58results about How to "Good mesoporous structure" patented technology

The invention provides a cobalt selenide / nitrogen-doped carbon composite material and a preparation method and an application therefor, and belongs to the technical fields of nanomaterial preparation and application. An organic metallic framework ZIF-67 is taken as a template for preparing the cobalt selenide / nitrogen-doped carbon composite material; the material adopts a rhombic dodecahedron shape with controllable sizes; and cobalt selenide is cobalt selenide or cobalt diselenide nanoparticles uniformly dispersed on a nitrogen-doped carbon framework. The compound has a good mesoporous structure and excellent conductivity; and when the composite material is used as the electrode material for a supercapacitor, a high specific capacitance and high stability are achieved.

The invention discloses a preparation method of ellipsoidal nitrogen-doped mesoporous carbon. Ellipsoidal mesoporous silica is taken as a hard template, an organic high-molecular polymer is taken as a carbon source, a precursor containing nitrogen is taken as a nitrogen source, and ethanol is taken as a solvent. The preparation method comprises following steps: full immersing of the carbon source and the nitrogen source into the pores of ellipsoidal mesoporous silica is realized by stirring, and ellipsoidal mesoporous silica is dried after complete volatilization of ethanol so as to obtain nitrogen-doped ellipsoidal mesoporous carbon; in nitrogen atmosphere, nitrogen-doped ellipsoidal mesoporous carbon is heated to 600 DEG C at a heating rate of 1 DEG C / min, and is calcined for 2h, and then nitrogen-doped ellipsoidal mesoporous carbon is heated to 700 to 1000 DEG C at a heating rate of 2 DEG C / min, and is calcined for 2h so as to obtain an ellipsoidal mesoporous carbon / silica composite material; and then the ellipsoidal mesoporous carbon / silica composite material is stirred in an acid solution for 2h, and is centrifuged, washed and washed so as to obtain ellipsoidal nitrogen-doped mesoporous carbon. Stacking density of ellipsoidal nitrogen-doped mesoporous carbon is relatively high, and the mesoporous structure is orderly, so that ellipsoidal nitrogen-doped mesoporous carbon can be used as an electrode material for preparation of supercapacitors.

The invention relates to a preparation method of mesoporous silica fluorescent nanoparticles for pH ratio probes, which comprises the following steps of: firstly adopting silane coupling agents for carrying out pre-modification on a binary fluorescence resonance energy transfer dye; then, by using a sol-gel chemical principle and the self assembling behavior of silicon materials and surface active agents used as structural guide agents in solution, obtaining the spherical mesoporous silica fluorescent nanoparticles through the co-hydrolyzation fasculation between the silane coupling agents and silicon source precursors. Compared with the prior art, the preparation method has the advantages that the obtained mesoporous silica fluorescent nanoparticles have the single-wavelength exciting pHratio fluorescent probe function, the pH detection limit and the detection range can be regulated and controlled through changing the proportion among the binary fluorescence resonance energy transfer dyes, and in addition, guest molecules can be loaded at high capacitance because the system has good mesoporous structures and biocompatibility.

The invention discloses a method for preparing a Schiff base functionalized ordered mesoporous PMO material solid supported Cu(I) heterogeneous catalyst and application thereof in a Glaser organic reaction in an aqueous medium. The method comprises the following steps of: mixing 0.90 to 1.2g of amino-functionalized PMO with 15 to 25ml of ethanol and 0.8 to 1.2 mmol of 2-pyridylaldehyde solution; stirring the mixture for 12 to 18 hours at room temperature; then filtering and washing the mixture, performing vacuum drying and standing overnight to obtain an ordered mesoporous Schiff base functionalized PMO (Et); adding 0.40 to 0.60g of Schiff base-PMO (Et) into 12 to 18 ml of dimethyl sulfoxide solution which contains 0.1 to 0.3 mmol of CuI; stirring the mixture for 24 to 36 hours at the room temperature; filtering the solids and washing the solids by using the dimethyl sulfoxide and ethanol in turn; and finally performing vacuum drying on the product and standing overnight so as to obtain an ordered mesoporous organic metal copper heterogeneous catalyst. The catalyst has the advantages of organic group content, higher hydrophobic property, easy diffusion of an organic reactant in a pore channel, well contact with a catalytic active site, improvement of catalytic efficiency, ordered mesoporous structure, uniform pore diameter distribution, and large specific surface area.

