165results about How to "Excellent electron transfer ability" patented technology

The invention provides a graphene loaded high-dispersion nano Ni catalyst as well as a preparation method and application thereof. The catalyst is obtained by loading high-dispersion Ni nano-metal on the surface of graphene, and doping less amorphous Al2O3, wherein the mass percent content of graphene is 40-67%, the mass percent content of Ni is 10-40%, the mass percent content of amorphous Al2O3 is 2-8%, the size distribution of Ni particles is 8-13nm, and the specific area of the catalyst is 155-200 m<2> / g. The preparation method comprises the following steps of: preparing a graphene / lamellar bimetal hydroxide composite material in one step through the hydroxide precipitation and reduction effect, and then preparing the graphene loaded high-dispersion metal Ni nano catalyst through an in-situ self-reduction method by using the reducibility of graphene. The catalyst is used for selectively hydrogenating the cinnamyl aldehyde to synthesize the benzenepropanal, and the conversion rate and the benzenepropanal selectivity are respectively 86-100% and 88-96%.

The invention belongs to the field of anticorrosive coating, and in particular, relates to a graphene / deimpurity polyaniline-containing anticorrosive coating. The anticorrosive coating is composed of the following raw materials in parts by weight: 20-80% of epoxy resin, 5-15% of a graphene / deimpurity polyanilin composite material, 5-10% of a zinc powder, 5-10% of a filler, 1-10% of a coloring pigment, 0.1-3% of a dispersion agent, 0.1-3% of a wetting agent, 0.1-3% of a thickening agent, 0.1-1% of a levelling agent, 0.1-1% of a defoaming agent, 0.1-1% of a bactericide, and 1-35% of water. In the preparation process of the anticorrosive coating, polyaniline is loaded on graphene by an in-situ polymerization method, so that the dispersion of polyaniline is improved, polyaniline agglomeration is avoided, and the graphene / deimpurity polyaniline-containing anticorrosive coating is prepared.

The invention discloses a modified-electrode-based tyrosinase biosensor comprising a glassy carbon electrode, wherein nanogold particles are deposited on the surface of a detection end of the glassy carbon electrode; an L-lysine film is adsorbed on the outer surfaces of nanogold particles; ordered mesoporous carbon supported nanogold is loaded outside the L-lysine film; and tyrosinase is adsorbed on the ordered mesoporous carbon supported nanogold. The preparation method comprises the following steps of: firstly preparing suspension liquid of the ordered mesoporous carbon supported nanogold, depositing the nanogold particles on the glassy carbon electrode by using an electrochemical method, immersing the detection end of the nanogold modified electrode in an L-lysine solution, forming a layer of L-lysine film on the outer surface of each nanogold particle by using the electrochemical method, dropwise adding the suspension liquid of the ordered mesoporous carbon supported nanogold to the surface of the detection end, drying, and dropwise adding a tyrosinase solution in air and so as to obtain the tyrosinase biosensor. The tyrosinase biosensor disclosed by the invention has the advantages of low cost, simpleness in manufacturing, long service life, high enzyme activity, high detection precision and efficiency and the like.

The invention provides a biosensor for detecting silver as well as a preparation method and application thereof. The biosensor comprises a glassy carbon electrode which is used as a working electrode in a three-electrode system; the surface of a reaction end of the glassy carbon electrode is modified with a gold nano-cluster; the surface of the metal nano-cluster is modified with ordered mesoporous carbon; the surface of the ordered mesoporous carbon is modified with a nanogold layer; the surface of the nanogold layer is self-assembled with a C1 probe which is capable of forming a double chain in a C-Ag-C mispairing manner. The preparation method comprises the steps of modifying with the gold nano-cluster, modifying with ordered mesoporous carbon, carrying out electro-deposition on nanogold and assembling the C1 probe. The application method comprises the steps of firstly establishing the three-electrode system, putting a glassy carbon electrode reaction end of the biosensor in a solution to be detected for reacting for 2h and measuring the concentration of silver ions in the solution to be detected according to the change of the concentration and resistance difference of silver ions. The biosensor provided by the invention has the advantages that the manufacture is simple, the service life is long, the anti-jamming capability is high, the detection precision and efficiency are high, etc.

