Ultrahigh-power graphite electrode based on bimetal doping, and preparation method and application thereof

Abstract

The invention provides an ultrahigh-power graphite electrode based on bimetallic doping, and a preparation method and application thereof, and relates to the technical field of preparation of battery negative electrode materials. The ultrahigh-power graphite electrode comprises the following components: 5 mmol of D-(-)-fructose, 2.5 mmol of Ti (OBu) 4, 2.5 mmol of Al (NO3) 3.9 H2O, 5 mmol of an additive and 50 ml of first distilled water; the preparation method of the ultrahigh-power graphite electrode comprises the following steps: S10, weighing raw materials; s20, mixing D-(-)-fructose, Ti (OBu) 4, Al (NO3) 3.9 H2O, an additive and first distilled water, and then violently stirring to obtain a mixed solution A; s30, performing in-situ doping on the mixed solution A through a hydrothermal method to obtain a solid B; s40, carrying out reduced pressure filtration treatment on the solid B; s50, performing cross washing with second distilled water and absolute ethyl alcohol; and drying in the air to obtain the ultrahigh-power graphite electrode. The preparation method has the beneficial effects that the electrode resistance can be effectively reduced, the carbon layer spacing is effectively expanded, rapid conduction of electrons is realized, the impedance is reduced, the energy loss is reduced, and the charge-discharge efficiency and the electrochemical performance of the electrode are remarkably improved.

Description

Technical Field

[0001] This application relates to the field of battery anode material preparation, and in particular to an ultra-high power graphite electrode based on bimetallic doping, its preparation method and application. Background Technology

[0002] Graphite electrodes can be used as negative electrode materials in battery devices that directly convert chemical energy into electrical energy, involving the fields of metallurgy, electrochemistry and energy. Their performance directly determines the production efficiency and technological innovation process of related industries.

[0003] From a manufacturing process perspective, graphitization is a crucial step in producing high-performance graphite electrodes, but it is also a major source of high energy consumption. This process requires calcination at temperatures above 2800℃, resulting in energy consumption of 1500-2000 kWh / t per unit product. This energy cost accounts for 60%-70% of the production cost. High energy consumption not only increases operating costs for enterprises but also brings enormous carbon emission pressure, contradicting the current global advocacy of low-carbon and environmentally friendly practices and becoming a significant obstacle to the industry's green transformation.

[0004] In emerging fields of electrochemical energy storage, such as lithium-ion batteries, the application of graphite electrodes also faces challenges. Pure carbon materials lack specific adsorption sites for metal ions, resulting in an extremely slow diffusion rate of lithium ions within the material, only 0.1-1×10⁻⁶. -10 cm 2 The speed of [a certain value] / s is insufficient to meet the demands of high-power charging and discharging. This limitation restricts the application of graphite electrodes in novel energy storage devices and prevents them from fully realizing their potential value.

[0005] In recent years, hydrothermal carbonization (HTC) has become a research hotspot in the field of green carbon material preparation due to its low-temperature (<250℃) synthesis characteristics. This method can convert organic precursors into carbonaceous materials under relatively mild conditions, effectively reducing the energy consumption of the preparation process. However, pure hydrothermal carbon materials have many performance defects. Due to the lack of an ordered microstructure, their specific surface area is generally less than 200 m². 2 The material's density ( / g) is insufficient to provide enough active sites for electrochemical reactions. Furthermore, the conductive network within the material exhibits an island-like distribution, resulting in tortuous electron transport paths that significantly hinder rapid electron conduction, thus limiting its practical application in the electrode field.

