Preparation method of heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotube

Abstract

The invention discloses a preparation method and a reaction device of a heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotube, and the preparation method comprises the following steps: S1, introducing inert gas into the reaction device filled with a monomer dissolved in an organic solvent, and adding a required heteroatom dopant under the inert atmosphere; wherein the reaction device comprises a micro pump which can be used for accurately controlling the delivery rate of FeCl3. FeCl3 is safely conveyed into a reaction system in a leakage-free manner through a closed conveying system; s2, a Lewis acid catalyst is added, a self-crosslinking Friedel-Crafts reaction is carried out, and the whole reaction process is under inert gas protection; s3, washing a product generated in the previous step with ethanol and acetone, and purifying and drying to obtain a super-crosslinked polymer; s4, performing high-temperature carbonization on the super-crosslinked polymer, and performing temperature-controlled calcination; s5, in the steps, part of carbon atoms in the benzene ring are replaced by heteroatoms, the form and the structure of the super-crosslinked polymer are reserved, and the heteroatom-doped porous carbon nanotube is formed. According to the preparation method, the purity and quality of the material in the preparation process are effectively improved, and the obtained material has high specific surface area and excellent conductivity and mechanical strength, and shows a good application prospect in the field of electrochemistry.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material preparation, and particularly relates to a preparation method of heteroatom-doped hypercrosslinked polymer-based porous carbon nanotubes. BACKGROUND

[0002] In the past century, the significant increase in social productivity has led to a substantial increase in fossil energy consumption, which in turn has triggered the problem of global energy depletion. This dilemma has driven the demand for new energy storage devices, among which supercapacitors have attracted extensive attention from researchers due to their high power density, fast charging and discharging capability, and long cycle life. Supercapacitors are mainly composed of electrodes, separators, and electrolytes, and the electrode is the key factor determining its performance. Optimizing the morphology, surface chemistry, and electronic structure of the electrode material is one of the important methods to improve the energy storage performance of supercapacitors.

[0003] Hypercrosslinked polymers (HCPs) are a kind of advanced porous polymer materials with high porosity and excellent physical and chemical stability. They can be easily synthesized by using a one-step Friedel-Crafts polymerization reaction with inexpensive catalysts and monomers, avoiding the use of noble metal catalysts and monomers with specific polymerization groups, thus realizing low-cost and scalable HCPs synthesis. Through the selection of monomers and optimization of reaction conditions, HCPs can be customized into one-dimensional tubular structures of polymers, which can be customized into nanospheres, nanotubes, nanosheets, etc. The hypercrosslinked weaving structure of HCPs can prevent the collapse of pores during the subsequent carbonization process, thereby forming hypercrosslinked polymer-based porous carbon nanotubes. The one-dimensional tubular characteristics of the electrode have high conductivity, and the high surface area of the electrode provides abundant active sites, promoting charge transfer and ion transport. In addition, heteroatom-doped carbon-based electrode materials can produce some defects, further enhancing their electrochemical activity. SUMMARY

[0004] In view of the deficiencies in the prior art, the present application aims to provide a preparation method of heteroatom-doped hypercrosslinked polymer-based porous carbon nanotubes, which effectively improves the purity and quality of the material during the preparation process, and the obtained material has high specific surface area, excellent electrical conductivity and mechanical strength, and good application prospect in the field of electrochemistry. In order to achieve the above-mentioned purposes and other advantages according to the present application, a preparation method of heteroatom-doped hypercrosslinked polymer-based porous carbon nanotubes is provided, comprising:

[0005] S1, selecting a functional aromatic compound as a monomer to be dissolved in an organic solvent, connecting a reaction device to a vacuum pump to a vacuum state, then introducing an inert gas, and adding a required heteroatom dopant under an inert atmosphere;

[0006] S2, a Lewis acid catalyst is added to perform a self-crosslinking Friedel-Crafts reaction, and the entire reaction process is in inert gas protection;

[0007] Micro pump: used to accurately control the delivery rate of FeCl3 to ensure that the experimental requirements are met.

[0008] Closed delivery system: a closed device must be used to ensure that FeCl3 is safely and leak-free delivered to the reaction system; the inner walls of the pipes and containers must be made of anti-adhesion coating materials to completely avoid the adhesion of FeCl3 during transportation.

[0009] Ultrasonic assisted transmission technology: during the delivery process, the outer wall of the pipeline or reactor must be equipped with ultrasonic vibration devices to effectively reduce the adhesion of FeCl3 to the inner wall of the equipment, ensuring that it does not accumulate on the surface of the pipeline or reactor, thereby ensuring the continuity and efficiency of the transmission.

[0010] S3, the product produced in the above step is washed with ethanol and acetone, purified in a Soxhlet extractor, and then dried in a vacuum drying oven to prepare hypercrosslinked polymers (HCPs);

[0011] S4, the synthesized hypercrosslinked polymer is carbonized at high temperature and calcined in a tube furnace, adjusting the heating rate and controlling the calcination temperature.

[0012] S5, in the above step, one carbon atom in the benzene ring is replaced by a heteroatom, and the morphology and structure of the hypercrosslinked polymer are retained, forming a porous carbon nanotube with heteroatom doping.

[0013] Specifically:

[0014] Monomer dissolution: 3-8 mmol of monomer (such as any one of 1,4-benzenedimethanol, hydroquinone, 1,3,5-benzenetriol, 1,5-naphthalenedimethanol, 1,2,4-benzenetriol, 2,6-naphthalenedimethanol functionalized aromatic compounds) is dissolved in 30-80 mL of an organic solvent, such as any one of chloroform, 1,2-dichloroethane, dichloromethane.

[0015] Vacuum treatment and nitrogen protection: the above solution is subjected to vacuum treatment, one side is connected to a vacuum pump through a vacuum tube, and the other side is connected to a nitrogen cylinder. After reaching a vacuum state, nitrogen is introduced to ensure that the experiment is carried out in a nitrogen atmosphere, ensuring the safety of the experiment and the influence of environmental factors on the reaction.

[0016] Dopant addition: under a nitrogen atmosphere, 1.5-4.0 mmol of any one or more dopants, such as pyrrole, indole, phosphoric acid, phosphorus trioxide, thiophene, thiazole, boric acid, sodium borohydride, is added to the solution of step (2) through a needle tube.

[0017] Add Lewis acid and heat to react: add 6 mmol to 16 mmol of Lewis acid anhydrous ferric chloride (FeCl3) to the solution obtained in step (3), immerse the reaction bottle in silicone oil and heat to ensure that the reaction temperature is 60°C to 120°C, and stir the reaction for 12h to 48h.

[0018] Washing and filtering the crude product: The crude product obtained in step (4) is thoroughly washed with ethanol and acetone, and vacuum filtered through a vacuum filtration device until the filtrate becomes colorless and transparent.