A method for preparing an ellipsoidal nitrogen-boron-phosphorus-doped mesoporous carbon uses ellipsoidal mesoporous silica as a hard template, an organic macromolecule polymer as a carbon source, a nitrogen-containing precursor as a nitrogen source, a boron-containing precursor as a boron source, a phosphorus-containing precursor as a phosphorus source, and ethyl alcohol or deionized water as a solvent, by stirring, the precursors are fully immersed in a pore channel of the ellipsoidal mesoporous silica, and drying is performed after the solvent volatilizes completely, thereby obtaining the ellipsoidal nitrogen-boron-phosphorus-doped mesoporous carbon; then in nitrogen atmosphere, the ellipsoidal nitrogen-boron-phosphorus-doped mesoporous carbon is heated at a heating rate of 1 DEG C / min, and is calcined, and then is heated at a heating rate of 2 DEG C / min, and is calcined, thereby obtaining an ellipsoidal mesoporous carbon / silica compound; and finally the ellipsoidal mesoporous carbon / silica compound is stirred in an acid solution, and is centrifuged, washed and dried, thereby obtaining ellipsoidal nitrogen-boron-phosphorus-doped mesoporous carbon. Stacking density of the ellipsoidal nitrogen-boron-phosphorus-doped mesoporous carbon that is obtained is relatively high, and the mesoporous structure is orderly, so that the ellipsoidal nitrogen-boron-phosphorus-doped mesoporous carbon can be used as an electrode material for manufacture of a supercapacitor.

The invention discloses clubbed phosphor-doped mesoporous carbon as well as a preparation method and an application thereof. The clubbed phosphor-doped mesoporous carbon is of a mesoporous structure; in terms of atomic percent, the clubbed phosphor-doped mesoporous carbon comprises 0.51-0.66% of phosphor element and the balance of carbon; and the aperture distribution of the clubbed phosphor-doped mesoporous carbon is 1.57-2.04nm, the specific surface area is 942-1513m<2> / g and the pore volume is 0.85-1.18cm<3> / g. The preparation method comprises the following steps: mixing clubbed mesoporous silicon dioxide, an organic high-molecular polymer, a phosphor-containing precursor and ethyl alcohol; stirring to ensure that the carbon source and the phosphor source are sufficiently dipped into the pore passage of the mesoporous silicon dioxide; after the ethyl alcohol fully volatilizes, drying to obtain a phosphor source / carbon source / silicon dioxide compound; carrying out high-temperature carbonization to obtain a clubbed phosphor-doped mesoporous carbon / silicon dioxide compound; putting the clubbed phosphor-doped mesoporous carbon / silicon dioxide compound in a hydrofluoric acid water solution to remove the silicon dioxide; and drying to obtain the clubbed phosphor-doped mesoporous carbon which is used for preparing electrode materials for super capacitors.

The invention relates to a supported iron-based Fischer-Tropsch catalyst. The supported iron-based Fischer-Tropsch catalyst contains a spherical mesoporous carbon support, an active component iron located on the support and an optional catalyst promoter, wherein the specific surface area of the spherical mesoporous carbon support is 500-1000 m<2> / g, pore volume is 1.5-3.5 cm<3> / g, and average porediameter is 9-30 nm. According to the catalyst, spherical mesoporous carbon with high pore volume and large pore diameter is taken as the support, not only can high loading capacity of iron be realized, but also when the prepared catalyst is applied to the Fischer-Tropsch reaction, high Fischer-Tropsch reactivity and high productivity can be obtained, and particularly, CO conversion rate is remarkably increased and hydrocarbon productivity is improved. The invention further relates to preparation of the catalyst and an application of the catalyst to the Fischer-Tropsch reaction.

