A modified bamboo-derived porous carbon electrode material, its preparation method and application

Abstract

This invention discloses a modified bamboo-derived porous carbon electrode material, its preparation method, and its application, belonging to the field of supercapacitor technology. The preparation method of the modified bamboo-derived porous carbon electrode material includes the following steps: mixing bamboo powder with MoS2, adding an iron salt solution for hydrothermal carbonization to obtain hydrothermal carbon; activating the hydrothermal carbon with an alkali to obtain an activated product; and purifying the activated product to obtain the modified bamboo-derived porous carbon electrode material. This invention uses bamboo powder as a biomass raw material and, through the synergistic effect of MoS2 and iron salts, simultaneously optimizes the carbon framework pore structure, regulates MoS2 defects, and introduces Fe-based pseudocapacitive centers, thereby producing an electrode material with high specific surface area, abundant active sites, and excellent electrochemical performance.

Description

Technical Field

[0001] This invention relates to the field of supercapacitor technology, specifically to a modified bamboo-derived porous carbon electrode material, its preparation method, and its application. Background Technology

[0002] With the acceleration of the global energy transition, the demand for high-performance and environmentally friendly energy storage materials is becoming increasingly urgent. Supercapacitors, as energy storage devices with high power density and long cycle life, have broad application prospects in portable electronic devices, hybrid vehicles, and other fields.

[0003] Electrode materials are a core factor determining the performance of supercapacitors. Biomass-derived carbon (BDC) is an ideal candidate for supercapacitor electrode materials due to its advantages such as renewability, low cost, and tunable pore structure. However, electrode materials made from traditional biomass-derived carbon and MoS2-modified biomass-derived carbon have many drawbacks. Adding MoS2 alone results in low intrinsic conductivity, and direct composite formation increases the internal resistance of the material, affecting rate performance. MoS2 is prone to stacking and agglomeration during the composite process, leading to a decrease in specific surface area, burying active sites, and easy detachment from the carbon substrate during charge and discharge, resulting in poor cycle stability. Existing studies mostly involve simple composite formation of MoS2 and carbon or single metal doping, lacking an integrated synergistic modification strategy that simultaneously regulates the carbon framework pore structure, MoS2 microstructure / valence state, and introduces a second active center. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing a modified bamboo-derived porous carbon electrode material to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for preparing a modified bamboo-derived porous carbon electrode material includes the following steps:

[0007] Bamboo powder was mixed with MoS2 and then an iron salt solution was added for hydrothermal carbonization to obtain hydrothermal carbon.

[0008] Hydrothermal carbon is activated with alkali to obtain the activated product;

[0009] The activated product was purified to obtain a modified bamboo-derived porous carbon electrode material.

[0010] Furthermore, the mass ratio of the bamboo powder to MoS2 is 1:(0.1-0.3).

[0011] Furthermore, the mass-to-volume ratio of the bamboo powder to the iron salt solution is 1g:(10-15)mL; the concentration of the iron salt solution is 0.5-1.5M.

[0012] Furthermore, the iron salt solution is an FeCl3 solution.

[0013] Furthermore, the temperature of the hydrothermal carbonization is 170-190℃.

[0014] Furthermore, the activation treatment method is as follows:

[0015] Hydrothermal charcoal and alkali were mixed in a mass ratio of 1:(1-4), deionized water was added for impregnation, and then dried to obtain a dried mixture.

[0016] The dried mixture is heated to 700-900℃ and kept at that temperature for activation to obtain the activated product.

[0017] Furthermore, the base is KOH.

[0018] Furthermore, the purification process is as follows:

[0019] The activated product was washed with an acid solution, then washed with deionized water until neutral, and then dried to obtain the modified bamboo-derived porous carbon electrode material.

[0020] Another objective of this invention is to provide a modified bamboo-derived porous carbon electrode material prepared by the above-described method.

[0021] Another objective of this invention is to provide an application of the above-mentioned modified bamboo-derived porous carbon electrode material in the preparation of supercapacitors.

