398 results about "Mesoporous carbon" patented technology

The invention provides a sodium ion battery, an energy storage device and an energy storage system. The sodium ion battery comprises a positive pole piece, a diaphragm, a negative pole piece and an electrolyte, the negative pole piece comprises a carbon material, the specific surface area of the carbon material is x, the carbon material comprises mesopores, the number percentage of the mesopores in the carbon material is y, and the electrolyte comprises an organic solvent, an electrolyte salt, an organic additive and a sodium salt additive, the organic solvent comprises cyclic carbonate and chain carbonate, the mass fraction of the cyclic carbonate in the electrolyte is a, the mass fraction of the chain carbonate in the electrolyte is b, the mass fraction of the organic additive in the electrolyte is c, and the mass fraction of the sodium salt additive in the electrolyte is d; the sodium ion battery meets the relational expression of 0.4 < = a / y < = 0.8; 0.5 < = a / b < = 1.3; 0.4 < = c / x < = 1.2; and 0.1 < = d / c < = 0.5.

The invention relates to the technical field of mesoporous carbon material preparation, in particular to a high-temperature mesoporous carbon preparation method which comprises the following steps: S1, mixing a metal halide and an inorganic hydrogen bond donor, and heating and stirring until a solution is clear to obtain an inorganic eutectic solvent; s2, mixing the inorganic eutectic solvent and a biomass raw material for reaction; s3, filtering and washing the material obtained in the step S2; and S4, carbonizing the material obtained in the step S3 in a high-temperature inert atmosphere to obtain the high-temperature mesoporous carbon. According to the method, the wood fiber biomass such as the lowest-value straw, the lowest-value bamboo and the lowest-value wood dust is directly used as raw materials, component separation does not need to be conducted on the wood fiber biomass, and high-value utilization of a large amount of low-value wood fiber biomass can be achieved. The method is relatively simple in process, relatively mild in condition and relatively high in product yield, and an activating agent does not need to be used. The biomass mesoporous carbon prepared by the method also has a high specific surface area in a huge mesoporous volume state, and the specific capacitance in an alkaline electrolyte exceeds 260F / g.

The invention relates to an external composition for hair growth regulation and a preparation method thereof, and belongs to the technical field of cosmetics and medicines. The composition disclosed by the invention comprises nano mesoporous carbon for enhancing permeation, various surface functional modifications on the nano mesoporous carbon, minoxidil, protein fragments, polypeptides, oligopeptides, amino acids, dutasteride, bimatoprost, traditional Chinese medicine extracts, vitamins, caffeine, nucleosides, growth factors and various auxiliary functional components. Wherein the pore diameter of mesopores of the nano mesoporous carbon for enhancing permeation is 2-30 nm, the total pore volume of the mesopores is 1.5-3.5 cm < 3 > / g, and the particle size of the nano mesoporous carbon is 50-200 nm. The prepared nano mesoporous carbon is granular, controllable in size, stable in structure, free of irritation to skin, capable of keeping inert to various active ingredients in the composition, capable of enhancing absorption and permeation of other ingredients on the skin, wide in application range, capable of compounding various types of active ingredients and high in biological safety.

The invention relates to a hollow mesoporous carbon sphere prepared based on a confinement polymerization method and a preparation method of a platinum alloy catalyst loaded by the hollow mesoporous carbon sphere and doped with rare earth metal. The method comprises the following steps: by taking mesoporous silica as a template, introducing an initiator and a small molecular organic matter precursor into mesopores, and carrying out confinement polymerization in the mesopores to obtain a silica / polymer composite; carrying out high-temperature calcination and etching treatment on the complex to obtain hollow mesoporous carbon spheres; the carbon sphere is used as a carrier to load a platinum alloy doped with rare earth metal. The hollow mesoporous carbon spheres prepared by the method have good spherical morphology and mesoporous channels and high specific surface area, and the problems of non-uniform morphology, unobvious mesopores and the like in a traditional method are solved. After platinum alloy particles doped with rare earth metal are loaded on the carbon spheres, the problems of agglomeration, wide particle size distribution, poor performance and the like of the platinum alloy particles are solved.

