Positive electrode material for improving rate capability of supercapacitor and preparation method of positive electrode material
By doping gadolinium into α-MnO2 and compounding it with Ti3C2Tx to form α-MnO2@Gd/Ti3C2Tx material, the problem of insufficient rate performance of α-MnO2 positive electrode material was solved, and the charge and discharge efficiency of supercapacitors was significantly improved.
Patent Information
- Application Number
- CN202510985561.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-17
- Publication Date
- 2025-09-12
AI Technical Summary
How to improve the rate performance of α-MnO2 as a supercapacitor cathode material.
A two-step hydrothermal synthesis method was used to first dope gadolinium (Gd) into α-MnO2 and then composite it with Ti3C2Tx to form α-MnO2@Gd/Ti3C2Tx material, which enhanced the specific surface area and electronic conductivity of the material.
By enhancing the specific surface area and electronic conductivity of the material, the ion transport performance of the supercapacitor during the charge and discharge process is improved, and the rate performance is improved.
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Figure CN120637124A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of electronic components, and in particular to a positive electrode material for improving the rate performance of a supercapacitor and a preparation method thereof. Background Art
[0002] With the development of society, the demand for supercapacitors is increasing, and research on different types of supercapacitor positive and negative active materials is also very important.
[0003] Manganese dioxide (MnO2) has made significant progress in the past few years due to its non-toxicity and high theoretical capacity. Depending on its crystalline phase, MnO2 can be classified as δ-MnO2, α-MnO2, and amorphous MnO2. Currently, research on α-MnO2 as a supercapacitor cathode material is intensive, but improving its rate performance remains a thorny issue. Summary of the Invention
[0004] The object of the present invention is to provide a positive electrode material and a preparation method thereof for improving the rate performance of a supercapacitor, so as to solve the problems raised in the prior art.
[0005] To achieve the above object, the present invention provides the following technical solutions: A method for preparing a positive electrode material for improving the rate performance of a supercapacitor comprises the following steps: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly and then conduct a hydrothermal reaction. After the reaction, wash them alternately with alcohol and water and then vacuum dry them to obtain α-MnO2@Gd; Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, a hydrothermal reaction was carried out. After the reaction was completed, the mixture was washed alternately with alcohol and water and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , i.e. the positive electrode material; Preferably, in step 1, the mass ratio of α-MnO2 to gadolinium nitrate hexahydrate is (40-65):1; Preferably, the temperature of the hydrothermal reaction in step 1 is 160-180° C., and the reaction time is 10-12 h; Preferably, in step 2, α-MnO2 and Ti3C2T x The mass ratio is (11-21):1; Preferably, the temperature of the hydrothermal reaction in step 2 is 120-160° C., and the reaction time is 10-16 h; The positive electrode material prepared by the above preparation method can be used in supercapacitors; Preferably, the supercapacitor includes an active electrode material; the preparation steps of the active electrode material are: mixing the positive electrode material, the binder, the conductive agent and the solvent to obtain an active slurry, coating the slurry on carbon paper and vacuum drying the slurry; Preferably, the mass ratio of the positive electrode material, the binder and the conductive agent is (80-90):(2-10):(8-10); more preferably 8:1:1; Preferably, the solid content of the active slurry is 50-52%; Preferably, the surface density of the active slurry after coating and drying is 10-15 g / m 2 ; Preferably, the vacuum drying temperature is 60-80°C and the time is 20-24h; Compared with the prior art, the present invention has the following beneficial effects: The present invention adopts a two-step hydrothermal synthesis method to synthesize α-MnO2@Gd / Ti3C2T x Material: Through the first step of hydrothermal synthesis, gadolinium is doped, and the appropriate amount of Gd doping will lead to crystal defects in α-MnO2, thereby increasing the specific surface area of the material and enhancing the kinetic reversibility, which is beneficial to the transport of ions during the charge and discharge process of the supercapacitor, thereby improving the rate performance; Through the second step of hydrothermal synthesis, α-MnO2@Gd was grown on the layered MXene (Ti3C2T x ), the electronic conductivity of the composite material is enhanced through the structure formed by close bonding. At the same time, the large specific surface area of MXene materials also increases more active sites, improves the kinetic behavior of ions, and greatly improves the rate performance. BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Figure 1 α-MnO2@Gd / Ti3C2T prepared by the present invention x Scanning electron microscope image of the material. DETAILED DESCRIPTION
[0007] 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.