The invention discloses a mercuric ion or cysteine detecting electrochemical DNA biosensor and a manufacturing method and application thereof.The electrochemical DNA biosensor comprises a glassy carbon electrode serving as a working electrode of a three-electrode system; the surface of a reactive end of the glassy carbon electrode is modified by composite membrane composed of auto-doped polyaniline nanofiber, ordered mesoporous carbon and nano-scale gold particles; a DNA capture probe, with the nucleotide sequence SEQ ID NO.1 is assembled on the surface of the composite membrane.The manufacturing method includes steps of modifying auto-doped polyaniline nanofiber and ordered mesoporous carbon, electrodepositing nano-scale gold particles, assembling the DNA capture probe and the like.The mercuric ion or cysteine detecting electrochemical DNA biosensor capable of detecting two different target substances has the advantages of high stability, long service life, high interference resistance capacity, wide detection scope and low limit in detection and is applied to detection of mercuric ion or cysteine.

The invention relates to the technical field of denitration, in particular to a selective catalytic reduction denitration catalyst, a preparation method and application thereof. The catalyst is prepared from a carrier, transition metal oxide loaded on the carrier, and a rare earth modification additive, as well as a rare earth metal polymer distributed on the carrier as a porous mesh metal frame structure, wherein the total load capacity of the transition metal oxide, the rare earth modification additive and the rare earth polymer on the carrier is 25-35%. The catalyst disclosed by the invention is excellent in catalytic activity at a temperature interval from 200 DEG C to 400 DEG C; the denitration conversion ratio can be up to 90% above; meanwhile, the trace of rare earth modification additive is added to the catalytic system to effectively improve the sintering resistance of the catalyst; the catalyst can effectively improve the lead and sulfur toxic resistance of the catalyst, widens the low temperature reaction window, and prolongs the service life of the catalyst.

The invention discloses a preparation method of a collagen fiber immobilized tannin loaded nanometer zero-valent Fe-Ni bimetallic ball adsorption reduction material, which comprises the following steps: adding ultrapure water into collagen fibers, soaking overnight, adding tannin, stirring, filtering, dispersing in a crosslinking agent solution, regulating the pH value, crosslinking, filtering, washing, and drying to obtain a collagen fiber cured tannin material; dispersing the collagen fiber cured tannin material in water, adding a Fe < 3 + > solution or a Fe < 2 + > solution, adjusting the pH value, stirring and reacting to obtain a mixed solution, adding a Ni < 2 + > solution into the mixed solution, adjusting the pH value, continuously reacting, filtering and washing; re-dispersing theobtained material in a reducing agent solution, reducing at normal temperature, filtering, washing, repeatedly dehydrating with ethanol, and drying in vacuum to obtain the collagen fiber immobilizedtannin loaded nanometer zero-valent Fe-Ni bimetallic ball adsorption reduction material; the material can be applied to adsorption and separation of various heavy metals, and has ultrahigh adsorptioncapacity for certain metal ions.

The invention belongs to the technical field of electrochemical biosensors and particularly relates to an enzyme biosensor for detecting cholesterol as well as a preparation method and an application of the biosensor. The enzyme biosensor adopts a classical three-electrode system, wherein a specific matter recognizing enzyme membrane is solidified on a working electrode and mainly formed by mixing graphene, thionine, cholesterol oxidase, horse radish peroxidase and chitosan. The preparation method of the enzyme biosensor comprises the following steps: firstly uniformly mixing a thionine solution, a chitosan solution of the graphene, a horse radish peroxidase solution and a cholesterol oxidase solution, dripping onto the processed working electrode, forming the three-electrode system together with a reference electrode and a counter electrode to obtain the enzyme biosensor. The enzyme biosensor disclosed by the invention has the advantages of economical efficiency, simplicity, rapidness, sensitivity and the like, is simple in preparation and can be used for the quantitative determination of the cholesterol.