[0022] This invention provides a method for preparing modified bamboo-derived porous carbon electrode materials. Using bamboo powder as a biomass raw material, it optimizes the hydrothermal carbonization process by introducing MoS2 and iron salts as catalysts, overcoming the shortcomings of existing technologies, improving reaction efficiency, reducing production costs, minimizing equipment corrosion, and enhancing the quality of the final product. Through the synergistic effect of MoS2 and iron salts, this invention simultaneously optimizes the carbon framework pore structure, regulates MoS2 defects, and introduces Fe-based pseudocapacitive centers, thereby producing electrode materials with high specific surface area, abundant active sites, and excellent electrochemical performance. Furthermore, this invention expands the range of applicable raw materials, promoting more efficient and environmentally friendly high-value biochar production, and providing a novel technical solution for the efficient conversion and utilization of biomass energy. Attached Figure Description

[0023] Figure 1 The images show scanning electron microscope (SEM) images of the modified bamboo-derived porous carbon electrode materials prepared in Examples 1-3 and Comparative Example 1 of this invention (all scanned at a scale of 5µm); in the figures, A is Example 1, B is Example 2, C is Example 3, and D is Comparative Example 1.

[0024] Figure 2 The cyclic voltammetry (CV) curves are shown for the modified bamboo-derived porous carbon electrode materials prepared in Examples 1-3 and Comparative Example 1 of this invention.

[0025] Figure 3 The graphs show the constant current charge-discharge (GCD) curves of the modified bamboo-derived porous carbon electrode materials prepared in Examples 1-3 and Comparative Example 1 of this invention.

[0026] Figure 4 The images show electrochemical impedance spectroscopy (EIS) data of the modified bamboo-derived porous carbon electrode materials prepared in Examples 1-3 and Comparative Example 1 of this invention. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] In one embodiment of the present invention, a method for preparing a modified bamboo-derived porous carbon electrode material is provided, comprising the following steps:

[0029] S1. Raw material pretreatment: Pulverize the bamboo and pass it through a 40-80 mesh sieve to obtain bamboo powder, and dry it at 80-100℃ for 6-18 hours for later use.

[0030] S2. Hydrothermal carbonization: Mix 4g of the above-mentioned bamboo powder with 0.4-1.2g of MoS2 powder evenly, and add 40-60mL of iron salt solution with a concentration of 0.5-1.5M (preferably 0.8-1.2M). After stirring evenly, transfer to a hydrothermal reactor and carry out hydrothermal carbonization reaction for 5-7h under a protective atmosphere such as nitrogen, with a gas flow rate of 50-70mL / min and a temperature of 170-190℃. After the reaction is completed, filter, wash with deionized water until the pH value of the filtrate is 6.8±0.2, and then dry at 80-100℃ for 6-18h to obtain hydrothermal carbon (denoted as BDPC).

[0031] S3. Activation treatment: The above hydrothermal carbon and alkali are mixed at a mass ratio of 1:(1-4), and sufficient deionized water is added for impregnation for 1-3 hours. After magnetic stirring at a rate of 150-200 rad / min for 0.5-1.5 hours, the mixture is dried at 80-100℃ for 6-18 hours to obtain a dried mixture. Then, the dried mixture is transferred to a quartz boat and placed in a tube furnace. Under a protective atmosphere such as nitrogen, the mixture is heated to 700-900℃ at a heating rate of 8-12℃ / min and held for 1-3 hours for activation. After that, it is naturally cooled to room temperature to obtain the activated product.

[0032] S4. Purification treatment: The activated product is washed with an acid solution of concentration of 0.5-1.5M, then washed with deionized water until the filtrate is neutral, and then dried at 80-100℃ for 6-18h to obtain the modified bamboo-derived porous carbon electrode material (denoted as BDPCx).

[0033] The preferred iron salt solution is FeCl3 solution, but other iron salts such as ferric nitrate can be used instead, and the method is not limited to this. The preferred alkali is KOH, but other alkaline substances such as NaOH can be used instead, and the method is not limited to this. The preferred acid solution is HCl solution, but other acidic substances such as nitric acid can be used instead, and the method is not limited to this.

[0034] In this embodiment of the invention, using bamboo powder as biomass raw material, an electrode material with high specific surface area, abundant active sites, and excellent electrochemical performance can be prepared through hydrothermal assisted FeCl3 / MoS2 synergistic modification combined with KOH high-temperature activation. FeCl3 acts as a pore-forming agent to construct a hierarchical porous structure with high specific surface area, and as a structure and valence state regulator to optimize the phase composition and defect structure of MoS2. Simultaneously, highly active Fe-based pseudocapacitive centers are introduced, achieving synergistic enhancement of multiple components. This embodiment of the invention solves the problems of limited electrochemical activity, insufficient conductivity, and poor cycle stability of traditional biomass-derived carbon. The preparation method provided has advantages such as simple process, low cost, and environmental friendliness. The prepared electrode material can be widely used in high-performance supercapacitors.

