TiMn alloy anode material, preparation method and application thereof

Abstract

The application discloses a TiMn alloy anode material and a preparation method and application thereof. The preparation method is as follows: a titanium substrate surface is coated with a manganese-containing slurry to obtain a TiMn green blank; the TiMn green blank is subjected to low-temperature degreasing and dehydrogenation under high-vacuum conditions at not more than 600 DEG C, then argon is filled in to be heated to not more than 800 DEG C under the protection of an atmosphere for medium-temperature manganese infiltration, and then the temperature is continuously increased to above 850 DEG C for high-temperature manganese infiltration to obtain a TiMn-Ti plate; the TiMn-Ti plate is soaked in an acid solution and then washed to obtain the TiMn alloy anode material. The TiMn alloy anode material has the advantages of high manganese content, strong passivation resistance, good acid corrosion resistance, good strength and ductility, etc. When the TiMn alloy anode material is used as an anode to electrolytically prepare MnO2, the loss of the anode plate during mechanical stripping of the MnO2 can be greatly reduced, the problems of the existing electrolytic MnO2 crystal form and purity being limited by electrolysis conditions and the MnO2 plate being broken during mechanical stripping of the MnO2 in the later period are solved, and the quality and production efficiency of the MnO2 are greatly improved.

Description

Technical Field

[0001] This invention relates to an anode material, specifically a TiMn alloy anode material, and also to its preparation method and application, belonging to the technical field of electrode material preparation and electrolytic MnO2 industrial technology. Background Technology

[0002] Compared to chemically produced MnO2 and natural manganese dioxide, electrolytic MnO2 possesses advantages such as high purity, strong adsorption, strong hygroscopicity and oxidizing properties, high activity, and excellent discharge performance, making it a key component in the cathode materials of modern alkaline, lithium, and sodium batteries. Electrolytic MnO2 exhibits a relatively complex crystal structure, including five main crystal types (α, β, γ, etc.) and over 30 secondary crystal types. The electrochemical performance of electrolytic MnO2 varies significantly depending on its crystal form and purity, primarily related to crystal size, lattice defect density, and degree of hydration. Generally, the activity of MnO2 increases with the increase of its water of crystallization content. Water of crystallization promotes proton diffusion in the solid phase, and γ-MnO2 exhibits the best activity among various crystal forms of MnO2.

[0003] Currently, the main method for producing electrolytic MnO2 is the high-temperature electrolysis method, which refers to the electrolysis of an electrolyte system of MnSO4-H2SO4 at a high temperature (96-98℃) and a certain current density, so that Mn... 2+ A redox reaction occurs on the anode, precipitating and depositing MnO2. Once the MnO2 has reached a certain thickness, the anode can be removed from the tank, and the MnO2 is mechanically stripped away. The main factors affecting the electrolytic synthesis of MnO2 and the properties of the final product in this process are electrolysis temperature, electrolyte composition, anode current density, and anode material. To ensure the MnO2... 2+ To overcome the reverse potential diffusion to the anode and facilitate MnO2 precipitation, electrolysis is generally carried out by heating the electrolyte to a temperature as high as possible below its boiling point. Acidity and current density have a significant impact on the crystal structure and purity of electrolyzed MnO2, but the current settings for acidity and current density are often limited by the corrosion resistance and passivation resistance of the anode material. Furthermore, mechanical stripping of MnO2 causes significant wear on the anode, requiring anodes with high strength and ductility.

[0004] The electrolytic MnO2 industry has developed to the point where various anodes have been used and researched, including graphite anodes, lead anodes, pure titanium anodes, alloy anodes, and Ti-based coated anodes. Currently, pure Ti anodes and Ti-based TiMn coated anodes are mainly used. Pure titanium anodes have high mechanical strength, corrosion resistance, low specific gravity, and good electrical properties, but they are prone to passivation under high current density and high acidity electrolysis environments. This not only leads to increased cell voltage and energy consumption but also increases the frequency of cell removal, reducing production efficiency. Compared to pure titanium anodes, Ti-based TiMn coated anodes retain the excellent comprehensive mechanical properties provided by the pure Ti matrix, while also offering better wettability, lower cell voltage, and better resistance to passivation. Patent CN101694001A discloses a method for preparing a TiMn-coated anode plate with a surface Mn content of 20-35% and good metallurgical bonding through high-temperature diffusion at 900-1300℃. However, the surface Mn content of the anode plate prepared by this method is limited, resulting in limited performance of the final anode plate. Furthermore, the high reaction diffusion temperature of this method not only leads to high energy consumption but also significantly damages the mechanical properties of the material itself. Patent CN105887133A discloses a method for preparing a high-deformation-resistance titanium anode for electrolytic manganese dioxide production. This method involves heat-treating a titanium plate in a vacuum environment followed by sandblasting or shot peening to obtain a titanium plate with high strength, deformation resistance, and a certain degree of ductility. However, the problems of high tank pressure and easy passivation of pure titanium plates remain unresolved. The reason for the easy passivation of pure Ti is that its oxide has extremely poor conductivity, while Mn oxide has good conductivity. Therefore, increasing the Mn content in the TiMn coating can improve the passivation resistance. However, Mn has a very high vapor pressure at high temperatures, at 10 -2 Under vacuum conditions, Mn begins to volatilize at approximately 750℃, resulting in low Mn potential during high-temperature diffusion, difficulty in manganese diffusion, and low Mn content. Furthermore, the significant volatilization of the Mn source leads to low material utilization and contamination of the furnace and vacuum system. In addition, high diffusion temperatures cause coarse αTi grains in the Ti matrix, resulting in β-titanium transformation. Upon cooling, a lamellar β-titanium transformation structure is obtained. While this increases the strength of the plate, it also increases brittleness, making it prone to breakage during mechanical stripping of MnO2. Currently, to ensure sufficient manganese diffusion on the TiMn anode surface, high strength and ductility, and to prevent excessive Mn source volatilization, a compromise is made in the TiMn plate preparation process: short-term holding at high temperatures. This results in insufficient manganese diffusion and mechanical properties in the TiMn plate.

