A method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis
By combining room-temperature electrophoretic deposition with sintering, the problems of insufficient density and bonding strength of TiB2 coatings were solved, achieving low-cost and high-efficiency TiB2 coating preparation, which is suitable for aluminum electrolysis processes and improves the density and bonding strength of the coating.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHENGZHOU UNIV
- Filing Date
- 2026-01-29
- Publication Date
- 2026-06-09
AI Technical Summary
Existing methods for preparing TiB2 coatings suffer from problems such as insufficient coating density, low bonding strength, and high process costs. In particular, the utilization efficiency of TiB2 is low and it is difficult to recover in the high-temperature molten salt electrophoretic deposition method, which leads to increased preparation costs.
A method combining room-temperature electrophoretic deposition and sintering was adopted to form a coating on the surface of a graphite cathode by electrophoretic deposition of TiB2 particles, and combined with high-temperature sintering and impregnation treatment to improve the density and bonding strength of the coating.
A TiB2 coating with high density and high bonding strength was prepared, which significantly reduced the raw material cost, improved the utilization efficiency of TiB2, and ensured the long-term stability of the coating in the electrolytic environment.
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Figure CN122169165A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of aluminum electrolysis cathode material preparation technology, and specifically discloses a method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis. Background Technology
[0002] In aluminum electrolysis, the wetting properties between the cathode material and molten aluminum are one of the core factors determining the operating efficiency of the electrolytic cell. Traditional graphite or carbon cathodes have poor wettability to molten aluminum, resulting in discontinuous droplets of molten aluminum on the cathode surface, forming an unstable solid-liquid interface. This interfacial instability causes violent fluctuations in the molten aluminum, forcing the electrolytic cell to maintain a thicker layer of molten aluminum to mitigate these fluctuations. This necessitates a higher electrode spacing to prevent short circuits between the anode and cathode, leading to increased cell voltage and energy consumption. Using a wettable cathode, the molten aluminum can form a continuous and stable liquid film on the cathode surface. This excellent wettability allows only a thin layer of molten aluminum to form a stable electrode interface, thereby shortening the electrode spacing and reducing cell voltage. Furthermore, wettable cathode materials exhibit good resistance to electrolytes and impurities, reducing corrosion or structural damage caused by the penetration of impurities such as molten salts and sodium into the cathode substrate. Therefore, wettable cathode technology is considered a key direction for solving the problems of high energy consumption and high carbon emissions in traditional aluminum electrolysis.
[0003] Currently, using TiB2 as the coating for graphite cathodes is the most promising method for industrial application. Various processes have been proposed for preparing TiB2-coated wettable cathodes, with mainstream methods including coating, plasma spraying, and vapor deposition. Coating involves directly applying a slurry containing TiB2 particles to the surface of the graphite cathode, followed by high-temperature treatment to form the coating. Plasma spraying uses a plasma flame to rapidly melt TiB2 powder and deposit it onto the substrate surface. Vapor deposition forms a TiB2 coating on the graphite substrate surface through physical or chemical reactions in the gas phase. However, these methods generally suffer from insufficient coating density, low bonding strength with the substrate, and high process costs, making it difficult to balance economic efficiency with coating quality.
[0004] High-temperature molten salt electrophoretic deposition has been applied to the preparation of TiB2 coatings in recent years. This method involves driving TiB2 particles to deposit and sinter densely onto the cathode in a high-temperature molten salt system using an electric field. Compared to previous coating and spraying methods, it can achieve coatings with higher bonding strength and denser structure to a certain extent. For example, patents CN115094499A, CN114045546A, and CN112359395A all employ molten salt electrophoretic deposition. Under high temperature and inert atmosphere protection, by controlling the molten salt composition, temperature, and electric field conditions, the deposition and sintering of metal boride nanoparticles on the substrate surface are carried out simultaneously, resulting in coatings with high density and strong adhesion. However, TiB2 is an expensive raw material, and high-temperature molten salt electrophoretic deposition requires a high TiB2 concentration, but the actual amount deposited on the electrode surface is very small, resulting in extremely low utilization efficiency. Furthermore, some TiB2 particles tend to agglomerate under the influence of the electric field and precipitate at the bottom of the molten salt. These problems result in a significant amount of TiB2 being lost in the molten salt, making it difficult to effectively recover and recycle, thus substantially increasing the overall preparation cost. Therefore, improving the utilization efficiency of TiB2 in the coating preparation process is key to reducing preparation costs.