[0035] In another embodiment of the present invention, a supercapacitor is also provided, which includes a working electrode; the working electrode is made of the above-mentioned modified bamboo-derived porous carbon electrode material, and the specific preparation method includes the following steps:

[0036] The modified bamboo-derived porous carbon electrode material, conductive agent (such as acetylene black), and binder (such as polyvinylidene fluoride) are mixed in a mass ratio of (7-9):(0.5-1.5):(0.5-1.5). An appropriate amount of solvent (such as N-methyl-2-pyrrolidone) is added and the mixture is ultrasonically dispersed for 20-40 minutes to form a uniform slurry. The slurry is then uniformly coated onto a nickel foam substrate and dried in an oven at 85-95℃ for 6-18 hours to obtain a semi-finished product. Subsequently, the dried semi-finished product is pressed for 1-3 minutes under a pressure of 10-20 MPa using a tablet press to obtain the working electrode.

[0037] Example 1: This example provides a modified bamboo-derived porous carbon electrode material and its working electrode. The specific preparation method includes the following steps:

[0038] S1. Raw material pretreatment: The bamboo produced in Guangde, Anhui Province is crushed and passed through a 60-mesh sieve to obtain bamboo powder, which is then dried at 90℃ for 12 hours for later use.

[0039] S2. Hydrothermal carbonization: Mix 4g of the above-mentioned bamboo powder with 0.6g of MoS2 powder evenly, add 50mL of 1M FeCl3 solution, stir evenly, and transfer to a hydrothermal reactor. Under a nitrogen protective atmosphere, purge the hydrothermal reactor with nitrogen at a gas flow rate of 60mL / min to remove the air in the hydrothermal reactor. Then, raise the temperature to 180℃ at a heating rate of 10℃ / min and carry out the hydrothermal carbonization reaction for 6h. During the reaction, magnetic stirring is performed at a rate of 180rad / min. After the reaction is completed, filter, wash with deionized water until the pH value of the filtrate is 6.8, and then dry at 90℃ for 12h to obtain hydrothermal carbon (denoted as BDPC1).

[0040] S3. Activation treatment: Mix 2g of the above hydrothermal carbon with 4g of KOH, add 20mL of deionized water and impregnate for 2h, stir magnetically at a rate of 180rad / min for 1h, and then dry at 90℃ for 12h to obtain a dried mixture; then, transfer the dried mixture to a quartz boat and place it in a tube furnace, introduce nitrogen gas at a gas flow rate of 60mL / min, heat to 800℃ at a heating rate of 10℃ / min under nitrogen protective atmosphere and hold for 2h, and then cool naturally to room temperature to obtain the activated product.

[0041] S4. Purification treatment: Add 50 mL of 1 M HCl solution to the activated product and wash it. Stir for 30 min, filter, and then wash with deionized water until the filtrate is neutral. Then dry at 90℃ for 12 h to obtain the modified bamboo-derived porous carbon electrode material (denoted as BDPC1-2-800).

[0042] S5. The modified bamboo-derived porous carbon electrode material, acetylene black, and polyvinylidene fluoride were mixed in a mass ratio of 8:1:1, and an appropriate amount of N-methyl-2-pyrrolidone was added as a solvent. The mixture was ultrasonically dispersed for 30 minutes to form a uniform slurry. The slurry was then uniformly coated onto a 1×1 cm... 2 The working electrode is obtained by drying the nickel foam substrate in a 90°C oven for 12 hours, followed by pressing it at 15MPa pressure for 2 minutes using a tablet press.

[0043] S6. The above working electrodes are arranged into a three-electrode configuration and subjected to cyclic voltammetry (CV) at a scan rate of 20 mV, followed by constant current charge-discharge (GCD) at a current density of 1 A / g, within the range of 0.01 Hz to 10 mV. 4 Electrochemical impedance spectroscopy (EIS) tests were performed within a test frequency range of Hz.

[0044] Example 2: This example provides a modified bamboo-derived porous carbon electrode material and its working electrode. The specific preparation method includes the following steps:

[0045] S1. Raw material pretreatment: The bamboo produced in Guangde, Anhui Province is crushed and passed through a 60-mesh sieve to obtain bamboo powder, which is then dried at 90℃ for 12 hours for later use.

