High-performance dendritic silver and carbon-based material composite material as well as preparation method and application thereof
By optimizing the composite ratio and preparation process of dendritic silver and carbon-based materials, a composite material with high electrical conductivity, thermal conductivity and electromagnetic shielding is formed, which solves the problem of insufficient material performance in the existing technology and realizes the application of high-performance flexible electronic devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-29
- Publication Date
- 2026-03-13
AI Technical Summary
Existing carbon-based and metallic materials suffer from problems such as difficulty in achieving both electrical and thermal conductivity, insufficient electromagnetic shielding performance, poor flexibility, and low stability, which limit their application in high-power electronic devices, wearable devices, and high-frequency communication equipment.
By optimizing the mass ratio of dendritic silver to carbon-based materials (0.5-0.7:1) and the preparation process, high-performance composite materials were prepared, including dispersion treatment and heat treatment, forming a highly efficient conductive, thermally conductive and electromagnetically shielding network.
The composite material exhibits high electrical conductivity (1.2×10⁵ S/cm), high thermal conductivity (over 1400 W/mK), high electromagnetic shielding effectiveness (greater than 40 dB), and excellent flexibility (bending radius less than 5 mm), significantly improving the overall performance of the material.
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Figure CN121649385A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of materials science and technology, specifically to a high-performance dendritic silver-carbon-based composite material, its preparation method, and its applications. Background Technology
[0002] In materials science, applications in electrical conductivity, thermal conductivity, and electromagnetic shielding have long relied on single or simple combinations of carbon-based materials and metallic materials. Carbon-based materials such as graphene and carbon nanotubes have been extensively studied due to their unique physical properties. Graphene films can achieve thermal conductivity of up to 1000 W / mK and electrical conductivity of approximately 10⁻⁶. 4 S / cm, while carbon nanotubes exhibit excellent mechanical strength and electrical conductivity. Metallic materials such as silver have extremely high electrical conductivity (up to 1.6 × 10⁻⁶). 5 (S / cm), but its electromagnetic shielding effectiveness is less than 35dB. These materials have been widely used in electronic devices, thermal management systems, and electromagnetic shielding devices, such as as core components in flexible circuits, sensors, and 5G communication equipment.
[0003] While existing technologies offer fundamental performance, significant bottlenecks exist in practical applications. Firstly, achieving both electrical and thermal conductivity is difficult: although graphene possesses high thermal conductivity, its electrical conductivity is far lower than that of metallic silver; conversely, silver's high electrical conductivity cannot be effectively converted into thermal conductivity, resulting in insufficient performance in scenarios requiring dual functions (such as heat dissipation in high-power electronic devices). Experimental data shows that the electrical conductivity of a single graphene material is only about 10. 4 Its thermal conductivity is 1000 W / mK, while that of pure silver is as high as 1.6 × 10⁻⁶ W / cm. 5 While the thermal conductivity is high (S / cm), it is difficult to exceed 1000 W / mK, hindering synergistic optimization. Secondly, electromagnetic shielding performance has an upper limit: existing metal-based materials generally have shielding effectiveness below 35 dB, failing to meet the high-efficiency shielding (>40 dB) requirements of high-frequency communications (such as 6G or IoT devices), especially in the 1-10 GHz band where material attenuation is insufficient. Thirdly, poor flexibility and susceptibility to breakage are prominent issues: the bending radius of metal materials is typically greater than 10 mm, making them prone to cracking or failure under repeated bending stress, limiting their application in wearable devices. Fourthly, insufficient stability: carbon-based materials tend to aggregate over time, leading to decreased dispersion and affecting long-term performance.
[0004] Therefore, there is an urgent need for a novel composite material that, through innovative formulation and processing, achieves multi-objective optimization of electrical conductivity, thermal conductivity, shielding, flexibility, and stability. This invention aims to overcome these bottlenecks and provide a highly efficient, stable, and multifunctional material system. Summary of the Invention
[0005] The technical problem to be solved by this invention is to provide a high-performance dendritic silver and carbon-based composite material, its preparation method and application. The composite material prepared by this invention through optimization of material ratio and process parameters solves the problems of difficulty in balancing conductivity and thermal conductivity, insufficient shielding effectiveness, poor flexibility and low stability in the prior art. It is applicable to the fields of high-efficiency conductive, thermally conductive, electromagnetic shielding and flexible electronic devices.