[0008] The α-MnO2 model in the experiment was TMXC-003, purchased from Tongmanganese New Materials; Ti3C2T xThe multilayer nanosheets have a sheet diameter of 2-10 μm and were purchased from Xianfeng Nano. The binder is polyvinylidene fluoride, model KF W7200, purchased from Kureha, Japan. The conductive agent is Super P, brand TMEGO, Switzerland. The carbon paper is 0.19 mm thick and model TGP-H-060, purchased from Toray, Japan. Example 1: This example provides a method for preparing a positive electrode material and applying it in an active electrode material. The specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven for 12 hours at 160°C for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol, and then vacuum dry them to obtain α-MnO2@Gd. Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , i.e. positive electrode material; Step 3: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was then coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 That is, active electrode materials; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 53:1, and the mass ratio of α-MnO2 to Ti3C2T x The mass ratio is 16:1.
[0009] Example 2: basically the same as Example 1, except that the mass ratio of α-MnO2 to Gd(NO3)3.6H2O is 43:1; the specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven for 12 hours at 160°C for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol, and then vacuum dry them to obtain α-MnO2@Gd. Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x, i.e. positive electrode material; Step 3: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 43:1, and the mass ratio of α-MnO2 to Ti3C2T x The mass ratio is 16:1.
[0010] Example 3: basically the same as Example 1, except that the mass ratio of α-MnO2 to Gd(NO3)3.6H2O is 48:1; the specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven for 12 hours at 160°C for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol, and then vacuum dry them to obtain α-MnO2@Gd. Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , i.e. positive electrode material; Step 3: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 48:1, and the mass ratio of α-MnO2 to Ti3C2T x The mass ratio is 16:1.
[0011] Example 4: basically the same as Example 1, except that the mass ratio of α-MnO2 to Gd(NO3)3.6H2O is 58:1; the specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven for 12 hours at 160°C for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol, and then vacuum dry them to obtain α-MnO2@Gd. Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , i.e. positive electrode material; Step 3: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 58:1, and the mass ratio of α-MnO2 to Ti3C2T x The mass ratio is 16:1.
[0012] Example 5: basically the same as Example 1, except that the mass ratio of α-MnO2 to Gd(NO3)3.6H2O is 63:1; the specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven for 12 hours at 160°C for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol, and then vacuum dry them to obtain α-MnO2@Gd. Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , i.e. positive electrode material; Step 3: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 63:1, and the mass ratio of α-MnO2 to Ti3C2T x The mass ratio is 16:1.
[0013] Example 6: basically the same as Example 1, except that: α-MnO2 and Ti3C2T x The mass ratio is 12:1; the specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven for 12 hours at 160°C for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol, and then vacuum dry them to obtain α-MnO2@Gd. Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , i.e. positive electrode material; Step 3: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 53:1, and the mass ratio of α-MnO2 to Ti3C2T x The mass ratio is 12:1.
[0014] Example 7: basically the same as Example 1, except that: α-MnO2 and Ti3C2T x The mass ratio is 14:1; the specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven for 12 hours at 160°C for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol, and then vacuum dry them to obtain α-MnO2@Gd. Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , i.e. positive electrode material; Step 3: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 53:1, and the mass ratio of α-MnO2 to Ti3C2T x The mass ratio is 14:1.
[0015] Example 8: basically the same as Example 1, except that: α-MnO2 and Ti3C2T x The mass ratio is 18:1; the specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven for 12 hours at 160°C for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol, and then vacuum dry them to obtain α-MnO2@Gd. Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , i.e. positive electrode material; Step 3: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 53:1, and the mass ratio of α-MnO2 to Ti3C2T x The mass ratio is 18:1.
[0016] Example 9: basically the same as Example 1, except that: α-MnO2 and Ti3C2T x The mass ratio is 20:1; the specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven for 12 hours at 160°C for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol, and then vacuum dry them to obtain α-MnO2@Gd. Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , i.e. positive electrode material; Step 3: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 53:1, and the mass ratio of α-MnO2 to Ti3C2T x The mass ratio is 20:1.
[0017] Comparative Example 1: As a control experiment of Example 1, Gd doping was not performed, and the specific steps were as follows: Step 1: Mix α-MnO2 with Ti3C2T x After being mixed evenly in deionized water, the mixture was transferred to a reactor and placed in a blast drying oven for baking at 140 ° C for 12 h for hydrothermal reaction. After the reaction, the mixture was washed with deionized water and alcohol and then vacuum dried to obtain α-MnO2 / Ti3C2T x , i.e. positive electrode material; Step 2: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; Among them, α-MnO2 and Ti3C2T x The mass ratio is 16:1.
