Composite conductor and preparation method thereof
By using nested structure conductive body and graphene layer filling technology in the copper matrix, the problem of uniform dispersion of graphene and insufficient interface bonding strength in the copper matrix is solved, and efficient electrical conductivity and comprehensive performance improvement is achieved.
Patent Information
- Application Number
- CN202311726593.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-14
- Publication Date
- 2025-06-17
AI Technical Summary
The prior art is difficult to achieve highly uniform dispersion of graphene in the copper matrix and insufficient interfacial bonding strength between graphene and the copper matrix, resulting in the inability and comprehensive performance of graphene-reinforced copper-based composite materials to meet expectations.
A composite conductor structure is adopted, wherein the conductive substrate consists of a plurality of conductive bodies nested in one another in sequence in the first direction, and the conductive bodies alternately in a U-shaped and an inverted U-shaped shape along the second direction, forming a bending region. The conductive connector includes a surface graphene layer and an optional interlayer conductor filled in the gap between the conductive bodies.
Through the nested conductive structures and filling of graphene layers, the connection strength and conductivity between graphene and the conductive substrate are improved, and the conductivity and comprehensive performance of the composite conductor are significantly improved.
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Figure CN120164657A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of conductors, and particularly to a composite conductor and a preparation method thereof. Background Art
[0002] Copper materials are widely used in industries such as electronics and power due to their high electrical conductivity. However, their strength and plasticity still need to be further improved. With the development of industry, higher requirements have been put forward for their electrical conductivity. Currently, it is common to add reinforcing phases to the copper matrix to form copper-based composites to improve the comprehensive properties of copper. Graphene is a two-dimensional nanomaterial composed of a single layer of carbon atoms connected by sp2 hybridization, with excellent mechanical properties, electrical conductivity, and thermal conductivity. Its carrier mobility at room temperature is about 15000 cm 2 / (V·s), and it is considered an ideal reinforcement for copper-based composites. Introducing graphene as a reinforcement into the copper matrix can improve the mechanical properties while increasing the electrical conductivity of the material. It has a high thermal conductivity coefficient, a reduced friction coefficient, and enhanced corrosion resistance, and can be used for electrical contact materials, etc.
[0003] The main problems in preparing graphene-reinforced copper-based composites are how to achieve highly uniform dispersion of graphene in the copper matrix and how to enhance the interfacial bonding strength between graphene and the copper matrix. Existing technologies generally use ball-milled graphene-copper composite powder as raw material to prepare copper-based composites through powder metallurgy. Due to the extremely large density difference between graphene and copper, and the tendency of graphene to agglomerate itself, the dispersion uniformity of graphene in the copper matrix is poor, resulting in the comprehensive properties of graphene-reinforced copper-based composites not reaching the expected performance. In addition, the possibility of the electrical conductivity of graphene copper-based composites exceeding that of copper lies in maintaining the intact two-dimensional monolayer intrinsic characteristics between graphene structures to form a graphene-dominated conductive channel in the composite material. In existing technologies, by stacking multi-layer copper foils with electrochemically deposited graphene on the surface and undergoing a series of process treatments such as hot pressing, a laminated graphene-copper-based composite material is obtained. However, due to subsequent high-temperature pressing, the copper foil-graphene layers are likely to be misaligned, the distribution structure of graphene is damaged, the continuous graphene structure conductive channel is damaged, and at the graphene / copper interface in the longitudinal direction, the movement of electrons is hindered, resulting in the conductive effect not reaching the expected performance.
[0004] Therefore, the electrical conductivity of graphene metal composites needs to be further improved. Summary of the Invention
[0005] In view of this, this application provides a composite conductor and a preparation method thereof.
[0006] The embodiments of the present application are implemented as follows. A composite conductor includes a conductive matrix and a conductive connector. The conductive matrix includes a plurality of conductors nested with each other in sequence along a first direction. The conductors are alternately U-shaped and inverted U-shaped in sequence along a second direction, and the first direction is perpendicular to the second direction. Each conductor includes a first part and a second part arranged in parallel along the second direction, and a third part connecting the first part and the second part. The first part, the second part, and the third part jointly define a bending area.
[0007] Among any two adjacent conductors, the second part of the previous conductor is located in the bending area of the subsequent conductor, and the free end of the second part of the previous conductor abuts against the third part of the subsequent conductor. The first part of the subsequent conductor is located in the bending area of the previous conductor, and the free end of the first part of the subsequent conductor abuts against the third part of the previous conductor. There is a gap between the two adjacent conductors. The conductive connector fills the gap, and the conductive connector includes a surface graphene layer, and the surface graphene layer is disposed on the surfaces of the two adjacent conductors.
[0008] Optionally, in some embodiments of the present application, the conductive connector further includes an interlayer conductor, and the interlayer conductor is disposed between the surface graphene layer on the surface of the previous conductor and the surface graphene layer on the surface of the subsequent conductor.
[0009] Optionally, in some embodiments of the present application, the interlayer conductor includes M interlayer conductive metal layers and N interlayer graphene layers. The M interlayer conductive metal layers and the N interlayer graphene layers are alternately arranged in sequence along a third direction, and the third direction is perpendicular to both the first direction and the second direction. Among them, both M and N are positive integers greater than 2, and M≥N.
[0010] Optionally, in some embodiments of the present application, M and N satisfy M = N + 1, and the uppermost layer of the interlayer conductor along the third direction is the Mth interlayer conductive metal layer.
[0011] Optionally, in some embodiments of the present application, M and N satisfy M = N, and the uppermost layer of the interlayer conductor along the third direction is the Nth interlayer graphene layer.
