93 results about "Nitrogen doped" patented technology

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 provides a preparation method of a gate oxide layer and a gate, and the method comprises the steps: carrying out the rapid thermal annealing treatment of a silicon-based substrate in a nitrogen-containing gas atmosphere, which belongs to a non-destructive nitrogen doping mode, and carrying out the nitrogen pre-doping on the surface of the silicon-based substrate, so as to reduce the doping amount needed by the subsequent plasma nitrogen doping; therefore, the damage of the plasma nitrogen doping process to the SiON gate oxide layer is reduced, and the interface defect between the SiON gate oxide layer and the silicon-based substrate interface is reduced. Besides, after the nitrogen pre-doped layer is formed, the thermal oxidation process is carried out on the silicon-based substrate to form the silicon dioxide gate oxide layer, so that the damage to the SiON gate oxide layer film is reduced, and the interface defect between the SiON gate oxide layer and the silicon-based substrate interface is further reduced; moreover, the laser rapid annealing treatment can remove the intrinsic oxide layer on the surface of the SiON gate oxide layer, repair the damage to the crystal lattice of the SiON gate oxide layer caused by the plasma nitrogen doping treatment process, improve the film quality and repair the interface.

The invention relates to the technical field of acid tail gas treatment, and discloses a boron-nitrogen-doped aluminum oxide catalyst as well as a preparation method and application thereof. The method comprises the following steps: (1) mixing an aluminum source, a nitrogen source, a boron source and water to obtain a mixed solution, then adding a peptizing agent to adjust the pH of the mixed solution to be acidic, and then standing and aging; (2) drying the material subjected to standing and aging in the step (1), then roasting under protective gas, and then sequentially carrying out high-temperature nitriding and cooling; and (3) carrying out plasma treatment on the material cooled in the step (2). The catalyst prepared by the method has large specific surface area and catalytic activity, can well capture water and carbonyl sulfide, converts carbonyl sulfide into hydrogen sulfide and improves the purity and yield of enriched hydrogen sulfide, and the preparation method of the catalyst is simple and efficient.

The present application relates to a kind of for metallurgical coal gas to remove organic sulfur nitrogen-doped catalyst and its preparation method and application, including the following steps: with soluble aluminum salt as carrier, it is prepared with certain proportion of nitrogen source compound mixed solution, then precipitate completely in alkaline environment, after stirring, aging, drying treatment, with high temperature calcination nitrogen-doped Al2O3 catalyst is obtained.The catalyst has more nitrogen site, stronger nitrogen doping capacity, so that the basic center of catalyst increases, improves the catalytic activity when catalytic elimination carbonyl sulfur, while reducing the adsorption of H2S, improves H2S yield, reduces the formation of sulfur, ensures the activity and stability of catalyst, prolongs the life of catalyst.

The present invention relates to the technical field of nanopowder preparation, and discloses a method for preparing a nitrogen-doped biochar-loaded iron nitride composite material. The process is as follows: (1) potassium ferrate, urea, and waste tea powder are ground and mixed in proportion to obtain a first mixture; (2) the first mixture is reacted in a temperature range of 50-70°C to obtain a second mixture; (3) the second mixture is reacted in a temperature range of 600-800°C for 1-3 hours, and then cooled to room temperature to obtain a third mixture; (4) the third mixture is washed and dried to obtain a nitrogen-doped biochar-loaded iron nitride composite material. Compared with the existing preparation process, the beneficial effect of the present invention is that the operation steps only include grinding, stirring, heating, etc., the operation is simpler, the overall process only involves one pyrolysis, the energy consumption is lower, and the toxic gas ammonia is not used, and the operation is safer. The material can degrade trichloroethylene without an anaerobic environment and can be used for the remediation of organochlorine-contaminated groundwater environment.