[0019] Purification and drying: The product obtained in step (5) was purified in ethanol by Soxhlet extraction for 12 h to 24 h to remove all residual catalyst and monomers, and then placed in a vacuum oven at 40 ° C to 80 ° C for 12 h to 24 h to obtain a gray-black powder.

[0020] Calcination: The gray-black powder obtained in step (6) is placed in a tubular furnace and calcined for 2 h to 4 h at a calcination temperature of 700° C. to 900° C. at a heating rate of 5° C. / min to 15° C. / min, ultimately obtaining single heteroatom-doped or multi-heteroatom-co-doped hypercrosslinked polymer-based porous carbon nanotubes.

[0021] Compared with existing technologies, this invention offers the following advantages: by conducting the reaction under a nitrogen atmosphere, the effects of oxygen in the air on the reaction are effectively avoided; a specific reaction apparatus allows for effective control of the amount of Lewis acid used as a catalyst, and by controlling the temperature and time, the morphology can be effectively manipulated; and finally, high-temperature calcination yields high-performance doped hyper-crosslinked polymer-based porous carbon nanotubes. This method offers advantages such as ease of operation, mild reaction conditions, and high product purity, improving the performance of the material as an electrode material and making it suitable for large-scale production applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Scanning electron microscope and transmission electron microscope images of porous carbon nanotubes doped with a single element according to the method for preparing heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes of the present invention;

[0023] Figure 2 Scanning electron microscope and transmission electron microscope images of porous carbon nanotubes co-doped with two elements according to the preparation method of heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes of the present invention;

[0024] Figure 3 Scanning electron microscope and transmission electron microscope images of porous carbon nanotubes co-doped with three elements according to the preparation method of heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes of the present invention;

[0025] Figure 4X-ray diffraction pattern of the method for preparing the heteroatom-doped super-crosslinked polymer-based porous carbon nanotube according to the present application;

[0026] Figure 5 Single-element-doped porous carbon nanotube charge-discharge curve diagram of the method for preparing the heteroatom-doped super-crosslinked polymer-based porous carbon nanotube according to the present application;

[0027] Figure 6 Two-element co-doped porous carbon nanotube charge-discharge curve diagram of the method for preparing the heteroatom-doped super-crosslinked polymer-based porous carbon nanotube according to the present application;

[0028] Figure 7 Three-element co-doped porous carbon nanotube charge-discharge curve diagram of the method for preparing the heteroatom-doped super-crosslinked polymer-based porous carbon nanotube according to the present application;

[0029] Figure 8 Lewis acid adding device diagram of the method for preparing the heteroatom-doped super-crosslinked polymer-based porous carbon nanotube according to the present application. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be apparently and completely described below with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0031] A method for preparing a heteroatom-doped super-crosslinked polymer-based porous carbon nanotube, comprising the following steps:

[0032] (1) 3mmol-8mmol of monomers, which are any one of 1,4-benzene dimethanol, hydroquinone, 1,3,5-benzene tri-methanol, 1,5-naphthalene dimethanol, 1,2,4-benzene tri-methanol, and 2,6-naphthalene dimethanol, are placed in a three-necked flask reactor, and are added into 30mL-80mL of an organic solvent, which is any one of chloroform, 1,2-dichloroethane, and dichloromethane, by using a syringe, and then a piston is used to block the middle neck, and the reactor is placed on a magnetic stirrer, and the rotation speed is set to 300r / min-600r / min, so that the monomers are fully dissolved in the organic solvent;

[0033] (2) The solution of step (1) is subjected to vacuum treatment, one side neck is inserted into a vacuum tube connected to a vacuum pump, and the vacuum pump is used to extract air to achieve a vacuum state, ensuring that the inner cavity is free of residual gas, and the other side is connected to a nitrogen cylinder, and high-purity nitrogen is slowly introduced for step-by-step gas replacement until the oxygen content is reduced to below the ppb level. A temperature control system is added to the outer wall of the reactor to ensure the uniformity of the internal and external environment when the dopant is introduced;

[0034] (3) Under a nitrogen atmosphere, 1.5 mmol to 4.0 mmol of any one or more dopants, such as pyrrole, indole, phosphoric acid, phosphorus trioxide, thiophene, thiazole, boric acid, or sodium borohydride, are delivered by a micro pump, and the reactor is isolated from the outside environment by a series of high-precision sealing valves to ensure that the dopant does not come into contact with the outside environment during the entire transmission process. When introduced, the injection rate of the dopant is dynamically regulated by a precision flow meter and a gas mixing device to maintain a rate of 0.1 mmol / min to 0.5 mmol / min to avoid heterogeneous reactions caused by excessive local concentration. In addition, the reactor is equipped with a multi-point pressure monitoring and online component analysis system to monitor the changes in the atmosphere composition in real time during the reaction process, ensuring that the doping process is carried out in a constant nitrogen atmosphere;

[0035] (4) As shown in Figure 7 , the resulting solution of step (3) is quantitatively transferred to a water-free reaction bottle under nitrogen protection, and 6 mmol to 16 mmol of anhydrous ferric chloride (FeCl3) is accurately added. The outlet end of micro pump 1 is connected to a test tube, the bottom of the test tube is connected to a delivery pipeline, the end of the delivery pipeline away from the test tube is connected to a water-free reaction bottle, and the bottom of the water-free reaction bottle is placed with an ultrasonic device 3. In order to ensure the water-free state of anhydrous ferric chloride and the accuracy of the addition amount, prevent the residue of FeCl3 during the addition process, and combine ultrasonic assisted transmission technology with a closed delivery system through micro pump 1. First, micro pump 1 is used to accurately control the delivery rate of FeCl3. FeCl3 is safely and leak-free delivered to the reaction system through the closed delivery system. The inner wall of the pipeline and container in the closed delivery system can be coated with an anti-adhesion coating 2 to ensure that FeCl3 does not adhere to the inner wall of the pipeline and container during transportation. At the same time, ultrasonic assisted transmission technology is provided. During the delivery process, high-frequency vibration is generated by installing ultrasonic vibration device 3 on the pipeline or the outer wall of the reactor. The ultrasonic vibration effectively reduces the adhesion of FeCl3 to the inner wall of the container, preventing its accumulation on the surface of the pipeline or reactor;

[0036] (5) The reaction bottle of step (4) is immersed in a constant temperature silicone oil bath to ensure uniformity and stability of heat transfer. The temperature of the entire reaction system is slowly raised to 60-120°C, which is monitored in real time by a high-precision temperature probe and linked to a PID (proportional-integral-derivative) controller to ensure that the temperature error is controlled within ±0.1°C. The reaction system is continuously stirred by a magnetic stirrer for 12-48 h under constant temperature conditions of 60-120°C;

[0037] (6) The crude product obtained in step (5) is quickly transferred to a dry vacuum filtration device under the protection of anhydrous nitrogen atmosphere. In order to ensure the complete removal of residual impurities in the crude product, polar solvent ethanol and non-polar solvent acetone are alternately used for sufficient gradient washing. Washing and filtration are alternately performed until the color of the filtrate gradually changes from the initial yellow to colorless and transparent.