[0005] Compared to high-temperature molten salt electrophoretic deposition, coating preparation technology based on a combination of room-temperature electrophoretic deposition and sintering is more economical. Room-temperature electrophoretic deposition is typically a process of particle deposition in an organic solvent at room temperature. The deposited particles are easily separated from the solvent and can be almost entirely recovered, resulting in extremely high utilization efficiency of TiB2. Currently, coating preparation technology combining room-temperature electrophoretic deposition and sintering has been applied to the preparation of Ti2AlC corrosion-resistant coatings (CN110373700A), SiC coatings (CN101423422A), and SiC-Al2O3 composite coatings (CN119020782A). However, how to prepare graphite cathodes with TiB2 coatings using room-temperature electrophoretic deposition methods is currently undisclosed, and there is a lack of related technical reports on how to obtain TiB2 coatings with high density and high bonding strength. Summary of the Invention
[0006] To address the shortcomings of existing technologies, this invention provides a method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis. This method can achieve the preparation of a titanium diboride coating on the surface of the graphite cathode for aluminum electrolysis, with low process cost and high coating quality.
[0007] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution: A method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis includes the following steps: S1. The surface of the graphite cathode is polished, cleaned and dried to obtain a pretreated graphite cathode; S2. Add TiB2 powder and dispersant to the dispersion medium, and disperse by ultrasonication or mechanical stirring to obtain a TiB2 suspension; S3. Place the pretreated graphite cathode described in step S1 into the TiB2 suspension described in step S2 for electrophoretic deposition, remove and dry it after deposition to obtain a TiB2 deposited graphite cathode. S4. The TiB2 deposited graphite cathode obtained in step S3 is sintered at high temperature in a protective atmosphere to obtain a TiB2 coated graphite cathode; S5. The TiB2-coated graphite cathode described in step S4 is impregnated to allow the impregnating agent to fully penetrate into the pores of the coating. After impregnation, it is removed and dried to obtain the impregnated TiB2-coated graphite cathode. S6. The TiB2-coated graphite cathode that has been impregnated in step S5 is subjected to a second high-temperature sintering to finally obtain a TiB2-coated graphite cathode with high density and high bonding strength.
[0008] Preferably, the concentration of TiB2 powder in step S2 is 1-20 g / L, and the powder particle size ranges from 0.1-10 μm.
[0009] Preferably, in step S2, the TiB2 powder adopts a composite particle size, which is a mixture of large and small particles. The large particles have a diameter of 1-10 μm, the small particles have a diameter of 0.1-1 μm, and the mass ratio of large particles to small particles is (2-4):1.
[0010] Preferably, in step S2, the dispersant is one or more of polyethyleneimine, polyacrylamide, polylysine, or chitosan; and the dispersion medium is one or more of ethanol, isopropanol, acetone, or n-butanol.
[0011] Preferably, the conditions for electrophoretic deposition in step S3 are: deposition voltage of 10-200V and deposition time of 5-30min.
[0012] Preferably, in step S3, the electrophoretic deposition is performed on a magnetic stirrer at a speed of 100-600 r / min.
[0013] Preferably, the electrophoretic deposition and drying process in step S3 is repeated 1-5 times.
[0014] Preferably, in step S4, the sintering temperature is 800-1500℃, the heating rate is 1-5℃ / min, the holding time is 1-3h, and the protective atmosphere is argon or a mixture of hydrogen and argon.
[0015] Preferably, the high-temperature sintering in step S4 adopts a two-stage heating method: in the first stage, the temperature is raised to 600-900℃ at a heating rate of 1-3℃ / min and held for 0.5-2h; in the second stage, the temperature is raised to 900-1500℃ at a heating rate of 2-5℃ / min and held for 1-3h.
