2168 results about "Doped carbon" patented technology

The present disclosure relates to a carbon-based nanomaterial composition that may be formed from a gas mixture and a sulfur powder. The gas mixture may include a carbon based gas, an oxygen gas, and a hydrogen gas. The carbon-based nanomaterial composition may include sulfur doped nanospheres.

The invention discloses a modified graphite felt electrode for an all-vanadium redox flow battery and a preparation method of the modified graphite felt electrode, and belongs to the technical field of redox flow battery electrode materials. The preparation method comprises the following steps: graphite felt electrochemical oxidation etching treatment; self-assembling a conductive layer on the oxidized and etched graphite felt to obtain the graphite felt attached with the conductive layer; and loading a metal and nitrogen-doped carbon (M and NC) nano catalyst layer on the graphite felt attached with the conductive layer to obtain the modified graphite felt electrode. Various properties of the graphite felt are comprehensively improved through matrix treatment, structure change and load catalysis, mild electrochemical oxidation etching is adopted, a carbon fiber structure is protected, a self-assembled net-shaped conductive layer forms a stable conductive channel, the specific surface area is remarkably increased, a nitrogen-doped carbon shell is adopted to wrap metal nanodots to form an M-NC catalytic layer, and the specific surface area is remarkably increased. The catalyst layer is not easy to dissolve out, the capacity fading rate is obviously improved, the loading capacity of the catalyst layer on the reticular structure conducting layer with a larger specific surface area is larger, and meanwhile, the process is simple and low in cost.

The invention discloses a modified carbon-coated sodium manganese ferric phosphate pyrophosphate / sodium ferric phosphate pyrophosphate positive electrode material as well as a preparation method and application thereof, and relates to the technical field of new energy materials. The preparation method comprises the following steps: preparing MnFe-MOF from a manganese source, a first iron source and a first organic ligand under a hydrothermal reaction; a second iron source, the MnFe-MOF and a second organic ligand are subjected to a hydrothermal reaction, and MnFe-MOF / Fe-MOF is obtained; uniformly mixing with a sodium source and a phosphorus source, and sintering to obtain a positive electrode material; and carrying out high-temperature gas-phase etching treatment to obtain the fluorine-doped carbon-coated modified sodium manganese ferric phosphate pyrophosphate / sodium ferric phosphate pyrophosphate positive electrode material. The material disclosed by the invention has a coating modified structure, so that an interface side reaction caused by direct contact between sodium ferromanganese phosphate and an electrolyte can be effectively avoided, a manganese dissolution phenomenon is reduced, and the structural stability of the material is improved; and meanwhile, the material has high conductivity, excellent structural stability, excellent long cycle life and excellent rate capability.

The invention discloses a high-entropy alloy / nitrogen-doped carbon nano catalytic material and a preparation method and application thereof.The nano catalytic material comprises a high-entropy alloy composed of five non-noble metals including Fe, Co, Ni, Cu and Mn and nitrogen-doped carbon synthesized with the assistance of MOF, the non-noble metal high-entropy alloy serves as a main body material, the nitrogen-doped carbon serves as a carrier material, and the nitrogen-doped carbon serves as a carrier material. A non-noble metal high-entropy alloy is loaded on nitrogen-doped carbon to construct a novel nano catalytic material, and the novel nano catalytic material is used for activating peroxydisulfate to remove antibiotics in a water body. The catalyst has the advantages of excellent chemical stability, good reusability and the like and is a novel nano catalytic material with efficient catalytic performance and environment-friendly characteristics, and the preparation method has the advantages of being simple in operation process, green, environmentally friendly, economical, feasible and the like and can be used for large-scale preparation.