[0006] This invention is implemented as follows: A high-performance dendritic silver and carbon-based composite material, wherein the raw materials of the composite material include dendritic silver powder and carbon-based material, wherein the mass ratio of dendritic silver to carbon-based material is 0.5-0.7:1, and the particle size of the dendritic silver powder is 1-10 μm.
[0007] Furthermore, the mass ratio of dendritic silver to carbon-based materials is 0.5-0.7:1.
[0008] Furthermore, the dendritic silver powder has a purity of 99.9% or higher.
[0009] Furthermore, the carbon-based material is at least one of graphene or carbon nanotubes.
[0010] Furthermore, the graphene has a thickness of less than 1 nm, an area greater than 100 μm², and a purity of over 98%. The carbon nanotubes have a diameter of 1-5 nm, a length greater than 5 μm, and a purity of over 90%.
[0011] Furthermore, the electrical conductivity of the composite material is at most 1.2 × 10⁻⁶. 5 The shielding performance has the following properties: S / cm, thermal conductivity exceeding 1400 W / mK, electromagnetic shielding effectiveness greater than 40 dB, bending radius less than 5 mm, and relative dispersion stability greater than 0.95.
[0012] Furthermore, the preparation method of the high-performance dendritic silver and carbon-based composite material includes the following steps: a. Mix dendritic silver powder and carbon-based materials in an ethanol solution at a ratio of 0.5-0.7:1; b. Use an ultrasonic disperser at a power of 150~250 W and a frequency of 30~70 kHz for 5~60 minutes to disperse the particles; c. Apply the mixed solution to the substrate surface using a spin coater and dry it in a vacuum environment at a temperature of 60~120℃ for 0.5~1.5 hours; d. Perform heat treatment in a vacuum heat treatment furnace at a temperature of 120~170℃ for 1~3 hours.
[0013] Furthermore, the specific steps are as follows: a. Mix dendritic silver powder and carbon-based materials in an ethanol solution at a ratio of 0.5-0.7:1; b. Dispersion was performed using an ultrasonic disperser at a power of 200 W and a frequency of 40 kHz for 30 minutes; c. Apply the mixed solution to the substrate surface using a spin coater and dry it in a vacuum environment at 80°C for 1 hour. d. Perform heat treatment in a vacuum heat treatment furnace at a temperature of 150°C for 2 hours.
[0014] Furthermore, the high-performance dendritic silver and carbon-based composite material is used in flexible electronic devices, electromagnetic shielding devices, or high thermal conductivity heat sinks.
[0015] Furthermore, the composite material achieves a shielding effectiveness of greater than 40 dB in electromagnetic shielding.
[0016] The present invention has the following advantages: This invention utilizes the unique morphology of dendritic silver (particle size 1-10 μm) and the synergistic effect of carbon-based materials (such as graphene or carbon nanotubes) to form a composite material with highly efficient electrical and thermal conductivity networks at a specific ratio (0.5-0.7). The composite material of this invention possesses the following excellent properties: a conductivity as high as approximately 1.2 × 10⁻⁶. 5 The composite material exhibits excellent properties, including a thermal conductivity exceeding 1400 W / mK, electromagnetic shielding effectiveness greater than 40 dB, a bending radius less than 5 mm, and long-term dispersion stability (relative value >0.95). This composite material is suitable for applications in high-efficiency electrical conductivity, thermal conductivity, electromagnetic shielding, and flexible electronic devices, significantly improving overall performance compared to existing technologies (electrical conductivity increased by approximately 10 times, thermal conductivity increased by more than 50%, and shielding effectiveness increased by more than 33%). Attached Figure Description
[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0018] Figure 1 This is a schematic diagram illustrating the change in conductivity with the proportion of dendritic silver in an embodiment of the present invention.