[0012] Optionally, in some embodiments of the present application, the number of layers of the surface graphene layer and each interlayer graphene layer are respectively 2 to 5 layers, and the thicknesses are respectively 0.6 nm to 1.6 nm; and / or
[0013] The thickness of each interlayer conductive metal layer is respectively 10 μm to 50 μm, and the materials are respectively one or more of copper, silver, copper alloy, and silver alloy; and / or
[0014] The thickness of each conductor is respectively 10 μm to 50 μm, and the materials are respectively one or more of copper, silver, copper alloy, and silver alloy.
[0015] Optionally, in some embodiments of the present application, the distance between the second part of the previous conductor and the first part of the subsequent conductor is 200 μm to 500 μm respectively.
[0016] Optionally, in some embodiments of the present application, the conductive matrix includes at least three continuously nested conductors. Among any three continuously nested conductors, the second part of the previous conductor and the first part of the subsequent conductor are both located in the bending area of the middle conductor, and the distance between the second part of the previous conductor and the first part of the subsequent conductor is 100 μm to 200 μm.
[0017] Correspondingly, an embodiment of the present application further provides a method for preparing a composite conductor, including:
[0018] Providing a conductive matrix, the conductive matrix includes a plurality of conductors nested with each other in sequence along a first direction, the conductors are alternately U-shaped and inverted U-shaped in sequence along a second direction, and the first direction and the second direction are perpendicular; each conductor includes a first part and a second part arranged in parallel along the second direction, and a third part connecting the first part and the second part, and the first part, the second part and the third part jointly define a bending area; among any two adjacent conductors, the second part of the previous conductor is located in the bending area of the subsequent conductor, and the free end of the second part of the previous conductor abuts against the third part of the subsequent conductor, the first part of the subsequent conductor is located in the bending area of the previous conductor, and the free end of the first part of the subsequent conductor abuts against the third part of the previous conductor, and there is a gap between the two adjacent conductors;
[0019] Filling a conductive connector in the gap, the conductive connector includes a surface graphene layer, and the surface graphene layer is arranged on the surfaces of the two adjacent conductors to obtain a composite conductor.
[0020] Optionally, in some embodiments of the present application, filling a conductive connector in the gap includes:
[0021] Growing a surface graphene layer on the surface of each conductor;
[0022] Forming an interlayer conductor between the surface graphene layers of two adjacent conductors to obtain a composite conductor.
[0023] Optionally, in some embodiments of the present application, growing a surface graphene layer on the surface of each conductor includes:
[0024] Introducing a carbon source gas and a first protective gas into the conductive matrix to deposit a surface graphene layer.
[0025] Optionally, in some embodiments of the present application, the carbon source gas includes one or more of hydrocarbon compounds and alcohol compounds; the hydrocarbon compounds include one or more of methane, ethane, propane, ethylene, and acetylene; and / or
[0026] The first protective gas includes one or more of nitrogen, helium, neon, argon, krypton, xenon, and radon; and / or
[0027] The sum of the gas flow rates of the carbon source gas and the first protective gas is 1 sccm to 100 sccm; and / or
[0028] The gas flow rate ratio of the first protective gas to the carbon source gas is (16 to 25):1; and / or
[0029] The pressure for depositing graphene is 500 Pa to 900 Pa; the temperature is 400 °C to 800 °C; the time is 1 min to 8 min.
[0030] Optionally, in some embodiments of the present application, before introducing the carbon source gas and the first protective gas into the conductive substrate, it further includes: introducing a second protective gas into the conductive substrate, heating to a temperature T, and performing an annealing treatment.
[0031] Optionally, in some embodiments of the present application, the second protective gas includes one or more of nitrogen, helium, neon, argon, krypton, xenon, and radon; and / or
[0032] The gas flow rate of the second protective gas is 240 sccm to 350 sccm; and / or
[0033] The heating rate is 12 °C / min to 18 °C / min; and / or
[0034] The temperature T is 1000 °C to 1080 °C; and / or
[0035] The time for the annealing treatment is 0.5 h to 2 h.
[0036] Optionally, in some embodiments of the present application, after growing the surface graphene layer, it further includes: forming a first interlayer conductive metal layer on the surface of the surface graphene layer along a third direction, where the third direction is perpendicular to both the first direction and the second direction.
[0037] Optionally, in some embodiments of the present application, the method for forming the first interlayer conductive metal layer includes: pouring a metal melt on the surface of the surface graphene layer along the third direction, and cooling to form the first interlayer conductive metal layer.
[0038] Optionally, in some embodiments of the present application, the metal melt includes one or more of copper, silver, copper alloys, and silver alloys; and / or
[0039] Cooling includes introducing a cooling gas, and the time for introducing the cooling gas is 20 s to 80 s; the gas flow rate of the cooling gas is 300 sccm to 400 sccm, the temperature is 500 °C to 800 °C, and the material is one or more of nitrogen, helium, neon, argon, krypton, xenon, and radon.
[0040] Optionally, in some embodiments of the present application, the method after growing the surface graphene layer includes: sputtering a conductive metal on the surface of the surface graphene layer along a third direction by chemical vapor deposition to form a first interlayer conductive metal layer.
[0041] Optionally, in some embodiments of the present application, after forming the first interlayer conductive metal layer, it further includes: sequentially and alternately forming a plurality of interlayer graphene layers and a plurality of interlayer conductive metal layers on the surface of the first interlayer conductive metal layer along the third direction; the plurality of interlayer graphene layers and the plurality of interlayer conductive metal layers are sequentially and alternately filled in the gaps between adjacent two conductors.
[0042] For the composite conductor provided by the present application, the mutually nested conductor structures enable the graphene layers to be nested with each other, and the conductors and the graphene layers are connected both horizontally and vertically, which is beneficial for the graphene layers to fully exert the beneficial effects on the conductive matrix and improve the conductive continuity and conductivity of the composite conductor. Description of the Drawings
[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained according to these drawings.
