125 results about "Copper nanowires" patented technology

The invention belongs to the technical field of photoelectric catalytic materials, and particularly relates to an experimental method for rapidly preparing a copper oxide nanowire and application of the copper oxide nanowire. The preparation method comprises the following steps: adopting a copper net as a substrate, rapidly preparing a Cu (OH) 2 nanowire array on the surface of the copper net through a constant-voltage anodic oxidation method, rapidly dehydrating Cu (OH) 2 through high-temperature heat treatment, and preparing the CuxO nanowire array in situ. Compared with the existing P-type semiconductor material, the material has a wider visible light absorption range as a photoelectric catalytic material, and has better performance in the fields of hydrogen production through photoelectric water decomposition and photo-assisted Li-CO2 batteries. The problem of low light energy utilization rate is solved, and the copper oxide nanowire material is beneficial to separation of photo-induced electrons and hole pairs, so that the charge-discharge voltage close to a theoretical value can be measured when the copper oxide nanowire material is used as the positive electrode material of the Li-CO2 battery.

The invention relates to a preparation method of a multi-site silver (Ag) and nickel hydroxide (Ni (OH) 2) modified copper (Cu) nanowire catalyst (Ag-Ni (OH) 2) / Cu NW) and application of the multi-site silver (Ag) and nickel hydroxide (Ni (OH) 2) modified copper (Cu) nanowire catalyst. A cation exchange and electrodeposition method is adopted to prepare an electrocatalytic nitrate reduction reaction NO3-RR series catalyst with three sites of Ag, Ni (OH) 2 and Cu. Based on the synergistic effect of three sites, Ag in the catalyst promotes conversion from nitrate NO3 <-> to nitrite NO2 <->, Ni (OH) 2 promotes dissociation of water H2O to generate free hydrogen * H, Cu atoms near Ni (OH) 2 accelerate conversion from NO2 <-> to ammonia NH3, and the efficient series catalytic process is achieved. Under the condition of-0.1 V vs. Reversible hydrogen electrode RHE in a 1M potassium hydroxide solution containing 50 mM of potassium nitrate, the NH3 yield of 4.01 mgh <-1 > cm <-2 > and the NH3 Faraday efficiency of 97.3% are obtained, under the condition of 0V vs. RHE, the excellent energy efficiency of 46.5% is achieved, the excellent catalytic activity is kept in a NO3 <-> solution with the wide concentration, and the good sewage treatment capacity is achieved. The invention provides a new design thought for tandem catalysis, and has a wide application prospect in the field of NO3-RR.

The invention belongs to the field of electronic packaging, and relates to a nano-copper metal material for low-temperature sintering conductive paste and preparation and application of the paste of the nano-copper metal material. The nano-copper metal material comprises copper nanoparticles and copper nanowires, and the copper nanoparticles and the copper nanowires are both prepared through a one-step hydrothermal method: (1) the copper nanoparticles are prepared, specifically, the high-purity copper nanoparticles are obtained through a hydrothermal reaction by adjusting the pH value; (2) preparing a copper nanowire: carrying out hydrothermal reaction on a copper source, a reducing agent and an end-capping reagent, so that copper ions are reduced into quintuple twin crystal seeds in one step and further directionally deposited into the copper nanowire; and (3) preparing conductive paste: mixing the nano-copper material and an organic reagent according to a certain proportion, and homogenizing to obtain the low-temperature sintering type conductive copper paste. The low-temperature copper paste is used for preparing the low-temperature copper paste for bonding a chip and a substrate. The prepared nano-copper metal material for the low-temperature sintering conductive paste is stable in size and simple in preparation process, and the prepared paste is good and excellent in sintering performance (the shear strength is 25 MPa, and the thermal conductivity is 4 W / m.K).

