Method for depositing a graphene layer on a metal substrate surface, metal graphene composite conductor and use thereof

Abstract

The application relates to a method for depositing a graphene layer on a metal substrate surface, a metal graphene composite conductor and application thereof, and the method comprises the following steps: S1, preparing a first mixed layer on the metal substrate surface, and preparing a second mixed layer on the surface of the first mixed layer, the metal substrate comprises a first metal, the first mixed layer and the second mixed layer both comprise the first metal and an oxide of the first metal, and the content of the first metal oxide in the second mixed layer is higher than that in the first mixed layer; S2, heating the metal substrate and introducing a carbon-containing gas to reduce the oxide of the first metal and deposit a graphene layer in gas phase. Through cooperation of the first mixed layer and the second mixed layer with different copper oxide contents, the oxygen release rate is adjusted to be relatively uniform, the oxygen release time is prolonged, the oxygen release accompanies the whole gas phase deposition process, and the metal surface is better improved in the gas phase deposition process, so that a graphene layer with a large lattice and good orientation is formed.

Description

Technical Field

[0001] This application relates to the field of graphene composite material preparation technology, specifically to a method for depositing a graphene layer on the surface of a metal matrix, a metal-graphene composite conductor, and its applications. Background Technology

[0002] Graphene possesses advantages such as high electrical and thermal conductivity, high strength, high flexibility, strong chemical inertness, and excellent gas barrier properties. It is often used in combination with metals to create composite conductor materials, thereby improving the conductivity and mechanical properties of conductors. However, graphene itself is prone to aggregation and has poor wettability with metals, making graphene-metal composites technically challenging. Currently, the preferred method is vapor deposition of graphene, for example, depositing graphene on the surface of a copper substrate. However, due to the numerous active sites on the copper surface, graphene formed by vapor deposition often suffers from small grain size and poor lattice orientation, negatively impacting the resulting composite material and making it difficult to achieve the desired conductivity. Therefore, improving the conductivity of graphene composite materials is one of the important research directions in this field. Summary of the Invention

[0003] This application aims to provide a method for depositing a graphene layer on a metal substrate surface, a metal-graphene composite conductor, and its application, in order to solve the problem of reduced conductivity caused by small grain size and poor lattice orientation of graphene in the prior art.

[0004] The embodiments of this application are implemented as follows:

[0005] In a first aspect, embodiments of this application provide a method for depositing a graphene layer on the surface of a metal substrate, comprising:

[0006] S1, a first mixed layer is prepared on the surface of a metal substrate, and a second mixed layer is prepared on the surface of the first mixed layer. The metal substrate includes a first metal, and both the first mixed layer and the second mixed layer include the first metal and an oxide of the first metal. The content of the first metal oxide in the second mixed layer is higher than the content of the first metal oxide in the first mixed layer.

[0007] S2, the metal substrate is heated and a carbon-containing gas is introduced to reduce the oxide of the first metal and deposit a graphene layer in the vapor phase.

[0008] In one embodiment of this application, the method includes at least one of the following features:

[0009] (1) The mass content of the first metal oxide in the first mixed layer is 0.01-1.5%;

[0010] (2) The mass content of the first metal oxide in the second mixed layer is 0.05-3.0%;

[0011] (3) The thickness of the first mixing layer is greater than that of the second mixing layer;

[0012] (4) The thickness of the first hybrid layer is 0.3-0.95 μm;

[0013] (5) The thickness of the second hybrid layer is 0.1-0.5 μm.

[0014] In one embodiment of this application, S1 includes:

[0015] S1.1, Prepare a first plating solution, the first plating solution comprising a first metal oxide and a first metal ion;

[0016] S1.2, The metal substrate is placed in the first plating solution, and the first mixed layer is formed on the surface of the metal substrate by electroplating.

[0017] In one embodiment of this application, the first plating solution includes at least one of the following features:

[0018] (1) Copper oxide 0.5-1.8 g / L;

[0019] (2) Cuprous cyanide 50-65 g / L;

[0020] (3) Potassium cyanide 100-135 g / L;

[0021] (4) Potassium hydroxide 11-16 g / L;

[0022] (5) Potassium thiocyanate content: 12-18 g / L;

[0023] (6) Potassium sodium tartrate 17-28 g / L;

[0024] (7) Dispersant 20-35g / L 。

[0025] In one embodiment of this application, in step S1.2, the electroplating current density is 0.2-0.5 A / dm2;

[0026] And / or, the temperature of the first plating solution is 16-24°C;

[0027] And / or, the pH value of the first plating solution is 7.5-10.5.

[0028] In one embodiment of this application, S1 includes:

[0029] S1.3, Prepare a second plating solution, the second plating solution comprising a first metal oxide and a first metal ion;

[0030] S1.4, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer is formed by electroplating on the surface of the first mixed layer.

[0031] In one embodiment of this application, the second plating solution includes at least one of the following features:

[0032] (1) Copper oxide 1.0-3.0 g / L;

[0033] (2) Cuprous cyanide 50-65 g / L;

[0034] (3) Potassium cyanide 100-135 g / L;

[0035] (4) Potassium hydroxide 11-16 g / L;

[0036] (5) Potassium thiocyanate content: 12-18 g / L;

[0037] (6) Potassium sodium tartrate 17-28 g / L;

[0038] (7) Dispersant 20-35g / L.

[0039] In one embodiment of this application, in step S1.4, the electroplating current density is 0.3-0.7 A / dm2;

[0040] And / or, the temperature of the second plating solution is 16-24°C;

[0041] And / or, the pH value of the second plating solution is 7.5-10.5.

[0042] In one embodiment of this application, in step S2, the metal substrate is heated to 850-1050°C at a heating rate of 10-20°C / min.