[0046] S2. Hydrothermal carbonization: 4g of the above-mentioned bamboo powder and 0.6g of MoS2 powder were mixed evenly, and 50mL of 0.5M FeCl3 solution was added. After stirring evenly, the mixture was transferred to a hydrothermal reactor. Under a nitrogen protective atmosphere, the hydrothermal reactor was purged with nitrogen at a gas flow rate of 60mL / min to remove the air from the hydrothermal reactor. Then, the temperature was increased to 180℃ at a heating rate of 10℃ / min for hydrothermal carbonization reaction for 6h. During the reaction, the mixture was magnetically stirred at a rate of 180rad / min. After the reaction was completed, the mixture was filtered, washed with deionized water until the pH of the filtrate was 6.8, and then dried at 90℃ for 12h to obtain hydrothermal carbon (denoted as BDPC0.5).

[0047] S3. Activation treatment: Mix 2g of the above hydrothermal carbon with 4g of KOH, add 20mL of deionized water and impregnate for 2h, stir magnetically at a rate of 180rad / min for 1h, and then dry at 90℃ for 12h to obtain a dried mixture; then, transfer the dried mixture to a quartz boat and place it in a tube furnace, introduce nitrogen gas at a gas flow rate of 60mL / min, heat to 800℃ at a heating rate of 10℃ / min under nitrogen protective atmosphere and hold for 2h, and then cool naturally to room temperature to obtain the activated product.

[0048] S4. Purification treatment: Add 50 mL of 1 M HCl solution to the activated product and wash it. Stir for 30 min, filter, and then wash with deionized water until the filtrate is neutral. Then dry at 90℃ for 12 h to obtain the modified bamboo-derived porous carbon electrode material (denoted as BDPC0.5-2-800).

[0049] S5. The modified bamboo-derived porous carbon electrode material, acetylene black, and polyvinylidene fluoride were mixed in a mass ratio of 8:1:1, and an appropriate amount of N-methyl-2-pyrrolidone was added as a solvent. The mixture was ultrasonically dispersed for 30 minutes to form a uniform slurry. The slurry was then uniformly coated onto a 1×1 cm... 2 The working electrode is obtained by drying the nickel foam substrate in a 90°C oven for 12 hours, followed by pressing it at 15MPa pressure for 2 minutes using a tablet press.

[0050] S6. The above working electrodes are arranged into a three-electrode configuration and subjected to cyclic voltammetry (CV) at a scan rate of 20 mV, followed by constant current charge-discharge (GCD) at a current density of 1 A / g, within the range of 0.01 Hz to 10 mV. 4 Electrochemical impedance spectroscopy (EIS) tests were performed within a test frequency range of Hz.

[0051] Example 3: This example provides a modified bamboo-derived porous carbon electrode material and its working electrode. The specific preparation method includes the following steps:

[0052] S1. Raw material pretreatment: The bamboo produced in Guangde, Anhui Province is crushed and passed through a 60-mesh sieve to obtain bamboo powder, which is then dried at 90℃ for 12 hours for later use.

[0053] S2. Hydrothermal carbonization: 4g of the above-mentioned bamboo powder and 0.6g of MoS2 powder were mixed evenly, and 50mL of 1.5M FeCl3 solution was added. After stirring evenly, the mixture was transferred to a hydrothermal reactor. Under a nitrogen protective atmosphere, the hydrothermal reactor was purged with nitrogen at a gas flow rate of 60mL / min to remove the air from the hydrothermal reactor. Then, the temperature was increased to 180℃ at a heating rate of 10℃ / min for hydrothermal carbonization reaction for 6h. During the reaction, magnetic stirring was performed at a rate of 180rad / min. After the reaction was completed, the mixture was filtered, washed with deionized water until the pH of the filtrate was 6.8, and then dried at 90℃ for 12h to obtain hydrothermal carbon (denoted as BDPC1.5).

[0054] S3. Activation treatment: Mix 2g of the above hydrothermal carbon with 4g of KOH, add 20mL of deionized water and impregnate for 2h, stir magnetically at a rate of 180rad / min for 1h, and then dry at 90℃ for 12h to obtain a dried mixture; then, transfer the dried mixture to a quartz boat and place it in a tube furnace, introduce nitrogen gas at a gas flow rate of 60mL / min, heat to 800℃ at a heating rate of 10℃ / min under nitrogen protective atmosphere and hold for 2h, and then cool naturally to room temperature to obtain the activated product.

[0055] S4. Purification treatment: Add 50 mL of 1 M HCl solution to the activated product and wash it. Stir for 30 min, filter, and then wash with deionized water until the filtrate is neutral. Then dry at 90℃ for 12 h to obtain the modified bamboo-derived porous carbon electrode material (denoted as BDPC1.5-2-800).

