702 results about "Cobalt salt" patented technology

The invention relates to a preparation method of Pt monatomic nano-enzyme and application of Pt monatomic nano-enzyme in cardiac troponin I. The preparation method comprises the following steps: 1) ultrasonically dispersing cobalt salt, selenium powder, chloroplatinic acid, urea and sodium chloride in an alcohol solvent, heating and stirring until the solvent is completely volatilized to obtain a solid mixture, and grinding the solid mixture into powder; and 2) placing the powder in a heating device, carrying out Joule heat treatment in an air atmosphere, washing a reactant, and carrying out vacuum drying to obtain the Pt monatomic nano-enzyme. Se doping is introduced in the one-step chemical reaction process to construct oxygen vacancies, rapid heating and structural shaping are achieved in combination with Joule heat treatment, the Se-doped Co3O4-loaded Pt monatomic catalyst is obtained, the oxygen vacancies and Se doping sites are synergistically used as anchoring sites, Pt monatomic atoms are effectively fixed, and the loading capacity and dispersity of the Pt monatomic atoms are improved. The obtained material shows excellent POD-like enzyme activity, can be used for constructing a high-sensitivity colorimetric immunoassay system, and realizes rapid and accurate detection of cTnI.

The invention belongs to the technical field of catalysts, and relates to a surface-reconstructed heterojunction catalyst and a preparation method and application thereof. The preparation method comprises the following steps: dissolving cobalt salt, ferric salt and praseodymium salt in deionized water, heating and spraying on a carrier to prepare praseodymium-doped ferrocobalt layered double hydroxide; mixing the praseodymium-doped ferrocobalt layered double hydroxide with a phosphorus source, and calcining in an inert atmosphere to prepare praseodymium-doped CoP / Fe2P; and carrying out electrooxidation treatment on the praseodymium doped CoP / Fe2P, so as to prepare the Pr6O11 cluster modified CoFeOOH heterojunction catalyst. Through cooperation of three technologies of spray thermal deposition, phosphating and electrooxidation, stable construction and electrochemical activation of a heterogeneous interface are realized, the corrosion resistance and chlorine evolution resistance competitive capacity of the catalyst in a chlorine-containing alkaline system are remarkably improved, the current density of 100 mA. Cm <-2 > can be achieved only through 223 mV overpotential, and meanwhile, stable operation is performed for 500 h.

The invention relates to a sunken porous magnetic alloy ball wave-absorbing material and a preparation method and application thereof.The wave-absorbing material is prepared through the following steps that S1, citric acid, soluble ferric salt, soluble cobalt salt and soluble nickel salt are dissolved in a mixed solvent of ethylene glycol and water, and the mixture is fully stirred to form a uniform mixed solution; and S2, the mixed solution obtained in the step S1 is subjected to spray drying, obtained precursor powder is placed in the air atmosphere to be calcined to remove the carbon source, then the precursor powder is placed in the H2 / Ar atmosphere to be subjected to heating reduction, and the porous FeCoNi alloy balls with the surface pits are obtained and are the target product. The surface of the prepared alloy microsphere has an obvious concave structure, magnetic anisotropy and magnetic performance are enhanced, a small number of pores are generated in the reduction process, impedance matching of the material is optimized, and effective high-frequency electromagnetic absorption is achieved; and due to the synergistic effect of the recesses and the pores, the obtained alloy microspheres have obvious lightweight characteristic, and have good application prospects in the field of electromagnetic absorption.

The invention discloses a preparation method of CoWO (cobalt tungsten oxide) modified NbOp-n heterojunction NbO5 / CoWO photocatalyst powder. The preparation method comprises the following steps: dissolving cobalt salt and tungsten salt in deionized water, stirring and mixing, carrying out hydrothermal reaction in an autoclave, washing and drying to obtain CoWO powder; the preparation method comprises the following steps: dissolving niobium oxalate and ammonium carbonate in deionized water, adding CoWO powder, carrying out a hydrothermal reaction in an autoclave, and carrying out washing and drying treatment to prepare NbO / CoWO photocatalyst powder. According to the method, the hydrothermal reaction temperature is regulated and controlled, and the mass ratio of raw materials is optimized, so that the catalyst forms a p-n heterojunction structure of NbOmicron flower loaded CoWOnano particles. The prepared catalyst has high norfloxacin wastewater degradation efficiency under visible light irradiation, has the advantages of simple preparation process, low reagent cost, high catalytic activity and good structural stability, and can be effectively applied to purification treatment of antibiotic polluted water.

