Preparation method and application of one-dimensional reticular nanotube MOF derived selenide@porous carbon material

Abstract

This invention discloses a method for preparing one-dimensional network nanotube MOF-derived selenide@porous carbon materials and their applications. The method includes the following steps: dispersing ZnCo-BTC nanowires in an ethanol-water solution to form a uniform suspension A; dissolving 2-methylimidazole in an ethanol-water solution to form a solution B; preheating solution B to the reaction temperature in a water bath, pouring in suspension A, stirring at a constant temperature, centrifuging the product, washing it multiple times with ethanol and water, and finally drying it to obtain a one-dimensional tubular MOF material. Annealing this one-dimensional tubular MOF material with melamine in an argon atmosphere yields a porous carbon nanotube material with a network structure. Mixing the one-dimensional network porous carbon nanotube material with selenium powder and annealing it under argon protection yields the one-dimensional network nanotube MOF-derived selenide@porous carbon material. This invention is simple to operate, the process is controllable, and the prepared product can be widely used in electrochemical energy storage, separation, catalysis, and drug sustained release.

Description

Technical Field

[0001] This invention belongs to the field of functional nanomaterial synthesis technology, specifically relating to the preparation method and application of one-dimensional network nanotube MOF-derived selenide@porous carbon materials. Background Technology

[0002] In recent years, sodium-ion batteries (SIBs) have shown great potential in large-scale energy storage systems due to their abundant sodium resources and potential low cost. Commonly used anode materials for SIBs can be broadly classified into intercalated anodes, alloy anodes, and conversion anodes. Intercalated anodes (such as hard carbon, TiO2, Na2Ti3O7, etc.) have small volume changes but limited capacity. Alloy anodes (such as Sn, Sb, P, etc.) have high theoretical capacity but are severely affected by volume changes. Conversion anodes (oxides, sulfides, selenides, phosphides, etc.) typically have high theoretical capacity, small volume changes, and good reversibility, exhibiting superior overall performance. Metal-organic frameworks (MOFs) are a new type of crystalline porous material composed of metal ions (metal clusters) and organic ligands. These materials generally possess high specific surface area, high porosity, and tunable structural composition, and are widely used in electrochemical energy storage, gas adsorption and storage, catalysis, drug carriers, or porous templates.

[0003] Currently, there are relatively few methods for preparing one-dimensional metal selenides and carbon heterostructures, and the synthesis processes related to these materials are quite complex. They may also involve problems such as consuming a lot of energy, low yield, and unstable product quality. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing one-dimensional tubular MOF materials and the preparation and application of one-dimensional network nanotube MOF-derived selenide@porous carbon materials, which can not only be applied to electrochemical sodium ion storage, but also extended to other fields.

[0005] In one aspect of the present invention, a method for preparing one-dimensional nanotube MOF materials is provided. According to an embodiment of the present invention, the method includes the following steps:

[0006] (1) Preparation of ZnCo-BTC nanowires: 1,3,5-pyromellitic acid was dissolved in deionized water to form solution I, and zinc acetate dihydrate and cobalt acetate tetrahydrate were dissolved in deionized water to form solution II. When solution I was preheated to 90-100℃ in an oil bath, solution II was added to solution I and the reaction was stirred at a constant temperature for 8-12 min. The product was separated by centrifugation, washed with ethanol and dried to obtain ZnCo-BTC nanowire powder.

[0007] (2) Preparation of nanotube MOF: ZnCo-BTC nanowire powder was dispersed in an ethanol aqueous solution to form a uniform suspension A. 2-methylimidazole was dissolved in an ethanol aqueous solution to form a solution B. Solution B was preheated to the reaction temperature in a water bath. Suspension A was added to solution B. After stirring at a constant temperature, the product was centrifuged and then washed with ethanol. Finally, it was dried to obtain a one-dimensional tubular MOF material.

[0008] In addition, the method for preparing one-dimensional nanotube MOF materials according to the above embodiments of the present invention may also have the following additional technical features:

[0009] In some embodiments of the present invention, in step (1), the concentration of 1,3,5-pyromellitic acid in solution I is 0.020-0.024 mol / L, the concentration of cobalt acetate tetrahydrate in solution II is 0.08-0.12 mol / L, and the concentration of zinc acetate dihydrate is 0.08-0.12 mol / L; the volume ratio of solution I to solution II is 10:1-8:1; the drying temperature is 75-85℃, and the drying time is 8-12 h.

[0010] In some embodiments of the present invention, in step (2), the concentration of suspension A is 0.67 to 0.93 g / L, the concentration of solution B is 1.63 to 2.21 mol / L, and the volume ratio of water to ethanol in the ethanol aqueous solution is 1:9 to 3:7.