[0044] Figure 1 is a simple schematic diagram of the conductive matrix provided by the embodiment of the present application;
[0045] Figure 2 is a top view schematic diagram of the structure of the composite conductor provided by the embodiment of the present application;
[0046] Figure 3 is a cross-sectional schematic diagram of the structure of the composite conductor provided by the embodiment of the present application along the first direction A-A;
[0047] Figure 4 is a cross-sectional schematic diagram of the structure of the composite conductor provided by the embodiment of the present application along the second direction B-B;
[0048] Figure 5 is a simple schematic diagram of another conductive matrix provided by the embodiment of the present application;
[0049] Figure 6It is a flowchart of a method for preparing a composite conductor provided by an embodiment of the present application.
[0050] Reference numerals:
[0051] Composite conductor - 1; Conductive substrate - 10; Conductor - 11; First part - 111; Second part - 112; Third part - 113; Bending area - 114; Surface graphene layer - 20; Interlayer conductive metal layer - 30; Interlayer graphene layer 40. Detailed implementation manners
[0052] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application. In addition, it should be understood that the specific implementation manners described herein are only used to illustrate and explain the present application, and are not used to limit the present application.
[0053] In the present application, unless otherwise stated, the orientation terms such as "upper" and "lower" generally refer to the upper and lower in the actual use or working state of the device, specifically the drawing direction in the drawings; and "inner" and "outer" refer to the outline of the device. In addition, in the description of the present application, the term "including" means "including but not limited to". The terms first, second, third, etc. are only used as labels and do not impose numerical requirements or establish an order.
[0054] In the present application, "and / or" describes the association relationship of associated objects and indicates that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. Where A and B can be singular or plural.
[0055] In the present application, "at least one" means one or more, and "multiple" means two or more. "At least one kind", "at least one item (piece) below" or similar expressions refer to any combination of these items, including any combination of single item (piece) or plural items (pieces). For example, "at least one item (piece) of a, b, or c", or, "at least one item (piece) of a, b, and c" can both represent: a, b, c, a - b (i.e., a and b), a - c, b - c, or a - b - c, where a, b, and c can be single or multiple respectively.
[0056] The various embodiments of the present application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be construed as a rigid limitation on the scope of the present application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and the individual values within the 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 the individual numbers within the range, such as 1, 2, 3, 4, 5, and 6, and this applies regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.
[0057] The technical solution of the present application is as follows:
[0058] In a first aspect, please refer to Figures 1 to 2 , an embodiment of the present application provides a composite conductor 1, including: a composite conductor 1, including: a conductive matrix 10 and a conductive connector. The conductive matrix 10 includes a plurality of conductors 11 nested with each other in sequence along a first direction. The conductors 11 are alternately U-shaped and inverted U-shaped in sequence along a second direction, and the first direction and the second direction are perpendicular; each conductor includes a first portion 111 and a second portion 112 arranged in parallel along the second direction, and a third portion 113 connecting the first portion 111 and the second portion 112. The first portion 111, the second portion 112, and the third portion 113 together define a bending region 114;
[0059] Among any two adjacent conductors 11, the second portion 112 of the previous conductor 11 is located in the bending region 114 of the subsequent conductor 11, and the free end of the second portion 112 of the previous conductor 11 abuts against the third portion 113 of the subsequent conductor 11. The first portion 111 of the subsequent conductor 11 is located in the bending region 114 of the previous conductor 11, and the free end of the first portion 111 of the subsequent conductor 11 abuts against the third portion 113 of the previous conductor 11. There is a gap between the two adjacent conductors 11; the conductive connector fills the gap, and the conductive connector includes a surface graphene layer 20, and the surface graphene layer 20 is disposed on the surfaces of the two adjacent conductors 11.
[0060] For the composite conductor 1 provided by the present application, the structure of the nested conductors 11 enables the graphene layers to be nested with each other as well. The conductors 11 and the graphene layers are connected both horizontally and vertically, which is beneficial for the graphene layers to fully exert their beneficial effects on the conductive matrix 10 and improve the conductivity continuity and conductivity of the composite conductor 1.
[0061] It can be understood that in the conductive matrix 10, the number of conductors 11 can be 2, 3, or 4 or more.
[0062] In some embodiments, the conductive connector further includes an interlayer conductor disposed between the surface graphene layers 20 on the surface of the previous conductor 11 and the surface graphene layers 20 on the surface of the subsequent conductor 11.
[0063] In some embodiments, referring to Figure 3 and Figure 4 , the interlayer conductor includes M interlayer conductive metal layers 30 and N interlayer graphene layers 40. The M interlayer conductive metal layers 30 and the N interlayer graphene layers 40 are alternately arranged in sequence along a third direction, which is perpendicular to both the first direction and the second direction. Here, both M and N are positive integers greater than 2, and M≥N. It can be understood that the interlayer conductive metal layers 30 can prevent the graphene in the surface graphene layers 20 on the surface of the previous conductor 11 from agglomerating with the graphene in the surface graphene layers 20 on the surface of the subsequent conductor 11, and increase the content of conductive metal, which can further improve the conductivity of the composite conductor 1.
[0064] The multiple interlayer graphene layers 40 and the multiple interlayer conductive metal layers 30 are alternately filled in sequence along the third direction into the gap between two adjacent conductors 11 provided with surface graphene layers 20. It should be noted that multiple interlayer graphene layers 40 and multiple interlayer conductive metal layers 30 are alternately arranged on the surfaces of every two adjacent conductors 11 in sequence. Each interlayer graphene layer 40 is disposed between adjacent interlayer conductive metal layers 30, which can protect the structural integrity of graphene and improve the uniform distribution of graphene in the composite conductor 1, thereby giving full play to the role of graphene in improving the conductivity of the conductive matrix 10.
[0065] Exemplarily, in some embodiments, the interlayer graphene layers 40 include a first interlayer graphene layer, a second interlayer graphene layer, a third interlayer graphene layer... an (N - 1)th interlayer graphene layer, and an Nth interlayer graphene layer.