[0038] (7) The product obtained in step (6) is further purified by Soxhlet extraction. A Soxhlet extractor is used under the protection of anhydrous and anaerobic nitrogen, and high-purity ethanol is selected as the extraction solvent. The product is purified in ethanol for 12-24 h to remove all residual catalysts and monomers, and then placed in a vacuum oven at 40-80°C for 12-24 h to obtain a gray-black powder.

[0039] (8) The product obtained in step (7) is transferred to a high-temperature tube furnace for calcination. The temperature control system slowly heats the sample to 700-900°C at an accurate heating rate of 5-15°C / min. When the temperature rises to 700-900°C, the sample is calcined under this constant temperature condition for 2-4 h. During the calcination process, the temperature uniformity in the tube furnace is monitored in real time by a thermocouple to ensure that the temperature fluctuation of each part of the furnace tube does not exceed ±1°C, thereby avoiding local overheating or incomplete calcination of the sample. Finally, N atom-doped porous carbon nanotubes are obtained.

[0040] (9) The porous carbon nanotubes, conductive carbon black and polytetrafluoroethylene obtained in step (8) are mixed in a ratio of 8:1:1 in anhydrous ethanol to form a slurry, which is then coated on a nickel mesh to prepare a working electrode. The weight of the active material in each working electrode is about 1-3 mg.

[0041] (10) The working electrode in step (9), a mercury / mercury oxide electrode as a reference electrode, a platinum sheet as a counter electrode and 6M KOH as an electrolyte form a three-electrode system, and the electrochemical performance of the electrode is tested by charge-discharge method.

[0042] Example 1

[0043] Single heteroatom doping:

[0044] Preparation of N atom-doped hypercrosslinked nanotubes:

[0045] (1) Put 3 mmol of hydroquinone in a three-necked flask reactor, add 30 mL of 1,2 dichloromethane by pipette, and then block the middle neck with a piston and place it on a magnetic stirrer with a speed of 450 r / min to make the hydroquinone fully dissolved in 1,2 dichloromethane;

[0046] (2) The solution of step (1) is subjected to vacuum treatment, one side of the neck is inserted into a vacuum tube connected to a vacuum pump, and the vacuum pump is used to extract air to achieve a vacuum state, ensuring that there is no residual gas in the cavity, and the other side of the air pipe is connected to a nitrogen cylinder, and high-purity nitrogen is slowly introduced for step-by-step gas replacement until the oxygen content is reduced to below the ppb level. A temperature control system is added to the outer wall of the reactor to ensure the uniformity of the internal and external environment when the dopant is introduced;

[0047] (3) Under a nitrogen atmosphere, 1.5 mmol of N atom dopant pyrrole is delivered by a micro pump in step (2), and is isolated from the reactor by a series of high-precision sealing valves to ensure that the dopant does not come into contact with the external environment during the entire transmission process. When introduced, the injection rate of the dopant is dynamically controlled by a precision flowmeter and a gas mixing device to maintain at 0.1 mmol / min to avoid heterogeneous reactions caused by excessive local concentration. In addition, the reactor is equipped with a multi-point pressure monitoring and online composition analysis system to monitor the changes in the atmosphere composition in real time during the reaction process to ensure that the doping process is carried out in a constant nitrogen atmosphere;

[0048] (4) The resulting solution of step (3) is quantitatively transferred to an anhydrous reaction bottle under nitrogen protection, and 6 mmol of anhydrous Lewis acid ferric chloride (FeCl3) is accurately added to ensure that there is no water or oxygen interference during the reaction. To avoid any accidental moisture contamination, the ferric chloride needs to be pretreated under high vacuum conditions and added to the reaction system quickly in a nitrogen atmosphere;

[0049] (5) The reaction bottle of step (4) is immersed in a constant temperature silicone oil bath to ensure the uniformity and stability of heat transfer. The temperature of the entire reaction system is slowly raised to 60°C, and is monitored in real time by a high-precision temperature probe, and is linked with a PID (proportional-integral-derivative) controller to ensure that the temperature error is controlled within ±0.1°C

[0050] Under the condition of constant temperature at 60°C, the reaction system is continuously stirred by a magnetic stirrer for 24 h;

[0051] (6) The crude product obtained in step (5) was quickly transferred to a dry vacuum filtration device under the protection of anhydrous nitrogen atmosphere. In order to ensure that the residual impurities in the crude product were completely removed, a polar solvent ethanol and a non-polar solvent acetone were alternately used for sufficient gradient washing. The washing and filtering operations were alternately performed until the color of the filtrate gradually changed from the initial yellow to colorless and transparent;

[0052] (7) The product obtained in step (6) was further purified by Soxhlet extraction. A Soxhlet extractor was used under the protection of anhydrous and oxygen-free nitrogen. High-purity ethanol was selected as the extraction solvent. The product was purified in ethanol for 12 h to remove all residual catalysts and monomers. Then it was placed in a vacuum oven at 80°C for 12 h to obtain a gray-black powder.

[0053] (8) The product obtained in step (7) was transferred to a high-temperature tube furnace for calcination. The temperature control system slowly heated the sample to 700°C at an accurate heating rate of 5°C / min. When the temperature rose to 700°C, the sample was calcined at this constant temperature for 2 hours. During the calcination process, the temperature uniformity in the tube furnace was monitored in real time by a thermocouple to ensure that the temperature fluctuation of each part of the furnace tube did not exceed ±1°C, thereby avoiding local overheating or incomplete calcination of the sample. Finally, N atom-doped porous carbon nanotubes were obtained.

[0054] (9) The porous carbon nanotubes, conductive carbon black and polytetrafluoroethylene obtained in step (8) were mixed in a ratio of 8:1:1 in anhydrous ethanol to form a slurry, which was then coated on a nickel mesh to prepare a working electrode. The weight of the active material in the working electrode was about 1 mg to 3 mg. Figure 4

[0055] Preparation of S atom-doped hypercrosslinked nanotubes:

[0056] (1) 4 mmol of 1,3,5-benzene tri-methanol was placed in a three-necked flask reactor. 40 mL of chloroform was added by a syringe. The middle neck was then blocked with a piston and placed on a magnetic stirrer with a rotation speed of 400 r / min to ensure that the monomer was fully dissolved in the organic solvent.

