Disclosure of Invention
The invention aims to solve the technical problem of providing a composite metal wire with a composite electroplated nanocarbon metal film and a preparation method thereof, and realizing large-batch continuous preparation of high-conductivity composite metal wires.
In order to solve the above problems, the present invention provides a composite metal wire having a composite plated nanocarbon metal film and a method for preparing the same, and provides a metal wire; dispersing the dispersed nano carbon powder and metal salt in a solvent to prepare a composite electroplating solution; and continuously passing the metal wire through the composite electroplating solution in a roll-to-roll transmission mode, and simultaneously carrying out composite electroplating treatment on the surface of the metal wire to form a nano carbon metal film covering the surface of the metal wire, wherein at least part of nano carbon in the nano carbon metal film is connected through metal, and the composite electroplating treatment comprises electrophoretic deposition and electroplating deposition which are carried out simultaneously.
Optionally, in the composite electroplating treatment process, the metal wire is connected to a cathode, an anode metal plate is arranged in the composite electroplating solution, and the material of the anode metal plate and the metal cations in the composite electroplating solution are the same metal.
Optionally, the metal wire includes a metal wire substrate and a graphene layer deposited on a surface of the metal wire substrate.
Optionally, the method for forming the graphene layer includes: and transmitting the metal wire substrate between a roll-to-roll input end and a roll-to-roll output end by using a roll-to-roll deposition mode, and depositing the graphene layer on the surface of the metal wire substrate by using a plasma enhanced chemical vapor deposition process in the transmission process of the metal wire substrate.
Optionally, the deposition temperature of the plasma enhanced chemical vapor deposition process is 700-850 ℃, the radio frequency power is 5-200W, the adopted deposition gas comprises C, H element-containing gas, the flow rate of the deposition gas is 1-50 sccm, and the growth time of the graphene layer is 30-60 min.
Optionally, the length of the metal wire substrate is more than 1m, the diameter of the metal wire substrate is 10-500 μm, and the graphene layer includes 1-10 layers of graphene.
Optionally, the solvent in the composite plating solution includes at least one of ethanol and acetone.
Optionally, the concentration range of the nanocarbon in the composite electroplating solution is 0.1-0.9 g/L, and the concentration range of the metal salt is 0.02-0.8 mol/L.
Optionally, the current density during the composite electroplating treatment is 0.4-8A/cm2。
Optionally, when the surface of the metal wire is subjected to composite electroplating treatment, the distance between the metal wire and the anode is 4-20 cm, the applied electric field strength is 20-40V/cm, and the transmission speed of the metal wire is 0.05-0.5 m/s.
Optionally, the method for obtaining the dispersed nanocarbon powder includes: and shearing and dispersing the nano carbon, carrying out acid washing treatment by adopting a mixed solution of concentrated nitric acid and concentrated hydrochloric acid, diluting the nano carbon into neutrality by using deionized water, and drying the nano carbon to obtain the dispersed nano carbon powder.
Optionally, the nanocarbon comprises one or more of single-walled carbon nanotubes, multi-walled carbon nanotubes, graphene and derivatives thereof; the metal in the metal salt comprises one or more of Cu, Ni, Ru, Co and Ta.
The technical scheme of the invention also provides a composite metal wire with composite electroplated nano metal carbon, which comprises the following steps: a metal wire; and the nano carbon metal film covers the surface of the metal wire, and at least part of nano carbon in the nano carbon metal film is connected through metal.
Optionally, the metal wire includes a metal wire substrate and a graphene layer deposited on a surface of the metal wire substrate.
Optionally, the graphene layer is a plasma enhanced chemical vapor deposition layer.
Optionally, the length of the metal wire substrate is more than 1m, and the diameter of the metal wire substrate is 10-500 μm; the graphene layer comprises 1-10 layers of graphene.
Optionally, the nanocarbon in the nanocarbon metal film comprises one or more of a single-walled carbon nanotube, a multi-walled carbon nanotube, graphene and derivatives thereof.
Optionally, the metal in the nanocarbon metal film comprises one or more of Cu, Ni, Ru, Co and Ta.
