CN111394687B

CN111394687B - Coating method of carbon nano material on metal surface and electrochemical application

Info

Publication number: CN111394687B
Application number: CN202010327899.3A
Authority: CN
Inventors: 王夏; 邬慧
Original assignee: Nanjing Kelaifeien New Material Technology Co ltd
Current assignee: Nanjing Kelaifeien New Material Technology Co ltd
Priority date: 2020-04-23
Filing date: 2020-04-23
Publication date: 2022-04-19
Anticipated expiration: 2040-04-23
Also published as: CN111394687A

Abstract

The invention relates to a coating method and electrochemical application of a carbon nano material on a metal surface, wherein the carbon nano material is uniformly dispersed on the metal surface through electrostatic adsorption to form a highly ordered carbon nano coating, then the carbon nano coating is calcined at high temperature for 1-2 h under strict anaerobic condition, then the temperature is instantly reduced to 350 ℃, saturated steam containing carbon dioxide is added to ensure that carbon atoms are rearranged and recrystallized on the original sites, and the highly ordered carbon/metal alloy nano coating is formed on the metal surface. The carbon nano material is used as a precursor, is deposited on the metal surface by utilizing electrostatic adsorption, and is calcined and rapidly cooled to finally form a carbon/metal alloy nano coating on the metal surface.

Description

Coating method of carbon nano material on metal surface and electrochemical application

Technical Field

The invention belongs to the technical field of nano material coating, and particularly relates to a coating method of a carbon nano material on a metal surface and electrochemical application.

Background

The nano material is a general name of zero-dimensional, one-dimensional, two-dimensional and three-dimensional materials which are composed of ultrafine particles with the size of less than 100nm (0.1-100 nm) and have small size effect. The concept of nano materials is formed in the middle of the 80 s, and as the nano materials can show specific optical, electrical, magnetic, thermal, mechanical and mechanical properties, the nano technology is rapidly applied to various fields of materials, and becomes a hot spot of scientific research in the world at present. One application is a nano material coating which is used for surface modification, cladding, modification or adding new characteristics, and the excellent characteristics of the nano material are utilized to improve the performance of the coated material. At present, most of the existing nano material coating methods adopt a machine spraying technology, the binding property with the coated material is poor, and the performance is unstable.

In addition, the core component of the anion generator is a release head, which mainly comprises three types of metal needle tip release heads, carbon fiber brush release heads and fullerene modified metal release heads at present. The generation principle of all the release heads is to simulate the lightning in the forest and generate negative oxygen ions in the high-concentration oxygen atmosphere, namely under the action of given negative high voltage, an uneven electric field is generated between the release heads and a flat plate electrode, and a large amount of electrons are released by generating high-voltage corona. Because oxygen molecules are rich in electrons in the air, the released electrons are captured by the oxygen molecules, and negative oxygen ions, called negative ions for short, are formed. The main factors limiting the generation of negative ions are three: one is the high and low of the negative voltage; one is the density of the release head; one is the conductivity or internal resistance of the release head. Two factors influence the migration distance of the negative ions, one is the magnitude of the negative voltage (initial kinetic energy) and the other is the stiffness of the release head (low dissociation threshold). The first release heads were needle-type, often cylindrical steel or other metal needles, with good electrical conductivity (resistivity 10-8 ρ/Ω · m), but affected by high voltage corrosion factors, often with metals with relatively high melting points, such as molybdenum or tungsten wires. However, due to the limitation of forming processing, the metal needle release head is difficult to take into account two factors of high density and rigidity, thereby influencing the release concentration of negative ions. The carbon fiber brush release head takes carbon fibers as the release head, has the advantages of high density, softness and uneasy injury of the fibers, and has the defects of high resistivity, generally only 10-5 rho/omega.m, complex manufacturing process, easy adsorption of oil smoke and dust, uneasy cleaning, long-term performance degradation and influence on the use efficiency. The high dissociation threshold means that electrons break through the constraint of the metal surface and need to reach the metal surface at a higher voltage, thereby influencing the generation amount of negative ions. At present, the fullerene C60 is used as a functional material to modify a metal wire so as to prepare a negative ion release head. The fullerene is fully utilized as a high-conductivity characteristic (the resistivity is only 1/6 of metallic copper), and the fullerene is dispersed in a nanometer scale, so that the unit density of a release site is maximized, the anion release technology is pushed to a new height, and the purification effect is often higher than that of the traditional release head by one order of magnitude. However, the release heads prepared by this method still have two drawbacks, one being that the fullerene has poor adhesion and often requires a binder to bond the metal wire, which undoubtedly increases the internal resistance and raises the electron dissociation threshold. One is that fullerene is greatly influenced by factors such as ozone and ultraviolet, and can be stripped after long-time operation under negative high pressure, so that the concentration of negative ions is attenuated. Therefore, the anion releasing heads available in the market are limited by the defects of difficult manufacturing process, low concentration of released anions, poor effect, short service life and the like, and further upgrading and reconstruction are needed. How to keep two main characteristics of carbon materials such as fullerene C60, namely high release density and high conductivity, and simultaneously, the compatibility with metal is considered, and the rigidity is improved, becomes a research hotspot.