[0057] (2) The solution of step (1) was subjected to vacuum treatment. One side of the neck was connected to a vacuum pump through a vacuum tube to extract air and achieve a vacuum state. The other side was connected to a nitrogen cylinder for gradual gas replacement until the oxygen content was reduced to below the ppb level. A temperature control system was added to the outer wall of the reactor to ensure the uniformity of the internal and external environments during the introduction of the dopant.​

[0058] (3) The 3.0 mmol S atom dopant thiophene is delivered by a micro pump under a nitrogen atmosphere and isolated from the reactor by a series of high-precision sealing valves, ensuring that the dopant is not in contact with the external environment during the entire transfer process. When introduced, the injection rate of the dopant is dynamically regulated by a precision flow meter and gas mixing device to maintain a rate of 0.2 mmol / min to avoid heterogeneous reactions caused by excessive local concentration. In addition, the reactor is equipped with a multi-point pressure monitoring and online component analysis system to monitor the changes in the atmosphere composition in real time during the reaction process, ensuring that the doping process is carried out in a constant nitrogen atmosphere;

[0059] (4) The resulting solution from step (3) is quantitatively transferred to an anhydrous reaction bottle under nitrogen protection, and 10 mmol of anhydrous Lewis acid ferric chloride (FeCl3) is accurately added to ensure that there is no moisture or oxygen interference during the reaction. In order to avoid any accidental moisture contamination, the ferric chloride needs to be pretreated under high vacuum conditions and added to the reaction system quickly in a nitrogen atmosphere;

[0060] (5) The reaction bottle of step (4) is immersed in a constant temperature silicone oil bath to ensure uniformity and stability of heat transfer. The temperature of the entire reaction system is slowly raised to 80°C, which is monitored in real time by a high-precision temperature probe and linked to a PID (proportional-integral-derivative) controller to ensure that the temperature error is controlled within ±0.1°C

[0061] Under constant temperature conditions at 80°C, the reaction system is continuously stirred by a magnetic stirrer for 18 h;

[0062] (6) The crude product obtained in step (5) is quickly transferred to a dry vacuum filtration device under anhydrous nitrogen atmosphere protection. In order to ensure that the residual impurities in the crude product are completely removed, polar solvent ethanol and non-polar solvent acetone are alternately used for sufficient gradient washing. Washing and filtration operations are alternately performed until the color of the filtrate gradually changes from the initial yellow to colorless and transparent;

[0063] (7) The product obtained in step (6) is further purified by Soxhlet extraction. A Soxhlet extractor is used under anhydrous and oxygen-free nitrogen protection, high-purity ethanol is selected as the extraction solvent, and the product is purified in ethanol for 18 h to remove all residual catalysts and monomers. Then it is placed in a vacuum oven at 60°C for 18 h to obtain a gray-black powder;

[0064] (8) The product obtained in step (7) is quantitatively transferred to a high-temperature tube furnace for calcination. The temperature control system slowly heats the sample to 800°C at an accurate heating rate of 10°C / min. When the temperature rises to 800°C

[0065] After that, the sample is calcined under this constant temperature condition for 2h, and the temperature uniformity in the tube furnace is monitored in real time by a thermocouple during the calcination process, so as to ensure that the temperature fluctuation of each part of the furnace tube is not more than ±1℃, thereby avoiding local overheating or incomplete calcination of the sample, and finally obtaining S atom-doped porous carbon nanotubes;

[0066] (9) The porous carbon nanotubes, conductive carbon black and polytetrafluoroethylene obtained in step (8) are mixed in a ratio of 8:1:1 in anhydrous ethanol to form a slurry, which is then coated on a nickel mesh to prepare a working electrode, and the weight of the active material in each working electrode is about 1mg-3mg.

[0067] (10) The working electrode in step (9), a mercury / mercury oxide electrode as a reference electrode, a platinum sheet as a counter electrode and 6M KOH as an electrolyte are combined to form a three-electrode system, and the electrochemical performance of the electrode is tested by a charge-discharge method.

[0068] Example 2

[0069] Two kinds of heteroatom co-doping:

[0070] Preparation of N, S atom co-doped hypercrosslinked nanotubes:

[0071] (1) 6mmol of 1,5-naphthalene dimethanol is placed in a three-necked flask reactor, 60mL of organic solvent dichloromethane is added by a syringe, and then the middle neck is blocked with a piston and placed on a magnetic stirrer with a speed of 500r / min, so that the monomer is fully dissolved in the organic solvent;

[0072] (2) The solution of step (1) is subjected to vacuum treatment, one side neck is inserted into a vacuum tube connected to a vacuum pump, and the other side gas pipe is connected to a nitrogen cylinder, and high-purity nitrogen is slowly introduced for step-by-step gas replacement until the oxygen content is reduced to below ppb level, and a temperature control system is added to the outer wall of the reactor to ensure the uniformity of the internal and external environment when the dopant is introduced;

[0073] (3) Under a nitrogen atmosphere, 2.5mmol of N atom dopant indole and 2.5mmol of S atom dopant thiazole are delivered by a micro pump in step (2), and are isolated from the reactor by a series of high-precision sealing valves to ensure that the dopant does not contact the external environment during the entire transmission process. When introduced, the injection rate of the dopant is dynamically controlled by a precision flow meter and a gas mixing device to maintain at 0.5mmol / min to avoid heterogeneous reactions caused by local high concentration. In addition, the reactor is equipped with a multi-point pressure monitoring and online composition analysis system to monitor the change of the atmosphere composition in real time during the reaction process to ensure that the doping process is carried out in a constant nitrogen atmosphere;

[0074] (4) The resulting solution from step (3) was quantitatively transferred to a dry reaction flask under nitrogen protection, and 12 mmol of anhydrous Lewis acid ferric chloride (FeCl3) was accurately added to ensure that there was no interference of moisture or oxygen during the reaction. In order to avoid any accidental moisture contamination, the ferric chloride was pretreated under high vacuum conditions and quickly added to the reaction system in a nitrogen atmosphere;

[0075] (5) The reaction flask from step (4) was immersed in a constant temperature silicone oil bath to ensure uniformity and stability of heat transfer. The temperature of the entire reaction system was slowly raised to 100°C, which was monitored in real time by a high-precision temperature probe and linked to a PID (proportional-integral-derivative) controller to ensure that the temperature error was controlled within ±0.1°C

[0076] Under the condition of constant temperature at 100°C, the reaction system was continuously stirred by a magnetic stirrer for 24 h;

[0077] (6) The crude product obtained in step (5) was quickly transferred to a dry vacuum filtration device under the protection of anhydrous nitrogen atmosphere. In order to ensure that the residual impurities in the crude product were completely removed, polar solvent ethanol and non-polar solvent acetone were alternately used for sufficient gradient washing. Washing and filtration were alternately performed until the color of the filtrate gradually changed from the initial yellow to colorless and transparent;

[0078] (7) The product obtained in step (6) was further purified by Soxhlet extraction. A Soxhlet extractor was used under the protection of anhydrous and oxygen-free nitrogen, and high-purity ethanol was selected as the extraction solvent. The product was purified in ethanol for 18 h to remove all residual catalysts and monomers, and then placed in a vacuum oven at 80°C for 18 h to obtain a gray-black powder;

[0079] (8) The product obtained in step (7) was quantitatively transferred to a high-temperature tube furnace for calcination. The temperature control system slowly heated the sample to 800°C at an accurate heating rate of 10°C / min. When the temperature rose to 800°C

[0080] , the sample was calcined at this constant temperature for 2 h. During the calcination process, the temperature uniformity in the tube furnace was monitored in real time by a thermocouple to ensure that the temperature fluctuation of each part of the furnace tube was not more than ±1°C, thereby avoiding local overheating or incomplete calcination of the sample. Finally, N, S atom co-doped porous carbon nanotubes were obtained;

[0081] (9) The porous carbon nanotubes obtained in step (8), conductive carbon black and polytetrafluoroethylene were mixed in a ratio of 8:1:1 in anhydrous ethanol to form a slurry, which was then coated on a nickel mesh to prepare a working electrode. The weight of the active material in each working electrode was about 1 mg to 3 mg.

