A Mn3O4 material with alkylamine intercalation of different chain lengths and its application as a supercapacitor electrode

Abstract

This invention relates to the field of novel electrode materials, specifically to a Mn3O4 material with alkylamine intercalation of different chain lengths and its application as a supercapacitor electrode. The Mn3O4 material with alkylamine intercalation of different chain lengths is obtained by introducing alkylamines of different chain lengths into MnO2 via a hot intercalation method to expand the interlayer spacing of MnO2, followed by high-temperature calcination under a nitrogen atmosphere. The Mn3O4 material with alkylamine intercalation of different chain lengths prepared by this invention has a large interlayer spacing. When used as a supercapacitor electrode material, it can effectively increase the contact area between the electrode material and the electrolyte, thereby effectively improving the ion diffusion rate during electrode operation and enhancing the electrochemical performance of the manganese oxide material.

Description

Technical Field

[0001] This invention relates to the field of novel electrode materials technology, which can be applied to the field of supercapacitor electrodes. Specifically, it relates to Mn3O4 materials with alkylamine intercalation of different chain lengths and their application as supercapacitor electrode materials. Background Technology

[0002] With the rapid development of science and technology and the economy, human demand for energy is increasing, while fossil resources are limited and cannot meet the needs of rapid industrial development. Therefore, humanity is paying increasing attention to new sustainable energy sources (such as solar and wind power). Energy storage materials play a crucial role in the storage and utilization of new energy sources. In the field of new energy storage, supercapacitors, with their high power density and long cycle life, are the "green" energy storage devices that humanity is pursuing.

[0003] The selection of electrode materials for supercapacitors is crucial to their development. Transition metal oxide electrode materials are among the earliest studied and most mature pseudocapacitive materials. Among numerous transition metal oxides, manganese oxide is considered an ideal electrode material for supercapacitors due to its excellent electrochemical properties and abundant reserves. However, in practical applications, the utilization rate of manganese oxide materials is often low. This is because the interlayer spacing of manganese oxide materials is small, making it difficult for electrolyte ions to penetrate the material's interior, thus reducing the effective contact between the material and the electrolyte. Therefore, developing effective strategies to increase the interlayer spacing and prepare novel manganese oxide materials with large interlayer spacing will greatly promote the practical application of manganese oxide materials in supercapacitors. Summary of the Invention

[0004] The purpose of this invention is to compare the application of Mn3O4 materials with alkylamine intercalation of different chain lengths as electrode materials for supercapacitors. This invention uses Mn3O4 materials with alkylamine intercalation of different chain lengths as electrode materials for supercapacitors to improve the ion diffusion rate during electrode operation, thereby improving the electrochemical performance of the electrode materials.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: a Mn3O4 material with alkylamine intercalation of different chain lengths. The Mn3O4 material with alkylamine intercalation of different chain lengths is obtained by introducing alkylamines of different chain lengths into MnO2 through a hot intercalation method to expand the interlayer spacing of MnO2, and then calcining at high temperature under a nitrogen atmosphere.

[0006] The preparation method of the above-mentioned alkylamine intercalated Mn3O4 material with different chain lengths includes the following steps:

[0007] 1) Dissolve MnO2 and intercalating agent in anhydrous ethanol, place the resulting mixture in a magnetic stirrer for heating and reflux reaction, filter, and vacuum dry to obtain intermediate product;

[0008] 2) The intermediate product obtained in step 1) is calcined at high temperature under a nitrogen atmosphere to change the crystal form and remove the intercalating agent alkylamine to obtain Mn3O4 materials with alkylamine intercalation of different chain lengths.

[0009] In the preparation method described above, in step 1), the intercalating agent is an alkylamine with different chain lengths.

[0010] In the above preparation method, the mass ratio of MnO2 to intercalating agent is 1:0.8-8.5.

[0011] In the above preparation method, step 1), the heating reflux reaction is a heating reflux reaction at 70°C for 96 hours.