The invention discloses a catalytic electrode which comprises a substrate, and an anti-corrosion layer and a sulfur-phobic layer which are sequentially attached to the substrate, the substrate is a blank foamed nickel substrate, the anti-corrosion layer is formed by dipping the foamed nickel substrate with a ferric salt solution, and the sulfur-phobic layer is formed by processing a precursor with a cobalt salt solution through electro-deposition. Accordingly, a corresponding preparation method is also established, a blank foamed nickel substrate is adopted, firstly, the foamed nickel substrate is subjected to dipping treatment with an iron salt solution to obtain a precursor with an anti-corrosion layer, and then the precursor is subjected to electro-deposition treatment with a cobalt salt solution to form the sulfur-phobic layer on the anti-corrosion layer. Wherein the anti-corrosion layer can isolate a high-sulfur environment and prevent the substrate from being corroded; the sulfur phobic layer may prevent sulfur products from depositing and passivating the electrode. The catalytic electrode provided by the invention solves the problems of sulfur reaction corrosion and passivation, shows excellent catalytic activity and stability, and can be used for catalyzing sulfur oxidation reaction for a long time. In conclusion, the method has the advantages of mild conditions, simple process, economy and practicability, and has obvious large-scale industrial production potential.

The invention discloses an efficient NiMo-Co MOF alkaline electrolysis water electrode and a preparation method thereof.The efficient NiMo-Co MOF alkaline electrolysis water electrode comprises a nickel net, a NiMo deposition layer deposited on the nickel net and a Co MOF deposition layer deposited on the NiMo deposition layer, and during preparation, the nickel net is pretreated firstly; dissolving a nickel salt, a molybdenum salt, a conductive salt and a complexing agent in water to obtain a NiMo electro-deposition solution; the method comprises the following steps: dissolving cobalt salt and a ligand in a mixed solution of DMF and water to obtain a Co MOF electro-deposition solution; the pretreated nickel net is placed in a NiMo electro-deposition solution for constant-current deposition, and a NiMo electrode with a NiMo deposition layer loaded on the nickel net is obtained; the NiMo electrode is placed in the Co MOF electro-deposition solution for constant-voltage deposition, and the NiMo-Co MOF composite electrode with the Co MOF deposition layer loaded on the NiMo electrode is obtained. The method is simple and easy to control, low in preparation cost and good in electrode stability and hydrogen production effect.

The invention relates to the technical field of multifunctional composite materials, in particular to wave-absorbing, photo-thermal and deicing integrated carbon aerogel and a preparation method thereof. The wave-absorbing, photo-thermal and deicing integrated carbon aerogel is characterized by comprising the following raw materials: 5-15 parts of a dominant bio-based material; 3-10 parts of an auxiliary bio-based material; 0.5 to 3 parts of cobalt salt; 1-5 parts of a photo-thermal material, namely an MXene material; a dispersion medium: 40-80 ml of a 1% v / v acetic acid solution; the concentration of the photo-thermal material dispersion liquid is 0.5 mg / mL to 2 mg / mL, and the concentration of the photo-thermal Compared with the prior art, the wave-absorbing, photo-thermal and deicing integrated carbon aerogel and the preparation method thereof have the advantages that through the collaborative design of a bio-based framework and MXene, the problems of function splitting, non-uniform photo-thermal material loading and insufficient wave-absorbing strength of an existing material are solved, collaborative fusion of photo-thermal deicing and wave-absorbing functions is realized, and the wave-absorbing performance of the wave-absorbing, photo-thermal and deicing integrated carbon aerogel is improved. The method is suitable for extreme environment protection scenes such as aerospace and wind power equipment.

The invention belongs to the technical field of air power supplies, and relates to modification treatment of an oxide, in particular to a cerium oxide doped transition metal oxide and a preparation method thereof, an air cathode and an air power supply. The preparation method comprises the following steps: dissolving cerium salt, cobalt salt and manganese salt in water, uniformly mixing to obtain a mixed solution, adjusting the pH value of the mixed solution to 9-11, and carrying out a sedimentation reaction to obtain a sediment; and drying the precipitate, and calcining in an air atmosphere at 300 + / -10 DEG C for 2-4 hours to obtain the cerium oxide doped transition metal oxide. The cerium oxide doped transition metal oxide is cerium doped cobalt manganese oxide with a spinel structure, and the doping amount of cerium is 20 + / -1wt%. The cerium oxide doped transition metal oxide provided by the invention is applied to an air cathode as a catalyst, and has good stability and high catalytic activity. The performance of an air power supply containing the oxide is remarkably improved. The method for preparing the oxide provided by the invention is simple and easy to operate, and is suitable for large-scale production.