[0066] In some embodiments, the interlayer conductive metal layers 30 include a first interlayer conductive metal layer, a second interlayer conductive metal layer, a third interlayer conductive metal layer... an (M - 1)th interlayer conductive metal layer, and an Mth interlayer conductive metal layer.
[0067] Furthermore, in some embodiments, N and M satisfy N + 1 = M. The uppermost layer of the interlayer conductor along the third direction is the Mth interlayer conductive metal layer.
[0068] That is to say, in this embodiment, for the same conductor 11, the conductive connector is alternately the first interlayer conductive metal layer, the first interlayer graphene layer, the second interlayer conductive metal layer... the (N - 1)th interlayer graphene layer, the (M - 1)th interlayer conductive metal layer, the Nth interlayer graphene layer, and the Mth interlayer conductive metal layer in sequence along the third direction from bottom to top or from top to bottom.
[0069] In some other embodiments, N and M satisfy N = M, and the topmost layer of the interlayer conductor in the third direction is the Nth interlayer graphene layer.
[0070] That is to say, in this embodiment, for the same conductor 11, the conductive connectors are alternately the first interlayer conductive metal layer, the second interlayer graphene layer, the second interlayer conductive metal layer... the (M - 1)th interlayer conductive metal layer, the (N - 1)th interlayer graphene layer, the Mth interlayer conductive metal layer, and the Nth interlayer graphene layer in sequence from bottom to top or from top to bottom in the third direction.
[0071] In some embodiments, the number of layers of the surface graphene layer 20 and each interlayer graphene layer 40 is respectively 2 to 5 layers, for example, it can be 2 layers, 3 layers, 4 layers or 5 layers. It can be understood that the number of layers of the surface graphene layer 20 and different interlayer graphene layers 40 can be the same or different.
[0072] In some embodiments, the thickness of the surface graphene layer 20 and each interlayer graphene layer 40 is respectively 0.6 nm to 1.6 nm, for example, it can be 0.8 nm, 1 nm, 1.2 nm, 1.4 nm, etc. Within this range, the thickness of the surface graphene layer 20 and the interlayer graphene layer 40 will not agglomerate and the structure will not be damaged due to being too thick, nor will the conductivity of the composite conductor 1 not be improved due to being too thin.
[0073] In some embodiments, the thickness of each interlayer conductive metal layer 30 is respectively 10 μm to 50 μm, for example, it can be 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, etc.
[0074] In some embodiments, the material of each interlayer conductive metal layer 30 is one or several of copper, silver, copper alloy, and silver alloy. Preferably, the material of each interlayer conductive metal layer 30 is copper.
[0075] In some embodiments, the thickness of each conductor 11 is respectively 10 μm to 50 μm, for example, it can be 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, etc.
[0076] It should be noted that the thickness of each conductor 11 and the thickness of each interlayer conductive metal layer 30 can be the same or different.
[0077] Preferably, the thickness of each conductor 11 is the same as the thickness of each interlayer conductive metal layer 30. In this way, it is beneficial for graphene to be more evenly distributed in the composite conductor 1.
[0078] In some embodiments, the material of each conductor 11 is one or several of copper, silver, copper alloy, and silver alloy. Preferably, the material of each conductor 11 is copper. It should be noted that when the material of the conductor 11 is selected from copper alloy or silver alloy, the purity of copper or silver is greater than 98%. In this way, the excellent electrical conductivity of the composite conductor 1 can be ensured.
[0079] In some embodiments, please continue to refer to Figure 1 , the distances between the second part 112 of the previous conductor 11 and the first part 111 of the subsequent conductor 11 are d1 respectively, and the range of d1 is 200μm to 500μm. For example, it can be 250μm, 300μm, 350μm, 400μm, 450μm, etc. In this way, within this range, sufficient space can be provided for the filling of the conductive connector.
[0080] Please refer to Figure 5 , in some embodiments, the conductive substrate 10 includes at least 3 continuously nested conductors 11. Among any three continuously nested conductors 11, the second part 112 of the previous conductor 11 and the first part 111 of the subsequent conductor 11 are both located in the bending area 114 of the middle conductor 11, and the distances between the second part 112 of the previous conductor 11 and the first part 111 of the subsequent conductor 11 are d2 respectively, and the range of d2 is 100μm to 200μm. For example, it can be 110μm, 120μm, 130μm, 140μm, 150μm, 16m, 170μm, 180μm, 190μm, etc. In this way, within this distance range, it is beneficial to provide sufficient space for the filling of the conductive connector between the previous conductor 11 and the subsequent conductor 11.
[0081] In a second aspect, please refer to Figure 6 , the embodiments of the present application further provide a preparation method of the composite conductor 1, including:
[0082] S11. Provide a conductive substrate 10, which includes a plurality of conductors 11 nested with each other in sequence along a first direction. The conductors 11 are alternately U-shaped and inverted U-shaped in sequence along a second direction, and the first direction is perpendicular to the second direction. Each conductor 11 includes a first part 111 and a second part 112 arranged in parallel along the second direction, and a third part 113 connecting the first part 111 and the second part 112. The first part 111, the second part 112 and the third part 113 jointly define a bending area 114. Among any two adjacent conductors 11, the second part 112 of the previous conductor 11 is located in the bending area 114 of the subsequent conductor 11, and the free end of the second part 112 of the previous conductor 11 abuts against the third part 113 of the subsequent conductor 11. The first part 111 of the subsequent conductor 11 is located in the bending area 114 of the previous conductor 11, and the free end of the first part 111 of the subsequent conductor 11 abuts against the third part 113 of the previous conductor 11. There is a gap between the two adjacent conductors 11.
[0083] In some embodiments, the conductor 11 is made by bending a metal foil.
