One-dimensional hollow carbon nanomaterial constructed based on spherical holes and preparation method and application of one-dimensional hollow carbon nanomaterial
By employing magnetic field-induced assembly and block copolymer micellar confinement superassembly, carbon nanomaterials with interconnected macropores and uniform mesopores were successfully prepared, solving the preparation challenges in existing technologies and improving the material's application performance in the fields of high-efficiency electrodes and catalyst supports.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- INNER MONGOLIA UNIVERSITY
- Filing Date
- 2026-04-13
- Publication Date
- 2026-05-12
AI Technical Summary
Existing technologies make it difficult to easily prepare carbon nanomaterials that combine one-dimensional hollow morphology and ordered hierarchical channels, which limits their application in fields such as high-efficiency electrodes and catalyst supports.
A method combining magnetic field-induced assembly and block copolymer micelle-confined superassembly was adopted to construct a one-dimensional hollow framework using magnetic Fe3O4 nanospheres, and then superassembled on the inner wall of the pores using PS-PVP-PEO micelles to form carbon nanomaterials with interconnected spherical macropores and uniformly arranged spherical mesopores.
One-dimensional hollow carbon nanomaterials with good dispersibility and uniformity were prepared, which significantly improved the voltage and stability of high-performance evaporative DC power generation.
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Figure CN122010099A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of mesoporous materials technology, specifically relating to one-dimensional hollow carbon nanomaterials constructed based on spherical pores, their preparation methods, and applications. Background Technology
[0002] One-dimensional nanomaterials (such as nanowires, nanorods, and nanotubes) exhibit unique advantages in electron transport, mechanical strength, and as self-supporting substrates due to their anisotropic morphology. Among them, carbon nanotubes, as typical one-dimensional hollow carbon nanomaterials, possess significant structural advantages. First, the hollow structure ensures sufficient contact area between active sites and the solution, enabling the storage of more active substances and alleviating structural stress during chemical reactions. Second, the nanoscale structural units shorten electron / ion diffusion paths, improving reaction kinetics and the utilization rate of active substances. Finally, the one-dimensional structure facilitates electron transport. Based on these structural advantages, one-dimensional hollow carbon nanostructures have attracted considerable attention in fields such as catalysis, energy, and biomedicine.
[0003] Superstructured mesoporous materials refer to materials with a multi-level ordered mesoporous structure (2-50 nm), whose pore arrangement, composition distribution, and macroscopic morphology can be precisely controlled. Compared with traditional mesoporous materials (such as MCM-41 and SBA-15 with uniform pore structures), superstructured mesoporous materials form more complex topologies through the assembly of basic units (such as nanoparticles, micelles, and block copolymers), thus creating their own unique advantages. However, how to organically combine superstructured mesoporous materials with one-dimensional hollow carbon materials remains a challenge.
[0004] Common methods for synthesizing one-dimensional hollow mesoporous nanomaterials include template-based soft and hard template methods, electrospinning using large instruments, and sacrificial template methods based on the nanoscale Kirkendall effect and ion exchange reactions. However, most samples prepared using these methods are limited by small pore size or irregular porosity, resulting in the loading capacity of guest materials in the pores and the mass / ion transport efficiency being limited by their pore size and structure.
[0005] Therefore, developing a new method for the simple and controllable preparation of carbon nanomaterials with both interconnected one-dimensional hollow channels and orderly arranged spherical mesopores on the inner wall is of great significance for promoting their application in fields such as high-efficiency electrodes and catalyst supports. Summary of the Invention
[0006] To address the shortcomings of existing technologies in easily preparing carbon nanomaterials with both one-dimensional hollow morphology and ordered hierarchical channels, the present invention aims to provide a one-dimensional hollow carbon nanomaterial based on spherical pores, along with its preparation method and applications. This method combines magnetic field-induced assembly with block copolymer micellar confinement superassembly. Magnetic Fe3O4 nanospheres are used as structural guiding units to construct a one-dimensional hollow framework and internally interconnected spherical macropores (200-400 nm). Simultaneously, PS-PVP-PEO micelles are used to perform superassembly on the inner wall of the pores, transforming them into ordered spherical mesopores (20-50 nm). The synthesized one-dimensional hollow carbon nanomaterials have a width of approximately 250 nm and a length of 600 nm-1 μm, exhibiting good dispersibility and uniformity.