[0005] The rapid development of new energy sources has placed demands on improving the quality and energy efficiency of electrolytic MnO2, a crucial raw material for batteries. Currently, the anode materials used in MnO2 electrolysis are difficult to apply under high acidity and high current conditions, resulting in low electrolysis efficiency, a limited range for MnO2 crystal form control, low purity, and narrow performance control. Therefore, there is an urgent need to develop new anode materials to improve their overall performance, efficiently produce high-quality electrolytic MnO2, and contribute to the development of the new energy industry. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the first objective of this invention is to provide a TiMn alloy anode material. This anode material possesses advantages such as high manganese content, strong resistance to passivation, good acid corrosion resistance, and good strength and ductility.

[0007] The second objective of this invention is to provide a method for preparing TiMn alloy anode materials. This method is simple, low-cost, and suitable for large-scale industrial production.

[0008] The third objective of this invention is to provide an application of a TiMn alloy anode material. When used as an anode in the electrolytic preparation of MnO2, this TiMn alloy anode material can adapt to electrolytic environments with high acidity and high current density, thus solving the problem that the crystal form and purity of existing electrolytic MnO2 are limited by electrolytic conditions. Simultaneously, its high strength and good ductility can significantly reduce the problem of TiMn anode plate breakage during the subsequent mechanical stripping of MnO2, thereby improving MnO2 production efficiency and reducing its energy consumption and material loss.

[0009] To achieve the above-mentioned technical objectives, the present invention provides a method for preparing TiMn alloy anode material. The method involves coating a titanium substrate with a manganese-containing slurry to obtain a TiMn green blank; subjecting the TiMn green blank to low-temperature degreasing and dehydrogenation under high vacuum conditions not exceeding 600°C; then introducing an inert gas and heating to not exceeding 800°C for medium-temperature manganese infiltration; and further heating to above 850°C for high-temperature manganese infiltration to obtain a TiMn-Ti plate; and finally washing the TiMn-Ti plate after immersion in an acid solution to obtain the final product.

[0010] The present invention mainly designs the gas pressure value based on the vapor pressure data of Mn at different temperatures to prevent manganese volatilization, reduce raw material loss and equipment damage, and also make manganese have a higher manganese potential when diffusing into Ti at high temperature, reduce sintering temperature, reduce energy consumption, increase manganese content in Ti plate, and achieve two-step diffusion through segmented manganese diffusion, thereby improving the diffusion and penetration efficiency of manganese. Specifically, it includes: (1) placing TiMn green billet under high vacuum conditions for low-temperature dehydrogenation and degreasing, removing the added dispersant, and dehydrogenating the surface of hydrogenated titanium plate to expose the active titanium surface to ensure subsequent manganese diffusion; then filling in inert gas to increase the gas pressure in the furnace, which can make heat transfer better, temperature uniform, and shorten the holding time. On the one hand, it ensures the activity of Ti plate and Mn powder, and on the other hand, it can increase the Mn potential and strengthen diffusion without Mn volatilization. Under this pressure condition, medium-temperature manganese diffusion is carried out first, which can form a sintering neck between Ti matrix and Mn powder and between Mn particles, forming a diffusion channel for pre-diffusion. This step ensures that a small amount of shrinkage occurs when sintering necks are formed between the Ti plate and Mn powder particles and between Mn powder particles, preventing relative movement between the Ti plate and Mn powder due to the difference in shrinkage (the Mn powder layer shrinks more during sintering, while the Ti plate does not shrink), hindering the formation of sintering necks between the Ti plate and Mn powder particles, which is not conducive to the diffusion of Mn into Ti. It also prevents the Mn layer from densifying too quickly at high temperatures, which reduces the surface diffusion channels for rapid atomic diffusion, providing a large number of surface diffusion channels for high-speed atomic diffusion in subsequent high-temperature diffusion, and promoting manganese diffusion; (2) High-temperature manganese diffusion is carried out, which can further promote the rapid diffusion of Mn under high-temperature conditions, form a diffusion layer, and increase the amount of manganese diffusion.

