14 results about "Nitrogen doped graphene" patented technology

The application discloses a kind of methods for constructing electrochemical immunosensor for detecting apolipoprotein A4, comprising: (1) nitrogen-doped graphene and polyethyleneimine are fully stirred in solvent Composite, then add bipyridine functionalized covalent organic framework material and fully stir Composite, obtain NG-PEI-COF composite material;With bipyridine functionalized covalent organic framework material as carrier, gold nanoparticles, apolipoprotein A4 antibody and toluidine blue are loaded in sequence, to obtain tracer probe;(2) on electrode NG-PEI-COF composite material, gold nanoparticles, apolipoprotein A4 and tracer probe are modified in sequence, to obtain the electrochemical immunosensor of the application.The electrochemical immunosensor constructed by the method shows excellent detection performance for apolipoprotein A4, the marker of depression, good reproducibility and stability, and shows good anti-interference performance for a variety of other markers of depression, can be accurately determined in 0.01~300 ng / mL linear range, detection limit is as low as 2.16 pg / mL, and can be applied to serum sample.

The present invention provides a nitrogen-doped graphene acid that is present in a sample and contains 3 at.% to 10 at.% (preferably 4 at.% to 6 at.%) of nitrogen and 25 at.% to 45 at.% (preferably 30 to 38 at.%) of oxygen for all atoms determined by X-ray photoelectron spectroscopy (XPS) using an Al-Kα X-ray source. In some embodiments, the nitrogen-doped graphene acid is in the form of dots. The nitrogen-doped graphene acid is produced by a method comprising the following steps: supplying nitrogen-doped graphene, oxidizing the nitrogen-doped graphene by reaction with an oxidizing inorganic acid, preferably nitric acid, and washing the resulting mixture with water. The nitrogen-doped graphene acid is for the isolation of Pb 2+ and / or Cd 2+ , or for the detection of Pb 2+ and / or Cd 2+ and is particularly useful.

This invention relates to the field of biosensor technology, and in particular to an electrochemiluminescence sensor, its fabrication method, and its applications. The sensor comprises a three-electrode system, wherein the working electrode includes a substrate electrode, an amino-functionalized vertically ordered mesoporous silica film formed on the surface of the substrate electrode, and nitrogen-doped graphene quantum dots confined within the amino-functionalized vertically ordered mesoporous silica film; the electrolyte used in the sensor is a phosphate buffer containing luminol. This invention achieves highly sensitive and selective detection of superoxide dismutase (SOD) by constructing an electrode modified with nitrogen-doped graphene quantum dots confined within an amino-functionalized vertically ordered mesoporous silica film, utilizing its enhanced luminol-dissolved oxygen electrochemiluminescence signal and the specific quenching effect of SOD on superoxide anions.

The application provides a preparation method of a nitrogen-doped graphene CIGS thin-film battery tail gas purifying agent, and is characterized in that the method comprises the following steps: S1, placing a nitrogen-doped graphene carrier and a composite copper source in a reaction kettle, adding ammonia water, stirring for 20-40 min, and obtaining a reaction product for standby; S2, adding a strong alkali solution into the reaction product in step S1, stirring for 20-30 min, washing, suction filtering, and drying to obtain the nitrogen-doped graphene CIGS thin-film battery tail gas purifying agent. The tail gas purifying agent has the characteristics of removing H2S and H2Se gas at room temperature, can be widely applied to the field of environmental protection material preparation, and has good commercial application value.

The application discloses a high-thermal-conductivity modified polyurethane pouring sealant and a preparation method thereof, and relates to the technical field of adhesives. The application comprises the following raw materials in parts by mass: modified polyurethane prepolymer 265-318 parts, silane coupling agent KH-550 5-6 parts, modified composite filler 80-96 parts, ethylene glycol amine 3.2-3.7 parts, and dibutyltin dilaurate 0.3-0.36 parts. The modified composite filler is prepared from the silane coupling agent KH-550, graphene, silicon carbide, boron nitride nanosheet, cellulose nanofiber and modified nitrogen-doped graphene. The modified nitrogen-doped graphene is prepared from nitrogen-doped graphene powder, calcium nitrate tetrahydrate and diammonium hydrogen phosphate. The application effectively improves the thermal conductivity, mechanical properties, moisture and heat aging resistance and high-temperature resistance of the high-thermal-conductivity polyurethane pouring sealant by introducing the modified polyurethane prepolymer and the modified nitrogen-doped graphene.