[0007] This invention is achieved through the following technical solution:
[0008] In a first aspect, the present invention provides a method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores, comprising the following steps:
[0009] Step 1: Fe3O4 nanospheres were synthesized using a solvothermal method. The obtained Fe3O4 nanospheres were dispersed in a mixed solvent composed of water, ethanol, and ammonia. Under the action of an external magnetic field, the Fe3O4 nanospheres arranged into a chain structure. Subsequently, a silicon source was added to coat the surface of the Fe3O4 nanosphere chain structure with a silica shell. The mass ratio of silicon source to Fe3O4 nanospheres was 1:20. After magnetic separation and washing, Fe3O4@SiO2 core-shell nanochains were obtained and dissolved in 30 mL of anhydrous ethanol for later use.
[0010] Step 2: Dissolve 40 mg of polystyrene-polytetravinylpyridine-polyethylene oxide triblock copolymer in 20 mL of anhydrous ethanol, stir until dissolved, and then place in an oven and heat at 70-100℃ for 3-5 h to obtain a PS-PVP-PEO micelle solution; mix the PS-PVP-PEO micelle solution with the Fe3O4@SiO2 core-shell nanochains obtained in Step 1, stir at room temperature to allow the PS-PVP-PEO micelles to superassemble on the surface of the Fe3O4@SiO2 core-shell nanochains, with a volume ratio of micelles to Fe3O4@SiO2 core-shell nanochains of 5:1; after the reaction is complete, collect the product by magnetic separation, and wash with water and ethanol to obtain Fe3O4@SiO2@micelle;
[0011] Step 3: Disperse the product obtained in Step 2 in 15 mL of water, add 6-7 mL of 0.01 mol / L tris(hydroxymethyl)aminomethane solution, and adjust the pH to 8.5; add dopamine hydrochloride for coating to form a dopamine coating layer, with a mass ratio of dopamine hydrochloride to Fe3O4@SiO2 core-shell nanochains of 10:1; after magnetic separation, washing, and drying, Fe3O4@SiO2@PDA nanofibers are obtained; place the product in a tube furnace and perform programmed temperature treatment under a nitrogen atmosphere; subsequently, treat the product with an etchant to remove the Fe3O4 core and SiO2 shell; finally, after washing and drying, one-dimensional hollow carbon nanomaterials are obtained.
[0012] Further, in step one, the Fe3O4 nanospheres are prepared by the following method: 4-6g of ferric chloride hexahydrate, 0.5-1g of sodium citrate and 5-9g of anhydrous sodium acetate are added to 30ml of ethylene glycol and dissolved. After being fully dissolved, the solution is placed in an oven and reacted at 180-200℃ for 5-10h to obtain Fe3O4 nanospheres.
[0013] Further, in step one, the diameter of the Fe3O4 nanospheres is 100-300 nm; the silicon source is selected from one or more of tetraethyl orthosilicate, 1,2-bis(triethoxysilyl)ethane (BTEE), methyl orthosilicate (TMOS), DMDMS, sodium silicate, methyltriethoxysilane (MTOS), and phenyltrimethoxysilane (PTMS).
[0014] Furthermore, in step two, the mixing volume ratio of PS-PVP-PEO micelle solution to Fe3O4@SiO2 core-shell nanochains is 5:1.
[0015] Furthermore, in step two, the concentration of the PS-PVP-PEO triblock copolymer in the solvent is 0.2-20 mg / mL.
[0016] Furthermore, in step two, the stirring speed is 60-600 rpm / min, and the reaction time is 3-15 h.
[0017] Further, in step three, the temperature-increasing process is as follows: first, the temperature is increased to 300-400℃ at 1-5℃ / min and held for 1-3 hours, then the temperature is increased to 700-900℃ at 2-10℃ / min and held for 1-3 hours; the etching agent is an aqueous solution of hydrofluoric acid.
[0018] Secondly, the present invention also provides a one-dimensional hollow carbon nanomaterial based on spherical pores, which is prepared by the method described in the first aspect. The one-dimensional hollow carbon nanomaterial has interconnected spherical macropores, and a single layer of spherical mesopores is uniformly arranged on the inner wall of the spherical macropores. The pore size of the spherical macropores is 220-350 nm, and the pore size of the spherical mesopores is 20-30 nm.