[0011] As a preferred embodiment, the titanium substrate undergoes a pretreatment including sandblasting and oxalic acid surface hydrogenation.

[0012] Sandblasting the titanium substrate surface increases the surface energy of the Ti plate, refines the Ti plate surface grains, and increases grain boundaries. This allows Mn atoms to diffuse more rapidly into the Ti plate along the grain boundaries during the high-temperature manganese diffusion process. At the same time, sandblasting also removes the oxide layer and contaminants on the Ti plate surface, increasing surface roughness and facilitating the adhesion of the slurry during subsequent Mn coating. Oxalic acid hydrogenation treatment of the titanium plate surface forms hydrides on the Ti surface, enabling the Ti plate to achieve a highly active Ti plate surface through dehydrogenation during the heating process. This is beneficial for the reaction and diffusion of Mn and Ti during the subsequent high-temperature manganese diffusion process, thus promoting manganese diffusion.

[0013] As a preferred embodiment, the titanium substrate is a TA1 type titanium plate or a TA2 type titanium plate. The thickness of the titanium substrate is 1.5–2 mm.

[0014] As a preferred embodiment, the oxalic acid has a mass concentration of 5% to 15%. Oxalic acid is a weak organic acid with good safety profile, and its reaction with Ti is easily controlled.

[0015] As a preferred embodiment, the oxalic acid surface hydrogenation treatment process is as follows: boiling the oxalic acid solution for 3-5 minutes, and then immersing it in a titanium plate for 40-60 minutes.

[0016] As a preferred embodiment, the pretreatment process is as follows: the titanium substrate is sequentially cut into pieces, sandblasted, washed, subjected to oxalic acid surface hydrogenation treatment, washed, and dried.

[0017] As a preferred embodiment, the manganese-containing slurry comprises manganese powder and an organic dispersant.

[0018] As a preferred embodiment, the particle size of the manganese powder is 10–80 μm.

[0019] As a preferred embodiment, the organic dispersant is either a water-soluble organic dispersant or a non-water-soluble organic dispersant. A non-water-soluble organic dispersant is more preferred. Water-soluble organic dispersants include gum arabic solutions, polyvinyl alcohol solutions, etc. Non-water-soluble organic dispersants include polyvinyl butyral organic solutions, etc.

[0020] As a preferred embodiment, the organic dispersant is a polyvinyl butyral ethanol solution. Using a non-water-soluble organic dispersant (such as a polyvinyl butyral ethanol solution) can prevent the Mn powder from being oxidized during the preparation process.

[0021] As a preferred embodiment, the organic dispersant is a mixture of ethanol and polyvinyl butyral.

[0022] As a preferred embodiment, the mass ratio of ethanol to polyvinyl butyral is 8:1 to 4.

[0023] As a preferred embodiment, the mass ratio of manganese powder to organic dispersant is 0.2 to 2:1.

[0024] As a preferred embodiment, the preparation process of the manganese-containing slurry is as follows: manganese powder and an organic dispersant are stirred and mixed, followed by vacuum degassing to obtain a suspension slurry. The stirring and mixing is preferably ultrasonic stirring. Ultrasonic stirring ensures that the Mn powder is fully and uniformly dispersed. Vacuum degassing is mainly to remove oxygen from the slurry, preventing the Mn powder from oxidizing during slurry preparation and Mn coating. It also prevents air bubbles from forming in the Mn coating layer during the Mn coating process and subsequent vacuuming, thus ensuring the integrity and uniformity of the Mn coating layer.

[0025] As a preferred option, the coating method is either scraping or spraying.

[0026] As a preferred embodiment, the coating thickness is 100–300 μm. Controlling the coating thickness within a suitable range is beneficial for obtaining high-performance TiMn alloy materials. If the coating thickness is too small, there may be insufficient Mn source, while if the coating thickness is too large, Mn powder will be wasted.

[0027] As a preferred embodiment, after coating with the manganese-containing slurry, the material is subjected to static drying and vacuum drying. The static drying time is 30–60 minutes. The vacuum drying temperature is 60–80°C, and the time is 1–2 hours.

[0028] As a preferred embodiment, the low-temperature degreasing and dehydrogenation process is as follows: at 10 -4 ~10 -2 Under vacuum pressure, the temperature is first maintained at 100–120℃ for 0.5–1 h, then at 350–550℃ for 2–4 h, and finally at 550–600℃ for 1–2 h. During this low-temperature treatment, the 100–120℃ temperature condition is the dehydration stage, mainly removing moisture and gas adsorbed during the transfer process; the 350–550℃ temperature condition is the degreasing stage, where organic dispersants (such as PVB) begin to decompose around 350℃ and are essentially decomposed by 550℃; the 350–600℃ temperature condition is the dehydrogenation stage, which decomposes the thin titanium hydride layer on the Ti plate surface to form a highly active titanium surface.