The invention provides a ceramic power composition, which comprises 55-95% of alumina and further comprises one or more the following components: 5-35% of feldspar powder, 5-35% of kaolin, 5-25% of zirconia, 1-10% of titanium oxide and 0.5-5% of calcium oxide. The invention further provides ceramic slurry, a ceramic catalyst carrier prepared from the slurry and application of the carrier and the catalyst in a high-viscosity reaction system. The invention overcomes the defects of poor stability, serious inactivation phenomenon, low reaction conversion rate and the like of the traditional catalyst in the reaction of the high-viscosity system, the aperture ratio of the ceramic catalyst carrier is greatly improved compared with the prior art and can even reach a millimeter scale, and meanwhile, the ceramic catalyst carrier can be maintained with higher specific surface area inside, has the properties of uniform pore opening, high porosity, heat and shock resistance, high-temperature resistance and chemical corrosion resistance, as well as excellent mechanical strength and adsorption property, can be maintained with high stability in a reaction process, can improve the conversion rate in the reaction, and is particularly suitable for the high-viscosity reaction system.

The invention relates to a catalyst carrier prepared from mixed aluminum oxide and mesoporous molecular sieve and a preparation method thereof. The mixed mesoporous carrier is prepared by the following steps of: adding the mesoporous molecular sieve and various auxiliary agent into a conventional aluminum oxide source; performing mixing and extrusion moulding; and then performing hydrothermal treatment, drying and roasting to finally obtain a finished product dehydrogenation catalyst carrier. The prepared light alkane dehydrogenation catalyst carrier has high mechanical strength, good thermal stability and enhanced catalysis activity.

The present invention discloses a method for preparing a high hydrothermal stability mesoporous molecular sieve by adopting an acid functionalized ion liquid as a medium and adopting a non-ionic surfactant or an ionic surfactant as a template agent. The preparation method comprises: sequentially adding sodium meta-aluminate, silica hydrosol (30%), sodium silicate and an acid functionalized ion liquid to a reaction kettle, uniformly mixing at a room temperature in the reaction kettle, transferring the mixed material to an autoclave, carrying out crystallization for 4-6 hours at a temperature of 120-140 DEG C, cooling to a room temperature after completing the reaction, adding an acid functionalized ion liquid and a template agent to the solution after the reaction, stirring for 20-24 hours at a temperature of 40-60 DEG to obtain a homogeneous phase gel mixture, transferring the gel mixture to the autoclave, carrying out crystallization for 24-48 hours at a temperature of 100-120 DEG C, cooling, adding deionized water to dilute and wash, carrying out suction filtration, and carrying out drying calcination to obtain the mesoporous molecular sieve product. The mesoporous molecular sieve prepared by the preparation method has good hydrothermal stability while the ion liquid can be recycled. The synthesis method has advantages of simpleness and environmental friendliness, and has important application values in the field of material science.

The invention discloses a zirconium-containing polyborosilazane precursor aerogel, a silicon-boron-carbon-nitrogen / zirconium dioxide ceramic aerogel, and a preparation method and application of the ceramic aerogel. Through combination of a silicon-hydrogen addition reaction and CO2 supercritical drying, the highly porous zirconium-containing PBSN precursor ceramic aerogel is prepared by taking polyborosilazane and ZBO as precursors; and then the SiBCN-ZrO2 ceramic aerogel is synthesized by a conventional precursor conversion method. The microstructure and physical properties of the obtained samples are characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and X-ray diffraction (XRD), and the results show that the formation temperature and themaximum crystallization transition temperature of an SiBCN matrix are improved through addition of zirconium. The zirconium-containing precursor aerogel and the SiBCN-ZrO2 ceramic aerogel both have relatively good mesoporous structures. Meanwhile, the specific surface area, the pore volume and the average pore diameter of the SiBCN-ZrO2 ceramic aerogel are respectively 98.1204 m<2>g<-1>, 0.4832 cm<3>g<-1> and 14.47 nm at a temperature of 1350 DEG C, and the sintered ceramic aerogel mainly consists of ZrO2, beta-SiC and Si3N4 crystalline phases and an SiBCN amorphous phase.