The present disclosure relates to the technical field of powder metallurgy, especially to a coarse grain cemented carbide and a preparation method thereof. Pseudo particles in coarse grain tungsten carbide are removed by pretreating process. Broken of the coarse grain tungsten carbide in traditional wet milling is avoid by solid-liquid stirring, spay granulating and surface covering, which also guarantee the uniform distribution of PEG and cobalt salt. Transformation from cobalt salt to cobalt is safely and effectively guaranteed by performing two sintering stages with different atmosphere and temperature to obtain a WC—Co mixture material. By performing spark plasma sintering process, the precipitation of nano fine grain tungsten carbide guarantees regrowth of defect occurred in pretreating process. The coarse grain cemented carbide with the average grain size of WC above 10 μm, the uniform cobalt phase distribution and be bending strength not less than 2200 MPa is prepared.

The invention provides a nitrogen modified iron-cobalt bimetallic catalyst as well as a preparation method and application thereof, and belongs to the technical field of catalysts. The catalyst takes iron and cobalt as active components, and is prepared by adopting a coprecipitation-hydrothermal-step atmosphere heat treatment process: firstly, carrying out coprecipitation reaction on iron salt and cobalt salt, controlling the pH value to be 11 + / -0.5, carrying out aging and hydrothermal treatment, filtering, washing, drying and grinding to obtain a precursor; and calcining the precursor in a hydrogen-containing mixed atmosphere at 400-500 DEG C, and then calcining the precursor in an ammonia-containing mixed atmosphere at 450-600 DEG C to obtain the nitrogen surface modified iron-cobalt bimetallic catalyst. The catalyst is of a carrier-free iron-cobalt bimetallic structure, nitrogen atoms are embedded into alloy lattices or adsorbed on the surface in the form of pyridine nitrogen, pyrrole nitrogen or graphite nitrogen, and a Fe / Co-N high-activity interface is formed.

The invention belongs to the technical field of electro-catalysis water decomposition, and relates to a self-supporting W-NiCoP / NF composite material and a preparation method and application thereof. Cobalt salt, terephthalic acid, acetic acid and foamed nickel are subjected to a first solvothermal reaction, and defect type Co-MOF / NF is obtained; immersing the defect type Co-MOF / NF into a tungstate solution, and then carrying out a second solvothermal reaction to obtain a defect type W-Co-MOF / NF precursor; and carrying out phosphating heat treatment on the defect type W-Co-MOF / NF precursor and a phosphorus source in an inert atmosphere to obtain the W-Co-MOF / NF composite material. According to the preparation method disclosed by the invention, the tungsten-doped nickel-cobalt bimetallic phosphide with rich defect structures is successfully constructed on the foamed nickel substrate through a step-by-step solvothermal and gas-phase phosphating strategy, so that organic combination of a bimetallic synergistic effect and defect engineering is realized; the prepared self-supporting composite material has more active sites, a better electronic structure regulation effect and better stability.

The invention provides a chlorine corrosion resistant cathode for electrolyzing seawater as well as a preparation method and application of the chlorine corrosion resistant cathode. The preparation method comprises the following steps: S1, dissolving a cobalt salt, a nickel salt, a morphology regulating agent and a structure-directing agent in a solvent according to a molar ratio of (1-2.5): (1-2.5): (8-12): (6-10), and stirring to form a first solution; s2, a titanium mesh and the first solution are subjected to a hydrothermal reaction at the temperature of 100-150 DEG C, and CoNi layered double hydroxide with the shape of a nanoneedle array grows on the titanium mesh in situ; s3, selenium powder and a reducing agent are dissolved in a solvent according to the molar ratio of 1: (0.8-1.5) and stirred to form a second solution; and S4, carrying out hydrothermal reaction on the titanium mesh on which the CoNi layered double hydroxides grow in situ and a second solution at 150-190 DEG C so as to grow cobalt-nickel bimetallic selenide of which the morphology is a nanoneedle array in situ on the titanium mesh, thereby obtaining the chlorine corrosion resistant cathode.