[0029] As a preferred embodiment, the inert gas is introduced to a pressure of 1 Pa to 25 kPa. The inert gas is argon. After dehydrogenation is completed, to increase the manganese diffusion rate, a certain amount of inert gas is introduced to a pressure of 1 Pa to 25 kPa based on the saturated vapor pressure data of manganese at medium-high temperature manganese diffusion temperatures. Since nitrogen reacts with Ti at high temperatures to form titanium nitrides, an inert gas is chosen to regulate the pressure.

[0030] As a preferred embodiment, the medium-temperature manganese infiltration process involves holding the material at 750–800℃ for 1–2 hours. Under this temperature condition, medium-temperature diffusion can be carried out to form a sintering neck and diffusion channels. Since the temperature is not high and the connection between materials is mainly point contact, atoms mainly diffuse through the surface, which can reduce the sintering shrinkage of the Mn-coated layer during the formation of the sintering neck, reduce its displacement with the non-shrinking Ti plate, and better form diffusion channels.

[0031] As a preferred embodiment, the high-temperature manganese infiltration process involves holding the temperature at 850–950°C for 2–4 hours. This temperature condition allows for faster diffusion, rapid manganese infiltration, and promotes densification of the manganese coating. Simultaneously, this temperature has minimal impact on the mechanical properties of the Ti substrate, preserving its original ductility.

[0032] As a preferred embodiment, the acid solution is dilute sulfuric acid. Immersion in the acid solution removes excess unreacted pure Mn powder from the sample surface. Furthermore, using dilute sulfuric acid ensures that the manganese infiltration layer is not damaged.

[0033] As a preferred embodiment, the concentration of the dilute sulfuric acid is 0.2–1.5 mol / L.

[0034] This invention also provides a TiMn alloy anode material, which is prepared by the above method. This TiMn alloy anode material has high manganese content, strong resistance to passivation, good acid corrosion resistance, and good strength and ductility.

[0035] This invention also provides an application of TiMn alloy anode material, which is used as an anode for the electrolytic preparation of MnO2. When using this TiMn alloy anode material as an anode for the electrolytic preparation of MnO2, it can adapt to environments with high acidity and high current density, has a large process window, and allows for control over the crystal form and purity of the electrolyzed MnO2.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] (1) By pretreating the Ti plate surface and controlling the manganese diffusion pressure and regulating the manganese diffusion temperature during the segmented manganese diffusion process, the TiMn alloy anode plate material has both high manganese diffusion content, excellent electrical properties and comprehensive mechanical properties. Among them, the hydrogenation and dehydrogenation treatment of the Ti plate surface can make the Ti plate surface have high activity, low pressure and low temperature calcination ensures the activity of the Mn surface, and increasing the gas pressure for medium temperature manganese diffusion can ensure that Mn does not volatilize while strengthening the Mn potential and promoting the diffusion of Mn into the Ti plate. Moreover, the medium temperature pre-diffusion process reduces the shrinkage difference between Mn and Ti, which is conducive to the formation of the sintering neck between the two and provides a fast diffusion channel for high temperature diffusion.

[0038] (2) The reaction pressure value is designed based on the vapor pressure data of Mn at different temperatures. This can prevent manganese volatilization, reduce raw material loss and equipment damage, and also make Mn have a higher manganese potential when diffusing into Ti at high temperatures. This reduces the sintering temperature, reduces energy consumption, increases the Mn content in TiMn alloy anode material, and improves the passivation resistance, acid corrosion resistance, electrical properties and mechanical properties of the plate.

[0039] (4) The preparation method is simple and low in cost, making it suitable for large-scale industrial production;

[0040] (5) When used as an anode for electrolytic preparation of MnO2, it can adapt to the electrolytic environment under high acidity and high current density, and has good strength and ductility. This solves the problems of the crystal form and purity of existing electrolytic MnO2 being limited by electrolytic conditions and the breakage of TiMn anode plates when mechanically peeling off MnO2 in the later stage, thereby improving the production efficiency of MnO2 and reducing its production energy consumption and material loss. Attached Figure Description

[0041] Figure 1 This is a microscopic morphology image of the surface of the TiMn-Ti anode plate prepared in Example 1 of the present invention.

[0042] Figure 2 This is a microscopic morphology diagram of the cross-section of the TiMn-Ti anode plate prepared in Example 1 of the present invention.

[0043] Figure 3 The image shows the XRD pattern of the surface of the TiMn-Ti anode plate prepared in Example 1 of this invention. Detailed Implementation

[0044] The present invention will be further described below with reference to specific examples based on the technical solution of the present invention, but the scope of protection of the present invention is not limited to the following embodiments.