The invention relates to method for preparing a functionalized composite nano-fiber modified electrode. The method specifically comprises the steps of (1) preparing a spinning solution; (2) preparing composite nano-fibers through electrostatic spinning so as to form a composite nano-fiber PA6-MWNTs modified electrode; (3) carrying out electrical-polymerization thionine functionalization on the composite nano fibers: soaking the composite nano-fiber PA6-MWNTs modified electrode into a polymerization solution containing thionine monomers PTH, applying a voltage to the modified electrode so as to carry out anodizing treatment, then, carrying out cyclic volt-ampere scanning, washing away the thionine monomers, adsorbed to the modified electrode, by using a phosphate buffer solution PBS, forming a functionalized composite nano-fiber electrode modification material PA6-MWNTs / PTH layer on the surface of the electrode after the polymerization reaction is ended, thus obtaining the functionalized composite nano-fiber PA6-MWNTs / PTH modified electrode. According to the method, a functionalized composite nano-fiber electrode modification material which has the characteristics of good stability, large specific surface area, good biocompatibility, high electron transfer rate, uniformly-distributed diameter and pore size, and the like is obtained.

Disclosed is a novel compound suitable as an electron-transporting material for organic electronic devices. Also disclosed is an organic electronic device using such a compound which has higher sensitivity and longer life than conventional organic electronic devices. Specifically disclosed is a compound having a structure wherein constitutional units represented by the general formula (1) below are bonded to one another without the intermediary of a linking group. (1) [In the formula, X1-X4 independently represent an oxygen atom, sulfur atom or NR0 (wherein R0 represents a hydrogen atom or a substituted or unsubstituted monovalent organic group); Z0 represents a tetravalent organic group; and * represents a bonding position.

The invention relates to a preparation method of an optical composite nano-fiber material. The method comprises the steps of 1) preparing a nano gold-multi-wall carbon nano tube compound Au-MCNT; 2) preparing a spinning solution; 3) preparing the optical composite nano-fiber material in an electrostatic spinning way. In the electrostatic spinning, the prepared uniform and transparent precursor electrostatic spinning solution is arranged in an injector, a positive electrode of a high-voltage electrostatic generator is connected with a needle, a negative electrode is connected onto a clean bare electrode, the liquid is supplied by adopting a trace injection pump and directly applied to the injector needle through the high-voltage electrostatic power generated by the high-voltage electrostatic generator, and the optical composite nano-fiber is collected onto the bare electrode. The nano gold-multi-wall carbon nano tube compound with good conductivity and large specific surface area and capable of stably and firmly loading a great amount of trisruthenium Ru(bpy)3<2+> is doped with the spinnable macromolecular nylon 6 with good stability to obtain the precursor electrostatic spinning solution, and the optical composite nano fiber is obtained through the one-step electrostatic spinning method.

The invention discloses a modified silica nanoporous membrane modified electrode, a preparation method and an application thereof, and belongs to the technical field of novel materials. The preparation method comprises the following steps of: (1) preparing a silica nanoporous membrane having an open pore structure on an electrode substrate; and (2) inserting graphene quantum dots into pores to modify the silica nanopores to prepare the modified silica nanoporous membrane modified electrode by using a electrophoresis method, an electrostatic adsorption method, or a covalent immobilization method. The modified electrode, the preparation method and the application thereof insert small-sized GQDs as a functional block into pores to modify a VMSF electrode to prepare a variety of sensing interfaces. The electrode can realize a pre-enrichment effect on an object to be detected due to the electronegativity of the pores, and the coordination effect on metal ions and the pi-pi stacking action on the dopamine of the graphene quantum dots, so that the detection property of the object to be detected is remarkably improved. The great application prospects are achieved in direct and high-sensitivity electrochemical detection of multiple types of active compositions in complex samples combined with the anti-staining / anti-interference ability of the VMSF.