This invention discloses a two-step method for preparing nitrogen-doped three-dimensional network phenolic resin-based composite carbon materials and their applications. The method uses an alkaline environment provided by ammonia to induce addition condensation polymerization of phenol and formaldehyde to obtain a preliminary nitrogen-doped phenolic resin. This resin is then mixed with melamine resin to achieve a second step of nitrogen introduction, and after being composited with sodium alginate, it is cross-linked with CaCl2 to obtain a three-dimensional hydrogel precursor. After carbonization and activation treatment, a nitrogen-doped porous carbon material is obtained. This material possesses both micro- and mesoporous synergy and multiple types of nitrogen functional sites, exhibiting high specific surface area capacitance and excellent cycling stability in supercapacitors. Compared with existing schemes that only use NaOH without introducing dual-source nitrogen doping (such as CN119724955A), this invention achieves synergistic optimization of structure, chemical sites, and transport through ammonia pre-doping, secondary nitrogen doping with melamine resin, and a ternary interpenetrating network. The process is simple, uses inexpensive raw materials, and is suitable for large-scale production.

The invention discloses a preparation method and application of a cobalt-nitrogen-doped mesoporous carbon catalyst, and belongs to the technical field of catalyst preparation, and the preparation method comprises the following steps: mixing and grinding glucose and an SBA-15 mesoporous molecular sieve, pyrolyzing in a nitrogen atmosphere, soaking the obtained product in hydrofluoric acid to remove an SBA-15 template, alternately centrifuging with water and ethanol to obtain a precipitate, and drying to obtain the cobalt-nitrogen-doped mesoporous carbon catalyst. Mesoporous carbon is obtained; the preparation method comprises the following steps: respectively dissolving phenanthroline and cobalt chloride hexahydrate in ethanol, and mixing to form a Co-phen solution; and soaking the obtained mesoporous carbon in a Co-phen solution, evaporating the solvent after soaking, grinding into powder, and carrying out heat treatment in a nitrogen atmosphere to obtain the cobalt-nitrogen doped mesoporous carbon catalyst. The cobalt-nitrogen-doped mesoporous carbon catalyst shows excellent oxygen reduction catalytic activity under the alkaline condition, the half-wave potential reaches 0.873 V and is close to a 4-electron transfer path, and the stability and methanol tolerance are superior to those of a commercial Pt / C catalyst.

The present application relates to the technical field of carbon nanotubes and provides nitrogen-doped carbon nanotubes and a preparation method thereof, wherein the preparation method of the nitrogen-doped carbon nanotubes comprises the following steps: providing a lamellar catalyst with a metal carrier; reducing and activating the lamellar catalyst to obtain an activated catalyst; introducing an atmosphere of a carbon source and a nitrogen source into the activated catalyst to react and obtain nitrogen-doped carbon nanotubes. The preparation method of the present application provides a lamellar catalyst with a metal carrier, wherein the catalytically active component (metal) of the lamellar catalyst has a strong adsorption capacity on the carrier and an ion exchange capacity with the carrier, making it easier for the catalytically active component elements to enter the mesopores and micropores on the inner surface of the lamellar carrier material, better utilizing the surface area of ​​the carrier, achieving uniform dispersion of the catalytically active elements, and improving the loading amount and uniformity of the lamellar catalyst with the metal carrier; the preparation method is suitable for fluidized bed production processes and can be used for industrial production.

The invention belongs to the field of environmental protection and air purification, and particularly relates to a nitrogen-doped titanium dioxide loaded copper nanoparticle photocatalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: synthesizing an N-TiO2 carrier through a low-temperature hydrolysis method, and loading Cu NPs on the N-TiO2 carrier through a wet impregnation method to prepare the Cu / N-TiO2 catalyst. The Cu / N-TiO2 photocatalyst obtained by the invention can effectively catalyze and remove NO and CO under the conditions of 120-210 DEG C and visible light, and has good stability and NH3 selectivity. Compared with an N-TiO2 carrier, the performance of removing NO and CO through photocatalysis and the NH3 selectivity are obviously improved. The high-cost limitation of a traditional noble metal catalyst is broken through, an innovative solution is provided for low-temperature photo-thermal synergistic purification of motor vehicle exhaust, and application and popularization are facilitated.

Nitrogen doping an insulating layer can lower the bandgap of a magnetic storage device. It is challenging to nitrogen dope magnesium oxide (MgO). A cation can be added to allow the magnesium to hold onto the nitrogen dopant without highly oxidizing or nitriding the cation. The resulting nitrogen doped MgXO, where X is the cation, has a lower bandgap compared to a much similar barrier layer that has neither nitrogen nor a cation thus improving thermal and electrical reliabilities. The nitrogen doped MgXO is non-stoichiometric whereas comparably, an oxynitride is stoichiometric. Example cations that may be used include aluminum, titanium, vanadium, chromium, and scandium.