Disclosure of Invention

In order to solve the technical problems in the prior art, the invention aims to provide a coating method of a carbon nano material on a metal surface and electrochemical application.

In order to achieve the purpose and achieve the technical effect, the invention adopts the technical scheme that:

step one, cleaning the metal surface

Step two, electrostatic repulsion dispersion

Carbon nano particles are taken as a precursor, a negative electrostatic field is introduced to load electrostatic negative charges on the carbon nano particles, and the carbon nano particles are freely and highly dispersed in the reactor based on the electrostatic like repulsion principle;

step three, electrostatic deposition adsorption

The method comprises the following steps of (1) electrifying electrostatic positive charges to metal, so that carbon nano particles loaded with the electrostatic negative charges are rapidly deposited on the surface of the metal under the action of electrostatic attraction to form a highly ordered carbon nano coating, wherein the thickness of the carbon nano coating is adjustable and is controlled by the ratio of positive voltage loaded on the surface of the metal to negative voltage loaded on the carbon nano particles, and the larger the ratio is, the thicker the carbon nano coating is;

step four, high-temperature sintering

Placing the metal adsorbing the carbon nano particles into a high-temperature sintering furnace, gradually heating to 1520-1850 ℃, sintering at high temperature for 1-2 hours, wherein the high-temperature sintering furnace requires oxygen insulation or argon protection, the initial oxygen concentration is less than 1.0ppm, the carbon nano particles are locally cracked and collapsed, but the basic positions are unchanged, and at the temperature, part of carbon atoms of the carbon nano particles are activated and permeate into the metal surface, so that local carbonization of the metal surface is formed;

step five, alloying metal

Rapidly cooling to a medium-low temperature zone (350 ℃), forming nano-scale local cavities on the metal surface, forming carbon-metal alloy with distorted carbon atoms infiltrated therein, maintaining the basic sites and basic appearance of carbon atoms not infiltrated in the carbon nanoparticles unchanged, then adding a coolant, enhancing the cooling speed, enabling the carbon atoms to be rearranged and recrystallized on the original sites, and forming a highly-ordered carbon/metal alloy nano-coating on the metal surface to obtain the carbon/metal alloy.

Further, in the second step, the carbon nanoparticles are placed into a reactor, a negative electrostatic field is introduced into the reactor, the voltage of the negative electrostatic field is-120V, the vacuum degree of the reactor after vacuumizing is not higher than 20Pa, the volume concentration of the carbon nanoparticles in the reactor is not more than 0.3%, the carbon nanoparticles are used as micro suspended matters in the reactor to form highly dispersed carbon nanoparticles carrying electrostatic negative charges, and the dispersion time is more than 30min, so that the high dispersion and the uniform charging are facilitated.

Further, in the third step, metal is placed into a reactor, the metal is insulated from the reactor, after the carbon nano particles load electrostatic negative charges, a positive electrostatic field is applied to the metal, the electrostatic voltage is + 100V-12000V, so that the metal is loaded with electrostatic positive charges, the carbon nano particles loaded with the negative charges are deposited on the surface of the metal, a carbon nano coating is obtained, the thickness of the carbon nano coating is 0.72-0.80 nm, the electrostatic deposition temperature is 80-120 ℃, the electrostatic deposition time is not less than 30min, then the negative electrostatic field on the reactor is removed, then the positive electrostatic field on the metal is removed, the metal is taken out of the reactor, and the metal is transferred into a high-temperature sintering furnace.

Further, in the fourth step, the high-temperature sintering furnace is a rotary furnace, and precise temperature control is required.

Further, in the fifth step, the coolant is saturated water vapor containing carbon dioxide, and the saturated water vapor containing carbon dioxide is rapidly and uniformly added into the high-temperature sintering furnace.