[0084] Further, the metal foil includes one or more of an electrolytically polished copper foil, a rolled copper foil, and a single crystal copper foil.
[0085] In some embodiments, the surface of the metal foil is modified and flat. Thus, it is beneficial to the deposition of graphene.
[0086] In some embodiments, the thickness of the metal foil is 10 μm to 50 μm, and for example, it can be 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, etc. If the thickness of the metal foil is too thick, it will cause graphene to be unable to be effectively deposited to obtain a continuous graphene layer 20; if the thickness of the metal foil is too thin, it is easy to break during bending, reducing the operability.
[0087] In some embodiments, the aspect ratio of the metal foil is greater than 50. It can be understood that in other embodiments, metal foils with corresponding aspect ratios can be selected according to requirements.
[0088] It can be understood that in the conductive substrate 10, there is a gap between adjacent conductors 11. Therefore, a fixing device can be used to fix the third part 113 of each conductor 11 to obtain a stable conductive substrate 10.
[0089] In some embodiments, the preparation method of the composite conductor 1 further includes:
[0090] S12. Fill a conductive connector in the gap. The conductive connector includes a surface graphene layer 20, and the surface graphene layer 20 is disposed on the surfaces of the two adjacent conductors 11 to obtain the composite conductor 1.
[0091] In some embodiments, filling the gap with a conductive connector includes:
[0092] S121. Growing a surface graphene layer 20 on the surface of each conductor 11;
[0093] S122. Forming an interlayer conductor between the surface graphene layers 20 of two adjacent conductors 11 to obtain a composite conductor.
[0094] It can be understood that growing the surface graphene layer 20 on the surface of each conductor 11 can adopt conventional methods in the art, such as chemical vapor deposition, mechanical exfoliation, redox method, intercalation method, etc.
[0095] In at least one embodiment, the method for growing the graphene layer on the surface of each conductor 11 is chemical vapor deposition, and the chemical vapor deposition includes: introducing a carbon source gas and a first protective gas into the conductive substrate 10 to deposit graphene.
[0096] In some embodiments, the carbon source gas includes one or more of hydrocarbon compounds and alcohol compounds.
[0097] Specifically, the hydrocarbon compounds include one or more of methane, ethane, propane, ethylene, and acetylene.
[0098] In some embodiments, the first protective gas includes inert gases. The inert gases include one or more of nitrogen, helium, neon, argon, krypton, xenon, and radon.
[0099] In some embodiments, the sum of the gas flow rates of the carbon source gas and the first protective gas is 1 sccm to 100 sccm, and for example, it can be 10 sccm, 20 sccm, 30 sccm, 40 sccm, 50 sccm, 60 sccm, 70 sccm, 80 sccm, 90 sccm, etc.
[0100] In some embodiments, the gas flow rate ratio of the first protective gas to the carbon source gas is (16 - 25):1, and for example, it can be 18:1, 19:1, 20:1, 22:1, 24:1, etc.
[0101] In some embodiments, the pressure for depositing graphene is 500 Pa to 900 Pa, and for example, it can be 600 Pa, 700 Pa, 800 Pa, etc.; the temperature is 400 °C to 800 °C, and for example, it can be 500 °C, 600 °C, 700 °C, etc.; the time is 1 min to 8 min, and for example, it can be 2 min, 3 min, 4 min, 5 min, 6 min, 7 min, etc. Thus, it is beneficial to grow a continuous graphene layer 20 on the surface of the conductor 11, thereby improving the conductivity of the composite conductor 1.
[0102] In some embodiments, before introducing a carbon source gas and a first protective gas into the conductive substrate 10, a pretreatment of the conductive substrate 10 is further included. It can be understood that the pretreatment of the conductive substrate 10 can make the surface of the conductive substrate 10 smooth, which is beneficial to the deposition and tight combination of graphene.
[0103] Further, the pretreatment of the conductive substrate 10 includes: introducing a second protective gas into the conductive substrate 10, heating it to a temperature T, and performing an annealing treatment.
[0104] In some embodiments, the second protective gas includes an inert gas. The inert gas includes one or more of nitrogen, helium, neon, argon, krypton, xenon, and radon.
[0105] In some embodiments, the gas flow rate of the second protective gas is 240 sccm to 350 sccm, and for example, it can be 260 sccm, 280 sccm, 300 sccm, 320 sccm, 340 sccm, etc.
[0106] In some embodiments, the heating rate is 12 °C / min to 18 °C / min, and for example, it can be 13 °C / min, 14 °C / min, 15 °C / min, 16 °C / min, 17 °C / min, etc.
[0107] In some embodiments, the temperature T is 1000 °C to 1080 °C, and for example, it can be 1010 °C, 1020 °C, 1030 °C, 1040 °C, 1050 °C, 1060 °C, 1070 °C, etc.
[0108] In some embodiments, the annealing treatment time is 0.5 h to 2 h, and for example, it can be 0.8 h, 1 h, 1.2 h, 1.5 h, 1.8 h, etc.
[0109] In some embodiments, after growing the surface graphene layer 20, it further includes: forming a first interlayer conductive metal layer on the surface of the surface graphene layer 20 along a third direction, and the third direction is perpendicular to both the first direction and the second direction.
[0110] In some embodiments, the method of forming the first interlayer conductive metal layer on the surface of the surface graphene layer 20 includes: pouring a metal melt on the surface of the surface graphene layer 20 along the third direction, and cooling to form the first interlayer conductive metal layer 30. By using the method of pouring the metal melt to prepare the interlayer conductive metal layer 30, the metal melt has good fluidity and can fully contact the surface graphene layer 20 and form a continuous interlayer conductive metal layer 30.
[0111] In some embodiments, the metal melt includes one or more of copper, silver, copper alloy, and silver alloy. The material of the metal melt and the material of the conductor 11 can be the same or different.