The invention discloses a preparation method for a nanogold-nanofiber functional composite modified electrode. The preparation method specifically comprises the following steps of (1) preparing a spinning solution; (2) performing electrostatic spinning to prepare composite nanofibers to form a composite nanofiber PA6-MCWNTs modified electrode; and (3) performing functionalization on composite nanofibers through electro-deposition nanogold, namely immersing the composite nanofiber PA6-MCWNTs modified electrode into deposition liquid containing HAuCl4, reducing HAuCl4 into nanogold by adopting a multi-potential step change method, and synchronously and directly depositing the nanogold on the surfaces of PA6-MCWNTs composite nanofibers, thus obtaining the nanogold / nanofiber functional composite AuNPs-PA6-MCWNTs modified electrode. The preparation method can be used for obtaining a functional composite electrode modified material with the characteristics of high stability, large specific surface area, high biological compatibility, high electron transmission rate, uniform nano diameter aperture distribution and the like.

The invention belongs to the technical field of electrochemical biosensors, and discloses a hydrogen peroxide biosensor based on sulfonated carbon nanotube composited with horseradish peroxidase, preparation and application thereof. The biosensor is composed of a reference electrode, a counter electrode and a modified working electrode, the modified working electrode is composed of a working electrode and a substance recognition film solidified on the surface of the working electrode, wherein the substance recognition film is mainly composed of a sulfonated carbon nanotube dispersion, a horseradish peroxidase solution and a perfluorosulfonic acid resin solution, and formed on the surface of the working electrode. The invention also discloses a method for preparing a sensor. The preparationmethod of the invention is simple and low in cost; the obtained sensor has good selectivity, sensitivity and stability, the enzyme has a fixed quantity and stability, and has good electrocatalytic performance; the hydrogen peroxide biosensor has strong anti-jamming capability, a wide detection range and a low detection limit, and can detect the hydrogen peroxide accurately.

The invention relates to a preparation method of a three-dimensional graphene lactic acid sensor. The preparation method comprises the following steps: promoting growth of a three-dimensional graphene nano wall by virtue of a plasma-enhanced chemical vapor deposition method by taking a copper foil as a substrate; drifting a three-dimensional graphene block on the surface of an Fe(NO3)3 solution so as to etch the copper foil, cleaning the copper foil by virtue of ultra-pure water and transferring the copper foil to a polyethylene terephthalate (PET) base material; printing three electrodes on the surface of the three-dimensional graphene / PET by virtue of a screen printing technology, and immobilizing lactase oxidase on the surface of the three-dimensional graphene by virtue of a chitosan-glutaraldehyde cross-linking method, so as to conduct functionalizing treatment on the electrodes; and finally, conduct sensitivity, stability, real-time performance and specificity lactic acid detection on the electrodes with the assistance of an electrochemical workstation, so that the required three-dimensional graphene lactic acid sensor is obtained. According to the preparation method disclosed by the invention, the three-dimensional graphene lactic acid sensor is prepared in a mode of being economic and environment-friendly, simple and efficient and controllable in quality, and due to the graphene nano wall which has the advantages of being rich in three-dimensional conductive network structure, huge in specific surface area and the like, the sensitivity and the real-time performance of lactic acid detection can be effectively improved; and the sensor is applicable to the fields of medical care and health.

The invention belongs to the field of content detection of heavy metals and particularly relates to a method for detecting the concentration of lead ions in a solution. The method comprises the following steps: by taking an aminated graphene and beta-cyclodextrin modified glassy carbon electrode as a working electrode, reducing metal ions in the solution by adopting the working electrode and utilizing a square wave stripping voltammetry method, and then performing oxidation detection to obtain a square wave stripping voltammetry curve of the metal ions; reading a current value according to the square wave stripping voltammetry curve of the metal ions, obtaining the concentration of the lead ions in the solution by utilizing a lead ion concentration standard curve. By utilizing the aminated graphene and beta-cyclodextrin modified glassy carbon electrode for detecting the lead ions, the method disclosed by the invention is simple and convenient in detection process, high in sensitivity, low in detection limit and capable of realizing rapid sensitive detection of the lead ions in an actual sample.