Further, the metal is a tungsten-gold wire, and the step of cleaning the surface of the tungsten-gold wire comprises the following steps:

soaking the tungsten-gold wire in an acetone solution for 10 hours, then taking out, cleaning with absolute ethyl alcohol to remove adhesive substances, dust and the like on the surface of the tungsten-gold wire, washing with deionized water for 3-5 times, and drying at 100-120 ℃ for later use.

Further, the carbon nanoparticles are one of fullerene C60, C70, CNTs and AGNRs.

The invention also provides an application of the coating method of the carbon nano material on the metal surface in electrochemistry.

The invention also provides application of the coating method of the carbon nano material on the metal surface in preparation of the negative ion release head.

The invention also provides application of the coating method of the carbon nano material on the metal surface in preparing the capacitor coating plate.

The invention also provides application of the coating method of the carbon nano material on the metal surface in preparing the ceramic plate of the ozone generator.

Compared with the prior art, the invention has the beneficial effects that:

the invention discloses a coating method and electrochemical application of carbon nano materials on a metal surface, which comprises the steps of uniformly dispersing carbon nano materials such as fullerene and the like on the metal surface of a tungsten gold wire and the like by an electrostatic adsorption method under a vacuum condition to form a highly ordered carbon nano coating, then carrying out high-temperature calcination for 1-2 h under a strict anaerobic condition, then instantly cooling to 350 ℃, adding saturated water vapor containing carbon dioxide to ensure that carbon atoms are rearranged and recrystallized on original sites, and forming the highly ordered carbon/metal alloy nano coating on the metal surface. The invention provides a coating method of carbon nano-materials on a metal surface and electrochemical application, which utilizes the structural order of regular carbon nano-materials such as fullerene, and the like, and directional and ordered arrangement, takes carbon nano-particles such as fullerene C60, C70, CNTs, AGNRs, and the like as precursors, deposits on the metal surface by utilizing the electrostatic adsorption effect, then locally carbonizes the metal surface by calcination, and finally forms a highly regular and ordered carbon/metal alloy nano-coating on the metal surface by recrystallization of the carbon nano-particles on the metal surface after rapid cooling.

Drawings

FIG. 1 is a schematic structural view of example 1 of the present invention;

FIG. 2 is a diagram showing the preparation of a carbon nanocoating according to example 1 of the present invention;

FIG. 3 is a diagram illustrating the preparation of a carbon/tungsten alloy nanocoating according to example 1 of the present invention;

FIG. 4 is a flow chart of the preparation of example 1 of the present invention;

wherein, 1-anion carbon/tungsten alloy tows; 2-a metal fixing jacket; 3-insulating hot-melt shrinkage pipe; 4-a conductive rod; 5-an electrochemical anti-corrosion paint layer; 6-conductive hot melt adhesive; 7-tungsten gold wire; 8-carbon nanocoating; 9-carbon/tungsten alloy nanocoating.

Detailed Description

The embodiments of the present invention will be described in detail with reference to the accompanying drawings so that the advantages and features of the invention can be more easily understood by those skilled in the art, and the scope of the invention will be clearly and clearly defined.

A method for coating a carbon nano material on a metal surface comprises the following steps:

step one, cleaning the metal surface

Step two, electrostatic repulsion dispersion

step three, electrostatic deposition adsorption

step four, high-temperature sintering

step five, alloying metal

And in the second step, putting the carbon nanoparticles into a reactor, introducing a negative electrostatic field on the reactor, wherein the voltage of the negative electrostatic field is-120V, the vacuum degree of the reactor after vacuumizing is not higher than 20Pa, the volume concentration of the carbon nanoparticles in the reactor is not more than 0.3%, the carbon nanoparticles are used as micro suspended matters in the reactor to form highly dispersed carbon nanoparticles carrying electrostatic negative charges, and the dispersion time is more than 30min so as to facilitate high dispersion and uniform charge.

And step three, putting metal into a reactor, insulating the metal from the reactor, introducing a positive electrostatic field to the metal after the carbon nanoparticles are loaded with electrostatic negative charges, introducing a positive electrostatic field to the metal, loading electrostatic positive charges on the metal by electrostatic voltage of + 100V-12000V, depositing the carbon nanoparticles loaded with the negative charges on the surface of the metal to obtain a carbon nano coating, wherein the thickness of the carbon nano coating is 0.72-0.80 nm, the electrostatic deposition temperature is 80-120 ℃, the electrostatic deposition time is not less than 30min, then removing the negative electrostatic field on the reactor, then removing the positive electrostatic field on the metal, taking the metal out of the reactor, and transferring the metal into a high-temperature sintering furnace.

