A MXene modified friction-responsive anti-corrosion coating suitable for alcohol-based fuel ships and a preparation method thereof

Abstract

This invention discloses an MXene-modified tribologically responsive anti-corrosion coating suitable for alcohol-fueled ships and its preparation method. The coating uses MXene nanosheets as a substrate, with a metallic or non-metallic second phase, selected from Pd, Pt, Ni, and Ag, loaded onto its surface as a catalyst. The coating is fixed to the metal substrate surface of the alcohol-fueled ship using an adhesive. Utilizing the catalytic effect of the loaded second phase, during the friction generated during ship operation, it catalyzes the reaction of alcohols in the frictional environment, generating products with both lubricating and protective functions. Simultaneously, leveraging the high conductivity, high specific surface area, and layered structure of the MXene nanosheets, the coating synergistically achieves both friction reduction and corrosion resistance. This invention features a simple preparation process and strong tribological responsiveness, effectively solving the severe corrosion and wear problems of alcohol-fueled ships under the combined action of alcohol immersion and friction, extending the service life of ship components. It is suitable for surface protection of metal components such as the hull, engine, and pipelines of various alcohol-fueled ships.

Description

Technical Field

[0001] This invention belongs to the field of marine anti-corrosion coating technology, specifically relating to a functional coating for the critical friction pair surfaces of alcohol-based fuel (such as methanol, ethanol, etc.) marine engines and its preparation method. This coating possesses both excellent friction-reducing and wear-resistant properties and active corrosion resistance. Background Technology

[0002] As the global shipping industry transitions to a green and low-carbon model, alcohol-based fuels (such as methanol and ethanol) are increasingly being used in the marine sector as a clean alternative fuel. Alcohol-based fuels produce clean combustion products and low sulfur oxide emissions, meeting the increasingly stringent emission regulations of the International Maritime Organization (IMO). Therefore, ships fueled by methanol and ethanol are becoming a new direction for industry development.

[0003] However, alcohol-based fuel ships face severe material failure challenges during actual operation. First, alcohols are polar and hygroscopic, easily leading to electrochemical corrosion of the metal matrix, especially on critical metal components such as the hull, engine block, and fuel lines. Second, alcohol fuels have poorer lubrication properties than traditional fuels. In friction pairs such as engine piston rings and cylinder liners, and fuel injection systems, insufficient lubrication exacerbates friction and wear, significantly shortening component lifespan. More critically, corrosion and friction / wear often occur simultaneously and mutually reinforce each other—corrosion products intensify friction and wear, while wear damages the surface protective layer, accelerating the corrosion process, forming a coupled "friction-corrosion" damage effect that severely restricts the reliability and durability of alcohol-based fuel ships.

[0004] To address the aforementioned problems, while traditional protective coatings can provide a physical barrier to some extent, isolating corrosive media and possessing certain wear resistance, their function is passive and static. Under long-term friction, once the coating experiences localized damage, the corrosive media will rapidly propagate along the defect, leading to coating peeling, substrate corrosion, and rapid failure of the protective function. Existing technologies, such as Chinese patent application CN117070090A, disclose an MXene-based anti-corrosion coating system. This system incorporates MXene as a filler into a water-based inorganic zinc-rich primer, utilizing MXene's chemical stability, weather resistance, and lamellar barrier effect to improve the coating's static anti-corrosion performance. Chinese patent application CN119552530A discloses an MXene / GQDs nano-hybrid filler, which improves the dispersion of MXene in the coating through silane coupling agent modification, inhibiting its oxidation and thus enhancing physical barrier capabilities. However, the anti-corrosion mechanisms of these technologies are still limited to physical barrier effects and cannot actively respond or dynamically repair under friction conditions, making it difficult to cope with the complex service environment of "friction-corrosion" coupling.

[0005] MXene materials possess high conductivity, excellent mechanical strength, and a layered shielding effect, effectively extending the diffusion path of corrosive media, and have attracted widespread attention in the field of corrosion protection in recent years. However, pure MXene struggles to actively regulate the friction environment during friction, particularly when facing the challenges of corrosion and lubrication from alcohol-based media, lacking an effective response mechanism. How to leverage the structural advantages of MXene to endow coatings with the ability to actively respond to the friction process and improve the chemical environment of the friction interface in situ, thereby achieving intelligent protection that simultaneously reduces friction and resists corrosion, is a pressing problem in the current technological field.

