is simple and rapid, and the aluminum-magnesium elements can be uniformly doped under the conditions of rapidness and low energy consumption, and the phenomenon of element aggregation is avoided, so that the method has certain popularization and application prospects.

The application discloses a cobalt oxyhydroxide catalyst, a preparation method thereof and a CoOOH / PTFE catalytic membrane, and belongs to the technical field of advanced oxidation water treatment.The CoOOH catalyst is prepared by using CoSO4.7H2O, (NH4)2S2O8 and K2SO4 as raw materials and adopting a hydrothermal method, and has a three-dimensional porous flower ball shape; due to the special morphology of the material, the removal rate of EE2 catalyzed by PMS can be as high as 95% or more, which is 2.39 times of the CoOOH prepared by a conventional precipitation method and 5.96 times of commercial Co3O4; the CoOOH material activated PMS catalyzed EE2 also has wide pH adaptability (pH: 3.0-10.0), cycle stability and low cobalt ion leaching concentration (0.0019 mg / L). In addition, the CoOOH material is loaded on a PTFE membrane by a vacuum filtration technology, a CoOOH / PTFE membrane-PMS system is built, and the system is applied to the continuous degradation of EE2 in actual water bodies, can be continuously treated for 24 hours, and can maintain a removal rate of 92.48%, and has potential practical application value.

The invention provides a continuous aluminum-doped cobalt oxyhydroxide preparation method, which comprises: continuously introducing an aluminum-doped cobalt salt solution mixed with a complexing agent and a precipitating agent into a reaction kettle, continuously introducing air, carrying out a reaction, controlling the temperature, the pH value, the flow rate and the stirring rotation speed of the reaction system, and stopping the reaction when the liquid level reaches an overflow port, continuously overflowing the slurry into an aging tank, carrying out aging treatment, and filtering and drying to obtain aluminum-doped hydroxyl cobalt oxide; the temperature of the reaction system is 60-80 DEG C, and the pH value is 9.8-11.2; the molar ratio of the complexing agent to the aluminum element in the aluminum-doped cobalt salt solution is (0.016-0.032): 1; the molar ratio of the Al element to the Co element in the aluminum-doped cobalt salt solution is (0.05-0.1): 1. By optimizing the technological process and reaction conditions, continuous, stable and efficient production of the aluminum-doped hydroxyl cobalt oxide is realized, and the uniformity, sphericity and tap density of the product are remarkably improved.

A composite is provided which comprises planar molybdenum oxide microstructures and cobalt oxyhydroxide microstructures disposed on the planar molybdenum oxide microstructures. A method of forming the composite is also provided. The composite is used in the fabrication of an electrochemical sensor, which comprises the composite, an electrode, and a polymeric coating. The electrochemical sensor is used in a method of detecting the presence of glucose in an analyte. The method involves applying a voltage to the electrochemical sensor relative to a counter electrode and measuring a current response. The method in insensitive to common oxidative interfering analytes such as urea, lactate, and NaCl.

The application discloses an electrochemiluminescence sensor for high-sensitivity detection of bisphenol A and a construction method thereof, and relates to the field of electrochemistry, and comprises the following steps: incubating a D-UiO-66@CsPbBr3 composite material with a first nucleic acid aptamer S1; incubating a CoOOH@Au composite material with gold nanoparticles reduced on the surface of cobalt oxyhydroxide nanosheets with a second nucleic acid aptamer S2 of bisphenol A; based on specific binding between the aptamer and bisphenol A, using the defect type UiO-66 loaded with CsPbBr3 as a base luminous material, and reducing the Au nanoparticles on the surface of the cobalt oxyhydroxide nanosheets as an ECL energy transfer acceptor to quench the ECL signal; when the bisphenol A exists, the specific recognition of the aptamer makes the energy acceptor separate from the electrode surface, so that the ECL signal is recovered; and the electrochemiluminescence sensor constructed through layer-by-layer modification has good reproducibility, high sensitivity and a low detection limit.

The application discloses an indium trioxide nanotube loaded cobalt oxyhydroxide composite material and application of the composite material in detection of nitrogen oxide, and the composite material is obtained by uniformly mixing indium trioxide nanotubes and Co / MOF in an aqueous solution, adding an etchant to fully react, washing the reaction product to neutral, and then drying to obtain the composite material; the organic skeleton raw material in the Co / MOF is dimethyl imidazole; and the etchant is sodium hydroxide or potassium hydroxide. The method has the advantages of simple process, low cost and no pollution to the environment; the indium trioxide nanotube has the advantages of excellent conductivity, large surface area and chemical stability, and the synthesized low-cost sensing material has high response value at room temperature, rapid detection and good stability, and has excellent selectivity to nitrogen oxide; the composite material has excellent gas sensing performance, and has excellent long-term stability and cycle stability, and has wide application prospect in the field of detection of nitrogen oxide.

The application discloses a nickel-hydrogen battery and a preparation method thereof. The nickel-hydrogen battery comprises a positive electrode and a negative electrode; the positive electrode comprises a positive electrode base body and a positive electrode material loaded on the positive electrode base body, and the negative electrode comprises a negative electrode base body and a negative electrode material loaded on the negative electrode base body; the positive electrode material comprises a nickel-containing substance, a metal oxide, a cobalt oxyhydroxide and a positive electrode binder; the nickel-containing substance comprises cobalt-coated spherical nickel hydroxide and nickel hydroxide, and the metal oxide is selected from one or more of zinc oxide, titanium oxide and yttrium oxide; and the negative electrode material comprises a La-Y-Ni hydrogen storage alloy, a conductive agent, a negative electrode binder and yttrium oxide. The nickel-hydrogen battery has a high charge retention rate.

The invention discloses flaky hydroxyl cobalt oxide and a preparation method thereof. The preparation method of the flaky hydroxyl cobalt oxide comprises the following steps: dispersing soluble cobalt salt into water to prepare a solution A, and dispersing an oxidizing agent and alkali into water to prepare a solution B; raising the reaction temperature to 70-80 DEG C, and introducing the solution B into the solution A at a first stirring speed for a first time; at a second stirring rotating speed, continuously introducing the solution B for a second time; stopping feeding, and continuing for a third time at a third stirring rotating speed to obtain a reaction solution; and carrying out solid-liquid separation, washing, drying and crushing on the reaction liquid to obtain the flaky hydroxyl cobalt oxide. The hydroxyl cobalt oxide with good dispersity and a unique sheet structure can be formed without a complexing agent and a dispersing agent by controlling the dosage of the oxidizing agent and the precipitating agent and the stirring speed. The preparation method disclosed by the invention is simple, few in control conditions, free of residue after the oxidant is used, high in product purity, high in repeatability and suitable for industrial large-scale production.