Super capacitor electrode material

Abstract

The invention relates to the technical field of new energy materials, and discloses a supercapacitor electrode material which comprises the following components in parts by mass: 35-45 parts of a carbon material; 8-12 parts of a metal oxide; 15-25 parts of a conductive polymer; 2-6 parts of a binder; 13-22 parts of a conductive additive; 0.2 to 0.6 part of a surfactant; 0.05 to 0.1 part of a dopant; the preparation method comprises the following steps: pretreating the materials, mixing and stirring under set conditions to obtain mixed slurry, coating the surface of an electrode substrate with the mixed slurry, and carrying out curing treatment to obtain a final electrode. The graphene sheets and the molybdenum disulfide cooperatively work in the material-filler to form a heterojunction structure, so that the conductivity and the ion transmission performance of the electrode material are improved, and the performance of the electrode material is improved. And the specific capacitance, the energy density, the power density and the cycling stability of the supercapacitor electrode material are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy materials, in particular to supercapacitor electrode materials. Background Art

[0002] With the rapid development of new energy technologies, supercapacitors, as highly efficient and fast-charging and discharging energy storage devices, have attracted widespread attention. The performance of supercapacitors primarily depends on the electrochemical properties of their electrode materials, including specific capacitance, energy density, power density, and cycling stability. Traditional electrode materials, such as single carbon materials or metal oxides, while exhibiting promising performance in some areas, still have deficiencies in overall performance, making it difficult to meet the demands of high-performance supercapacitors.

[0003] In recent years, researchers have tried to further improve the performance of electrode materials by introducing composite structures of multiple materials. For example, metal oxides (such as manganese dioxide, aluminum oxide, cobalt oxide, and ruthenium oxide) are widely used in electrode materials due to their excellent catalytic properties and electrochemical activity. However, single metal oxides often have the problem of insufficient conductivity, which limits their performance in high power density applications. In addition, conductive polymers (such as polythiophene and polypyrrole) are also used to improve the performance of electrode materials due to their good conductivity and chemical stability, but they still face the challenges of poor dispersibility and insufficient mechanical stability in practical applications.

[0004] The present invention aims to comprehensively improve the comprehensive performance of supercapacitor electrode materials by optimizing the formula and preparation process of electrode materials, introducing ruthenium oxide, conductive polymers and molybdenum disulfide, and forming a heterojunction structure through graphene sheets and molybdenum disulfide, so as to achieve excellent performance in specific capacitance, energy density, power density and cycle stability, thereby meeting the needs of high-performance supercapacitors. Summary of the Invention

[0005] (1) Technical problems solved

[0006] In response to the shortcomings of the existing technology, the present invention provides a supercapacitor electrode material with the advantages of high specific capacitance, high energy density, high power density and excellent cycle stability, which solves the problem that the comprehensive performance of existing electrode materials is insufficient and it is difficult to simultaneously meet the needs of high-performance supercapacitors.

[0007] (2) Technical solution

[0008] To achieve the above-mentioned object, the present invention provides the following technical solution: a supercapacitor electrode material, wherein the electrode material and its mass parts include: 35-45 parts of carbon material; 8-12 parts of metal oxide; 15-25 parts of conductive polymer; 2-6 parts of binder; 13-22 parts of conductive additive; 0.2-0.6 parts of surfactant; 0.05-0.1 parts of dopant; and 14-20 parts of filler.

[0009] Preferably, the electrode material and its mass parts include: 38 parts of carbon material; 10 parts of metal oxide; 19 parts of conductive polymer; 5 parts of binder; 16 parts of conductive additive; 0.35 parts of surfactant; 0.09 parts of dopant; and 14 parts of filler.

[0010] Preferably, the carbon material consists of carbon fiber and graphite fiber in a ratio of 4:1, and the metal oxide consists of manganese dioxide, aluminum oxide, cobalt oxide and ruthenium oxide in a ratio of 3:3:1:1.

[0011] Preferably, the conductive polymer is composed of polythiophene and polypyrrole in a ratio of 5:6, and the binder is composed of one of polyvinylidene fluoride and polytetrafluoroethylene.

[0012] Preferably, the conductive additive is composed of carbon black and carbon nanotubes in a ratio of 4:3, and the surfactant is composed of sodium dodecylbenzenesulfonate.

[0013] Preferably, the dopant consists of p-toluenesulfonic acid, and the filler consists of 3:1 graphene sheets and molybdenum disulfide.