The invention discloses a polypyrrole / cobalt / nitrogen-doped carbon composite material with a coaxial hollow structure and a preparation method thereof, and belongs to the technical field of advanced functional composite materials. The method comprises the following steps: firstly, synthesizing a hollow polypyrrole nanotube by a soft template method; secondly, cobalt / nitrogen-doped carbon is synthesized by adopting a template guiding method; and finally, secondarily coating the outer surface of the cobalt / nitrogen-doped carbon with a polypyrrole layer by adopting an in-situ oxidative polymerization method to construct the polypyrrole / cobalt / nitrogen-doped carbon composite material with a coaxial hollow heterostructure, and the polypyrrole / cobalt / nitrogen-doped carbon composite material has a coaxial sandwich structure: the inner core is a nitrogen-doped carbon hollow tube, the middle layer is a nitrogen-doped porous carbon matrix embedded with cobalt nanoparticles, and the outer surface of the cobalt / nitrogen-doped carbon composite material is a porous carbon matrix embedded with cobalt nanoparticles. And the outer layer is a conductive polypyrrole coating layer. The preparation method provided by the invention can successfully realize in-situ confinement growth and stable combination of ZIF-67, and has the advantages of high repetition rate, high yield and simple method; by adjusting the proportion of polypyrrole in the composite material, good impedance matching and large dielectric loss can be realized, and excellent electromagnetic wave absorption performance can be obtained.

The invention discloses a laser cladding preparation method for improving the wear resistance of a cladding layer by doping tungsten carbide. According to the method, cladding process parameters are preliminarily obtained based on finite element heat flow analogue simulation, cladding layer preparation is carried out, cladding quality characterization is carried out to obtain the optimal cladding process parameters, and finally the cladding layer with the wear-resistant characteristic is obtained. The method comprises the following steps: firstly, constructing a heat flow coupling three-dimensional model, carrying out grid division, establishing a heat source model, defining thermophysical parameters of tungsten carbide (10-15%) nickel alloy composite powder and a matrix, and determining simulated boundary conditions; setting a multi-factor process parameter combination to carry out numerical simulation calculation, and determining laser processing process parameters of laser power, scanning speed and light spot diameter; preparing a cladding layer on the surface of the nodular cast iron by using tungsten carbide (10-15%) nickel alloy composite powder through a laser cladding method; and carrying out microscopic morphology and microhardness experiments to carry out quality analysis verification on the cladding layer, determining the optimal process parameters of laser power, scanning speed and light spot diameter when the cladding layer has no obvious defect morphology and the hardness is higher than that of the raw material, and obtaining the laser cladding preparation method for improving the wear resistance of the cladding layer by doping tungsten carbide. The invention provides a new research method and a high-quality preparation approach for improving the wear resistance of the cladding layer by tungsten carbide, and can be widely applied to the fields of strengthening and repairing mining machinery, aerospace parts and the like.

The invention discloses a metal-doped carbon quantum dot as well as preparation and application of the metal-doped carbon quantum dot in a nano antibacterial agent, citric acid, urea and tea polyphenol are taken as precursors, metal salt is added, carbon dot synthesis and metal ion doping are synchronously completed in one step through a hydrothermal method, and the metal-doped carbon quantum dot is prepared; the surfaces of the metal-doped carbon quantum dots are negatively charged, and the metal-doped carbon quantum dots have peroxidase-like activity and catalase-like activity at the same time; the metal ions adopt any one of Fe < 3 + >, Cu < 2 + > and Ce < 3 + >; the metal-doped carbon quantum dots are in a sphere-like shape. The metal-doped carbon quantum dots prepared by the preparation method disclosed by the invention have peroxidase-like activity and catalase-like activity at the same time through precise doping of metal ions, and the two activities have a synergistic effect in an oral periodontitis microenvironment, so that a good antibacterial effect is achieved.

The invention discloses a biochar / carbon nanotube / myristic acid composite phase change material as well as a preparation method and application thereof, and belongs to the technical field of heat storage. The meat biochar / carbon nanotube / myristic acid composite phase change material is prepared by adopting a vacuum impregnation method. The original biochar is modified by KOH, so that the specific surface area and pore volume of a sample are increased, the specific surface area of the modified KBC3 reaches 813.56 m < 2 > / g, and the loading capacity of the KOH modified biochar on MA is increased to 63%. The result shows that the MA sample is successfully loaded into the porous material, and the structure is kept intact. In order to further improve the loading rate and the leakage resistance of the phase change material, carbon nanotubes are doped in the KBC / MA phase change material, and when the loading rate of MA is improved to 75%, KBC1.5 / MA severely leaks in a shape stability performance experiment, and the mass loss rate reaches 8.5%. And KBC1.5 / CNT1 / MA only has little leakage in the thermal stability test process, so that the leakage resistance of the composite phase change material is greatly enhanced. Through BC modification and CNTs introduction, the heat conduction capability and the photothermal conversion capability of the composite PCMs are greatly improved.