The invention relates to a cable shielding material with stable high-temperature resistance as well as a preparation method and application of the cable shielding material. The cable shielding material with stable high-temperature resistance comprises the following raw materials in percentage by mass: 45.0-75.0% of matrix resin, 10.0-35.0% of carbon black, 0.5-5.0% of copper nanowires, 0.1-1.0% of an antioxidant and 0.5-2.0% of a cross-linking agent. The copper nanowire and the carbon black are used together, so that the conductivity of the shielding material is remarkably improved, and particularly in a high-temperature environment, the copper nanowire can be in lap joint with the carbon black after the resin matrix is expanded, so that the shielding material can still keep the conductivity at a high temperature. The copper nanowires are oriented along the extrusion direction in the extrusion cabling process of the shielding material, so that the electric field distribution can be strengthened and homogenized, and the durability of the cable is improved. Meanwhile, due to the introduction of the copper nanowires, the use amount of carbon black is effectively reduced, the smoothness of the material is improved, and the defect rate in the cable manufacturing process is reduced.

The invention relates to the technical field of sensors, in particular to a strain sensor based on a multi-layer wrinkled structure and a preparation method and application thereof.The sensor simulates a skin wrinkled structure and belongs to a capacitive sensor, the sensor comprises a flexible medium insulating tape and two layers of flexible layered film electrodes, the flexible layered film electrodes are respectively positioned on two sides of the flexible dielectric insulating tape and cover the flexible dielectric insulating tape, and the flexible layered film electrodes are formed by combining a platinum-modified copper nanowire film (Cu (at) Pt film) with a flexible substrate material polyvinylidene fluoride (PVDF) as a conductive layer. The sensor has high sensitivity and a wide stretching range, overcomes the defects in existing material selection, and has potential application in the fields of exercise monitoring, health monitoring and information transmission.

The invention relates to a copper-based composite catalyst and a preparation method and application thereof.The copper-based composite catalyst comprises an inner core and a shell wrapping the surface of the inner core, the inner core comprises copper nanowires, and the shell comprises hydroxyl aluminum oxide. According to the copper-based composite catalyst provided by the invention, the surface of the copper nanowire inner core is coated with the aluminum hydroxide shell, and the aluminum hydroxide in the shell and the copper nanowire in the inner core construct a copper-oxygen-aluminum metal interface site on the surface of the inner core through the lewis acid-alkali interaction, so that the migration energy of the surface of copper atoms can be improved; the copper species in the inner core are stabilized, the reconstruction of the copper-based catalyst is avoided, and the selectivity and the stability of the copper-based composite catalyst are improved.

Embodiments of the present disclosure pertain to a material that includes: (1) a first copper-based layer; (2) a copper nanowire layer above the first copper-based layer, which generally includes a plurality of copper nanowires embedded with a polymer; and (3) a second copper-based layer positioned above the copper nanowire layer such that the copper nanowire layer is sandwiched between the first copper-based layer and the second copper-based layer. Additional embodiments of the present disclosure pertain to methods of forming a material of the present disclosure.

The invention discloses a method for preparing a copper oxide nanowire material by using a dynamic gas phase atmosphere, and belongs to the technical field of seawater desalination and photo-thermal materials. The technical problem that the service life of the copper oxide nanowire material cannot be ensured while the hydrophilicity of the copper oxide nanowire material is realized in the prior art is solved. According to the technical scheme, the preparation method comprises the following steps: immersing a pretreated copper net into a mixed solution of persulfate and hydroxide, and growing a copper hydroxide nanowire on the copper net through a chemical deposition method; and drying the copper hydroxide nanowire grown on the copper mesh, and then carrying out heat treatment to obtain the copper oxide nanowire loaded on the copper mesh. The preparation method has the beneficial effects that through heat treatment in a dynamic gas phase atmosphere, the hydrophilicity of the copper oxide nanowire is improved, and meanwhile, the copper oxide nanowire has a better long-term service life.

