278 results about "Surface oxygen" patented technology

The invention provides an in-situ modified lithium-rich manganese-based precursor and a preparation method and application thereof.The preparation method comprises the following steps that a nickel-cobalt-manganese mixed metal salt solution, a precipitator solution and a complexing agent solution are introduced into a base solution for a first coprecipitation reaction, and after the first coprecipitation reaction is finished, feeding is stopped; and introducing a doped nickel-cobalt-manganese mixed metal salt solution, a precipitant solution, a complexing agent solution and a carbon source solution into a system after the first coprecipitation reaction is finished, and carrying out a second coprecipitation reaction to obtain the in-situ modified lithium-rich manganese-based precursor. According to the preparation method, doping elements and a carbon source are introduced when the lithium-rich manganese-based precursor is prepared through the coprecipitation reaction, in-situ uniform construction of oxygen vacancies and a carbon coating layer on the surface of the material is synchronously achieved, the in-situ modified lithium-rich manganese-based precursor is obtained, the treatment step of subsequent secondary coating can be reduced, the production cost can be reduced, and the method is suitable for industrial production. The technological process is shortened.

The invention provides a Cu2O-based heterogeneous composite material as well as a preparation method and application thereof. The preparation method comprises the following steps: coating the surface of a Cu2O hollow sphere substrate with a carbon layer, and depositing layered double hydroxides (LDHs) and metal palladium (Pd) nanoparticles on the carbon layer. According to the material, through a Cu2O-carbon layer-LDHs-Pd multistage heterostructure design, space optimization of light absorption, charge transfer and catalytic sites is realized; cu2O-carbon layer-LDHs interface coupling promotes directed migration of photo-induced electron-hole pairs, and the surface plasmon resonance effect of Pd nanoparticles enhances the charge separation efficiency; the LDHs optimizes a charge transfer path through surface oxygen vacancy or metal valence cycle, so that synergistic oxidation of non-free radicals and free radicals is realized, the organic matter degradation efficiency is remarkably improved, the oxidation path is widened, and the performance bottleneck of a single material is broken through.

The invention discloses a preparation method of a low-temperature high-air-velocity VOC (volatile organic compound) catalyst and the catalyst, belongs to the field of industrial waste gas treatment, and aims to solve the problems that volatile organic compounds VOCs as main atmospheric pollutants cause photochemical smoke and harm human health; a VOCs catalyst in the prior art cannot meet catalytic combustion treatment process conditions at a high space velocity of 30000 h <-1 >. The high airspeed VOCs noble metal catalyst is developed aiming at a complex volatile organic compound VOCs catalytic combustion technology and meets industrial requirements, and the maximum airspeed of the catalyst is 30000 h <-1 >. The catalyst is an integral honeycomb catalyst formed by taking a double-effect synergistic two-component noble metal precursor, a transition metal oxide and a rare earth oxide as active components, so that the oxygen vacancy of a carrier and the acidity of a catalyst Bronsted acid are enhanced, and the capabilities of oxygen vacancy flow on the surface of the catalyst and adsorption and oxidative dissociation of functional groups on the surface of VOCs (Volatile Organic Compounds) are enhanced.

The invention belongs to the technical field of pyrolytic carbon black quality detection methods, and particularly relates to a method for determining the specific surface area of carbon black. The method for measuring the specific surface area of the carbon black comprises the following steps: firstly, adding an additive into the carbon black, stirring, centrifuging and filtering; the auxiliary agent is prepared by compounding polyacrylamide, dipolyglycerol dioleate and water; adding water for cleaning, centrifuging, filtering and drying; and finally calculating the specific surface area of the carbon black through a gas adsorption method. According to the method, the carbon black is pretreated, so that the influence of surface oxygen-containing functional groups, aromatic ring impurities and the like on nitrogen adsorption is effectively eliminated, and the problem that the pore structure of the carbon black is damaged by high-temperature degassing in a traditional method is solved through proper microwave irradiation, so that the measured specific surface area result is closer to a true value; methodologies such as precision and repeatability are more stable.