In the fourth step, the high-temperature sintering furnace is a rotary furnace, and precise temperature control is required.

And fifthly, the coolant is saturated steam containing carbon dioxide, and the saturated steam containing carbon dioxide is quickly and uniformly added into the high-temperature sintering furnace.

The carbon nano-particles are one of fullerene C60, C70, CNTs and AGNRs.

The invention also discloses application of the coating method of the carbon nano material on the metal surface in preparation of negative ion release heads, capacitor coating plates, ozone generator electrostatic ceramic plates and other electrochemistry.

Example 1

As shown in fig. 1 to 4, a method for coating a carbon nanomaterial on a metal surface comprises the following steps:

step one, surface cleaning of tungsten gold wire

Soaking the gold tungsten wire 7 in an acetone solution for 10 hours, taking out, cleaning with absolute ethyl alcohol to remove adhesive substances, dust and the like on the surface of the gold tungsten wire 7, washing with deionized water for 3-5 times, and drying at 120 ℃ for later use;

step two, electrostatic repulsion dispersion

The fullerene C60 carbon nano material is used as a precursor, electrostatic negative charges are loaded, and the fullerene C60 particles are freely and highly dispersed in a vacuumized reactor due to the electrostatic isotropic repulsion principle, the electrostatic voltage is-100V-120V, the vacuum degree of the vacuumized reactor is not higher than 20Pa, and the volume concentration of the carbon nano material in the reactor is not easy to exceed 0.3%;

step three, electrostatic deposition adsorption

The positive electrostatic charge is introduced to the tungsten-gold wire 7, the electrostatic voltage is + 100V-12000V, the fullerene C60 precursor loaded with the negative charge is rapidly deposited on the surface of the tungsten-gold wire 7 due to electrostatic attraction to break electrostatic repulsion, and a uniform carbon nano coating 8 with the thickness of 0.72-0.80 nm is formed, the coating thickness can be controlled by the times of the positive voltage loaded on the tungsten-gold wire 7 to the negative voltage loaded on the carbon nano material, the larger the times, the thicker the carbon nano coating 8, the more the number of layers, and the maximum thickness of the carbon nano coating can reach 72-80 nm;

step four, high-temperature sintering

Placing the tungsten-gold wire 7 adsorbed with the fullerene C60 carbon nano material into a high-temperature sintering furnace, gradually heating to 1600 ℃, wherein the high-temperature sintering furnace requires oxygen insulation, the initial oxygen concentration is less than 1.0ppm, the carbon nano material is locally cracked and collapsed after being sintered for 1h, but the basic position is unchanged, and at the temperature, part of carbon atoms of the fullerene C60 carbon nano material can actively permeate into the surface of the tungsten-gold wire, so that the local carbonization of the metal surface is formed;

step five, carbon/tungsten alloying

Under the condition of high temperature, the tungsten gold is a catalyst for cooling, reforming and depositing the carbon nano material; after the fourth step is finished, rapidly cooling the tungsten-gold wire 7 to 350 ℃, forming nano-scale local cavities on the surface, forming carbon/tungsten alloy with distorted carbon atoms infiltrated therein, keeping the basic sites and basic appearance of the remaining carbon atoms of the carbon nano material unchanged, adding saturated water vapor containing carbon dioxide, enhancing the cooling speed, enabling the carbon nano atoms to be rearranged and recrystallized on the original sites, thereby forming a highly-normalized and ordered carbon/tungsten alloy nano coating 9 on the surface of the tungsten-gold wire 7, finally obtaining the carbon/tungsten alloy wire, and assisting the carbon-carbon atomic bonds to be reconstructed among the carbon atoms while rapidly vaporizing the carbon dioxide to take away a large amount of heat, thereby maintaining the bonding fastness of the carbon nano coating and maintaining the covalent bond bonding.

And in the second step, putting the fullerene C60 carbon nano-particles into a reactor, and introducing a negative electrostatic field on the reactor, wherein the voltage of the electric field is basically between-100 and 120V, so that the fullerene C60 carbon nano-particles are used as tiny suspended matters in the reactor to form highly dispersed carbon nano-particles carrying negative charges, namely 'aerosol', and the dispersion time is stabilized to be more than 30min so as to facilitate high dispersion and uniform charge.