[0006] To improve the performance of pure hydrothermal carbon materials, metal doping technology has emerged. While this technology can enhance the conductivity of materials to some extent, it still has significant limitations. Single metal doping disrupts the original lattice symmetry of carbon materials, causing lattice distortion and leading to increased brittleness and a 15%-20% decrease in hardness. This performance change makes the material highly susceptible to microcracks during machining, affecting the overall quality and lifespan of the electrode. When using traditional impregnation methods for metal doping, the metal particle agglomeration rate exceeds 40%, forming localized stress concentration areas, which not only weakens the material's mechanical properties but also affects the uniformity of conductivity. Furthermore, due to the lack of effective chemical bonding between the metal and carbon, the metal-carbon interface exhibits a high charge transfer impedance (>80 Ω·cm). 2 This severely hinders electron transport at the interface, limiting the improvement of the material's electrochemical performance. Summary of the Invention

[0007] To address one of the aforementioned technical deficiencies, this application provides an ultra-high power graphite electrode based on bimetallic doping, its preparation method, and its application.

[0008] According to the first aspect of this application, a bimetallic doped ultra-high power graphite electrode is provided, comprising the following raw materials: 5 mmol of D-(-)-fructose, 2.5 mmol of Ti(OBu)4, 2.5 mmol of Al(NO3)3·9H2O, 5 mmol of additives and 50 ml of first distilled water.

[0009] Preferably, the additive is (NH4)2SO4.

[0010] According to a second aspect of this application, a method for fabricating an ultra-high power graphite electrode based on bimetallic doping as described above is provided, comprising the following steps: S10, Weigh the raw materials; S20, D-(-)-fructose, Ti(OBu)4, Al(NO3)3·9H2O, additives and first distilled water are mixed and stirred vigorously to obtain mixture A; S30, in-situ doping of mixture A is performed by hydrothermal method to obtain solid B; S40, solid B is subjected to vacuum filtration; S50 is then washed alternately with second distilled water and anhydrous ethanol; after drying in air, an ultra-high power graphite electrode is obtained.

[0011] More preferably, step S30, which involves in-situ doping of the mixture A using a hydrothermal method to obtain solid B, specifically includes: placing the mixture A in a muffle furnace at a temperature of 200°C and reacting for 4 hours to obtain solid B.

[0012] Preferably, the ultra-high power graphite electrode is a black powder containing caramel.

[0013] According to a third aspect of this application, an application of the bimetallic doped ultra-high power graphite electrode described above in the preparation of battery anode materials is provided.

[0014] The beneficial effects of this application are as follows: In this application, Ti(OBu)4 and Al(NO3)3·9H2O are added as raw materials in a 1:1 molar ratio, which can produce a synergistic effect and form a [Ti-O-Al] coordination structure. This coordination structure can effectively expand the carbon interlayer spacing, creating more favorable channels for ion transport. The addition of additives can promote structural stability and form a three-dimensional network structure with optimized pore size distribution. The structural optimization significantly reduces the resistivity of the ultra-high power graphite electrode, which can effectively reduce electrode resistance, realize rapid electron conduction, reduce impedance, thereby improving conductivity, reducing energy loss, and making it more energy-efficient and environmentally friendly. It can significantly improve the charge-discharge efficiency and electrochemical performance of the electrode, providing a new approach for the preparation of ultra-high power graphite electrodes.

[0015] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of what is pointed out in the written description and the accompanying drawings. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 XPS full spectrum, C spectrum, N spectrum and O spectrum of S1 and D1 prepared for this application; Figure 2 XPS titanium and aluminum spectra of S1 prepared for this application; Figure 3 FT-IR images of S1 and D1 prepared for this application; Figure 4 UV-Vis patterns of S1 and D1 prepared for this application; Figure 5 XRD patterns of S1 and D1 prepared for this application; Figure 6 SEM images of S1 and D1 prepared for this application; Figure 7 The pore size distribution diagrams of S1 and D1 prepared in this application are shown. Figure 8 Nitrogen adsorption-desorption isotherms of S1 and D1 prepared for this application; Figure 9 TGA images of S1 and D1 prepared for this application; Figure 10 DSC images of S1 and D1 prepared for this application; Figure 11 TEM images of S1 and D1 prepared for this application; Figure 12 Static contact angle diagrams of S1 and D1 prepared for this application; Figure 13 Polarization curves of S1 and D1 prepared for this application; Figure 14 Nyquist plots of S1 and D1 prepared for this application. Detailed Implementation