[0043] In one embodiment of this application, in step S2, the carbon-containing gas includes methane, and the amount of methane introduced is 15-100 sccm.

[0044] In one embodiment of this application, in step S2, the temperature is increased and a carbon-containing gas is introduced into an inert gas atmosphere, the inert gas including nitrogen and / or argon, and the amount of inert gas introduced is 0-1000 sccm.

[0045] In one embodiment of this application, in step S2, hydrogen gas is introduced simultaneously with the carbon-containing gas, and the amount of hydrogen gas introduced is 5-500 sccm.

[0046] In one embodiment of this application, in step S2, a pre-pyrolysis chamber is provided before the vapor deposition chamber, and an oxide-formed plate or particulate carrier is provided in the pre-pyrolysis chamber so that the carbon-containing gas passes through the pre-pyrolysis chamber and then enters the vapor deposition chamber.

[0047] In one embodiment of this application, the temperature of the pre-pyrolysis chamber is increased so that the temperature of the pre-pyrolysis chamber is the same as the temperature of the vapor deposition chamber.

[0048] Secondly, embodiments of this application also provide a metal-graphene composite conductor, which is manufactured using the method described in any one of the first aspects, wherein the metal-graphene composite conductor comprises:

[0049] Metallic matrix, including a first metal;

[0050] A metal-graphene composite layer is disposed on at least one surface of the metal substrate;

[0051] The metal-graphene composite layer includes a first porous metal layer, a second porous metal layer, and a graphene layer. Both the first porous metal layer and the second porous metal layer include the first metal. The first porous metal layer is located between the second porous metal layer and the metal substrate. The graphene layer covers the second porous metal layer and fills the pores in the first porous metal layer and the pores in the second porous metal layer.

[0052] The porosity of the second porous metal layer is greater than that of the first porous metal layer, and at least the inner wall of the pores and the surface of the adjacent inner wall of the pores are hydrophobic surfaces.

[0053] In one embodiment of this application, the first metal includes copper;

[0054] And / or, the porosity of the first porous metal layer is 1.5-5%;

[0055] And / or, the porosity of the second porous metal layer is 4-8%.

[0056] In one embodiment of this application, the first porous metal layer is configured to be formed by reducing a first mixed layer, and the second porous metal layer is configured to be formed by reducing a second mixed layer;

[0057] Both the first mixed layer and the second mixed layer are mixed electroplated layers of a first metal and a first metal oxide, and the content of the first metal oxide in the second mixed layer is higher than that in the first mixed layer.

[0058] Thirdly, embodiments of this application also provide an application of the metal-graphene composite conductor described in any of the second aspects as a wire, cable, or electrical contact.

[0059] Beneficial effects:

[0060] The technical solution provided in this application involves the reduction and decomposition of metal oxides at high temperatures during graphene vapor deposition to release oxygen. Carbon-containing gases are accelerated to decompose and generate free carbon under the promotion of oxygen, which is beneficial to the formation of graphene layers. At the same time, the presence of oxygen can passivate the surface of the metal substrate, reduce the metal activity of oxygen-containing regions, reduce the number of nucleation sites, and improve the grain size and lattice orientation of graphene. This solves the problem of reduced conductivity caused by small grain size and poor lattice orientation of graphene in the prior art, and also improves thermal conductivity.

[0061] A second mixed layer is prepared on the first mixed layer. The copper oxide content, density, and thickness of the first and second mixed layers are controlled so that the copper oxide content of the second mixed layer is higher than that of the first mixed layer, the density of the second mixed layer is lower than that of the first mixed layer, and the thickness of the second mixed layer is smaller than that of the first mixed layer. This is to adjust the oxygen release rate, make the oxygen release rate relatively uniform, and prolong the oxygen release time, so that oxygen release accompanies the entire vapor deposition process. This is beneficial to better improve the metal surface during the vapor deposition process and form a graphene layer with large lattice and good orientation. Attached Figure Description

[0062] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0063] Figure 1 A method for preparing a first hybrid layer and a second hybrid layer on the surface of a metal substrate is provided in one embodiment of this application;

[0064] Figure 2 A method for preparing a first hybrid layer on the surface of a metal substrate is provided in one embodiment of this application;

[0065] Figure 3 A method for preparing a second hybrid layer on the surface of a first hybrid layer is provided in one embodiment of this application. Detailed Implementation

[0066] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Furthermore, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application.

[0067] In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in its actual use or operating state, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device. Furthermore, in the description of this application, the term "comprising" means "including but not limited to". The terms first, second, third, etc., are used merely as illustrative purposes and do not impose numerical requirements or establish a numerical order.

[0068] In this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural.

[0069] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one," "at least one of the following," or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c," or "at least one of a, b, and c," can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0070] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.

[0071] Graphene itself is prone to aggregation and has poor wettability with metals, which makes the composite of graphene and metals technically challenging. Currently, the preferred method is to composite graphene by vapor deposition, such as vapor deposition of graphene on the surface of copper. However, due to the large number of active sites on the copper surface, the graphene formed by vapor deposition often has problems such as small grain size and poor lattice orientation, which has a negative impact on the resulting composite material and makes it difficult to achieve the expected conductivity.

[0072] In related technologies, to address the issues of small grain size and numerous defects in graphene, a pretreatment of the metal substrate surface is considered. This involves oxidizing the metal substrate surface and then reducing the oxidized metal to improve the surface structure of the metal substrate, thereby improving the formation of graphene grown on the metal substrate surface. However, while this method can alleviate the problems of the composite material to some extent, other issues remain. In some pretreatment methods for the metal substrate surface, direct oxidation of the metal substrate is used. This process requires precise control of the heating rate, ambient temperature and humidity, and the amount of oxidizing agent. The oxidation depth of the metal substrate is difficult to control, which can easily lead to incomplete reduction of the oxidized metal, thus adversely affecting the performance of the composite material.