[0014] Preferably, the supercapacitor electrode material comprises the following steps:

[0015] Step 1: Raw material preparation: prepare the raw material formula ratio of carbon material, metal oxide, conductive polymer, binder, conductive additive, surfactant, dopant and filler;

[0016] Step 2: Pretreatment of raw materials: pretreatment of carbon materials, metal oxides, conductive additives and fillers respectively;

[0017] Step 3: Mixing and slurrying: adding the pretreated carbon material, metal oxide, conductive additive and filler to the dopant, preliminarily mixing them evenly, and then adding the conductive polymer, binder and surfactant to obtain a mixed slurry;

[0018] Step 4: Surface treatment: Coat the mixed slurry on the surface of the electrode substrate and dry it in a vacuum oven at a temperature of 75-80°C for 1.5-2.5 hours to obtain the electrode. Then, use a plasma treatment device to modify the electrode surface at a treatment power of 100-150W and a treatment time of 5-10 minutes.

[0019] Step 5: Molding and curing: The surface-treated electrode is pressed into shape at a pressure of 10-15 MPa, and then transferred to a high-temperature furnace and cured at a temperature of 150-180°C for 1-1.5 hours.

[0020] Preferably, in step 2, the raw materials are pretreated by grinding the carbon material, metal oxide, conductive additive and filler separately so that the particle size of the carbon material reaches the range of 50-100 nanometers, the particle size of the metal oxide reaches the range of 30-50 nanometers, the conductive additive reaches the range of 40-80 nanometers, and the particle size of the filler reaches the range of 10-30 nanometers.

[0021] Preferably, the mixing and pulping process in step 3:

[0022] S3.1. Add the pretreated carbon material, conductive additive, and filler to the dopant and stir at a speed of 1200-1500 rpm for 1.2-1.5 hours.

[0023] S3.2. Add the conductive polymer and continue stirring for 50-60 minutes;

[0024] S3.3. Add binder and surfactant, and stir at a speed of 400-500 r / min for 30-45 minutes to form a mixed slurry.

[0025] Preferably, the graphene sheet and molybdenum disulfide are formed into a heterojunction structure by chemical vapor deposition, and the obtained reaction formula is:

[0026] GNP+MoS2→GNPMoS2 heterojunction

[0027] In the reaction formula, graphene nanosheets and molybdenum disulfide are formed under high temperature conditions, and gases containing carbon source and molybdenum source are introduced into the reaction chamber. Through chemical reactions, graphene nanosheets and molybdenum disulfide are deposited on the substrate to form a heterojunction structure with a synergistic effect.

[0028] Compared with the prior art, the present invention provides a supercapacitor electrode material with the following beneficial effects:

[0029] 1. The present invention introduces manganese dioxide, aluminum oxide, cobalt oxide and ruthenium oxide into metal oxides. Since manganese dioxide has a high theoretical specific capacitance and abundant redox reaction sites, aluminum oxide has good chemical stability and electrochemical inertness, and can inhibit the volume expansion and structural collapse of other active materials, cobalt oxide has high electrochemical activity and catalytic performance, and can accelerate the electrode reaction. Ruthenium oxide has excellent electrochemical activity and a wide voltage window, and can improve the specific capacitance and energy density of the electrode material. The four metal oxides work together to jointly enhance the electrochemical activity and wide voltage window of the electrode material. By adding graphene sheets and molybdenum disulfide to the filler, since the graphene sheets have excellent conductivity and a large specific surface area, and molybdenum disulfide has good conductivity and ion transport performance, they work together to form a heterojunction structure, which ultimately effectively improves the specific capacitance, energy density, power density and cycle stability of the supercapacitor electrode material. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A flow chart was prepared for the present invention. DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] See also Figure 1 A supercapacitor electrode material, the electrode material and its mass parts include: 35-45 parts of carbon material; 8-12 parts of metal oxide; 15-25 parts of conductive polymer; 2-6 parts of binder; 13-22 parts of conductive additive; 0.2-0.6 parts of surfactant; 0.05-0.1 parts of dopant; and 14-20 parts of filler.