The invention relates to the technical field of preparation of nano catalytic materials, in particular to a preparation method of hierarchical pore channel mesoporous carbon loaded metal nanoparticles. According to the invention, biomass diatomite is used as a template to construct a vertically through macroporous channel, a block copolymer is introduced to form an ordered mesoporous structure, and a pore-foaming agent is added to generate a macro-pore network in a pyrolysis process, so that a macro-pore-mesoporous-micropore three-level communicated carbon-based skeleton is realized; and a bimetallic component is loaded on the hierarchical porous mesoporous carbon in a gradient confinement manner. The material disclosed by the invention has the advantages of fast mass transfer of macropores, stable nanoparticles of mesoporous confinement and efficient catalysis of monatomic sites, and can efficiently catalyze and degrade various wastewater organic pollutants in a wide pH range.

The invention discloses a preparation method and application of a high-nitrogen-doped ordered mesoporous carbon supported copper catalyst, and belongs to the technical field of catalyst preparation. The preparation method comprises the following steps: by taking cane sugar and a copper-nitrogen complex as raw materials, SBA-15 as a template agent and sulfuric acid as a catalyst, carrying out equivalent-volume impregnation, low-temperature heat treatment, 800-900 DEG C high-temperature carbonization and nitric acid / hydrofluoric acid demolding to prepare pyrrole nitrogen enriched or pyridine nitrogen enriched high-nitrogen doped ordered mesoporous carbon with a large specific surface area; the preparation method comprises the following steps: loading a copper species on high-nitrogen-doped ordered mesoporous carbon by adopting an equivalent-volume impregnation method, and reducing at 350-400 DEG C to prepare the high-nitrogen-doped ordered mesoporous carbon loaded copper catalyst. The prepared catalyst is high in nitrogen content, large in specific surface area, high in pyridine nitrogen or pyrrole nitrogen enrichment degree and uniform in copper particle dispersion and shows efficient catalytic performance in methanol oxidative carbonylation reaction, and the highest methanol conversion rate is 9.3%.

The invention relates to the technical field of mesoporous materials, and discloses an ordered mesoporous phenolic resin sphere, an ordered mesoporous carbon sphere and a preparation method and application thereof. The ordered mesoporous phenolic resin sphere has a uniform spherical morphology and a highly ordered mesoporous structure, the particle size of the ordered mesoporous phenolic resin sphere is 40-2000nm, and the aperture of the ordered mesoporous phenolic resin sphere is 3-10nm; the solid content reaches 100g / L. The preparation method comprises the following steps: dissolving a surfactant in a composite solvent, and uniformly stirring to obtain a precursor solution; dissolving a phenolic precursor and formaldehyde in the precursor solution, and slowly adding a pore-enlarging agent to obtain a uniform emulsion; adding a catalyst into the emulsion to carry out polymerization reaction; and after the reaction, collecting a solid phase, and carrying out heat treatment in an inert atmosphere to obtain the ordered mesoporous phenolic resin spheres. The ordered mesoporous phenolic resin spheres and the ordered mesoporous carbon spheres have uniform spherical structures, highly ordered mesoporous structures and high solid content; the preparation method is simple in process, high in expansibility and beneficial to large-scale production.

The invention belongs to the technical field of CO2 adsorbents, relates to carbon-based solid amine, and discloses a preparation method of a carbon-based solid amine CO2 trapping adsorbent, which comprises the following steps: S1, dissolving organic amine in a methanol solution to form a methanol amine solution; s2, adding the mesoporous carbon-based carrier into the methanol amine solution, and stirring at a low speed to evaporate methanol; and S3, drying in a vacuum oven to obtain the carbon-based solid amine CO2 trapping adsorbent. The CO2 trapping adsorbent prepared by the invention has the advantages of large CO2 adsorption capacity, strong selectivity, good stability and reproducibility, effectively reduces the CO2 trapping cost, and has huge advantages in the aspect of carbon trapping.