[0045] Example 1

[0046] First, a 1.5mm thick industrial-grade TA1 titanium plate was selected and cut into 40mm × 80mm pieces. The surface of the Ti plate was sandblasted to roughen it, and then washed with water to remove residual dirt. Next, the surface was cleaned with ethanol to remove oil stains, and then washed again with water to remove residue. Then, the treated Ti plate was immersed in a boiling 10% oxalic acid solution for 60 minutes for surface hydrogenation treatment, washed again with water to remove residual acid, and vacuum dried for later use. Then, an organic dispersant was prepared by mixing ethanol and PVB powder at a mass ratio of 8:3 and stirring thoroughly. Electrolytic Mn powder with a particle size of 30μm was selected and mixed with the organic dispersant at a mass ratio of 1:1. The mixture was thoroughly stirred under ultrasonication and then placed in a vacuum chamber for vacuum degassing to form a stable suspension slurry. Next, the gap of the coating device was adjusted to 200 μm, and the obtained slurry was poured onto the surface of the treated Ti plate. A Mn coating layer was evenly coated using a scraper. The coated sample was first allowed to stand and dry for 30 min, and then transferred to a vacuum oven to dry at 80 °C for 1 h. After cooling, the green blank was removed and transferred to a sintering furnace. Under vacuum, it was held at 120 °C for 0.5 h; 350 °C for 1 h; 450 °C for 1 h; 550 °C for 1 h; and then at 600 °C for 0.7 h. After the holding period, argon gas was introduced to a furnace pressure of 1 kPa, and the temperature was raised to 800 °C for 1 h and then 900 °C for 2 h. After the holding period, the plate was cooled and removed from the furnace. Finally, the prepared TiMn-Ti plate was soaked and cleaned with 0.5 mol / L dilute sulfuric acid until no bubbles were generated, and then it was removed, cleaned, and dried to obtain the TiMn-Ti anode plate for electrolytic preparation of MnO2. Testing revealed that the TiMn-Ti anode plate exhibited a tensile strength of 420 MPa, an elongation of 23.3%, and a surface Mn content of 64.2%. Figure 3As shown, the main phase on the electrode surface is TiMn2. For comparison, the 1.5mm thick TA1 Ti plate has a tensile strength of 368MPa and an elongation of 51%.

[0047] The microstructure of the TiMn-Ti anode plate obtained under the conditions of this embodiment was analyzed, such as... Figure 1 and 2 As shown, from Figure 1 As can be seen, the surface of the TiMn-Ti plate is relatively rough, which is conducive to the nucleation and adhesion of MnO2. Furthermore, the rough surface increases the specific surface area, effectively reducing the cell pressure. Figure 2 As can be seen, the manganese-infiltrated layer consists of four layers: a surface manganese-rich layer, an intermediate transition layer, an intermediate needle-like layer, and an inner pure Ti layer.

[0048] Example 2

[0049] First, a 1.5mm thick industrial-grade TA2 titanium plate was selected and cut into 40mm × 80mm pieces. The surface of the Ti plate was sandblasted to roughen it, and then washed with water to remove residual dirt. Next, the surface was cleaned with ethanol to remove oil stains, and then washed again with water to remove residue. Then, the treated Ti plate was immersed in a boiling 10% oxalic acid solution for 50 minutes for surface hydrogenation treatment, washed again with water to remove residual acid, and vacuum dried for later use. Then, an organic dispersant was prepared by mixing ethanol and PVB powder at a mass ratio of 4:1 and stirring thoroughly. Electrolytic Mn powder with a particle size of 20μm was selected and mixed with the organic dispersant at a mass ratio of 0.6:1. The mixture was thoroughly stirred under ultrasonication and then placed in a vacuum chamber for vacuum degassing to form a stable suspension slurry. Next, the gap of the coating device was adjusted to 200 μm, and the obtained slurry was poured onto the surface of the treated Ti plate. A Mn coating layer was evenly coated using a scraper. The coated sample was first allowed to stand and dry for 30 min, and then transferred to a vacuum oven to dry at 80 °C for 1 h. After cooling, the green blank was removed and transferred to a sintering furnace. Under vacuum, it was held at 120 °C for 0.5 h; 350 °C for 1 h; 450 °C for 1 h; 550 °C for 1 h; and then at 600 °C for 0.5 h. After the holding period, argon gas was introduced to a furnace pressure of 10 Pa, and the temperature was raised to 760 °C for 1 h and then 850 °C for 4 h. After the holding period, the plate was cooled and removed from the furnace. Finally, the prepared TiMn-Ti plate was soaked and cleaned with 0.7 mol / L dilute sulfuric acid until no bubbles were generated, and then it was removed, cleaned, and dried to obtain the TiMn-Ti anode plate for electrolytic preparation of MnO2. The above-mentioned TiMn-Ti anode plate was tested and found to have a tensile strength of 403 MPa, an elongation of 27.1%, a surface Mn content of 63.3%, and the main phase on the surface of the plate was TiMn2.

