Titanium metal component and method for producing same, electrochemical device

Abstract

The present application relates to a kind of titanium metal parts and its preparation method, electrochemical equipment, wherein the titanium metal part includes titanium base material and the coating arranged on the surface of the titanium base material, the coating includes first phase and second phase, the first phase is R5Ti3F 14 And / or TiO x , R is selected from alkali metal, x<2, the second phase is sp 3 Hybrid carbon phase.The coating in the titanium metal part of the present application can consider low contact resistance, corrosion resistance and high potential stability and other indicators, not only can be formed in situ using wet low-temperature process, low cost, and has regeneration repair ability.

Description

Technical Field

[0001] This invention relates to the fields of surface engineering and electrochemical protection technology, and in particular to titanium metal components and their preparation methods, as well as electrochemical equipment. Background Technology

[0002] Titanium and titanium alloys possess high corrosion resistance and mechanical strength, making them promising candidates for applications such as fuel cell bipolar plates and electrolytic cell plates. Currently, the mainstream approaches for preparing conductive and corrosion-resistant coatings on titanium substrates primarily involve vacuum deposition or high-energy surface modification, including the formation of TiN, TiC, amorphous carbon (aC), or their composite multilayer films on the titanium substrate surface through magnetron sputtering, ion plating, and composite diffusion layers.

[0003] For example, CN111342073A discloses a titanium metal bipolar plate and its fabrication method, which constructs a carbonitriding layer mainly composed of TiC and TiN on the surface of the titanium plate; CN114277344A discloses a titanium bipolar plate for fuel cells and its preparation method, which constructs a multilayer film system on the surface of a titanium substrate, including a Ti layer, an aC:H:Ti transition layer, and a graphite-like layer; CN117254055A and EP4088332B1 also adopt a layered film system design with a Ti intermediate layer, a TiN interface layer, and an aC surface layer. Although such technologies can improve conductivity and corrosion resistance, they usually have problems such as high equipment investment and long process chains, making it difficult to stably achieve low contact resistance, corrosion resistance, and high potential stability under low-cost process conditions, and the coating cannot be regenerated and repaired after damage. Summary of the Invention

[0004] Therefore, it is necessary to provide a titanium metal component and its preparation method and electrochemical device to address the above problems. The coating in the titanium metal component can take into account indicators such as low contact resistance, corrosion resistance and high potential stability. It can not only be formed in situ by wet low temperature process, which is low cost, but also has regeneration and repair capabilities.

[0005] A titanium metal component includes a titanium substrate and a coating disposed on the surface of the titanium substrate. The coating includes a first phase and a second phase, wherein the first phase is R5Ti3F. 14 and / or TiO x Where R is selected from alkali metals, x < 2, and the second phase is sp. 3 Hybridized carbon phase.

[0006] In one embodiment, the coating is formed by stacking multiple sheet-like units.

[0007] In one embodiment, the sheet-like unit has a lateral dimension of 0.1 μm to 1 μm, a longitudinal dimension of 0.5 μm to 2.0 μm, and a thickness of 0.05 μm to 0.1 μm.

[0008] In one embodiment, R is selected from at least one of Na, K, or Li;

[0009] And / or, when the first phase is R5Ti3F 14 At that time, the R5Ti3F 14 The proportion in the coating is 50% to 95%;

[0010] And / or, the titanium substrate is selected from titanium metal substrate or titanium alloy substrate;

[0011] And / or, the thickness of the coating is 50nm~200nm;

[0012] And / or, there is no transition layer between the titanium substrate and the coating.

[0013] A method for preparing the titanium metal component involves treating a titanium workpiece with a treatment solution under heating conditions to obtain the titanium metal component, or first treating the titanium workpiece with a treatment solution under heating conditions and then performing anodizing treatment to obtain the titanium metal component.

[0014] Wherein, the titanium workpiece is a titanium substrate or a titanium metal part with a failed coating, the treatment liquid includes an aqueous solution of alkali metal fluoride and acid, and when the acid is an inorganic acid, the treatment liquid also includes a complexing agent.