The invention provides a boron-nitrogen doped resin coated graphite material and a preparation method thereof, a battery negative electrode and a lithium ion battery, and the method comprises the following steps: mixing graphite and a boron doping agent, and presintering to obtain boron-doped graphite; mixing the boron-doped graphite with resin and a nitrogen doping agent to obtain composite particles, and then roasting the composite particles to obtain the boron-nitrogen-doped resin coated graphite material, the mass ratio of the graphite to the boron doping agent is 10: (0.1-2), and the mass ratio of the boron-doped graphite to the nitrogen doping agent to the resin is 10: (0.1-2): (0.1-2). The graphite-resin material with a core-shell structure is prepared by performing boron doping on the graphite material and then coating the resin doped with the nitrogen element, the loss of the graphite material caused by lithium intercalation and deintercalation is effectively inhibited by the structure, the cycle life of the material is prolonged, meanwhile, the strength of the material is also improved by boron doping, and the service life of the material is prolonged. And the cycle life and the capacity of the material are greatly improved.

This application applies to the field of new energy materials technology, providing hard carbon anode materials and their preparation methods, nitrogen-containing asphalt coatings, and sodium-ion batteries. The method includes: nitrogen-doping asphalt to obtain nitrogen-containing asphalt coatings; uniformly mixing pre-carbonized biomass powder with the nitrogen-containing asphalt coatings; and sintering the resulting mixed powder to obtain the hard carbon anode material. By doping the asphalt with nitrogen, the asphalt exhibits a larger carbon interlayer spacing after high-temperature sintering, providing sodium storage sites and facilitating rapid sodium ion migration. This improves the material's initial charge-discharge efficiency and hydrophobicity without affecting specific capacity and rate performance. Furthermore, the pre-carbonization of biomass allows for the uniform adsorption of small coating particles onto the main material. The highly graphitized coating layer formed during high-temperature sintering exhibits stronger hydrophobicity and fewer defect sites, transforming the open-pore structure into a closed-pore structure, thereby improving its initial charge-discharge efficiency, specific capacity, and cycle performance as a sodium battery anode.

The invention discloses nitrogen and phosphorus doped activated carbon loaded zero-valent iron, a preparation method thereof and an antibiotic-containing wastewater treatment method. The preparation method of the nitrogen and phosphorus doped activated carbon loaded zero-valent iron comprises the following steps: step a, treating activated carbon with hydrochloric acid to obtain activated carbon powder; step b, adding activated carbon powder into a K3PO4 solution, performing ultrasonic treatment to obtain activated carbon impregnated with K3PO4, heating the activated carbon impregnated with K3PO4 to obtain phosphorus-doped activated carbon, impregnating the phosphorus-doped activated carbon into an ammonia water solution, heating, stirring and standing to obtain nitrogen-phosphorus-doped activated carbon; and step c, adding the phosphorus-nitrogen doped activated carbon and polyethylene glycol into the FeSO4. 7H2O solution, and dropwise adding sodium borohydride to obtain the nitrogen-doped activated carbon loaded zero-valent iron powder. Nitrogen and phosphorus doped activated carbon loaded zero-valent iron adopted by the invention generates potential difference between low-valence zero-valent iron and high-valence activated carbon in a substrate with a large amount of electrolyte to form a primary battery, and generated electrons, [H] with strong oxidizing property and the like have a promoting effect on anaerobic digestion.

The application discloses a kind of adsorbents for noble metal recovery and preparation method thereof, further provide a kind to be used in the noble metal recovery method of the catalyst, wherein the adsorbents for noble metal recovery includes nitrogen-doped graphene-SiO2 Hybrid Material, the nitrogen-doped graphene-SiO2 Hybrid Material includes graphene-SiO2 Hybrid Material and nitrogen doped therein, wherein the molar amount of nitrogen in the nitrogen-doped graphene-SiO2 Hybrid Material and the total molar amount of C and Si are 1: (55-10050) ratio. The noble metal recovery adsorbent of the application can effectively recover noble metal Au in wastewater, has strong noble metal recovery adsorption capacity, high recovery rate, especially for the catalyst washing produced in the preparation process of vinyl acetate catalyst containing lower content of noble metal element Au has higher noble metal recovery adsorption capacity.