The invention belongs to the technical field of catalyst materials, and discloses a supported catalyst with a kernel-shell structure, a preparation method thereof and an application. The preparation method of the catalyst includes: co-precipitating alcoholic solution of base metal soluble salt and carrier metal soluble salt under the function of precipitator; and then sintering and restoring sediment, and obtaining the precursor of the supported base metal; and then performing replacement reaction and sintering reaction twice on the supported base metal precursor and precious metal homogeneous solution, and obtaining the supported catalyst taking mesoporous metal oxide as a carrier, base metal as kernel, and alloy of the base metal and precious metal as a shell. The catalyst forms the supported kernel-shell structure, the shell is an alloy of the thin base metal and the precious metal; thus the dosage of the precious metal can be obviously reduced, the production cost of catalyst is decreased; during the catalyzing, decomposing and hydrogen-making processes of hydrazine hydrate, the supported catalyst has good catalyzing efficiency and hydrogen-making selectivity.

The invention discloses a ceramic filter element added with carbon nano tubes. The ceramic filter element added with the carbon nano tubes is characterized by being prepared from the following raw materials in parts by weight: 15-17 parts of activated carbon, 10-13 parts of diatomite, 6-9 parts of cordierite, 2-3 parts of carbon nano tube, 3-5 parts of smashed cotton exocarp, 6-8 parts of smashed coconut shell, 7-9 parts of mica powder, 5-8 parts of clay, 8-10 parts of aluminium powder, 4-6 parts of zeolite, 1-2 parts of chitosan, 5-7 parts of modified coconut shell activated carbon and a defined amount of water. The ceramic filter element added with the carbon nano tubes is added with chitosan, so that the ceramic filter element added with the carbon nano tubes has good clarification and flocculation effects; the carbon nano tubes are added, so that the mechanical properties of the ceramic filter element can be improved; a mesoporous structure is formed, so that heavy metal ions in water can be effectively adsorbed and removed; modified coconut shell activated carbon is added, so that interspace is developed, the adsorption property is good, the strength is high, and the ceramic filter element added with the carbon nano tubes can be regenerated easily and is economical and durable; the purification efficiency is high, the service life is long, and the corrosion resistance is high, so that the ceramic filter element added with the carbon nano tubes can be used for air adsorption filtration or inspiration filtration by virtue of a car filter cleaner.

The invention belongs to the technical field of material preparation, and particularly relates to a phosphorus-containing mesoporous carbon material, a method for preparing the same and application ofthe phosphorus-containing mesoporous carbon material. The method includes dissolving nonionic surfactants in organic solvents to obtain solution; adding soluble resin and phosphorus-containing precursors into the solution; inducing multi-element organic assembling by the aid of solvent evaporation to obtain phosphorus-containing resin-surfactant composite materials; carbonizing the phosphorus-containing resin-surfactant composite materials at the high temperatures to obtain the phosphorus-containing mesoporous carbon material. The phosphorus content of the phosphorus-containing mesoporous carbon material prepared by the aid of the method is 0.3-7.0 wt%, the pore diameters of the phosphorus-containing mesoporous carbon material are 3.0-15 nm, the pore volumes of the phosphorus-containing mesoporous carbon material are 0.2-0.6 cm<3> / g, and the specific surface areas of the phosphorus-containing mesoporous carbon material is 290-890 m<2> / g. The phosphorus-containing mesoporous carbon material and the method have the advantages that the novel phosphorus-containing mesoporous carbon material is excellent in performance in the aspect of electrode materials for lithium-ion batteries, andthe capacity can keep at 500 mAh / g after 200 cycles under the condition of the current density of 0.5 C; the phosphorus-containing mesoporous carbon material and the method hopefully can be extensively applied to the aspects of sodium-ion batteries, electro-catalysis and the like.