[0112] Preferably, the material of the molten metal is the same as that of the conductor 11. In this way, it is beneficial to the uniformity of the conductivity of each part in the composite conductor 1.
[0113] In some embodiments, the cooling includes introducing a cooling gas.
[0114] Further, the time for introducing the cooling gas is 20 s to 80 s, for example, it can be 30 s, 40 s, 50 s, 60 s, 70 s, etc. The gas flow rate of the cooling gas is 300 sccm to 400 sccm, for example, it can be 320 sccm, 340 sccm, 360 sccm, 380 sccm, etc. The temperature is 500 °C to 800 °C, for example, it can be 550 °C, 600 °C, 650 °C, 710 °C, 750 °C, etc. The material of the cooling gas is an inert gas, and the inert gas includes one or more of nitrogen, helium, neon, argon, krypton, xenon, and radon. In this way, it is beneficial to the cooling of the molten metal and its solidification into the conductive metal layer 30.
[0115] In some other embodiments, the method for forming the first interlayer conductive metal layer 30 on the surface of the surface graphene layer 20 includes: sputtering a conductive metal on the surface of the surface graphene layer 20 along the third direction by chemical vapor deposition to form the first interlayer conductive metal layer 30. The process of sputtering the conductive metal by chemical vapor deposition is controllable, which can make the thickness of the first interlayer conductive metal layer 30 uniform and the structure complete, and can be tightly connected to the surface graphene layer.
[0116] In some embodiments, after forming the first interlayer conductive metal layer, it further includes: alternately forming a plurality of interlayer graphene layers and a plurality of interlayer conductive metal layers on the surface of the first interlayer conductive metal layer along the third direction; the plurality of interlayer graphene layers and the plurality of interlayer conductive metal layers are alternately filled in the gap between two adjacent conductors 11.
[0117] The present application will be specifically described below through specific embodiments. The following embodiments are only partial embodiments of the present application and do not limit the present application.
[0118] Embodiment 1
[0119] This embodiment provides a composite conductor, and its preparation method is as follows:
[0120] Provide a conductive substrate, which includes 2 mutually nested and bent copper foils fixed by a fixing device. The thickness of each bent copper foil is 30 μm, and there is a gap between two adjacent bent copper foils;
[0121] Place the conductive substrate in a mold, introduce nitrogen with a gas flow rate of 300 sccm, heat it to 1050 °C at a heating rate of 15 °C / min for annealing; after annealing, introduce a mixed gas of methane and argon with a gas flow rate of 50 sccm, and deposit for 5 min under the conditions of a pressure of 700 Pa and a temperature of 500 °C to form 3 layers of surface graphene layers, obtaining a composite conductor.
[0122] Example 2
[0123] This example provides a composite conductor, and its preparation method is as follows:
[0124] Provide a conductive substrate, which includes 2 nested bent copper foils fixed by a fixing device. The thickness of each bent copper foil is 30 μm, and there is a gap between two adjacent bent copper foils;
[0125] Place the conductive substrate in a mold, introduce nitrogen with a gas flow rate of 300 sccm, heat it to 1050 °C at a heating rate of 15 °C / min for annealing; after annealing, introduce a mixed gas of methane and argon with a gas flow rate of 50 sccm, and deposit for 5 min under the conditions of a pressure of 700 Pa and a temperature of 500 °C to form 3 layers of surface graphene layers;
[0126] Inject copper liquid, introduce cooling gas nitrogen at a temperature of 600 °C for 60 s, and conduct fluid flow casting of the copper liquid by gravity pressurization to form a first interlayer conductive metal layer with a thickness of 30 μm, obtaining a composite conductor.
[0127] Example 3
[0128] This example provides a composite conductor, and its preparation method is as follows:
[0129] Provide a conductive substrate, which includes 3 nested bent copper foils fixed by a fixing device. The thickness of each bent copper foil is 30 μm, and there is a gap between any two adjacent bent copper foils;
[0130] Place the conductive substrate in a mold, introduce nitrogen with a gas flow rate of 300 sccm, heat it to 1050 °C at a heating rate of 15 °C / min for annealing; after annealing, introduce a mixed gas of methane and argon with a gas flow rate of 50 sccm, and deposit for 5 min under the conditions of a pressure of 700 Pa and a temperature of 500 °C to form 3 layers of surface graphene layers;
[0131] Inject copper liquid, introduce cooling gas nitrogen at a temperature of 600 °C for 60 s, and conduct fluid flow casting of the copper liquid by gravity pressurization to form a first interlayer conductive metal layer with a thickness of 30 μm, obtaining a composite conductor.
[0132] Example 4
[0133] This example provides a composite conductor, and its preparation method is as follows:
[0134] Step 1: Provide a conductive substrate, which includes 3 nested bent copper foils fixed by a fixing device. The thickness of each bent copper foil is 30 μm, and there is a gap between any two adjacent bent copper foils;
[0135] Step 2: Place the conductive substrate in a mold, introduce nitrogen, the gas flow rate of nitrogen is 300 sccm, heat it to 1050 °C at a heating rate of 15 °C / min for annealing treatment; after the annealing is completed, introduce a mixed gas of methane and argon, the gas flow rate of the mixed gas is 50 sccm, and deposit for 5 min under the conditions of a pressure of 700 Pa and a temperature of 500 °C to form 3 layers of surface graphene layers;
[0136] Step 3: Inject molten copper, introduce cooling gas nitrogen at a temperature of 600 °C for 60 s, and perform fluid flow casting of the molten copper by gravity pressurization to form a first interlayer conductive metal layer with a thickness of 30 μm;
[0137] Repeat Step 2 and Step 3 once to make the graphene and the conductive metal of the conductive metal layer fill all the gaps in the conductive substrate, and obtain the composite conductor.