[0056] S5. The modified bamboo-derived porous carbon electrode material, acetylene black, and polyvinylidene fluoride were mixed in a mass ratio of 8:1:1, and an appropriate amount of N-methyl-2-pyrrolidone was added as a solvent. The mixture was ultrasonically dispersed for 30 minutes to form a uniform slurry. The slurry was then uniformly coated onto a 1×1 cm... 2 The working electrode is obtained by drying the nickel foam substrate in a 90°C oven for 12 hours, followed by pressing it at 15MPa pressure for 2 minutes using a tablet press.

[0057] S6. The above working electrodes are arranged into a three-electrode configuration and subjected to cyclic voltammetry (CV) at a scan rate of 20 mV, followed by constant current charge-discharge (GCD) at a current density of 1 A / g, within the range of 0.01 Hz to 10 mV. 4 Electrochemical impedance spectroscopy (EIS) tests were performed within a test frequency range of Hz.

[0058] Example 4: This example provides a modified bamboo-derived porous carbon electrode material and its working electrode. The specific preparation method includes the following steps:

[0059] S1. Raw material pretreatment: The bamboo produced in Guangde, Anhui Province is crushed and passed through a 40-mesh sieve to obtain bamboo powder, which is then dried at 80℃ for 18 hours for later use.

[0060] S2. Hydrothermal carbonization: Mix 4g of the above-mentioned bamboo powder with 0.4g of MoS2 powder evenly, and add 40mL of 1.2M FeCl3 solution. After stirring evenly, transfer to a hydrothermal reactor. Under a nitrogen protective atmosphere, purge the hydrothermal reactor with nitrogen at a gas flow rate of 50mL / min to remove the air in the hydrothermal reactor. Then, raise the temperature to 170℃ at a heating rate of 8℃ / min and carry out the hydrothermal carbonization reaction for 5h. During the reaction, magnetic stirring is performed at a rate of 150rad / min. After the reaction is completed, filter, wash with deionized water until the pH value of the filtrate is 6.6, and then dry at 80℃ for 18h to obtain hydrothermal carbon.

[0061] S3. Activation treatment: Mix 2g of the above hydrothermal carbon with 2g of KOH, add 15mL of deionized water and impregnate for 1h, stir magnetically at a rate of 150rad / min for 0.5h, and then dry at 80℃ for 18h to obtain a dried mixture; then, transfer the dried mixture to a quartz boat and place it in a tube furnace, introduce nitrogen gas at a gas flow rate of 50mL / min, heat to 700℃ at a heating rate of 8℃ / min under nitrogen protection atmosphere and hold for 1h, and then cool naturally to room temperature to obtain the activated product.

[0062] S4. Purification treatment: Add 40 mL of 0.5 M HCl solution to the activated product and wash it. Stir for 30 min, filter, and then wash with deionized water until the filtrate is neutral. Then dry at 80℃ for 18 h to obtain the modified bamboo-derived porous carbon electrode material.

[0063] S5. The modified bamboo-derived porous carbon electrode material, acetylene black, and polyvinylidene fluoride were mixed in a mass ratio of 7:1.5:1.5, and an appropriate amount of N-methyl-2-pyrrolidone was added as a solvent. The mixture was ultrasonically dispersed for 30 minutes to form a uniform slurry. The slurry was then uniformly coated onto a 1×1 cm... 2 The working electrode is obtained by drying the nickel foam substrate in an oven at 85°C for 18 hours, and then pressing it at 10MPa pressure for 1 minute using a tablet press.

[0064] Example 5: This example provides a modified bamboo-derived porous carbon electrode material and its working electrode. The specific preparation method includes the following steps:

[0065] S1. Raw material pretreatment: The bamboo produced in Guangde, Anhui Province is crushed and passed through an 80-mesh sieve to obtain bamboo powder, which is then dried at 100℃ for 6 hours for later use.

[0066] S2. Hydrothermal carbonization: Mix 4g of the above-mentioned bamboo powder with 1.2g of MoS2 powder evenly, and add 60mL of 0.8M FeCl3 solution. After stirring evenly, transfer to a hydrothermal reactor. Under a nitrogen protective atmosphere, purge the hydrothermal reactor with nitrogen at a gas flow rate of 70mL / min to remove the air in the hydrothermal reactor. Then, heat to 190℃ at a heating rate of 12℃ / min for hydrothermal carbonization reaction for 7h. During the reaction, magnetic stirring is performed at a rate of 200rad / min. After the reaction is completed, filter, wash with deionized water until the pH of the filtrate is 7, and then dry at 00℃ for 6h to obtain hydrothermal carbon.