The invention relates to an anthracene deviant containing triazine ring, its preparing method and application, which is prepared through trilooping reaction under strong protonic acid catalysis with cyano anthracene derivant. The molecular structure of this material employs triazine ring as parent body and employs anthracene derivant as extending arm. The product can be used as luminescent layer for organic light-emitting diode, and the produced device emits blue light. The invention is characterized by the simple synthetic process, easy for purification, high heat stability, easy to dissolve into normal organic dissolvent and high fluorescent light intensity.

The invention belongs to the field of preparation of anticorrosive paint, and in particular relates to anticorrosive paint added with a graphene / zinc composite material and a preparation method of the anticorrosive paint. The anticorrosive paint is prepared from the following components (in weight percentage composition): 20 to 90 percent of polyurethane, 5 to 15 percent of graphene / zinc composite material, 1 to 10 percent of tinting pigment, 5 to 10 percent of filler, 0.1 to 3 percent of dispersing agent, 0.1 to 3 percent of wetting agent, 0.1 to 3 percent of thickener, 0.1 to 1 percent of flatting agent, 0.1 to 1 percent of defoamer, 0.1 to 1 percent of bactericide and 1 to 35 percent of water. The anticorrosive paint prepared by the preparation method is excellent in anticorrosive effect, harmless to the environment, simple in process, and is prone to industrial production.

The invention provides a CO2 low-temperature methanation catalyst, which belongs to the technical field of the methanation catalyst. The catalyst comprises a carrier, an active component and an auxiliary agent, the carrier comprises Al2O3 and carbon nanotubes, the active component is NiO, and the auxiliary agent is selected from one or two of La2O3 and CeO2; by taking total mass percentage of thecatalyst, the content of the Al2O3 is 55 to 85 wt%, the content of the CNTs is 1 to 20 wt%, the content of the active component NiO is 10 to 25 wt%, and the content of the auxiliary agent is 0 to 5 wt%. The invention also provides a preparation method and application of the catalyst. The catalyst of the invention uses Al2O3-CNTs as a composite carrier to load metal nickel, which can significantlyimprove the low temperature stability of the catalyst. The catalyst of the invention has high strength and excellent CO2 low-temperature methanation activity, and the catalyst of the invention after high temperature operation has high low-temperature activity and good catalyst stability. The catalyst preparation method is simple, and has industrial application prospect.

The invention discloses a modified graphite felt electrode as well as a modification method and application thereof, and belongs to the technical field of electrochemical water treatment. Through useof a graphite felt as a matrix material and a sulfuric acid solution as an electrolyte, the ratio of oxygen-containing functional groups on the surface of the graphite felt is improved, and the electrochemical performance of the graphite felt electrode is improved by taking the oxygen-containing functional groups as active sites. Compared with a polarization-free graphite felt electrode prepared under the same condition, the polarization graphite felt electrode has higher oxidation efficiency.

The invention belongs to the technical field of a biosensor, and discloses an enzyme biosensor for detecting inosine monophosphate(IMP) and a preparation method and an application thereof. The lineardetection range of the enzyme biosensor is 0.313-210 microgram / L, and the detection limit is 0.238 microgram / L. The enzyme biosensor is formed by a reference electrode, a counter electrode and a modified electrode obtained by curing an IMP-sensitive substance recognition film on the surface of a working electrode. The substance recognition film is formed by a composite solution a, a double-enzymecomposite solution b formed by a 5'-nucleotidase solution and an xanthine oxidase solution by the volume ratio 1: 1, and a bovine serum albumin solution by the volume ratio of 1: 1: 1, wherein the composite solution a is composed of a MXene-Ti3C2Tx solution (T is selected from OH, O or F), a chitosan solution, a chloroauric acid solution and a chloroplatinic acid solution by the volume ratio of 12:1.2:1:1. The enzyme biosensor is simple, fast and accurate and high in sensitivity, and can be used for quantitative detection of inosine monophosphate(IMP) in food.