[0015] In one embodiment, the alkali metal fluoride is selected from at least one of lithium fluoride, potassium fluoride, and sodium fluoride;

[0016] And / or, the concentration of alkali metal fluorides in the treatment solution is 0.05 mol / L to 0.4 mol / L.

[0017] In one embodiment, the acid is selected from at least one of oxalic acid, citric acid, malic acid, tartaric acid, malonic acid, succinic acid, sulfuric acid, and hydrochloric acid;

[0018] And / or, the concentration of acid in the treatment solution is 0.05 mol / L to 0.4 mol / L.

[0019] In one embodiment, the complexing agent is selected from acetylacetone;

[0020] And / or, the concentration of the complexing agent in the treatment solution is 0.01 mol / L to 0.03 mol / L.

[0021] In one embodiment, the heating condition is at a temperature of 70°C to 100°C;

[0022] And / or, the treatment time for titanium workpieces using the treatment solution is 1 min to 30 min;

[0023] And / or, prior to the step of treating the titanium substrate with the treatment solution, the titanium substrate is further pretreated to remove the surface oxide layer of the titanium substrate;

[0024] And / or, after the step of treating the titanium workpiece with the treatment solution, it also includes cleaning and drying.

[0025] An electrochemical device comprising the aforementioned titanium metal component.

[0026] The titanium metal component provided by this invention has a TiO2 coating. x It has excellent electrical conductivity, while R5Ti3F 14 In an anodic oxidation environment, it can also be converted into TiO2. x Instead of insulating titanium dioxide (TiO2), it maintains a low interfacial contact resistance even under electrochemical conditions; simultaneously, sp 3 Hybrid carbon phases have good chemical inertness and electrical conductivity, which can further reduce the overall contact resistance of the coating and enhance its corrosion resistance, enabling the coating to achieve a balance of low contact resistance, corrosion resistance and high potential stability.

[0027] Furthermore, the coating of this invention can be formed in situ on the surface of a titanium substrate using a wet low-temperature process, eliminating the need for expensive equipment such as vacuum coating. The process is simple, low-cost, and easily scalable. Moreover, when the coating experiences increased contact resistance due to surface passivation after prolonged use, the failed titanium metal parts can be re-treated with the processing solution to regenerate a new coating with the same properties in situ on the original surface. This endows the titanium metal parts with excellent replating and repair capabilities, significantly extending their service life and reducing maintenance costs. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a surface morphology diagram of the coating obtained in Example 1 of the present invention;

[0030] Figure 2 This is a cross-sectional view of the coating obtained in Example 1 of the present invention;

[0031] Figure 3 This is the XPS full spectrum of the coating obtained in Example 1 of the present invention;

[0032] Figure 4 The image shows the GI-XRD pattern of the coating obtained in Example 1 of this invention.

[0033] Figure 5 This is the XPS full spectrum of the coating after anodizing obtained in Example 1 of the present invention. Detailed Implementation

[0034] To facilitate understanding of the present invention, it will be described in more detail below. However, it should be understood that the present invention can be implemented in many different forms and is not limited to the embodiments or examples described herein. Rather, these embodiments or examples are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments or examples only and is not intended to limit the invention. The optional scope of the term "and / or" as used herein includes any one of two or more of the related listed items, as well as any and all combinations of the related listed items, including any two related listed items, any more related listed items, or a combination of all related listed items.

[0036] In this invention, numerical ranges are involved. Unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe features or characteristics, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are included.

[0037] The titanium metal component provided by the present invention includes a titanium substrate and a coating disposed on the surface of the titanium substrate. The coating includes a first phase and a second phase, wherein the first phase is R5Ti3F. 14 and / or TiO x Where R is selected from alkali metals, x < 2, and the second phase is sp. 3 Hybridized carbon phase.

[0038] It is understood that the coating may include R5Ti3F 14 and sp 3 Hybrid carbon phases may also include TiO2. x and sp 3 Hybrid carbon phases may also include R5Ti3F 14 TiOx and sp 3 Hybridized carbon phase.