The invention relates to a preparation method of single-crystal mesoporous Mo3N2 for a positive electrode material of a lithium-sulfur battery, wherein the preparation method comprises the steps: preparing a single-crystal MoO3 nanowire by a hydrothermal method, and preparing a single-crystal mesoporous Mo3N2 nanostructure with high specific surface area by a topological reaction method by using the single-crystal MoO3 nanowire as a starting material. Molybdenum nitride has a large number of pores, the sulfur loading capacity is improved, and the shuttle effect is inhibited. The molybdenum nitride effectively solves the problem of the volume expansion effect of the lithium-sulfur battery while significantly improving the sulfur loading capacity of the positive electrode material. Non-toxicreactants and a hydrothermal method and a topological reaction method which are simple to operate are adopted, and non-toxic and harmless sublimed sulfur powder is loaded for preparing the positive electrode material of the lithium-sulfur battery, so that the method has remarkable advantages in the aspects of environmental protection, industrial production, products and application.

The invention relates to a method for preparing an Ag-AgBr / Al-MCM-41 composite functional material from natural attapulgite. The method includes steps: taking the natural clay mineral attapulgite as a raw material, and soaking in organic acid to obtain acidized attapulgite; taking the acidized attapulgite as a raw material, well mixing with NaOH solid, and performing high-temperature roasting for activation; adding deionized water into the activated attapulgite, and taking upper leachate for standby application; adding the leachate into surfactant solution, introducing AgNO3 into synthesized mother solution by means of in-situ assembly to generate AgBr precipitate, carrying out a hydrothermal process, and calcining a synthesized product to obtain the composite functional material. The method has advantages that raw materials are cheap and easy to acquire, and a preparation process is simple and feasible; by in-situ assembly, one-step completion of synthesis and functionalization of a mesoporous material can be realized, solvent utilization in a conventional aftertreatment method and procedures of repeated calcination are avoided, time saving and energy saving are realized, and environment pollution is avoided.

The present invention discloses a method for preparing a mesoporous molecular sieve-loading Cu-Ni bimetallic catalyst, and aims at the defect of a catalyst for preparation process of 1,2-propanediol by glycerol hydrogenolysis, ionic liquid 1-cetyl-3-methyl bromo-imidazole is used as a template agent, and two metal elements Cu and Ni are added into the ion thermal synthesis process of the catalyst. Compared with immersion method in the prior art, the metal loading process is simple. The catalyst exhibits good thermal stability and strong acid sites, and exhibits high reactivity in the course of preparation of 1,2-propanediol from glycerol, glycerol conversion rate is more than 70%, and 1,2-propanediol selectivity is above 50%.

The invention discloses an electrochemical method for preparing a mesoporous tungsten trioxide film. The method comprises the steps that metal tungsten subjected to pretreatment is taken as an anode,a titanium sheet or a platinum sheet serves as a cathode, in an electrolyte, constant-potential anodic oxidation is performed for 1-7 hours under the condition that the temperature ranges from 5 DEG Cto 40 DEG C and the voltage ranges from 3 V to 15 V, and then the metal tungsten is taken out to be cleaned and dried to obtain the mesoporous tungsten trioxide film on the surface of the metal tungsten. According to the electrochemical method, the tungsten trioxide films with different pore diameters can be obtained on the surface of the metal tungsten by controlling the electrolyte component, the anodic oxidation voltage and the oxidation time; the prepared tungsten trioxide film has a remarkable mesoporous structure, the specific surface area is large, and the prepared tungsten trioxide film is firmly combined with a metal tungsten substrate and is not prone to fall off; and the electrochemical method is simple in preparation process, low in cost, simple and convenient to operate, highin efficiency and wide in application prospect in the aspect of industrial application.