[0073] Firstly, this application provides a method for depositing a graphene layer on a metal substrate. Firstly, a first mixed layer and a second mixed layer comprising the metal and its oxide are prepared on the surface of the metal substrate. Then, the metal substrate is heated to a certain temperature, and a carbon-containing gas is simultaneously introduced to deposit graphene in the vapor phase. During the graphene vapor deposition process, the metal oxides in the first and second mixed layers are reduced and decomposed at high temperature to generate metal and release oxygen. The carbon-containing gas, under the promoting effect of oxygen, decomposes rapidly to generate free carbon, which is beneficial to the formation of the graphene layer. Simultaneously, the presence of oxygen can passivate the surface of the metal substrate, reduce the metal activity in oxygen-containing regions, reduce the number of nucleation sites, and improve the grain size and lattice orientation of graphene, solving the problem of reduced conductivity due to small grain size and poor lattice orientation of graphene in the prior art. Furthermore, the reduction of the metal oxides produces metal, water, carbon dioxide, etc., without introducing new impurities into the metal substrate, and the water and carbon dioxide can be discharged with the carbon-containing gas. In addition, the reduction of copper oxide in the first and second mixed layers releases oxygen and creates voids, which can be used for graphene vapor deposition, allowing graphene to be uniformly mixed with the metal.

[0074] The first and second mixed layers have different metal oxide contents, with the first layer having a relatively low metal oxide content and the second layer having a relatively high metal oxide content. The second mixed layer, located on the surface, rapidly provides a large amount of oxygen in the early stages of vapor deposition to promote a rapid reaction. In the later stages of vapor deposition, the second mixed layer creates voids after releasing oxygen, allowing oxygen from the inner first mixed layer to be released through these voids, replenishing the consumed oxygen. Under the influence of the second mixed layer, oxygen release accompanies the entire vapor deposition process. Therefore, the technical solution of this application, by combining the first and second mixed layers, achieves control over both the metal oxide content and the oxygen release rate, ensuring complete reduction of the metal oxides while guaranteeing oxygen release that promotes the reaction throughout the entire vapor deposition process. Furthermore, the relatively low metal oxide content of the first mixed layer and the higher metal oxide content of the second mixed layer result in a denser inner structure, maintaining better mechanical and processing properties.

[0075] like Figure 1 As shown, the method for depositing a graphene layer on a metal substrate includes:

[0076] S1, a first mixed layer is prepared on the surface of a metal substrate, and a second mixed layer is prepared on the surface of the first mixed layer. The metal substrate includes a first metal, and both the first mixed layer and the second mixed layer include the first metal and an oxide of the first metal. The content of the first metal oxide in the second mixed layer is higher than that in the first mixed layer.

[0077] S2, the metal substrate is heated and a carbon-containing gas is introduced to reduce the oxide of the first metal and deposit a graphene layer in the vapor phase.

[0078] like Figure 2 As shown, the method of preparing the first hybrid layer on the surface of the metal substrate includes electroplating, i.e., S1 includes:

[0079] S1.1, Prepare a first plating solution, the first plating solution comprising a first metal ion and a first metal oxide;

[0080] S1.2, The metal substrate is placed in the first plating solution, and the first mixed layer is formed on the surface of the metal substrate by electroplating.

[0081] In this application, copper is selected as the first metal to illustrate the technical solution provided in this application in detail, but this is not to be regarded as a limitation of this solution. That is, the metal forming the metal matrix includes, but is not limited to, copper, and the mixed layer includes, but is not limited to, copper and copper oxide.

[0082] In some embodiments, the first plating solution includes copper oxide, cuprous cyanide, potassium cyanide, potassium hydroxide, potassium thiocyanate, potassium sodium tartrate, and a dispersant, wherein the copper oxide is 0.5-1.8 g / L, the cuprous cyanide is 50-65 g / L, the potassium cyanide is 100-135 g / L, the potassium hydroxide is 11-16 g / L, the potassium thiocyanate is 12-18 g / L, the potassium sodium tartrate is 17-28 g / L, and the dispersant is 20-35 g / L. The dispersant includes, but is not limited to, sodium dodecyl sulfate and hexadecyltrimethylammonium bromide.

[0083] Copper oxide provides the metal oxide for deposition, while cuprous cyanide, in the presence of components such as potassium cyanide, provides the metal ions for deposition. The concentration of copper oxide is 0.5-1.8 g / L, and cuprous cyanide is 50-65 g / L. For example, copper oxide concentrations of 0.5 g / L, 0.6 g / L, 0.7 g / L, 0.9 g / L, 1.0 g / L, 1.1 g / L, 1.3 g / L, 1.5 g / L, or 1.8 g / L, and cuprous cyanide concentrations of 50 g / L, 51 g / L, 53 g / L, 55 g / L, 56 g / L, 58 g / L, 60 g / L, 62 g / L, 64 g / L, or 65 g / L, are used. The ratio of copper oxide to cuprous cyanide ranges from approximately 0.015 to 0.06 to ensure the copper oxide content is within a suitable range, avoiding excessive copper oxide content which could lead to insufficient subsequent reduction and affect the performance of the composite material.

[0084] Potassium cyanide is used as a complexing agent. By adding potassium cyanide at a concentration of 100-135 g / L, such as 100 g / L, 105 g / L, 110 g / L, 112 g / L, 116 g / L, 119 g / L, 122 g / L, 124 g / L, 127 g / L, 128 g / L, 130 g / L, 132 g / L, or 135 g / L, the ratio of the main salt to potassium cyanide is 0.37-0.68. The amount of potassium cyanide added is greater than that of cuprous cyanide to ensure sufficient complexation of cuprous cyanide. The potassium cyanide not used for complexation exists in a free state in the plating solution. The free potassium cyanide can improve the stability of the copper-cyanide complex in the first plating solution, which is beneficial to the stable electroplating process.