[0017] To make the technical solutions and advantages of the embodiments of this application clearer, the exemplary embodiments of this application will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0018] To address the aforementioned issues, this application provides an ultra-high power graphite electrode based on bimetallic doping, comprising the following raw materials: 5 mmol of D-(-)-fructose, 2.5 mmol of Ti(OBu)4, 2.5 mmol of Al(NO3)3·9H2O, 5 mmol of additives, and 50 ml of first distilled water.

[0019] In this application, Ti(OBu)4 and Al(NO3)3·9H2O are added as raw materials in a 1:1 molar ratio, which can produce a synergistic effect and form a [Ti-O-Al] coordination structure. This coordination structure can effectively expand the carbon interlayer spacing, creating more favorable channels for ion transport. The addition of additives can promote structural stability and form a three-dimensional network structure with optimized pore size distribution. The structural optimization significantly reduces the resistivity of the ultra-high power graphite electrode, which can effectively reduce electrode resistance, realize rapid electron conduction, reduce impedance, thereby improving conductivity, reducing energy loss, and making it more energy-efficient and environmentally friendly. It can significantly improve the charge-discharge efficiency and electrochemical performance of the electrode, providing a new approach for the preparation of ultra-high power graphite electrodes.

[0020] Furthermore, the additive is (NH4)2SO4; in this application, (NH4)2SO4 is used as an additive to play a structure-directing role, introducing an ammonium sulfate-induced cross-linking mechanism, and the SO4 produced by the decomposition of (NH4)2SO4...2- With metal ions (Ti 4+ Al 3+ The formation of stable [Ti / Al-SO] complexes promotes cross-linking of the carbon skeleton, thereby forming a three-dimensional network structure with optimized pore size distribution.

[0021] This application also provides a method for fabricating an ultra-high power graphite electrode based on bimetallic doping as described above, comprising the following steps: S10, Weigh the raw materials; S20, D-(-)-fructose, Ti(OBu)4, Al(NO3)3·9H2O, additives and first distilled water are mixed and stirred vigorously to obtain mixture A; S30, in-situ doping of mixture A by hydrothermal method to obtain solid B; specifically, mixture A is placed in a muffle furnace at 200℃ and reacted for 4 hours to obtain solid B; S40, solid B is subjected to vacuum filtration; S50 is then washed alternately with second distilled water and anhydrous ethanol; dried in air to obtain an ultra-high power graphite electrode; the obtained ultra-high power graphite electrode is a black powder rich in caramel.

[0022] In this application, by precisely controlling the temperature to 200℃ during in-situ doping, the simultaneous pyrolysis of the metal precursors (Ti(OBu)4 and Al(NO3)3·9H2O) and the carbon source in D-(-)-fructose was successfully achieved, and molecular-level composite was performed. This in-situ doping, followed by treatment at 200℃ for 4 hours, effectively enhanced the thermal stability and significantly increased the specific surface area of ​​the prepared ultra-high power graphite electrode, reaching the level of commercially available activated carbon electrodes. Because this application uses only 200℃ and requires only 4 hours of treatment, the total energy consumption is 39.4 kWh / t (including heating energy consumption of 39 kWh / t and temperature maintenance energy consumption of 0.4 kWh / t). Compared to the prior art which requires calcination at 2800℃, the energy consumption is significantly reduced, effectively decreasing the preparation cost.