[0039] Due to TiO x It has excellent electrical conductivity, while R5Ti3F 14 In an anodic oxidation environment, it can also be converted into TiO2. x Instead of insulating titanium dioxide (TiO2), the coating maintains a low interfacial contact resistance under electrochemical conditions; simultaneously, sp 3 Hybrid carbon phases have good chemical inertness and electrical conductivity, which can further reduce the overall contact resistance of the coating and enhance its corrosion resistance, thus enabling the coating to achieve a balance of low contact resistance, corrosion resistance and high potential stability.

[0040] Optionally, the coating of the present invention is formed by stacking multiple sheet-like units. This structure can endow the coating with abundant micro gaps and pore channels, increase the specific surface area of ​​the coating, and help reduce the interfacial contact resistance. At the same time, the structure itself has a certain stress release capability, which can avoid the cracking and peeling of dense coatings, enhance the bonding stability between the coating and the titanium substrate, and thus maintain good corrosion resistance and electrical conductivity during long-term use.

[0041] The sheet-like unit preferably has a lateral dimension of 0.1μm to 1μm, a longitudinal dimension of 0.5μm to 2.0μm, and a thickness of 0.05μm to 0.1μm. This micro-nano scale range can ensure sufficient specific surface area to reduce contact resistance, while also taking into account the structural integrity and crack resistance of the coating.

[0042] Optionally, the thickness of the coating is 50nm~200nm. This thickness range ensures complete coverage and corrosion resistance while avoiding problems such as increased internal stress, cracking, and increased contact resistance caused by excessive thickness. This allows the coating to balance low contact resistance and excellent corrosion resistance, meeting the requirements for long-term use under harsh working conditions.

[0043] Optionally, R5Ti3F 14 R is selected from at least one of Na, K, or Li. These alkali metal ions can coordinate with titanium and fluorine ions during coating formation, promoting the formation of R5Ti3F. 14 Stable formation. R is further preferably Na, because Na... + Its moderate ionic radius and strong coordination ability with Ti-F complexes are conducive to the formation of well-crystallized and dense R5Ti3F complexes. 14 This results in lower interfacial contact resistance and better corrosion resistance; at the same time, sodium salts are widely available and inexpensive, making them more suitable for large-scale industrial applications.

[0044] To further balance the electrical conductivity and corrosion resistance of the coating, preferably, when the coating includes R5Ti3F... 14 and sp 3 When the carbon phase is hybridized, the R5Ti3F 14 The molar proportion in the coating is 50% to 95%. Within this preferred range, the coating has sufficient conductive phase to reduce interfacial contact resistance, while retaining an appropriate amount of sp. 3 Hybridized carbon phases enhance corrosion resistance and structural stability, enabling the coating to achieve superior overall performance. TiO₂... x From the R5Ti3F 14 The transformation is obtained, therefore, when the coating contains TiO2. x At that time, the ratios among the three can be converted according to the degree of conversion.

[0045] It is understood that the titanium substrate described in this invention is selected from titanium metal substrates or titanium alloy substrates.

[0046] The present invention also provides a method for preparing the titanium metal component, wherein the processing solution used in the preparation method comprises an aqueous solution of an alkali metal fluoride and an acid, wherein the acid may be selected from at least one of organic acids and / or inorganic acids. Since organic acids themselves have the ability to complex titanium ions, the addition of a complexing agent is optional when the acid contains an organic acid, while when the acid is an inorganic acid, the processing solution needs to contain a complexing agent. Optionally, the processing solution is an aqueous solution comprising an alkali metal fluoride and an organic acid, or the processing solution is an aqueous solution comprising an alkali metal fluoride, an inorganic acid, and a complex.