[0050] Example 3

[0051] First, a 1.5mm thick industrial-grade TA1 titanium plate was selected and cut into 40mm × 80mm pieces. The surface of the Ti plate was sandblasted to roughen it, and then washed with water to remove residual dirt. Next, the surface was cleaned with ethanol to remove oil stains, and then washed again with water to remove residue. Then, the treated Ti plate was immersed in a boiling 10% oxalic acid solution for 60 minutes for surface hydrogenation treatment, washed again with water to remove residual acid, and vacuum dried for later use. Then, an organic dispersant was prepared by mixing ethanol and PVB powder at a mass ratio of 2:1 and stirring thoroughly. Electrolytic Mn powder with a particle size of 50μm was selected and mixed with the organic dispersant at a mass ratio of 1.2:1. The mixture was thoroughly stirred under ultrasonication and then placed in a vacuum chamber for vacuum degassing to form a stable suspension slurry. Next, the gap of the coating tool was adjusted to 200 μm, and the obtained slurry was poured onto the surface of the treated Ti plate. A Mn coating layer was evenly coated using a scraper. The coated sample was first allowed to stand and dry for 30 min, and then transferred to a vacuum oven to dry at 80 °C for 1 h. After cooling, the green blank was removed and transferred to a sintering furnace. Under vacuum, it was held at 120 °C for 0.5 h; 350 °C for 1 h; 450 °C for 1 h; 550 °C for 1 h; and then at 600 °C for 0.7 h. After the holding period, argon gas was introduced to a furnace pressure of 1 kPa, and the temperature was raised to 750 °C for 2 h and then 950 °C for 2 h. After the holding period, the plate was cooled and removed from the furnace. Finally, the prepared TiMn-Ti plate was soaked and cleaned in 0.5 mol / L dilute sulfuric acid until no bubbles were generated, then it was removed, cleaned, and dried to obtain the TiMn-Ti anode plate for electrolytic preparation of MnO2. Testing revealed that the TiMn-Ti anode plate had a tensile strength of 480 MPa, an elongation of 18%, a surface Mn content of 65.1%, and the main phase on the plate surface was TiMn2.

[0052] Example 4

[0053] First, a 1.5mm thick industrial-grade TA1 titanium plate was selected and cut into 40mm × 80mm pieces. The surface of the Ti plate was sandblasted to roughen it, and then washed with water to remove residual dirt. Next, the surface was cleaned with ethanol to remove oil stains, and then washed again with water to remove residue. Then, the treated Ti plate was immersed in a boiling 10% oxalic acid solution for 60 minutes for surface hydrogenation treatment, washed again with water to remove residual acid, and vacuum dried for later use. Then, an organic dispersant was prepared by mixing ethanol and PVB powder at a mass ratio of 8:3 and stirring thoroughly. Electrolytic Mn powder with a particle size of 30μm was selected and mixed with the organic dispersant at a mass ratio of 1:1. The mixture was thoroughly stirred under ultrasonication and then placed in a vacuum chamber for vacuum degassing to form a stable suspension slurry. Next, the gap of the coating device was adjusted to 200 μm, and the obtained slurry was poured onto the surface of the treated Ti plate. A Mn coating layer was evenly coated using a scraper. The coated sample was first allowed to stand and dry for 30 min, and then transferred to a vacuum oven to dry at 80 °C for 1 h. After cooling, the green blank was removed and transferred to a sintering furnace. Under vacuum, it was held at 120 °C for 0.5 h; 350 °C for 1 h; 450 °C for 1 h; 550 °C for 1 h; and then at 600 °C for 0.7 h. After the holding period, argon gas was introduced to bring the furnace pressure to 80 Pa, and the temperature was raised to 800 °C for 1 h and then to 880 °C for 3 h. After the holding period, the plate was cooled and removed from the furnace. Finally, the prepared TiMn-Ti plate was soaked and cleaned with 0.5 mol / L dilute sulfuric acid until no bubbles were generated, and then it was removed, cleaned, and dried to obtain the TiMn-Ti anode plate for electrolytic preparation of MnO2. The above-mentioned TiMn-Ti anode plate was tested and found to have a tensile strength of 410 MPa, an elongation of 24.3%, a surface Mn content of 63.2%, and the main phase on the surface of the plate was TiMn2.

[0054] Example 5

[0055] First, a 1.5mm thick industrial-grade TA1 titanium plate was selected and cut into 40mm × 80mm pieces. The surface of the Ti plate was sandblasted to roughen it, and then washed with water to remove residual dirt. Next, the surface was cleaned with ethanol to remove oil stains, and then washed again with water to remove residue. Then, the treated Ti plate was immersed in a boiling 10% oxalic acid solution for 60 minutes for surface hydrogenation treatment, washed again with water to remove residual acid, and vacuum dried for later use. Then, an organic dispersant was prepared by mixing ethanol and PVB powder at a mass ratio of 8:3 and stirring thoroughly. Electrolytic Mn powder with a particle size of 30μm was selected and mixed with the organic dispersant at a mass ratio of 1:1. The mixture was thoroughly stirred under ultrasonication and then placed in a vacuum chamber for vacuum degassing to form a stable suspension slurry. Next, the gap of the coating device was adjusted to 200 μm, and the obtained slurry was poured onto the surface of the treated Ti plate. A Mn coating layer was evenly coated using a scraper. The coated sample was first allowed to stand and dry for 30 min, and then transferred to a vacuum oven to dry at 80 °C for 1 h. After cooling, the green blank was removed and transferred to a sintering furnace. Under vacuum, it was held at 120 °C for 0.5 h; 350 °C for 1 h; 450 °C for 1 h; 550 °C for 1 h; and then at 600 °C for 0.7 h. After the holding period, argon gas was introduced to a furnace pressure of 80 Pa, and the temperature was raised to 800 °C for 1 h and then to 930 °C for 2 h. After the holding period, the plate was cooled and removed from the furnace. Finally, the prepared TiMn-Ti plate was soaked and cleaned with 0.5 mol / L dilute sulfuric acid until no bubbles were generated, and then it was removed, cleaned, and dried to obtain the TiMn-Ti anode plate for electrolytic preparation of MnO2. The above-mentioned TiMn-Ti anode plate was tested and found to have a tensile strength of 450 MPa, an elongation of 21.3%, a surface Mn content of 66.2%, and the main phase on the surface of the plate was TiMn2.