According to the forming method of the composite metal wire, disclosed by the invention, the metal wire is subjected to composite electroplating to form a nano carbon metal film on the surface of the metal wire in the process of conveying the metal wire in a roll-to-roll conveying mode, so that the continuous and large-scale preparation of the composite metal wire is realized. Compared with the single electrophoretic deposition of the nano-carbon, the nano-carbon and the metal in the nano-carbon metal film layer formed by composite electroplating are in a composite state, and at least part of nano-carbon is connected with the metal, so that the performances of heat conduction, electric conduction, strength and the like of the nano-carbon metal film are improved, and the deposition of the super-thick film layer can be realized. And the performance of the composite membrane in a two-dimensional plane and a one-dimensional tube direction can be adjusted by adjusting the proportion of graphene and carbon nanotubes in the nanocarbon.
Detailed Description
The following describes in detail the embodiments of the composite metal wire with composite electroplated nanocarbon metal film and the preparation method thereof provided by the invention with reference to the accompanying drawings.
Fig. 1 is a schematic flow chart illustrating a process of manufacturing a composite metal wire with a composite electroplated nanocarbon metal film according to an embodiment of the present invention.
In this embodiment, the process for preparing the composite metal wire with the composite electroplated nanocarbon metal film comprises the following steps:
step S101: a wire is provided.
The material of the metal wire comprises: various transition metal matrixes and alloys thereof with catalytic activity, such as metal simple substances of Cu, Ni, Ru, Co, Ta and the like and alloys thereof.
The metal wire is long, and the composite metal wire is continuously prepared in a large batch. In a specific embodiment of the present invention, the length of the metal wire is 1m or more, and may be 1 to 500m, and an appropriate length may be selected as needed. The diameter of the metal wire can be 10-500 mu m, and can be reasonably selected according to different use requirements.
Before the metal wire is treated, the metal wire can be annealed at the temperature of 600-1000 ℃ under H2And annealing in a protective atmosphere to eliminate the defects on the surface of the metal wire and remove impurities attached to the surface. The annealing treatment time can be 30-60 min.
Step S102: and dispersing the dispersed nano carbon powder and the metal salt in a solvent to prepare the composite electroplating solution.
In one embodiment of the present invention, the method for obtaining the nanocarbon powder comprises: and shearing and dispersing the nano carbon, carrying out acid washing treatment by adopting a mixed solution of concentrated nitric acid and concentrated hydrochloric acid, diluting the nano carbon into neutrality by using deionized water, and drying the nano carbon to obtain the dispersed nano carbon powder. Wherein, the volume ratio of the concentrated nitric acid and the concentrated hydrochloric acid can be 1:1, or other suitable ratios. In other embodiments, other methods, such as ball milling, dispersion, etc., may be used to obtain the dispersed nanocarbon powder.
The nanocarbon may comprise one or more combinations of single-walled carbon nanotubes, multi-walled carbon nanotubes, graphene, and derivatives thereof. The carbon nano tube has good performance along the direction of the tube, the graphene has good performance along a two-dimensional plane, and the proportion of the carbon nano tube and the graphene can be reasonably regulated and controlled according to specific use conditions and the requirements of the metal composite wires.
The metal in the metal salt comprises one or more of Cu, Ni, Ru, Co and Ta. The same or different material as the wire may be used.
And dispersing the nano carbon powder and the metal salt in a solvent according to a certain proportion to form the composite electroplating solution. The solvent may include at least one of an alcohol solution and a ketone solution, and specifically may include ethanol or acetone, and has good overall solubility for metal salts and nanocarbon, and is easy to volatilize, so that the metal wire is easy to dry after the composite plating. In some specific embodiments, a mixed solution of ethanol and acetone is used as a solvent, wherein the volume ratio of the ethanol to the acetone is 1: 9-9: 1.