[0047] The alkali metal fluoride is selected from at least one of lithium fluoride, potassium fluoride, and sodium fluoride, more preferably sodium fluoride, and the concentration of the alkali metal fluoride in the treatment solution is 0.05 mol / L to 0.4 mol / L; the acid is selected from at least one of oxalic acid, citric acid, malic acid, tartaric acid, malonic acid, succinic acid, sulfuric acid, and hydrochloric acid, and the concentration of the acid in the treatment solution is 0.05 mol / L to 0.4 mol / L; the complexing agent is selected from acetylacetone, and the concentration of the complexing agent in the treatment solution is 0.01 mol / L to 0.03 mol / L.

[0048] Specifically, the preparation method is as follows: a treatment solution is used to treat the titanium workpiece under heating conditions, so that titanium ions in the titanium workpiece react in situ with alkali metal ions and fluoride ions in the treatment solution to generate R5Ti3F. 14 Simultaneously, the organic acids and complexing agents are reduced by the electrons lost in the titanium oxidation reaction to generate sp. 3 In the case of a hybrid carbon phase, the resulting titanium metal component has a coating comprising R5Ti3F. 14 and sp 3 Hybridized carbon phase.

[0049] Of course, after treating the titanium workpiece with a treatment solution under heating conditions, anodizing can also be performed to remove the R5Ti3F in the coating. 14 Converted to TiO x Specifically, the voltage, time, and other conditions of anodizing can be controlled to make R5Ti3F 14 Partially or completely converted to TiO x At this point, the titanium metal component obtained has a coating including R5Ti3F. 14 TiO x and sp 3 Hybridized carbon phase, or only TiO2 x and sp 3 Hybridized carbon phase.

[0050] In the preparation method of the present invention, the titanium workpiece is a titanium substrate with no coating on its surface. Before the step of treating the titanium substrate with the treatment liquid, the titanium substrate is further pretreated to remove the surface oxide layer of the titanium substrate. The pretreatment method can be electrolytic pickling, and the electrolytic pickling time is preferably 0.5 min to 10 min, more preferably 1 min to 5 min, and more preferably 3 min.

[0051] During long-term use, the titanium metal component of this invention may experience passivation in the coating due to the formation of loose TiO2 particles, leading to increased contact resistance and ultimately causing the titanium metal component to fail. Therefore, in the preparation method of this invention, the titanium workpiece can also be a titanium metal component with a failed coating. In this case, during the heat treatment of the failed titanium metal component using a treatment solution, the acid in the treatment solution can corrode and remove the TiO2 particles and TiO2 residues from the coating. x Simultaneously, the alkali metal fluorides and acids (and complexing agents) in the treatment solution can re-react with the exposed titanium substrate, regenerating in situ R5Ti3F. 14 and sp 3 A hybrid carbon phase coating is used to achieve coating repair and regeneration.

[0052] Therefore, the coating of the present invention can be formed in situ on the surface of a titanium substrate using a wet low-temperature process, eliminating the need for expensive equipment such as vacuum coating. The process is simple, low-cost, and easy to scale up. Furthermore, when the coating experiences increased contact resistance due to surface passivation after long-term use, the failed titanium metal parts can be re-treated with the processing solution to regenerate a new coating with the same properties in situ on the original surface. This endows the titanium metal parts with excellent replating and repair capabilities, significantly extending their service life and reducing maintenance costs.

[0053] To achieve excellent electrical conductivity while ensuring efficient coating formation, this invention controls the heating temperature to 70℃~100℃ and the processing time to 1min~30min. This temperature range ensures sufficient kinetic driving force for the reaction, which is beneficial to R5Ti3F. 14 and sp 3 Sufficient formation and good crystallization of the hybrid carbon phase; this time range ensures both complete coating coverage and appropriate thickness, while also taking into account production efficiency, enabling the coating to achieve low interfacial contact resistance and good uniformity.

[0054] It is understood that after the step of treating the titanium workpiece with the treatment liquid, the present invention may also include a cleaning and drying step.

[0055] It should be noted that, since the present invention uses a wet low-temperature process and does not involve high-temperature heat treatment, there is no element diffusion phenomenon during the coating formation process. The titanium substrate and the coating are directly chemically bonded interfaces, and there is no intermediate transition layer. That is, there is no transition layer between the titanium substrate and the coating.