[0056] Example 6

[0057] First, a 1.5mm thick industrial-grade TA1 titanium plate was selected and cut into 40mm × 80mm pieces. The surface of the Ti plate was sandblasted to roughen it, and then washed with water to remove residual dirt. Next, the surface was cleaned with ethanol to remove oil stains, and then washed again with water to remove residue. Then, the treated Ti plate was immersed in a boiling 10% oxalic acid solution for 60 minutes for surface hydrogenation treatment, washed again with water to remove residual acid, and vacuum dried for later use. Then, an organic dispersant was prepared by mixing ethanol and PVB powder at a mass ratio of 8:3 and stirring thoroughly. Electrolytic Mn powder with a particle size of 30μm was selected and mixed with the organic dispersant at a mass ratio of 1:1. The mixture was thoroughly stirred under ultrasonication and then placed in a vacuum chamber for vacuum degassing to form a stable suspension slurry. Next, the gap of the coating tool was adjusted to 200 μm, and the obtained slurry was poured onto the surface of the treated Ti plate. A Mn coating layer was evenly coated using a scraper. The coated sample was first allowed to stand and dry for 30 min, and then transferred to a vacuum oven to dry at 80 °C for 1 h. After cooling, the green blank was removed and transferred to a sintering furnace. Under vacuum, it was held at 120 °C for 0.5 h; 350 °C for 1 h; 450 °C for 1 h; 550 °C for 1 h; and then at 600 °C for 0.7 h. After the holding period, argon gas was introduced to a furnace pressure of 100 Pa, and the temperature was raised to 800 °C for 1 h and then to 1000 °C for 2 h. After the holding period, the plate was cooled and removed from the furnace. Finally, the prepared TiMn-Ti plate was soaked and cleaned with 0.5 mol / L dilute sulfuric acid until no bubbles were generated, and then it was removed, cleaned, and dried to obtain the TiMn-Ti anode plate for electrolytic preparation of MnO2. Testing revealed that the TiMn-Ti anode plate exhibited a tensile strength of 490 MPa, an elongation of 8%, a surface Mn content of 67.9%, and TiMn2 as the main phase on the plate surface. Under the conditions described in this embodiment, the elongation of the obtained TiMn-Ti anode plate decreased due to the higher calcination temperature.

[0058] Comparative Example 1

[0059] First, a 1.5mm thick industrial-grade TA1 titanium plate was selected and cut into 40mm × 80mm pieces. The surface of the Ti plate was sandblasted to roughen it, and then washed with water to remove residual dirt. Next, the surface was cleaned with ethanol to remove oil stains, and then washed again with water to remove residue. Then, the treated Ti plate was immersed in a boiling 10% oxalic acid solution for 60 minutes for surface hydrogenation treatment, washed again with water to remove residual acid, and vacuum dried for later use. Then, an organic dispersant was prepared by mixing ethanol and PVB powder at a mass ratio of 8:3 and stirring thoroughly. Electrolytic Mn powder with a particle size of 30μm was selected and mixed with the organic dispersant at a mass ratio of 1:1. The mixture was thoroughly stirred under ultrasonication and then placed in a vacuum chamber for vacuum degassing to form a stable suspension slurry. Next, the gap of the coating device was adjusted to 200 μm, and the obtained slurry was poured onto the surface of the treated Ti plate. A Mn coating layer was evenly coated using a scraper. The coated sample was first allowed to stand and dry for 30 min, and then transferred to a vacuum oven to dry at 80 °C for 1 h. After cooling, the green blank was removed and transferred to a sintering furnace. Under vacuum, it was held at 120 °C for 0.5 h; 350 °C for 1 h; 450 °C for 1 h; 550 °C for 1 h; and then at 600 °C for 0.7 h. After the holding period, argon gas was introduced to a furnace pressure of 100 Pa, and then the furnace was held at 900 °C for 3 h. After the holding period, the plate was cooled and removed from the furnace. Finally, the prepared TiMn-Ti plate was soaked and cleaned with 0.5 mol / L dilute sulfuric acid until no bubbles were generated, and then it was removed, cleaned, and dried to obtain the TiMn-Ti anode plate for electrolytic preparation of MnO2. Testing revealed that the TiMn-Ti anode plate exhibited a tensile strength of 430 MPa, an elongation of 20.1%, and a surface Mn content of 25.2%. The main phases on the anode plate surface were βTi(Mn) solid solution and TiMn2. The TiMn-Ti anode plate prepared under these comparative conditions had a low manganese content, and its surface phases primarily consisted of βTi(Mn) solid solution and TiMn2. Furthermore, due to the direct increase in reaction diffusion temperature to high temperatures, the Mn powder layer shrank more than the Ti plate, resulting in a Mn-rich layer flaking off the surface of the TiMn-Ti anode plate after cooling and removal from the furnace.