In the composite electroplating solution, the metal salt with too high concentration easily corrodes the metal system and the container for holding the composite electroplating solution, and the too low concentration can lead to the low concentration of ions in the solution, so that the solution has poor conductivity and is not beneficial to the electrochemical deposition. In some embodiments of the present invention, the concentration of the nanocarbon powder is in a range of 0.1 to 0.9g/L, preferably, 0.3 to 0.6 g/L; the concentration range of the metal salt is 0.02-0.8 mol/L, preferably 0.3-0.6 mol/L. The ratio of nanocarbon in the nanocarbon metal film to be formed can be adjusted by adjusting the concentration of nanocarbon in the composite plating liquid.
Step S103: and continuously passing the metal wire through the composite electroplating solution in a roll-to-roll transmission mode, and simultaneously carrying out composite electroplating treatment on the surface of the metal wire to form a nano carbon metal film covering the surface of the metal wire. At least part of nano carbon is connected through metal in the formed nano carbon metal film, and the composite electroplating treatment comprises electrophoretic deposition and electroplating deposition which are carried out simultaneously. And drying the collected composite metal wire subjected to composite electroplating to obtain the composite metal wire with the composite electroplating nano metal carbon on the surface.
Through the roll-to-roll transmission mode, the continuous transmission of the metal wire can be realized, so that the continuous preparation of the composite metal wire is realized, and through controlling the roll-to-roll transmission rate, the time for carrying out composite electroplating on the surface of the metal wire can be controlled, so that the thickness of the formed composite film is controlled.
In the composite electroplating treatment process, the metal wire is connected to a cathode, and an anode is arranged in the composite electroplating solution. The anode may be a metal plate, the metal plate being of the same kind as the metal cations in the solution, the metal plate providing primarily the function of a conductive electrode and cations. Specifically, the anode metal plate may be made of one or a combination of Cu, Ni, Ru, Co, and Ta.
In the composite electroplating process, the metal wire is used as a cathode, and voltage is applied between the cathode and an anode to form an electric field. The metal plate provides positive ions to perform electroplating deposition of metal on the surface of the metal wire, and the nano carbon in the composite electroplating solution is subjected to electrophoresis under the action of an electric field until the nano carbon on the surface of the metal wire is subjected to electrophoresis. In the whole composite electroplating process, metal and nano carbon are simultaneously deposited to form a nano carbon metal film, and in the nano carbon metal film, the nano carbon and the metal are in a composite state, namely, the nano carbon is connected together through the metal, and chemical bonds are formed between carbon atoms and metal atoms, so that the problem that the strength is small due to the fact that the nano carbon is completely combined together through van der Waals force is solved, and the density, the strength and the heat conduction performance of the composite film can be improved. And metal bonds can be formed between the metal in the nano carbon metal film and atoms on the surface of the metal wire, so that the nano carbon metal film and the metal wire have high strength, and the nano carbon metal film and the metal wire are well combined at an interface, thereby being beneficial to improving the performances of heat conduction, electric conduction, strength and the like of the metal composite wire.
Referring to fig. 2, it is an electron microscope photograph of a carbon nanotube-copper composite film formed by composite electroplating; fig. 3 shows an electron microscope photograph of a graphene-copper composite film formed by composite plating.
The thickness of the nano carbon film can be reasonably controlled by regulating the content of nano carbon in the composite electroplating solution and the composite electroplating parameters, and the thickness of the metal coating can be controlled by controlling the concentration of the metal salt solution and the electroplating time; the overall thickness of the finally formed nanocarbon metal film can be adjusted by comprehensively controlling the content of nanocarbon in the composite electroplating solution, composite electroplating parameters, metal salt concentration and electroplating time. The nano carbon metal film has high compactness and strength, so that the deposition of an ultra-thick high-performance film layer can be realized, and the thickness of the film layer can be adjusted in a larger range by a person skilled in the art according to the requirement so as to meet the requirement of more application scenes.