The invention provides a method for preparing a spinel type catalyst rich in oxygen vacancies under the assistance of magnetization treatment and application of the spinel type catalyst. The synthesis method of the catalyst comprises the following steps: (1) preparing a precursor of the catalyst by adopting a hydrothermal method: putting a metal foam carrier into a mixed solution of metal salt ions such as ferric nitrate, manganous nitrate and cobalt nitrate, adding ammonium fluoride and urea, carrying out hydrothermal reaction, repeating the hydrothermal reaction for several times, and washing and drying to obtain the precursor; and (2) putting the catalyst precursor into a magnetization reactor, putting the magnetization reactor in the center of an alternating magnetic field coil, and carrying out magnetization treatment on the catalyst precursor in an air or oxygen atmosphere to obtain the spinel type catalyst rich in oxygen vacancies. The method is simple in process and low in cost, and the obtained product is uniform in morphology and good in repeatability and has high photo-thermal catalytic oxidation toluene performance. Through a clean, pollution-free and in-situ directional heating electromagnetic induction auxiliary technology, removal of oxygen atoms on the surface of the spinel catalyst is promoted, so that rich oxygen vacancies are introduced into cobalt-manganese spinel, the exchange effect between the catalyst and oxygen molecules is accelerated, and the reaction rate of catalytic oxidation of VOCs is promoted. When the intensity of simulated sunlight is 500 cm <-2 >, the concentration of toluene is 1000 ppm, the air speed is 45000 mL.gcat <-1 >. H <-1 >, the conversion rate of toluene reaches 86% or above, and high-efficiency oxidation of toluene can be realized under the driving of the simulated sunlight.

The invention discloses a preparation method of a lithium cobalt oxide material, the lithium cobalt oxide material and a secondary battery, and belongs to the field of positive electrode materials. The lithium cobalt oxide material which is stable in surface structure and good in cycle performance is prepared through acid leaching, phosphate primary coating and fluorine acid ammonium salt secondary coating of lithium cobalt oxide in sequence. The lithium cobalt oxide reacts with H < + > in the acid solution in the acid leaching process, and active sites are formed on the surface of the lithium cobalt oxide; pO4 < 3-> in the phosphate reacts with active sites in the subsequent primary coating process to form stably combined primary coated lithium cobalt oxide, and the phosphate is distributed on the surface of the lithium cobalt oxide in a dotted manner, so that the corrosion of an electrolyte can be inhibited; in the secondary coating process, NH4 < + > in the ammonium fluoride salt is combined with surface O < 2-> of an uncoated area on the surface of the primary coated lithium cobalt oxide to generate water and ammonia gas, so that a tightly coated fluoride coating layer is formed, and the fluoride coating layer can effectively reduce corrosion of hydrofluoric acid generated by electrolyte decomposition to the positive electrode material, reduce release of oxygen on the surface layer and improve the service life of the positive electrode material. The surface structure of the lithium cobalt oxide material is further stabilized.

According to the preparation method and the application of the high-nickel positive electrode material with the core-shell structure, the deep charge-discharge specific capacity and the cycling stability of the layered positive electrode material are remarkably improved by controlling the calcination condition of the high-nickel positive electrode material in an oxygen-free environment, regulating and controlling the oxygen vacancy on the surface of the material and synthesizing the sample with the core-shell structure. Meanwhile, the method is simple, effective and low in cost, and the prepared material is good in morphology uniformity and suitable for large-scale production.

The present invention belongs to the technical field of battery materials, and provides a lithium-rich lithium ferrite lithium supplementing agent, a synthesis method and a use thereof. In the synthesis method, a solid electrolyte, conductive carbon and elemental sulfur are mixed and subjected to low-temperature heat treatment to form a composite mixture, and then the composite mixture is secondarily mixed with lithium-rich lithium ferrite and subjected to low-temperature heat treatment to form a mixed coating layer on the lithium-rich lithium ferrite, thereby obtaining the lithium-rich lithium ferrite lithium supplementing agent. Sulfur in the mixed coating layer can absorb the surface oxygen released during the charging process of the lithium-rich lithium ferrite, thereby reducing gas generation. The solid electrolyte and the conductive carbon can form an ionic and electronic conductive network, avoiding the difficulty of Li+ extraction and the decrease of lithium supplementing capacity caused by too thick sulfur coating. At the same time, the low-temperature heat treatment causes the elemental sulfur to melt, which can play a role in dispersion and adhesion, realizing the uniform dispersion of the solid electrolyte and the conductive carbon and the effective coating of the composite mixture, which is beneficial to improving the binding property and compatibility. The obtained mixed coating layer can effectively improve the air stability of the lithium supplementing agent.