The invention discloses a layered nano-porous copper loaded cuprous oxide / copper oxide nanowire composite material as well as a preparation method and application thereof. The material is a thin strip and comprises an amorphous substrate thin strip, multiple layers of nano-porous copper covering an amorphous substrate and a cuprous oxide / copper oxide two-component heterojunction nanowire loaded on the surface of the nano-porous copper. The preparation method comprises the following steps: firstly, freely dealloying an amorphous ribbon, and adding PVP (Polyvinyl Pyrrolidone) into dealloying corrosive liquid to generate layered nano-porous copper; then, copper hydroxide nanowires grow on the surface of each layer of nano-porous copper in situ through the anodic oxidation technology; and finally, converting the copper hydroxide into cuprous oxide / copper oxide nanowires with different component proportions by regulating and controlling the temperature by adopting a heat treatment process. The prepared composite material has a larger specific surface area and more active sites, and has unique structure and performance advantages in the field of photocatalytic degradation of organic dyes.

The invention belongs to the technical field of composite films, and particularly relates to a super-soft, electricity-conducting and heat-conducting film electrode and a preparation method thereof. The preparation method comprises the following main preparation steps: firstly, preparing a single-layer boron nitride nanosheet BNNS from a two-dimensional heat conduction material hexagonal boron nitride BN through an ultrasonic stripping technology, and then carrying out hydroxylation treatment on the BNNS to form a hydroxylated boron nitride nanosheet HO-BNNS; the preparation method comprises the following steps: mixing a HO-BNNS aqueous solution with a silver nanowire (AgNWs) or copper nanowire (CuNWs) aqueous solution, mixing with a polyvinyl alcohol (PVA) polymer substrate material to form a uniform dispersion liquid, pouring the mixed solution on the surface of a prefabricated metal nanowire thin film electrode (a substrate can be a flat substrate such as a PET flexible polymer or a silicon wafer rigid substrate), and performing high-temperature curing to obtain the metal nanowire thin film electrode. And finally, the cured film is peeled off from the substrate, so that the super-soft film electrode with excellent electric conduction and heat conduction performance is prepared, and the film can be repeatedly folded and has super-flexibility.

The present invention relates to the technical field of nanowire electromagnetic shielding film preparation, and discloses a composite nanowire staggered interconnected electromagnetic shielding film and a preparation process. The S coordinating atoms in a cationic coordination monomer form Cu-S coordination bonds with nano-copper wires, which are adsorbed on the surface of the nano-copper wires to obtain positively charged copper nanowires. The S coordinating atoms in an anionic coordination monomer form Ag-S coordination bonds with nano-silver wires, which are adsorbed on the surface of the nano-silver wires to obtain negatively charged silver nanowires. The amount of positively charged substances on the copper nanowires is greater than the amount of negatively charged substances on the silver nanowires. The silver nanowires and nano-copper wires are electrostatically self-assembled by electrostatic adsorption force to obtain positively charged silver-copper composite nanowires with a staggered interconnected distribution. The silver nanowires are spontaneously deposited on a negatively charged flexible substrate under the action of electrostatic adsorption to obtain a composite nanowire staggered interconnected electromagnetic shielding film. The electromagnetic shielding film exhibits excellent photoelectric properties.

The present invention relates to the technical field of electrochemical energy materials, and specifically discloses a molybdenum nitride / nickel cobalt nitride nanosheet heterostructure electrocatalytic material, its preparation method and application. The method comprises S1, preparing copper hydroxide nanowires loaded on copper foam; S2, preparing copper nanowires loaded on copper foam; S3, preparing copper nanowire-loaded molybdenum-doped nickel cobalt nanosheets; S4, placing the copper nanowire-loaded molybdenum-doped nickel cobalt nanosheets in a tube furnace, and nitriding them in an ammonia nitrogen atmosphere to obtain a molybdenum nitride / nickel cobalt nitride nanosheet heterostructure electrocatalytic material. The internal resistance of the material is reduced by electron transfer and heterostructure between molybdenum nitride and nickel cobalt nitride, and compared with precious metal platinum wire, the material has excellent high current density hydrogen evolution performance. The preparation method provided by the present invention has the advantages of simple synthesis process, short synthesis cycle and low production cost. In addition, no hydrothermal reaction is required during preparation, the material has high safety and reliable repeatability, and is very suitable for large-scale industrial production.