The invention provides a modified silicon-based negative electrode material as well as a preparation method and application thereof, and relates to the technical field of new energy battery negative electrodes. The preparation method provided by the invention comprises the following steps: dipping a boron-silicon substrate in a pre-lithium solution, evaporating a solvent to dryness, and calcining to obtain a modified substrate; growing silicon nitride nanowires on the surface of the modified matrix in situ to prepare a composite matrix; and reducing the composite matrix in a reducing atmosphere, and coating the surface with mesoporous carbon to prepare the modified silicon-based negative electrode material. The structure stability of the negative electrode material in the charging and discharging process can be effectively improved, the cycle performance reduction caused by the pulverization of the negative electrode material is avoided, and meanwhile, the first effect can be improved by performing pre-lithiation on the boron-silicon substrate.

The invention provides a mesoporous silicon carbon negative electrode material and a preparation method and application thereof, and relates to the technical field of battery negative electrode materials, the mesoporous silicon carbon negative electrode material comprises a mesoporous carbon matrix and silicon; the mesoporous carbon matrix can be a spherical, spheroidic or irregular block, the mesoporous carbon matrix has mesoporous structures, and preferably, the mesoporous structures are in ordered distribution; according to the invention, the preparation of the uniform mesoporous structure is realized, the volume expansion of the silicon is effectively relieved, the close combination of the silicon and the carbon is realized by vapor deposition of the silicon on the mesoporous sphere carbon matrix material, and the cycling stability of the material is improved. According to the meso-porous silicon carbon negative electrode material provided by the invention, by optimizing the structural design of the material, the problems of silicon volume expansion, infirm interface bonding, complex preparation process and the like in the prior art are solved.

The invention discloses phenolic resin-based nitrogen-doped mesoporous carbon as well as a preparation method and application thereof. According to the invention, phenolic resin is used as a carbon source, mesoporous carbon is prepared through rapid carbonization and activation by using a template method and a high-temperature thermal shock technology, accurate regulation and control of nitrogen doping and mesoporous structures are realized in the process, and the specific surface area, conductivity and thermal stability of mesoporous carbon are improved; the electrochemical reaction activity and stability of the mesoporous carbon carrier are remarkably improved, and the problems of long activation time, non-uniform pore structure and the like of a traditional method are solved, so that the application range of the mesoporous carbon carrier in the fields of electrochemical energy storage and catalysis is widened.

The invention discloses a detection system and method for measuring trace Cr in tobacco, and relates to the technical field of tobacco detection.The system comprises a multi-stage dynamic digestion module, a two-channel solid-phase microextraction module, a high-resolution ICP-MS detection module, an intelligent data processing module, a collision reaction tank (CRC) based on the high-resolution ICP-MS module and a dynamic background correction algorithm. The detection limit of Cr is as low as 0.008 [mu] g / kg by combining the enrichment capacity of 50 times or more of two-channel solid-phase microextraction (DSPME), the detection limit is reduced by one order of magnitude compared with that of a traditional atomic absorption method (0.1 [mu] g / kg), the accurate determination requirement of trace Cr is met, the two-channel DSPME module is designed through physical isolation of amino magnetic nanoparticles (Cr (III) adsorption) and DTC mesoporous carbon (Cr (VI) adsorption), and the detection limit of the trace Cr is reduced by one order of magnitude compared with that of the traditional atomic absorption method (0.1 [mu] g / kg). And independent capture and elution of Cr (III) and Cr (VI) are realized.

The invention discloses a preparation method and application of a carbon dioxide hydrogenation catalyst, and belongs to the field of hydrogenation catalysis. The vanadium slag is used as a raw material, a leaching solution containing silicon, chromium and vanadium is obtained through sodium salt roasting, an aluminum source is added to remove the silicon element, meanwhile, an ordered mesoporous carbon material is added, and silicon and aluminum elements are converted into an ordered mesoporous composite oxide which is used as a hydrogenation catalyst carrier; an indium salt, a cerium salt and a nickel salt are dissolved in ethanol and mixed with the carrier for isopyknic impregnation to obtain the hydrogenation catalyst; and carrying out chromium and vanadium separation on the silicon-removed leaching solution to obtain chromium sesquioxide and the all-vanadium redox flow battery electrolyte. The catalyst has a regular pore structure, ordered mesopores provide a confinement effect, dispersion and anchoring of active components are facilitated, and the activity of the catalyst is remarkably improved.