The invention discloses a positive electrode material, a surface layer reconstruction material and a lithium ion battery, in an XPS spectrogram of the positive electrode material, after a surface oxygen element O1s characteristic peak of the positive electrode material is subjected to peak division treatment, at least two characteristic peaks can be obtained, including a first characteristic peak in a range of 529.0 + / -0.5 eV and a second characteristic peak in a range of 531.2 + / -0.5 eV; the positive electrode material meets at least one of the following conditions: (1) the separation degree of the first characteristic peak and the second characteristic peak is less than or equal to 1.0; and (2) the peak position distance between the first characteristic peak and the second characteristic peak is less than or equal to 2.4 eV. The positive electrode material disclosed by the embodiment of the invention has a more stable structure, so that the cycle life of the battery is prolonged, and the performance of the battery in the aspects of safety and the like is improved.

The invention relates to the technical field of heat storage materials, in particular to a simulation method for strengthening the heat storage performance of molten salt by using nano-particle oxygen vacancy defects. The method comprises the following steps: constructing a unit cell structure of silicon dioxide, determining a nanoparticle model containing a surface oxygen vacancy defect based on the unit cell structure of silicon dioxide, and constructing a final silicon dioxide-potassium carbonate nanofluid model based on the nanoparticle model containing the surface oxygen vacancy defect; performing molecular dynamics simulation based on the final silicon dioxide-potassium carbonate nanofluid model to obtain molecular dynamics simulation data; based on molecular dynamics simulation data, the final heat storage performance parameters of the silicon dioxide-potassium carbonate nanofluid model are determined, and by means of the setting mode, results obtained through simulation discover that the heat storage performance of the molten salt can be effectively improved through nano-particle oxygen vacancy defects.

The invention aims to solve the problems of poor activity and easy sintering of a copper-zinc catalyst in a reaction for synthesizing methanol through CO2 hydrogenation in the prior art, and provides a high-activity and stable copper-zinc catalyst for synthesizing methanol through CO2 hydrogenation and a preparation method of the high-activity and stable copper-zinc catalyst. The prepared modified copper-zinc catalyst is prepared by taking copper salt, zinc salt and a precipitant as raw materials, firstly preparing the copper-zinc catalyst through a coprecipitation method, then modifying the copper-zinc catalyst by taking a hydroxyl-rich carbon-containing compound as a carbon source and zirconium salt, and carbonizing. Compared with a copper-zinc catalyst prepared by a traditional coprecipitation method, the modified copper-zinc catalyst prepared by the preparation method disclosed by the invention can anchor zirconium nanoparticles by utilizing a surface hydrophobic carbon layer formed by carbonizing the hydroxyl-rich carbon-containing compound, so that the agglomeration of catalyst particles can be avoided, and more surface oxygen defects beneficial to catalysis are provided; furthermore, the catalytic reaction activity and stability can be improved.

The invention relates to the technical field of sodium ion batteries, in particular to an MOF-coated layered oxide positive electrode material, a preparation method thereof and a sodium ion battery. The preparation method comprises the following steps: ball-milling and mixing a metal source and a sodium source, and calcining to obtain a layered oxide positive electrode material; the preparation method comprises the following steps: adding Mn salt or Al salt and 2, 5-dihydroxy terephthalic acid into a mixed solvent composed of dimethyl amide, ethanol and deionized water, stirring, and reacting to obtain an MOF material; and mixing the layered oxide positive electrode material and the MOF material, and carrying out heat treatment to obtain the MOF-coated layered oxide positive electrode material. The MOF serving as a coating layer material has a large-aperture structure, a diffusion channel is provided for sodium ion transmission, and the migration rate of sodium ions is increased; mn-MOF or Al-MOF is used as a coating layer material, so that the surface oxygen defect concentration of the layered oxide positive electrode material can be adjusted, the reversibility of oxidation reduction of oxygen anions can be improved, and the coulombic efficiency and the cycling stability of the battery during charging and discharging under a high-voltage condition can be further improved.