[0012] In the preparation method described above, step 2) involves calcining at 650°C for 2 hours.

[0013] The above preparation method uses a heating rate of 2℃ / s.

[0014] The above-mentioned Mn3O4 materials with alkylamine intercalation of different chain lengths are used as electrode materials for supercapacitors.

[0015] The above application is carried out as follows: Mn3O4 materials with alkylamine intercalation of different chain lengths are mixed with polyvinylidene fluoride, superconducting carbon black and N-methylpyrrolidone, and after thorough grinding, they are uniformly coated onto the surface of porous carbon cloth current collector to obtain electrode materials; by mass ratio, Mn3O4 with alkylamine intercalation of different chain lengths: polyvinylidene fluoride: superconducting carbon black = 8:1:1.

[0016] The beneficial effects of the present invention are as follows: The Mn3O4 material with alkylamine intercalation of different chain lengths provided by the present invention has a larger interlayer spacing than the single layered crystal structure material, which can increase the effective contact area between electrolyte ions and the bulk phase of the material and improve the utilization rate of electrode material. Attached Figure Description

[0017] Figure 1 The cyclic voltammetry curves are those of the n-butylamine intercalated Mn3O4 material prepared in Example 1.

[0018] Figure 2 These are the charge-discharge curves of the n-butylamine intercalated Mn3O4 prepared in Example 1 at different current densities.

[0019] Figure 3 The cyclic voltammetry curves are for the dodecylamine-intercalated Mn3O4 material prepared in Example 2.

[0020] Figure 4 These are the charge-discharge curves of the dodecylamine-intercalated Mn3O4 material prepared in Example 2 at different current densities.

[0021] Figure 5 These are XRD images of the alkylamine-intercalated Mn3O4 materials prepared in Examples 1-3.

[0022] Figure 6 The cyclic voltammetry curves are for the hexadecylamine-intercalated Mn3O4 material prepared in Example 3.

[0023] Figure 7 These are the charge-discharge curves of the hexadecylamine-intercalated Mn3O4 material prepared in Example 3 at different current densities. Detailed Implementation

[0024] Example 1

[0025] (I) The preparation method of n-butylamine intercalated Mn3O4 material is as follows:

[0026] 1) Place 0.2g MnO2 and 0.505g n-butylamine in 20mL of anhydrous ethanol and heat under reflux at 70℃ for 96h with a magnetic stirrer. After the reaction is complete, filter and vacuum dry to obtain the intermediate product.

[0027] 2) The intermediate product was transferred to a tube furnace and calcined at 650℃ for 2h under N2 protection to obtain n-butylamine intercalated Mn3O4 material.

[0028] (II) Application

[0029] 1. Preparation of electrode material: 8 mg of n-butylamine intercalated Mn3O4 material was thoroughly ground with 1 mg of polyvinylidene fluoride and 1 mg of superconducting carbon black. 0.05 mL of N-methylpyrrolidone was added, and the mixture was ground again. The resulting slurry was then uniformly coated onto the surface of the porous carbon cloth current collector to obtain the electrode material.

[0030] 2. Electrochemical analysis results:

[0031] Methods: Under ambient temperature and pressure, a porous carbon cloth current collector electrode material coated with n-butylamine-intercalated Mn3O4 was used as the working electrode, a graphite foil as the counter electrode, a saturated calomel electrode as the reference electrode, and 5M LiCl as the electrolyte. Cyclic voltammetry and constant current charge-discharge tests were conducted on the n-butylamine-intercalated Mn3O4 electrode material within a potential range of 0–1 V vs. SCE to study its specific capacity and energy storage rate performance.

[0032] Figure 1 The n-butylamine-intercalated Mn3O4 electrode material prepared in Example 1 was scanned at a rate of 20 mV / s. -1 Cyclic voltammetry, by Figure 1 It can be seen that in 5M LiCl electrolyte, the n-butylamine intercalated Mn3O4 electrode material exhibits a large curve area, indicating that it has excellent energy storage performance.