[0056] The present invention also provides an electrochemical device including the aforementioned titanium metal component. It is understood that the electrochemical device can be a fuel cell bipolar plate, an electrolyzer plate, etc. For example, when the electrochemical device is a fuel cell bipolar plate, the titanium metal component can be used as the metal bipolar plate.

[0057] The technical solution of the present invention will be further described below through specific embodiments. However, those skilled in the art will understand that the following embodiments are only for illustrating the present invention and should not be regarded as limiting the scope of the present invention. Unless otherwise specified, specific conditions in the embodiments are performed under conventional conditions or conditions recommended by the manufacturer. Reagents or instruments used without specified manufacturers are all commercially available conventional products.

[0058] Example 1

[0059] TA1 titanium plate was used as the titanium substrate, and degreasing and cleaning were performed. The titanium substrate underwent electrolytic acid pickling pretreatment for 3 minutes. Subsequently, the pretreated titanium substrate was immersed in an aqueous solution containing 0.2 mol / L sodium fluoride and 0.2 mol / L oxalic acid, and reacted at 95°C for 5 minutes. After removal, the sample was washed with deionized water and dried to obtain a black coating.

[0060] The sample was characterized by scanning electron microscopy (SEM), and the results are as follows: Figure 1As shown, the surface exhibits a rough, multi-level structure dominated by lamellar units. These lamellar units are randomly oriented and overlap each other, with clear edges and sharp corners. There are numerous gaps, microcracks, and local cavities between the lamellar units, forming a certain amount of open pore channels. The lamellar units have a transverse dimension of 0.1 μm to 1 μm, a longitudinal dimension of 0.5 μm to 2.0 μm, and a thickness of 0.05 μm to 0.1 μm.

[0061] The cross-section of the coating was characterized by FIB-SEM, which was used to characterize the protective layer previously prepared on the coating surface. The results are as follows: Figure 2 As shown, the coating thickness ranges from 50 nm to 100 nm.

[0062] XPS characterization results are as follows Figure 3 As shown, from Figure 3 It can be seen that the coating contains only Na, Ti, F, C and O elements.

[0063] The GI-XRD characterization results with an X-ray incident angle of 3° are as follows: Figure 4 As shown, from Figure 4 It can be seen that Na5Ti3F was formed on the surface of the titanium substrate. 14 The phase of (PDF 00-027-0816) has a characteristic peak at 29.48°, and also contains sp. 3 The hybrid carbon phase (PDF 01-080-0017) has a characteristic peak at 44.53°. Further analysis revealed that Na₅Ti₃F₂ in the coating... 14 The molar ratio is 93%.

[0064] The surface contact resistance of the prepared sample was measured to be 4.65 mΩ·cm. 2 The samples were then subjected to surface contact resistance tests under different anodizing conditions to simulate different application scenarios. The results are shown in Table 1.

[0065] Table 1: Surface contact resistance of the coating described in Example 1 after testing under different anodizing conditions

[0066]

[0067] As shown in Table 1, after anodizing under different potential conditions, the surface contact resistance of the coating remained stable at 10 mΩ·cm. 2 Around 20 mΩ·cm 2 The application requirements demonstrate that the coating of this invention still exhibits excellent stability under high voltage and strong oxidation conditions.

[0068] Furthermore, XPS characterization of the anodized surface yielded the following results: Figure 5 As shown, by Figure 5It can be seen that the surface mainly contains Ti atoms bonded to O atoms. 3+ and Ti 4+ Composite TiO x The chemical structural characteristics of Na5Ti3F 14 It is converted into TiO during the anodizing process. x .

[0069] Example 2

[0070] The only difference between Example 2 and Example 1 is that the reaction temperature was changed to 65℃, 75℃, and 85℃. The surface contact resistance was measured after preparation, and the results are shown in Table 2.

[0071] Table 2

[0072]

[0073] As shown in Table 2, within the tested reaction temperature range, the surface contact resistance of the coating is consistently below 20 mΩ·cm. 2 The application requirements indicate that the process of this invention has stable conductivity over a wide temperature window.