[0067] S3. Activation treatment: Mix 2g of the above hydrothermal carbon with 8g of KOH, add 30mL of deionized water and impregnate for 3h, stir magnetically at a rate of 200rad / min for 1.5h, and then dry at 100℃ for 6h to obtain a dried mixture; then, transfer the dried mixture to a quartz boat and place it in a tube furnace, introduce nitrogen gas at a gas flow rate of 70mL / min, and heat to 900℃ at a heating rate of 12℃ / min under a nitrogen protective atmosphere for 3h activation, and then cool naturally to room temperature to obtain the activated product.

[0068] S4. Purification treatment: Add 50 mL of 1 M HCl solution to the activated product and wash it. Stir for 30 min, filter, and then wash with deionized water until the filtrate is neutral. Then dry at 100℃ for 6 h to obtain the modified bamboo-derived porous carbon electrode material.

[0069] S5. The modified bamboo-derived porous carbon electrode material, acetylene black, and polyvinylidene fluoride were mixed in a mass ratio of 9:0.5:0.5, and an appropriate amount of N-methyl-2-pyrrolidone was added as a solvent. The mixture was ultrasonically dispersed for 30 minutes to form a uniform slurry. The slurry was then uniformly coated onto a 1×1 cm... 2 The working electrode is obtained by drying the nickel foam substrate in a 95°C oven for 6 hours, followed by pressing it at 20MPa pressure for 3 minutes using a tablet press.

[0070] Comparative Example 1: This comparative example provides a modified bamboo-derived porous carbon electrode material without added FeCl3 and the working electrode prepared therefrom. The specific preparation method includes the following steps:

[0071] S1. Raw material pretreatment: The bamboo produced in Guangde, Anhui Province is crushed and passed through a 60-mesh sieve to obtain bamboo powder, which is then dried at 90℃ for 12 hours for later use.

[0072] S2. Hydrothermal carbonization: Mix 4g of the above-mentioned bamboo powder with 0.6g of MoS2 powder evenly, add 50mL of water, stir evenly, and transfer to a hydrothermal reactor. Under a nitrogen protective atmosphere, purge the hydrothermal reactor with nitrogen at a gas flow rate of 60mL / min to remove the air in the hydrothermal reactor. Then, heat to 180℃ at a heating rate of 10℃ / min for hydrothermal carbonization reaction for 6h. During the reaction, magnetic stirring is performed at a rate of 180rad / min. After the reaction is completed, filter, wash with deionized water until the pH of the filtrate is 6.8, and then dry at 90℃ for 12h to obtain hydrothermal carbon (denoted as BDPC).

[0073] S3. Activation treatment: Mix 2g of the above hydrothermal carbon with 4g of KOH, add 20mL of deionized water and impregnate for 2h, stir magnetically at a rate of 180rad / min for 1h, and then dry at 90℃ for 12h to obtain a dried mixture; then, transfer the dried mixture to a quartz boat and place it in a tube furnace, introduce nitrogen gas at a gas flow rate of 60mL / min, heat to 800℃ at a heating rate of 10℃ / min under nitrogen protective atmosphere and hold for 2h, and then cool naturally to room temperature to obtain the activated product.

[0074] S4. Purification treatment: Add 50 mL of 1 M HCl solution to the activated product and wash it. Stir for 30 min, filter, and then wash with deionized water until the filtrate is neutral. Then dry at 90℃ for 12 h to obtain the modified bamboo-derived porous carbon electrode material (denoted as BDPC-2-800).

[0075] S5. The modified bamboo-derived porous carbon electrode material, acetylene black, and polyvinylidene fluoride were mixed in a mass ratio of 8:1:1, and an appropriate amount of N-methyl-2-pyrrolidone was added as a solvent. The mixture was ultrasonically dispersed for 30 minutes to form a uniform slurry. The slurry was then uniformly coated onto a 1×1 cm... 2 The working electrode is obtained by drying the nickel foam substrate in a 90°C oven for 12 hours, followed by pressing it at 15MPa pressure for 2 minutes using a tablet press.