A method of mesoporous carbon support production includes providing an active silica template from a self-assembling block copolymer (BCP) in a solution, the BCP including a diblock copolymer of polydimethylsiloxane (PDMS) as a majority block and a hydrocarbon polymer as a minority block in a predetermined volume fraction, the BCP being in a form of nanodroplets, drying and annealing the nanodroplets, ashing away the hydrocarbon polymer of the minority block to obtain the active silica template, applying a carbon precursor onto the active silica template, and removing the active silica template to obtain a mesoporous carbon support as a reverse image of the template.

The invention provides a heterostructure salinity difference energy conversion film based on HOF / two-dimensional mesoporous carbon as well as a preparation method and application of the heterostructure salinity difference energy conversion film. The salinity difference energy conversion film comprises a two-dimensional mesoporous carbon layer serving as a hydrophobic layer and a hydrogen bond organic framework layer which covers one surface of the hydrophobic layer and serves as a hydrophilic layer, wherein the two-dimensional mesoporous carbon layer is formed by compounding a two-dimensional mesoporous carbon material with regular nanopores and aramid nanofibers; the hydrogen bond organic framework layer is formed by compounding a hydrogen bond organic framework material and aramid nanofibers; the heterogeneous Janus structure salinity gradient energy conversion membrane is constructed by adopting a hydrogen bond organic framework and a two-dimensional mesoporous carbon material, and when the heterogeneous Janus structure salinity gradient energy conversion membrane is applied to salinity gradient energy conversion, high ion selectivity, high structural stability and high ion migration flux can be considered.

The invention discloses an asymmetric magnetic mesoporous carbon superstructure material as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) preparing Fe3O4amp; a SiO2 alcohol dispersion liquid; (2) preparing Fe3O4 < 4 > amp; the preparation method comprises the following steps: preparing a SiO2 (at) micro single micelle superstructure alcohol solution; (3) preparing Fe3O4 < 4 > amp; a SiO2 (at) C superstructure material; the specific surface area of the material is 87-116 m < 2 > / g, the aperture is 22.8-50 nm, and the length is 330-400 nm. The material is applied to catalytic degradation of organic dyes. The method has the beneficial effects that the surface chemical property is more active, the hydrophilicity and the catalytic degradation capability are stronger, the method is suitable for chemical catalytic degradation, the whole synthesis process is simple and convenient to operate, and intermediate byproducts cannot be generated to cause secondary pollution; in addition, in the dopamine carbonization process, high-temperature carbonization is carried out in nitrogen (inert atmosphere), and the operation is safe; by adjusting the type of the PS-PVP-PEO single micelle, accurate control of the mesoporous size can be realized, so that the PS-PVP-PEO single micelle is suitable for catalytic degradation of organic pollutants with different molecular weights, and selective catalytic degradation is realized.

The present application relates to the technical field of nano-catalytic material preparation, in particular to a preparation method of multi-stage pore mesoporous carbon loaded metal nanoparticles, which constructs vertical and through macroporous channels by taking biomass diatomite as a template, forms ordered mesoporous structure by introducing block copolymer, and realizes macro-pore-mesopore-micropore three-stage communication of carbon-based skeleton by adding porogen to produce macro-porous network in the pyrolysis process, and gradientally limits and loads bimetallic components on the multi-stage pore mesoporous carbon. The material has the advantages of macroporous rapid mass transfer, mesoporous limited stable nanoparticles and single-atom site efficient catalysis, and can efficiently catalyze and degrade various wastewater organic pollutants in a wide pH range.

The invention discloses a nitrogen-doped multilayer rose-shaped hard carbon material as well as a preparation method and application thereof, and belongs to the technical field of battery materials. A precursor of the nitrogen-doped multi-layer rose-shaped hard carbon material is prepared by adopting a solid-liquid self-assembly method, and then the precursor is calcined, so that the final nitrogen-doped multi-layer rose-shaped hard carbon material can be obtained. The prepared nitrogen-doped porous carbon material has more mesopores and defects, is unique in structure and uniform in shape, and can be used as a sodium ion battery negative electrode material. The nitrogen-doped multilayer rose-shaped hard carbon material prepared by the invention is a material with immunity to environmental influence, belongs to a mesoporous carbon material with stable chemical components and controllable shape in the porous field, has the advantages of regular structure, relatively good stability and the like, and has the properties of high capacity, good rate and the like as a negative electrode material.