[0082] (10) The working electrode in step (9), a mercury / mercury oxide electrode as a reference electrode, a platinum sheet as a counter electrode and 6M KOH as an electrolyte constitute a three-electrode system to test the electrochemical performance of the electrode by charge-discharge method.

[0083] Preparation of S, P atom co-doped hypercrosslinked nanotubes:

[0084] (1) 4 mmol of 2,6-naphthalene glycol was placed in a three-necked flask reactor, 40 mL of organic solvent dichloromethane was added by a pipette, and then the middle neck was blocked with a piston and placed on a magnetic stirrer with a speed of 500 r / min to make the monomer fully dissolved in the organic solvent;

[0085] (2) The solution of step (1) was vacuum treated, one side of the neck was inserted into a vacuum tube connected to a vacuum pump to extract air to achieve a vacuum state, ensuring that there was no residual gas in the cavity, and the other side of the air pipe was connected to a nitrogen cylinder to slowly introduce high-purity nitrogen for step-by-step gas replacement until the oxygen content was reduced to below the ppb level. A temperature control system was added to the outer wall of the reactor to ensure the uniformity of the internal and external environment when the dopant was introduced;

[0086] (3) Under a nitrogen atmosphere, 1.5 mmol of S atom dopant thiazole and 1.5 mmol of P atom dopant phosphoric acid were delivered by a micro pump in step (2) and were isolated from the reactor by a series of high-precision sealing valves to ensure that the dopant did not contact the external environment during the entire transmission process. When introduced, the injection rate of the dopant was dynamically controlled by a precision flow meter and a gas mixing device to maintain at 0.3 mmol / min to avoid heterogeneous reactions caused by excessive local concentration. In addition, the reactor was equipped with a multi-point pressure monitoring and online composition analysis system to monitor the changes in the atmosphere composition in real time during the reaction process to ensure that the doping process was carried out in a constant nitrogen atmosphere;

[0087] (4) The resulting solution of step (3) was quantitatively transferred to an anhydrous reaction bottle under nitrogen protection, and 10 mmol of Lewis acid anhydrous ferric chloride (FeCl3) was accurately added to ensure that there was no water or oxygen interference during the reaction. To avoid any accidental water pollution, the ferric chloride was pretreated under high vacuum conditions and quickly added to the reaction system in a nitrogen atmosphere;

[0088] (5) The reaction bottle of step (4) was immersed in a constant temperature silicone oil bath to ensure the uniformity and stability of heat transfer. The temperature of the entire reaction system was slowly raised to 80℃, which was monitored in real time by a high-precision temperature probe and was linked to a PID (proportional-integral-derivative) controller to ensure that the temperature error was controlled within ±0.1℃

[0089] Inside, under the condition of constant temperature at 80℃, the reaction system is continuously stirred by a magnetic stirrer for 24h;

[0090] (6) The crude product obtained in step (5) is quickly transferred to a dry vacuum filtration device under the protection of anhydrous nitrogen atmosphere. In order to ensure the complete removal of residual impurities in the crude product, a polar solvent ethanol and a non-polar solvent acetone are alternately used for sufficient gradient washing. The washing and filtering operations are alternately performed until the color of the filtrate gradually changes from the initial yellow to colorless and transparent.

[0091] (7) The product obtained in step (6) is further purified by Soxhlet extraction method. A Soxhlet extractor is used under the protection of anhydrous and oxygen-free nitrogen atmosphere, high-purity ethanol is selected as the extraction solvent, the product is purified in ethanol for 18h to remove all residual catalysts and monomers, and then it is placed in a vacuum oven at 60℃ for 18h to obtain a gray-black powder.

[0092] (8) The product obtained in step (7) is transferred to a high-temperature tube furnace for calcination treatment. The temperature control system slowly heats the sample to 750℃ at an accurate heating rate of 10℃ / min. When the temperature rises to 750℃

[0093] , the sample is calcined at this constant temperature for 2h. During the calcination process, the temperature uniformity in the tube furnace is monitored in real time by a thermocouple, ensuring that the temperature fluctuation of each part of the furnace tube does not exceed ±1℃, thereby avoiding local overheating or incomplete calcination of the sample. Finally, S and P atom co-doped porous carbon nanotubes are obtained.

[0094] (9) The porous carbon nanotubes obtained in step (8), conductive carbon black and polytetrafluoroethylene are mixed in a ratio of 8:1:1 in anhydrous ethanol to form a slurry, which is then coated on a nickel mesh to prepare a working electrode. The weight of the active material in each working electrode is about 1mg-3mg.

[0095] (10) The working electrode in step (9), a mercury / mercury oxide electrode as a reference electrode, a platinum sheet as a counter electrode and 6M KOH as an electrolyte form a three-electrode system, and the electrochemical performance of the electrode is tested by charge-discharge method.

[0096] Example 3

[0097] Three kinds of heteroatom co-doping:

[0098] Preparation of N, S, P atom co-doped hypercrosslinked nanotubes:

[0099] (1) 5mmol of 1,2,4-benzene tricarbinol is placed in a three-necked flask reactor, 50mL of dichloromethane is added by a pipette, and then the middle neck is blocked with a piston and placed on a magnetic stirrer with a speed of 500r / min to make the monomer fully dissolve in the organic solvent;

[0100] (2) The solution of step (1) is subjected to vacuum treatment, one side neck is inserted into a vacuum tube connected to a vacuum pump, and the air is extracted to achieve a vacuum state using a vacuum pump to ensure that the inner cavity is free of residual gas, and the other side is connected to a nitrogen cylinder, and high-purity nitrogen is slowly introduced for step-by-step gas replacement until the oxygen content is reduced to below the ppb level. A temperature control system is added to the outer wall of the reactor to ensure the uniformity of the internal and external environments when the dopant is introduced;