[0011] In some embodiments of the present invention, in step (2), the volume ratio of suspension A to solution B is 1:3 to 1:1.5; the temperature in the water bath is 60 to 80°C, the stirring time is 18 to 22 min; the number of times of ethanol washing is 2 to 4; the drying temperature is 75 to 85°C, and the drying time is 10 to 20 h.

[0012] In another aspect of the present invention, the present invention proposes a one-dimensional nanotube MOF material prepared according to the preparation method of the one-dimensional nanotube MOF material described above.

[0013] In another aspect, the present invention proposes a method for preparing one-dimensional network nanotube MOF-derived selenide@porous carbon materials. According to an embodiment of the present invention, the method includes the following steps:

[0014] (1) The one-dimensional nanotube MOF material and melamine were placed in a tube furnace and annealed under argon protection to obtain a one-dimensional network porous carbon nanotube material containing zinc and cobalt metal elements.

[0015] (2) After uniformly mixing one-dimensional porous carbon nanotube material containing zinc and cobalt metal elements with selenium powder, one-dimensional porous carbon material MOF-derived selenide is obtained by argon protection annealing.

[0016] In addition, the preparation method of one-dimensional network nanotube MOF-derived selenide@porous carbon material according to the above embodiments of the present invention may also have the following additional technical features:

[0017] In some embodiments of the present invention, in step (1), the mass ratio of one-dimensional nanotube MOF material to melamine is 1:2 to 1:4, the annealing temperature is 600 to 800°C, and the holding time is 1.5 to 2.5 h.

[0018] In some embodiments of the present invention, in step (2), the mass ratio of one-dimensional mesh porous carbon nanotube material to selenium powder is 1:1.5 to 1:2.5, the annealing temperature is 300 to 500°C, and the holding time is 1.5 to 2.5 h.

[0019] In another aspect of the present invention, the present invention proposes a one-dimensional network nanotube MOF-derived selenide@porous carbon material prepared according to the preparation method of the one-dimensional network nanotube MOF-derived selenide@porous carbon material described above.

[0020] In another aspect of the invention, the application of one-dimensional network nanotube MOF-derived selenide@porous carbon materials is proposed. According to embodiments of the invention, the material is used to prepare anode materials for sodium-ion batteries.

[0021] Compared with the prior art, the advantages of this invention are as follows:

[0022] 1. This invention successfully achieved the controllable preparation and morphology regulation of one-dimensional MOF materials, and obtained one-dimensional network nanotube MOF-derived selenides@porous carbon materials by indirect selenization under an argon atmosphere. Metal selenides have excellent theoretical capacity, while MOF materials themselves have high porosity and high specific surface area, which is beneficial for better contact between electrode materials and electrolytes and for electrolyte diffusion. Combining one-dimensional tubular structures with metal selenides allows for the formation of heterogeneous interfaces between selenides and carbon, providing abundant lattice distortions and defects that enhance ion-electron transport and reaction kinetics. The one-dimensional network tubular structure, compared to other nanostructures, has a larger specific surface area, providing more ion storage sites for electrochemical reactions and facilitating redox reactions. Furthermore, compared to solid structures, hollow tubular structures exhibit better structural stability, effectively mitigating volume changes during charge-discharge processes and resulting in superior cycle stability. Therefore, using one-dimensional network nanotube MOF-derived selenides@porous carbon materials as the anode material for high-performance sodium-ion batteries can significantly improve their electrochemical performance.

[0023] 2. The preparation method adopted in this invention is safe and simple, with simple synthesis conditions, easy operation, high yield, and low production cost. The one-dimensional network nanotube MOF-derived selenide@porous carbon material provided by this invention can not only be applied to electrochemical sodium ion storage, but also extended to other fields, such as separation, catalysis, drug sustained release, and energy.

[0024] 3. This invention develops a simple and efficient method for producing MOF-derived selenide@porous carbon materials. The selenide@carbon heterostructure prepared by this method can perfectly retain the one-dimensional network tubular morphology, while simultaneously achieving stable construction of the selenide-porous carbon heterostructure interface. Compared with other methods, the synthesis scheme used in this invention is simple, has a high yield, and produces stable product quality. Attached Figure Description

[0025] Figure 1 FESEM image of ZnCo-BTC nanowires prepared in Example 1;

[0026] Figure 2 FESEM (left) and TEM (right) images of the one-dimensional nanotube MOF material prepared in Example 1;

[0027] Figure 3 FESEM (left) and TEM images (right) of the one-dimensional network porous carbon nanotube material prepared in Example 2;

[0028] Figure 4 FESEM (left) and TEM (right) images of the one-dimensional network nanotube MOF-derived selenide@porous carbon material prepared in Example 2;