[0085] Sodium potassium tartrate, as an anodic depolarizer, increases the complexation ability of the plating solution for copper, reduces the copper precipitation sites, and thus improves the dispersion ability of the plating solution.

[0086] A higher content of free potassium cyanide increases anodic current efficiency but decreases cathodic current efficiency. The free potassium cyanide content can be appropriately reduced by using potassium sodium tartrate. The addition amount of potassium sodium tartrate is 17-28 g / L, for example, 17 g / L, 19 g / L, 20 g / L, 24 g / L, 25 g / L, 27 g / L, or 28 g / L. The ratio of potassium cyanide to potassium sodium tartrate is approximately 3.5-8, which achieves a good balance between anodic and cathodic current efficiency.

[0087] Potassium hydroxide at concentrations of 11-16 g / L (e.g., 11 g / L, 12 g / L, 14 g / L, or 16 g / L) can improve the conductivity of the plating solution and result in finer crystals.

[0088] Potassium thiocyanate at concentrations of 12-18 g / L (e.g., 12 g / L, 14 g / L, 15 g / L, 16 g / L, or 18 g / L) can improve the conductivity of the plating solution, increase electroplating efficiency, and stabilize the coating.

[0089] In some embodiments, during electroplating, the first plating solution is prepared such that the pH value of the first plating solution when applied in S1.2 is 7.5-10.5, for example, pH values ​​of 7.5, 8, 8.5, 9, 9.5, 10 or 10.5.

[0090] In some embodiments, in S1.2, the temperature of the first plating solution is 16-24°C, for example, the temperature of the first plating solution is maintained at 16°C, 18°C, 19°C, 20°C, 22°C or 24°C.

[0091] In some embodiments, in S1.2, the electroplating current density is 0.2-0.5 A / dm². By controlling the electroplating current density, for example, controlling it to 0.2 A / dm², 0.3 A / dm², 0.4 A / dm², or 0.5 A / dm², the formation rate of the first mixed layer can be adjusted, thereby controlling the density of the first mixed layer. After the copper oxide in the first mixed layer is reduced and releases oxygen, voids will be generated. Adjusting the density of the first mixed layer can control the size and density of these voids. During subsequent vapor deposition, graphene is deposited not only on the surface of the first mixed layer but also in the voids. By adjusting the void distribution of the first mixed layer, the graphene and copper can be bonded more uniformly and effectively.

[0092] In some embodiments, after step S1.2, the first mixed layer completely covers the metal substrate, so that the metal oxides in the first mixed layer are uniformly distributed on the surface of the metal substrate, and the oxygen-containing regions are more uniformly distributed, which is beneficial to improving the uniformity of graphene.

[0093] In some embodiments, the mass content of the metal oxide in the first mixed layer is 0.01-1.5%.

[0094] In some embodiments, the metal oxide content of the second mixed layer is 0.05-3.0% by mass.

[0095] By controlling the copper oxide content of the first and second mixed layers, while ensuring oxygen release throughout the entire vapor deposition process, the copper oxide is fully reduced, thus avoiding residual copper oxide from affecting the performance of the composite material.

[0096] Furthermore, the thickness of the first mixing layer is set to be greater than that of the second mixing layer to further prolong the time for oxygen release from the first mixing layer, thereby ensuring that oxygen release accompanies the entire vapor deposition process as much as possible.

[0097] Optionally, the thickness of the first mixing layer is 0.1-0.5 μm.

[0098] Optionally, the thickness of the second mixing layer is 0.3-0.95 μm.

[0099] After the first mixed layer is prepared in S1, the second mixed layer is prepared. There are various methods for preparing the second mixed layer, such as oxidizing the surface of the first mixed layer to obtain a second mixed layer with a higher copper oxide content. In this application, the second mixed layer is prepared by electroplating to better control the copper oxide content. Figure 3 As shown, S1 also includes:

[0100] S1.3, prepare a second plating solution, the second plating solution including a first metal ion and a first metal oxide, wherein the concentration of the first metal oxide in the second plating solution is greater than the concentration of the first metal oxide in the first plating solution;

[0101] S1.4, The metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer is formed by electroplating on the surface of the first mixed layer.

[0102] For example, the second plating solution includes copper oxide, cuprous cyanide, potassium cyanide, potassium hydroxide, potassium thiocyanate, potassium sodium tartrate, and a dispersant, wherein the dispersant includes, but is not limited to, sodium dodecyl sulfate and hexadecyltrimethylammonium bromide. In the second plating solution, the concentrations are as follows: copper oxide 1.0-3.0 g / L, cuprous cyanide 50-65 g / L, potassium cyanide 100-135 g / L, potassium hydroxide 11-16 g / L, potassium thiocyanate 12-18 g / L, potassium sodium tartrate 17-28 g / L, and dispersant 20-35 g / L. Compared to the first plating solution, the concentration of copper oxide in the second plating solution is higher than that in the first plating solution, which is beneficial for forming a second mixed layer with a relatively high copper oxide content. This allows the second mixed layer to provide sufficient oxygen in the early stages of graphene vapor deposition and subsequently provide sufficient porosity for oxygen release from the first mixed layer.

[0103] In some embodiments, during electroplating, a second plating solution is prepared such that the pH value of the second plating solution when applied in S1.4 is 7.5-10.5.

[0104] In some embodiments, in S1.4, the temperature of the first plating solution is 16-24°C.