In the third step, the tungsten gold wire 7 is also placed into a reactor, the tungsten gold wire 7 is insulated from the reactor, after carbon nano particles of fullerene C60 form negative charge aerosol, positive charge is introduced to the tungsten gold wire 7, the voltage is controlled to be adjustable between 120V and 12000V, the electrostatic deposition temperature is 80-120 ℃, the electrostatic deposition time is not less than 30min, a highly ordered carbon nano coating 8 is formed on the surface of the tungsten gold wire, the thickness of the carbon nano coating 8 is adjustable, the carbon nano coating 8 is thicker under the control of the ratio of positive voltage loaded on the surface of the metal tungsten gold wire 7 to negative voltage loaded on the carbon nano particles, after the growth of the carbon nano coating 8 is completed, the negative electric field on the reactor is firstly removed, then the positive electric field on the tungsten gold wire 7 is removed, the tungsten gold wire 7 is taken out from the reactor and is transferred to a high-temperature calcining furnace.

And in the fourth step, the high-temperature sintering furnace is a rotary furnace, so that the sintering temperature is uniform and controllable, precise temperature control is required, the temperature in the high-temperature sintering furnace is controlled to be enough to locally disintegrate the carbon nano material, and the carbon nano material is easily vaporized at an over-high temperature, so that the formation of a coating is not facilitated.

And step five, when the temperature is quickly reduced to 350 ℃, quickly injecting saturated steam containing carbon dioxide into the high-temperature calcining furnace, wherein the rapidness and uniformity are the key of the process control at the stage, the rearrangement of carbon atoms is slowed down when the temperature is too low, and the deposition and reforming of the carbon nano material are not facilitated when the temperature is too high.

The carbon/tungsten alloy nano coating 9 is a superconducting material with the resistance close to zero, the resistivity is only 1/6 of brass, the ordered carbon/tungsten alloy nano coating 9 is used as a coating layer, the electronic dissociation threshold can be greatly reduced, the numerical value of negative high voltage release is reduced, the comfort level of a human body is improved, the ionization and the precipitation of electric ions are facilitated, high-quality negative oxygen ions with small particle size, high activity and long migration distance can be generated, the purity of the negative ions is high, and byproducts such as ozone, nitrogen oxides, positive ions and the like are hardly generated.

The carbon/tungsten alloy nano coating 9 is made of one or a combination of fullerene C60, a C70 layer, a Carbon Nano Tube (CNTs) layer and a chair-type graphene nanoribbon (AGNRs) layer, and can form one or more layers, and the thickness of the carbon/tungsten alloy nano coating 9 is 2-50 nm.

The invention also discloses an application of the coating method of the carbon nano material on the metal surface in preparing the negative ion release head, the negative ion release head comprises a negative ion carbon/tungsten alloy filament bundle 1, a metal fixing jacket 2, a conductive wire, an insulating hot melt shrinkage pipe 3 and a conductive rod 4, the negative ion carbon/tungsten alloy filament bundle 1 is fixed around the conductive rod 4 through the metal fixing jacket 2 and is uniformly distributed, the negative ion carbon/tungsten alloy filament bundle 1 is ensured to be fully contacted with the conductive rod 4, no internal resistance is generated, the conductive wire is inserted into the carbon/tungsten alloy release filament bundle 1, a conductive hot melt adhesive 6 is filled in gaps among the carbon/tungsten alloy release filament bundle 1, the conductive rod 4 and the metal fixing jacket 2, the outer surfaces of the conductive rod 4 and the metal fixing jacket 2 are respectively coated with an electrochemical anti-corrosive paint layer 5, the insulating hot melt shrinkage pipe 3 is coated outside the metal fixing jacket 2, the heating shrinkage is integrated with the metal fixing jacket 2, on one hand, the electrostatic interference between each conductive part can be prevented, on the other hand, the fixing firmness between the negative ion carbon/tungsten alloy wire beam 1 and the conductive rod 4 can be improved, and the internal resistance is reduced.

The anion carbon/tungsten alloy filament bundle 1 is provided with a highly-regularized and ordered carbon/tungsten alloy nano coating prepared by a coating method of carbon nano materials on the metal surface, and then the anion carbon/tungsten alloy filament bundle 1 is prepared. Carbon materials such as fullerene C60 and the like are added to further improve and increase the negative ion release sites, thereby releasing higher negative ion concentration, in order to solve the problems of durability and non-ultraviolet resistance, the carbon nano material is infiltrated into the inner part of the surface of the tungsten-gold wire by the electrostatic adsorption technology, thereby realizing carbon/tungsten alloying, simultaneously reserving the site and structure when the carbon material is initially adsorbed, namely nano ordering, the carbon nano interface layer after doping and reforming retains the high conductivity of the fullerene, meanwhile, the alloy has rigidity, can effectively reduce and release high voltage, inhibit ozone derivatives generated when negative ions are generated by discharge, the particle diameter of the negative ions generated by the release head is small, the release head not only can remove PM2.5, but also has the effects of sterilizing and disinfecting and removing VOCs (volatile organic compounds), and in addition, due to the electronegativity, can exert biological effect by penetrating blood brain barrier of human body, and has certain antioxidant and antiaging effects.