The invention discloses a tubular confinement structure CoFe diatomic nitrogen-doped carbon-based catalyst for removing new pollutant wastewater and a preparation method. A transition metal diatomic nitrogen-doped carbon-based catalyst with a tubular nano confinement structure is generated in situ through simple high-temperature calcination. The prepared CoFe-CNT / PANI catalyst has a large specific surface area and a tubular nano confinement structure, the specific surface area can reach 200-300 m < 2 > / g, the size of the tubular structure is about 5-10 [mu] m, and the thickness of the tube wall is 3-5 nm. The synergistic effect of the transition metal diatomic active sites and the tubular nano confinement structure can effectively improve the generation and utilization efficiency of active species, promote mass transfer and enhance stability. By constructing a CoFe-CNT / PANI electro-catalysis system, more than 94% of new pollutants such as ibuprofen and the like can be efficiently removed within 60 minutes. The operation steps are simple, the cost is low, the problems that a traditional catalyst is low in activity, slow in reaction mass transfer, low in utilization rate and the like are solved, and an efficient, rapid and stable technical scheme is provided for treatment of new pollutant wastewater in the technical field of electrochemistry and environmental remediation.

The application discloses a polypyrrone-derived carbon-coated metal catalyst and a preparation and application thereof. The catalyst prepared by the application provides a nitrogen-doped carbon layer by polypyrrone, which not only provides protection for an active center, but also promotes electron transmission between carbon layers by the conductive property of the polypyrrone-derived carbon layer itself. The polypyrrone-derived carbon-coated metal catalyst is applied to a catalytic hydrogenation reaction of chloronitrobenzene containing sulfur-containing poisons, and shows excellent activity, selectivity and stability.

The invention provides a composite hard carbon negative electrode material, a preparation method thereof and a battery, and the preparation method comprises the following steps: mixing asphalt and ion exchange resin to obtain a first precursor; performing carbonization treatment on the first precursor to obtain a second precursor; performing nitrogen doping treatment on the second precursor to obtain a third precursor; and performing plasma treatment on the third precursor to obtain the composite hard carbon negative electrode material, the battery comprises the composite hard carbon negative electrode material obtained by the method. The contradiction between the raw material cost and the performance consistency in the prior art is solved, the problem of balance between electronic conductivity and ion transmission is solved, and the problems that dead holes or closed holes exist in the surface of a traditional hard carbon material and cannot be effectively infiltrated by electrolyte, and the contact resistance is large due to particle aggregation are solved.

The application discloses a boron and nitrogen doped carbon loaded copper catalyst and a preparation method and application thereof. The catalyst is prepared by the following steps: treating carbon with excessive concentrated nitric acid, impregnating the treated carbon and copper nitrate at room temperature, grinding the obtained precursor and a nitrogen source and a boron source into powder at room temperature, and calcining the powder at a specific temperature and for a specific time. The catalyst can be applied to electrocatalytic reduction of carbon dioxide to oxygen-containing products. The catalyst mainly induces stronger metal-carbon support interaction by B and N co-doped carbon, improves the average valence state of copper to promote the CO-CO coupling route, effectively stabilizes oxygen-containing intermediates in the reaction process due to the relatively strong oxygen affinity of B, and inhibits the breaking of C-O bonds, so that high activity and high selectivity of ethanol are realized. The catalyst has excellent performance in the reduction of carbon dioxide to ethanol.

Embodiments of the present disclosure generally relate to methods of producing carbon-nitrogen allotrope nanomaterials. More specifically, the methods of the present disclosure utilize nitrogen-containing compounds as a feedstock for nitrogen doped carbon nanomaterial production. In some embodiments, a method for forming carbon-nitrogen nanomaterials includes mixing a nitrogen-rich feedstock, carbon-based feedstock, and a catalyst to form a feed solution. The method further includes injecting the feed solution into a carrier gas stream and into a heated reaction vessel. The heated reaction vessel includes a first zone and a second zone. The method further includes heating the feed solution within the first zone at a first temperature. The method further includes heating the feed solution within the second zone at a second temperature to form the carbon-nitrogen nanomaterials. The method further includes removing the carbon-nitrogen nanomaterials from the heated reaction vessel.