[0105] In some embodiments, in S1.4, the electroplating current density is 0.3-0.7 A / dm2. The second electroplating current density is greater than the first electroplating current density, which makes the formation rate of the first mixed layer slower and the formation rate of the second mixed layer faster. The first mixed layer is denser than the second mixed layer, thereby providing sufficient oxygen in the early stage and having sufficient pores for oxygen release in the later stage, thus balancing the full reduction of copper oxide and oxygen release.

[0106] In some embodiments, in S2, the metal substrate is heated to 850-1050°C at a heating rate of 10-20°C / min to rapidly increase the temperature of the metal substrate, thereby causing the metal oxide to decompose at a high temperature, for example, completing the transformation from copper oxide to cuprous oxide and then to copper.

[0107] After heating to the set temperature, a carbon-containing gas, including methane, is introduced at a rate of 15-100 sccm. By controlling the density and copper oxide content of the first and second mixing layers, the release amount and rate of oxygen are controlled. This, combined with controlling the methane introduction rate, promotes the decomposition of methane under the action of oxygen to generate sufficient free carbon, thereby improving the graphene deposition efficiency: CH4+O→CH3, CH3+O→CH2, CH2+O→CH, CH+O→C.

[0108] In some embodiments, a pre-pyrolysis chamber is provided before the vapor deposition chamber, so that carbon-containing gas passes through the pre-pyrolysis chamber before entering the vapor deposition chamber. An oxide-formed plate or particulate carrier is provided in the pre-pyrolysis chamber to promote the early release of hydrogen atoms from some of the carbon-containing gas and the formation of free carbon, so that the carbon-containing gas decomposes more completely and there is more free carbon in the vapor deposition chamber, which is conducive to the good, uniform and rapid formation of graphene layers.

[0109] Optionally, the temperature of the pre-pyrolysis chamber is the same as that of the vapor deposition chamber, so that the carbon-containing gas is heated in the pre-pyrolysis chamber and the entry of carbon-containing gas causes temperature fluctuations in the vapor deposition chamber.

[0110] In S2, an inert gas is first introduced, and the metal substrate is heated in the inert gas atmosphere while a carbon-containing gas is introduced. Under the protection of the inert gas, the metal is prevented from being oxidized by the air. The inert gas includes nitrogen and / or argon, and the amount of inert gas introduced is 0-1000 sccm.

[0111] In S2, hydrogen gas is introduced simultaneously with carbon-containing gas, at a rate of 5-500 sccm, to promote graphene growth.

[0112] Secondly, embodiments of this application also provide a metal-graphene composite conductor, which is manufactured using any of the methods in the first aspect. The metal-graphene composite conductor includes a metal substrate and a metal-graphene composite layer disposed on at least one surface of the metal substrate.

[0113] The metal-graphene composite layer includes a first porous metal layer, a second porous metal layer, and a graphene layer. Both the first and second porous metal layers include a first metal. The first porous metal layer is located between the second porous metal layer and the metal substrate. The graphene layer covers the second porous metal layer and fills the pores in the first and second porous metal layers.

[0114] The porosity of the second porous metal layer is greater than that of the first porous metal layer. At least the inner walls of the pores and the surfaces of adjacent pores are hydrophobic surfaces. These hydrophobic surfaces are passivated metal surfaces after oxidation-reduction processes, such as the surface of reduced copper oxide or the surface of copper after contact with oxygen release.

[0115] The first porous metal layer is constructed by reducing the aforementioned first mixed layer. That is, the first metal oxide (such as copper oxide) in the first mixed layer is reduced and releases oxygen during the vapor deposition of graphene, which promotes the accelerated deposition of graphene and passivates the metal surface to facilitate the further formation of a hydrophobic surface, thereby reducing the number of nucleation sites and improving the grain size of graphene.

[0116] Similarly, the second porous metal layer is constructed to be formed by the reduction of the aforementioned second mixed layer. That is, the first metal oxide (such as copper oxide) in the second mixed layer is reduced and releases oxygen during the vapor deposition of graphene, which promotes the accelerated deposition of graphene, passivates the metal surface to facilitate the further formation of a hydrophobic surface, thereby reducing the number of nucleation sites and improving the grain size of graphene.

[0117] During the reduction and release of oxygen, the closer the position is to the first metal oxide, the easier it is to come into contact with oxygen and form a hydrophobic surface. Therefore, among the surfaces of the first porous metal layer and the second porous metal layer, at least the inner walls of the pores and the surfaces of the adjacent inner walls of the pores are hydrophobic surfaces.

[0118] The graphene layer is mainly deposited on the surface of the second mixed layer. By making the content of the first metal oxide in the second mixed layer higher than that in the first mixed layer, the surface of the second mixed layer is more likely to form a hydrophobic surface, which can better improve the grain size of graphene.

[0119] Meanwhile, the relatively high porosity of the second mixed layer facilitates the release of oxygen from the first mixed layer, promoting the subsequent decomposition of carbon-containing gases. Conversely, the relatively low porosity of the first mixed layer and its higher content of the first metal contribute to improved bonding stability between the metal-graphene composite layer and the metal matrix.

[0120] In some embodiments, the porosity of the first porous metal layer is 1.5-5%.

[0121] In some embodiments, the porosity of the second porous metal layer is 4-8%.

[0122] Thirdly, embodiments of this application also provide an application of any of the metal-graphene composite conductors in the second aspect as wires, cables, or electrical contacts.

[0123] The present application will be specifically described below through specific embodiments. These embodiments are only some embodiments of the present application and are not intended to limit the present application. Unless otherwise specified, the raw materials used in the following embodiments are all commercially available products.

[0124] Example 1

[0125] S1, Preparation of the hybrid layer

[0126] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0127] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm². 2 The temperature of the first plating solution is 20℃.