[0019] Thirdly, the one-dimensional hollow carbon nanomaterial with spherical mesopores synthesized in this invention has an application in high-performance evaporative DC power generation. Under the same load conditions, the power generation voltage of the one-dimensional hollow carbon nanomaterial with spherical mesopores is significantly higher than that of commercial carbon nanotubes.
[0020] Compared with the prior art, the advantages of the present invention are as follows:
[0021] 1. A method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores according to the present invention, wherein the prepared one-dimensional hollow nanomaterials have internally interconnected macropores (200-400 nm) and mesopores of uniform size and adjustable pore size (20-50 nm); the spherical mesopores are uniformly distributed on the inner wall of the spherical macropores; the width of the one-dimensional hollow carbon nanomaterials is about 300 nm and the length is 600 nm-1 μm, exhibiting good dispersibility and uniformity;
[0022] 2. In the preparation process of one-dimensional hollow carbon nanomaterials, the Fe3O4 nanospheres are synthesized by a solvothermal reaction, with a size of 100-300 nm. After being induced to form chains by a magnetic field, the Fe3O4 nanospheres serve as templates for forming spherical macropores. The size of the macropores in the one-dimensional hollow carbon nanomaterials can be adjusted by controlling the size of the Fe3O4 nanospheres. The size of the Fe3O4 nanospheres can be controlled by the content of sodium citrate and ferric chloride in the solvothermal reaction.
[0023] 3. The carbon source used in this invention is dopamine hydrochloride. The oligomers produced by dopamine hydrochloride further nucleate and assemble on the micelle surface under the action of hydrogen bonding, van der Waals forces, electrostatic bonding, etc., to form a core-shell structure. Attached Figure Description
[0024] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.
[0025] Figure 1 Transmission electron microscopy image of the one-dimensional hollow carbon nanomaterial prepared in Example 1;
[0026] Figure 2The nitrogen adsorption-desorption curves and pore size curves of the one-dimensional hollow carbon nanomaterials prepared in Example 1 are shown.
[0027] Figure 3 Transmission electron microscopy image of the one-dimensional hollow carbon nanomaterial prepared in Example 2;
[0028] Figure 4 Transmission electron microscopy image of the one-dimensional hollow carbon nanomaterial prepared in Example 3;
[0029] Figure 5 This is a schematic diagram illustrating the synthesis of the one-dimensional hollow carbon nanomaterial of the present invention;
[0030] Figure 6 Transmission electron microscopy image of the hollow carbon nanomaterials prepared in Example 4;
[0031] Figure 7 The transmission spectrum of the one-dimensional hollow carbon nanomaterial prepared in Example 5;
[0032] Figure 8 The power generation voltage of synthesized one-dimensional hollow carbon nanomaterials and commercial carbon nanotubes in DC power generation is shown in the figure.
[0033] Figure 9 The stability diagram of the synthesized one-dimensional hollow carbon nanomaterial in DC power generation. Detailed Implementation
[0034] To clearly and completely describe the technical solution and its specific working process of the present invention, the specific embodiments of the present invention are as follows, in conjunction with the accompanying drawings:
[0035] Example 1
[0036] like Figure 5 As shown, this embodiment provides a method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores, specifically including the following steps:
[0037] (1) 150 nm Fe3O4 nanospheres were synthesized using a solvothermal method as the core template. Specifically, 6.25 g of ferric chloride hexahydrate, 0.9 g of sodium citrate, and 6 g of anhydrous sodium acetate were dissolved in 30 mL of ethylene glycol. After complete dissolution, the mixture was placed in an oven and reacted at 200 °C for 10 h to obtain Fe3O4 nanospheres, which were then dissolved in 30 mL of anhydrous ethanol. The Fe3O4 nanospheres served as a hard template for constructing hollow interconnected macropores. At room temperature, 1 mL of the above Fe3O4 nanosphere solution was dissolved in a mixed solution of 15 mL of water and 55 mL of anhydrous ethanol. 0.5 mL of ammonia and 2 mL of LTEOS were added. A uniform magnetic field was applied under the reaction flask, and the Fe3O4 nanospheres were arranged into a chain structure. Subsequently, a silicon source was added to coat the surface of the Fe3O4 nanosphere chain structure with a silica shell. After magnetic separation and washing, Fe3O4@SiO2 core-shell nanochains were obtained.