[0018] Comparative Example 2: As a control experiment of Example 1, Ti3C2T x , the specific steps are as follows: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly, transfer them to a reactor, and place them in a forced air drying oven and bake them at 160°C for 12 hours for hydrothermal reaction. After the reaction, wash them with deionized water and alcohol and then vacuum dry them to obtain α-MnO2@Gd, the positive electrode material; Step 2: The positive electrode material, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; The mass ratio of α-MnO2 to Gd(NO3)3·6H2O is 53:1.
[0019] Comparative Example 3: As a control experiment of Example 1, α-MnO2 is used as the positive electrode material, and the specific steps are as follows: α-MnO2, binder and conductive agent were stirred and mixed in a mass ratio of 8:1:1, and N-methylpyrrolidone was added and mixed evenly to obtain an active slurry with a solid content of 51%. The slurry was coated on carbon paper and placed in a vacuum drying oven. After drying at 60°C for 24 hours, the surface density of the active material on the carbon paper was 12 g / m 2 , i.e., active electrode material; Detection test: GCD (constant current charge and discharge) tests were performed using a three-electrode test system and an electrochemical workstation. A 0.5 M Na2SO4 solution was used as the electrolyte in the electrolytic cell, an Ag / AgCl electrode was used as the reference electrode, a Pt electrode was used as the counter electrode, and the active electrode materials prepared in Examples 1-9 and Comparative Examples 1-3 were used as the working electrode. The operating voltage range was 0 V to 1.0 V. Current densities of 1 A / g, 5 A / g, and 10 A / g were applied in sequence. The capacitance was measured, and the percentage of the ratio of the capacitance value measured at a current density of 10 A / g to the capacitance value measured at 1 A / g was used as the capacitance retention rate. The data are recorded in the table below.
[0020]
[0021] From the above data, it can be seen that the introduction of Gd and MXene into α-MnO2 is beneficial to the transport of ions during the charge and discharge process, thereby improving the rate performance; the α-MnO2@Gd / Ti3C2T prepared by the present invention x As an electrode material, it can effectively improve the rate performance of supercapacitors.
[0022] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.
Claims
1. A method for preparing a positive electrode material for improving the rate performance of a supercapacitor, characterized in that: The method comprises the following preparation steps: Step 1: Add α-MnO2 and gadolinium nitrate hexahydrate to deionized water, mix them evenly and then conduct a hydrothermal reaction. After the reaction, wash them alternately with alcohol and water and then vacuum dry them to obtain α-MnO2@Gd; Step 2: Combine α-MnO2@Gd with Ti3C2T x After being mixed evenly in deionized water, a hydrothermal reaction was carried out. After the reaction was completed, the mixture was washed alternately with alcohol and water and then vacuum dried to obtain α-MnO2@Gd / Ti3C2T x , that is, the positive electrode material.
2. The method for preparing a positive electrode material for improving the rate performance of a supercapacitor according to claim 1, characterized in that: The mass ratio of α-MnO2 and gadolinium nitrate hexahydrate in step 1 is (40-65):
1.
3. The method for preparing a positive electrode material for improving the rate performance of a supercapacitor according to claim 1, characterized in that: The temperature of the hydrothermal reaction in step 1 is 160-180° C., and the reaction time is 10-12 h.
4. The method for preparing a positive electrode material for improving the rate performance of a supercapacitor according to claim 1, characterized in that: In step 2, α-MnO2 and Ti3C2T x The mass ratio is (11-21):
1.
5. The method for preparing a positive electrode material for improving the rate performance of a supercapacitor according to claim 1, characterized in that: The temperature of the hydrothermal reaction in step 2 is 120-160° C., and the reaction time is 10-16 hours.
6. A positive electrode material, characterized in that Prepared by the preparation method according to any one of claims 1 to 5.
7. Use of the positive electrode material according to claim 6 in a supercapacitor, characterized in that: The supercapacitor includes active electrode materials. The preparation steps of the active electrode materials are: stirring the positive electrode material, a binder, a conductive agent and a solvent to obtain an active slurry, coating it on carbon paper and vacuum drying it.
8. Use of the positive electrode material according to claim 7 in a supercapacitor, characterized in that: The mass ratio of the positive electrode material, the binder and the conductive agent is (80-90):(2-10):(8-10); and the solid content of the active slurry is 50-52%.
9. Use of the positive electrode material in a supercapacitor according to claim 7, characterized in that: The surface density of the active slurry after coating and drying is 10-15g / m 2 .
10. Use of the positive electrode material in a supercapacitor according to claim 7, characterized in that: The vacuum drying temperature is 60-80°C and the time is 20-24 hours.