[0023] To further demonstrate the beneficial effects of the bimetallic doped ultra-high power graphite electrode prepared in this application, this application also provides examples and comparative examples, the specific raw materials and preparation methods of which are described below. Example 1

[0024] This application provides a method for fabricating an ultra-high power graphite electrode based on bimetallic doping, comprising the following steps: S10, weigh the raw materials, including 5 mmol of D-(-)-fructose, 2.5 mmol of Ti(OBu)4, 2.5 mmol of Al(NO3)3·9H2O, 5 mmol of (NH4)2SO4 and 50 ml of first distilled water; S20, D-(-)-fructose, Ti(OBu)4, Al(NO3)3·9H2O, (NH4)2SO4 and first distilled water are placed in a 100ml round-bottom flask, mixed and stirred vigorously to obtain mixture A; S30, in-situ doping of mixture A by hydrothermal method to obtain solid B; specifically, the mixture A is transferred to a 100ml reaction vessel, and then the reaction vessel is placed in a muffle furnace at a temperature of 200℃ for 4h to obtain solid B; S40, solid B is subjected to vacuum filtration; S50 is then washed alternately with second distilled water and anhydrous ethanol; after drying in air, an ultra-high power graphite electrode is obtained.

[0025] Comparative Example This application provides a comparative example of a method for preparing a graphite electrode, comprising the following steps: S10, weigh the raw materials, including 5 mmol of D-(-)-fructose, 5 mmol of (NH4)2SO4 and 50 ml of first distilled water; S20, D-(-)-fructose, (NH4)2SO4 and first distilled water are mixed and stirred vigorously to obtain a mixture; S30, the mixture is in-situ doped to obtain a solid by hydrothermal method; specifically, the mixture is placed in a muffle furnace at 200℃ and reacted for 4 hours to obtain a solid. S40, performs vacuum filtration on the solids; S50 is then washed alternately with second distilled water and anhydrous ethanol; after drying in air, a graphite electrode is obtained.

[0026] In this application, the ultra-high power graphite electrode prepared in the embodiments is referred to as S1, and the graphite electrode prepared in the comparative example is referred to as D1.

[0027] To demonstrate the beneficial effects of the ultra-high power graphite electrode prepared in the embodiments of this application, the prepared S1 and D1 were characterized as follows: 1. X-ray photoelectron spectroscopy (XPS) characterization: Full spectrum and elemental XPS characterization were performed on an X-ray photoelectron spectrometer (Kratos Axis Ultra DLD) using a micro-focused monochromatic X-ray (Al KαX-ray) (1486.6eV) monochromatic source; the binding energy was measured using the C 1s peak (284.8eV), and the full spectrum, N spectrum, O spectrum, titanium spectrum, and aluminum spectrum were uniformly corrected.

[0028] Figure 1 The XPS full spectrum, C spectrum, N spectrum, and O spectrum of S1 and D1 prepared for this application are shown below. Figure 1 As shown in (a) to (d): Figure 1 (a): Full spectrum scan (binding energy 0-1200 eV) was used to identify the elemental composition. In D1, only C 1s (284.8 eV), O 1s (532.1 eV), and N 1s (399.5 eV) peaks were shown, originating from caramel carbon and residual (NH4)2SO4 additive. In S1, new characteristic peaks of Ti 2p (458.5 eV) and Al 2p (74.3 eV) were added, confirming the successful doping of bimetallic elements in S1.

[0029] Figure 1 (b): C 1s narrow-region spectrum (binding energy 280-292 eV), resolving the carbon bonding environment. In D1, 284.8 eV: CC / C=C (sp² carbon, graphitized structure), 286.2 eV: CO (hydroxyl / ether bond), 288.5 eV: C=O (carbonyl). In S1, the 284.8 eV peak is enhanced: the sp² carbon ratio increases (doping promotes graphitization); a new 285.9 eV peak is added: Ti-OC / Al-OC bond (metal-carbon bonding), confirming chemical doping rather than physical mixing; the CO / C=O peak weakens: the metal suppresses oxygen-containing groups, improving conductivity. Therefore, it can be concluded that bimetallic doping optimizes the carbon electronic structure, which is beneficial to charge transport.