[0128] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0129] S1.2, the metal substrate having the first hybrid layer is placed in the second plating solution, and a second hybrid layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm². 2 The temperature of the second plating solution is 20℃.

[0130] S2, vapor-deposited graphene

[0131] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0132] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0133] Example 2

[0134] S1, Preparation of the hybrid layer

[0135] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0136] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0137] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0138] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.2 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0139] S2, vapor-deposited graphene

[0140] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0141] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0142] Example 3

[0143] S1, Preparation of the hybrid layer

[0144] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0145] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0146] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0147] S1.2, The metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.4 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0148] S2, vapor-deposited graphene

[0149] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0150] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0151] Example 4

[0152] S1, Preparation of the hybrid layer

[0153] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0154] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.9 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0155] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0156] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0157] S2, vapor-deposited graphene

[0158] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0159] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0160] Example 5

[0161] S1, Preparation of the hybrid layer

[0162] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0163] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.5 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2, and the temperature of the first plating solution is 20℃.

[0164] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0165] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0166] S2, vapor-deposited graphene

[0167] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0168] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0169] Example 6

[0170] S1, Preparation of the hybrid layer

[0171] S1.1, Prepare the first plating solution, which includes 1.5 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0172] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0173] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0174] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0175] S2, vapor-deposited graphene

[0176] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0177] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0178] Example 7

[0179] S1, Preparation of the hybrid layer

[0180] S1.1, Prepare the first plating solution, which includes 0.6 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0181] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0182] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0183] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0184] S2, vapor-deposited graphene

[0185] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0186] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0187] Example 8

[0188] S1, Preparation of the hybrid layer

[0189] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0190] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0191] S1.3, Prepare the second plating solution, which includes 2.5 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0192] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0193] S2, vapor-deposited graphene

[0194] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0195] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0196] Example 9

[0197] S1, Preparation of the hybrid layer

[0198] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0199] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0200] S1.3, Prepare the second plating solution, which includes 1.5 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0201] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0202] S2, vapor-deposited graphene

[0203] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0204] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0205] Example 10

[0206] S1, Preparation of the hybrid layer

[0207] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0208] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0209] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0210] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.7 A / dm2 and the temperature of the second plating solution is 20℃.

[0211] S2, vapor-deposited graphene

[0212] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0213] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0214] Example 11

[0215] S1, Preparation of the hybrid layer

[0216] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0217] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0218] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0219] S1.2, The metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.4 A / dm2 and the temperature of the second plating solution is 20℃.

[0220] S2, vapor-deposited graphene

[0221] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0222] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0223] Example 12

[0224] S1, Preparation of the hybrid layer

[0225] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0226] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.4 A / dm2 and the temperature of the first plating solution is 20℃.

[0227] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0228] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0229] S2, vapor-deposited graphene

[0230] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0231] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0232] Example 13

[0233] S1, Preparation of the hybrid layer

[0234] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0235] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.2 A / dm2, and the temperature of the first plating solution is 20℃.

[0236] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0237] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0238] S2, vapor-deposited graphene

[0239] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0240] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0241] Example 14

[0242] S1, Preparation of the hybrid layer

[0243] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0244] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0245] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0246] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0247] S2, vapor-deposited graphene

[0248] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0249] S2.2, carbon-containing gas (methane) is introduced into the pre-pyrolysis chamber and then into the gas phase deposition chamber. Hydrogen is introduced into the gas phase deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0250] Example 15

[0251] S1, Preparation of the hybrid layer

[0252] S1.1, Prepare the first plating solution, which includes 6 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0253] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0254] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0255] S1.2, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 0.3 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0256] S2, vapor-deposited graphene

[0257] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0258] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0259] Example 16

[0260] S1, Preparation of the hybrid layer

[0261] S1.1, Prepare the first plating solution, which includes 1.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the first plating solution is 8.0.

[0262] S1.2, The metal substrate (copper substrate) is placed in the first plating solution, and a first mixed layer with a thickness of 0.8 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.3 A / dm2 and the temperature of the first plating solution is 20℃.

[0263] S1.3, Prepare the second plating solution, which includes 2.0 g / L copper oxide, 60 g / L cuprous cyanide, 130 g / L potassium cyanide, 15 g / L potassium hydroxide, 13 g / L potassium thiocyanate, 18 g / L sodium potassium tartrate, and 22 g / L dispersant. The pH value of the second plating solution is 8.0.

[0264] S1.2, The metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer with a thickness of 1.0 μm is formed on the surface of the metal substrate by electroplating, wherein the electroplating current density is 0.6 A / dm2 and the temperature of the second plating solution is 20℃.

[0265] S2, vapor-deposited graphene

[0266] S2.1, Place the metal substrate in the vapor deposition chamber, introduce argon gas at a rate of 800 sccm, and heat the metal substrate to 1000℃ in the argon atmosphere at a rate of 15℃ / min.

[0267] S2.2, a carbon-containing gas (methane) is introduced into the vapor deposition chamber, and hydrogen is introduced into the vapor deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0268] Comparative Example 1

[0269] (1) Place the copper substrate in the vapor deposition chamber and introduce argon gas at a rate of 800 sccm. In the argon atmosphere, heat the metal substrate to 1000℃ at a rate of 15℃ / min.

[0270] (2) Carbon-containing gas methane is introduced into the pre-cracking chamber and then into the gas phase deposition chamber. Hydrogen is introduced into the gas phase deposition chamber, wherein the amount of carbon-containing gas introduced is 100 sccm and the amount of hydrogen introduced is 150 sccm.

[0271] Comparative Example 2

[0272] (1) Electroplating to form a copper oxide layer on a copper substrate.

