Preparation method of fe2o3 / bamboo leaf carbon composite lithium ion battery negative electrode material

Abstract

The application provides a preparation method of Fe2O3 / bamboo leaf carbon negative electrode material, which comprises the following steps: (1) cleaning and drying bamboo leaves; (2) calcining the bamboo leaves in a nitrogen atmosphere at 800-1200 DEG C for 2-5 hours; (3) ball milling the calcined sample for 24-72 hours to obtain bamboo leaf carbon powder, treating the bamboo leaf carbon powder with HF solution, and finally rinsing the bamboo leaf carbon powder with deionized water and anhydrous ethanol and drying to obtain bamboo leaf carbon; (4) using Fe(NO3)3.9H2O as an iron source, an intermediate is prepared by a hydrothermal method; (5) calcining the intermediate in air to obtain Fe2O3; (6) using a mixture of anhydrous ethanol and N,N-dimethylformamide (DMF) as a solvent, Fe2O3 / bamboo leaf carbon composite material is obtained by mixing Fe2O3 and bamboo leaf carbon through a solvothermal method. The application carbon-dopes nano Fe2O3 active substance, weakens the phenomenon that the sample morphology is destroyed during use, and improves the conductivity of the electrode material. Bamboo grows rapidly, and bamboo resources are abundant in China; therefore, it is very economical to use discarded bamboo leaves as a carbon source, and therefore, Fe2O3 / bamboo leaf carbon has high practical value as a lithium ion battery negative electrode.

Description

Technical Field

[0001] This invention belongs to the field of next-generation energy storage, and specifically relates to a method for preparing Fe2O3 / bamboo leaf carbon composite material for lithium-ion battery anode materials. Background Technology

[0002] With the increasing market share of electric vehicles and new energy storage, lithium-ion batteries have gained attention due to their advantages such as high voltage, large specific capacity, long cycle life, and good safety performance. Traditional lithium-ion battery anode materials are graphite, but its theoretical specific capacity (372 mAh·g⁻¹) is too low to meet the growing demand. Exploring high-capacity lithium-ion battery anode materials is one of the urgent technological challenges facing the industry today.

[0003] Fe2O3, with its high specific capacity (1007 mAh / g), abundant reserves, and non-toxicity, is currently a hot research topic in anode materials. However, Fe2O3 exhibits poor conductivity as a lithium-ion battery anode material, and its volume undergoes drastic changes during lithium insertion / extraction, leading to structural collapse and subsequent pulverization and detachment from the current collector, thus reducing its electrochemical performance. Currently, two main methods are employed to overcome these drawbacks: one is to nanoscale Fe2O3 particles. Nanostructures can reduce the strain of iron oxide particles during lithium insertion / extraction, increasing their resistance to pulverization and shortening the lithium insertion / extraction path, thereby improving electrochemical performance. The other method is to introduce carbon-containing materials into iron oxide, such as porous hard carbon, carbon nanotubes, and graphene. Carbon materials not only improve the conductivity of the material but also buffer the volume expansion of Fe2O3 during charge and discharge. Research on using natural biomass materials and biomass waste to prepare carbon materials for lithium-ion battery anodes is extensive, and researchers have been striving to find inexpensive biomass raw materials as hard carbon sources and suitable pyrolysis processes to improve cycle performance. How to combine biomass-derived carbon materials with nano-Fe2O3 to obtain high-performance and low-cost nano-Fe2O3@carbon composite materials as anode materials for lithium-ion batteries is a significant problem. Bamboo resources are abundant, and bamboo grows rapidly, reaching maturity in a short time. Therefore, this patent uses bamboo leaves as a carbon source to prepare carbon materials, and then prepares nano-Fe2O3 / bamboo leaf carbon anode materials through a hydrothermal combined with a solvothermal method. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing Fe2O3 / bamboo leaf carbon lithium-ion battery anode materials. This invention uses bamboo leaves as the carbon source, preparing bamboo leaf carbon through calcination and hydrofluoric acid treatment, then preparing nano-Fe2O3 via a hydrothermal method, and finally combining the bamboo leaf carbon and nano-Fe2O3 via a solvothermal method to obtain the Fe2O3 / bamboo leaf carbon composite material. This composite material effectively solves problems such as easy pulverization, large charge-discharge volume changes, and poor cycle performance in conventional material preparation processes.