[0138] Example 5
[0139] This example provides a composite conductor, and its preparation method is as follows:
[0140] Step 1: Provide a conductive substrate, which includes 10 nested bent copper foils fixed by a fixing device. The thickness of each bent copper foil is 30 μm, and there is a gap between any two adjacent bent copper foils;
[0141] Step 2: Place the conductive substrate in a mold, introduce nitrogen, the gas flow rate of nitrogen is 300 sccm, heat it to 1050 °C at a heating rate of 15 °C / min for annealing treatment; after the annealing is completed, introduce a mixed gas of methane and argon, the gas flow rate of the mixed gas is 50 sccm, and deposit for 5 min under the conditions of a pressure of 700 Pa and a temperature of 500 °C to form 3 layers of surface graphene layers;
[0142] Step 3: Inject molten copper, introduce cooling gas nitrogen at a temperature of 600 °C for 60 s, and perform fluid flow casting of the molten copper by gravity pressurization to form a first interlayer conductive metal layer with a thickness of 30 μm;
[0143] Repeat steps 2 and 3 nine times to allow the conductive metal of the graphene and the conductive metal layer to fill all the gaps in the conductive matrix, obtaining a composite conductor.
[0144] Example 6
[0145] This example provides a composite conductor, and its preparation method is as follows:
[0146] Provide a conductive matrix, which includes three nested bent copper foils fixed by a fixing device. The thickness of each bent copper foil is 30 μm, and there are gaps between any two adjacent bent copper foils;
[0147] Place the conductive matrix in a mold, introduce nitrogen, with the gas flow rate of nitrogen being 300 sccm, heat it to 1050 °C at a heating rate of 15 °C / min for annealing; after the annealing is completed, introduce a mixed gas of methane and argon, with the gas flow rate of the mixed gas being 50 sccm, deposit for 5 min under the conditions of a pressure of 700 Pa and a temperature of 500 °C to form three layers of surface graphene layers;
[0148] Adopt PVD sputtering to deposit copper on the surface graphene layer to form a first interlayer conductive metal layer with a thickness of 30 μm, obtaining a composite conductor.
[0149] Example 7
[0150] This example provides a composite conductor, and its preparation method is as follows:
[0151] Provide a conductive matrix, which includes three nested bent silver foils fixed by a fixing device. The thickness of each bent silver foil is 30 μm, and there are gaps between any two adjacent bent silver foils;
[0152] Place the conductive matrix in a mold, introduce nitrogen, with the gas flow rate of nitrogen being 300 sccm, heat it to 1050 °C at a heating rate of 15 °C / min for annealing; after the annealing is completed, introduce a mixed gas of methane and argon, with the gas flow rate of the mixed gas being 50 sccm, deposit for 5 min under the conditions of a pressure of 700 Pa and a temperature of 500 °C to form three layers of surface graphene layers;
[0153] Inject silver liquid, introduce cooling gas nitrogen at a temperature of 600 °C for 60 s, and conduct fluid flow casting of the silver liquid by means of gravity pressurization to form a first interlayer conductive metal layer with a thickness of 30 μm, obtaining a composite conductor.
[0154] Comparative Example 1
[0155] This comparative example provides a composite conductor, and its preparation method is as follows:
[0156] Mix copper powder and graphene and ball mill. Obtain a composite conductor.
[0157] Comparative Example 2
[0158] This comparative example provides a composite conductor, and its preparation method is as follows:
[0159] A graphene layer is prepared on the surface of a copper foil by chemical vapor deposition to obtain a composite conductor.
[0160] The thermal conductivity and electrical conductivity of the composite conductors of Examples 1 to 7 and Comparative Examples 1 to 2 are measured. Among them, the test method for electrical conductivity refers to T / CSTM00591-2022, and the test method for thermal conductivity refers to GB / T22588-2008. The obtained results are shown in Table 1.
[0161] Table 1
[0162]
[0163] It can be seen from Table 1 that for the composite conductor with the structure provided by this application, both the electrical conductivity and the thermal conductivity are improved compared with Comparative Examples 1 to 2. This is because in the composite conductor provided by this application, a tight connection is formed between graphene and the conductive metal (copper / silver), and graphene gives full play to its beneficial effects on the conductive metal.
[0164] The above has introduced in detail the composite conductor and its preparation method provided by this application. Specific examples are used in this article to elaborate on the principle and implementation manner of this application. The description of the above embodiments is only used to help understand the method and its core idea of this application; at the same time, for those skilled in the art, according to the idea of this application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to this application.
Claims
1. A composite conductor, characterized in that, It includes a conductive substrate and a conductive connector. The conductive substrate includes a plurality of conductors nested with each other in sequence along a first direction. The conductors are alternately U-shaped and inverted U-shaped in sequence along a second direction, and the first direction is perpendicular to the second direction. Each conductor includes a first part and a second part arranged in parallel along the second direction, and a third part connecting the first part and the second part. The first part, the second part and the third part jointly define a bending area. Among any two adjacent conductors, the second part of the previous conductor is located in the bending area of the subsequent conductor, and the free end of the second part of the previous conductor abuts against the third part of the subsequent conductor. The first part of the subsequent conductor is located in the bending area of the previous conductor, and the free end of the first part of the subsequent conductor abuts against the third part of the previous conductor. There is a gap between the two adjacent conductors. The conductive connector fills the gap. The conductive connector includes a surface graphene layer, and the surface graphene layer is arranged on the surfaces of the two adjacent conductors.
2. The composite conductor according to claim 1, characterized in that, The conductive connector further includes an interlayer conductor, and the interlayer conductor is arranged between the surface graphene layer on the surface of the previous conductor and the surface graphene layer on the surface of the subsequent conductor.
3. The composite conductor according to claim 2, characterized in that, The interlayer conductor includes M interlayer conductive metal layers and N interlayer graphene layers. The M interlayer conductive metal layers and the N interlayer graphene layers are alternately arranged in sequence along a third direction. The third direction is perpendicular to both the first direction and the second direction. Among them, both M and N are positive integers greater than 2, and M≥N.