[0033] Specifically, the carbon material is composed of 4:1 carbon fiber and graphite fiber, which provides conductivity and enhances the mechanical properties of the material. Among them, carbon fiber has high strength, high modulus and excellent conductivity, and can provide stable mechanical properties and fast electron conduction channels for electrode materials, while graphite fiber has good conductivity and a large specific surface area, which helps to improve the overall conductivity and electrochemical activity of the electrode material. The synergistic effect of the two not only enhances the mechanical properties of the electrode material, making it less likely to break or deform during preparation and use, but also provides more paths for the rapid transmission of electrons, thereby effectively improving the electrochemical properties of the electrode material. The metal oxide is composed of manganese dioxide, aluminum oxide, cobalt oxide and ruthenium oxide in a ratio of 3:3:1:1, and is used for catalysis and electrochemical reactions. Among them, manganese dioxide has a high theoretical specific capacitance and good electrochemical stability, and can provide rich redox reaction sites, thereby improving the specific capacitance of the electrode material. Aluminum oxide has good chemical stability and electrochemical inertness, and can effectively inhibit the volume expansion and structural collapse of other active materials during the charge and discharge process, thereby improving the cycle stability of the electrode material. Cobalt oxide has high electrochemical activity and good catalytic performance, which can accelerate the electrode reaction and improve the charge and discharge efficiency of the electrode material. Ruthenium oxide has excellent electrochemical activity and a wide voltage window, which can improve the specific capacitance and energy density of the electrode material. In addition, ruthenium oxide can also synergize with aluminum oxide to inhibit the phase change of cobalt oxide during the charge and discharge process, thereby further improving the cycle stability of the electrode material.

[0034] Specifically, the conductive polymer is composed of polythiophene (PT) and polypyrrole (PPy) in a ratio of 5:6. Both polythiophene (PT) and polypyrrole (PPy) are chemically synthesized and have good conductivity and chemical stability. They are doped with dopants to further improve the conductivity. Among them, polythiophene (PT) has high conductivity and good electrochemical stability, and can form a continuous conductive network in the electrode material, thereby improving the conductivity of the electrode material. Polypyrrole (PPy) has good electrochemical activity and volume buffering capacity, and can effectively buffer the volume change of the active substance during the charge and discharge process, thereby improving the cycle stability of the electrode material. The synergistic effect of the two can not only improve the conductivity of the electrode material, but also enhance the electrode material during the charge and discharge process. Structural stability. The binder is composed of 1:1 polyvinylidene fluoride (PVDF) or polytetrafluoroethylene (PTFE), which is used to bond the various components of the material together to improve the integrity of the material. Among them, polyvinylidene fluoride (PVDF) has good mechanical properties and chemical stability, and can form a tough bonding network in the electrode material, tightly bonding the carbon material, metal oxide, conductive polymer and other components together, thereby improving the integrity of the electrode material. Polytetrafluoroethylene (PTFE) has excellent chemical stability and thermal stability, and can remain stable in high temperature and strong electrolyte environments, further enhancing the structural stability of the electrode material. The synergistic effect of the two can not only improve the integrity of the electrode material, but also enhance the adaptability of the electrode material under different environmental conditions.

[0035] Specifically, the conductive additive is composed of carbon black and carbon nanotubes in a ratio of 4:3, which further improves the conductivity of the material and improves the electrical properties. The surfactant is composed of sodium dodecylbenzenesulfonate (SDBS), which improves the dispersibility of the material and helps to evenly mix the components during the preparation process.

[0036] Specifically, the dopant is composed of p-toluenesulfonic acid (PTSA, used for polymer doping), which is used for doping conductive polymers to improve their conductivity. The filler is composed of 3:1 graphene sheets and molybdenum disulfide, which increases the ion diffusion rate and improves the electrochemical properties of the material.

[0037] Specifically, the supercapacitor electrode material includes the following steps:

[0038] Step 1: Raw material preparation: prepare carbon materials, metal oxides, conductive polymers, binders, conductive additives, surfactants, dopants and fillers in specific raw material formula ratios;

[0039] Step 2: Pretreatment of raw materials: pretreatment of carbon materials, metal oxides, conductive additives and fillers respectively;

[0040] Step 3: Mixing and slurrying: adding the pretreated carbon material, metal oxide, conductive additive and filler to the dopant, preliminarily mixing them evenly, and then adding the conductive polymer, binder and surfactant to obtain a mixed slurry;

[0041] Step 4: Surface treatment: The mixed slurry is evenly coated on the surface of the electrode substrate, dried in a vacuum oven at a temperature of 75-80°C for 1.5-2.5 hours, and the electrode surface is modified using a plasma treatment device with a treatment power of 100-150W and a treatment time of 5-10 minutes to improve the hydrophilicity and activity of the electrode surface and enhance the interaction with the electrolyte;

[0042] Step 5: Molding and curing: The surface-treated electrode is pressed into shape under a pressure of 10-15 MPa, then transferred to a high-temperature furnace and cured at a temperature of 150-180°C for 1-1.5 hours to obtain the electrode, so that the binder can fully play its role, enhance the bonding force between the components of the electrode material, and improve the mechanical strength and stability of the electrode.

[0043] Specifically, in step 2, the raw materials are pretreated by grinding the carbon material, metal oxide, conductive additive and filler separately to increase the specific surface area and improve the activity.