[0038] (2) Triblock polystyrene-polytetravinylpyridine-polyethylene oxide (PS) 106 -PVP 47 -PEO 113 The block copolymer was dissolved in anhydrous ethanol at a concentration of 0.2-20 mg / mL. After ultrasonic dissolution, it was placed in an oven and reacted at 70°C for 3 hours to obtain a light blue transparent micelle solution. The Fe3O4@SiO2 core-shell nanochains obtained in step (1) were redispersed in 20 mL of ethanol-water mixed solvent, and 5 mL of the above micelle solution was added. The mixture was stirred at room temperature for 6 hours. The reactants were removed with a magnet and washed with water three times and alcohol three times in sequence. The experiment was repeated 5 times, and the 5 products were dissolved in 5 mL of anhydrous ethanol.
[0039] (3) Add tris(hydroxymethyl)aminomethane to the above product to adjust the pH to 8.5. Under vigorous stirring, add 120 mg of dopamine hydrochloride and react at room temperature for 14-24 h. Remove the reactants with a magnet, wash three times with water and three times with alcohol. Finally, dry the product in an oven. Place the dried product in a tube furnace and heat it from room temperature to 350 °C at a rate of 1 °C / min under a nitrogen atmosphere and hold for 3 h. Then heat it from 350 °C to 800 °C at a rate of 5 °C / min and hold for 2 h to obtain black Fe3O4@SiO2@PDA nanofibers. Finally, treat the sample with 1 wt%-2 wt% HF aqueous solution for 2 h to remove the reaction template. Centrifuge, wash repeatedly with water and ethanol until neutral, and dry at 60 °C to obtain the final product.
[0040] The microstructure of the one-dimensional hollow carbon nanomaterials prepared in Example 1 was observed using transmission electron microscopy, and the results are as follows: Figure 1 As shown, from Figure 1As can be seen from the figure, the one-dimensional hollow carbon nanomaterial prepared in this embodiment has interconnected spherical macropores, and a single layer of spherical mesopores is uniformly arranged on the inner wall of the spherical macropores. The pore size of the spherical macropores is 220-250 nm, and the pore size of the spherical mesopores is 22-26 nm.
[0041] Example 2
[0042] The difference between this embodiment and Embodiment 1 is that the triblock copolymer used in step (2) is PS. 69 -PVP 47 -PEO 113 (i.e., the PS block length is relatively short), the rest of the steps and conditions are exactly the same.
[0043] The microstructure of the one-dimensional hollow carbon nanomaterials prepared in Example 2 was observed using transmission electron microscopy, and the results are as follows: Figure 2 As shown, from Figure 2 As can be seen from the figure, the one-dimensional hollow carbon nanomaterial prepared in this embodiment has interconnected spherical macropores, and a single layer of spherical mesopores is uniformly arranged on the inner wall of the spherical macropores. The pore size of the spherical macropores is 220-250 nm, and the pore size of the spherical mesopores is 20-25 nm.
[0044] Example 3
[0045] The difference between this embodiment and Example 1 is that in step (1), when synthesizing Fe3O4 nanospheres, the amount of sodium citrate is increased to 1.1g to synthesize Fe3O4 nanospheres with larger particle size. The remaining steps and conditions are basically the same as in Example 1.
[0046] The microstructure of the one-dimensional hollow carbon nanomaterials prepared in Example 3 was observed using transmission electron microscopy, and the results are as follows: Figure 3 As shown, from Figure 3 As can be seen from the figure, the one-dimensional hollow carbon nanomaterial prepared in this embodiment has interconnected spherical macropores, and a single layer of spherical mesopores is uniformly arranged on the inner wall of the spherical macropores. The pore size of the spherical macropores is 300-350nm, and the pore size of the spherical mesopores is 28-30nm.