The invention discloses a sodium metavanadate-based catalyst activity gradient regulation and regeneration system and method, and relates to the technical field of industrial catalyst regeneration, the sodium metavanadate-based catalyst is of a unique layered structure, the sodium metavanadate-based catalyst comprises an outer layer, a middle layer and an inner layer from the surface to the interior in sequence, and active components and doping elements of all the layers are different; the outer layer is doped with high-content sodium metavanadate and manganese oxide, reactant molecules can be quickly adsorbed and activated in the initial stage of the reaction, the manganese oxide can provide additional active sites, reduce reaction activation energy and promote quick start of the reaction, and the middle layer is doped with a proper amount of sodium metavanadate and cerium oxide, so that the reaction is more stable in the process of the reaction. The cerium oxide can adjust migration and conversion of oxygen species on the surface of the catalyst, optimize the reaction path, improve the selectivity of a target product and reduce side reactions, the inner layer is doped with the low-content sodium metavanadate and tungsten oxide, and the structural stability of the catalyst under high-temperature and long-time reaction is maintained by means of the high stability of the tungsten oxide.

The invention discloses a preparation method of a hard carbon sodium battery negative electrode material, and relates to a preparation method of a negative electrode material. The method comprises the following steps: 1, pre-oxidation treatment; 2, preparing an asphalt / binder mixture; 3, heat treatment; 4, rough grinding; 5, carbonizing; and 6, crushing. Asphalt which is low in cost and stable in supply is used as a raw material, surface oxygen-containing functional groups are enhanced through surface oxidation, then resin is added to serve as a binder to enable the asphalt to form a cross-linked structure, a large number of irregular closed-pore structures exist in a generated hard carbon structure through high-temperature carbonization, the sodium storage performance of the material is improved, meanwhile, the specific surface area is reduced, and the specific surface area is increased. Therefore, side reactions are reduced, the first efficiency is improved, and the high-performance sodium battery negative electrode material with the reversible capacity higher than 300mAh / g and the first efficiency higher than 90% is obtained. The hard carbon sodium battery negative electrode material can be obtained.

Partially oxidized carbonaceous materials characterized by substantially homogenous, partially oxygenated surfaces thereof are enabled via microwave-assisted methods that are simple and fast. The exemplary methods include combining carbonaceous material(s), at least one mild oxidizer, at least one nucleophile, and an aqueous solvent system to obtain a mixture; and exposing the mixture to microwave radiation for a predetermined time to produce partially oxidized carbonaceous materials. The predetermined time may be in a range from about 5 seconds to about 2 hours, and the power of the microwave energy may be in a range from about 100 w to about 1700 W. The partially oxidized carbonaceous materials are characterized by a homogeneous distribution of oxygen content in surfaces thereof, in nonzero amounts up to about 10 at %, and a standard deviation of surface oxygen content in a range from about 0.1 at % to about 1.0 at %.

The present invention relates to a method for characterizing oxygen species adsorbed by an ethylene epoxidation catalyst, and to the technical field of catalyst characterization and detection. The method for characterizing oxygen species adsorbed by an ethylene epoxidation catalyst comprises the following steps: pretreating the ethylene epoxidation catalyst with a mixed gas of ethylene / oxygen / helium; adsorbing oxygen on the pretreated ethylene epoxidation catalyst with oxygen, etc. The present invention effectively removes incompletely decomposed Ag precursors by adopting an in-situ reaction induction method in the pretreatment stage of the catalyst. Subsequently, an oxygen adsorption experiment is performed on the Ag catalyst pretreated in situ, and oxygen and other gas phase products generated by programmed temperature desorption are detected by mass spectrometry to detect the composition and characteristics of the ethylene epoxidation catalyst, thereby reducing the interference of Ag precursor salts without increasing the reaction temperature, thereby accurately judging the oxygen active species on the surface of the Ag catalyst.

The invention discloses a preparation method of a full-spectrum response plasmon photocatalyst for reducing carbon dioxide to prepare methane, and belongs to the technical field of photocatalytic reduction of CO2. Tungsten hexacarbonyl and silver nitrate, nickel chloride or chloroauric acid are used as raw materials, and a solvothermal reaction is performed to obtain a plasmon W18O49 nanowire photocatalyst doped with different metal ions. According to the preparation method for preparing the CH4 plasmon photocatalyst through full-spectrum response CO2 reduction, the prepared Au, Ag or N metal ion doped plasmon W18O49 nanowires have high ultraviolet-visible-near infrared light absorption capacity and rich surface oxygen vacancy concentration, adsorption and activation of CO2 molecules are facilitated, meanwhile, the surface oxygen vacancy concentration is increased, and meanwhile, the surface oxygen vacancy concentration is increased. The surface of the catalyst can effectively stabilize a * CO intermediate generated in the photocatalytic CO2 reduction process, and the performance and selectivity of the original plasmon W18O49 for preparing CH4 through photocatalytic CO2 reduction are remarkably improved.