The application discloses a copper-bismuth bimetallic catalyst and a preparation method and application thereof. The copper-bismuth bimetallic catalyst comprises a copper substrate and copper-bismuth nanowires grown on the copper substrate, the copper-bismuth nanowires comprise copper nanowires and a metal bismuth layer loaded on the copper nanowires, and the mass fraction of bismuth in the copper-bismuth nanowires is 40% to 60%. The preparation method of the catalyst comprises the following steps: after in-situ growth of copper hydroxide nanowires on the copper substrate, the copper-bismuth bimetallic catalyst is prepared through heat treatment, electrochemical reduction treatment and bismuth deposition. Meanwhile, the copper-bismuth bimetallic catalyst can not only make full use of the copper and bismuth bimetallic effect, effectively improve the activity, stability and selectivity of electrocatalytic reduction of carbon dioxide, but also has the advantages of simple and controllable preparation, wide application potential window and wide application environment.

This invention discloses a method for preparing a three-dimensional integrated lumbar support cushion. The raw materials of the lumbar support cushion include: ethylene-vinyl acetate copolymer, polyether-type thermoplastic polyurethane elastomer, physically foamed microspheres, azodicarbonamide, caprolactam-blocked 4,4'-diphenylmethane diisocyanate, surface-modified copper nanowires, and silver-loaded silicone composite components. The preparation process is as follows: the matrix resin and modified copper nanowires are melt-blended at high temperature, and then mixed with the foaming system, crosslinking agent, and composite components at low temperature to obtain a blended base material; the blended base material is injection molded, followed by static differential temperature field for pressure holding and curing, and finally cooled and demolded. This invention utilizes copper nanowires to construct a thermally conductive network, which, combined with the external temperature difference, forms a continuous foaming ratio and crosslinking density gradient inside, eliminating the physical phase interface of traditional multi-material splicing, significantly improving the tear resistance and fatigue life of the transition zone; and utilizes cooling phase separation to form an anti-slip and antibacterial skin layer.

The invention provides a plasmon copper-based nano material, a preparation method thereof and application of the plasmon copper-based nano material in a carbon dioxide capture-conversion system.The preparation method comprises the steps that a copper nanowire modified by polytetrafluoroethylene is adopted as a plasmon catalyst, carbon dioxide is efficiently adsorbed and captured through organic amine, and under excitation of polarized light with the specific wavelength, the carbon dioxide is converted into the plasmon copper-based nano material. And efficient carbon dioxide electroreduction is realized. Compared with the prior art, carbon dioxide capture and photoelectrocatalysis carbon dioxide conversion of the plasmon copper-based nano material are combined, rapid capture and release of carbon dioxide are achieved, and the Faraday efficiency of reducing carbon dioxide into methane reaches up to 90% or above. The invention constructs a carbon dioxide capture-conversion system with industrial application potential, and provides a new path for realizing energy conservation and emission reduction.

The present invention provides a titanium alloy anode plate and a preparation method thereof, belonging to the technical field of anode plates. Ti powder and Mn powder are mixed, ball-milled, and subjected to plasma spheroidization treatment to obtain spherical TiMn alloy powder, which is flame-sprayed on the surface of a titanium plate, followed by gradient manganese infiltration. After surface treatment, copper nanowire-deposited graphene@spherical TiMn alloy powder is evenly sprayed, dried, and a titanium alloy anode plate is prepared. The titanium alloy anode plate prepared by the present invention can be used in the production of electrolytic manganese dioxide, has anti-passivation performance, and under a current density of 100 A / m<supgt;2< / supgt> and normal industrial electrolysis conditions, the cell voltage can be stably within 2.3 - 2.4 volts. The product adheres well to the anode, without cracking or detachment phenomena, overcoming the defects of existing industrial anodes, and is an ideal anode for electrolytic manganese dioxide.