[0016] Preferably, the impregnation process in step S5 employs alternating vacuum and pressurized impregnation; wherein the vacuum degree is -0.08 to -0.1 MPa, the pressure is 0.5 to 2.0 MPa, and the impregnation time is 10 to 90 minutes.
[0017] Preferably, the impregnating agent in step S5 is one of coal tar pitch, petroleum coke pitch, or phenolic resin.
[0018] Preferably, the secondary sintering temperature in step S6 is 800-1200℃, and the holding time is 1-3h.
[0019] The beneficial effects of this invention are as follows: This invention proposes a method for preparing a titanium diboride-coated graphite cathode for aluminum electrolysis. By combining electrophoretic deposition of TiB2 particles, sintering, and impregnation processes, a low-cost, high-quality TiB2 coating is prepared on the graphite cathode surface. Compared with existing technologies, this invention employs a room-temperature electrophoretic deposition method. During the deposition process, magnetic stirring maintains uniform particle suspension, reducing agglomeration and precipitation. The utilization rate of TiB2 particles in the suspension is high, and undeposited particles can be recycled, significantly reducing raw material costs and avoiding the waste of raw materials caused by high-temperature molten salt methods. Furthermore, sintering ensures a strong bond between the TiB2 particles and the graphite substrate, effectively improving the bonding strength between the coating and the substrate. Finally, the impregnation process, through the penetration of the impregnating agent into the coating pores and subsequent heat treatment, strengthens the bonding strength between the coating and the substrate while significantly improving the coating's density. The selected impregnating agent can carbonize to form a stable carbon structure during subsequent aluminum electrolysis, without introducing harmful impurities or causing secondary problems, and without affecting its wettability, ensuring the long-term stability of the coating in the electrolytic environment. Attached Figure Description
[0020] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.
[0021] Figure 1 This is a process flow diagram of a method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to the present invention. After electrophoretic deposition, sintering, and impregnation processes, a TiB2 coated graphite cathode with high density and high bonding strength was obtained.
[0022] Figure 2 This is an image of the TiB2-coated graphite cathode with high density and high bonding strength obtained in Example 1 after being polished with 400-mesh SiC sandpaper. Detailed Implementation
[0023] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. Example 1:
[0024] S1. The surface of the graphite cathode is polished, cleaned and dried to obtain a pretreated graphite cathode.
[0025] S2. Select large TiB2 powder particles with a particle size of 5 μm and small TiB2 powder particles with a particle size of 0.5 μm, and mix them at a mass ratio of 3:1. Add the mixed powder to the dispersion medium ethanol at a concentration of 10 g / L, add the dispersant polyethyleneimine, and disperse by ultrasonication for 30 min to obtain a stable TiB2 suspension.
[0026] S3. The pretreated graphite cathode was placed in a TiB2 suspension and electrophoretically deposited on a magnetic stirrer at a speed of 300 r / min. The deposition voltage was 100 V and the deposition time was 15 min. After deposition, the cathode was removed and dried. This deposition and drying process was repeated 3 times to obtain a TiB2 deposited graphite cathode.
[0027] S4. The TiB2-deposited graphite cathode was placed in a tube furnace and sintered under an argon protective atmosphere. A two-stage heating method was adopted: in the first stage, the temperature was increased to 800℃ at a rate of 2℃ / min and held for 1 hour; in the second stage, the temperature was increased to 1300℃ at a rate of 3℃ / min and held for 2 hours to obtain the TiB2-coated graphite cathode.
[0028] S5. Place the TiB2-coated graphite cathode in the impregnating agent coal tar pitch, first evacuate to -0.09MPa and hold for 15min, then pressurize to 1.0MPa and hold for 30min, remove and dry after impregnation to obtain the impregnated TiB2-coated graphite cathode.
[0029] S6. The impregnated TiB2-coated graphite cathode is subjected to a second high-temperature sintering at 1000℃ and held at that temperature for 2 hours to finally obtain a TiB2-coated graphite cathode with high density and high bonding strength.