The invention discloses a hydrogen peroxide catalytic reactor for an ultrapure water production system, the ultrapure water production system and a method for continuously producing ultrapure water. A central water distributor in the hydrogen peroxide catalytic reactor is filled with a hydrogen peroxide decomposition catalyst, hollow fiber membranes are arranged around the central water distributor, nitrogen is introduced into the upper ends of the hollow fiber membranes during continuous operation, and the lower ends of the hollow fiber membranes are connected into a vacuum source. The water distributor is divided into three sections by arranging the baffles, the water distributor sequentially passes through the water distributor from bottom to top during operation, hydrogen peroxide carried in pure water to be treated is decomposed into water and oxygen under the action of a catalyst, and dissolved oxygen also enters the hollow fiber membrane to be removed. The problem that the catalytic activity is reduced due to excessive enrichment and oxidation of oxygen on the surface of the hydrogen peroxide decomposition catalyst is effectively avoided, and long-time online operation can be realized without increasing the filling amount of the catalyst.

This porous carbon material has, in a pore size distribution measured by mercury porosimetry, a first peak positioned in a pore diameter range from equal to or greater than 3 nm to less than 10 nm and a second peak positioned in a pore diameter range from equal to or greater than 10 nm to equal to or less than 1 µm, and satisfies at least one of the following (A), (B), and (C).　(A) The X-ray diffraction pattern has a peak (i) that has a half-value width of 0.6° or less and a peak top in the range of 2θ = 25° to 27°.　(B) In measurement of the nitrogen adsorption, the amount of nitrogen adsorption when the relative pressure is 0.2 is 10 cm3 / g to 250 cm3 / g.　(C) The surface oxygen concentration measured by XPS is not more than 6 at%.

The invention discloses a preparation method of an iron-based cocatalyst modified bismuth vanadate photo-anode, which belongs to a photo-anode preparation technology and comprises the following steps: firstly, introducing oxygen vacancies to the surface of BiVO4 through chemical reduction by using a mild reducing agent sodium sulfite (Na2SO3) under a low-temperature condition by a simple chemical reduction method; the introduction of oxygen vacancies improves the charge transfer efficiency and the carrier separation efficiency. And then loading the NiFeOX nano thin layer on the surface of BiVO4, and optimizing the loading capacity of the cocatalyst by adjusting the reaction time. BiVO4 is cooperatively modified through oxygen vacancies and a cocatalyst NiFeOX. And a feasible strategy is provided for simply designing and preparing a high-performance and high-durability BiVO4-based photo-anode material.

The invention belongs to the technical field of wire grinding, and particularly relates to a bare copper wire surface deoxidizing device and a using method thereof.The bare copper wire surface deoxidizing device comprises a grinding base and a control box installed at the top of the grinding base and further comprises a mounting plate, the mounting plate is fixedly installed on the side wall of the grinding base, and a plurality of oxidation detection units are inserted into the side wall of the mounting plate; each oxidation detection unit is used for detecting the surface roughness of the bare copper wire, the multiple insulation sleeves are fixedly inserted into the side wall of the polishing base, and a detachable mounting pipe is rotationally connected to the interior of each insulation sleeve. According to the device, the oxidation state and degree of the surfaces of the multiple bare copper wires can be monitored online in real time, the grinding time is automatically controlled based on the detection result, grinding piece abrasion is reduced, resource waste is reduced, the grinding efficiency is improved, meanwhile, grinding scraps can be rapidly collected, replacement of a loss piece is reminded in time, and the oxygen removal effect of the bare copper wires is prevented from being affected.