[0044] Specifically, the mixing and pulping process in step 3:

[0045] S3.1. Add the pretreated carbon material, conductive additive, and filler to the dopant and stir at a speed of 1200-1500 rpm for 1.2-1.5 hours to achieve preliminary mixing.

[0046] S3.2. Add the conductive polymer and continue stirring for 50-60 minutes to ensure that the conductive polymer is evenly dispersed in the system;

[0047] S3.3. Add binder and surfactant, and stir at a speed of 400-500 r / min for 30-45 minutes to form a uniform and stable mixed slurry.

[0048] Specifically, graphene sheets and molybdenum disulfide are deposited by chemical vapor deposition to form a heterojunction structure, and the reaction formula is:

[0049] GNP+MoS2→GNPMoS2 heterojunction

[0050] In the reaction formula, graphene nanosheets and molybdenum disulfide are deposited on the substrate through chemical reactions. A heterojunction structure with a synergistic effect is formed, which helps to improve the conductivity and ion transport properties of the material, thereby improving the performance of the supercapacitor.

[0051] Example 1

[0052] The electrode materials and their weight parts include: 38 parts of carbon material; 10 parts of metal oxide; 19 parts of conductive polymer; 5 parts of binder; 16 parts of conductive additive; 0.35 parts of surfactant; 0.09 parts of dopant; and 14 parts of filler.

[0053] Example 2

[0054] The electrode materials and their weight parts include: 40 parts of carbon material; 8 parts of metal oxide; 25 parts of conductive polymer; 2 parts of binder; 22 parts of conductive additive; 0.6 parts of surfactant; 0.05 parts of dopant; and 20 parts of filler.

[0055] Example 3

[0056] The electrode materials and their weight parts include: 35 parts of carbon material; 12 parts of metal oxide; 15 parts of conductive polymer; 4 parts of binder; 13 parts of conductive additive; 0.2 parts of surfactant; 0.1 parts of dopant; and 14 parts of filler.

[0057] Comparative Example 1

[0058] The ruthenium oxide in the metal oxide in Example 1 was deleted, and the other raw materials remained unchanged.

[0059] Comparative Example 2

[0060] The conductive polymer in Example 2 was deleted, and the other raw materials remained unchanged.

[0061] Comparative Example 3

[0062] The molybdenum disulfide in the filler of Example 3 was replaced with molybdenum diselenide.

[0063] The above embodiments and comparative examples were made into electrode materials, and the test data of the electrode materials of embodiments 1, 2, and 3 were compared. The test data of the electrode materials of embodiment 1 and comparative example 1, embodiment 2 and comparative example 2, and embodiment 3 and comparative example 3 were compared respectively. The specific data are shown in Table 1 below:

[0064] Table 1

[0065]

[0066] The following information can be obtained from Table 1: In Example 1, the ratio of metal oxide (including ruthenium oxide) and conductive polymer (19 parts) is balanced, and the synergistic catalysis and conductivity are optimal. In Example 2, the ratio of conductive polymer is high, but the ratio of conductive additive is also high, resulting in a decrease in porosity and obstruction of ion transport. In Example 3, the ratio of metal oxide is high, but the ratio of conductive polymer is low, and the overall performance is slightly inferior to that of Example 1. In Example 1, ruthenium oxide improves redox activity, and the filler (GNP molybdenum disulfide) optimizes ion diffusion. The lower energy density of Example 2 is because the ratio of conductive additive is too high, which affects the overall energy storage capacity. The energy density of Example 3 is The power density is slightly lower, but close to that of Example 1, showing better performance; the power density in Example 1 is the highest, indicating that its ion transmission and electron conduction performance are optimal, while the proportion of the conductive additive in Example 2 is too high, resulting in a decrease in porosity, obstructed ion transmission, and a lower power density. The power density in Example 3 is close to that of Example 1, showing better dynamic performance. The cyclic stability of Example 1 is the highest, so its material structure and chemical stability are optimal; the cyclic stability of Example 2 is slightly lower because the proportion of the conductive additive is too high, which affects the structural stability of the material. The cyclic stability of Example 3 is close to that of Example 1, showing better durability.

[0067] Comparison Table 2 of Example 1 and Comparative Example 1

[0068]

[0069] Comparison Table 3 of Example 2 and Comparative Example 2

[0070]

[0071]

[0072] Comparison Table 4 of Example 3 and Comparative Example 3

[0073]

[0074]

[0075] Summary: The above table data and analysis verify that the electrode material formula and preparation process of the embodiments of the present invention are better than those of the comparative examples. Among Examples 1-3, Example 1 shows the best comprehensive performance. The present invention improves the electrochemical activity and wide voltage window of the electrode material by introducing ruthenium oxide, conductive polymer and molybdenum disulfide into the metal oxide. By adding graphene sheets and molybdenum disulfide to the filler, they work together to form a heterojunction structure, thereby improving the conductivity and ion transport performance of the electrode material, and ultimately improving the specific capacitance, energy density, power density and cycle stability of the supercapacitor electrode material.