[0030] Scanning electron microscopy and scratch test analysis showed that the density of the TiB2 coated graphite cathode was 98.5% and the bonding strength was 28.5 MPa.
[0031] Example 2: S1. The surface of the graphite cathode is polished, cleaned and dried to obtain a pretreated graphite cathode.
[0032] S2. Select TiB2 powder with a single particle size of 0.1 μm, add it to the dispersion medium isopropanol at a concentration of 1 g / L, add dispersant polyacrylamide, and disperse by ultrasonication for 30 min to obtain a stable TiB2 suspension.
[0033] S3. The pretreated graphite cathode was placed in a TiB2 suspension and electrophoretically deposited on a magnetic stirrer at a speed of 100 r / min. The deposition voltage was 10V and the deposition time was 30 min. After deposition, the cathode was removed and dried. This deposition and drying process was repeated once to obtain a TiB2 deposited graphite cathode.
[0034] S4. The TiB2-deposited graphite cathode was placed in a tube furnace and sintered under a protective atmosphere of hydrogen and argon mixture. The temperature was increased to 800℃ at a rate of 5℃ / min and held for 1 hour to obtain the TiB2-coated graphite cathode.
[0035] S5. Place the TiB2-coated graphite cathode in the impregnating agent phenolic resin, first evacuate to -0.08MPa and hold for 30 min, then pressurize to 0.5MPa and hold for 60 min, remove and dry after impregnation to obtain the impregnated TiB2-coated graphite cathode.
[0036] S6. The impregnated TiB2-coated graphite cathode is subjected to a second high-temperature sintering at 800℃ and held for 3 hours to finally obtain a TiB2-coated graphite cathode with high density and high bonding strength.
[0037] Scanning electron microscopy and scratch test analysis showed that the density of the TiB2 coated graphite cathode was 92% and the bonding strength was 18.2 MPa. Example 3:
[0038] S1. The surface of the graphite cathode is polished, cleaned and dried to obtain a pretreated graphite cathode.
[0039] S2. Select large TiB2 powder particles with a particle size of 10 μm and small TiB2 powder particles with a particle size of 1 μm, and mix them at a mass ratio of 4:1. Add the mixed powder to the dispersion medium acetone at a concentration of 20 g / L, add the dispersant polylysine, and disperse by ultrasonication for 30 min to obtain a stable TiB2 suspension.
[0040] S3. The pretreated graphite cathode was placed in a TiB2 suspension and electrophoretically deposited on a magnetic stirrer at a speed of 600 r / min. The deposition voltage was 200 V and the deposition time was 5 min. After deposition, the cathode was removed and dried. This deposition and drying process was repeated 5 times to obtain a TiB2 deposited graphite cathode.
[0041] S4. The TiB2-deposited graphite cathode was placed in a tube furnace and sintered under an argon protective atmosphere. The temperature was increased to 1500℃ at a rate of 1℃ / min and held for 3 hours to obtain the TiB2-coated graphite cathode.
[0042] S5. Place the TiB2-coated graphite cathode in the impregnating agent phenolic resin, first evacuate to -0.1MPa and hold for 10 min, then pressurize to 2MPa and hold for 10 min, remove and dry after impregnation to obtain the impregnated TiB2-coated graphite cathode.
[0043] S6. The impregnated TiB2-coated graphite cathode is subjected to a second high-temperature sintering at 1200℃ and held for 1 hour to finally obtain a TiB2-coated graphite cathode with high density and high bonding strength.
[0044] Scanning electron microscopy and scratch test analysis showed that the density of the TiB2 coated graphite cathode was 98.7% and the bonding strength was 28.9 MPa. Example 4:
[0045] S1. The surface of the graphite cathode is polished, cleaned and dried to obtain a pretreated graphite cathode.
[0046] S2. Select TiB2 powder with a single particle size of 2μm, add it to the dispersion medium n-butanol at a concentration of 8g / L, add chitosan as a dispersant, and disperse it by ultrasonication for 30min to obtain a stable TiB2 suspension.