The invention discloses a process for synthesizing ammonia by coupling low-temperature plasma with electro-catalysis in the field of clean energy and green chemical industry, which comprises the following specific steps: mixing air and water vapor, feeding the mixture into a dielectric barrier discharge reactor, filling the reactor with a multi-stage heterojunction gradient doped carbon coated catalyst, generating active gas containing NOx under pulse high voltage, and condensing and then entering an electrocatalytic reduction unit. And an electro-catalysis product enters a photo-thermal separation module integrated with a Janus type photo-thermal electrode, the temperature of the electrode is locally increased under visible light irradiation, NH3 desorption is promoted, and finally high-purity ammonia is obtained through polyimide membrane separation. The multistage heterojunction gradient-doped carbon-coated catalyst adopted in the process is prepared through multiple steps and contains gradient-doped boron, sulfur and Au nanoparticles on the surface, NOx adsorption, electron transport and sintering resistance are synergistically improved, and efficient ammonia synthesis under mild conditions is achieved.

The invention relates to a fluorine-nitrogen co-doped carbon-coated positive electrode material and a preparation method thereof, and the cycle performance of the positive electrode material is effectively improved by arranging a fluorine-nitrogen co-doped carbon-coated layer on the surface of a positive electrode active material. When the positive electrode material is applied to a battery system, the cycle life of the battery can be prolonged.

The invention relates to the field of coating materials, and provides a high-wear-resistance stainless steel-based composite coating which is composed of dumbbell-shaped silver-doped silicon carbide, sea urchin-shaped titanium dioxide, 304 stainless steel powder, NiCrBSi nickel-based autolytic alloy powder and the like. The silver-doped silicon carbide is prepared through sol-gel, high-temperature carbonization and acid pickling, and the titanium dioxide filler is obtained through hydrothermal synthesis and calcination. Supersonic flame spraying deposition is adopted, the compactness and bonding strength are enhanced through laser remelting, and finally the wear resistance, the pollution resistance and the antibacterial performance are improved through vacuum annealing, mechanical polishing and hydrophobic coating modification. The design of dumbbell-shaped silver-doped silicon carbide and urchin-shaped titanium dioxide is adopted, high-wear-resistance, antibacterial and high-binding-force coating performance is achieved, the problems of wear resistance and bacteriostasis are solved, and the coating is suitable for the fields of cabinet door plates and the like.

The invention discloses a synthesis method and application of an iron-aluminum co-doped catalyst, and the synthesis method is characterized by comprising the following steps: S1, dissolving an aluminum metal salt and an iron metal salt in a beaker containing deionized water to obtain a solution A; s2, adding a phosphorus source into the solution A, and adjusting the pH to form a turbid liquid B; s3, biomass is added into the turbid liquid B to be stirred for 30 min, and a solution C is obtained; s4, adding a nitrogen source into the solution C, and drying the beaker in a water bath kettle; mixing the obtained dried product with an activating agent, and calcining under inert gas to obtain a catalyst crude product; and S5, grinding the catalyst crude product, washing with ethanol and deionized water, and carrying out vacuum drying to obtain the iron-aluminum co-doped catalyst. The preparation method is simple and low in equipment requirement. The invention discloses a novel nitrogen-doped carbon-coated zero-valent iron nanoparticle catalyst which can degrade pollutants by utilizing electron transfer of the pollutants and the catalyst under the condition of adding any oxidizing agent. Under the neutral room temperature condition, the catalyst has a very good removal effect on degradation of organic pollutants which are difficult to biodegrade, has very good stability, and is low in iron ion dissolution rate.

A nanocomposite electrode and a supercapacitor device including said nanocomposite electrode. The nanocomposite electrode includes a mixture of at least one binding compound, at least one conductive additive, and at least one molybdenum doped carbon material coated onto a substrate. The supercapacitor device includes two nanocomposite electrodes disposed facing one another, wherein the substrate of each nanocomposite electrode is coated with the mixture on an inside facing surface and the outer surfaces of the nanocomposite electrodes are not coated with the mixture, and the inside facing surfaces are separated by at least one electrolyte.