[0019] Figure 2 This is a schematic diagram illustrating the change in thermal conductivity with the proportion of dendritic silver in an embodiment of the present invention.
[0020] Figure 3 This is a schematic diagram illustrating the change in electromagnetic shielding effectiveness with the proportion of dendritic silver in an embodiment of the present invention.
[0021] Figure 4 This is a schematic diagram illustrating the variation of flexibility with the proportion of dendritic silver in an embodiment of the present invention.
[0022] Figure 5This is a schematic diagram illustrating the change in material stability with the proportion of dendritic silver in an embodiment of the present invention. Detailed Implementation
[0023] The following will be combined with the appendix Figure 1-5 The technical solution of the present invention will be clearly and completely described in detail with specific embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products. Example
[0024] 1. Material preparation The composite material consists of dendritic silver powder and carbon-based materials: the dendritic silver powder has a particle size of 1-10 μm and a purity of 99.9%; the graphene has a thickness of less than 1 nm, an area of more than 100 μm², and a purity of 98%; or the carbon nanotubes have a diameter of 1-5 nm, a length of more than 5 μm, and a purity of 90%. These parameters ensure the material has a high specific surface area and active sites.
[0025] 2. Decentralized processing Dendritic silver and carbon-based material (graphene) were mixed in an ethanol solution at a ratio of 0-1:1. The mixture was then treated with an ultrasonic disperser (200 W, 40 kHz) for 30 minutes to ensure uniform distribution. This step optimized particle dispersion and prevented aggregation.
[0026] 3. Coating and Molding The mixed solution was coated onto the substrate surface using a spin coater (1000 rpm, 60 seconds), and then dried in a vacuum environment (80°C, 1 hour). This process forms a uniform film with controllable thickness.
[0027] 4. Heat treatment The samples were placed in a vacuum heat treatment furnace (150°C, 2 hours) to enhance the structural stability and interfacial bonding of the material. This process significantly improved the electrical and thermal conductivity.
[0028] 5. Experimental Evaluation Performance was verified through standardized testing: Conductivity testing: Conductivity was measured using the four-probe method. See details... Figure 1 . Figure 1 The results show that when the dendritic silver ratio is 0.6, the conductivity reaches a peak of approximately 1.2 × 10⁻⁶. 5 The S / cm indicates that an optimal conductive network has been formed.
[0029] Thermal conductivity testing: Thermal conductivity is measured using a heat flow meter. See details. Figure 2 . Figure 2 The results show that with a dendritic silver ratio of 0.5, the thermal conductivity exceeds 1400 W / mK, demonstrating efficient heat transfer.
[0030] Electromagnetic shielding effectiveness testing: An electromagnetic shielding effectiveness tester is used. See details. Figure 3 . Figure 3 The results show that when the dendritic silver ratio is higher than 0.7, the shielding effectiveness reaches 45 dB, which is better than existing technologies.
[0031] Flexibility testing: Bending integrity is assessed using a flexibility testing machine. See details... Figure 4 . Figure 4 The results show that when the dendritic silver ratio is 0.3, the maximum strain reaches 5% and the bending radius is less than 5 mm.
[0032] Stability testing: Dispersion stability was analyzed using a dynamic light scattering instrument; see details below. Figure 5 . Figure 5 The results show that when the dendritic silver ratio is 0.2, the relative stability value reaches a peak of 0.95.
[0033] 6. Application Examples This composite material can be used in: flexible displays (bending radius <5 mm), high-frequency electromagnetic shielding films (>40 dB), and high-efficiency heat sinks (thermal conductivity >1400 W / mK). Experiments have shown that within a ratio range of 0.5-0.7, the material lifespan is extended by more than 50%.
[0034] In summary, the present invention has the following advantages: 1. The optimal ratio range of dendritic silver to carbon-based materials in this invention (0.5-0.7:1) has been verified by experimental data to achieve multi-objective optimization of performance.