[0047] Comparative Example 1
[0048] This comparative example provides a method for preparing hollow mesoporous carbon spheres, specifically including the following steps:
[0049] (1) Fe3O4 nanospheres of 150 nm were synthesized using a solvothermal method as the core template. Specifically, 6.25 g of ferric chloride hexahydrate, 0.9 g of sodium citrate, and 6 g of anhydrous sodium acetate were dissolved in 30 mL of ethylene glycol. After complete dissolution, the mixture was placed in an oven and reacted at 200 °C for 10 h to obtain Fe3O4 nanospheres, which were then dissolved in 30 mL of anhydrous ethanol. The Fe3O4 nanospheres served as the hard template for constructing hollow interconnected macropores. At room temperature, 1 mL of the above Fe3O4 nanosphere solution was dissolved in a mixed solution of 15 mL of water and 55 mL of anhydrous ethanol, and 0.5 mL of ammonia and 2 mL of TEOS were added. After magnetic separation and washing, Fe3O4@SiO2 core-shell nanochains were obtained.
[0050] (2) Triblock polystyrene-polytetravinylpyridine-polyethylene oxide (PS) 106 -PVP 47 -PEO 113 The block copolymer was dissolved in anhydrous ethanol at a concentration of 0.2-20 mg / mL. After ultrasonic dissolution, it was placed in an oven and reacted at 70°C for 3 hours to obtain a light blue transparent micelle solution. The Fe3O4@SiO2 core-shell nanospheres obtained in step (1) were redispersed in 20 mL of ethanol-water mixed solvent, and 5 mL of the above micelle solution was added. The mixture was stirred at room temperature for 6 hours. The reactants were removed with a magnet and washed with water three times and alcohol three times in sequence. The experiment was repeated 5 times, and the 5 products were dissolved in 5 mL of anhydrous ethanol.
[0051] (3) Add 0.01 mol / L of tris(hydroxymethyl)aminomethane to the above product until pH=8.5. Add 120 mg of dopamine hydrochloride under vigorous stirring and react at room temperature for 14-24 h. Remove the reactants with a magnet, wash three times with water and three times with alcohol. Finally, dry the product in an oven. Place the dried product in a tube furnace and heat it from room temperature to 350 °C at a rate of 1 °C / min under a nitrogen atmosphere and hold for 3 h. Then heat it from 350 °C to 800 °C at a rate of 5 °C / min and hold for 2 h to obtain black Fe3O4@SiO2@PDA nanoparticles. Finally, treat the sample with 1 wt%-2 wt% HF aqueous solution for 2 h to remove the reaction template. Centrifuge, wash repeatedly with water and ethanol until neutral, and dry at 60 °C to obtain the final product.
[0052] The difference between this comparative example and Example 1 is that no uniform magnetic field was added during the synthesis of Fe3O4@SiO2 core-shell nanochains in step (1). The remaining steps and conditions are basically the same as in Example 1. Because there are no magnetic field lines, the Fe3O4 nanospheres cannot magnetically assemble along the magnetic field lines. Therefore, the intermediate product synthesized is Fe3O4@SiO2 core-shell nanospheres instead of Fe3O4@SiO2 core-shell nanochains.
[0053] The hollow carbon nanomaterials prepared in Comparative Example 1 were observed for their microstructure using transmission electron microscopy. The results are as follows: Figure 6 As shown, from Figure 6 As can be seen, the hollow carbon nanospheres prepared in this comparative example have uniformly distributed 20-30 nm spherical mesopores on their surface. The size of the spherical macropores is 250-300 nm.
[0054] Comparative Example 2
[0055] This comparative example provides a method for preparing one-dimensional hollow carbon nanomaterials, specifically including the following steps:
[0056] (1) 150 nm Fe3O4 nanospheres were synthesized using a solvothermal method as the core template. Specifically, 6.25 g of ferric chloride hexahydrate, 0.9 g of sodium citrate, and 6 g of anhydrous sodium acetate were dissolved in 30 mL of ethylene glycol. After complete dissolution, the mixture was placed in an oven and reacted at 200 °C for 10 h to obtain Fe3O4 nanospheres, which were then dissolved in 30 mL of anhydrous ethanol. The Fe3O4 nanospheres served as a hard template for constructing hollow interconnected macropores. At room temperature, 1 mL of the above Fe3O4 nanosphere solution was dissolved in a mixed solution of 15 mL of water and 55 mL of anhydrous ethanol. 0.5 mL of ammonia and 2 mL of TEOS were added. A uniform magnetic field was applied under the reaction flask, and the Fe3O4 nanospheres were arranged into a chain structure. Subsequently, a silicon source was added to coat the surface of the Fe3O4 nanosphere chain structure with a silica shell. After magnetic separation and washing, Fe3O4@SiO2 core-shell nanochains were obtained. Repeat the experiment 5 times, and dissolve the 5 products in 5 mL of anhydrous ethanol.