[0029] Figure 5 The XRD pattern of the one-dimensional network porous carbon nanotube material prepared in Example 2;

[0030] Figure 6 XRD pattern of the one-dimensional network nanotube MOF-derived selenide@porous carbon material prepared in Example 2;

[0031] Figure 7 The graphs show the electrochemical performance of the CR2032 coin cell prepared in Example 3. The left graph shows the discharge specific capacity at different current densities, and the right graph shows the discharge specific capacity at 2 A / g. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0033] Example 1

[0034] Preparation of ZnCo-BTC nanowire powder:

[0035] (1) Dissolve 0.42g of 1,3,5-pyromellitic acid in 90ml of deionized water to form solution I. Dissolve 0.25g of cobalt acetate tetrahydrate and 0.22g of zinc acetate dihydrate in 10ml of deionized water to form solution II. When solution I is preheated to 100℃ in an oil bath, add solution II to solution I and stir at a constant temperature for 10min.

[0036] (2) The product was centrifuged, washed with ethanol, and dried in an oven at 80°C for 10 hours to obtain ZnCo-BTC nanowire powder.

[0037] Figure 1 The ZnCo-BTC nanowire material prepared in this embodiment shows that the unconverted MOFs material exhibits a smooth one-dimensional nanowire morphology.

[0038] Example 2

[0039] Preparation of one-dimensional nanotube MOF materials:

[0040] (1) Take 20 mg of the ZnCo-BTC nanowire powder prepared in Example 1 and disperse it in 30 ml of ethanol aqueous solution (V 乙醇 :V 水 =9:1), forming a homogeneous suspension A, 4g of 2-methylimidazole dissolved in 10ml of ethanol aqueous solution (V 乙醇 :V 水 =9:1), forming solution B. Place B in a water bath and preheat to 70°C. Add suspension A and stir at a constant temperature for 20 minutes.

[0041] (2) The product was centrifuged, washed three times with ethanol, and dried in an oven at 80°C for 10 hours to obtain one-dimensional nanotube MOF material.

[0042] Figure 2 The images show FESEM and TEM images of the one-dimensional nanotube MOF material powder prepared in this embodiment. They demonstrate that after transformation, the smooth, solid nanowires become hollow tubular structures with a surface composed of rough particles.

[0043] Example 3

[0044] Preparation of one-dimensional network nanotube MOF-derived selenides@porous carbon materials:

[0045] (1) The one-dimensional nanotube MOF material prepared in Example 1 and melamine were placed in two sintering boats at a mass ratio of 1:3 and annealed together under argon protection. The heating rate of the tube furnace was 2℃ / min, the annealing temperature was 700℃, and the holding time was 2h; one-dimensional network porous carbon nanotube material was obtained.

[0046] (2) After uniformly mixing the one-dimensional network porous carbon nanotube material with selenium powder at a mass ratio of 1:2, the mixture was annealed under argon protection at a temperature of 400℃ and a heating rate of 2℃ / min. -1 Incubate for 2 hours to obtain one-dimensional network nanotube MOF-derived selenide@porous carbon material.

[0047] Figure 3 These are FESEM and TEM images of the one-dimensional network carbon nanotube material prepared in this embodiment. They show that after annealing the one-dimensional tubular MOF material with melamine, fine branched carbon nanotubes grow on the surface, while the main tube surface exhibits a network structure. Figure 5 This is the XRD pattern of a one-dimensional network carbon nanotube material. It can be seen that the phases of the material after carbonization are carbon, reduced Co, and Co3ZnC.

[0048] Figure 4 These are FESEM and TEM images of the one-dimensional network nanotube MOF-derived selenide@porous carbon material prepared in this embodiment. It can be seen that the morphology after selenization is basically retained after carbonization, while the cobalt particles are transformed into cobalt selenide after annealing and are confined to the ends of the nanotubes, thus achieving the successful preparation of selenide@porous carbon heterostructure. Figure 6 This is an XRD pattern of one-dimensional network nanotube MOF-derived selenide@porous carbon, showing that the material is completely transformed into carbon, ZnSe, and CoSe2.

[0049] Example 4

[0050] A method for preparing a sodium-ion battery:

[0051] (1) Preparation of working electrode: The one-dimensional mesh nanotube MOF-derived selenide@porous carbon material prepared in Example 2 was uniformly mixed with conductive carbon black and PVDF in a mass ratio of 8:1:1 and dissolved in 1-methyl-2-pyrrolidone (NMP) to form a slurry. The slurry was then uniformly coated on a copper foil current collector and dried in a vacuum drying oven at 60°C for 24 hours. The slicing was then used to prepare the working electrode.

[0052] (2) Assemble the battery: Using sodium sheet as positive electrode material and glass fiber as separator, and using secondary electrolyte, CR2032 button battery is assembled in a glove box filled with argon gas.