The invention relates to a high-compaction lithium iron phosphate positive electrode material, a preparation method thereof and a lithium ion battery, and belongs to the technical field of batteries, the method adopts a two-step synthesis method, the first step adopts ferrous phosphate high-grinding sintering to prepare first-sintering large particles, and adopts in-situ doped iron phosphate low-grinding to prepare first-sintering small particles; 2, performing high grinding on the first-fired large particles, performing low grinding on the first-fired small particles, accurately controlling the sizes of the small particles, and stripping C3N4 through grinding to form g-C3N4; the large and small particles are mixed according to a certain mass ratio, and then secondary sintering is carried out to prepare the high-compaction high-capacity long-circulation lithium iron phosphate material, the advantages of different precursors are utilized, the particle composition is optimized, and the roundness of the large and small particles is better; meanwhile, the nitrogen-doped carbon layer is prepared by taking defect-type graphene and high-molecular organic nitride which are converted from C3N4 in a secondary sintering process as carbon sources, so that the conductivity and the cycle performance of the material are improved.

The invention relates to a carbon nanofiber loaded Cu nanoparticle composite material prepared by combining an electrostatic spinning method and a high-temperature in-situ reduction reaction and used as a high-cycle-stability zinc negative electrode coating of an aqueous zinc ion battery. Belongs to the technical field of new energy materials. The prepared composite electrode material is regular in structure and excellent in electrochemical performance. Cu is introduced through a high-temperature in-situ reduction reaction. And after the Cu is loaded with the carbon nanofibers, not only is the slow dynamic process of the bare zinc electrode improved, but also the uniform deposition of Zn < 2 + > on the zinc negative electrode in the embedding / separating process is induced.

The invention relates to the technical field of composite catalyst materials, in particular to a ferrocobalt bimetal hydroxide / BCN composite material and a preparation method and application thereof.The preparation method comprises the steps that cobalt nitrate and ferric nitrate are used for preparing a metal salt solution, sodium carbonate and sodium hydroxide are used for preparing a precipitant solution, a B-doped carbon nitride BCN material is added into the metal salt solution to form a uniform suspension, and the suspension is dried to obtain the ferrocobalt bimetal hydroxide / BCN composite material; dropwise adding the precipitant solution into the suspension to obtain a precursor solution, performing hydrothermal reaction on the precursor solution, and performing centrifugal impurity removal and drying to construct a heterostructure between layered double hydroxide and BCN in situ to obtain the Co-Fe LDH-coated BCN composite material. Through boron doping and heterostructure construction, the charge separation capacity of graphite carbon nitride is enhanced, the electron migration efficiency is improved through a heterointerface structure, the metal ion release amount and the cycle stability are controlled, and the catalytic performance is remarkably improved.

The invention discloses a composite coated silicon-carbon negative electrode material as well as a preparation method and application thereof, and relates to the technical field of lithium ion batteries. The method comprises the following steps of: oxidizing and etching graphite in mixed gas of air and nitrogen at the temperature of between 400 and 500 DEG C to form graphite oxide; the preparation method comprises the following steps: dispersing water-soluble asphalt, graphene, nano silicon, melamine and monoammonium phosphate in water to form a composite liquid; and then mixing the composite liquid with graphite oxide, and then carrying out carbonization treatment. The high-performance silicon-carbon composite negative electrode material is prepared through graphite oxidation etching and a composite coating process, nano silicon is uniformly dispersed in carbon pores which are stably combined on the surface of graphite and have rich mesoporous structures, graphene and a nitrogen-doped carbon layer form a three-dimensional conductive network, and the composite negative electrode material is applied to lithium ion batteries and can be applied to lithium ion batteries. And the lithium ion battery has good low-temperature charging proportion, first efficiency and cycle performance.

The invention discloses a silk protein-MXene composite film and a preparation method thereof. The silk protein-MXene composite film sequentially comprises a conductive surface layer, a porous response layer and a supporting bottom layer from top to bottom, the invention relates to the technical field of composite films. According to the fibroin-MXene composite film and the preparation method thereof, a three-layer gradient structure is formed by the conductive surface layer, the porous response layer and the supporting bottom layer, good conductivity and electromagnetic shielding effectiveness are ensured by utilizing oriented arrangement of MXene of the conductive surface layer, gallic acid and MXene form a hydrogen bond network, and nitrogen-doped carbon quantum dots coat the surface of MXene to form a physical barrier, so that the electromagnetic shielding effect is improved, and the electromagnetic shielding effect is improved. Through double oxidation resistance of gallic acid and nitrogen-doped carbon quantum dots, a sponge body structure formed by the porous response layer is matched to endow the composite film with high-sensitivity response to external stimulation, the supporting bottom layer is crosslinked by hexamethylene diisocyanate and enhanced by nanocellulose, the tensile strength is improved, and the tensile strength of the composite film is improved. And the contradiction between the mechanical property and the conductivity of the traditional composite film is effectively solved.