[0057] (2) Add 0.01 mol / L of tris(hydroxymethyl)aminomethane to the above product until pH=8.5. Add 120 mg of dopamine hydrochloride under vigorous stirring and react at room temperature for 14-24 h. Remove the reactants with a magnet, wash three times with water and three times with alcohol. Finally, dry the product in an oven. Place the dried product in a tube furnace and heat it from room temperature to 350 °C at a rate of 1 °C / min under a nitrogen atmosphere and hold for 3 h. Then heat it from 350 °C to 800 °C at a rate of 5 °C / min and hold for 2 h to obtain black Fe3O4@SiO2@PDA nanofibers. Finally, treat the sample with 1 wt%-2 wt% HF aqueous solution for 2 h to remove the reaction template. Centrifuge, wash repeatedly with water and ethanol until neutral, and dry at 60 °C to obtain the final product.
[0058] The difference between this comparative example and Example 1 is that triblock polystyrene-polytetravinylpyridine-polyethylene oxide (PS) is not added before step (2). 106 -PVP47 -PEO 113 Block copolymers were used. Dopamine was directly coated onto the outer surface of Fe3O4@SiO2 core-shell nanochains. Because PS-PVP-PEO triblock copolymer micelles were not added, the surface of the Fe3O4@SiO2 core-shell nanochains could not undergo micellar superassembly, resulting in a smooth surface. Further coating with dopamine and etching yielded a smooth one-dimensional hollow carbon nanomaterial with no spherical mesopores on its surface.
[0059] The microstructure of the one-dimensional hollow carbon nanomaterial prepared in Comparative Example 2 was observed using transmission electron microscopy, and the results are as follows: Figure 7 As shown, from Figure 7 As can be seen, the material prepared in this comparative example is a one-dimensional hollow carbon nanomaterial with interconnected spherical macropores and no spherical mesopores appearing on the material surface. The size of the spherical macropores is 150-200 nm.
[0060] Example 4
[0061] The one-dimensional hollow carbon nanomaterial with spherical pores synthesized in Example 1 and commercial carbon nanotubes were respectively tested for their evaporative DC power generation performance. The specific steps are as follows:
[0062] The one-dimensional hollow nanomaterials with spherical pores prepared in Example 1 and commercial carbon nanotubes were oxidized by heating with concentrated sulfuric acid and concentrated nitric acid, respectively. Excess acid was then removed by dialysis with deionized water, the samples were dried, and dispersed in anhydrous ethanol. The dispersion was sprayed onto an acrylic plate using a spray gun, with wires attached to both ends of the plate. The acrylic plate was then immersed in water for further testing.
[0063] The one-dimensional hollow carbon nanomaterial with spherical pores synthesized in Example 1 and commercial carbon nanotubes were respectively tested for their evaporative DC power generation performance. Figure 8 As can be seen, under the same conditions, the power generation voltage of the one-dimensional hollow carbon nanomaterial with spherical pores synthesized in Example 1 is much higher than that of commercial carbon nanotubes. Therefore, the one-dimensional hollow carbon nanomaterial with spherical pores prepared in this invention has better performance in evaporative DC power generation.
[0064] The stability of the one-dimensional hollow carbon nanomaterial with spherical pores synthesized in Example 1 was tested for evaporative DC power generation. Figure 9 As can be seen, after 12,000 seconds of continuous power generation, the power generation performance of the one-dimensional hollow carbon nanomaterial constructed with spherical pores did not decrease, and remained at a power generation voltage of approximately 1.85. This indicates that the one-dimensional hollow carbon nanomaterial constructed with spherical pores prepared in this invention exhibits good stability in evaporative DC power generation.
[0065] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.
[0066] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.
[0067] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.