[0076] S6. The above working electrodes are arranged into a three-electrode configuration and subjected to cyclic voltammetry (CV) at a scan rate of 20 mV, followed by constant current charge-discharge (GCD) at a current density of 1 A / g, within the range of 0.01 Hz to 10 mV. 4 Electrochemical impedance spectroscopy (EIS) tests were performed within a test frequency range of Hz.

[0077] Performance Comparison: I. The modified bamboo-derived porous carbon electrode materials BDPC0.5-2-800, BDPC1-2-800, and BDPC1.5-2-800 prepared in Examples 1-3 above, as well as the modified bamboo-derived porous carbon electrode material BDPC-2-800 prepared in Comparative Example 1, were analyzed by scanning electron microscopy (SEM). The SEM images are shown below. Figure 1 As shown. According to Figure 1 It can be seen that, under the same hydrothermal temperature and activation conditions, the addition of FeCl3 significantly altered the microstructure of the modified bamboo-derived porous carbon. Compared with Comparative Example 1, the surface pore structure of the modified bamboo-derived porous carbon electrode material prepared in the embodiments of the present invention is more developed, and the pore connectivity is significantly improved.

[0078] Specifically, BDPC0.5-2-800 (Example 2) exhibits an irregular aggregated structure, with its surface composed of densely packed sheet-like / thin block-like structures stacked to form loose layered pores; BDPC1-2-800 (Example 1) forms a continuous sponge-like porous skeleton structure, without independent block-like aggregates, and is composed of interconnected pore walls forming a three-dimensional network / honeycomb structure, with pores distributed in a multi-level distribution of large pores containing small pores, and thin sheet-like units interleaved to form a large number of open voids; BDPC1.5-2-800 (Example 3) is a uniform and dense porous aggregated structure, with densely interconnected microporous networks formed between units, exhibiting a dense but porous characteristic. These phenomena indicate that the synergistic effect of FeCl3 and MoS2 promotes the oxidative etching and pore reconstruction reactions during hydrothermal carbonization and activation. The intensification of the reaction leads to an increase in the specific surface area and pore volume of porous carbon, and sufficient exposure of active sites. The differences in the microstructure of the three groups of samples are mainly related to the different concentrations of FeCl3. Among them, low concentration of FeCl3 (0.5M) mainly induces selective etching, forming a structure dominated by mesopores; a suitable concentration of FeCl3 (1M) induces intense oxidative etching, generating a micropore-mesopore hierarchical structure; and excessively high concentration of FeCl3 (1.5M) leads to pore wall collapse, merging of adjacent mesopores, and an increase in the proportion of micropores. In addition, the SEM image of Example 1 shows that it has both a loose feel and hollow features. This structure provides both a main channel for ion transport and sufficient adsorption sites, providing structural support for improving the rate performance and capacitance performance of the material, and providing a strong guarantee for the application of high-performance supercapacitor electrodes.

[0079] II. The CV curves of the modified bamboo-derived porous carbon electrode materials BDPC0.5-2-800, BDPC1-2-800, and BDPC1.5-2-800 prepared in Examples 1-3 above, and the modified bamboo-derived porous carbon electrode material BDPC-2-800 prepared in Comparative Example 1 are as follows: Figure 2 As shown, the GCD curves for constant current charge-discharge at a current density of 1 A / g are as follows: Figure 3As shown, in the range of 0.01Hz to 10 4 Electrochemical impedance spectroscopy test results within the test frequency range of Hz are as follows: Figure 4 As shown.

[0080] from Figure 2 The CV curves show that, at the same scan rate of 20 mV, the CV curve areas of Examples 1-3 are all larger than those of Comparative Example 1, especially the CV curve area of ​​Example 1, which is almost twice that of Comparative Example 1. These phenomena indicate that the synergistic effect of FeCl3 and MoS2 gives the electrode material good electrochemical properties. It should be noted that in the cyclic voltammetry curve of a supercapacitor, the current density reflects the magnitude of the charge and discharge current, the potential range corresponds to the operating voltage window, and the area enclosed by the curve corresponds to the specific capacitance of the supercapacitor (the larger the area, the higher the specific capacitance).

[0081] from Figure 3 As can be seen from the GCD curves, under the same current density, the charge-discharge times of Examples 1-3 are all longer than those of Comparative Example 1. The constant-current discharge curves show that Example 1 has a longer discharge time, corresponding to a higher actual specific capacity, further confirming its excellent energy storage performance; the specific capacitance data of Example 1 more directly demonstrates the synergistic effect, while the specific capacitance of Comparative Example 1 is only 236 F·g. -1 The specific capacitance of Example 1 after FeCl3 synergistic modification increased to 480 F·g. -1 It is significantly superior to the MoS2 / bamboo carbon system without FeCl3.