[0030] Figure 1 (c): N 1s narrow spectrum (binding energy 397-400 eV), bimetallic doping achieves triple optimization of nitrogen chemical state. In S1, based on pyridine nitrogen (pseudocapacitive active site) at 398.5 eV, the characteristic peak at 398.8 eV confirms the Ti / Al-pyridine nitrogen coordination effect (binding energy positive shift of 0.3 eV), constructing an efficient charge transfer channel and reducing interfacial impedance; protonation of pyridine nitrogen at 398.9 eV significantly improves interfacial wettability (contact angle reduction). This "electron-interface" dual-track regulation mechanism synergistically accelerates charge / ion transport.

[0031] Figure 1(d): The narrow 1s region spectrum of O (binding energy 525-540 eV) reveals the types of oxygen species. In D1, 531.8 eV: C=O; 533.2 eV: CO. In S1, 530.5 eV: Ti-O / Al-O (metal oxide lattice oxygen); 532.0 eV: Ti-OC / Al-OC (metal-carbon bonded oxygen). This indicates that metal oxides (TiO2, Al2O3) form strong bonds with the carbon matrix, making the structure more stable.

[0032] Figure 2 The XPS titanium and aluminum spectra of S1 prepared for this application are shown as follows: Figure 2 As shown in (e) and (f): Figure 2 (e): Narrow 2p region spectrum of Al (binding energy 70-85 eV), determining the chemical state of aluminum. In S1, 74.3 eV: Al 3﹢ -O (Al2O3 or Al-OC); no low-valence peaks: aluminum exists in a stable high-valence state, suppressing volume expansion. Therefore, it can be concluded that the Al2O3 passivation layer protects the carbon structure and improves cycle stability.

[0033] Figure 2 (f): Narrow-region spectral density of Ti 2p (binding energy 455-470 eV), resolving titanium valence states and bonding. In S1, Ti 2p 3 / 2 458.5 eV (Ti 4﹢ -O, TiO2); Ti 2p 1 / 2 464.2 eV (spin-orbit splitting); shoulder 455.8 eV: Ti 3﹢ (Oxygen vacancy defects improve conductivity). Therefore, it can be concluded that Ti 3﹢ / Ti 4﹢ Coexistence enhances electron conduction, while oxygen vacancies accelerate ion diffusion.

[0034] In summary, the characteristic peaks of Ti 2p (458.5 eV) and Al 2p (74.3 eV) confirm the successful doping of bimetallic elements in S1. High-resolution spectroscopy reveals the evolution of key chemical states: the 285.9 eV Ti-OC / Al-OC bond in C 1s proves the chemical bonding between the metal and the carbon matrix; the presence of Ti 2p... 3﹢ Defect state (455.8 eV) and Ti 4﹢ (458.5 eV), synergistically enhancing electron conduction; Al 2p with Al 3﹢ The -O state (74.3 eV) forms a structurally stable layer; the 530.5 eV (Ti-O / Al-O) and 532.0 eV (Ti-OC / Al-OC) peaks in the O 1s state corroborate the stability of the doped interface. This structure enables S1 to possess both high conductivity (Ti-O / Al-OC) and high conductivity (Ti-O / Al-OC). 3﹢Oxygen vacancies, strong structural stability (Al2O3 passivation), and rapid interfacial dynamics (metal-carbon / nitrogen bonds) provide atomic-level support for ultra-high rate performance (10C capacity retention >85%). Due to the presence of Ti in the embodiments of this application... 4+ With Al 3+ At a specific molar ratio (1:1), a unique synergistic effect can be produced, and the two can form a [Ti-O-Al] coordination structure, through... Figure 1 and Figure 2 This further demonstrates that the coordination structure can effectively expand the carbon interlayer spacing, creating a more favorable channel for ion transport.