Claims
1. A method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores, characterized in that, Includes the following steps: Step 1: Fe3O4 nanospheres were synthesized using a solvothermal method and then dispersed in a mixed solvent. Under the action of an external magnetic field, the Fe3O4 nanospheres arranged into a chain structure. Subsequently, a silicon source was added to coat the surface of the Fe3O4 nanosphere chain structure with a silica shell. The mass ratio of silicon source to Fe3O4 nanospheres was 1:
20. After magnetic separation and washing, Fe3O4@SiO2 core-shell nanochains were obtained and dissolved for later use. Step 2: Dissolve the polystyrene-polytetravinylpyridine-polyethylene oxide triblock copolymer in anhydrous ethanol, stir until dissolved, and then place in an oven and heat at 70-100℃ for 3-5 hours to obtain a PS-PVP-PEO micelle solution. Mix the PS-PVP-PEO micelle solution with the Fe3O4@SiO2 core-shell nanochains obtained in Step 1, and stir at room temperature to allow the PS-PVP-PEO micelles to superassemble on the surface of the Fe3O4@SiO2 core-shell nanochains. The volume ratio of micelles to Fe3O4@SiO2 core-shell nanochains used is 5:
1. After the reaction is complete, collect the product by magnetic separation and wash with water and ethanol to obtain Fe3O4@SiO2@micelle. Step 3: Disperse the product obtained in Step 2 in water, add 6-7 mL of 0.01 mol / L tris(hydroxymethyl)aminomethane solution, and adjust the pH to 8.5; add dopamine hydrochloride for coating to form a dopamine coating layer, with a mass ratio of dopamine hydrochloride to Fe3O4@SiO2 core-shell nanochains of 10:1; after magnetic separation, washing, and drying, Fe3O4@SiO2@PDA nanofibers are obtained; place the product in a tube furnace and perform programmed temperature treatment under a nitrogen atmosphere; subsequently, treat the product with an etchant to remove the Fe3O4 core and SiO2 shell; finally, after washing and drying, one-dimensional hollow carbon nanomaterials are obtained.
2. The method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores as described in claim 1, characterized in that, In step one, the Fe3O4 nanospheres are prepared by the following method: 4-6g of ferric chloride hexahydrate, 0.5-1g of sodium citrate and 5-9g of anhydrous sodium acetate are added to 30ml of ethylene glycol and dissolved. After complete dissolution, the solution is placed in an oven and reacted at 180-200℃ for 5-10h to obtain Fe3O4 nanospheres. The mixed solvent is composed of water, ethanol and ammonia.
3. The method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores as described in claim 1, characterized in that, In step one, the diameter of the Fe3O4 nanospheres is 100-300 nm; the silicon source is selected from one or more of tetraethyl orthosilicate, 1,2-bis(triethoxysilyl)ethane, methyl orthosilicate, DMDMS, sodium silicate, methyltriethoxysilane, and phenyltrimethoxysilane.
4. The method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores as described in claim 1, characterized in that, In step two, the mixing volume ratio of PS-PVP-PEO micelle solution to Fe3O4@SiO2 core-shell nanochains is 5:
1.
5. The method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores as described in claim 1, characterized in that, In step two, the concentration of the polystyrene-polytetravinylpyridine-polyethylene oxide triblock copolymer in the solvent is 0.2-20 mg / mL.
6. The method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores as described in claim 1, characterized in that, In step two, the stirring speed is 60-600 rpm / min, and the reaction time is 3-15 h.
7. The method for preparing one-dimensional hollow carbon nanomaterials based on spherical pores as described in claim 1, characterized in that, In step three, the temperature rise process is as follows: first, the temperature is increased to 300-400℃ at 1-5℃ / min and held for 1-3 hours, then the temperature is increased to 700-900℃ at 2-10℃ / min and held for 1-3 hours; the etching agent is an aqueous solution of hydrofluoric acid.
8. A one-dimensional hollow carbon nanomaterial constructed based on spherical pores, characterized in that, The one-dimensional hollow carbon nanomaterial prepared by the method according to any one of claims 1-7 has interconnected spherical macropores, and a single layer of spherical mesopores is uniformly arranged on the inner wall of the spherical macropores. The pore size of the spherical macropores is 220-350 nm, and the pore size of the spherical mesopores is 20-30 nm.
9. The application of the one-dimensional hollow carbon nanomaterial based on spherical pores as described in claim 8 in high-performance evaporative DC power generation.