The invention discloses a catalytic system for preparing amine compounds through nitro reduction and application of the catalytic system. The catalytic system comprises an alkaline aqueous solution, a reducing agent and a catalyst, the alkaline aqueous solution is an alkali metal hydroxide aqueous solution; the reducing agent is alkali metal hydroboron and / or alkaline earth metal hydroboron; the catalyst is copper salt lewis acid and / or other lewis acid; the other Lewis acid is selected from one or a combination of more of cobalt salt, ferric salt, zinc salt, manganese salt and palladium salt. When the catalytic system is used for reducing the aromatic nitro-compound, the using amount of a reducing agent is small, meanwhile, the using amount of an organic solvent is reduced, the reaction yield is high, the reaction is milder, and amplified production of the process is facilitated.

The invention provides a preparation method of a CoFe alloy fiber microwave absorbent, which comprises the following steps: immersing cotton fibers in an aqueous solution containing ferric salt and cobalt salt for dipping, taking out, and drying to obtain cotton fibers loaded with iron ions and cobalt ions; under the nitrogen atmosphere, the temperature is increased to 600-800 DEG C from the room temperature at the speed of 4 DEG C / min, after constant-temperature roasting, natural cooling is conducted to the room temperature, and the CoFe alloy fiber microwave absorbent is obtained. The invention further provides application of the CoFe alloy fiber microwave absorbent, and the CoFe alloy fiber microwave absorbent is used for preparing stealth materials or / and electromagnetic protection materials. The raw materials are wide in source and low in cost, only an impregnation method and a roasting method are adopted, no organic solvent is used, and the method is green and environmentally friendly; the technological process is simple, easy to operate, low in synthesis cost and suitable for industrial production; the prepared CoFe alloy fiber microwave absorbent is high in magnetism, facilitates double-layer optimization design of microwave absorption performance, and has the advantages of being good in microwave absorption performance and light in weight.

The invention relates to a high-entropy metal oxide catalyst and a preparation method and application thereof.The preparation method comprises the following steps that S1, ferric salt, cobalt salt, manganese salt, nickel salt, copper salt and organic alkaline matter are mixed to obtain a mixed solution, hydrothermal reaction is conducted, and a precursor is obtained; and S2, calcining the precursor at the temperature of 500-600 DEG C to obtain the high-entropy metal oxide catalyst. The high-entropy metal oxide catalyst uniformly doped with iron, cobalt, manganese, nickel and copper is prepared by adopting a hydrothermal reaction and calcination method, and the high-entropy metal oxide catalyst not only can efficiently catalyze ozone to remove antibiotics, but also can still keep an excellent antibiotic removal rate constant in a water body containing hetero ions and humic acid; and the anti-interference capability is excellent.

The invention relates to a zeolite-based cobalt catalyst and a preparation method and application thereof, and belongs to the technical field of advanced oxidation of persulfate. The preparation method comprises the following steps: mixing zeolite and cobalt salt in water for ion exchange, and then filtering and drying to obtain precursor powder; and carrying out ball milling on the precursor powder to obtain the zeolite-based cobalt catalyst, and activating PMS to degrade organic pollutants by using the zeolite-based cobalt catalyst. The zeolite-based cobalt catalyst increases the utilization rate of a metal active center by confining part of metal active sites, creates a nanoscale heterogeneous reaction space, shortens the internal diffusion distance, and realizes a more efficient and faster catalytic oxidation process.

The invention provides a ZIF-67 (at) Co / HPLFM composite material and a preparation method and application of the ZIF-67 (at) Co / HPLFM composite material, and the preparation method comprises the following steps: providing a hollow porous straw lignin fiber membrane (HPLFM); cobalt salt is dissolved in absolute ethyl alcohol, the hollow porous straw lignin fiber membrane is taken and placed in the mixed solution, absolute ethyl alcohol dissolved with 2-methylimidazole is dropwise added into the mixed solution after oscillation, and oscillation continues for a period of time; taking out the hollow porous straw lignin fiber membrane, washing, and freeze-drying to obtain a precursor material; and carrying out high-temperature calcination on the precursor material to obtain the ZIF-67 (at) Co / HPLFM composite material. The high surface activity and the porous hollow structure of the hollow porous straw lignin fiber membrane are utilized, ZIF-67 is loaded on HPLFM, the ZIF-67-coated Co / HPLFM composite material is obtained through further treatment, and the material has high specific surface area and excellent adsorption performance and has good application prospects in organic pollutant degradation by activating peroxymonosulfate.