[0035] 2. SEM and TEM analyses confirmed that the highly efficient conductive and thermally conductive network structure formed by the dendritic silver morphology optimizes the material's performance in diverse application scenarios.
[0036] 3. This invention significantly improves material properties by optimizing the preparation process, which includes dispersion treatment (200 W, 30 minutes) and heat treatment (150°C, 2 hours).
[0037] In summary, the composite material of the present invention exhibits the following high performance: a conductivity as high as approximately 1.2 × 10⁻⁶. 5With a strength of S / cm, thermal conductivity exceeding 1400 W / mK, electromagnetic shielding effectiveness greater than 40 dB, bending radius less than 5 mm, and long-term dispersion stability (relative value >0.95), this technology significantly improves overall performance compared to existing technologies (conductivity increased by approximately 10 times, thermal conductivity increased by more than 50%, and shielding effectiveness increased by more than 33%), while also greatly enhancing flexibility and stability, making it suitable for flexible electronics applications.
[0038] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.
Claims
1. A high-performance dendritic silver-carbon-based composite material, characterized in that: The raw materials of the composite material include dendritic silver powder and carbon-based materials, wherein the mass ratio of dendritic silver to carbon-based materials is 0.2-0.7:1, and the particle size of the dendritic silver powder is 1-10 μm.
2. The high-performance dendritic silver and carbon-based composite material according to claim 1, characterized in that: The mass ratio of dendritic silver to carbon-based materials is 0.5-0.7:
1.
3. The high-performance dendritic silver and carbon-based composite material according to claim 1, characterized in that: The dendritic silver powder has a purity of 99.9% or higher.
4. The high-performance dendritic silver and carbon-based composite material according to claim 1, characterized in that: The carbon-based material is at least one of graphene or carbon nanotubes.
5. The high-performance dendritic silver and carbon-based composite material according to claim 4, characterized in that: The graphene has a thickness of less than 1 nm, an area of more than 100 μm², and a purity of over 98%. The carbon nanotubes have a diameter of 1-5 nm, a length greater than 5 μm, and a purity of over 90%.
6. The high-performance dendritic silver and carbon-based composite material according to claim 1, characterized in that: The composite material has a maximum electrical conductivity of 1.2 × 10⁻⁶. 5 The shielding performance has the following properties: S / cm, thermal conductivity exceeding 1400 W / mK, electromagnetic shielding effectiveness greater than 40 dB, bending radius less than 5 mm, and relative dispersion stability greater than 0.
95.
7. A method for preparing a high-performance dendritic silver and carbon-based composite material according to any one of claims 1-6, characterized in that: Includes the following steps: a. Mix dendritic silver powder and carbon-based materials in an ethanol solution at a ratio of 0.5-0.7:1; b. Use an ultrasonic disperser at a power of 150~250 W and a frequency of 30~70 kHz for 5~60 minutes to disperse the particles; c. Apply the mixed solution to the substrate surface using a spin coater and dry it in a vacuum environment at a temperature of 60~120℃ for 0.5~1.5 hours; d. Perform heat treatment in a vacuum heat treatment furnace at a temperature of 120~170℃ for 1~3 hours.
8. The method for preparing a high-performance dendritic silver and carbon-based composite material according to claim 7, characterized in that: The specific steps are as follows: a. Mix dendritic silver powder and carbon-based materials in an ethanol solution at a ratio of 0.5-0.7:1; b. Dispersion was performed using an ultrasonic disperser at a power of 200 W and a frequency of 40 kHz for 30 minutes; c. Apply the mixed solution to the substrate surface using a spin coater and dry it in a vacuum environment at 80°C for 1 hour. d. Perform heat treatment in a vacuum heat treatment furnace at a temperature of 150°C for 2 hours.
9. The application of a high-performance dendritic silver and carbon-based composite material according to any one of claims 1-5 in flexible electronic devices, electromagnetic shielding devices, or high thermal conductivity heat sinks.
10. The application according to claim 9, wherein the composite material achieves a shielding effectiveness greater than 40 dB in electromagnetic shielding.