The application belongs to the technical field of composite electrode materials, and relates to a preparation method of a ternary CoS / NiCoAl-LDH / NGQDs heterostructure electrode material and application thereof. First, carbon cloth is immersed in a solution containing cobalt ions and 2-methyl imidazole, so that a cobalt-based metal organic framework (Co-MOF) array is grown in situ on the carbon cloth substrate. Then, through hydrothermal sulfidation treatment, the Co-MOF precursor is converted into hollow cobalt sulfide (CoS) nanotubes. Second, a nickel-cobalt-aluminum layered double hydroxide (NiCoAl-LDH) nanosheet is uniformly deposited on the surface of the CoS nanotube by electrodeposition, so as to form a hierarchical core-shell structure. Finally, nitrogen-doped graphene quantum dots (NGQDs) are anchored on the surface of the composite material through electrostatic adsorption, so as to complete the construction of the ternary heterostructure. The core advantage of the application lies in the directional construction of a synergistic interface, and each component solves different key problems: CoS provides a stable conductive network, NiCoAl-LDH endows multiple-electron redox reaction activity, and NGQDs improve the interface stability and charge injection efficiency.

The present application belongs to the field of nanometer carbon material preparation, discloses a kind of carbon quantum dots and preparation method thereof prepared by waste recovery, suitable for UV curing coating application, aims at solving the problems such as poor batch consistency of carbon dots prepared from waste and insufficient compatibility with coating, realizes the high value closed loop of electrochemical aluminum / transfer film waste coating waste material.The present application uses the waste coating waste material containing nitrogen polymer in the industry as raw material, after pre-classification and alkali alcohol mixed solvent pretreatment, hydrothermal carbonization and purification, surface modification is completed by UV photochemical grafting specific UV curing monomer, and 2-10nm nitrogen-doped graphene quantum dot powder is prepared;The process parameters such as hydrothermal and grafting are optimized, to realize the covalent bonding of carbon quantum dots and UV curing coating.The raw material of the present application is green and low cost, the batch consistency of the product is significantly improved, the compatibility and storage stability of the coating are greatly improved, and after adding, the fluorescence anti-counterfeiting and curing tracing of UV curing coating can be realized, which meets the requirements of double carbon target and new material industry development.

The invention discloses a binder-free transition metal sulfide composite nitrogen-doped graphene negative electrode material and a preparation method thereof, and belongs to the technical field of secondary battery negative electrode materials. According to the technical scheme, the preparation method comprises the following steps: 1) dissolving zinc nitrate, cobalt nitrate and nitrogen-doped graphene in a mixed solution of ethanol and water, uniformly mixing, adding ammonium fluoride and urea, and continuously stirring; 2) adding foamed nickel and the uniformly mixed solution into a high-pressure reaction kettle for hydrothermal treatment, cooling, washing and drying to obtain a Zn-Co-precursor; (3) calcining the Zn-Co-precursor in an inert atmosphere, and (4) adding the Zn-Co-precursor into a high-pressure reaction kettle containing a sulfur source for hydrothermal vulcanization treatment, washing and drying to obtain the ZnCo2S4-coated NGr / NF negative electrode material.The graphene negative electrode material can improve the overall performance and stability of a secondary battery.

The present application relates to the technical field of conductive silver paste, and particularly relates to an improved conductive silver paste and a preparation method thereof.The conventional conductive silver paste has poor conductivity and high volume resistivity.In view of the above problems, the present application provides an improved conductive silver paste, which simultaneously adds cellulose nanocrystal modified silver-coated copper powder and conductive polymer modified nitrogen-doped graphene in the formula.The conductive polymer modified nitrogen-doped graphene and the cellulose nanocrystal on the surface of the modified silver-coated copper powder and the epoxy resin matrix produce better strong interaction, forming a continuous'silver-coated copper powder-conductive polymer-graphene' three-dimensional conductive network, which significantly reduces the volume resistivity of the overall conductive silver paste and improves the stability of the conductive path.