[0053] Performance testing: 0.5V~3V vs Na + The rate performance of the battery was tested at current densities of 0.1 A / g, 0.2 A / g, 0.5 A / g, 1 A / g, 2 A / g, 5 A / g, and 10 A / g within the voltage range of Na. (0.5V~3V vs Na) + The battery's cycle performance was tested at a current density of 2 A / g within the voltage range of / Na.

[0054] Figure 7 This embodiment presents the electrochemical performance tests conducted on the CR2032 coin cell. It can be seen that the one-dimensional network nanotube MOF-derived selenide@porous carbon exhibits good specific capacity at different current densities, especially at high current densities, and also demonstrates excellent capacity retention after 1000 cycles. This is mainly attributed to the high theoretical capacity of the selenide, the rapid electrochemical reaction kinetics, and the improvement in electrode material volume change due to the one-dimensional tubular structure.

[0055] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the present invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A method for preparing one-dimensional network nanotube MOF-derived selenide@porous carbon materials, characterized in that, Includes the following steps: (1) Disperse ZnCo-BTC nanowire powder in an ethanol aqueous solution to form a uniform suspension A. Dissolve 2-methylimidazole in an ethanol aqueous solution to form a solution B. Preheat solution B to the reaction temperature in a water bath. Add suspension A to solution B. After stirring the reaction at a constant temperature, centrifuge the product, wash it with ethanol, and finally dry it to obtain a one-dimensional tubular MOF material. (2) The one-dimensional nanotube MOF material and melamine were placed in a tube furnace and annealed under argon protection to obtain a one-dimensional network porous carbon nanotube material containing zinc and cobalt metal elements. The mass ratio of the one-dimensional nanotube MOF material to melamine was 1:2 to 1:4, the annealing temperature was 600 to 800 °C, and the holding time was 1.5 to 2.5 h. (3) After uniformly mixing one-dimensional porous carbon nanotube material containing zinc and cobalt metal elements with selenium powder, one-dimensional porous carbon nanotube MOF-derived selenide is obtained by argon protection annealing.

2. The method for preparing one-dimensional network nanotube MOF-derived selenide@porous carbon materials according to claim 1, characterized in that, The preparation method of the ZnCo-BTC nanowire powder includes the following steps: preparing ZnCo-BTC nanowires: dissolving 1,3,5-pyromellitic acid in deionized water to form solution I, dissolving zinc acetate dihydrate and cobalt acetate tetrahydrate in deionized water to form solution II, preheating solution I to 90-100 ℃ in an oil bath, adding solution II to solution I, stirring at a constant temperature for 8-12 min, centrifuging the product, washing it with ethanol and drying it to obtain ZnCo-BTC nanowire powder.

3. The method for preparing one-dimensional network nanotube MOF-derived selenide@porous carbon material according to claim 2, characterized in that: The concentration of 1,3,5-trimethylbenzenecarboxylic acid in solution I is 0.020–0.024 mol / L, the concentration of cobalt acetate tetrahydrate in solution II is 0.08–0.12 mol / L, and the concentration of zinc acetate dihydrate is 0.08–0.12 mol / L; the volume ratio of solution I to solution II is 10:1–8:1; the drying temperature is 75–85 ℃, and the drying time is 8–12 h.

4. The method for preparing one-dimensional network nanotube MOF-derived selenide@porous carbon material according to claim 1, characterized in that: In step (1), the concentration of suspension A is 0.67–0.93 g / L, the concentration of solution B is 1.63–2.21 mol / L, and the volume ratio of water to ethanol in the ethanol-water solution is 1:9–3:

7.

5. The method for preparing one-dimensional network nanotube MOF-derived selenide@porous carbon material according to claim 1, characterized in that: In step (1), the volume ratio of suspension A to solution B is 1:3 to 1:1.5; the temperature in the water bath is 60 to 80 ℃, and the stirring time is 18 to 22 min; the number of times of ethanol washing is 2 to 4; the drying temperature is 75 to 85 ℃, and the drying time is 10 to 20 h.

6. The method for preparing one-dimensional network nanotube MOF-derived selenide@porous carbon material according to claim 1, characterized in that: In step (2), the mass ratio of one-dimensional mesh porous carbon nanotube material to selenium powder is 1:1.5~1:2.5, the annealing temperature is 300~500 ℃, and the holding time is 1.5-2.5 h.

7. A one-dimensional network nanotube MOF-derived selenide@porous carbon material prepared by the preparation method of any one of claims 1-6.

8. An application of the one-dimensional network nanotube MOF-derived selenide@porous carbon material according to claim 7, characterized in that: The material is used to prepare the negative electrode material for sodium-ion batteries.

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