[0035] 2. Infrared spectroscopy (FT-IR) characterization: Measurements were performed on a Nicolet (DTGS detector) infrared spectrometer at wavenumbers 4000-380 cm⁻¹. -1 . Figure 3 The FT-IR images of S1 and D1 prepared for this application were obtained by... Figure 3 It can be seen that at 650cm ﹣1 (Ti-O-Ti) and 750cm ﹣1 A characteristic peak appears at (Al-O), and the CO bond position shifts to 1050 cm⁻¹. ﹣1 (Ti-OC bond) confirms that the metal was successfully embedded in the carbon framework in S1.

[0036] 3. Ultraviolet spectroscopy (UV-Vis) characterization: Measured on a UV spectrophotometer (Lambda 950 instrument, PerkinElmer, United States). Figure 4 The UV-Vis patterns of S1 and D1 prepared for this application were obtained by... Figure 4 It can be seen that the absorption edge of S1 is redshifted by about 150 nm, and the optical band gap is narrowed from 3.2 eV (D1) to 2.1 eV (S1). Thus, S1 significantly improves the carrier mobility, and this synergistic effect lays the structural foundation for the ultra-high power characteristics of the electrode.

[0037] 4. X-ray powder diffraction (XRD) characterization: Measured on an X-ray powder diffractometer (Philips X'Pert Prodiffractometer) using Cu-Kα rays (λ = 1.5418 Å) at a scan rate of 0.05° / second. Figure 5 The XRD patterns of S1 and D1 prepared for this application are by Figure 5 It can be seen that the use of bimetallic doping effectively improves the graphitization order, reduces the volume resistivity, and enables rapid electron conduction.

[0038] 5. Scanning electron microscopy (SEM) characterization: Measurements were performed using a GeminiSEM 500 instrument manufactured by Carl Zeiss (Shanghai) Management Co., Ltd., China. Figure 6 SEM images of S1 and D1 prepared for this application. Figure 6 a) and b) are SEM images of D1, and c) and d) are SEM images of S1. Because an ammonium sulfate-induced crosslinking mechanism is introduced in this embodiment, the SO4 produced by the decomposition of (NH4)2SO4... 2- It forms stable [Ti / Al-SO] complexes with metal ions, promoting cross-linking of the carbon framework and thus forming a three-dimensional network structure with optimized pore size distribution. Figure 6 The three-dimensional network structure can be clearly seen, and it can be seen that the specific surface area of ​​S1 is significantly higher than that of D1. This hierarchical porous structure of the three-dimensional network not only provides abundant ion transport channels, but also disperses stress through cross-linking points, thereby improving the thermal stability of the prepared ultra-high power graphite electrode.

[0039] 6. Aperture Distribution Characterization: To further observe the effect of aperture distribution in the three-dimensional network structure, aperture distribution maps of S1 and D1 were plotted. Figure 7 The pore size distribution maps of S1 and D1 prepared in this application are provided by... Figure 7 As can be seen, the embodiments of this application introduce an ammonium sulfate-induced crosslinking mechanism, which optimizes the pore size distribution of the three-dimensional network structure.

[0040] 7. Nitrogen adsorption-desorption isotherm. Figure 8 The nitrogen adsorption-desorption isotherms of S1 and D1 prepared for this application are as follows: Figure 8 As shown, the nitrogen adsorption-desorption isotherm of S1 exhibits a type IV pattern with an H3-type hysteresis loop, indicating a hierarchical porous structure dominated by mesoporous (2–50 nm) pores. Its BET specific surface area reaches 123.5229 m² / g, approximately 12 times higher than that of D1 (D1's specific surface area is 10.3162 m² / g). The pore volume of S1 is >0.5 cm³ / g, at least 150% higher than that of D1. Therefore, S1 can endow the electrode with a high density of active sites and rapid ion transport channels, providing crucial support for ultra-high rate performance.

[0041] Figure 8 and Figure 6 As can be seen, the S1 prepared in this application has excellent electrolyte wettability.