The metal fixing jacket 2 is a metal rivet fixing structure for connecting the carbon/tungsten release head and the conducting rod 4, and is preferably a conducting metal strip, and the conducting metal strip is preferably a brass strip. The metal fixing jacket 2 is made of metal materials, so that the metal fixing jacket is good in conductivity, good in flexibility and easy to compact. The metal fixing jacket 2 replaces the traditional welding mode to fix the conductive wire and fix the conductive wire by the insulating hot-melting shrinkage tube 3, so that the problems of loosening, falling and the like of the negative ion carbon/tungsten alloy wire bundle 1 can be avoided, the high-conductivity characteristic is kept, and the service life of the release head is prolonged.

The conducting rod 4 is a metal screw rod and is made of red copper.

The conductive hot melt adhesive is composed of nano silver composite resin, and not only can the fixing firmness between the negative ion carbon/tungsten alloy filament bundle 1 and the conductive rod 4 be improved, but also the conductivity can be improved.

The electrochemical anti-corrosion paint layer 5 is inorganic insulating glue.

The negative ion carbon/tungsten alloy filament bundle 1 is composed of a plurality of tungsten wires 7, the tungsten content in the tungsten wires 7 can be more than 99%, the length of each tungsten wire 7 is 1-3 cm, and the diameter of each tungsten wire 7 is 0.1-0.2 mm.

The plurality of conductive wires are made of the same or different materials, and the negative ion release head comprises 40-60 negative ion carbon/tungsten alloy tows 1.

The negative ion carbon/tungsten alloy wire bundle 1 consists of a plurality of carbon/tungsten alloy wires 7. The tungsten gold wire 7 has good conductivity, heat resistance and corrosion resistance, is convenient to process and has low price; the tungsten gold wire 7 has the characteristics of silence, grease resistance, dirt resistance and corrosion resistance, the negative ion generation amount is large, byproducts such as ozone and nitric oxide are hardly generated, dust and particles are not easily adsorbed on the surface, and frequent cleaning is not needed.

A method for preparing an anion releasing head comprises the following steps:

step 1, preparing a carbon/tungsten alloy wire;

step 2, bundling and cutting a plurality of carbon/tungsten alloy wires to generate negative ion carbon/tungsten alloy tows 1;

step 3, inserting the conductive wire into the carbon/tungsten alloy wire bundle 1, fixing the part of the negative ion carbon/tungsten alloy wire bundle 1, which is connected with the conductive wire, through a metal fixing jacket 2, and electrically connecting the negative ion carbon/tungsten alloy wire bundle 1 with a conductive rod 4;

step 4, conducting resin sliding: and a gap between the conductive wire, the metal fixing jacket 2 and the negative ion carbon/tungsten alloy wire bundle 1 is filled with a conductive hot melt adhesive 6.

And 5, coating an electrochemical anti-corrosion paint layer 5 on the outer parts of the conductive wires and the metal fixing jacket 2, sealing by using an insulating hot-melt shrinkage pipe 3, and connecting with electricity.

Example 2

As shown in fig. 1 to 4, a method for preparing a negative ion emitting head includes the steps of:

the conducting rod 4 is a red copper rod; the metal fixing jacket 2 is a brass strip; the negative ion carbon/tungsten alloy release tow 1 comprises 40 tungsten gold wires, wherein each tungsten gold wire is deposited with a fullerene C60 carbon/tungsten alloy nano coating with the thickness of 10nm and is subjected to high-temperature sintering and reforming, and the length of each tungsten gold wire is 1cm, and the diameter of each tungsten gold wire is 0.1 mm. The gaps among the metal fixing jacket 2, the carbon/tungsten alloy release tows 1 and the conducting rod 4 are filled with conductive hot melt adhesive 6, the outsides of the metal fixing jacket 2 and the conducting rod 4 are coated with an electrochemical anti-corrosion paint layer 5, the outsides of the fixing jacket 6 are coated with insulating hot melt shrinkage pipes 3, and the insulating hot melt shrinkage pipes 3 are adopted for sealing.