The application discloses a copper oxide nanowire loaded silver monatomic catalyst, a preparation method and application thereof, and comprises a substrate, CuO nanowires and metal Ag monatomic atoms loaded on a CuO nanowire electrode layer; the substrate is a commercial copper foam, and the substrate is used for providing a copper source and preparing an array material of the metal Ag monatomic atoms on the CuO nanowires. The application adopts the above-mentioned copper oxide nanowire loaded silver monatomic catalyst, the preparation method and the application thereof, through silver monatomic atom modification, copper-silver metal interaction jointly regulates an intermediate product in an adsorption electrocatalytic reduction process, excellent electrocatalytic nitrophenol reduction performance is obtained, and the application is suitable for environmental pollution treatment and pharmaceutical synthesis development fields.

This invention provides a method for producing copper nanowires that exhibits excellent selectivity and can be implemented with a simple configuration. [Solution] A method for producing copper nanowires, comprising the following step 1. Step 1: A mixture containing copper oxide (a), halogen ions (b), a nonionic polymer compound (c), alkyl quaternary ammonium ions (d), a reducing agent (e), and water (f) is heated to 50°C or higher to precipitate copper nanowires.

This invention relates to the field of nanomaterial preparation, specifically disclosing a method for preparing copper nanowires, comprising the following steps: (a) dissolving copper chloride dihydrate in deionized water; (b) adding glucose, sodium borohydride, and hexadecylamine, mixing for a period of time until a sky-blue suspension is obtained; (c) reacting at a certain temperature for a period of time; cooling to room temperature, and washing to obtain the copper nanowires. This invention also discloses the copper nanowires.

The present invention provides a tubular Graphyne coated bismuth particle nanomaterial and its preparation method and application. The preparation method of the material comprises the following steps: using a copper catalyst to catalyze a precursor to perform an acetylene-acetylene coupling reaction to prepare a Graphyne coated copper nanomaterial; using an electrochemical replacement reaction to replace the metal copper in the Graphyne coated copper nanowire with metal bismuth to obtain the material. The material can effectively solve the problem that the existing bismuth material has a large volume change during the charge and discharge process, resulting in rapid performance degradation.

The invention discloses a preparation method of a high-conductivity multivalent nanowire and application of the high-conductivity multivalent nanowire to a non-enzyme glucose sensor. The copper nanowire with a high length-diameter ratio is prepared, a certain amount of thiourea is directly added into an ethanol solution of the copper nanowire, and conversion from the copper nanowire to the high-conductivity multivalent nanowire can be achieved under the condition of a specific reaction temperature. In the conversion process, the surface of the nanowire is synchronously induced to form a coarse structure, non-single valence copper sulfide active sites are constructed, and the formed synergistic effect can remarkably increase the number of the active sites, reduce an electrocatalytic oxidation reaction energy barrier and strengthen the specific adsorption capacity of glucose molecules, so that the non-enzyme glucose sensor is manufactured. The sensor shows ultrahigh detection sensitivity, ultralow response speed and excellent anti-interference performance, the preparation process is extremely simple, the cost is low, and the sensor has remarkable technical advantages and wide application prospects in the field of quantitative detection of glucose.

The invention provides a copper sulfide nanowire material and a preparation method and application thereof, copper atoms and sulfur atoms on the surface of the copper sulfide nanowire material exist in the form of compounds, and the main component is a Cu2S phase; the preparation method of the copper sulfide nanowire material comprises the steps that nickel chloride hexahydrate, copper acetylacetonate and dimethyl dioctadecyl ammonium chloride serve as raw materials to prepare a Cu nanowire in the presence of oleylamine, and then the Cu nanowire is subjected to vulcanization treatment to obtain the copper sulfide nanowire material. The preparation method is simple and flexible in reaction, the number of nanoparticles on the surface of the copper sulfide nanowire material can be controlled according to needs, and the prepared copper sulfide nanowire material contains copper sulfide nanowires with the diameter of 20-60 nm. The copper sulfide nanowire material can be applied to CO2 electrochemical catalytic reduction or water electrolysis hydrogen production, and the universality is good.