[0005] This invention provides a method for preparing Fe2O3 / bamboo leaf carbon composite lithium-ion battery anode material, comprising the following steps:

[0006] (1) Wash the bamboo leaves and dry them;

[0007] (2) Place the bamboo leaves in an inert atmosphere heating furnace for heat treatment;

[0008] (3) The bamboo leaf carbon obtained after heat treatment is ball-milled to obtain bamboo leaf carbon powder;

[0009] (4) The above bamboo leaf carbon powder was treated with hydrofluoric acid solution to remove silicon.

[0010] (5) The intermediate was prepared by hydrothermal method using Fe(NO3)3·9H2O, NH4F and urea as raw materials;

[0011] (6) The above intermediate was calcined in air to obtain nano Fe2O3;

[0012] (7) Using a mixture of anhydrous ethanol and N,N-dimethylformamide (DMF) as a solvent, bamboo leaf carbon and nano Fe2O3 were combined by a solvothermal method to obtain Fe2O3 / bamboo leaf carbon composite material.

[0013] As an optimization, the heat treatment temperature in step (2) is 800-1200℃ and the heat treatment time is 1-5 hours;

[0014] As an optimization, the ball milling time in step (3) is 10-50 hours;

[0015] As an optimization, the mass percentage concentration of the hydrofluoric acid solution in step (4) is 3-10%;

[0016] As an optimization, the hydrothermal reaction temperature in step (5) is 120-150℃, the heat preservation time is 2-10 hours, and then it is naturally cooled;

[0017] As an optimization, the calcination temperature in step (6) is 400-1000℃ and the calcination time is 2-8 hours;

[0018] As an optimization, in step (7), Fe2O3 and bamboo leaf carbon are poured into a beaker containing DMF and anhydrous ethanol, and magnetically stirred for 30-100 min. The well-mixed sample is then poured into a hydrothermal reactor and kept at 120-200℃ in a forced-air drying oven for 15-30 h. After the reaction is completed, the reactor is cooled to room temperature, and the reaction solution is filtered and washed to obtain the Fe2O3 / bamboo leaf carbon composite material, which is then dried in an oven at 60℃.

[0019] The present invention has the following beneficial effects:

[0020] 1. In view of the problem that the lithium storage capacity of graphite, the negative electrode material currently used in the field of lithium-ion batteries, is low, this invention has produced a Fe2O3 / bamboo leaf carbon composite negative electrode material with higher lithium storage capacity. This novel electrode material has high practical value.

[0021] 2. To address the issues of poor conductivity and volume expansion of Fe2O3 as a negative electrode material for lithium-ion batteries, this invention employs a solvothermal method to composite bamboo leaf carbon with Fe2O3, effectively improving the conductivity and volume effect of the electrode material.

[0022] 3. Addressing the issues of insufficient raw material sources and high costs associated with existing biomass carbon anode materials, this invention uses bamboo leaves as a carbon source to prepare biochar. Bamboo is widely cultivated in my country and its production is rapid, making this raw material abundant and inexpensive. Furthermore, the preparation method is simple, efficient, and rapid, facilitating widespread application. Attached Figure Description

[0023] Figure 1 XRD pattern of Fe2O3 (50%) / bamboo leaf carbon composite material;

[0024] Figure 2 Raman spectrum of Fe2O3 (50%) / bamboo leaf carbon composite material;

[0025] Figure 3 SEM image of Fe2O3 (50%) / bamboo leaf carbon composite material;

[0026] Figure 4 SEM image of Fe2O3 (60%) / bamboo leaf carbon composite material;

[0027] Figure 5 SEM image of Fe2O3 (70%) / bamboo leaf carbon composite material;

[0028] Figure 6 SEM image of Fe2O3 (30%) / bamboo leaf carbon composite material; Detailed Implementation

[0029] The present invention will now be described in more detail by way of examples, but the following embodiments are merely illustrative and the scope of protection of the present invention is not limited to these embodiments.

[0030] The technical solution of the present invention will be further described below with reference to specific embodiments:

[0031] Example 1

[0032] Step 1: Clean the collected bamboo leaves with tap water until the water is clear, then ultrasonically clean them several times with deionized water and anhydrous ethanol, and then put the cleaned bamboo leaves into a constant temperature drying oven at 80℃ for 24 hours.