Example 3

As shown in fig. 1 to 4, a method for preparing a negative ion emitting head includes: the conducting rod 4 is a red copper rod; the metal fixing jacket 2 is a brass strip; the anion carbon/tungsten alloy release tow 1 comprises 40 tungsten wires, each tungsten wire is deposited with a CNTs carbon/tungsten alloy nano coating with the thickness of about 20nm and is subjected to high-temperature sintering and reforming, the tungsten content in the tungsten wire is 99.5%, the length of the tungsten wire is 2cm, and the diameter of the tungsten wire is 0.2 mm. The gaps among the metal fixing jacket 2, the carbon/tungsten alloy release tows 1 and the conducting rod 4 are filled with conductive hot melt adhesive 6, the outsides of the metal fixing jacket 2 and the conducting rod 4 are coated with an electrochemical anti-corrosion paint layer 5, the outsides of the fixing jacket 6 are coated with insulating hot melt shrinkage pipes 3, and the insulating hot melt shrinkage pipes 3 are adopted for sealing.

Example 4

As shown in fig. 1 to 4, a method for preparing a negative ion emitting head includes: the conducting rod 4 is a brass rod; the metal fixing jacket 2 is a copper strip; the anion carbon/tungsten alloy release tow 1 comprises 60 tungsten gold wires, wherein an AGNRs layer with the thickness of about 30nm is deposited on each tungsten gold wire, and the AGNRs layer is subjected to high-temperature sintering and reforming, the tungsten content in the tungsten gold wires is 99.5%, the length of the tungsten gold wires is 2cm, and the diameter of the tungsten gold wires is 0.2 mm. The gaps among the metal fixing jacket 2, the carbon/tungsten alloy release tows 1 and the conducting rod 4 are filled with conductive hot melt adhesive 6, the outsides of the metal fixing jacket 2 and the conducting rod 4 are coated with an electrochemical anti-corrosion paint layer 5, the outside of the metal fixing jacket 2 is coated with an insulating hot melt shrinkage pipe 3, and the insulating hot melt shrinkage pipe 3 is adopted for sealing.

Comparative example 1

An anion releasing head is commercially available, which only uses a metallic tungsten gold wire as a discharge material, and the releasing head is not coated with the carbon/tungsten alloy nano-coating 9.

Performance testing

1. Anion release test

1) Testing instrument

Hand-held atmospheric negative ion tester-manufacturer: hua Si Tong; the instrument model is as follows: WST-3200 Pro.

2) Test conditions

Temperature: 18 deg.C

Relative humidity: 18 percent;

PM2.5：30μg/m³

3) test procedure

The conductive rod 4 was energized with a voltage of 20kV, and the tester, with the hand of the atmospheric negative ion tester, stood right in front of the negative ion emitting head to be tested, in a direction deviated 22.5 ° to the left, in a direction deviated 22.5 ° to the right, and at positions respectively distant from the negative ion emitting head by 1m, and tested the amounts of negative ions emitted from the emitting heads obtained in examples 2 to 4 of the present invention and the emitting head of comparative example 1.

4) Test results

The test results of the negative ion emitting heads of examples 2 to 4 and comparative example 1 are shown in table 1, and the left, center and right in table 1 represent the directions of 22.5 ° left, 22.5 ° right and front of the negative ion emitting head, respectively.

TABLE 1

As can be seen from Table 1, all the discharge heads of examples 2 to 4 of the present invention had a large increase in the anion concentration of 1.0m as compared with the discharge head of comparative example 1, indicating that the use of the discharge heads of examples 2 to 4 of the present invention is effective in increasing the anion discharge concentration.

TABLE 2

As can be seen from Table 2, all the release heads of examples 2 to 4 of the present invention also have a large increase in the anion concentration of 3.0m as compared with the release head of comparative example 1, and it can be seen from the comparison between Table 1 and Table 2 that the release heads of the examples of the present invention still have a strong anion concentration at a far distance, which proves that the method of the present invention has a certain universality and can significantly improve the migration distance of anions.

The carbon/tungsten alloy coating prepared by the invention is used as a functional layer to be coated on the surface of the gold tungsten wire 7, is durable in use, and has no attenuation of the concentration of negative ions; the density of the negative ion generating sites is high, and the generating amount is large; the electron dissociation threshold is low, the particle size of negative ions is smaller, and the power is lower; the tungsten gold wire with the highest melting point is used, so that the corrosion resistance is realized, and the bonding strength with the carbon material is high; the internal resistance is extremely low, no thermal conversion is generated, and no ozone is generated; the rigidity of the negative ion generation site is strong, and the negative ions move farther.