[0101] (3) Under a nitrogen atmosphere, 2.0 mmol of N atom dopant pyrrole, S atom dopant thiazole, and P atom dopant phosphorus trioxide are delivered by a micro pump in step (2), and are isolated from the reactor by a series of high-precision sealing valves to ensure that the dopant does not come into contact with the external environment during the entire transmission process. When introduced, the injection rate of the dopant is dynamically regulated by a precision flowmeter and a gas mixing device to maintain at 0.2 mmol / min to avoid heterogeneous reactions caused by excessive local concentration. In addition, the reactor is equipped with a multi-point pressure monitoring and online component analysis system to monitor the changes in the atmosphere composition in real time during the reaction process to ensure that the doping process is carried out in a constant nitrogen atmosphere;

[0102] (4) The resulting solution of step (3) is quantitatively transferred to an anhydrous reaction bottle under nitrogen protection, and 12 mmol of Lewis acid anhydrous ferric chloride (FeCl3) is accurately added to ensure that there is no water or oxygen interference during the reaction. To avoid any accidental moisture contamination, the ferric chloride needs to be pretreated under high vacuum conditions and quickly added to the reaction system in a nitrogen atmosphere;

[0103] (5) The reaction bottle of step (4) is immersed in a constant temperature silicone oil bath to ensure the uniformity and stability of heat transfer. The temperature of the entire reaction system is slowly raised to 100°C, which is monitored in real time by a high-precision temperature probe and linked to a PID (Proportional-Integral-Derivative) controller to ensure that the temperature error is controlled within ±0.1°C

[0104] Under the condition of constant temperature at 100°C, the reaction system is continuously stirred by a magnetic stirrer for 48h;

[0105] (6) The crude product obtained in step (5) is quickly transferred to a dry vacuum filtration device under anhydrous nitrogen atmosphere protection. In order to ensure that the residual impurities in the crude product are completely removed, polar solvent ethanol and non-polar solvent acetone are alternately used for sufficient gradient washing, and the washing and filtering operations are alternately performed until the color of the filtrate gradually changes from the initial yellow to colorless and transparent;

[0106] (7) The product obtained in step (6) is further purified by Soxhlet extraction. A Soxhlet extractor is used under the protection of anhydrous and oxygen-free nitrogen, high-purity ethanol is selected as the extraction solvent, and the product is purified in ethanol for 16 h to remove all residual catalysts and monomers, and then placed in a vacuum oven at 40-80°C for 16 h to obtain a gray-black powder;

[0107] (8) The product obtained in step (6) is transferred to a high-temperature tube furnace for calcination. The temperature control system slowly heats the sample to 800°C at an accurate heating rate of 10°C / min. When the temperature rises to 800°C

[0108] , the sample is calcined at this constant temperature for 4 h. During the calcination process, the temperature uniformity in the tube furnace is monitored in real time by a thermocouple, ensuring that the temperature fluctuation of each part of the furnace tube does not exceed ±1°C, thereby avoiding local overheating or incomplete calcination of the sample. Finally, N, S, and P atom co-doped porous carbon nanotubes are obtained;

[0109] (9) The porous carbon nanotubes obtained in step (8), conductive carbon black, and polytetrafluoroethylene are mixed in a ratio of 8:1:1 in anhydrous ethanol to form a slurry, which is then coated on a nickel mesh to prepare a working electrode. The weight of the active material in each working electrode is about 1-3 mg.

[0110] (10) The working electrode in step (9), a mercury / mercury oxide electrode as a reference electrode, a platinum sheet as a counter electrode, and 6M KOH as an electrolyte form a three-electrode system, and the electrochemical performance of the electrode is tested by charge-discharge method.

[0111] Preparation of S, P, and B atom co-doped hypercrosslinked nanotubes:

[0112] (1) 6 mmol of 2,6-naphthalene glycol is placed in a three-necked flask reactor, 60 mL of 1,2-dichloroethane is added by a syringe, and the middle neck is then blocked with a piston and placed on a magnetic stirrer with a rotation speed of 600 r / min to ensure that the monomer is fully dissolved in the organic solvent;

[0113] (2) The solution in step (1) is vacuum treated. One side of the neck is connected to a vacuum pump through a vacuum tube to extract air to achieve a vacuum state, and the other side is connected to a nitrogen cylinder for gradual gas replacement until the oxygen content is reduced to below ppb level. A temperature control system is added to the outer wall of the reactor to ensure the uniformity of the internal and external environment when the dopant is introduced;

[0114] (3) Under the nitrogen atmosphere, 3.0 mmol of S atom dopant thiophene, P atom dopant phosphorus trioxide and B atom dopant boric acid are respectively delivered by a micro pump, and are isolated from the reactor by a series of high-precision sealing valves, to ensure that the dopant is not in contact with the external environment during the whole transmission process. When introduced, the injection rate of the dopant is dynamically adjusted by a precision flow meter and a gas mixing device to maintain at 0.5 mmol / min, so as to avoid heterogeneous reaction caused by too high local concentration. In addition, a multi-point pressure monitoring and online component analysis system is provided in the reactor to monitor the change of atmosphere composition in real time during the reaction process, so as to ensure that the doping process is carried out in a constant nitrogen atmosphere;

[0115] (4) The obtained solution in step (3) is quantitatively transferred to an anhydrous reaction bottle under the protection of nitrogen, and 12 mmol of Lewis acid anhydrous ferric chloride (FeCl3) is accurately added, so as to ensure that there is no water or oxygen interference in the reaction process. In order to avoid any accidental moisture pollution, the ferric chloride needs to be pretreated under high vacuum condition and quickly added to the reaction system in a nitrogen atmosphere;

[0116] (5) The reaction bottle in step (4) is immersed in a constant-temperature silicone oil bath to ensure the uniformity and stability of heat transfer. The temperature of the whole reaction system is slowly raised to 120°C, which is monitored in real time by a high-precision temperature probe and linked with a PID (proportion-integral-derivative) controller to ensure that the temperature error is controlled within ±0.1°C

[0117] Under the condition of constant temperature at 120°C, the reaction system is continuously stirred by a magnetic stirrer for 48 h;

[0118] (6) The crude product obtained in step (5) is quickly transferred to a dry vacuum filtration device under the protection of anhydrous nitrogen atmosphere. In order to ensure that the residual impurities in the crude product are completely removed, a polar solvent ethanol and a non-polar solvent acetone are alternately used for sufficient gradient washing, and the washing and filtering operations are alternately carried out until the color of the filtrate gradually changes from the initial yellow to colorless and transparent;

[0119] (7) The product obtained in step (6) is further purified by Soxhlet extraction method. A Soxhlet extractor is used under the protection of anhydrous and oxygen-free nitrogen, high-purity ethanol is selected as the extraction solvent, and the product is purified in ethanol for 18 h to remove all residual catalysts and monomers, and then is placed in a vacuum oven at 40°C for 18 h to obtain a gray-black powder;

[0120] (8) The product obtained in step (7) is quantitatively transferred to a high-temperature tube furnace for calcination treatment. The temperature control system slowly heats the sample to 850°C at an accurate heating rate of 10°C / min, and when the temperature rises to 850°C

[0121] After that, the sample is calcined under this constant temperature condition for 2-4 hours. During the calcination process, the temperature uniformity in the tube furnace is monitored in real time by a thermocouple, ensuring that the temperature fluctuation of each part of the furnace tube does not exceed ±1°C, thereby avoiding local overheating or incomplete calcination of the sample. Finally, S, P, and B atom co-doped porous carbon nanotubes are obtained.