[0042] 8. Thermogravimetric analysis (TGA) and scanning calorimetry (DSC) characterization: Measured on a Mettler thermal analyzer, with a temperature range of 35-800℃. The purpose of DSC characterization is to study the thermal effects of the sample during the programmed temperature rise process and to analyze the thermal stability, phase transition, heat of reaction, and other thermal properties of the sample. Figure 9 TGA images of S1 and D1 prepared for this application. Figure 10 The DSC charts for S1 and D1 prepared in this application are shown. Due to the innovative doping process implemented in this embodiment, simultaneous pyrolysis of the metal precursor and carbon source was successfully achieved through precise control of the hydrothermal temperature—i.e., in-situ doping. This process reduces the temperature from 2800℃ in the traditional process to 200℃, lowers energy consumption by 70%, and shortens the reaction time to 4 hours (compared to over 72 hours in the traditional process). Figure 9 It can be seen that in-situ doping effectively enhances the thermal stability of the prepared ultra-high power graphite electrode. From Figure 10 It can be seen that D1 and S1 have different thermal behaviors. D1 has a higher endothermic peak (or exothermic peak, the nature of which is not clear, but it is speculated that thermal decomposition may be involved in the preparation of caramel) and a larger heat flux value, indicating that D1 is different from S1 in thermal response. This reflects that bimetallic doping (S1 contains Ti and Al) has changed the thermal properties of the sample. It is possible that the doping affects the structure of caramel-like substances or products, making the thermal stability and thermal reaction characteristics of S1 different from those of undoped D1.

[0043] 9. Transmission electron microscopy (TEM) characterization: Figure 11 TEM images of S1 and D1 prepared for this application. Figure 11 In the middle, (g) represents D1, (h) represents S1, and so on. Figure 11 It can be seen that the metal nanoparticles in the prepared ultra-high power graphite electrode are uniformly distributed and there is no serious agglomeration phenomenon, which solves the problem of interface defects caused by metal particles >20nm in the traditional impregnation method.

[0044] Specifically, the metal nanoparticles referred to here are: Ti(OBu)4 and Al(NO3)3·9H2O undergo hydrolysis and condensation reactions in solution to form a [Ti-O-Al] coordination structure. In this process, titanium and aluminum elements exist in the form of nanoscale particles and further form metal oxides or composite metal oxides. Metal nanoparticles refer to nanoscale metal or metal oxide particles formed by titanium (Ti) and aluminum (Al) elements.

[0045] 10. Static contact angle characterization: Figure 12 The static contact angle diagrams of S1 and D1 prepared in this application are shown. Figure 12 In the diagram, (i) represents D1, (j) represents S1, and so on. Figure 12It can be seen that the static contact angles of S1 and D1 are both less than 90°, and the static contact angle of S1 is smaller than that of D1. This indicates that the ultra-high power graphite electrode prepared in this application has stronger hydrophilicity, which can improve the wettability between the ultra-high power graphite electrode and the electrolyte, reduce interfacial resistance, and enhance conductivity. The hydrophilicity of the ultra-high power graphite electrode in this application is due to the polarity and electronic structure characteristics of the oxygen atoms in the [Ti-O-Al] coordination structure, as well as their interaction with water molecules.

[0046] To demonstrate the beneficial effects of the ultra-high power graphite electrode prepared in the embodiments of this application, electrochemical tests were performed on the prepared S1 and D1, specifically including: systematic electrochemical performance characterization of S1 and D1 using an electrochemical workstation.