[0074] Example 3

[0075] The only difference between Example 3 and Example 1 is that the reaction time was changed to 1 min, 2 min, 3 min, and 4 min. The surface contact resistance was measured after preparation, and the results are shown in Table 3.

[0076] Table 3

[0077]

[0078] As shown in Table 3, within the tested reaction time range, the surface contact resistance of the coating is consistently below 20 mΩ·cm. 2 The application requirements indicate that the process of this invention has a wide tolerance window for reaction time.

[0079] Example 4

[0080] The only difference between Example 4 and Example 1 is the change in the ratio of oxalic acid to sodium fluoride in the reaction solution. The surface contact resistance was measured after preparation, and the results are shown in Table 4.

[0081] Table 4

[0082]

[0083] As shown in Table 4, within the tested ratio range of oxalic acid to sodium fluoride, the surface contact resistance of the coating is consistently below 20 mΩ·cm. 2 The application requirements indicate that the process of this invention has a wide tolerance window for the ratio of the treatment liquid.

[0084] Example 5

[0085] The only difference between Example 5 and Example 1 is that citric acid, malic acid, tartaric acid, malonic acid, and succinic acid were selected as the acids for coating preparation, respectively. The surface contact resistance was measured after preparation, and the results are shown in Table 5.

[0086] Table 5

[0087]

[0088] Example 6

[0089] The only difference between Example 6 and Example 1 is that sulfuric acid and hydrochloric acid, respectively, were used as inorganic acids for coating preparation, and acetylacetone was added as a complexing agent to increase solution stability. The surface contact resistance was measured after preparation, and the results are shown in Table 6.

[0090] Table 6

[0091]

[0092] As shown in Tables 5 and 6, the method of the present invention has wide applicability to both organic and inorganic acids.

[0093] Example 7

[0094] The only difference between Example 7 and Example 1 is that LiF and KF were used as fluorinated salts for coating preparation, respectively. The surface contact resistance was measured after preparation, and the results are shown in Table 7.

[0095] Table 7

[0096]

[0097] As shown in Table 7, the surface contact resistance of the samples is at a similar level under different alkali metal fluoride salt conditions, indicating that the type of alkali metal has a relatively small impact on the conductivity of the coating, and the present invention has a wide applicability to the selected alkali metal ions.

[0098] Example 8

[0099] The anodized sample was recoated according to the method in Example 1. The surface contact resistance of the sample is shown in Table 8, and it can be restored to the initial low contact resistance range.

[0100] Table 8

[0101]

[0102] Comparative Example 1

[0103] A solution of 0.2M sodium hexafluorotitanate, 0.2M sodium chloride, and 0.2M boric acid was prepared. After heating the solution to 60°C, the titanium substrate was immersed in the solution for 4 hours. Finally, the sample was dried and tested. The results showed that the coating was composed of Na₅Ti₃F₂. 14 It is composed of TiO2, and the contact resistance test results are shown in Table 9.

[0104] Table 9

[0105]

[0106] As shown in Table 9, the surface resistivity of the sample prepared in Comparative Example 1 significantly exceeds the 20 mΩ / cm limit allowed by the electrochemical electrode coating. 2 Contact resistance.

[0107] In the above embodiments and comparative examples, the test methods for contact resistance and corrosion electrochemistry are as follows:

[0108] Surface contact resistance test: The contact resistance was determined using the method shown in GB / T 20042.6-2011. The carbon paper used to simulate the gas diffusion layer was hydrophobic carbon paper (TGP-H-060) manufactured by Toray Industries. During the test, firstly, according to the national standard GB / T20042.7-2014, a single sheet of carbon paper was used to calibrate the resistance of the actual test system, including the contact resistance between the carbon paper and the gold electrode surface and the carbon paper's bulk resistance, to obtain R1. Then, two sheets of carbon paper were sandwiched between the test sample, and the same contact resistance test was performed to obtain R2. Since the bulk resistance of the test sample is negligible, the contact resistance of the sample can be calculated using R=(R2-R1) / 2.