[0033] Step 2: Place the dried sample into a tube furnace and heat it at 800°C for 2 hours under a nitrogen atmosphere;

[0034] Step 3: The calcined sample is ball-milled to obtain bamboo leaf charcoal powder;

[0035] Step 4: Then soak the powder in a 5% HF solution for 2 hours, and finally rinse it with deionized water and anhydrous ethanol and dry it to obtain bamboo leaf charcoal powder.

[0036] Step 5: Add 1g Fe(NO3)3·9H2O, 0.4g Urea, and 0.197g NH4F to a beaker containing 46mL of deionized water and stir until homogeneous. Then, place the homogeneous solution into a hydrothermal reactor and maintain the temperature at 140℃ for 12 hours. After the reactor cools down, remove it. Filter, wash, and dry the removed sample to obtain the intermediate.

[0037] Step 6: Transfer to a tube furnace and hold at 500°C for 3 hours in air atmosphere to obtain Fe2O3;

[0038] Step 7: Mix 15 mL of anhydrous ethanol and 15 mL of N,N-dimethylformamide (DMF) thoroughly and pour into a beaker. Then, add Fe2O3 and bamboo leaf charcoal to the beaker containing DMF and anhydrous ethanol at a Fe2O3 content of 50% (mass percentage). Stir on a magnetic stirrer for 30 min, then sonicate for 30 min. Finally, pour the thoroughly mixed sample into a hydrothermal reactor and keep it at 160℃ in a forced-air drying oven for 24 h. After the reactor cools, filter the sample and then place it in a forced-air drying oven at 60℃ for 6 h to remove the solvent, obtaining a dark red product, i.e., the Fe2O3 / bamboo leaf charcoal composite material. This method is based on Example 1, changing the ratio of Fe2O3 to bamboo leaf charcoal to 50% of the total weight of Fe2O3, while keeping other aspects unchanged, and can also obtain the Fe2O3 / bamboo leaf charcoal composite material.

[0039] Figure 1X-ray diffraction (XRD) patterns of a Fe2O3 / bamboo leaf carbon composite material containing 50% Fe2O3 are presented. The patterns clearly show a series of diffraction peaks at 2θ angles of 24.1°, 33.2°, 35.7°, 40.9°, 49.5°, 54.1°, 57.6°, 62.4°, 64.1°, and 72°. These peaks precisely match the (012), (104), (110), (113), (024), (116), (122), (214), (300), and (1,0,10) crystal planes (JCPS No. 89-0596) in the hexagonal close-packed structure of α-Fe2O3, i.e., ferric oxide. The sharpness of the diffraction peaks in the XRD pattern indicates that the Fe2O3 component in the composite material has extremely high crystallinity, meaning that the Fe2O3 crystal structure in the composite material is complete.

[0040] Figure 2 The image shows the Raman spectrum of the Fe2O3 / bamboo leaf carbon composite material. Two characteristic peaks of the carbon material are clearly visible in the image, with the peak at 1341 cm⁻¹ being the most prominent. -1 The peak at 1584 cm⁻¹ represents the D peak of carbon materials, indicating the degree of defects and disorder in the material. -1 The G peak represents the lattice vibrations and degree of order in carbon materials, while the ID / IG ratio is used to characterize the degree of graphitization in carbon materials. Figure 2 It can be seen that bamboo leaf carbon was successfully introduced into Fe2O3, and the ID / IG value of bamboo leaf carbon is 1.045, indicating that bamboo leaf carbon has a high degree of graphitization and a certain degree of defect, which also indicates that the Fe2O3 / bamboo leaf carbon material has good electrical conductivity. Furthermore, at 214 cm⁻¹... -1 275cm -1 384cm -1 586cm -1 There are four small peaks, one of which is at 214 cm. -1 275cm -1 A corresponding to α-Fe2O3 1g Modal, 384cm -1 and 586cm -1 E corresponding to α-Fe2O3 g The modalities are consistent with the Raman spectral peaks of α-Fe₂O₃ reported in the literature. Therefore, the results of XRD and Raman spectroscopy demonstrate that the Fe₂O₃ / bamboo leaf carbon composite material synthesized in this chapter possesses excellent crystallinity and electrical conductivity.