The invention relates to a lithium metal negative electrode and a preparation method thereof, a lithium metal battery, a battery pack and electric equipment. The lithium metal negative electrode comprises a lithium metal layer and a porous coating which are laminated, the porous coating comprises a lithium-loving metal component and a nitrogen-containing mesoporous carbon material. The porous coating disclosed by the invention comprises the lithium-loving metal component and the nitrogen-containing mesoporous carbon material, the nitrogen-containing mesoporous carbon material is utilized to provide enough buffer space for deposition of Li ions, and nitrogen and the lithium-loving metal are utilized to further provide affinity sites for Li deposition and inhibit generation of lithium dendrites, so that the charging capacity and the cycling stability of the battery are effectively improved.

The invention discloses a lithium iron phosphate positive electrode material, a positive plate and a preparation method thereof. The material comprises a LiFePOO core with (010) crystal face preferred orientation (the orientation degree is larger than 80%) and a gradient carbon coating layer, the core is co-doped with Ti and F (Ti occupies Li sites, F replaces O sites, and the doping amount x is 0.02-0.08), and the gradient carbon coating layer sequentially comprises microporous carbon, mesoporous carbon and a macroporous carbon / graphene composite layer from inside to outside. The preparation method comprises an optimized liquid phase coprecipitation-segmented sintering process, and comprises the steps of compounding a carbon source in a specific proportion, precisely controlled freeze drying and gradient sintering. The material has excellent ion / electron transmission performance, the 0.2 C specific capacity is greater than or equal to 155mAh / g, the 5C capacity retention ratio is greater than 95%, the low-temperature performance at-40 DEG C is excellent, and the 2000-cycle capacity retention ratio is greater than 90%. The invention also provides a positive plate and a lithium ion battery containing the material, and the positive plate and the lithium ion battery are particularly suitable for high-power power batteries and extreme environments.

The invention discloses a multi-cavity mesoporous carbon nanosphere battery material and a preparation method and application thereof, and belongs to the technical field of ion batteries, the method comprises the following steps: mixing a cosolvent and a surfactant, and stirring until the cosolvent and the surfactant are dissolved; adding a carbon source monomer, and stirring until dissolving; adding a pore-foaming agent, and stirring to form a suspension; and finally, adding a hydrogen bond catalyst, and after the stirring reaction is finished, washing, freeze-drying and carbonizing to obtain the multi-cavity mesoporous carbon nanosphere battery material. The problems of poor micelle stability and low repeatability of a traditional soft template method are solved through cooperative regulation and control of catalysis of the hydrogen bond catalyst and precise assembly time. By simply controlling the reaction time, a product with the multi-cavity structure reaching 65.3%-92.5% is stably and repeatedly prepared and far exceeds 31.7% of that of a non-catalytic system, and precise customization of the microstructure of the material is achieved. The multi-cavity structure can better buffer the volume change caused by sodium ion intercalation / deintercalation in the charging and discharging process, and is beneficial to maintaining the structural integrity of the electrode material.

The invention discloses a coal mine return air corner CO purification method based on catalytic oxidation, and relates to the technical field of coal mine return air corner CO purification, the coal mine return air corner CO purification method comprises the following steps: mixing manganese salt, cerium salt and a complexing agent by adopting a sol-gel coprecipitation method, stirring to form sol, and sequentially drying and calcining at high temperature to prepare a Mn-Ce-O composite oxide catalyst precursor; loading the Mn-Ce-O composite oxide catalyst precursor on a mesoporous carbon carrier subjected to hydrophobic modification treatment through an impregnation method, and carrying out drying and inert atmosphere heat treatment to obtain the low-temperature adaptive composite catalyst with an oxygen vacancy structure and moisture resistance, forming the low-temperature adaptive composite catalyst into a regular structure unit, filling the regular structure unit into a front end area of a reactor to form a first catalyst layer, filling a downstream area of the reactor with a thermal stability catalyst to form a second catalyst layer, and forming a catalytic reaction structure with an activity gradient along an airflow direction; the catalytic reaction structure with the activity gradient is integrated in a modular shell.