The invention relates to the technical field of polyaryletherketone modification, in particular to a hydrophobic high-CTI (comparative tracking index) polyaryletherketone composite material which is formed by melting, blending and compounding a material A and a material B, the material A comprises polyaryletherketone and polyether acrylate fluoride; the material B is a graft of nitrogen-doped aluminum borate modified by an amino silane coupling agent and a glycidyl acrylate compound; the composite material has hydrophobicity, the CTI value is at least 340 V, the water absorption rate is low, and the composite material can be suitable for a high-humidity environment.

Semiconductor devices including a nitrogen-doped field release dielectric layer (130) are described. A microelectronic device (100) comprises: a substrate (103) comprising a body region (108) having a first conductivity type and a drain drift region (138) having a second conductivity type opposite the first conductivity type; a gate dielectric layer (150) on the substrate (103), the gate dielectric layer (150) extending over the body region (108) and the drain drift region (138); and a nitrogen doped field release dielectric layer (130) on the drain drift region (138).

The application provides preparation and application of a sulfur-nitrogen doped single-atom cobalt loaded porous carbon sulfur composite positive electrode material. The sulfur-nitrogen doped single-atom cobalt loaded porous carbon is obtained through high-temperature pyrolysis of the interaction among cobalt ions, dopamine and thiourea, the electronic structure of the active site of the catalyst is adjusted through common doping of sulfur and nitrogen, the catalytic activity of the single-atom cobalt is improved, the physical adsorption of the porous hollow carbon and the catalytic effect of the single-atom cobalt are synergistically exerted through the coordination between the porous carbon substrate and the single atom, the dissolution of polysulfides is greatly reduced, and the cycle stability of the battery is improved.

The invention provides a preparation method of a graphene and ferric oxide composite nanomaterial and a derivative thereof. Comprising the following steps: preparing a graphene and ferric oxide composite nano material (GF), preparing a graphene and ferric oxide composite nano material (HGF) pre-oxidized by hydrogen peroxide, and preparing a nitrogen-doped graphene and ferric oxide composite material (N-GF). According to the preparation method of the ferric oxide composite nano-material, provided by the invention, the ferric oxide nano-particles are uniformly anchored on the graphene nano-sheets through processes of one-step water bath synthesis, pre-oxidation, nitrogen doping and the like to form a rich pore structure, so that more active sites and a relatively large sodium storage space can be provided; meanwhile, the electron transmission path is shortened.

The invention discloses hydrogen storage biochar and a preparation method and application thereof.The preparation method of the hydrogen storage biochar comprises the steps that a biomass precursor is taken and subjected to air carbonization, and an air carbonization precursor is obtained; uniformly mixing the air carbonization precursor and KOH according to a ratio, raising the temperature in a nitrogen atmosphere, and naturally cooling to room temperature; dispersing the obtained product in deionized water, and adding a nitrogen-calcium doping agent; adding the obtained mixed solution into a hydrothermal reaction kettle for reaction, and cleaning and drying a product to obtain the hydrogen storage biochar. The activation resistance of the biomass to KOH is improved through the first-step air atmosphere pre-carbonization process, meanwhile, the nitrogen doping process is optimized, anchor point N elements and Ca elements are loaded through a hydrothermal method, an N doping agent is used as an anchor point, Ca loading is promoted, the reaction condition is mild, the structure of the raw material is not damaged, and the hydrogen storage performance of the biochar is remarkably improved.

The application relates to a method for preparing nitrogen-doped hollow hierarchical porous carbon spheres based on a silane coupling agent and belongs to the field of environmental protection. The method combines a soft template and a hard template and is assisted by physical activation, N-(2-aminoethyl)-3-aminopropyl trimethoxysilane is introduced into the system as a structure directing agent, a pore forming agent and a nitrogen source, and nitrogen-doped hollow hierarchical porous carbon spheres are prepared in one step. The specific surface area of the prepared material is as high as 1716.75 m 2 / g. The N-(2-aminoethyl)-3-aminopropyl trimethoxysilane can not only serve as a nitrogen source, but also promote the formation of pores in the process of synthesizing the carbon material. The adsorption amount of CO2 can reach 5.11 mmol / g under the conditions of 0 DEG C and 1 bar. The method has the advantages of simple process, low energy consumption, easy modification, high raw material utilization rate, easy availability, easy industrial application, etc. The prepared carbon material has great application potential in carbon dioxide capture before and after combustion.