[0033] Figure 2 The constant current charge-discharge curve of the n-butylamine intercalated Mn3O4 electrode material prepared in Example 1. Figure 2 It can be seen that when the current density is 0.25A g -1 At that time, its specific capacity can reach up to 207mAh g. -1 When the current density increases from 0.25 A / g -1 Increased to 5Ag -1 At that time, its specific capacity was still 128mAh g. -1 This demonstrates superior rate performance.

[0034] Example 2

[0035] (I) The preparation method of dodecylamine-intercalated Mn3O4 material is as follows:

[0036] 1) 0.2 g MnO2 and 1.279 g dodecylamine were placed in 20 mL of anhydrous ethanol and heated under reflux at 70 °C for 96 h with a magnetic stirrer. After the reaction was completed, the mixture was filtered and dried under vacuum to obtain the intermediate product.

[0037] 2) The intermediate product was transferred to a tube furnace and calcined at 650°C for 2 hours under N2 protection to obtain dodecylamine-intercalated Mn3O4 material.

[0038] (II) Application

[0039] 1. Preparation of electrode material: 8 mg of dodecylamine-intercalated Mn3O4 material was thoroughly ground with 1 mg of polyvinylidene fluoride and 1 mg of superconducting carbon black. 0.05 mL of N-methylpyrrolidone was added, and the mixture was ground again. The resulting slurry was then uniformly coated onto the surface of a porous carbon cloth current collector to obtain the electrode material.

[0040] 2. Electrochemical analysis results:

[0041] Methods: Under ambient temperature and pressure, a porous carbon cloth current collector electrode material coated with dodecylamine-intercalated Mn3O4 was used as the working electrode, a graphite foil as the counter electrode, a saturated calomel electrode as the reference electrode, and 5M LiCl as the electrolyte. Cyclic voltammetry and constant current charge-discharge tests were conducted on the dodecylamine-intercalated Mn3O4 electrode material within a potential range of 0–1 V vs. SCE to study its specific capacity and energy storage rate performance.

[0042] Figure 3 The dodecylamine-intercalated Mn3O4 electrode material prepared in Example 2 was scanned at a rate of 20 mV / s.-1 Cyclic voltammetry, by Figure 3 It can be seen that in 5M LiCl electrolyte, the area of ​​the CV curve of the dodecylamine-intercalated Mn3O4 electrode material is larger than that of the n-butylamine-intercalated Mn3O4 electrode material, indicating that the specific capacity of the dodecylamine-intercalated Mn3O4 is greater than that of the n-butylamine-intercalated Mn3O4.

[0043] Figure 4 The constant current charge-discharge curves of the dodecylamine-intercalated Mn3O4 electrode material prepared in Example 2 are shown in the figure. As can be seen from the figure, when the current density is 0.25 A g... -1 At that time, its specific capacity was 229 mAh g. -1 When the current density increases from 0.25 A / g -1 Increased to 5A g -1 At that time, its specific capacity was still 148mAh g. -1 Its specific capacity is higher than that of Mn3O4 intercalated with n-butylamine.

[0044] Example 3

[0045] (I) The preparation method of hexadecylamine-intercalated Mn3O4 material is as follows:

[0046] 1) 0.2 g MnO2 and 1.666 g hexadecylamine were placed in 20 mL of anhydrous ethanol and heated under reflux at 70 °C for 96 h with a magnetic stirrer. After the reaction was completed, the mixture was filtered and dried under vacuum to obtain the intermediate product.

[0047] 2) The intermediate product was transferred to a tube furnace and calcined at 650°C for 2 hours under N2 protection to obtain hexadecylamine-intercalated Mn3O4 material.