The invention aims to overcome the defects of poor hydrophobic modification effect, easiness in causing mesoporous structure damages during high-temperature treatment, and the like existing in the conventional method, and provides a sol-gel production process for preparing a hydrophobic mesoporous silicon dioxide film. The process has the advantages of simple experimental equipment, convenience for operating, ready availability of raw materials, low energy consumption, low cost, and industrial popularization and practical application values. The mesoporous silicon dioxide film disclosed by the invention has a good mesoporous structure and high hydrophobicity. The average pore diameter of the obtained hydrophobic mesoporous silicon dioxide film is 8 nanometers, the pore volume is 0.8g / cm<-3>, and the contact angle is up to 115 degrees. The improvement on the hydrophobicity of the mesoporous silicon dioxide film is an effective means for improving the performance, popularizing and applying.

The invention discloses a preparation method of an expandable graphite hard polyurethane composite thermal insulation material. The preparation method comprises the following steps of: S1, preparing SiO2 aerogel; and S2-S5, preparing rigid polyurethane foam plastic, so as to obtain the aerogel-expandable graphite rigid polyurethane composite thermal insulation material. According to the expandable graphite hard polyurethane composite thermal insulation material and the preparation method thereof, the hard polyurethane composite thermal insulation material with a lower heat conductivity coefficient is obtained, meanwhile, the cost of raw materials is reduced, and the production period is shortened.

The invention provides a solvent-free and kilogram-scale preparation method for regular mesoporous phenol-formaldehyde resin. A phenolic organic compound and an aldehyde organic compound are adopted as the raw materials, a block copolymer is taken as the template, and a simple, fast and solvent-free one-step synthesis method is utilized to realize amplified preparation of mesoporous phenol-formaldehyde resin. At the same time, by optimizing the experimental parameters, laboratory gram-scale preparation is successfully expanded to kilogram-scale material preparation, and the prepared material maintains a highly regular mesoporous structure and the doping of nitrogen heteroatoms. By optimizing the structural parameters of the material, the amplification prepared material in the invention shows excellent adsorption performance (a hydrogen sulfide adsorption capacity up to 3.2-5.3mmol / g under a 0DEG C condition) in hydrogen sulfide gas adsorption performance test. The method provided by the invention is of important practical significance for realizing green and large-scale preparation of regular mesoporous phenol-formaldehyde resin and application of the resin to selective desorptionof hydrogen sulfide.

The invention innovatively provides a preparation method of a formed nitrogen-containing mesoporous carbon material capable of being industrially produced in a large scale. The method comprises the following steps: taking melamine resin as a carbon source and a nitrogen source and magnesium citrate as a template agent, mixing the melamine resin, the magnesium citrate and sodium alginate to form a colloidal solution by means of the gelling property of the sodium alginate, performing wrapping forming through a ball dropping method to form melamine resin gel balls with rigid shells, and performing drying, roasting at high temperature and pickling to obtain the novel formed nitrogen-containing mesoporous carbon material. Research results show that: the carbon material has a very high specific surface area, a prominent mesoporous structure and a relatively large average pore size, has abundant nitrogen atoms and oxygen atoms, also has good mechanical strength, is an excellent noble metal catalyst carrier, shows relatively good unsaturated fatty acid C=C double-bond hydrogenation activity on a fixed bed reactor, and has good market application prospects.

The invention discloses a preparation method of a magnetoplumbite type CH4-CO2 reforming catalyst. According to the preparation method, alkaline sodium aluminate NaAlO2 is taken as an aluminum source, nickel nitrate Ni (NO3)2 is taken as a nickel source, strontium nitrate Sr (NO3)2 is taken as a strontium source, a nickel strontium aluminate precipitation copolymer is obtained with an ultrasonic copolymerization method, a hydrothermal reaction is performed for 16-20 h at the temperature of 160-180 DEG C, a pre-crystallization body with a magnetoplumbite structure is prepared, finally, crystallization sintering is performed for 6-8 h at the lower temperature of 750-850 DEG C, and a magnetoplumbite-structured SrNiAl11O19 reforming catalyst material with higher purity and good crystallization condition can be prepared.