The invention relates to a RuO2-Co3O4 electro-catalytic material as well as a preparation method and application thereof. The electro-catalytic material comprises a carbon cloth substrate and a nanosheet array growing on the surface of a carbon cloth fiber, the nanosheet comprises a heterostructure which is composed of crystalline state Co3O4 particles and amorphous state RuO2. The preparation method comprises the following steps: taking activated carbon cloth as a working electrode, performing constant-potential electrodeposition in electrolyte containing cobalt salt, and then cleaning and drying to obtain Co (OH) 2 loaded carbon cloth; carrying out heat treatment on the carbon cloth for the first time to obtain carbon cloth loaded with Co3O4 nanosheets; then immersing the carbon cloth into a solution containing ruthenium salt to enable the ruthenium salt to be adsorbed on the Co3O4 nanosheet, and then cleaning and drying to obtain a precursor; and carrying out second heat treatment on the precursor to obtain the RuO2-Co3O4 heterojunction electro-catalytic material. The RuO2-Co3O4 electrocatalyst has the advantages that the RuO2-Co3O4 electrocatalyst has excellent electrocatalytic oxygen evolution activity and long-time operation stability. The preparation process is simple, the thickness of the catalyst layer can be controlled, and the process operation complexity and the requirement on equipment are reduced.

The invention discloses corrosion-resistant aerogel and a processing technology thereof.The processing technology comprises the following steps that graphene oxide dispersion liquid and a metal organic framework precursor ZIF-67 are mixed, metal salt is cobalt salt, the mass ratio of graphene oxide to metal salt is 1: 0.5-1: 2, and homogeneous sol is formed through ultrasonic treatment. After the composite aerogel is soaked in strong acid HCl with the pH value of 1 and strong alkali NaOH with the pH value of 14 for 7 days, the mass loss rate is smaller than 5%, meanwhile, the porosity is kept to be larger than or equal to 95%, the compressive strength is kept to be larger than or equal to 1.5 MPa, and the industrial problems that traditional aerogel collapses in a structure and degrades in performance in a corrosive medium are solved.

The invention discloses a preparation method and application of a high-entropy layered double hydroxide oxygen evolution catalyst, and relates to the field of oxygen evolution reaction catalysis, and the preparation method comprises the following steps: S1, washing foamed nickel in absolute ethyl alcohol and deionized water, and then carrying out ultrasonic treatment in a hydrochloric acid solution to obtain pretreated foamed nickel; s2, adding ferric salt, cobalt salt, nickel salt, manganese salt, zinc salt and a proper amount of urea into deionized water, then adding ammonium fluoride, and uniformly stirring to obtain a mixed solution; and S3, transferring the mixed solution and the pretreated foamed nickel into a reaction kettle, carrying out a hydrothermal reaction, and washing and drying the obtained product to obtain the high-entropy layered double hydroxide oxygen evolution catalyst. According to the method, the key regulation and control effect of NH4F on the structure, chemical and electro-catalytic properties of HELDHs in the synthesis process of the HELDHs is analyzed, and the performance enhancement is attributed to NH4F-induced morphology and crystal engineering and catalytic active cation vacancies generated in situ through selective leaching of Zn < 2 + > and adsorption of sulfate under the alkaline condition.

The application provides a preparation method of a platinum-cobalt alloy catalyst, which comprises the following steps: preparing a hexadecyl trimethyl ammonium bromide clear solution; preparing a platinum compound, a transition metal cobalt salt and a dimethyl imidazole dispersion solution; adding the dispersion solution into the hexadecyl trimethyl ammonium bromide clear solution in sequence, stirring, adding a carbon black, a ketchen black, a cabot black or a carbon nanotube slurry, and continuously stirring to obtain a mixed solution I; then centrifuging, vacuum drying and grinding the mixed solution I to obtain an intermediate powder; then performing a different temperature staged calcination on the intermediate powder under a reducing / inert atmosphere to obtain an ordered low platinum-cobalt alloy catalyst powder; and then performing an acid washing, suction filtration, vacuum drying and grinding on the ordered low platinum-cobalt alloy catalyst powder to obtain a catalyst product which can be used in a fuel cell. The platinum-cobalt alloy catalyst prepared by the application can be applied to a proton exchange membrane fuel cell as a cathode oxygen reduction catalyst, and the platinum-cobalt alloy catalyst can improve the utilization rate, catalytic activity and durability of the noble metal Pt in the fuel cell cathode ORR catalyst, and can reduce the manufacturing cost and use cost of the fuel cell.