4. The composite conductor according to claim 3, characterized in that, The N and the M satisfy M = N + 1, and the topmost layer of the interlayer conductor along the third direction is the Mth interlayer conductive metal layer.
5. The composite conductor according to claim 3, characterized in that, The N and the M satisfy M = N, and the topmost layer of the interlayer conductor along the third direction is the Nth interlayer graphene layer.
6. The composite conductor according to claim 3, characterized in that, The number of layers of the surface graphene layer and each interlayer graphene layer is 2 to 5 layers respectively, and the thicknesses are 0.6nm to 1.6nm respectively; and / or The thickness of each interlayer conductive metal layer is 10μm to 50μm respectively, and the materials are one or several of copper, silver, copper alloy, and silver alloy respectively; and / or The thickness of each conductor is 10μm to 50μm respectively, and the materials are one or several of copper, silver, copper alloy, and silver alloy respectively.
7. The composite conductor according to claim 1, characterized in that, The distance between the second part of the previous conductor and the first part of the subsequent conductor is 200μm to 500μm respectively.
8. The composite conductor according to claim 1, characterized in that, The conductive substrate includes at least 3 continuously nested conductors. Among any three continuously nested conductors, the second part of the previous conductor and the first part of the subsequent conductor are both located in the bending area of the middle conductor, and the distance between the second part of the previous conductor and the first part of the subsequent conductor is 100μm to 200μm.
9. A method for preparing a composite conductor, characterized in that, It includes: A conductive substrate is provided. The conductive substrate includes a plurality of conductors nested with each other in sequence along a first direction. The conductors are alternately U-shaped and inverted U-shaped in sequence along a second direction, and the first direction is perpendicular to the second direction. Each conductor includes a first portion and a second portion arranged in parallel along the second direction, and a third portion connecting the first portion and the second portion. The first portion, the second portion, and the third portion jointly define a bending region. Among any two adjacent conductors, the second portion of the previous conductor is located in the bending region of the subsequent conductor, and the free end of the second portion of the previous conductor abuts against the third portion of the subsequent conductor. The first portion of the subsequent conductor is located in the bending region of the previous conductor, and the free end of the first portion of the subsequent conductor abuts against the third portion of the previous conductor. There is a gap between the two adjacent conductors. A conductive connecting body is filled in the gap. The conductive connecting body includes a surface graphene layer, and the surface graphene layer is disposed on the surfaces of the two adjacent conductors to obtain a composite conductor.
10. The preparation method according to claim 9, characterized in that, The filling of the conductive connecting body in the gap includes: Growing the surface graphene layer on the surface of each conductor; Forming an interlayer conductor between the surface graphene layers of two adjacent conductors to obtain the composite conductor.
11. The preparation method according to claim 10, characterized in that, The growing of the surface graphene layer on the surface of each conductor includes: Introducing a carbon source gas and a first protective gas into the conductive substrate to deposit the surface graphene layer.
12. The preparation method according to claim 11, characterized in that, The carbon source gas includes one or more of hydrocarbon compounds and alcohol compounds; the hydrocarbon compounds include one or more of methane, ethane, propane, ethylene, and acetylene; and / or The first protective gas includes one or more of nitrogen, helium, neon, argon, krypton, xenon, and radon; and / or The sum of the gas flow rates of the carbon source gas and the first protective gas is 1 sccm to 100 sccm; and / or The gas flow rate ratio of the first protective gas to the carbon source gas is (16 - 25):1; and / or The pressure for depositing graphene is 500 Pa to 900 Pa; the temperature is 400 °C to 800 °C; and the time is 1 min to 8 min.
13. The preparation method according to claim 11, characterized in that, Before introducing the carbon source gas and the first protective gas into the conductive substrate, it further includes: introducing a second protective gas into the conductive substrate, heating it to a temperature T, and performing an annealing treatment.
14. The preparation method according to claim 13, characterized in that, The second protective gas includes one or more of nitrogen, helium, neon, argon, krypton, xenon, and radon; and / or The gas flow rate of the second protective gas is 240 sccm to 350 sccm; and / or The heating rate is 12 °C / min to 18 °C / min; and / or The temperature T is 1000 °C to 1080 °C; and / or The time for the annealing treatment is 0.5 h to 2 h.
15. The preparation method according to claim 11, wherein, After growing the surface graphene layer, it further includes: forming a first interlayer conductive metal layer on the surface of the surface graphene layer along a third direction, and the third direction is perpendicular to both the first direction and the second direction.
16. The preparation method according to claim 15, wherein, The method for forming the first interlayer conductive metal layer comprises: pouring a molten metal on the surface of the surface graphene layer along the third direction, cooling, and forming the first interlayer conductive metal layer.
17. The preparation method according to claim 16, wherein, The molten metal includes one or more of copper, silver, copper alloy, and silver alloy; and / or The cooling includes introducing cooling gas, and the time of introducing cooling gas is 20s to 80s; the gas flow rate of the cooling gas is 300sccm to 400sccm, the temperature is 500℃ to 800℃, and the material is one or more of nitrogen, helium, neon, argon, krypton, xenon, and radon.
18. The preparation method according to claim 15, wherein, The method after growing the surface graphene layer includes: sputtering a conductive metal on the surface of the surface graphene layer along the third direction using a vapor deposition method to form a first interlayer conductive metal layer.
19. The preparation method according to claim 15, wherein, After forming the first interlayer conductive metal layer, the method further includes: alternately forming a plurality of interlayer graphene layers and a plurality of interlayer conductive metal layers on the surface of the first interlayer conductive metal layer along the third direction; and alternately filling the gap between two adjacent conductors with the plurality of interlayer graphene layers and the plurality of interlayer conductive metal layers.