The invention provides a silicon-carbon negative electrode material utilizing atomic layer deposition and a preparation method thereof, and the method adopts an atomic layer deposition method to deposit a silicon negative electrode active layer on a carbon carrier to prepare the silicon-carbon negative electrode material. The deposition temperature of the atomic layer deposition silicon negative electrode active layer is less than or equal to 400 DEG C. The carbon carrier is graphite, carbon black, activated carbon, mesoporous carbon, carbon nanotubes, graphene, graphdiyne or carbon aerogel. The precursor of the atomic layer deposition silicon negative electrode active layer is silane and halogenated silane. Silane and halogenated silane are used as precursors, atomic-scale precise construction of a silicon-carbon negative electrode is realized through an ALD process, and the silicon-carbon negative electrode material not only can effectively relieve volume expansion of the silicon negative electrode material, but also can shorten the transportation distance of lithium ions and improve the cycle performance of the battery.

The invention belongs to a lithium ion battery negative electrode material, and particularly relates to a porous carbon matrix for a silicon-carbon negative electrode and a preparation method of the porous carbon matrix. The specific surface area of the porous carbon material is not less than 1800m < 2 > / g, and the pore volume is not less than 0.9 cm < 3 > / g; and the mechanical strength is 10-17 MPa. According to the ordered mesoporous carbon matrix prepared by adopting a soft template method, pores of the material are generated from inside to outside, the pore distribution is uniform, the particle consistency is high, the pores are highly ordered and through cubic mesopores, and the pore diameter is about 5nm. After simple activation treatment, the specific surface area and micropore channels of the material can be effectively improved, and the material is suitable for being used as a base material of chemical vapor deposition silicon. In addition, the carbon material has a high-strength carbon skeleton, the particle strength is high, and an effective confinement effect can be provided to maintain the volume integrity of the silicon particles. The prepared silicon-carbon negative electrode material has higher particle capacity, more stable cycle performance and better rate capability, and meanwhile, the process steps are simple and efficient.

Herein is described a composite material, the composite material comprising composite 5 particles comprising particles of a mesoporous carbon support material having dispersed on their surfaces noble metal nanoparticles and / or noble metal-M alloy nanoparticles and optionally particles of the elemental metal M or metal oxide MOy, wherein y is >0 to a stoichiometric value of the metal oxide, wherein M is a less noble metal than the noble metal, wherein the composite particles have a BJH average pore diameter of from 2 to 0 50 nm and a particle size D90, as measured by laser diffraction and volume distribution, of 10 µm or less.

The invention belongs to the technical field of lithium ion batteries, and particularly relates to a dry battery pole piece, a preparation method thereof and a battery comprising the pole piece, and the method comprises the following steps: S1, preparing a composite current collector; s2, preparing an electrode film: S21, preparing a positive electrode film, and S22, preparing a negative electrode film; s3, preparing a pole piece green body: sequentially laminating the positive electrode film, the composite current collector and the negative electrode film, and carrying out gradient pressure rolling at 120-180 DEG C, linearly increasing the pressure from 5-10MPa at the edge to 15-20MPa at the center, and controlling the rolling speed to be 1-3m / min, so as to form the pole piece green body; and S4, preparing the dry-method battery pole piece. The composite current collector adopts a three-layer substrate structure of a metal substrate layer, mesoporous carbon, an MOF composite transition layer and a conductive polymer transition layer, gradient pores are formed through laser drilling, and an AlO nano coating is deposited to enhance interface bonding.