The invention discloses a preparation method and application of a FeCo-MOF derived CoFe2O4 / biochar composite material, and belongs to the technical field of antibiotic wastewater treatment. The method comprises the following steps: (1) dissolving terephthalic acid in DMF (Dimethyl Formamide) to form a solution A, dissolving ferric salt and cobalt salt in DMF to form a solution B, mixing the two solutions, reacting, centrifuging, washing, drying and grinding to obtain a FeCo-MOF material; and (2) mixing the FeCo-MOF material with peanut shells, grinding, calcining the obtained mixed powder in an N2 atmosphere, and then grinding to obtain the FeCo-MOF derived CoFe2O4 / biochar composite material. When the prepared composite material is used as a catalyst to degrade OFL in a PMS system, the degradation efficiency reaches 79.78%-89.89%, and the degradation rate constant reaches 0.094 min <-1 >-0.139 min <-1 >.

The application belongs to the technical field of lithium ion batteries, and particularly relates to a kind of one-dimensional LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 ternary layered oxide positive electrode material and a preparation method thereof, which comprises the following steps: adding a nickel salt, a cobalt salt and a manganese salt into water, stirring and dissolving to obtain a solution A; adding LiMn2O4 into the solution A and stirring uniformly to obtain a solution B; mixing a lithium salt with water to obtain a solution C, and under stirring, adding the solution C into the solution B to obtain a solution D; evaporating the solution D under stirring to obtain a precursor powder; and sintering the precursor powder at 400-600 DEG C, and then sintering at 750-850 DEG C to obtain the positive electrode material. 1 / 3 Co 1 / 3 Mn 1 / 3 O2 material.

The invention discloses a nickel-cobalt layered double hydroxide for a supercapacitor and a preparation method and application thereof, and belongs to the technical field of energy storage. The preparation method of the nickel-cobalt layered double hydroxide for the supercapacitor comprises the following steps: performing hydrothermal reaction on nickel salt, cobalt salt, ammonium citrate and urea to obtain the nickel-cobalt layered double hydroxide, the temperature of the hydrothermal reaction is 120-150 DEG C, and the time of the hydrothermal reaction is 6-12 hours. According to the invention, ammonium citrate is added to regulate the precipitation rate of the precursor, so that the morphology of the nickel-cobalt layered double hydroxide can be regulated and controlled, and the situation that the nickel-cobalt layered double hydroxide is rapidly combined with hydroxyl ions to cause too fast crystallization and coarse crystal grains is avoided; and meanwhile, the concentration uniformity of metal ions in the solution is regulated and controlled, so that the crystallinity of the nickel-cobalt layered double hydroxide is uniform, and lattice defects are reduced. Therefore, when the material is used as an electrode material of a supercapacitor, the material has relatively high specific discharge capacity.

The application provides a porous carbon nanofiber electrocatalyst loaded with cobalt / lanthanum hydroxide heterojunction and a preparation method. The preparation method comprises the following steps: adding 4,4-diamino diphenyl ether and pyromellitic dianhydride into a solvent, uniformly mixing, and preparing a polyamide acid precursor spinning solution; electrospinning the prepared polyamide acid precursor spinning solution to prepare polyamide acid nanofibers; immersing the prepared polyamide acid nanofibers in a mixed metal salt solution containing cobalt salt, lanthanum salt and zinc salt to prepare polyamide acid nanofiber precursors loaded with metal ions; and performing programmed temperature heat treatment on the prepared polyamide acid nanofiber precursors loaded with metal ions in a protective atmosphere to prepare the porous carbon nanofiber electrocatalyst loaded with cobalt / lanthanum hydroxide heterojunction. The prepared porous carbon nanofiber electrocatalyst loaded with cobalt / lanthanum hydroxide heterojunction has excellent electrochemical oxygen reduction reaction and oxygen evolution reaction bifunctional catalytic activity.

