Preparation method and application of NH < 4 + > intercalated hexagonal prism NMO electrode material growing on carbon cloth in situ
By growing the hexaphrical NMO electrode material with NH4+ intercalation in situ on the carbon cloth, the structural failure problem of existing electrode materials under NH4+ corrosion is solved, and higher ammonium storage and electrochemical performance are achieved.
Patent Information
- Application Number
- CN202411817503.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-11
- Publication Date
- 2025-03-18
AI Technical Summary
The electrode materials of existing ammonium ion supercapacitors are prone to structural damage under the weak acid corrosion of NH4+, which limits their energy density.
Through seed hydrothermal method and preintercalation strategy, the hexaphrological NMO electrode material of NH4+ intercalation layer was grown in situ on the carbon cloth, induced a phase change of the molybdenum trioxide material, and increased the layer spacing to allow the reversible embedding and removal of NH4+.
The ammonium storage performance of molybdenum trioxide as an electrode material is improved, the electrochemical performance is enhanced, the material dissolution is inhibited, and the overall performance of the electrode material is improved.
Smart Images
Figure CN119650313A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of novel electrode materials, and specifically relates to an NH4 + The invention discloses a preparation method of intercalated hexagonal NMO electrode material and its application in aqueous ammonium ion supercapacitors. Background Art
[0002] The global demand for sustainable energy is growing rapidly. In order to concentrate on the use of renewable energy, the research of large-scale energy storage system (ESS) is crucial. Although lithium-ion technology currently occupies most of the market, the limited abundance of lithium in the earth's crust and safety issues related to the flammability of lithium-ion electrolytes limit its application in large-scale energy storage. Supercapacitors have the advantages of high power density, fast charging and discharging speed, long service life, and environmental friendliness. They are widely used in smart grids, hybrid vehicles, portable electronic devices and other fields. NH4 + It is rich in resources, easy to obtain, environmentally friendly, and has a low molar mass (18 g mol -1 ) and fast diffusion speed, so it is considered to be the most promising charge carrier. + The hydrated ionic radius The electrode materials of most ammonium ion supercapacitors (AASCs) are mainly based on transition metal oxides, which can react with NH4 + Form hydrogen bonds and store energy in the form of a double electrical layer, but due to NH4 + The structure of electrode materials is often easily damaged by weak acid corrosion, which limits the energy density of AASCs to a certain extent. Therefore, we prepared an in-situ grown NH4 on carbon cloth by seed hydrothermal method and pre-intercalation strategy. + The intercalated NMO electrode material effectively improves the ammonium storage performance. Summary of the invention
[0003] The present invention aims to provide a NH4 in-situ grown on carbon cloth + Preparation method of intercalated NMO electrode material. The present invention prepares NH4 in situ grown on carbon cloth by seed hydrothermal method and pre-intercalation strategy. + The intercalated NMO electrode material improves the ammonium storage performance of molybdenum trioxide as an electrode material.
[0004] To achieve the above object, the technical solution adopted by the present invention is:
[0005] An in-situ grown NH4 on carbon cloth +The preparation method of the intercalated hexagonal NMO electrode material comprises the following steps:
[0006] 1) Prepare solution: dissolve sodium molybdate in deionized water, stir well, then add concentrated hydrochloric acid, and stir further;
[0007] 2) Seed hydrothermal method: immerse the cleaned carbon cloth in the solution obtained in step 1), blow dry the solution on the surface of the carbon cloth with a hair dryer, and then heat it on a heating plate;
[0008] 3) Prepare precursor solution: add ammonium molybdate and concentrated nitric acid into deionized water and stir evenly, then add ammonium sulfate and stir evenly;
[0009] 4) Hydrothermal reaction: adding the carbon cloth treated in step 2) into the precursor solution for hydrothermal reaction;
[0010] 5) The carbon cloth obtained in step 4) was rinsed with anhydrous ethanol and deionized water for three times respectively, and dried in a vacuum drying oven at 60°C for 6 hours to obtain NH4 in situ grown on the carbon cloth. + Intercalated hexagonal NMO electrode material.