[0041] Figure 3The image shows a SEM image of a Fe2O3 / bamboo leaf carbon composite with a 50% Fe2O3 content. The image reveals that almost no tetragonal Fe2O3 is present, indicating reduced Fe2O3 aggregation. The synergistic effect between the two components suppresses the volume expansion of Fe2O3 and improves conductivity. The Fe2O3 and bamboo leaf carbon are uniformly bonded. The uneven surface of the bamboo leaf carbon increases its specific surface area, facilitating Fe2O3 anchoring and resulting in a tighter bond. This enhances the overall conductivity of the composite material with Li. + The active site of the reaction.

[0042] Example 2

[0043] Step 1: Clean the collected bamboo leaves with tap water until the water is clear, then ultrasonically clean them several times with deionized water and anhydrous ethanol, and then put the cleaned bamboo leaves into a constant temperature drying oven at 80℃ for 24 hours.

[0044] Step 2: Place the dried sample into a tube furnace and heat it at 800°C for 2 hours under a nitrogen atmosphere;

[0045] Step 3: The calcined sample is ball-milled to obtain bamboo leaf charcoal powder;

[0046] Step 4: Then soak the powder in a 5% HF solution for 2 hours, and finally rinse it with deionized water and anhydrous ethanol and dry it to obtain bamboo leaf charcoal powder.

[0047] Step 5: Add 1g Fe(NO3)3·9H2O, 0.4g Urea, and 0.197g NH4F to a beaker containing 46mL of deionized water and stir until homogeneous. Then, place the homogeneous solution into a hydrothermal reactor and maintain the temperature at 140℃ for 12 hours. After the reactor cools down, remove it. Filter, wash, and dry the removed sample to obtain the intermediate.

[0048] Step 6: Transfer to a tube furnace and hold at 500°C for 3 hours in air atmosphere to obtain Fe2O3;

[0049] Step 7: Mix 15 mL of anhydrous ethanol and 15 mL of N,N-dimethylformamide (DMF) thoroughly and pour into a beaker. Then, add Fe2O3 and bamboo leaf charcoal to the beaker containing DMF and anhydrous ethanol at a Fe2O3 content of 60% (mass percentage). Stir on a magnetic stirrer for 30 min, then sonicate for 30 min. Finally, pour the thoroughly mixed sample into a hydrothermal reactor and keep it at 160℃ in a forced-air drying oven for 24 h. After the reactor cools, filter the sample and then keep it at 60℃ in a forced-air drying oven for 6 h to remove the solvent, obtaining a dark red product, i.e., the Fe2O3 / bamboo leaf charcoal composite material. This method is based on Example 1, changing the ratio of Fe2O3 to bamboo leaf charcoal to 60% of the total weight of Fe2O3, while keeping other aspects unchanged, and can also obtain the Fe2O3 / bamboo leaf charcoal composite material.

[0050] Figure 4 The image shows a SEM image of a Fe2O3 / bamboo leaf carbon composite with a 60% Fe2O3 content. The image reveals that the bamboo leaf carbon particles are stacked together, reducing the adhesion between the nanorod-shaped Fe2O3 particles. However, a small number of tetragonal Fe2O3 crystals are observed. Since Fe2O3 particles are uniform in size when prepared individually, the tetragonal crystals appearing during composite formation may be due to the re-crystallization of Fe2O3 during solvothermal self-assembly. The reduced adhesion between the nanorod-shaped Fe2O3 particles leads to a tighter bond between Fe2O3 and bamboo leaf carbon. The synergistic effect of bamboo leaf carbon and Fe2O3 effectively mitigates the volume expansion of Fe2O3 and increases the conductivity of the composite material.

[0051] Example 3

[0052] Step 1: Clean the collected bamboo leaves with tap water until the water is clear, then ultrasonically clean them several times with deionized water and anhydrous ethanol, and then put the cleaned bamboo leaves into a constant temperature drying oven at 80℃ for 24 hours.

[0053] Step 2: Place the dried sample into a tube furnace and heat it at 800°C for 2 hours under a nitrogen atmosphere;

[0054] Step 3: The calcined sample is ball-milled to obtain bamboo leaf charcoal powder;

[0055] Step 4: Then soak the powder in a 5% HF solution for 2 hours, and finally rinse it with deionized water and anhydrous ethanol and dry it to obtain bamboo leaf charcoal powder.

[0056] Step 5: Add 1g Fe(NO3)3·9H2O, 0.4g Urea, and 0.197g NH4F to a beaker containing 46mL of deionized water and stir until homogeneous. Then, place the homogeneous solution into a hydrothermal reactor and maintain the temperature at 140℃ for 12 hours. After the reactor cools down, remove it. Filter, wash, and dry the removed sample to obtain the intermediate.