According to the forming method of the composite metal wire, the metal wire is subjected to composite electroplating to form a nano carbon metal film on the surface of the metal wire in the process of conveying the metal wire in a roll-to-roll conveying mode, so that continuous and large-scale preparation of the composite metal wire is realized. Compared with the single electrophoretic deposition of the nano-carbon, the nano-carbon and the metal in the nano-carbon metal film layer formed by composite electroplating are in a composite state, and at least part of nano-carbon is connected with the nano-carbon through the metal, so that the heat conduction performance, the electric conduction performance, the strength performance and the like of the composite film are improved. And the performance of the composite membrane in a two-dimensional plane and a one-dimensional tube direction can be adjusted by adjusting the proportion of graphene and carbon nanotubes in the nanocarbon.
In another embodiment of the present invention, the metal wire includes a metal wire substrate and a graphene layer deposited on a surface of the metal wire substrate. Because the graphene and the nano carbon layer are homogeneous carbon interfaces, the surface of the graphene layer is subjected to composite plating, the chemical compatibility in the composite plating process is favorably improved, the interface bonding strength between the nano carbon metal film formed by the composite plating and the metal wire is increased, and meanwhile, the metal wire coated with the graphene is favorable for improving the corrosion resistance of the metal wire in the composite plating solution, so that the metal wire is prevented from being damaged by the composite plating solution.
The graphene layer may be formed using a chemical vapor deposition process, a plasma enhanced chemical vapor deposition process, or the like
In one embodiment, the method of forming the graphene layer includes: and transmitting the metal wire substrate between a roll-to-roll input end and a roll-to-roll output end by using a roll-to-roll deposition mode, and depositing the graphene layer on the surface of the metal wire substrate by using a Plasma Enhanced Chemical Vapor Deposition (PECVD) process in the transmission process of the metal wire substrate.
Generally, the smaller the diameter of the wire, the easier it is to form a higher quality graphene layer. However, due to the roll-to-roll transmission, the thin metal wires are easy to break during the transmission process, and the continuous preparation cannot be completed. In order to solve the above problems, the inventors carefully studied the deposition process of PECVD, and adjusted the deposition parameters of PECVD for the specific deposition substrate of wire, so that it has high coverage efficiency without the diameter of wire being too small. And in the roll-to-roll transmission process, the stress condition of the metal wire is comprehensively considered, the metal wire with the diameter of 10-500 mu m is selected as a deposition substrate, the deposition temperature of the plasma enhanced chemical vapor deposition process is controlled to be 700-850 ℃, the radio frequency power is controlled to be 5-200W, the adopted deposition gas comprises C, H element-containing gas, the flow rate of the deposition gas is 1-50 sccm, and the growth time of the graphene layer is 30-60 min.
In order to enable the graphene layer to have high deposition quality, the number of the graphene layers in the graphene layer is controlled to be 1-10. Due to the lower deposition temperature of PECVD, the metal wire substrate 201 may be selected from metals with lower melting points, thereby widening the range of materials selected for the metal wire substrate. The diameter of the metal wire substrate is 10-500 mu m, which is beneficial to PECVD deposition of graphene layers. The radio frequency power can be changed from 5W to 200W, and the deposition pressure is gradually increased, so that the controllable growth of the Gr layer number from 1 layer to 10 layers is realized, the adjustment of the graphene deposition layer number can be realized without adjusting the transmission speed of the metal wire, and the problems of breakage of the metal wire in the transmission process and the like are avoided.
By setting and adjusting the radio frequency power and the gas flow in the growth process of the graphene, the accurate layer number, quality and coverage rate of the graphene from a single layer to about ten layers on the surface of the metal wire can be realizedControlling to realize that the interfacial separation work between the graphene layer and the metal wire substrate is at least 0.72J/m2So as to meet the requirement of forming high-quality nano carbon metal film subsequently.
In a specific embodiment of the present invention, a copper wire is used as a metal wire substrate, and a composite metal wire with a nanocarbon metal film on the surface is specifically described as follows:
(1) annealing treatment of the metal wire substrate: the diameter of the metal wire is 10-500 μm, the length is 1-500m, the temperature is 600-1000 ℃, and the hydrogen content is 20-500sccm H2Annealing treatment is carried out under the condition.