[0082] from Figure 4 The EIS data show that the impedance curve of Example 1 is closer to the origin, indicating that its charge transfer resistance is smaller and the electrochemical kinetics process is faster. The appropriate introduction of FeCl3 can tune the band structure of MoS2 and reduce its intrinsic resistance.

[0083] The test results of the above three complementary characterization techniques corroborate each other and form a closed loop, providing sufficient support for the excellent electrochemical performance of the FeCl3 / MoS2 synergistically modified bamboo-derived porous carbon electrode material: Cyclic voltammetry clearly reveals the synergistic energy storage mechanism of double-layer capacitance and pseudocapacitance in the material, and its regular quasi-rectangular curve and characteristic redox peak confirm the efficient coupling of the two types of capacitance; Electrochemical impedance spectroscopy further verifies the optimized interfacial charge transfer characteristics of the material, and the minimum charge transfer resistance and impedance response approaching that of an ideal capacitor reflect a significant improvement in charge transport efficiency.

[0084] In summary, the FeCl3 and MoS2 used in the embodiments of this invention are both widely available and inexpensive chemical raw materials, effectively reducing production costs and avoiding the strong corrosion problems of traditional strong acid and strong base catalysts on equipment, thus extending the service life of the reaction device. By controlling parameters such as FeCl3 concentration, the mass ratio of KOH to hydrothermal carbon, and activation temperature, the embodiments of this invention can precisely control the pore structure and chemical composition of the modified bamboo-derived porous carbon electrode material, adapting it to the performance requirements of different energy storage scenarios. Whether pursuing high specific capacitance or high cycle stability, efficient preparation can be achieved through process optimization, making the reaction process more flexible and adaptable. Furthermore, the multiple synergistic effects of FeCl3 (acting simultaneously as a pore-forming agent, a MoS2 defect regulator, and an Fe-based pseudocapacitive center introducer) significantly promote pore reconstruction, MoS2 phase optimization, and in-situ generation of Fe-based active sites in the modified bamboo-derived porous carbon electrode material, while inhibiting the stacking and agglomeration of MoS2, thus improving the structural stability of the electrode material.

[0085] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification.

Claims

1. A method for preparing a modified bamboo-derived porous carbon electrode material, characterized in that, Includes the following steps: Bamboo powder was mixed with MoS2 and then an iron salt solution was added for hydrothermal carbonization to obtain hydrothermal carbon. Hydrothermal carbon is activated with alkali to obtain the activated product; The activated product was purified to obtain a modified bamboo-derived porous carbon electrode material.

2. The method for preparing the modified bamboo-derived porous carbon electrode material according to claim 1, characterized in that, The mass ratio of bamboo powder to MoS2 is 1:(0.1-0.3).

3. The method for preparing the modified bamboo-derived porous carbon electrode material according to claim 1, characterized in that, The mass-to-volume ratio of the bamboo powder to the iron salt solution is 1g:(10-15)mL; the concentration of the iron salt solution is 0.5-1.5M.

4. The method for preparing the modified bamboo-derived porous carbon electrode material according to claim 1 or 3, characterized in that, The iron salt solution is an FeCl3 solution.

5. The method for preparing the modified bamboo-derived porous carbon electrode material according to claim 1, characterized in that, The hydrothermal carbonization temperature is 170-190℃.

6. The method for preparing the modified bamboo-derived porous carbon electrode material according to claim 1, characterized in that, The activation treatment method is as follows: Hydrothermal charcoal and alkali were mixed in a mass ratio of 1:(1-4), and deionized water was added for impregnation. The mixture was then dried to obtain the dried mixture. The dried mixture is heated to 700-900℃ and kept at that temperature for activation to obtain the activated product.

7. The method for preparing the modified bamboo-derived porous carbon electrode material according to claim 1 or 6, characterized in that, The alkali is KOH.

8. The method for preparing the modified bamboo-derived porous carbon electrode material according to claim 1, characterized in that, The purification process is as follows: The activated product was washed with an acid solution, then washed with deionized water until neutral, and then dried to obtain the modified bamboo-derived porous carbon electrode material.

9. A modified bamboo-derived porous carbon electrode material prepared by any one of the preparation methods described in claims 1-8.

10. The application of the modified bamboo-derived porous carbon electrode material as described in claim 9 in the preparation of supercapacitors.

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