[0048] (II) Application

[0049] 1. Preparation of electrode material: 8 mg of hexadecylamine-intercalated Mn3O4 material was thoroughly ground with 1 mg of polyvinylidene fluoride and 1 mg of superconducting carbon black. 0.05 mL of N-methylpyrrolidone was added, and the mixture was ground again. The resulting slurry was then uniformly coated onto the surface of a porous carbon cloth current collector to obtain the electrode material.

[0050] 2. Electrochemical analysis results:

[0051] Methods: Under ambient temperature and pressure, a porous carbon cloth current collector electrode material coated with hexadecylamine-intercalated Mn3O4 was used as the working electrode, a graphite foil as the counter electrode, a saturated calomel electrode as the reference electrode, and 5M LiCl as the electrolyte. Cyclic voltammetry and constant current charge-discharge tests were conducted on the hexadecylamine-intercalated Mn3O4 electrode material within a potential range of 0–1 V vs. SCE to study its specific capacity and energy storage rate performance.

[0052] Figure 5 The XRD patterns are of the alkylamine-intercalated Mn3O4 prepared in Examples 1-3. As shown in the figures, the manganese oxide material after alkylamine intercalation is Mn3O4, corresponding to standard card JCPDS#24-0734.

[0053] Figure 6 The hexadecylamine-intercalated Mn3O4 electrode material prepared in Example 3 was scanned at a rate of 20 mV / s. -1 The cyclic voltammogram, by Figure 6 It can be seen that in 5M LiCl electrolyte, the hexadecylamine-intercalated Mn3O4 electrode material exhibits a curve area much larger than that of dodecylamine-intercalated Mn3O4 and n-butylamine-intercalated Mn3O4.

[0054] Figure 7 The constant current charge-discharge curves of the hexadecylamine-intercalated Mn3O4 electrode material prepared in Example 3 are shown in the figure. As can be seen from the figure, when the current density is 0.25 Ag... -1 At that time, its specific capacitance can reach as high as 272mAh g. -1 When the current density changes from 0.25Ag -1 Increased to 5Ag -1 At that time, its specific capacitance still remained at 196mAh g. -1 It demonstrates the highest specific capacity and energy storage performance.

Claims

1. A Mn3O4 material with alkylamine intercalation of different chain lengths, characterized in that: The Mn3O4 materials with alkylamine intercalation of different chain lengths are obtained by introducing alkylamines with different chain lengths as intercalating agents into MnO2 through a hot intercalation method to expand the interlayer spacing of MnO2, and then calcining them at high temperature under a nitrogen atmosphere. The method for preparing an alkylamine-intercalated Mn3O4 material with different chain lengths includes the following steps: 1) Dissolve MnO2 and intercalating agent in anhydrous ethanol, place the resulting mixture in a magnetic stirrer and heat under reflux at 70 °C for 96 h, filter, and vacuum dry to obtain the intermediate product; 2) The intermediate product obtained in step 1) is heated at a rate of 2 °C / s and calcined at 650 °C for 2 h in a nitrogen atmosphere to change the crystal form and remove the intercalating agent alkylamine to obtain Mn3O4 materials with alkylamine intercalation of different chain lengths. In step 1), the intercalating agent is an alkylamine with different chain lengths; By mass ratio, MnO2:intercalating agent = 1:0.8-8.

5.

2. The application of the alkylamine intercalated Mn3O4 materials with different chain lengths as described in claim 1 as electrode materials for supercapacitors.

3. The application according to claim 2, characterized in that, The method is as follows: Mn3O4 materials with alkylamine intercalation of different chain lengths as described in claim 1 are mixed with polyvinylidene fluoride, superconducting carbon black and N-methylpyrrolidone, and after thorough grinding, they are uniformly coated onto the surface of porous carbon cloth current collector to obtain electrode materials; by mass ratio, Mn3O4 with alkylamine intercalation of different chain lengths: polyvinylidene fluoride: superconducting carbon black = 8:1:1.

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