[0076] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A supercapacitor electrode material, characterized in that: The electrode materials and their weight parts include: 35-45 parts of carbon material; 8-12 parts of metal oxide; 15-25 parts of conductive polymer; 2-6 parts of binder; 13-22 parts of conductive additive; 0.2-0.6 parts of surfactant; 0.05-0.1 parts of dopant; and 14-20 parts of filler.

2. The supercapacitor electrode material according to claim 1, wherein: The electrode materials and their weight parts include: 38 parts of carbon material; 10 parts of metal oxide; 19 parts of conductive polymer; 5 parts of binder; 16 parts of conductive additive; 0.35 parts of surfactant; 0.09 parts of dopant; and 14 parts of filler.

3. The supercapacitor electrode material according to claim 1, wherein: The carbon material consists of carbon fiber and graphite fiber in a ratio of 4:1, and the metal oxide consists of manganese dioxide, aluminum oxide, cobalt oxide and ruthenium oxide in a ratio of 3:3:1:

1.

4. The supercapacitor electrode material according to claim 1, wherein: The conductive polymer is composed of polythiophene and polypyrrole in a ratio of 5:6, and the binder is composed of polyvinylidene fluoride or polytetrafluoroethylene.

5. The supercapacitor electrode material according to claim 1, wherein: The conductive additive consists of carbon black and carbon nanotubes in a ratio of 4:3, and the surfactant consists of sodium dodecylbenzenesulfonate.

6. The supercapacitor electrode material according to claim 1, wherein: The dopant consists of p-toluenesulfonic acid, and the filler consists of 3:1 graphene sheets and molybdenum disulfide.

7. The supercapacitor electrode material according to claim 1, characterized in that The following steps are involved: Step 1: Raw material preparation: prepare the raw material formula ratio of carbon material, metal oxide, conductive polymer, binder, conductive additive, surfactant, dopant and filler; Step 2: Pretreatment of raw materials: pretreatment of carbon materials, metal oxides, conductive additives and fillers respectively; Step 3: Mixing and slurrying: adding the pretreated carbon material, metal oxide, conductive additive and filler to the dopant, preliminarily mixing them evenly, and then adding the conductive polymer, binder and surfactant to obtain a mixed slurry; Step 4: Surface treatment: Coat the mixed slurry on the surface of the electrode substrate and dry it in a vacuum oven at a temperature of 75-80°C for 1.5-2.5 hours to obtain the electrode. Then, use a plasma treatment device to modify the electrode surface at a treatment power of 100-150W and a treatment time of 5-10 minutes. Step 5: Molding and curing: The surface-treated electrode is pressed into shape at a pressure of 10-15 MPa, and then transferred to a high-temperature furnace and cured at a temperature of 150-180°C for 1-1.5 hours.

8. The supercapacitor electrode material according to claim 7, wherein: The raw material pretreatment in step 2 is as follows: the carbon material, metal oxide, conductive additive and filler are ground separately to make the particle size of the carbon material reach the range of 50-100 nanometers, the particle size of the metal oxide reach the range of 30-50 nanometers, the conductive additive reach the range of 40-80 nanometers, and the particle size of the filler reach the range of 10-30 nanometers.

9. The supercapacitor electrode material according to claim 7, wherein: The mixing and pulping process in step 3: S3.

1. Add the pretreated carbon material, conductive additive, and filler to the dopant and stir at a speed of 1200-1500 rpm for 1.2-1.5 hours. S3.

2. Add the conductive polymer and continue stirring for 50-60 minutes; S3.

3. Add binder and surfactant, and stir at a speed of 400-500 r / min for 30-45 minutes to form a mixed slurry.

10. The supercapacitor electrode material according to claim 7, characterized in that The graphene sheet and molybdenum disulfide are formed into a heterojunction structure by chemical vapor deposition, and the reaction formula is: GNP+MoS2→GNPMoS2 heterojunction In the reaction formula, graphene nanosheets and molybdenum disulfide are formed under high temperature conditions, and gases containing carbon source and molybdenum source are introduced into the reaction chamber. Through chemical reactions, graphene nanosheets and molybdenum disulfide are deposited on the substrate to form a heterojunction structure with a synergistic effect.

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