[0011] Furthermore, in the above preparation method, in step 1), the sodium molybdate is Na2MoO4·2H2O, and the amount is 2.5 g; the concentrated hydrochloric acid is 37 wt.% HCl, and the amount is 5 mL; and the amount of deionized water is 20 mL.
[0012] Furthermore, in the above preparation method, in step 1), the stirring conditions for dissolving sodium molybdate in deionized water are: room temperature, 10 min; and the stirring conditions after adding concentrated hydrochloric acid are: room temperature, 20 min.
[0013] Furthermore, in the above-mentioned preparation method, in step 2), the cleaned carbon cloth is obtained by the following method: placing a 2*3 cm carbon cloth in an alcohol solution for 3 times of ultrasound, then washing it with deionized water, and drying it in a 60° C. vacuum drying oven for 6 hours.
[0014] Furthermore, in the above preparation method, in step 2), the soaking conditions are: room temperature, 5 minutes.
[0015] Furthermore, in the above preparation method, in step 2), the conditions for heating the carbon cloth on a heating plate after drying are: covering the carbon cloth with tin foil and heating at 320° C. for 10 min.
[0016] Furthermore, in the above preparation method, in step 3), the ammonium molybdate is (NH4)6Mo7O 24, the dosage is 0.53g; the concentrated nitric acid is 65wt.% HNO3, the dosage is 3mL; the dosage of the deionized water is 17mL; the dosage of the ammonium sulfate is 2g.
[0017] Furthermore, in the above preparation method, in step 3), the stirring conditions are: room temperature, 10 min.
[0018] Furthermore, in the above preparation method, in step 4), the conditions of the hydrothermal reaction are: 140° C., 30 min.
[0019] An NH4 in-situ grown on carbon cloth prepared by any of the preparation methods described above + Application of intercalated hexagonal NMO electrode material as negative electrode material in aqueous ammonium ion supercapacitors.
[0020] The beneficial effects of the present invention are:
[0021] 1. The present invention combines the seed hydrothermal method with the pre-intercalation strategy to grow NH4 in situ on the carbon cloth through the steps of seed hydrothermal and hydrothermal reaction. + Intercalated NMO electrode material, NH4 + The intercalation induced phase change of MoO3 material, and the interlayer spacing of MoO3 increased significantly, which was the main factor for the NH4 + Reversible insertion and removal provides convenient access.
[0022] 2. The present invention prepares NH4 grown in situ on carbon cloth by seed hydrothermal method and hydrothermal method. + Intercalated NMO electrode material, by pre-inserting NH4 into MoO3 + , forming hydrogen bonds with the main material, inhibiting the dissolution of the material and improving its electrochemical performance. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 It is the NH4 grown in situ on the carbon cloth in Example 1 + Scanning electron microscope images of the intercalated hexagonal NMO electrode material at different magnifications.
[0024] Figure 2 The MoO3 electrode material (a) in-situ grown on the carbon cloth in Comparative Example 1 and the NH4 in-situ grown on the carbon cloth in Example 1 + XRD spectrum of the intercalated hexagonal NMO electrode material (b).
[0025] Figure 3 It is the NH4 grown in situ on the carbon cloth in Example 2 + Constant current charge and discharge curves of the intercalated hexagonal NMO electrode material at different current densities.
[0026] Figure 4 It is a constant current charge and discharge curve diagram of the MoO3 electrode material in situ grown on carbon cloth in comparative example 2 at different current densities. DETAILED DESCRIPTION
[0027] Example 1
[0028] An in-situ grown NH4 on carbon cloth + The preparation method of the intercalated hexagonal NMO electrode material comprises the following steps:
[0029] (1) Solution preparation: Dissolve 2.5 g Na2MoO4·2H2O in 20 mL deionized water (DI), stir at room temperature for 10 min, add 5 mL HCl (37 wt.%), and stir for further 20 min.
[0030] (2) Seed hydrothermal method: Place a 2*3 cm carbon cloth in an alcohol solution and ultrasonicate it for 3 times, then wash it with deionized water and dry it in a 60°C vacuum drying oven for 6 hours to obtain a clean carbon cloth. Immerse the clean carbon cloth in the solution obtained in step 1) at room temperature for 5 minutes, blow dry the solution on the surface of the carbon cloth with a hair dryer, and after drying, place the carbon cloth on a heating plate, cover it with tin foil, and heat it at 320°C for 10 minutes.