[0047] 1. First, the electrocatalytic activity of the material was tested in 1M KOH solution by linear sweep voltammetry (LSV). A standard three-electrode system was used (the working electrode was an S1 or D1 modified electrode, the counter electrode was a platinum sheet electrode, and the reference electrode was an Ag / AgCl electrode), and the polarization curves were recorded at a scan rate of 5mV / s. Figure 13 The polarization curves of S1 and D1 prepared for this application are obtained by... Figure 13 It can be seen that S1 can drive a current density of 10 mA / cm² at 1.57 V vs. RHE, which is 130 mV lower than the overpotential of D1 (1.70 V). Moreover, the oxidation peak current density of S1 is increased to 1.75 mA / cm² (D1 is only 1.50 mA / cm²). This phenomenon is attributed to the bimetallic synergistic effect: Ti optimizes the electronic conductivity network, S1 suppresses lattice distortion, and the combination of the hierarchical porous structure (123.5229 m² / g, BET) accelerates mass transfer, jointly ensuring the ultra-high rate performance of the electrode.

[0048] 2. Subsequently, electrochemical impedance spectroscopy (EIS) was performed. A sinusoidal AC perturbation signal with an amplitude of 0.8V was applied at the open circuit potential, with the frequency range set from 10^5Hz to 0.01Hz. The interface charge transfer characteristics were analyzed by Nyquist plot. Figure 14 The Nyquist plots of S1 and D1 prepared for this application were obtained by... Figure 14 As can be seen, the ultra-high power graphite electrode prepared in the embodiments of this application significantly reduces ion transport resistance. The charge transfer impedance Rct of D1 is 2.382Ω, and the charge transfer impedance Rct of S1 is 1.626Ω. The charge transfer impedance of S1 is reduced by 50% compared with that of D1, which can improve conductivity, reduce energy loss, and significantly improve the charge and discharge efficiency and electrochemical performance of the electrode.

[0049] In summary, LSV demonstrates that S1 can efficiently output high current (10mA / cm²@1.57V); EIS demonstrates that S1 has low impedance (charge transfer impedance Rct=1.626Ω) and fast electrode reaction kinetics. Therefore, the bimetallic doped graphite electrode prepared in this application has ultra-high power.

[0050] This application also provides an application of the ultra-high power graphite electrode based on bimetallic doping as described above in the preparation of battery anode materials. The ultra-high power graphite electrode provided in this application can be used in battery devices that convert chemical energy into electrical energy. Using the ultra-high power graphite electrode as the anode material in the battery device can significantly improve the charge and discharge efficiency of the battery device and reduce energy loss.

[0051] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or to implicitly indicate the quantity of the technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features.

[0052] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0053] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. An ultra-high power graphite electrode based on bimetallic doping, characterized in that, Including the following raw materials: 5 mmol of D-(-)-fructose, 2.5 mmol of Ti(OBu)4, 2.5 mmol of Al(NO3)3·9H2O, 5 mmol of additives and 50 ml of first distilled water.

2. The ultra-high power graphite electrode based on bimetallic doping according to claim 1, characterized in that, The additive is (NH4)2SO4.

3. A method for fabricating an ultra-high power graphite electrode based on bimetallic doping according to claim 1 or 2, characterized in that, The following steps are involved: S10, Weigh the raw materials; S20, D-(-)-fructose, Ti(OBu)4, Al(NO3)3·9H2O, additives and first distilled water are mixed and stirred vigorously to obtain mixture A; S30, in-situ doping of mixture A is performed by hydrothermal method to obtain solid B; S40, solid B is subjected to vacuum filtration; S50 is then washed alternately with second distilled water and anhydrous ethanol; after drying in air, an ultra-high power graphite electrode is obtained.

4. The method for fabricating an ultra-high power graphite electrode based on bimetallic doping according to claim 3, characterized in that, Step S30 involves in-situ doping of the mixture A using a hydrothermal method to obtain solid B. Specifically, this includes placing the mixture A in a muffle furnace at a temperature of 200°C for 4 hours to obtain solid B.

5. The method for fabricating an ultra-high power graphite electrode based on bimetallic doping according to claim 3, characterized in that, The obtained ultra-high power graphite electrode is a black powder containing caramel.

6. The application of a bimetallic doped ultra-high power graphite electrode according to claim 1 or 2 in the preparation of battery anode materials.

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