The parts of the invention not described in detail can be realized by adopting the prior art, and are not described herein.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A method for coating a carbon nano material on a metal surface is characterized by comprising the following steps:

step one, cleaning the metal surface

Step two, electrostatic repulsion dispersion

step three, electrostatic deposition adsorption

step four, high-temperature sintering

Placing the metal adsorbing the carbon nano particles into a high-temperature sintering furnace, gradually heating to 1520-1850 ℃, sintering at high temperature for 1-2 hours, wherein the high-temperature sintering furnace requires oxygen insulation, the initial oxygen concentration is less than 1.0ppm, the carbon nano particles are locally cracked and collapsed, but the basic positions are unchanged, and at the temperature, part of carbon atoms of the carbon nano particles are activated and permeate into the metal surface, so that local carbonization of the metal surface is formed;

step five, alloying metal

And (3) rapidly cooling to a medium-low temperature region, forming nano-scale local cavities on the metal surface, forming carbon-metal alloy with distorted carbon atoms infiltrated therein, keeping the basic sites and basic appearance of carbon atoms not infiltrated in the carbon nanoparticles unchanged, adding a coolant, enhancing the cooling speed, rearranging and recrystallizing the carbon atoms on the original sites, and forming a highly-ordered carbon/metal alloy nano-coating on the metal surface to obtain the carbon/metal alloy.

2. The method for coating the carbon nano-material on the metal surface according to claim 1, wherein in the second step, the carbon nano-particles are placed into a reactor, a negative electrostatic field is applied to the reactor, the voltage of the negative electrostatic field is-120 to 120V, the vacuum degree of the reactor after vacuumizing is not higher than 20Pa, the volume concentration of the carbon nano-particles in the reactor is not more than 0.3 percent, the carbon nano-particles are used as micro suspended matters in the reactor to form highly dispersed carbon nano-particles carrying electrostatic negative charges, and the dispersion time is more than 30min, so that the high dispersion and the uniformity of the charges are realized.

3. The method for coating carbon nano-materials on the metal surface according to claim 1, wherein in the third step, the metal is placed in a reactor, the metal is insulated from the reactor, after the carbon nano-particles are loaded with electrostatic negative charges, a positive electrostatic field is applied to the metal, the electrostatic voltage is + 100V-12000V, so that the metal is loaded with electrostatic positive charges, the carbon nano-particles loaded with negative charges are deposited on the metal surface, and the carbon nano-coating is obtained, wherein the thickness of the carbon nano-coating is 0.72-0.80 nm, the electrostatic deposition temperature is 80-120 ℃, the electrostatic deposition time is not less than 30min, then the negative electrostatic field on the reactor is firstly removed, then the positive electrostatic field on the metal is removed, and the metal is taken out of the reactor and transferred into a high-temperature sintering furnace.

4. The method for coating the carbon nano-material on the metal surface according to the claim 1, wherein in the fourth step, the high-temperature sintering furnace is a rotary furnace, and precise temperature control is required.

5. The method for coating the carbon nano-material on the metal surface according to the claim 1, wherein in the fifth step, the coolant is saturated water vapor containing carbon dioxide, and the saturated water vapor containing carbon dioxide is rapidly and uniformly added into the high-temperature sintering furnace.

6. The method for coating the carbon nano-material on the metal surface according to claim 1 or 3, wherein the metal is a gold tungsten wire, and the step of cleaning the surface of the gold tungsten wire comprises the following steps:

soaking the tungsten-gold wire in an acetone solution, taking out, cleaning with absolute ethyl alcohol to remove adhesive substances on the surface of the tungsten-gold wire, washing with deionized water for 3-5 times, and drying at 100-120 ℃ for later use.

7. The method as claimed in any one of claims 1 to 3, wherein the carbon nanoparticles are one of fullerenes C60, C70, CNTs, AGNRs.

8. Use of the method for coating a metal surface with a carbon nanomaterial according to any one of claims 1 to 5 in the preparation of a negative ion-emitting head.

9. Use of a method of coating a metal surface with a carbon nanomaterial according to any of claims 1 to 5 in the preparation of a capacitor plate.

10. Use of a method of coating a metal surface with a carbon nanomaterial according to any of claims 1 to 5 in the preparation of a ceramic plate for an ozone generator.