[0122]

[0123] (9) The porous carbon nanotubes, conductive carbon black, and polytetrafluoroethylene obtained in step (8) are mixed in a ratio of 8:1:1 in anhydrous ethanol to form a slurry, which is then coated on a nickel mesh to prepare a working electrode. The weight of the active material in each working electrode is about 1-3 mg.

[0124] (10) The working electrode in step (9), a mercury / mercury oxide electrode as a reference electrode, a platinum sheet as a counter electrode, and 6M KOH as an electrolyte form a three-electrode system, and the electrochemical performance of the electrode is tested by charge-discharge method.

[0125] Summary

[0126] Figure left 1 is a scanning electron microscope (SEM) image of N atom-doped hypercrosslinked nanotubes

[0127] Description: This image shows the microstructure of the sample, with many branched or needle-like nanostructures visible and evenly distributed. This structure indicates that the material is composed of a one-dimensional nanostructure, such as nanotubes.

[0128] Analysis: Morphology: From the image, it can be seen that the sample exhibits a relatively complex nanostructure, with branched or needle-like structures evenly distributed throughout the field of view. Such morphology has a high specific surface area, which helps to improve the performance of the material in the fields of electrochemistry, electrocatalysis, etc. Size: From the scale, the diameter of these nanostructures is between tens of nanometers and hundreds of nanometers, and the length is relatively long. Such size characteristics give it an advantage in terms of electron conduction and ion diffusion. Application scenarios: This kind of material can be used in lithium ion batteries, supercapacitors, catalysts, etc., and has potential in improving the electrochemical reaction activity.

[0129] Figure right 1 is a transmission electron microscope (TEM) image of N atom-doped hypercrosslinked nanotubes

[0130] Description: This image shows a long, slender nanostructure with a uniform shape and smooth surface.

[0131] ​Analysis: Morphology: The nanostructure in the image is a single nanotube. Judging from its uniform shape and smooth surface, it is likely a single crystal material or a high-quality polycrystalline material, and its internal structure may be relatively simple. Size: Judging from the scale, the diameter of this nanostructure is at the nanometer level, the length is long, and the ductility is good. Such structures have important applications in materials science, especially in terms of conductivity and optical properties. Internal structure: If the image corresponds to a nanotube structure, then this nanotube has a hollow structure, which may have excellent ion conductivity in energy storage materials.

[0132] Figure 2 on the left is a scanning electron microscope (SEM) image analysis of super-crosslinked nanotubes co-doped with N and S atoms.

[0133] Description: This image shows the nanostructure of the sample, with Figure 1 Compared with the SEM images of the quartz crystals, the structure is more compact and complex, with features similar to dendrites or branches. These structures are intertwined, indicating that the material is packed in a denser manner.

[0134] Analysis: Morphology: Figure 1 Compared to the previous SEM image, the nanostructures in this image are denser, and the diameter of each branch or needle-like structure is slightly larger. Judging by the scale, these nanostructures are approximately several hundred nanometers in diameter, making them coarser than the structures in the previous image. Surface properties: The nanostructures in the image appear rougher, indicating more active sites on the material's surface, which helps improve its performance in catalytic or electrochemical reactions. Arrangement: These structures are intertwined and tightly packed, increasing the material's mechanical stability and conductivity.

[0135] Differences:

[0136] Compared to Figure 1 The SEM image shows that the nanostructure in the current image is more compact and complex, and the connection between the structures may be denser, indicating that the material may have higher electrical conductivity or mechanical strength.

[0137] Figure 2 on the right is a transmission electron microscope (TEM) image analysis of super-crosslinked nanotubes co-doped with N and S atoms.

[0138] Description: This figure shows a nanowire structure with Figure 1 Compared with the TEM image of MgCl2, the surface is slightly irregular, and the internal structure shows certain layered or interface characteristics.

[0139] Analysis: Morphology: Figure 1Compared with the TEM image of the nanowire, the surface of this nanowire is not as smooth as the former, showing a more complex internal structure, and even some defects or polycrystalline characteristics. Internal structure: From the image, it can be seen that the nanowire has layered or interface features, which indicates that the nanowire has a multilayer structure or some inhomogeneity has been generated during the preparation process. Figure 1 This may result in different electrical or mechanical properties compared to the TEM image. Size: The diameter is similar to the previous image and remains at the nanometer scale, but the actual surface area is larger due to surface irregularities.

[0140] Differences:

[0141] and Figure 1 Compared with the TEM image of , the nanowire surface in this image is irregular and there are internal interfaces, suggesting that the preparation conditions of the sample or the properties of the material itself may be different, which may have different effects on its application performance.

[0142] Figure 3 on the left is a scanning electron microscope (SEM) image analysis of super-crosslinked nanotubes co-doped with N, S, and P atoms.

[0143] Description: This figure shows a material with a dendritic or needle-like structure, Figure 1 、 2 Compared with the SEM images of 3D images, these structures appear to be more ordered, and the surface of each nanostructure appears to be smoother.

[0144] Analysis: Morphology: Compared to Figure 1 、 2 The SEM image shows that the nanostructures are more slender, with smoother surfaces and more uniform distribution, indicating that the morphology of the material is more regular. Figure 1 、 2 The structure in the SEM image is more dispersed, indicating that the material has a higher specific surface area, which is beneficial for improving the activity in catalysis or electrochemical reactions. Surface characteristics: The smooth surface nanostructure means that the crystal growth of the material is more uniform under the synthesis conditions of multiple heteroatom co-doping.

[0145] Differences:

[0146] and Figure 1 、 2 Compared with the SEM image of the nanostructure, this image shows that the nanostructure is more slender, smoother and more orderly, which means that the material has better physical properties, such as higher mechanical strength or better conductivity.

[0147] Figure 3 on the right is a transmission electron microscope (TEM) image analysis of super-crosslinked nanotubes co-doped with N, S, and P atoms.

[0148] Description: This image shows a nanoscale composite structure that exhibits more complex morphology, appearing more unique and diverse compared to the previous TEM images.