The invention provides a silver-coated copper nanowire, a preparation method thereof and a conductive material, and the preparation method comprises the following steps: mixing a copper salt solution, a first reducing agent and a surfactant, carrying out a heating reaction to obtain a copper nanowire solution, and carrying out first centrifugal sedimentation treatment on the copper nanowire solution to obtain a copper nanowire; the copper nanowires are dispersed in a PVP aqueous solution, CTAB is added, stirring is performed to obtain a PVP-CTAB dispersed copper nanowire solution, and the PVP-CTAB dispersed copper nanowire solution is mixed with a second reducing agent to obtain a copper nanowire plating solution; and mixing the silver precursor solution with the copper nanowire plating solution for reaction, and carrying out second centrifugal sedimentation treatment to obtain the silver-coated copper nanowire.

The application discloses a kind of three-dimensional ordered hollow cuprous oxide nano array and its preparation method and application, it is related to photoelectric detection technical field.Preparation method includes: impurity aluminum is oxidized, and the aluminum oxide template with the hole formed on surface is obtained, and after reaming, the three-dimensional porous aluminum oxide template with back aluminum is obtained;With three-dimensional porous aluminum oxide template as cathode, graphite is anode, in Cu electrodeposition liquid, constant current electrodeposition is carried out, and the three-dimensional porous aluminum oxide template with back aluminum loaded with copper nanowire is obtained;Three-dimensional porous aluminum oxide template with back aluminum is removed using alkali solution, and three-dimensional interconnected self-supporting copper nanowire array is obtained;Three-dimensional interconnected self-supporting copper nanowire array is annealed under local hypoxia environment, and three-dimensional highly ordered hollow cuprous oxide nano array is obtained by cooling down.The self-powered photoelectrochemical type photoelectric detector prepared by using the hollow cuprous oxide nano array has high light absorption rate, high specific surface area and high ion transmission rate, and is suitable for ultraviolet light detection.

The invention relates to the technical field of electrochemical energy materials, and particularly discloses a molybdenum nitride / nickel-cobalt nitride nanosheet heterostructure electro-catalytic material as well as a preparation method and application thereof. The method comprises the following steps: S1, preparing a copper hydroxide nanowire loaded on foamy copper; s2, preparing a copper nanowire loaded on the foamy copper; s3, preparing a copper nanowire loaded molybdenum doped nickel cobalt nanosheet; and S4, placing the copper nanowire loaded molybdenum doped nickel cobalt nanosheet in a tubular furnace, and nitriding in an ammonia nitrogen atmosphere to obtain the molybdenum nitride / nickel cobalt nitride nanosheet heterostructure electro-catalytic material. The internal resistance of the material is reduced through electron transfer and a heterostructure of molybdenum nitride and nickel-cobalt nitride, and compared with a precious metal platinum wire, the high-current-density hydrogen evolution performance is excellent. The preparation method provided by the invention has the advantages of simple synthesis process, short synthesis period and low production cost, does not need hydrothermal reaction during preparation, is high in safety and reliable in repeatability, and is very suitable for large-scale industrial production.

A conductive paste composition according to the present disclosure contains silver-coated copper nanowires with a core-shell structure; a binder mixture containing a silicone resin binder and a hydrocarbon-based resin binder; and an organic solvent, such that the conductive paste composition has a low sheet resistance and may withstand a high temperature, thereby implementing excellent conductivity and electromagnetic wave shielding properties. Furthermore, the conductive paste may be widely used in various fields such as electromagnetic wave shielding, solar cell electrodes, electronic circuits, and antennas.