The invention relates to the technical field of environmental functional materials and water treatment, and discloses a preparation method and application of a persulfate activator for efficiently removing drug-resistant bacteria and drug-resistant genes in water. Waste biomass and waste plastics are used as raw materials, solid waste resource utilization is achieved through synergistic pyrolysis, compared with a traditional catalyst, the preparation cost can be reduced by more than 40%, and remarkable economic and environmental benefits are achieved. The catalyst has the following advantages: 1) the limitation of a traditional single-active-site catalyst is broken through through the triple synergistic effect of transition metal oxide variable valence activation, nonmetal doped carbon electron conduction and an oxygen vacancy non-free radical path; 2) physical interception of ARB and enrichment of ARGs can be realized at the same time by utilizing a multi-stage pore channel structure; and (3) activating persulfate to generate free radicals (SO4 <->. / . OH) and non-free radicals (1O2 / electron transfer) to generate a double-path synergistic effect, thereby realizing efficient removal of ARB / ARGs in water.

The invention discloses a fluorine-nitrogen-doped carbon-based oxygen reduction electrocatalyst for a zinc-air battery and a preparation method of the fluorine-nitrogen-doped carbon-based oxygen reduction electrocatalyst, and belongs to the technical field of catalysts. According to the method, a fluorocarbon mixture is rapidly treated through Joule heat to achieve efficient fluorine doping, then nitrogen doping is conducted through an ammonia gas plasma technology, and therefore an original carbon precursor is converted into fluorine-nitrogen-doped carbon. The catalyst material is short in preparation time and high in production efficiency, the content configuration of fluorine and nitrogen doped in fluorine-nitrogen-doped carbon finally formed by accurately controlling the temperature and time of Joule heat treatment and the power and time of plasma treatment is controllable, the morphology and the pore structure are controllable, high electro-catalytic performance is guaranteed, and the catalyst material is suitable for industrial production. The preparation method is high in production efficiency and low in cost, and has large-scale amplification potential.

The invention relates to a preparation method and application of a cobalt-doped porous carbon nitride nanosheet, and the preparation method comprises the following steps: (1) taking a nitrogen source and a cobalt source as raw materials, grinding the nitrogen source and the cobalt source, uniformly mixing, calcining at high temperature, naturally cooling to room temperature, washing the calcined substances of the nitrogen source and the cobalt source, and drying in vacuum to obtain the cobalt-doped carbon nitride nanosheet; and (2) dispersing the cobalt-doped carbon nitride nanosheet obtained in the step (1) in hydrazine hydrate for heating reaction, washing the cobalt-doped carbon nitride nanosheet to be neutral after the heating reaction is finished, and finally performing vacuum drying to obtain the cobalt-doped porous carbon nitride nanosheet. The cobalt-doped porous carbon nitride nanosheet prepared by the method disclosed by the invention is a catalytic material which is high in response capability to visible light, high in yield of hydrogen peroxide prepared by photocatalysis, good in decomposition inhibition performance and capable of being repeatedly used, and is suitable for the field of new energy products.

An electrode structure for a solid-state or semi-solid-state battery is provided in which NCM electrode particles coated with an interphase layer and a nitrogen-containing carbon layer are disposed. [Solution] The NCM electrode particles comprise NCM (nickel-cobalt-manganese oxide) particles (15), primary particles (30) that coat the outer surfaces of the NCM particles, an interphase layer (16) that includes a glass phase layer (241) and a plurality of ceramic particles (242), and a nitrogen-containing carbon layer (35) that coats the exterior of the primary particles. Nitrogen-doped carbon molecules in the nitrogen-containing carbon layer aid in the conduction of electrons and lithium ions, modifying the electrical potential of the NCM particles. The nitrogen-containing carbon layer is formed by coating the surfaces of the primary particles with a nitrogen-containing polymer material and calcining the material in an inert atmosphere. Conjugated bonds are formed between the carbon and nitrogen, modifying the energy band structure, reducing the energy required for electrons to transition to the conduction band, and improving overall electronic conductivity.