[0047] S3. The pretreated graphite cathode was placed in a TiB2 suspension and electrophoretically deposited on a magnetic stirrer at a speed of 400 r / min. The deposition voltage was 80 V and the deposition time was 20 min. After deposition, the cathode was removed and dried. This deposition and drying process was repeated twice to obtain a TiB2 deposited graphite cathode.
[0048] S4. The TiB2-deposited graphite cathode was placed in a tube furnace and sintered under an argon protective atmosphere. A two-stage heating method was adopted: in the first stage, the temperature was increased to 900℃ at a rate of 2℃ / min and held for 0.5h; in the second stage, the temperature was increased to 1200℃ at a rate of 3℃ / min and held for 1.5h to obtain the TiB2-coated graphite cathode.
[0049] S5. Place the TiB2-coated graphite cathode in the impregnating agent coal tar pitch, first evacuate to -0.09MPa and hold for 30 min, then pressurize to 1.5MPa and hold for 30 min, remove and dry after impregnation to obtain the impregnated TiB2-coated graphite cathode.
[0050] S6. The impregnated TiB2-coated graphite cathode is subjected to a second high-temperature sintering at 1100℃ and held for 2 hours to finally obtain a TiB2-coated graphite cathode with high density and high bonding strength.
[0051] Scanning electron microscopy and scratch test analysis showed that the density of the TiB2 coated graphite cathode was 96.5% and the bonding strength was 24.8 MPa. Example 5:
[0052] S1. The surface of the graphite cathode is polished, cleaned and dried to obtain a pretreated graphite cathode.
[0053] S2. Select large TiB2 powder particles with a particle size of 8 μm and small TiB2 powder particles with a particle size of 0.8 μm, and mix them at a mass ratio of 2:1. Add the mixed powder to a dispersion medium of ethanol and isopropanol (volume ratio 1:1) at a concentration of 15 g / L, add a mixture of polyethyleneimine and polyacrylamide as a dispersant, and ultrasonically disperse for 30 min to obtain a stable TiB2 suspension.
[0054] S3. The pretreated graphite cathode was placed in a TiB2 suspension and electrophoretically deposited on a magnetic stirrer at a speed of 500 r / min. The deposition voltage was 150 V and the deposition time was 10 min. After deposition, the cathode was removed and dried. This deposition and drying process was repeated 4 times to obtain a TiB2 deposited graphite cathode.
[0055] S4. The TiB2-deposited graphite cathode was placed in a tube furnace and sintered under an argon protective atmosphere. The temperature was increased to 1400℃ at a rate of 3℃ / min and held for 2 hours to obtain the TiB2-coated graphite cathode.
[0056] S5. Place the TiB2-coated graphite cathode in the impregnating agent phenolic resin, first evacuate to -0.095MPa and hold for 20min, then pressurize to 1.2MPa and hold for 40min, remove and dry after impregnation to obtain the impregnated TiB2-coated graphite cathode.
[0057] S6. The impregnated TiB2-coated graphite cathode is subjected to a second high-temperature sintering at 900℃ and held at that temperature for 2.5h to finally obtain a TiB2-coated graphite cathode with high density and high bonding strength.
[0058] Scanning electron microscopy and scratch test analysis showed that the density of the TiB2 coated graphite cathode was 97.8% and the bonding strength was 27.2 MPa. Example 6:
[0059] S1. The surface of the graphite cathode is polished, cleaned and dried to obtain a pretreated graphite cathode.
[0060] S2. Select large TiB2 powder particles with a particle size of 5 μm and small TiB2 powder particles with a particle size of 0.5 μm, and mix them at a mass ratio of 3:1. Add the mixed powder to the dispersion medium ethanol at a concentration of 10 g / L, add the dispersant polyethyleneimine, and disperse by ultrasonication for 30 min to obtain a stable TiB2 suspension.
[0061] S3. The pretreated graphite cathode was placed in a TiB2 suspension and electrophoretically deposited on a magnetic stirrer at a speed of 300 r / min. The deposition voltage was 100 V and the deposition time was 15 min. After deposition, the cathode was removed and dried. This deposition and drying process was repeated 3 times to obtain a TiB2 deposited graphite cathode.