(2) The method comprises the steps of utilizing a PECVD enhanced roll-to-roll (R2R) CVD process to deposit a certain number of layers of graphene (Gr) on the surface of a metal wire substrate at a low temperature, and adjusting the gas flow in a tube furnace to be 40-200 sccm Ar and 1-50 sccm CH4Changing the radio frequency power from 10W to 200W, and controlling the pressure within the range of 1-300 Torr, thereby realizing the controllable growth of Gr layers from a single layer to about ten layers on the metal wire substrate.
(3) Pretreatment of nano carbon: and (3) shearing and dispersing the nano-carbon, carrying out acid washing treatment for 2-5 h by adopting a mixed solution of concentrated nitric acid and concentrated hydrochloric acid in a volume ratio of 1:1, then diluting the nano-carbon into neutrality by using deionized water, and drying to obtain the pretreated nano-carbon.
(4) Preparation of composite plating solution: mixing the components in a volume ratio of 1:1, preparing a mixed solution from ethanol and acetone, taking 1L of the mixed solution, adding 0.2-0.4 g of pretreated nano carbon powder and 0.02-0.8 mol/L of metal salt, and performing ultrasonic dispersion for 5-8 hours to obtain the stable composite electroplating solution.
(5) Composite electroplating: in the schematic diagram of the composite plating process shown in fig. 4, one end of a wire 400 is wound around an output reel 401, and a conductive electrode (cathode) is contacted and then immersed in a composite plating solution 404, and the other end of the wire 400 is fixed on a collection reel 402, and the wire is transferred from the output reel 401 to the collection reel 402 by the rotation of the collection reel 402 and the output reel 401. A metal plate 406 is placed in the plating tank 403 containing the composite plating solution 404, and the metal plate 406 is connected to the positive electrode of the power source 407 to serve as an anode. A buffer scroll 405 is also arranged in the plating bath 403 and is used for entering the composite plating solutionThe wire in 404 is wound under the buffer reel, by which the position of the wire is defined. When the composite electroplating is carried out, the distance between the metal wire 400 and the metal plate 406 is 4-20 cm, the applied voltage is 20-40V/cm, and the current density is 0.4-8A/cm2The linear speed of the reel for transmitting the metal wire is 0.05-0.5 m/s. While the metal wire is continuously conveyed, a nano carbon metal film is formed on the surface.
(6) And (3) vacuum drying: and (3) drying the metal wire coated with the nano carbon metal film layer in a vacuum drying oven at room temperature.
The specific embodiment of the invention also provides the composite metal wire with the nano carbon metal film layer.
The composite metal wire includes: a metal wire; the nano carbon metal film covers the surface of the metal wire, at least part of nano carbon in the nano carbon metal film is connected through metal, and the nano carbon can be prevented from being completely combined together through Van der Waals force, so that the density and the strength of the nano carbon metal film can be improved, the nano carbon metal film has good cross section combination with the surface of the metal wire, and the heat conduction performance, the electric conduction performance, the strength performance and other performances of the composite film can be improved.
The material of the metal wire comprises: various transition metal matrixes and alloys thereof with catalytic activity, such as metal simple substances of Cu, Ni, Ru, Co, Ta and the like and alloys thereof.
Further, the metal wire comprises a metal wire substrate and a graphene layer deposited on the surface of the metal wire substrate.
Further, the graphene layer is a plasma enhanced chemical vapor deposition layer. The length of the metal wire base material is more than 1m, and the diameter of the metal wire base material is 10-500 mu m; the graphene layer comprises 1-10 layers of graphene, has a complete intrinsic structure and has good bonding strength with the metal wire substrate interface. The interfacial work of separation between the graphene layer and the metal wire substrate is at least 0.72J/m2. Because the graphene layer and the metal wire substrate have high bonding strength and good quality, and a homogeneous carbon interface is formed between the graphene layer and the metal wire substrate, the junction between the nano carbon metal film and the metal wire can be improvedThe resultant strength, and the quality of the nanocarbon metal film.
The nano carbon in the nano carbon metal film comprises one or more of single-walled carbon nanotubes, multi-walled carbon nanotubes, graphene and derivative products thereof. The metal in the nano carbon metal film comprises one or more of Cu, Ni, Ru, Co and Ta.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.