This invention relates to the field of catalysts for the hydrogenation of nitrobenzene to aniline, specifically disclosing a magnetically separable carbon-supported platinum cluster catalyst, its preparation method, and its applications. The magnetically separable carbon-supported platinum cluster catalyst comprises platinum nanoparticles as the active component and a nickel-coated nitrogen-doped graphene composite material as the support. The nickel-coated nitrogen-doped graphene composite material has a core-shell structure, with platinum nanoparticles uniformly loaded in clusters on the surface of the nitrogen-doped graphene, bonding with carbon and nitrogen atoms on graphene defects. The high utilization rate of platinum atoms enables efficient hydrogenation of nitrobenzene even at low loading levels, while also making the catalyst structure more stable. The support surface has abundant carbon defects and oxygen-containing functional groups, which facilitates the anchoring of platinum nanoparticles to the support surface through strong interactions between the metal and the support. The magnetic nickel nanoparticles impart a certain degree of magnetism to the catalyst, allowing for dispersion and recovery of the catalyst simply by removing and applying a magnetic field.

The application relates to the technical field of heavy metal ion detection, in particular to a nitrogen-doped graphene modified paper-based electrode and a preparation method and application thereof. The preparation method provided by the application comprises the following steps: providing filter paper, the filter paper has a hydrophobic region and a non-hydrophobic region, and the surface of the hydrophobic region is provided with a hydrophobic barrier; printing a three-electrode system and a conductive pad on the surface of the filter paper to obtain a paper-based electrode, the three-electrode system comprises a working electrode, a counter electrode and a reference electrode; mixing an ammonium chloride and ammonia water mixed solution and an oxidized graphene solution to obtain an electrolyte; and dropping the electrolyte on the paper-based electrode to perform electrochemical deposition, thereby obtaining a nitrogen-doped graphene modified paper-based electrode. The preparation method is simple in operation and mild in conditions, and the nitrogen-doped graphene electrode prepared by the method has strong anti-interference performance, low detection limit and high sensitivity when simultaneously detecting Cd 2+ , Pb 2+ and Hg 2+ three ions in a water environment.

The application discloses a graphene membrane with adsorption-electrocatalysis-membrane separation triple functions and a preparation method and application thereof, the graphene membrane comprises a base film, a reduced graphene oxide rGO base layer loaded on the surface of the base film, and a cationic polyamine layer and an M-NG catalyst layer alternately assembled on the surface of the base layer in sequence, the number of layers of the cationic polyamine layer assembled on the surface of the base layer of the base film is recorded as m, the number of layers of the M-NG catalyst layer assembled on the surface of the base layer of the base film is m or m-1, m is an integer of 7-12; the M-NG catalyst comprises nitrogen-doped graphene NG and metal M monomers loaded on the nitrogen-doped graphene NG, the metal M is one of Co, Ni and Fe, and the loading amount of the metal M on the M-NG catalyst is 0.5-3%. The membrane material disclosed by the application is suitable for efficient removal of refractory organic pollutants (such as perfluorinated compounds) in the water treatment process, and has a wide application prospect.

The application discloses a preparation method and application of a boron-nitrogen co-doped gradient graphene-coated capacitor carbon composite electrode material, and the boron-nitrogen doped graphene coating layer is formed on the capacitor carbon particles by controlling pyrolysis conditions, the graphene is graphene oxide, the boron-containing reducing agent is a reducing agent containing boron, and the nitrogen source is a nitrogen source, and a multi-stage pore structure of micropores-mesopores-macropores which is beneficial to the rapid transmission of ions is simultaneously constructed, so that the pore channel is avoided from being blocked due to coating, the specific capacity of the electrode is improved, the conductivity and the electrochemical activity are improved, and the interface wettability of the electrode and the electrolyte is optimized, the formed electrode material has the function of double inhibition of electrolyte side reactions, and is suitable for application in the fields of supercapacitors and the like.

This invention discloses a membrane electrode assembly based on a three-dimensional nitrogen-doped graphene aerogel support and its preparation method, as well as a hydrogen fuel cell. The assembly includes a composite proton exchange membrane, an anode catalyst layer and a cathode catalyst layer coated on both sides of the composite proton exchange membrane, an anode gas diffusion layer located outside the anode catalyst layer, and a cathode gas diffusion layer located outside the cathode catalyst layer. Both the anode and cathode catalyst layers contain catalysts, and the catalyst support is a three-dimensional nitrogen-doped graphene aerogel. The composite proton exchange membrane is a perfluorosulfonic acid resin-based composite membrane containing sulfonated graphene oxide. This application uses a three-dimensional nitrogen-doped graphene aerogel as the catalyst support, and the resulting macroscopic three-dimensional network effectively prevents the stacking of graphene sheets. The composite proton exchange membrane has abundant sulfonic acid groups, which significantly improves the durability in accelerated aging tests and enhances the operational stability in low-humidity environments while maintaining high power density in the hydrogen fuel cell.