[0062] S4. The TiB2-deposited graphite cathode was placed in a tube furnace and sintered under an argon protective atmosphere. A two-stage heating method was adopted: in the first stage, the temperature was increased to 800℃ at a rate of 2℃ / min and held for 1 hour; in the second stage, the temperature was increased to 1300℃ at a rate of 3℃ / min and held for 2 hours to obtain the TiB2-coated graphite cathode.
[0063] Scanning electron microscopy and scratch test analysis showed that the density of the TiB2 coated graphite cathode was 82.3% and the bonding strength was 12.5 MPa.
Claims
1. A method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis, characterized in that, Includes the following steps: S1. The surface of the graphite cathode is polished, cleaned and dried to obtain a pretreated graphite cathode; S2. Add TiB2 powder and dispersant to the dispersion medium, and disperse by ultrasonication or mechanical stirring to obtain a TiB2 suspension; S3. Place the pretreated graphite cathode described in step S1 into the TiB2 suspension described in step S2 for electrophoretic deposition, remove and dry it after deposition to obtain a TiB2 deposited graphite cathode. S4. The TiB2 deposited graphite cathode obtained in step S3 is sintered at high temperature in a protective atmosphere to obtain a TiB2 coated graphite cathode; S5. The TiB2-coated graphite cathode described in step S4 is impregnated to allow the impregnating agent to fully penetrate into the pores of the coating. After impregnation, it is removed and dried to obtain the impregnated TiB2-coated graphite cathode. S6. The TiB2-coated graphite cathode that has been impregnated in step S5 is subjected to a second high-temperature sintering to finally obtain a TiB2-coated graphite cathode with high density and high bonding strength.
2. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claim 1, characterized in that, In step S2, the concentration of TiB2 powder is 1-20 g / L, and the powder particle size ranges from 0.1-10 μm.
3. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claims 1 and 2, characterized in that, In step S2, the TiB2 powder adopts a compound particle size, which is a mixture of large and small particles; wherein the particle size of the large particles is 1-10μm, the particle size of the small particles is 0.1-1μm, and the mass ratio of the large particles to the small particles is (2-4):
1.
4. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claim 1, characterized in that, In step S2, the dispersant is one or more of polyethyleneimine, polyacrylamide, polylysine, or chitosan; the dispersion medium is one or more of ethanol, isopropanol, acetone, or n-butanol.
5. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claim 1, characterized in that, The conditions for electrophoretic deposition in step S3 are: deposition voltage of 10-200V and deposition time of 5-30min.
6. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claim 1, characterized in that, In step S3, electrophoretic deposition is carried out on a magnetic stirrer at a speed of 100-600 r / min.
7. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claim 1, characterized in that, The electrophoretic deposition and drying process in step S3 is repeated 1-5 times.
8. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claim 1, characterized in that, In step S4, the sintering temperature is 800-1500℃, the heating rate is 1-5℃ / min, the holding time is 1-3h, and the protective atmosphere is either argon or a mixture of hydrogen and argon.
9. A method for preparing a titanium diboride-coated graphite cathode for aluminum electrolysis according to claims 1 and 8, characterized in that, In step S4, the high-temperature sintering adopts a two-stage heating method: in the first stage, the temperature is raised to 600-900℃ at a heating rate of 1-3℃ / min and held for 0.5-2h; in the second stage, the temperature is raised to 900-1500℃ at a heating rate of 2-5℃ / min and held for 1-3h.
10. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claim 1, characterized in that, The impregnation process in step S5 employs alternating vacuum and pressure impregnation; wherein the vacuum degree is -0.08 to -0.1 MPa, the pressure is 0.5 to 2.0 MPa, and the impregnation time is 10 to 90 minutes.
11. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claim 1, characterized in that, In step S5, the impregnating agent is one of coal tar pitch, petroleum coke pitch, or phenolic resin.
12. The method for preparing a titanium diboride coated graphite cathode for aluminum electrolysis according to claim 1, characterized in that, In step S6, the secondary sintering temperature is 800-1200℃, and the holding time is 1-3h.