[0149] Analysis: Morphology: Compared to the single nanowire in Figure 1 , 2 TEM image, the nanostmcture shown here is composed of multiple substructures, with a surface that is not as smooth as in the previous images, showing more complexity in morphology. Internal structure: The nanostmcture in this image appears to exhibit multiple layers or interfaces, indicating that the material underwent different growth stages or has a polycrystalline nature during synthesis, which can affect its electrical and mechanical properties. Size: Although the nanostmcture is still on the nanoscale, its complex morphology can significantly increase the surface area, which can positively impact the material's performance in electrochemical or catalytic applications.

[0150] Difference:

[0151] Compared to the TEM images of Figure 1 , 2 This image shows a complex nanostmcture, indicating that the material may have undergone different processes during growth, resulting in a multi-interface or multi-layered structure. This complexity can lead to different material properties, such as higher specific surface area, better catalytic activity, or different mechanical strength.

[0152] Figure 4 X-ray diffraction pattern of the preparation method of heteroatom-doped hypercrosslinked polymer-based porous carbon nanotubes according to the present invention:

[0153] HCP-1 is single heteroatom doping, HCP-2 is two heteroatom co-doping, and HCP-3 is three heteroatom co-doping. There are no obvious sharp peaks in the pattern, which usually means that the sample can be amorphous or have low crystallinity. For hypercrosslinked polymers, this is due to their highly crosslinked structure, proving the success of the preparation of heteroatom-doped hypercrosslinked polymers. The diffraction intensities of different samples are different, which is related to their chemical composition, crosslinking density, or polymer chain arrangement. The intensity of HCP-2 with two heteroatom co-doping is the lowest, which may indicate that it has the lowest crystallinity or the highest amorphous property.

[0154] In combination with Figure 5 , Example 6, discharge performance comparison:

[0155]

[0156] As shown in the table, Example 1 is single heteroatom doping, Example 2 is two heteroatom co-doping, and Example 3 is three heteroatom co-doping. The heteroatom-doped hypercrosslinked polymer-based porous carbon nanotubes prepared in the three examples all have higher specific capacitance than common daily supercapacitors, and the three heteroatom co-doped hypercrosslinked polymer-based porous carbon nanotubes have the best specific capacitance performance.

[0157] The number of devices and the scale of processing illustrated herein are intended to simplify the description of the present application and are not necessarily the actual number of devices and the scale of processing used in the implementation of the present application. Applications, modifications and variations of the present application, apparent to those skilled in the art, are intended to be covered by the following claims.

[0158] While the embodiments of the application have been disclosed as above, it is not limited to the applications and embodiments set forth in the specification and drawings, but can be applied to various fields suitable for the application, and additional modifications can be easily made by those skilled in the art, and therefore the application is not limited to the specific details and the figures shown and described herein.

Claims

1. A method and a reaction device for preparing heteroatom-doped hypercrosslinked polymer-based porous carbon nanotubes, characterized in that: include: S1. Select a functionalized aromatic compound as a monomer and dissolve it in an organic solvent. Pump the reaction apparatus to a vacuum state using a vacuum pump, then introduce an inert gas, and add the desired heteroatom dopant under the inert atmosphere. S2, adding a Lewis acid catalyst to carry out a self-crosslinking Friedel-Crafts reaction, and the entire reaction process is under the protection of an inert gas; S3, the product produced in the above step is washed with ethanol and acetone, purified in a Soxhlet extractor, and then placed in a vacuum drying oven to prepare hyper-crosslinked polymers (HCPs); S4, carbonizing the synthesized hyper-crosslinked polymer at high temperature, placing it in a tubular furnace for calcination, adjusting the heating rate, and controlling the calcination temperature; S5. In the above steps, some carbon atoms in the benzene ring are replaced by heteroatoms, and the morphology and structure of the hyper-crosslinked polymer are retained to form porous carbon nanotubes doped with heteroatoms.

2. The method for preparing heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes according to claim 1, wherein: The molecular formula of the structural unit of the hyper-crosslinked polymer-based porous carbon nanotube is as follows:

3. The method for preparing heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes according to claim 1, wherein: The monomer in step S1 is a functionalized aromatic compound, and specifically the monomer is one of the functionalized aromatic compounds of 1,4-benzenedimethanol, hydroquinone, 1,3,5-benzenetrimethanol, 1,5-naphthalene dimethanol, 1,2,4-benzenetrimethanol, and 2,6-naphthalene dimethanol.

4. The method for preparing heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes according to claim 1, wherein: The heteroatom dopant in step S1 includes a dopant containing nitrogen heteroatom, a dopant containing phosphorus heteroatom, a dopant containing sulfur heteroatom and a dopant containing boron heteroatom; The nitrogen-containing heteroatom dopant is: pyrrole, indole, carbazole, aniline, pyridine or 4,4'-bipyridine; The dopant containing phosphorus heteroatom is: phosphoric acid, phosphorus trioxide, triphenylphosphine or triphenyl phosphate; The sulfur-containing heteroatom doping agent is: thiophene, thiazole, thiophene-2-carboxaldehyde, thioglycolic acid, thiocarbamate or dibenzothiophene; The dopant containing a boron heteroatom is: boric acid, sodium borohydride, boron trifluoride, triethylboron, diborane, trimethylboron or potassium tetrafluoroborate; The heteroatom dopant is one or more of the above-mentioned heteroatom dopants and is used to prepare porous carbon nanotubes.

5. The preparation apparatus for heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes as described in claim 1 is as follows: the solution obtained in step S2 must be quantitatively transferred to an anhydrous reaction bottle under nitrogen protection, and 6 mmol to 16 mmol of Lewis acid anhydrous ferric chloride (FeCl3) must be accurately added in strict accordance with regulations; to ensure the anhydrous state of anhydrous ferric chloride and the accuracy of the addition amount, while eliminating FeCl3 residue during the addition process, a micropump and a closed delivery system combined with ultrasonic-assisted transmission technology must be used.

6. The method for preparing heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes according to claim 4, wherein: In step S4, the obtained hyper-crosslinked polymer is carbonized by high-temperature heat treatment, retaining the morphology and structure of the hyper-crosslinked polymer, and preparing a hyper-crosslinked polymer-based porous carbon nanotube doped with heteroatoms or co-doped with multiple heteroatoms.

7. The method for preparing heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes according to claim 5, wherein: In step S4, carbonization is performed at high temperature, and the carbon nanotubes are placed in a tube furnace and calcined for 2 to 4 hours. The calcination temperature is 700 to 900° C., and the heating rate is 5 to 15° C. / min to obtain heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes.

8. The method for preparing heteroatom-doped hyper-crosslinked polymer-based porous carbon nanotubes according to claim 1, wherein: The porous carbon nanotubes are successfully doped with a single heteroatom or co-doped with multiple heteroatoms; The electrodes made of doped porous carbon nanotubes exhibit excellent electrochemical performance in a three-electrode system with 6M KOH. At a current density of 0.5 A / g, the specific capacitance can reach a maximum of approximately 353 F / g.

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