[0031] (3) Prepare the precursor solution: 0.53 g (NH4)6Mo7O 24 , 3 mL HNO3 (65 wt.%), and DI (17 mL) were stirred in proportion at room temperature for 10 min, and then 2 g (NH4)2SO4 was added and stirred at room temperature for 10 min to obtain a precursor solution.
[0032] (4) Hydrothermal reaction: The carbon cloth treated in step 2) is placed in the precursor solution and subjected to hydrothermal reaction at 140° C. for 30 min.
[0033] (5) The carbon cloth obtained by the hydrothermal reaction was rinsed with anhydrous ethanol and deionized water three times respectively, and dried in a vacuum drying oven at 60°C for 6 h to obtain NH4 in situ grown on the carbon cloth. + Intercalated hexagonal NMO electrode material.
[0034] Figure 1 a, b, and c are scanning electron microscope images of NMO electrode materials at different magnifications. Figure 1 As can be seen from a, b, and c, the NMO electrode material grows directly on the carbon cloth and has a regular hexagonal crystal structure.
[0035] Comparative Example 1
[0036] A method for preparing a MoO3 electrode material grown in situ on a carbon cloth comprises the following steps:
[0037] (1) Solution preparation: Dissolve 2.5 g Na2MoO4·2H2O in 20 mL DI, stir at room temperature for 10 min, then add 5 mL HCl (37 wt.%) and stir for further 20 min.
[0038] (2) Seed hydrothermal method: Place a 2*3 cm carbon cloth in an alcohol solution and ultrasonicate it for 3 times, then wash it with deionized water and dry it in a 60°C vacuum drying oven for 6 hours to obtain a clean carbon cloth. Immerse the clean carbon cloth in the solution obtained in step 1) at room temperature for 5 minutes, blow dry the solution on the surface of the carbon cloth with a hair dryer, and after drying, place the carbon cloth on a heating plate, cover it with tin foil, and heat it at 320°C for 10 minutes.
[0039] (3) Prepare the precursor solution: 0.53 g (NH4)6Mo7O 24 , 3mL HNO3 (65wt.%), and DI (17mL) were stirred in proportion at room temperature for 10min.
[0040] (4) Hydrothermal reaction: The carbon cloth treated in step 2) is placed in the precursor solution and subjected to hydrothermal reaction at 140° C. for 30 min.
[0041] (5) The carbon cloth obtained by the hydrothermal reaction was rinsed three times with anhydrous ethanol and deionized water respectively, and dried in a vacuum drying oven at 60° C. for 6 h to obtain a MoO 3 electrode material in situ grown on the carbon cloth.
[0042] Figure 2 a and b are the XRD spectra of MoO3 and NMO electrode materials. Figure 2 It can be seen that MoO3 is orthorhombic molybdenum oxide, and the corresponding PDF card is 05-0508; NMO is hexagonal molybdenum oxide, and the corresponding PDF card is 21-0569; NH4 + The insertion of changed the crystal structure of the original molybdenum trioxide, and the interlayer spacing was expanded, resulting in better electrochemical performance.
[0043] Example 2
[0044] NH4 in situ grown on carbon cloth + Application of intercalated hexagonal NMO electrode material as negative electrode material in aqueous ammonium ion supercapacitors.
[0045] Method: NH4 grown in situ on carbon cloth + The intercalated hexagonal NMO electrode material was used as the working electrode, the calomel electrode was used as the reference electrode, the graphite foil was used as the counter electrode, and 1.0M (NH4)2SO4 was used as the electrolyte. The NMO electrode (1*1cm) was subjected to constant current charge and discharge tests in the potential range of -1 to 0V.
[0046] Figure 3 This is the constant current charge and discharge test curve of NMO composite electrode material. Figure 3 It can be seen that in 1.0M (NH4)2SO4 electrolyte, when the current density is 3mAcm -1 Its specific capacity can reach up to 193.0 mAh g -1 When the current density increases from 3 mA cm -1 Increase to 50mAcm -1 The specific capacity can reach 56.0% of the initial specific capacity, showing good rate performance, which proves the huge application potential of NMO electrode materials in aqueous ammonium ion supercapacitors.