[0057] Step 6: Transfer to a tube furnace and hold at 500°C for 3 hours in air atmosphere to obtain Fe2O3;

[0058] Step 7: Mix 15 mL of anhydrous ethanol and 15 mL of N,N-dimethylformamide (DMF) thoroughly and pour into a beaker. Then, add Fe2O3 and bamboo leaf charcoal to the beaker containing DMF and anhydrous ethanol at a Fe2O3 content of 70% (mass percentage). Stir on a magnetic stirrer for 30 min, then sonicate for 30 min. Finally, pour the thoroughly mixed sample into a hydrothermal reactor and keep it at 160℃ in a forced-air drying oven for 24 h. After the reactor cools, filter the sample and then place it in a forced-air drying oven at 60℃ for 6 h to remove the solvent, obtaining a dark red product, i.e., the Fe2O3 / bamboo leaf charcoal composite material. This method is based on Example 1, changing the ratio of Fe2O3 to bamboo leaf charcoal to 70% of the total weight of Fe2O3, while keeping other aspects unchanged, and can also obtain the Fe2O3 / bamboo leaf charcoal composite material.

[0059] Figure 5 The image shows a SEM image of Fe2O3 / bamboo leaf carbon with a Fe2O3 content of 70%. As can be seen from the image, in Fe2O3 / bamboo leaf carbon with a Fe2O3 content of 70%, fine nano Fe2O3 particles are linked together to form a Fe2O3 network. Then, the Fe2O3 network is combined with the bamboo leaf carbon. This may be due to the adhesion between Fe2O3 particles caused by the solvothermal reaction at 160℃.

[0060] Example 4

[0061] Step 1: Clean the collected bamboo leaves with tap water until the water is clear, then ultrasonically clean them several times with deionized water and anhydrous ethanol, and then put the cleaned bamboo leaves into a constant temperature drying oven at 80℃ for 24 hours.

[0062] Step 2: Place the dried sample into a tube furnace and heat it at 800°C for 2 hours under a nitrogen atmosphere;

[0063] Step 3: The calcined sample is ball-milled to obtain bamboo leaf charcoal powder;

[0064] Step 4: Then soak the powder in a 5% HF solution for 2 hours, and finally rinse it with deionized water and anhydrous ethanol and dry it to obtain bamboo leaf charcoal powder.

[0065] Step 5: Add 1g Fe(NO3)3·9H2O, 0.4g Urea, and 0.197g NH4F to a beaker containing 46mL of deionized water and stir until homogeneous. Then, place the homogeneous solution into a hydrothermal reactor and maintain the temperature at 140℃ for 12 hours. After the reactor cools down, remove it. Filter, wash, and dry the removed sample to obtain the intermediate.

[0066] Step 6: Transfer to a tube furnace and hold at 500°C for 3 hours in air atmosphere to obtain Fe2O3;

[0067] Step 7: Mix 15 mL of anhydrous ethanol and 15 mL of N,N-dimethylformamide (DMF) thoroughly and pour into a beaker. Then, add Fe2O3 and bamboo leaf charcoal to the beaker containing DMF and anhydrous ethanol at a Fe2O3 content of 30% (mass percentage). Stir on a magnetic stirrer for 30 min and then sonicate for 30 min. Finally, pour the thoroughly mixed sample into a hydrothermal reactor and keep it at 160℃ in a forced-air drying oven for 24 h. After the reactor cools, filter the sample and then keep it at 60℃ in a forced-air drying oven for 6 h to remove the solvent, obtaining a dark red product, namely the Fe2O3 / bamboo leaf charcoal composite material. This method is based on Example 1, changing the ratio of Fe2O3 to bamboo leaf charcoal to 30% of the total weight of Fe2O3, while keeping other aspects unchanged, and can also obtain the Fe2O3 / bamboo leaf charcoal composite material.

[0068] Figure 6 The image shows a SEM image of Fe2O3 / bamboo leaf carbon with a Fe2O3 content of 30%. It can be seen from the image that the amount of Fe2O3 is significantly reduced and there is agglomeration. This results in only a few Fe2O3 particles adhering to the surface of some bamboo leaf carbon. Since Fe2O3 is the main component that provides capacity, too low a Fe2O3 content will lead to a decrease in the overall capacity of the composite material. Therefore, controlling the ratio between Fe2O3 and bamboo leaf carbon is particularly important.