The invention relates to the technical field of batteries, in particular to a negative electrode material, a preparation method thereof and a battery. The negative electrode material comprises a silicon nano material; the metal silicide layer at least partially coats the surface of the silicon nano material; the nitrogen and sulfur doped carbon layer at least partially coats the surface of the metal silicide; and the thickness of the metal silicide layer is greater than that of the nitrogen and sulfur doped carbon layer. According to the negative electrode material, the preparation method thereof and the battery provided by the invention, the coating structure of the negative electrode material is optimized, and the metal silicide / heteroatom doped carbon double-layer coated silicon nano material can be prepared by adopting a synthesis method which is low in energy consumption and capable of constructing a functional multi-layer coating structure, so that the long cycle life and the high-rate fast charging performance can be considered at the same time.

The invention discloses a nitrogen-doped carbon-supported transition metal monatomic material as well as a preparation method and application thereof, and belongs to the technical field of inorganic catalyst materials. The preparation method provided by the invention comprises the following steps: (1) grinding a mixture containing a transition metal precursor, a nitrogen source and a carbon source to obtain an initial mixture; and (2) pyrolyzing the initial mixture in an inert gas atmosphere to obtain the nitrogen-doped carbon-supported transition metal monatomic material. The material provided by the invention can efficiently catalyze carbon dioxide to be reduced into carbon monoxide in a carbon dioxide saturated potassium bicarbonate electrolyte, and the selectivity is higher than 90% or above. The preparation method provided by the invention has universality, is easy for large-scale production, and can be used for synthesizing other similar monatomic materials. The nitrogen-doped carbon-supported transition metal monatomic material prepared by the invention is applied to electrochemical carbon dioxide reduction as an electrocatalyst, and can show excellent catalytic activity, selectivity and stability.

The invention discloses a silicon / graphite / carbon-aluminum oxide composite negative electrode material and a green preparation method thereof, and belongs to the technical field of lithium ion batteries. Aiming at the problems of high volume expansion rate and poor cycling stability of a silicon-based negative electrode and high cost of a traditional process, the invention innovatively provides the following scheme: 1) waste photovoltaic silicon wafer ball-milling liquid and waste graphite are taken as core raw materials, and resource recycling is realized; (2) phenolic resin and chitosan are adopted as double carbon sources, a nitrogen-doped carbon layer (the nitrogen content is 3-5 wt.%) is formed through pH-induced self-assembly, and the conductivity and the Li < + > diffusion rate are synchronously improved; and 3) aluminum nitrate is introduced for pyrolysis to generate 2-5nm aluminum oxide for doping, so that the side reaction of the electrolyte is inhibited, and the volume expansion of silicon is relieved (the expansion rate is less than or equal to 120%). The preparation process comprises the steps of silicon / graphite dispersion, double-carbon-source compounding, ammonia water regulation and control precipitation and gradient calcination. Experiments show that the specific capacity of the optimized material under the current of 0.5 A / g reaches more than 800mAh / g, the 100-time cycle capacity retention ratio is more than 98%, the 1000-time cycle capacity retention ratio is more than 80%, the reversible specific capacity under the multiplying power of 3A / g is more than 550mAh / g, and the raw material cost is reduced by 40%. The invention has the advantages of high capacity, long service life, environmental protection and economy, and provides an innovative solution for the fields of power batteries and energy storage.

The invention discloses a 3d transition metal M-rare earth metal R bi-component doped carbon-supported Pt catalyst as well as a preparation method and application thereof, relates to a catalyst taking doped carbon as a carrier to support Pt as well as a preparation method and application thereof, and aims to solve the problem that the existing Pt / C catalyst is poor in catalytic activity and stability. Wherein M is Fe, Co, Ni or Zn, and R is Ce, Nd or Gd. The preparation method comprises the following steps: carrying out complexing growth on M and R ions and a nitrogen source ligand on the carbon surface, and then carrying out high-temperature carbonization to obtain an M-R bi-component doped carbon carrier; the preparation method comprises the following steps: preparing an M-R two-component doped carbon-carbon supported Pt catalyst by using a microwave reduction method, then loading Pt by using a microwave reduction method to obtain the M-R two-component doped carbon-carbon supported Pt catalyst, the mass activities of Pt / Fe-Ce-NC and Pt / Co-Ce-NC are respectively 0.27 A / mgPt and 0.22 A / mgPt and are 2.8 times and 2.3 times that of Pt / C, and the M-R two-component doped carbon-carbon supported Pt catalyst can be used in the field of proton exchange membrane fuel cells.