The present invention relates to a sulfur-nitrogen doped MXene hydrogen storage material catalyst, a hydrogen storage material containing the catalyst and a preparation method thereof, and belongs to the field of hydrogen storage technology. The hydrogen storage material catalyst is sulfur-nitrogen doped Nb2CT x The hydrogen storage catalyst was ball-milled with magnesium hydride to produce a composite hydrogen storage material. This catalyst exhibits excellent catalytic activity in the absorption and desorption processes of magnesium hydride. In hydrogen desorption kinetics testing, the composite hydrogen storage material produced using this catalyst and magnesium hydride released 5.32 wt.% of hydrogen within 5 minutes at 275°C, and absorbed 5.08 wt.% of hydrogen within 2 minutes at 150°C. Furthermore, the initial desorption temperature of this composite hydrogen storage material was 105.48°C lower than that of pure magnesium hydride. The catalyst preparation method is simple, and the raw materials are readily available, making it suitable for scale-up production.

Nitrogen-doped CZ silicon crystal ingots and wafers sliced therefrom are disclosed that provide for post epitaxial thermally treated wafers having oxygen precipitate density and size that are substantially uniformly distributed radially and exhibit the lack of a significant edge effect. Methods for producing such CZ silicon crystal ingots are also provided by controlling the pull rate from molten silicon, the temperature gradient and the nitrogen concentration. Methods for simulating the radial bulk micro defect size distribution, radial bulk micro defect density distribution and oxygen precipitation density distribution of post epitaxial thermally treated wafers sliced from nitrogen-doped CZ silicon crystals are also provided.

A functional polycrystalline silicon tunneling silicon oxide passivated contact structure (TOPCon) and a preparation method thereof are provided. The functional polycrystalline silicon tunneling silicon oxide passivated contact structure includes a crystalline silicon substrate, a nano silicon oxide, and a functional polycrystalline silicon structure laminated in sequence. The functional polycrystalline silicon structure includes a carbon and nitrogen co-doped polycrystalline silicon layer, or alternating layers of a carbon-doped polycrystalline silicon layer and a nitrogen-doped polycrystalline silicon layer. The present invention uses doping engineering to prepare new polycrystalline silicon with different functions, namely, carbon-doped polycrystalline silicon, nitrogen-doped polycrystalline silicon, and carbon and nitrogen co-doped polycrystalline silicon, and forms a functional polycrystalline silicon structure, exerting different functional effects of carbon and nitrogen doped atoms, and simultaneously realizing passivation in the bulk and surface of the silicon wafer, thereby obtaining a TOPCon structure with ultra-high passivation performance.

The invention discloses a simple and low-cost method for preparing nitrogen (iron)-doped three-dimensional porous graphene, which comprises the following steps: by taking typha angustifolia leaves as a carbon precursor and ferric ammonium citrate as a nitrogen source and a graphitization catalyst, carrying out microwave heating pore-forming, carbonization and graphitization to obtain the nitrogen (iron)-doped three-dimensional porous graphene. The nitrogen content, the iron content, the specific surface area and the graphite degree of the material can be controlled according to the use amount of the ammonium ferric citrate and the microwave time. The material is metal-free nitrogen-doped three-dimensional porous graphene after iron removal.

The present application relates to the technical field of composite materials, and particularly relates to a nitrogen-doped carbon quantum dot composite film and a preparation method thereof.A specific technical scheme is as follows: a preparation method of a nitrogen-doped carbon quantum dot composite film, comprising the following steps: (1) using polyethylene polyamine as a nitrogen source combined with a carbon source to perform a hydrothermal reaction, and completing preparation of carbon quantum dots; (2) adding 1-(3-dimethylaminopropyl)-3-ethyl carbodiimide and N-hydroxysuccinimide or N-hydroxylthiosuccinimide into a hydrophilic modified polymer composite film to perform a reaction, and after the reaction is completed, a nitrogen-doped carbon dot modified composite film is obtained, and the nitrogen-doped carbon dot modified composite film is stored by being immersed in water.The nitrogen-doping design makes the nitrogen-doped carbon dot composite film have a good effect in capturing and enriching persistent organic pollutants such as perfluorinated compounds, and has good application value for treatment of new pollutants in the environment.