[0060] Comparative Example 2

[0061] First, a 1.5mm thick industrial-grade TA1 titanium plate was selected and cut into 40mm × 80mm pieces. The surface of the Ti plate was sandblasted to roughen it, and then washed with water to remove residual dirt. Next, the surface was cleaned with ethanol to remove oil stains, and then washed again with water to remove residue. Then, the treated Ti plate was immersed in a boiling 10% oxalic acid solution for 60 minutes for surface hydrogenation treatment, washed again with water to remove residual acid, and vacuum dried for later use. Then, an organic dispersant was prepared by mixing ethanol and PVB powder at a mass ratio of 8:3 and stirring thoroughly. Electrolytic Mn powder with a particle size of 30μm was selected and mixed with the organic dispersant at a mass ratio of 1:1. The mixture was thoroughly stirred under ultrasonication and then placed in a vacuum chamber for vacuum degassing to form a stable suspension slurry. Next, the gap of the coating device was adjusted to 200 μm, and the obtained slurry was poured onto the surface of the treated Ti plate. A Mn coating layer was evenly coated using a scraper. The coated sample was first allowed to stand and dry for 30 min, and then transferred to a vacuum oven to dry at 80 °C for 1 h. After cooling, the green blank was removed and transferred to a sintering furnace. Under vacuum, it was held at 120 °C for 0.5 h; 350 °C for 1 h; 450 °C for 1 h; 550 °C for 1 h; then at 600 °C for 0.7 h; 800 °C for 1 h; and 900 °C for 2 h. After the holding time was completed, it was cooled and removed from the furnace. Finally, the prepared TiMn-Ti plate was soaked and cleaned with 0.5 mol / L dilute sulfuric acid until no bubbles were generated, then removed, cleaned, and dried to obtain the TiMn-Ti anode plate for electrolytic preparation of MnO2. Testing revealed that the TiMn-Ti anode plate exhibited a tensile strength of 401 MPa, an elongation of 23.8%, and a surface Mn content of 18.3%. The main phase on the anode plate surface was βTi(Mn) solid solution, and a thick Mn-rich metal layer was deposited on the inner wall of the sintering furnace. The primary reason for this result was that the segmented manganese infiltration process was consistently carried out under high vacuum conditions without proper pressure control.

Claims

1. A method for preparing a TiMn alloy anode material, characterized in that: A TiMn green blank is obtained by coating the surface of a titanium substrate with a manganese-containing paste. The TiMn green blank is then subjected to low-temperature degreasing and dehydrogenation under vacuum conditions not exceeding 600°C. Then, an inert gas is introduced to a pressure of 1 Pa to 25 kPa, and the temperature is raised to 750 to 800°C and held for 1 to 2 hours for medium-temperature manganese infiltration. The temperature is then raised to 850 to 950°C and held for 2 to 4 hours for high-temperature manganese infiltration to obtain a TiMn-Ti plate. The TiMn-Ti plate is then washed after being soaked in an acid solution to obtain the final product.

2. The method for preparing a TiMn alloy anode material according to claim 1, characterized in that: The titanium substrate undergoes a pretreatment process including sandblasting and oxalic acid surface hydrogenation.

3. The method for preparing a TiMn alloy anode material according to claim 2, characterized in that: The oxalic acid concentration is 5% to 15%.

4. The method for preparing a TiMn alloy anode material according to claim 1, characterized in that: The manganese-containing slurry includes manganese powder and an organic dispersant; The organic dispersant is a non-water-soluble organic dispersant; The mass ratio of manganese powder to organic dispersant is 0.2~2:

1.

5. A method for preparing a TiMn alloy anode material according to claim 1 or 4, characterized in that: The coating thickness is 100~300µm.

6. The method for preparing a TiMn alloy anode material according to claim 1, characterized in that: The low-temperature degreasing and dehydrogenation process is as follows: at 10 -4 ~10 -2 Under vacuum pressure of Pa, first keep at 100~120℃ for 0.5~1h, then keep at 350~550℃ for 2~4h, and then keep at 550~600℃ for 1~2h.

7. A TiMn alloy anode material, characterized in that: Prepared by the method described in any one of claims 1 to 6.

8. The application of the TiMn alloy anode material according to claim 7, characterized in that: MnO2 was prepared by anodic electrolysis.

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