The invention relates to the technical field of multifunctional fabrics, in particular to a waterproof and antistatic fabric and a preparation method thereof.The fabric sequentially comprises a super-hydrophobic protective layer, an efficient conductive buffer layer and a moisture absorption and sweat releasing comfortable layer from outside to inside, the super-hydrophobic protective layer comprises an organic silicon coating, the organic silicon coating contains a micropore structure, and the efficient conductive buffer layer is arranged between the micropore structure and the moisture absorption and sweat releasing comfortable layer. Boron nitride nanosheets and zinc oxide quantum dots are doped in the organic silicon coating; the efficient conductive buffer layer comprises a latticed layer formed by interweaving polylactic acid fibers and copper nanowire composite fibers, and a two-dimensional transition metal carbide derivative and a temperature-sensitive phase change material are loaded on the efficient conductive buffer layer; the moisture-absorbing and sweat-releasing comfortable layer comprises a modal blended material doped with natural rubber microcapsules and chitosan microspheres, and a moisture-sensitive material accounting for 1-3 wt% of the mass of the moisture-absorbing and sweat-releasing comfortable layer is added to the moisture-absorbing and sweat-releasing comfortable layer.

The invention relates to the technical field of flexible transparent electrode preparation and application, in particular to a copper nanowire ionic liquid flexible transparent electrode and a preparation method and application thereof. The preparation method comprises the following steps: assembling copper nanowires into a uniform and continuous thin film on a gas / liquid interface, carrying out transfer and conductivity improvement treatment, immersing the copper nanowire thin film into an ionic liquid solution, and drying to obtain the copper nanowire ionic liquid flexible transparent electrode with oxidation resistance. The flexible transparent electrode prepared by the invention has high mechanical and chemical stability, overcomes the key problem that a copper nanowire flexible transparent electrode is easy to oxidize and loses conductivity, is low in preparation cost, high in transparency and good in flexibility, and can be applied to the related fields of wearable electronic equipment, flexible touch screens, solar cells, intelligent windows and the like.

A method for controllable stepwise reduction of electrocatalytic unsaturated nitro compounds with potential regulation belongs to the field of organic electrocatalysis. In a three-electrode system, an electro-reduced copper nanowire catalyst (ER-Cu / CF) grown on copper foam is used as the cathode, a platinum sheet is used as the counter electrode, and an Ag / AgCl electrode is used as the reference electrode. The two poles of the electrolytic cell are separated by a nafion membrane to form an electrocatalytic reactor. In a neutral electrolyte containing nitro compounds, by adjusting the low direct current voltage, the electrocatalytic unsaturated nitro compounds are controllably stepwise reduced to obtain hydroxylamine intermediates, amino products, and fully reduced products with high selectivity and high yield. In the present invention, the selectivity and yield of the products are very high, it can be carried out at normal temperature and pressure, the operation is simple, green and safe, and the reaction controllability is high; it avoids problems such as low yield, poor selectivity, use of noble metal catalysts and toxic reagents, environmental pollution, and the need for high reaction temperature and pressure in other methods.

The invention belongs to the technical field of electronic paste, and discloses low-temperature-coefficient resistance paste for a potentiometer and a preparation method of the low-temperature-coefficient resistance paste. The resistance paste is composed of a conductive phase, a glass phase and an organic carrier, the conductive phase is bismuth ruthenate nanowires and carbon-coated copper nanowires, the glass phase comprises Bi2O3, B2O3, SiO2 and La2O3, and the organic carrier is composed of ethyl cellulose and terpilenol. The preparation method comprises the following steps: respectively preparing the components, mixing in proportion, and rolling by a three-roller mill. The TCR value of a resistive layer formed by the paste is controlled to be + / -50 ppm / DEG C, the resistance change is lower than 0.8% after 1000 times of-55-125 DEG C cold and hot cycles, low-temperature sintering can be achieved, the silver migration resistance is excellent, the high-frequency insertion loss of the 3GHz frequency band is low, the sheet resistance uniformity is good, and the paste is suitable for the miniaturization, high precision and high-frequency scene requirements of high-end potentiometers.