[0109] Coating stability test: Before testing, the sample was processed into a square with a side length of 5cm and installed on the working electrode of the electrochemical test, with an effective test area of ​​25cm². 2 A traditional three-electrode system, comprising a working electrode, an Ag / AgCl reference electrode, and a platinum counter electrode, was connected to an electrochemical workstation (CHI600E, CH Instruments Ins) via wires. The corrosive environment was set at 80°C, pH=3, and containing 0.1 ppm F. - A sulfuric acid solution was used. A potentiostatic scan was performed at a specific voltage and time (e.g., 24 h at 0.84 V vs. SHE as previously mentioned) to simulate the corrosive environment of anodizing under actual conditions. This potentiostatic scan was performed under oxygen-bearing conditions at a flow rate of 20 mL / min. After anodizing, the contact resistance of the sample was measured. Typically, a well-stability coating can maintain a surface contact resistance of 20 mΩ / cm. 2 the following.

[0110] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0111] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A titanium metal component, characterized in that, The titanium metal component includes a titanium substrate and a single-layer coating disposed on the surface of the titanium substrate. The coating is formed by stacking multiple sheet-like units and includes a first phase and a second phase, wherein the first phase is R5Ti3F. 14 and / or TiO x Where R is selected from alkali metals, x < 2, and the second phase is sp. 3 Hybridized carbon phase.

2. The titanium metal component according to claim 1, characterized in that, The sheet-like unit has a lateral dimension of 0.1μm to 1μm, a longitudinal dimension of 0.5μm to 2.0μm, and a thickness of 0.05μm to 0.1μm.

3. The titanium metal component according to any one of claims 1 to 2, characterized in that, R is selected from at least one of Na, K, or Li; And / or, when the first phase is R5Ti3F 14 At that time, the R5Ti3F 14 The molar proportion in the coating is 50%~95%; And / or, the titanium substrate is selected from titanium metal substrate or titanium alloy substrate; And / or, the thickness of the coating is 50nm~200nm; And / or, there is no transition layer between the titanium substrate and the coating.

4. A method for preparing a titanium metal component as described in any one of claims 1 to 3, characterized in that, Titanium workpieces are treated with a treatment solution under heating conditions to obtain titanium metal parts; or, titanium workpieces are first treated with a treatment solution under heating conditions, and then anodized to obtain titanium metal parts. Wherein, the titanium workpiece is a titanium substrate or a titanium metal part with a failed coating, the treatment liquid includes an aqueous solution of alkali metal fluoride and acid, and when the acid is an inorganic acid, the treatment liquid also includes a complexing agent.

5. The method for preparing titanium metal parts according to claim 4, characterized in that, The alkali metal fluoride is selected from at least one of lithium fluoride, potassium fluoride, and sodium fluoride; And / or, the concentration of alkali metal fluorides in the treatment solution is 0.05 mol / L to 0.4 mol / L.

6. The method for preparing titanium metal components according to claim 4, characterized in that, The acid is selected from at least one of oxalic acid, citric acid, malic acid, tartaric acid, malonic acid, succinic acid, sulfuric acid, and hydrochloric acid; And / or, the concentration of acid in the treatment solution is 0.05 mol / L to 0.4 mol / L.

7. The method for preparing titanium metal parts according to claim 4, characterized in that, The complexing agent is selected from acetylacetone; And / or, the concentration of the complexing agent in the treatment solution is 0.01 mol / L to 0.03 mol / L.

8. The method for preparing titanium metal parts according to claim 4, characterized in that, The heating conditions are at a temperature of 70℃~100℃; And / or, the treatment time for titanium workpieces using the treatment solution is 1 min to 30 min; And / or, prior to the step of treating the titanium substrate with the treatment solution, the titanium substrate is further pretreated to remove the surface oxide layer of the titanium substrate; And / or, after the step of treating the titanium workpiece with the treatment solution, it also includes cleaning and drying.

9. An electrochemical device, characterized in that, Includes titanium metal components as described in any one of claims 1 to 3.

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