The invention belongs to the technical field of catalysts, and relates to a cerium oxide supported nickel catalyst and a preparation method and application thereof, and the catalyst is composed of a metal nickel active component and a cerium oxide carrier. The cerium oxide prepared by adopting a reversed-phase microemulsion method is dispersed in a nano-scale manner, has a large specific surface area and abundant oxygen vacancies on the surface, can realize high dispersion of metal nickel after loading nickel on the cerium oxide, has relatively high stability, and is beneficial to realizing efficient methanation of carbon dioxide hydrogenation. By changing the preparation conditions of the reversed-phase microemulsion, the number of oxygen vacancies on the surface of the catalyst can be effectively adjusted, and the CO2 hydrogenation reaction performance of the catalyst is regulated and controlled. The cerium oxide supported nickel catalyst prepared by the invention has the CO2 conversion rate of 83% and the CH4 selectivity of 97%, and shows excellent CO2 conversion rate and methane selectivity, which indicates that the cerium oxide-containing catalyst provided by the invention has excellent CO2 hydrogenation performance, shows excellent catalytic activity, product selectivity and stability, and can be used for preparing a catalyst for hydrogenation of CO2. And large-scale industrial application can be realized.

The invention provides an aromatic hydrocarbon chemical synthesis process, which is characterized by comprising the following steps: mixing a certain amount of CO into a mixed gas of H2 and CO2 in a volume ratio of 1: (2-5) to serve as a reaction raw material gas, and reacting at the temperature of 60-80 DEG C under the action of a specific metal oxide and molecular sieve composite catalyst, controlling the feeding space velocity of the reaction raw materials to be 500-2400 mL / h.gcat, the reaction temperature to be 300-550 DEG C and the reaction pressure to be 2-6 Mpa, and carrying out catalytic conversion to obtain an aromatic chemical; according to the method, a certain amount of CO is doped into reaction raw material gas, and a specific metal oxide and molecular sieve composite catalyst is selected to catalyze conversion of H2 and CO2 into aromatic chemicals; compared with the reaction atmosphere of pure H2 and CO2, the doping of CO greatly enhances the concentration of oxygen vacancies on the surface of the metal oxide, so that the ability of the metal oxide to catalyze CO2 to hydrogen-containing C1 species is greatly enhanced, the catalytic conversion rate of CO2 is improved, and the selectivity of aromatic chemicals is finally improved.

The application discloses a preparation method and application of PTFE catalytic filter material, and the preparation of the PTFE catalytic filter material comprises MnCeTi catalyst preparation, PTFE catalytic fiber preparation, heteropoly acid functionalization and needling. The three-dimensional flower-shaped spherical structure of the prepared PTFE catalytic filter material is used to optimize the mass transfer and conversion channel of pollutants, the intermetallic interaction of Mn, Ce and Ti is used to regulate the surface acid sites and active sites of the catalyst, the surface oxygen vacancies, acid sites and other characteristics are further optimized through the heteropoly acid functionalization, and the low-temperature catalytic dioxin performance of the PTFE catalytic filter material is effectively improved. Meanwhile, the heteropoly acid can form polyoxometalate on the surface of the catalyst, the adhesion strength of the catalyst and the filter material is strengthened, the loss problem of the catalyst in the use process is effectively relieved, and the prepared PTFE catalytic filter material has high efficiency and long-term use performance.

The invention provides a silicon-based negative electrode material and a preparation method and application thereof, and particularly relates to the field of negative electrode materials, the negative electrode material comprises an inner core and a coating layer coating the surface of the inner core, the inner core is composed of a porous carbon matrix and silicon nano-particles deposited in pore channels of the porous carbon matrix, the coating layer is a short-range ordered high-texture carbon layer, and the coating layer is a silicon nano-particle coating layer. The thickness of the high-texture carbon layer is 0.5-30 nm, the length-diameter ratio of the carbon lines is 1-10, and the interlayer spacing is 0.33-0.37 nm. According to the technical scheme, through the synergistic effect of the surface oxygen passivation layer and the high-texture carbon coating layer formed at a high temperature, silicon volume expansion is effectively inhibited, side reactions are reduced, and meanwhile the electrode conductivity and cycling stability are remarkably improved.

The invention relates to the technical field of lithium ion batteries, in particular to a nickel cobalt lithium manganate positive electrode material and a preparation method thereof. According to the invention, the technical problems of poor cycle performance and low specific capacity of the existing nickel cobalt lithium manganate positive electrode material are solved. The preparation method comprises the following steps: synthesizing precursor powder by adopting a coprecipitation process; then carrying out high-shear mixing on the precursor, lithium hydroxide, nano niobium oxide and magnesium fluoride; after the mixed material is subjected to pre-oxidation and high-temperature oxygen-enriched gradient sintering, a gradient reduction etching process is adopted in the cooling stage, and strong wind quenching is matched for surface shaping; and finally, carrying out air jet pulverization and demagnetization to obtain the nickel cobalt lithium manganate positive electrode material. According to the method, lattice respiration stress is effectively dissipated by constructing a radial ordered structure, a bulk phase structure is stabilized through multi-element synergistic doping, interfacial ion transport kinetics is optimized through reduction-induced surface oxygen vacancies and a lattice distortion layer, and the synergistic strategy ensures high stability of the material structure and meanwhile, the material structure has a good application prospect. And the de-intercalation efficiency of the active lithium is greatly improved.