According to the present invention, there is provided a monatomic catalyst, the monatomic catalyst comprising: a nitrogen-doped carbon structure; and a monatomic metal wherein the monatomic metal forms a coordinate bond with a nitrogen atom of the nitrogen-doped carbon structure. When an electrochemical cell having an electrode pair containing the monatomic catalyst is used in an electrochemical advanced oxidation process for water treatment, organic pollutants in wastewater can be effectively decomposed under mild pH conditions.

The present invention belongs to the technical field of battery materials, and particularly relates to a composite phosphate-based positive electrode material, and a preparation method therefor and the use thereof. The composite phosphate-based positive electrode material comprises a phosphate-based active core, wherein the outer surface of the phosphate-based active core is sequentially coated with a carbon coating layer, a nitrogen-doped carbon coating layer and a nitrogen-phosphorus co-doped carbon coating layer from inside to outside, wherein the carbon coating layer can improve the electronic and ionic conductivity of the composite positive electrode material, and optimize the particle size and morphology of the composite positive electrode material. The nitrogen-doped carbon coating layer improves the consistency and integrity of coating; and nitrogen-atom-doped carbon further enhances the electronic conductivity and lithium-ion diffusion of the carbon coating layer. Electron-rich clouds of P and N atoms in the nitrogen-phosphorus co-doped carbon coating layer can provide a rich conductive network, mutual contact is formed among different particles to form a series network, thus promoting the interfacial electron transport of the composite material during a charging and discharging process, and improving the cycling and rate performance of the composite phosphate-based positive electrode material during the charging and discharging process.

The invention discloses a nitrogen-doped carbon material composite tin-antimony alloy oxygen reduction reaction catalyst. The nitrogen-doped carbon material composite tin-antimony alloy oxygen reduction reaction catalyst comprises a nitrogen-doped carbon material carrier and tin-antimony alloy particles uniformly loaded on the surface and inside of the nitrogen-doped carbon material carrier. The preparation method comprises the following steps: S1, dissolving a precursor of a nitrogen-containing carbon material in an organic solvent to obtain a precursor solution; s2, adding a template agent into the precursor solution until the template agent is completely dispersed, then adding soluble salt of tin and soluble salt of antimony, and uniformly stirring to obtain a raw material solution; and S3, carrying out freeze drying treatment on the raw material solution, then introducing the raw material solution into a reducing atmosphere, carrying out high-temperature calcination treatment, and then carrying out washing treatment to remove the template agent. The invention discloses a nitrogen-doped carbon material composite tin-antimony alloy oxygen reduction reaction catalyst which is novel in composition, has a good pore structure and a high specific surface area, and not only has excellent oxygen reduction reaction catalytic activity, but also has relatively high stability.

The invention provides a negative electrode active material and a preparation method thereof, a negative electrode for a sodium ion battery, the sodium ion battery and an electric device. The negative electrode active material comprises a nitrogen-doped carbon sphere matrix and manganese monoxide embedded into the nitrogen-doped carbon sphere matrix, the average particle size of the manganese monoxide is 1.5 nm to 2.5 nm. In the negative electrode active material, the quantum-dot-level MnO is embedded into the nitrogen-doped carbon sphere matrix, so that a tight embedded structure (non-surface loading) of the quantum-dot-level MnO and the nitrogen-doped carbon spheres can be realized, volume expansion when sodium ions are embedded and removed is effectively relieved, and an efficient electron / ion transmission channel is provided. Meanwhile, the quantum dot-level MnO has a larger specific surface area, and provides more adsorption sites with the nitrogen-doped carbon, so that the composite material shows a pseudocapacitance-dominated sodium storage behavior, and is endowed with ultrahigh rate capability and ultra-long cycle life.