The invention discloses a method for electromagnetically detecting the activation level of an STAT 3 protein through a DNA probe ligand and application. By use of STAT3 which is an important transcription factor and dynamic reversible and controllable mutual action between two natural ligands which are DNA and polypeptide, a DNA probe capable of specifically identifying a protein is designed; the polypeptide is used for controlling reversible combination and dissociation between the target protein STAT3 and the DNA probe; by stable coordination interaction between Zr<4+> and a phosphate group and a phosphorylated nano-graphene composite beacon, catalytic signal amplification is realized. According to the method, by introduction of the phosphorylated nano-graphene composite beacon serving as a signal amplification strategy, the phosphorylated nano-graphene composite beacon is stable and difficult to inactivate, thus finally realizing sensitive, efficient and stable detection for the activated STAT3 protein.

The invention provides a Pt / Fe3O4-CeO2 composite material and a preparation method thereof. Pt nano-particles are deposited on the surfaces of CeO2 nanoparticles coated with Fe3O4. The preparation method comprises the following steps of 1, dispersing nano-CeO2 in water to obtain a nano-CeO2 solution having a concentration of 0.10 to 0.15mol / L, 2, carrying out ultrasonic oscillation, 3, orderly adding concentrated hydrochloric acid, a soluble Fe<3+> salt and a soluble Fe<2+> salt into the nano-CeO2 solution to obtain a mixed system, wherein the weight of the concentrated hydrochloric acid is 2% of the weight of the nano-CeO2 solution; a mole ratio of the soluble Fe<3+> salt to the soluble Fe<2+> salt is 2: 1; and the concentration of the soluble Fe<3+> salt in the mixed system is in a range of 0.8 to 1.0mol / L, 4, adding an ammonia water solution into the mixed system, 5, sequentially stirring for 20 to 40min to obtain a Fe3O4-CeO2 nanocomposite material, 6, preparing the Fe3O4-CeO2 nanocomposite material into a dispersion liquid having a mass concentration of 2.0 to 2.5mg / mL, 7, mixing the dispersion liquid and a H2PtCl4 aqueous solution, and 8, adding an NaBH4 aqueous solution into the mixed solution obtained by the step 7 to obtain the Pt / Fe3O4-CeO2 composite material. The invention also provides a use of the Pt / Fe3O4-CeO2 composite material in electroactive material detection.

The invention discloses an electrochemical sensor for detecting lead ions and / or cadmium ions, and a preparation method and an application thereof. The electrochemical sensor includes a glassy carbonelectrode, of which the surface of a reaction terminal is modified by ordered mesoporous carbon supporting hollow spherical bismuth oxide, which is formed with the ordered mesoporous carbon as a carrier, of which the surface supports the hollow spherical bismuth oxide. The preparation method includes a step of modifying the ordered mesoporous carbon supporting hollow spherical bismuth oxide onto the surface of the reaction terminal of the glassy carbon electrode. The electrochemical sensor has advantages of good stability, long service life, wide detection range, low detection limit, good selectivity and strong anti-interference capability. The preparation method has simple processes, low cost and convenient operations, is pollution-free and has extensive application range. The electrochemical sensor is used for detecting lead ions and / or cadmium ions, has simple operation, low cost, short responsive time and high sensitivity, and has great application prospect.

The invention relates to a biomass energy utilization technology, and aims to provide a method for promoting preparation of biomethane by cobalt-nickel zeolite imidazate framework derived porous carbon. The method comprises the following steps: mixing cobalt chloride, polyvinylpyrrolidone and a methanol solution of dimethylimidazole, violently stirring, and aging to obtain a cobalt zeolite imidazate framework; washing, drying in vacuum, and grinding to obtain cobalt zeolite imidazate framework powder; dispersing in ethanol, adding nickel dichloride hexahydrate, and stirring to form a cobalt-nickel zeolite imidazate framework with an eggshell structure; drying in vacuum, and carbonizing in a tube furnace under a nitrogen condition to obtain porous carbon microspheres containing cobalt-nickel nanoparticles; and washing with hydrofluoric acid, drying in vacuum, and grinding into powder to obtain the cobalt-nickel zeolite imidazate framework derived porous carbon. According to the method,the biomethane production performance of a fermentation system can be effectively improved, the electron transfer performance of the system is optimized, the content of electroactive extracellular polymeric substances in the system is increased, and electron shuttle mediated interspecific electron transfer is enhanced.