The invention belongs to the technical field of preparation of methyl tetrahydrophthalic anhydride, and particularly relates to a methyl tetrahydrophthalic anhydride isomerization catalyst and a preparation method thereof. The catalyst provided by the invention adopts a three-layer core-shell structure, and magnetic separation and recovery are realized by a magnetic Fe3O4-coated SiO2 / Al2O3 core layer; the alkaline middle layer of the mesoporous carbon loaded nano MgO is isolated by a PDMS hydrophobic layer; and the zirconium-based MOF acidic shell layer contains a sulfonic acid group and tungsten oxide. An Al2O3 protective layer and a tungsten oxide Lewis acid site are constructed through an atomic layer deposition technology, and coexistence of acid-base active sites is realized by combining PDMS interface isolation. The catalyst provided by the invention solves the problem of separation of a traditional homogeneous catalyst, synergistically regulates and controls the structure / stereoisomerization reaction, the product purity reaches 99% or above, and the catalyst is suitable for industrial continuous production.

The invention relates to a preparation method of a silicon-carbon negative electrode material, the silicon-carbon negative electrode material and application of the silicon-carbon negative electrode material, the preparation method comprises the following steps: firstly, circularly depositing on the outer surface of micro-mesoporous carbon and the surface of a pore wall through an atomic layer deposition method to form a multi-layer oxide monomolecular isolation layer and a multi-layer oxide monomolecular functional layer, and then carrying out silicon deposition and carbon coating treatment to obtain the silicon-carbon negative electrode material. The silicon-carbon negative electrode material is obtained; the multi-layer oxide monomolecular isolation layer of the silicon-carbon negative electrode material can effectively block the reaction between a carbon source and active silicon and inhibit the generation of silicon carbide side reaction, and the multi-layer oxide monomolecular functional layer can reduce the migration barrier of lithium ions and improve the ionic conductivity, so that the silicon-carbon negative electrode material can be applied to the lithium ion battery, and the service life of the lithium ion battery is prolonged. And the first-cycle coulombic efficiency and the cycle capacity retention ratio of the lithium ion battery can be effectively improved.

The invention relates to a preparation method of a bio-based mesoporous carbon material, and belongs to the technical field of carbon material preparation. The invention provides a preparation method of a bio-based mesoporous carbon material, and the bio-based mesoporous carbon material is prepared by taking agricultural and forestry wastes as raw materials through three steps of pretreatment, phosphoric acid activation and polyaniline-graphene quantum dot compounding. In the pretreatment stage, the raw materials are crushed, soaked in an ethanol-acetone mixed solution at 40-80 DEG C for 2-6 h and dried, and powder B is obtained; in the phosphoric acid activation stage, a 50-80% phosphoric acid solution is used for dipping for 12-48 hours according to the mass ratio of 1: (2-5), and carbonization is performed under the protection of 400-700 DEG C nitrogen to obtain a solid product In the compounding stage, D is dispersed in a 0.1-1 mol / L aniline hydrochloric acid solution, after polymerization is initiated by ammonium persulfate, 0.01-0.1 g / L graphene quantum dot solution is added for compounding, and after centrifugal drying, the high-performance carbon material with the specific surface area larger than or equal to 1800 m < 2 > / g, the proportion of 2-5 nm holes larger than 35% and the mesoporous rate larger than 75% is prepared, and the high-performance carbon material is suitable for the field of supercapacitors.

The invention relates to a uniform carbon-coated mesoporous silicon carbon negative electrode material and a preparation method and application thereof.The preparation method comprises the steps that a product obtained after pyrolysis and carbonization of a biomass carbon source is subjected to alkali activation treatment, acid pickling, drying, smashing, passivation, water washing and drying are conducted to obtain a mesoporous carbon matrix, nanometer silicon particles are deposited in pores of the mesoporous carbon matrix, and the uniform carbon-coated mesoporous silicon carbon negative electrode material is obtained. Then selecting a low-temperature carbonization material and polyethylene glycol to perform pre-carbonization and complete carbonization treatment on the mesoporous silicon carbon material to obtain a carbon coating layer, and finally obtaining the uniform carbon-coated mesoporous silicon carbon negative electrode material. When the uniform carbon-coated mesoporous silicon carbon negative electrode material is applied to a lithium battery, the mesoporous skeleton can effectively inhibit volume expansion of silicon in a battery circulation process, and the uniform carbon-coated layer can effectively reduce the risk of direct contact between the negative electrode material and an electrolyte, so that a stable SE I film is formed to reduce the occurrence of side reactions; and the first coulombic efficiency and the cycle performance of the battery are further improved.