The application discloses a preparation method of a bimetallic catalyst. A polymer containing a large amount of carboxyl groups is used as a ligand polymer to perform a coordination reaction with a zinc salt and a cobalt salt, so as to prepare a high-efficiency bimetallic catalyst. When the bimetallic catalyst synthesized by the application is used to prepare polyether polyols, the catalyst can be used in an alkaline environment and an environment with metal ions within 20 ppm. The catalyst provides convenience for switching from an alkali catalytic system to a bimetallic catalytic system, greatly simplifies the washing tank condition, and greatly reduces the switching cost of a polyether production system. The application has simple process, easily-obtained raw materials and easy industrial production.

The invention belongs to the technical field of electrode materials, and particularly relates to a MnCo2O4 / ZnCo2O4 nano composite material as well as a preparation method and application thereof. The preparation method comprises the following steps: taking soluble manganese salt and soluble cobalt salt as raw materials, taking foamed nickel as a carrier, carrying out hydrothermal reaction in an alkaline environment to obtain MnCo-LDH / NF, then immersing the MnCo-LDH / NF in a precursor solution composed of the soluble cobalt salt, soluble zinc salt and 2-methylimidazole, carrying out coordination reaction to obtain MnCo-LDH ZIF-67 / ZIF-8, and finally carrying out heat treatment to obtain the MnCo2O4 / ZnCo2O4 nano composite material. In the MnCo2O4 / ZnCo2O4 nano composite material obtained by the method disclosed by the invention, MnCo2O4 with a nanorod structure and ZnCo2O4 with a dodecahedron structure form a heterojunction, so that the defect of poor conductivity of MnCo2O4 is overcome.

The invention relates to the technical field of denitration catalysts, and discloses a composite oxide catalyst and a preparation method thereof. The preparation method of the composite oxide catalyst comprises the following steps: mixing a manganese salt, a cobalt salt and deionized water, and carrying out a first precipitation reaction to obtain a first mixture; cerium salt and the first mixture are mixed and subjected to a second precipitation reaction, and a second mixture is obtained; sequentially drying and sintering the second mixture to obtain a composite oxide catalyst; wherein the molar ratio of the manganese element in the manganese salt to the cobalt element in the cobalt salt is (1.5-3): 1, preferably (1.9-2.1): 1. The preparation process of the composite oxide catalyst is simple, raw material loss is not caused, and the composite oxide catalyst prepared by the method has excellent denitration performance under a low-temperature condition.

The invention discloses a titanium dioxide nanorod / dissimilar metal MOFs heterojunction material and a preparation method and application thereof, and belongs to the technical field of photoelectrochemistry seawater hydrogen production. Soluble nickel salt, soluble cadmium salt or soluble cobalt salt and ammonium molybdate are adopted as metal sources, spherical dissimilar metal MOFs grow on the surface of a TiO2 nanorod in situ, and the TiO2 nanorod / dissimilar metal MOFs heterojunction material is prepared. According to the present invention, the oxygen deficiency-regulated dissimilar metal MOFs material (i.e., the titanium dioxide nanorod / dissimilar metal MOFs heterojunction material) is obtained through subsequent acid etching and annealing treatment, the material is subjected to in-situ reconstruction during the OER process to spontaneously form the active hydroxide (NiOOH) of anion protection (MoO4 < 2->), and the excellent stability is represented; only small Faraday efficiency loss (1.2-2.3%) occurs in a high chloride ion environment (3.5 wt%-7wt% of NaCl), and an extensible path is provided for industrial-scale solar hydrogen production by using seawater.

The application belongs to the technical field of inorganic nanometer material preparation, and particularly relates to a hollow manganese dioxide / cobalt manganate loaded nitrogen-doped carbon hybrid material and a preparation method thereof. The steps of the application are as follows: S1, dispersing manganese source material in N,N-dimethylformamide to form a uniform solution; S2, adding an organic ligand to the solution obtained in step S1 and continuously stirring to obtain a mixed solution, and then transferring the mixed solution to a reaction kettle for a solvothermal reaction; S3, sequentially washing and drying the product obtained through the solvothermal reaction, and then grinding the product and a cobalt salt to form a mixture powder; and S4, performing a high-temperature pyrolysis reaction on the mixture powder, and obtaining the hollow manganese dioxide / cobalt manganate loaded nitrogen-doped carbon hybrid material rich in mesopores and macropores after the reaction stops. The application has a large specific surface area and a multi-pore structure, slows down the migration and aggregation of metal particles and the loss of pyrolysis intermediates in the heat treatment process, and improves the electrochemical activity and stability of the transition metal / nitrogen-doped carbon electrocatalyst.