[0069] The Fe2O3 / bamboo leaf carbon composite anode materials prepared in the embodiments of the present invention were used to make half-cells for testing, and the specific data are shown in Table 1.

[0070] Fe2O3 / bamboo leaf carbon and conductive agent (acetylene black) were ground and mixed evenly in an agate mortar at a mass ratio of 70:15. Then, 15% by mass of binder (polyvinylidene fluoride, PVDF) and solvent (NMP) were added to form a uniform slurry. The slurry was then evenly coated onto the current collector and immediately placed in a 60°C forced-air drying oven for drying. After the solvent evaporated, the electrode was obtained and stored in a glove box for later use.

[0071] The battery assembly was conducted in a nitrogen-filled glove box. The electrolyte was a 1M LiPF6 EC / DEC (volume ratio 1:1) solution, and a lithium metal sheet was used as the counter electrode. Electrochemical performance tests were performed on a battery tester. The charge / discharge voltage range was 0.01 to 3V, and the charge / discharge current density was 200 mA / g. The following experimental data were obtained.

[0072] Table 1:

[0073]

Claims

1. A method for preparing a Fe2O3 / bamboo leaf carbon composite lithium-ion battery anode material, characterized in that, Includes the following steps: (1) Wash the bamboo leaves and dry them; (2) Calcine the above bamboo leaves in an inert atmosphere in an atmosphere heating furnace at 800-1200℃ for 1-5 hours; (3) The calcined sample was ball-milled for 24-72 hours to obtain bamboo leaf char powder; (4) Then the powder is soaked in 3-10% HF solution for 1-10 hours to corrode the silicon element in the bamboo leaf carbon. Finally, it is rinsed with deionized water and anhydrous ethanol and then dried to obtain bamboo leaf carbon. (5) Dissolve Fe(NO3)3·9H2O, NH4F and urea in deionized water in a certain proportion and transfer them to the lining of a high-pressure reactor. Heat the reactor to 120-150℃ and keep it at that temperature for 2-10 hours. Then cool it naturally to obtain the intermediate. (6) The above intermediate was calcined in a muffle furnace at 400-1000℃ for 2-8h to obtain Fe2O3, with air as the calcination atmosphere; (7) Mix anhydrous ethanol and N,N-dimethylformamide (DMF) evenly and pour into a beaker. Then pour Fe2O3 and bamboo leaf charcoal into the beaker containing DMF and anhydrous ethanol and stir on a magnetic stirrer for 30-100 min. Pour the evenly mixed sample into a hydrothermal reactor and keep it in a forced-air drying oven at 120-200℃ for 15-30 h. (8) After the reaction vessel is cooled, the sample is filtered and then placed in a drying oven at 50-80℃ for 5-10 hours to remove the solvent, resulting in a dark red product, namely Fe2O3 / bamboo leaf carbon composite material.

2. The preparation method of the Fe2O3 / bamboo leaf carbon composite lithium-ion battery anode material according to claim 1, characterized in that, In step (2), the calcination atmosphere is an inert atmosphere such as nitrogen or argon, the calcination temperature is 800-1200℃, and the calcination time is 1-5h.

3. The preparation method of the Fe2O3 / bamboo leaf carbon composite lithium-ion battery anode material according to claim 1, characterized in that, The corrosive solution used in step (4) is a 3-10% HF solution, and the treatment time is 1-10 hours.

4. The preparation method of the Fe2O3 / bamboo leaf carbon composite lithium-ion battery anode material according to claim 1, characterized in that, The raw materials used in step (5) are Fe(NO3)3·9H2O, NH4F, and urea. An intermediate is prepared by hydrothermal reaction at a temperature of 120-150℃ and a holding time of 2-10 hours.

5. The preparation method of the Fe2O3 / bamboo leaf carbon composite lithium-ion battery anode material according to claim 1, characterized in that, The calcination temperature in step (6) is 400-1000℃, the calcination time is 2-8 hours, and the calcination atmosphere is air.

6. The preparation method of the Fe2O3 / bamboo leaf carbon composite lithium-ion battery anode material according to claim 1, characterized in that, The solvent used in step (7) is a mixture of anhydrous ethanol and N,N-dimethylformamide (DMF), the treatment temperature is 120-200℃, and the holding time is 15-30 hours.

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