[0273] (2) Heat to 800℃ to reduce copper oxide and form a hydrophobic copper layer on the surface of the copper substrate.

[0274] (3) Graphene was vapor-deposited on the surface of the hydrophobic copper layer at 1000℃.

[0275] Comparative Example 3

[0276] (1) Weigh 200g of 100-mesh copper powder, place it in a ceramic boat, and spread it evenly. The copper powder can be any of the following: spherical, dendritic, or flake-shaped. Push the ceramic boat containing the copper powder to the center of the constant temperature zone of the chemical vapor deposition furnace, introduce 300 sccm of argon gas, so that the copper powder is in an argon atmosphere, and raise the furnace temperature from room temperature to 300℃ in the argon atmosphere. Turn off the argon gas and introduce 1 sccm of oxygen to pre-oxidize the surface of the copper powder and keep it at that temperature for 10 minutes.

[0277] (2) After holding the temperature for 10 minutes, the oxygen was turned off and the argon gas flow was restored to 300 sccm. The furnace temperature was continuously raised to 1050°C in the argon atmosphere. Then, a mixture of methane, hydrogen and argon was introduced into the furnace, with a flow rate of 50 sccm for methane, 200 sccm for hydrogen and 300 sccm for argon. In the atmosphere of this mixed gas, the surface of the copper powder was reduced, and at the same time, a graphene film began to grow on the surface of the copper powder. The growth time was 30 minutes, and the growth product was obtained.

[0278] (3) After the growth is completed, methane and hydrogen are turned off, and the growth product is cooled naturally in an argon atmosphere formed by 300 sccm of argon to form a sample.

[0279] The copper-graphene composite conductors prepared in Examples 1-16 and Comparative Examples 1, 2, and 3 were respectively made into wires of the same specifications, and copper wires of the same specifications were prepared using copper material. The electrical conductivity and thermal conductivity of each wire were measured, and the test results are shown in Table 1.

[0280]

[0281] As shown in Table 1, the copper-graphene composite conductors provided in Examples 1-16, Comparative Examples 1, 2, and 3 all exhibit better electrical and thermal conductivity compared to the basic copper wires. However, Examples 1-16 show even higher electrical and thermal conductivity compared to Comparative Example 1, indicating that the method provided in this application can further improve the grain size and lattice defects of copper-graphene, thereby enhancing the electrical and thermal conductivity of the graphene composite conductors. In addition, Examples 1-16 all exhibit higher electrical and thermal conductivity compared to Comparative Examples 2 and 3, indicating that the prepared graphene composite conductors have better electrical and thermal conductivity. However, the method used in Comparative Example 2 requires three steps: electroplating, reduction, and vapor deposition. In this application, reduction and vapor deposition are carried out simultaneously, enabling the reuse of oxygen generated during reduction and promoting methane cracking. Furthermore, only one high-temperature step is required, which is environmentally friendly, energy-saving, and simplifies the process. In other words, this application has prepared a metal-graphene composite product with better electrical and thermal conductivity through a simpler process and a more environmentally friendly and energy-saving process. In contrast to Example 3, during the vapor deposition of graphene, the process involves heating the metal substrate, first introducing oxygen to pre-oxidize the surface of the metal substrate, and then turning off the oxygen and introducing carbon-containing gas for vapor deposition. While this method can improve the formation of graphene grown on the surface of the metal substrate to some extent, in actual operation, the oxidation depth of the metal substrate is difficult to control precisely, which can easily lead to incomplete reduction of the oxidized metal, thus adversely affecting the performance of the composite material. The solution proposed in this application, which sets up a first mixing layer and a second mixing layer, achieves better results.

[0282] Compared with Examples 2 and 3, Example 1 shows that the thickness of the second mixed layer can be adjusted within a certain range; compared with Examples 4 and 5, Example 1 shows that the thickness of the first mixed layer can be adjusted within a certain range; compared with Examples 6 and 7, Example 1 shows that adjusting the concentration of copper oxide in the first plating solution and thus the content of copper oxide in the first plating layer within a certain range still achieves good results; compared with Examples 8 and 9, Example 1 shows that adjusting the concentration of copper oxide in the second plating solution and thus the content of copper oxide in the second plating layer within a certain range still achieves good results; compared with Examples 10 and 11, Example 1 shows that adjusting the electroplating current within a certain range to control the density of the second plating layer still achieves good results; compared with Examples 12 and 13, Example 1 shows that adjusting the electroplating current within a certain range to control the density of the first plating layer still achieves good results; compared with Example 14, Example 1 shows that passing the carbon-containing gas through a pre-cracking chamber for catalysis and heating can further improve the electrical and thermal conductivity of the graphene composite conductor. Compared with Example 15, Example 1 shows that the copper oxide content achieves better results within the range specified in this application. Compared with Example 16, Example 1 shows that when the thickness of the second mixing layer is smaller than that of the first mixing layer, the effect is better.

[0283] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for depositing a graphene layer on a metal substrate surface, characterized in that, include: S1, a first mixed layer is prepared on the surface of a metal substrate, and a second mixed layer is prepared on the surface of the first mixed layer. The metal substrate includes a first metal, and both the first mixed layer and the second mixed layer include the first metal and an oxide of the first metal. The content of the first metal oxide in the second mixed layer is higher than the content of the first metal oxide in the first mixed layer. S2, the metal substrate is heated and a carbon-containing gas is introduced to reduce the oxide of the first metal and deposit a graphene layer in the vapor phase. The first metal oxide in the first mixed layer and the second mixed layer is reduced and decomposed to generate the first metal and release oxygen. After the oxygen is released, voids are generated in the first mixed layer and the second mixed layer. Wherein, the first metal includes copper, and the oxide of the first metal includes copper oxide.