The invention relates to a method for preparing an automatic humidity control material from calcium chloride, and belongs to the technical field of preparation of indoor functional decorative materials of buildings. The method comprises the steps as follows: waste glass and limestone are crushed, sieved by a 100-mesh sieve and dried; 20%-90% by mass of waste glass and 10%-80% by mass of limestoneare weighed, 85%-99% by mass of limestone and 1%-15% by mass of calcium chloride are weighed, and finally, water or a sodium hydroxide solution accounting for 5%-10% of the total weight of waste glass, limestone and calcium chloride is weighed, wherein the concentration of the sodium hydroxide solution is 2-5 mol / L; after all the raw materials are uniformly mixed, the mixture is pressed into a block sample under molding pressure of 10-30 MPa and demoulded, hydrothermal curing is performed for 1-24 h at temperature of 140-200 DEG C, and the block cured product prepared after drying is a high-strength automatic humidity control building material. The method adopts a simple process and is energy-saving and environmentally friendly, and the obtained product has superior moisture absorption anddesorption performance, which far exceeds the national standard requirements of JC / T 2082-2011 indoor decorative building materials with the function of humidity-control.

The invention provides application of a transition metallic composite oxide catalyst in catalytic oxidation of methylbenzene to synthesize benzyl benzoate. The application is characterized in that thecatalyst adopts a metallic composite oxide as a carrier, a high-activity transition metallic salt is adopted as a catalytic oxidation activity center, a halide is adopted as a catalysis assisting activity center, and the halide is selected from one or two of halides containing elements of F, Cl, Br and I. The catalyst provided by the invention is of a good mesoporous structure at a high temperature, is capable of catalyzing methylbenzene to selectively oxidize and synthesize benzyl benzoate under a gentle reaction condition, has very high selectivity and activity in reactions, and has multiple advantages of being simple in preparation process, low in cost, free of environment pollution, easy to separate, good in repeatability, and the like.

The invention relates to the technical field of material science, and provides mesoporous calcium carbonate nanoparticles, a preparation method thereof and a composite material. The calcium carbonate nano-particle is formed by compounding amorphous calcium carbonate and calcium carbonate crystal grains, the calcium carbonate nano-particle has a mesoporous structure, and the mesoporous size is 2-50 nm. The preparation method of the calcium carbonate nanoparticles comprises the following steps: completely dissolving a calcium chloride donor in an organic solvent, then adding an etching agent, and uniformly mixing to obtain a solution I1; putting the open container filled with the I1 into a closed container filled with ammonium bicarbonate, enabling the ammonium bicarbonate to be excessive in the reaction process, and standing to react for 3-10 days to obtain a reactant I2; and sequentially centrifuging, washing and drying the I2 to obtain a product I3. The calcium carbonate nanoparticles are mixed with a polymer to prepare a high-strength and high-toughness composite material.

The invention discloses application of a magnetic carboxylated covalent organic framework material as a magnetic solid-phase extraction adsorbent, and a preparation method of the material comprises the following steps: (1) firstly, by taking dopamine hydrochloride as a coordination stabilizer, synthesizing surface aminated magnetic iron oxide particles from ferric chloride and ferrous chloride through a coprecipitation method; and (2) activating the surface-aminated magnetic iron oxide particles, and carrying out covalent crosslinking on the surfaces of the aminated magnetic iron oxide particles through a solvothermal method under the reversible catalytic action of acetic acid by taking trialdehyde phloroglucinol and 4, 4-diaminobiphenyl-2, 2-dicarboxylic acid as construction units, so as to prepare the magnetic carboxylated covalent organic framework material. The carboxylated covalent organic framework material prepared by the method has a relatively large specific surface area and a good mesoporous structure, is stable in structure, large in adsorption capacity and short in equilibrium time and has multiple adsorption acting forces, so that the steps of sample pretreatment are greatly simplified, and the sample treatment time is shortened.