The invention discloses high-purity nickel powder prepared from plant polyphenol through field flow control, a system and a method, a sulfonated tannic acid-gallic acid bio-based system is used as a reduction-stabilizer, and green and efficient preparation of nickel nano powder is realized through a multi-physical field synergistic effect of a three-stage gradient continuous flow reactor and double-frequency ultrasonic-pulse microwave-nitrogen bubbling. The total residence time of the reaction is 25.1-37.7 min, mother liquor is reused after being subjected to salt separation treatment (nanofiltration desalination of a NiSO4 system and ion exchange Cl removal of a NiCl2 system), and the wastewater discharge amount is greatly reduced compared with that of a traditional process; the surface oxygen content of the product is smaller than or equal to 0.9 wt%, the PDI is smaller than or equal to 0.15, the tap density is larger than or equal to 4.0 g / cm < 3 >, the GB / T 33828-2017 standard is met, the method can be used for the high-end field of lithium ion batteries and the like, and green industrial production of the nanometer nickel powder is achieved from the source.

This invention discloses a copper-tungsten oxide / zinc oxide heterojunction photocatalyst, its preparation method, and its application, belonging to the field of nanomaterials and photocatalysis technology. Firstly, a single-atom copper-modified plasma W-type photocatalyst is synthesized using a solution-thermal method combined with an impregnation-thermal reduction process. 18 O 49 Nanowires were first prepared; then porous ZnO nanosheets were prepared via a hydrothermal method combined with calcination; finally, single-atom copper-modified plasma W was constructed via electrostatic self-assembly. 18 O 49 Nanowire / porous ZnO nanosheet heterojunction composite material. This invention utilizes the above-described preparation method to prepare Cu-W nanowires with matched band structures. 18 O 49 / ZnO heterojunction can realize the photogenerated electrons of ZnO into the plasma Cu-W 18 O 49 Nanowire implantation stabilizes and increases the surface oxygen vacancy concentration and free electron density, thereby enhancing the surface plasmon resonance effect and promoting the continuous generation of high-energy hot electrons. Single-atom copper active sites and W 18 O 49 The synergistic effect of nanowires enables the enriched hot carriers to efficiently and selectively photocatalytically reduce CO2 to CH4.

An electrode which includes nanoparticles of a carbon-doped tin oxide of formula C—SnO2-x where x=is from 0.001 to 0.1, having surface oxygen vacancies. The electrode includes a fluorine-doped tin oxide substrate. A film of the nanoparticles is present on at least one surface of the fluorine-doped tin oxide substrate. The surface oxygen vacancies correspond to an O 1s peak shift of 0.5-2 eV in the X-ray photoelectron spectroscopy (XPS) for C—SnO2-x compared to C—SnO2 without surface oxygen vacancies.

The invention discloses a sodium ion battery hard carbon negative electrode material and a preparation method thereof, and belongs to the technical field of carbon material synthesis and electrochemistry. The hard carbon negative electrode material is prepared by carrying out pre-oxidation treatment, inert atmosphere pyrolysis, constant-speed cooling and crushing treatment on an animal hair generating substance material. According to the invention, the corresponding relationship among the interlayer spacing, the micropore number and the surface oxygen-containing groups of the animal hair generating substance fiber under the preoxidation-inert atmosphere temperature-changing pyrolysis, the sodium storage capacity and the cycling stability is determined; the rabbit hair-based hard carbon negative electrode prepared under the optimal condition realizes the sodium storage specific capacity of 265.30 mAh g <-1 > and the capacity retention ratio of 88.55% after 300 cycles under the current density of 50mA g <-1 >. The low-cost large-scale preparation scheme of the hard carbon negative electrode material, which can be industrially popularized, provided by the invention provides technical reference for industrial development of the sodium-ion battery.