[0047] Comparative Example 2
[0048] Application of MoO3 electrode material in situ grown on carbon cloth as negative electrode material in aqueous ammonium ion supercapacitors.
[0049] Method: With the MoO3 electrode material in situ grown on carbon cloth as the working electrode, calomel electrode as the reference electrode, graphite foil as the counter electrode, and 1.0M (NH4)2SO4 as the electrolyte, the MoO3 electrode (1*1cm) was subjected to constant current charge and discharge tests in the potential range of -1 to 0V.
[0050] Figure 4 This is the constant current charge and discharge test curve of MoO3 electrode material. Figure 4 It can be seen that in 1.0M (NH4)2SO4 electrolyte, when the current density is 3mA cm -1 Its specific capacity is 104.7 mAh g -1 When the current density increases from 3 mA cm -1 Increase to 50mA cm -1 When the specific capacity is only 30.4 mAh g -1 , its capacity and rate performance are lower than those of NMO electrode materials.
Claims
1. A NH4 in situ grown on carbon cloth + The method for preparing the intercalated hexagonal NMO electrode material is characterized in that: The steps include: 1) Prepare solution: dissolve sodium molybdate in deionized water, stir well, then add concentrated hydrochloric acid, and stir further; 2) Seed hydrothermal method: immerse the cleaned carbon cloth in the solution obtained in step 1), blow dry the solution on the surface of the carbon cloth with a hair dryer, and then heat it on a heating plate; 3) Prepare precursor solution: add ammonium molybdate and concentrated nitric acid into deionized water and stir evenly, then add ammonium sulfate and stir evenly; 4) Hydrothermal reaction: adding the carbon cloth treated in step 2) into the precursor solution for hydrothermal reaction; 5) The carbon cloth obtained in step 4) was rinsed with anhydrous ethanol and deionized water for three times respectively, and dried in a vacuum drying oven at 60°C for 6 hours to obtain NH4 in situ grown on the carbon cloth. + Intercalated hexagonal NMO electrode material.
2. The preparation method according to claim 1, characterized in that: In step 1), the sodium molybdate is Na2MoO4·2H2O, and the amount used is 2.5 g; the concentrated hydrochloric acid is 37 wt.% HCl, and the amount used is 5 mL; the amount of deionized water is 20 mL.
3. The preparation method according to claim 1, characterized in that: In step 1), the stirring conditions for dissolving sodium molybdate in deionized water are: room temperature, 10 min; and the stirring conditions after adding concentrated hydrochloric acid are: room temperature, 20 min.
4. The preparation method according to claim 1, characterized in that: In step 2), the cleaned carbon cloth is obtained by the following method: a 2*3 cm carbon cloth is ultrasonically treated in an alcohol solution for 3 times, then washed with deionized water, and dried in a vacuum drying oven at 60° C. for 6 h.
5. The preparation method according to claim 1, characterized in that: In step 2), the soaking conditions are: room temperature, 5 minutes.
6. The preparation method according to claim 1, characterized in that: In step 2), the carbon cloth is placed on a heating plate after drying and heated under the following conditions: the carbon cloth is covered with tin foil and heated at 320° C. for 10 min.
7. The preparation method according to claim 1, characterized in that: In step 3), the ammonium molybdate is (NH4)6Mo7O 24 , the dosage is 0.53g; the concentrated nitric acid is 65wt.% HNO3, the dosage is 3mL; the dosage of the deionized water is 17mL; the dosage of the ammonium sulfate is 2g.
8. The preparation method according to claim 1, characterized in that: In step 3), the stirring conditions are: room temperature, 10 min.
9. The preparation method according to claim 1, characterized in that: In step 4), the conditions of the hydrothermal reaction are: 140° C., 30 min.
10. NH4 in-situ grown on carbon cloth prepared by the preparation method according to any one of claims 1 to 9 + Application of intercalated hexagonal NMO electrode material as negative electrode material in aqueous ammonium ion supercapacitors.