The invention discloses a preparation method of electrochemical sensor for sulfonamide molecule, and belongs to the technical field of new nano functional materials and biosensor. The method firstly prepares a nickel hydroxide nanosheet array on a disposable throwable electrode, and uses the large specific surface area and a high activity hydroxyl functional group and an amino functional group ofpolydopamine to sequentially prepare a polydopamine film containing an electron mediator and a molecularly imprinted polymer taking a sulfonamide molecule as a template molecule directly on the nickelhydroxide nanosheet array by adopting an in-situ growth method, after eluting the template molecule, the position of the original template molecule becomes a hole, that is, the molecularly imprintedpolymer eluting the template molecule, thus, an electrochemical sensor for the sulfonamide molecule is prepared.

The invention relates to a preparation method and application of an electrochemical immunosensor based on palladium-doped molybdenum disulfide nanospheres, which belongs to the technical field of nanomaterials and electrochemical analysis. By adopting the electrochemical immunosensor prepared by molybdenum disulfide nanospheres modified by palladium nano particles doped cetyltrimethylammonium bromide, the high-sensitivity detection of N-terminal B-type N-terminal pro-brain natriuretic peptide is realized.

A new electrochemical method for determining dissolved oxygen concentration is developed. It employs cobalt based oxide or complex to modify a conductive electrode surface. This method can be applied to determine dissolved oxygen in regard to medical and environmental demands. The chemical formula of the cobalt based oxide or complexes can be shown as CoxOy or CoaLb. Both “x” and “a” represent the number of cobalt atom; while “y” and “b” represent the number of oxygen atom and the number of coordinating ligand, respectively. For instance, the best known example of cobalt oxide is Co3O4, and the best known examples of cobalt complexes are cobalt phthalocyanine (CoPC) and cyanocobalamin (vitamin B12), or other macrocyclic complexes with a metallic nucleus of cobalt. The present invention determines the concentration of dissolved oxygen in solution in potentiostatic mode with three electrodes. As a result, the dissolved oxygen can be determined between 0.0V and −0.3V vs. Ag / AgCl, thereby significantly reducing the interferences from the easily oxidized compounds in water solutions.

The invention belongs to the technical field of biological sensors, and discloses a non-enzyme sensor based on nitrogen-doped graphene and a preparation method and application thereof. The sensor consists of a reference electrode, a counter electrode and a modified working electrode, wherein the modified working electrode consists of a working electrode and a material recognizing membrane cured on the surface of the working electrode, and the material recognizing membrane consists of a nitrogen-doped graphene composite material and perfluorinated sulfonic acid resin. The non-enzyme sensor provided by the invention is applied to the detection of hydrogen peroxide, is wide in detection range, is low in detection limit, and has stable performance and a good application prospect; a reaction is implemented in a neutral environment at the room temperature.

The invention discloses a preparation method and application of a nitrogen-containing super-crosslinked polymer derived Co@CN catalyst. The preparation method comprises the following steps: dissolving a benzo nitrogen-containing heterocyclic compound, benzene, dimethoxymethane and anhydrous ferric trichloride in an organic solvent, heating to fully react, and purifying and drying the product to obtain the nitrogen-containing super-crosslinked polymer; then, dispersing the polymer and cobalt salt into deionized water, adding urea, transferring into a reaction kettle, carrying out heat treatment under an overturning condition, cooling, separating, washing, drying and purifying to obtain a precursor; and finally, pyrolyzing the precursor in a nitrogen atmosphere to prepare the nitrogen-containing super-crosslinked polymer derived Co@CN catalyst with high catalytic activity, and applying the Co@CN catalyst to a reaction for catalyzing selective hydrogenation of quinoline compounds to prepare tetrahydroquinoline compounds. According to the method, the yield of the tetrahydroquinoline compound prepared from the quinoline compound is increased, and the reaction temperature is reduced.