2. The method for depositing a graphene layer on a metal substrate surface according to claim 1, characterized in that, Includes at least one of the following features: (1) The mass content of the first metal oxide in the first mixed layer is 0.01-1.5%; (2) The mass content of the first metal oxide in the second mixed layer is 0.05-3.0%; (3) The thickness of the first mixing layer is greater than that of the second mixing layer; (4) The thickness of the first hybrid layer is 0.3-0.95 μm; (5) The thickness of the second hybrid layer is 0.1-0.5 μm.

3. The method for depositing a graphene layer on a metal substrate surface according to claim 1, characterized in that, S1 includes: S1.1, Prepare a first plating solution, the first plating solution comprising a first metal oxide and a first metal ion; S1.2, The metal substrate is placed in the first plating solution, and the first mixed layer is formed on the surface of the metal substrate by electroplating.

4. The method for depositing a graphene layer on a metal substrate surface according to claim 3, characterized in that, The first plating solution includes at least one of the following characteristics: (1) Copper oxide 0.5-1.8 g / L; (2) Cuprous cyanide 50-65 g / L; (3) Potassium cyanide 100-135 g / L; (4) Potassium hydroxide 11-16 g / L; (5) Potassium thiocyanate 12-18 g / L; (6) Potassium sodium tartrate 17-28 g / L; (7) Dispersant 20-35g / L.

5. The method for depositing a graphene layer on a metal substrate surface according to claim 3, characterized in that, In step S1.2, the electroplating current density is 0.2-0.5 A / dm³. 2 ; And / or, the temperature of the first plating solution is 16-24°C; And / or, the pH value of the first plating solution is 7.5-10.

5.

6. The method for depositing a graphene layer on a metal substrate surface according to claim 1, characterized in that, S1 includes: S1.3, Prepare a second plating solution, the second plating solution comprising a first metal oxide and a first metal ion; S1.4, the metal substrate having the first mixed layer is placed in the second plating solution, and the second mixed layer is formed by electroplating on the surface of the first mixed layer.

7. The method for depositing a graphene layer on a metal substrate surface according to claim 6, characterized in that, The second plating solution includes at least one of the following characteristics: (1) Copper oxide 1.0-3.0 g / L; (2) Cuprous cyanide 50-65 g / L; (3) Potassium cyanide 100-135 g / L; (4) Potassium hydroxide 11-16 g / L; (5) Potassium thiocyanate content: 12-18 g / L; (6) Potassium sodium tartrate 17-28 g / L; (7) Dispersant 20-35g / L.

8. The method for depositing a graphene layer on a metal substrate surface according to claim 7, characterized in that, In step S1.4, the electroplating current density is 0.3-0.7 A / dm³. 2 ; And / or, the temperature of the second plating solution is 16-24°C; And / or, the pH value of the second plating solution is 7.5-10.

5.

9. The method for depositing a graphene layer on a metal substrate surface according to claim 1, characterized in that, In step S2, the metal substrate is heated to 850-1050°C at a heating rate of 10-20°C / min.

10. The method for depositing a graphene layer on a metal substrate surface according to claim 1, characterized in that, In S2, the carbon-containing gas includes methane, and the amount of methane introduced is 15-100 sccm.

11. The method for depositing a graphene layer on a metal substrate surface according to claim 10, characterized in that, In step S2, the temperature is increased and a carbon-containing gas, including nitrogen and / or argon, is introduced into an inert gas atmosphere, and the amount of inert gas introduced is 0-1000 sccm.

12. The method for depositing a graphene layer on a metal substrate surface according to claim 10, characterized in that, In step S2, hydrogen gas is introduced simultaneously with the carbon-containing gas, and the amount of hydrogen gas introduced is 5-500 sccm.

13. The method for depositing a graphene layer on a metal substrate surface according to claim 1, characterized in that, In S2, a pre-pyrolysis chamber is provided before the vapor deposition chamber. An oxide-formed plate or particulate carrier is provided in the pre-pyrolysis chamber so that the carbon-containing gas passes through the pre-pyrolysis chamber and then enters the vapor deposition chamber.

14. The method for depositing a graphene layer on a metal substrate surface according to claim 13, characterized in that, The temperature of the pre-pyrolysis chamber is increased to the same level as that of the vapor deposition chamber.

15. A metal-graphene composite conductor, characterized in that, The metal-graphene composite conductor is prepared by the method according to any one of claims 1-14, comprising: Metallic matrix, including a first metal; A metal-graphene composite layer is disposed on at least one surface of the metal substrate; The metal-graphene composite layer includes a first porous metal layer, a second porous metal layer, and a graphene layer. Both the first porous metal layer and the second porous metal layer include the first metal. The first porous metal layer is located between the second porous metal layer and the metal substrate. The graphene layer covers the second porous metal layer and fills the pores in the first porous metal layer and the pores in the second porous metal layer. The porosity of the second porous metal layer is greater than that of the first porous metal layer, and at least the inner wall of the pores and the surface of the adjacent inner wall of the pores are hydrophobic surfaces.

16. The metal-graphene composite conductor according to claim 15, characterized in that, The porosity of the first porous metal layer is 1.5-5%; And / or, the porosity of the second porous metal layer is 4-8%.

17. The metal-graphene composite conductor according to claim 15, characterized in that, The first porous metal layer is configured to be formed by reducing a first mixed layer, and the second porous metal layer is configured to be formed by reducing a second mixed layer; Both the first mixed layer and the second mixed layer are mixed electroplated layers of a first metal and a first metal oxide, and the content of the first metal oxide in the second mixed layer is higher than that in the first mixed layer.

18. The use of a metal-graphene composite conductor as described in any one of claims 15-17 as a wire, cable, or electrical contact.

Images