[0006] Therefore, developing a novel intelligent coating that can actively respond to the friction process, utilize alcohol media as reactants, and generate lubricating and protective products in situ at the friction interface is of great significance for ensuring the long-term stable operation of alcohol-based fuel ship propulsion systems. Summary of the Invention

[0007] The purpose of this invention is to provide an MXene-modified friction-responsive anti-corrosion coating and its preparation method suitable for alcohol-fueled ships, in order to solve the problems of severe corrosion and wear of metal parts of alcohol-fueled ships under the action of alcohol medium immersion and friction coupling, and the passive and difficult-to-active response of traditional protective coatings.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: An MXene-modified tribologically responsive anti-corrosion coating suitable for alcohol-fueled ships, the coating being applied to a metal substrate surface and comprising: MXene nanosheets; and a second-phase catalyst supported on the surface of the MXene nanosheets; wherein the second-phase catalyst is capable of catalyzing the reaction of alcohols to generate lubricating and / or protective products.

[0009] Furthermore, the second phase catalyst is one or a mixture of two of the following: a metal catalyst and a non-metal catalyst; the metal catalyst is one or more of Pd, Pt, Ni, and Ag; and the non-metal catalyst is one or two of B and N.

[0010] Furthermore, the MXene nanosheets are Ti3C2T. x One or more of Mo2C and Ti2C, with a thickness of 1~10nm and a flake diameter of 0.5~5μm; the Ti3C2T x The end groups on the surface are one or more of -O, -OH, and -F.

[0011] Furthermore, the loading of the second phase catalyst is 1 to 10 wt% of the mass of MXene nanosheets.

[0012] The present invention also provides a method for preparing the above-mentioned MXene-modified friction-responsive anti-corrosion coating suitable for alcohol-based fuel ships, comprising the following steps: (1) Preparation of MXene nanosheets: MAX phase ceramic powder was added to an etching solution for etching, and MXene nanosheet powder was obtained after post-treatment; (2) Supported second-phase catalyst: The MXene nanosheets obtained in step (1) are dispersed in a solvent, and a second-phase catalyst precursor and a reducing agent are added to react. After post-treatment, MXene modified powder supported on the second-phase catalyst is obtained. (3) Substrate pretreatment: The metal substrate is surface treated to obtain a pretreated substrate; (4) Coating preparation: The MXene modified powder obtained in step (2) is mixed with binder and dispersant in a liquid medium to form a coating slurry. The coating slurry is then applied to the surface of the pretreated substrate in step (3) and cured to form an MXene modified friction-responsive anti-corrosion coating on the surface of the metal substrate.

[0013] Further, in step (1), the MAX phase ceramic powder is one or more of Ti3AlC2, Mo2Ga2C, and Ti2AlC; the etching solution is a mixed solution of lithium fluoride and hydrochloric acid, wherein the concentration of hydrochloric acid is 8~10 mol / L, the concentration of lithium fluoride is 75~90 g / L, and the solid-liquid ratio of MAX phase ceramic powder to etching solution is 1 g:(15~25) mL; the etching temperature is 30~50℃, and the time is 24~48 h; the post-treatment includes centrifugal washing to neutrality, and obtaining MXene nanosheet powder by ultrasonic exfoliation and vacuum drying.

[0014] Further, in step (2), the solvent is oleylamine; the concentration of the MXene nanosheets in the solvent is 1~5 mg / mL; the second phase catalyst precursor is one or more of PdCl2, H2PdCl4, PtCl4, AgNO3, boric acid, and urea; the reducing agent is sodium borohydride or ascorbic acid, and its addition amount is 2~4 times the molar amount of the second phase catalyst precursor; the reaction is carried out at room temperature for 3~9 h; the post-treatment includes centrifugation, washing and vacuum drying.

[0015] Furthermore, in step (3), the metal substrate is carbon steel, stainless steel or copper alloy for alcohol-based fuel ships; the surface treatment includes grinding, degreasing, rust removal, water washing and drying in sequence.

[0016] Furthermore, in step (4), the binder is one or more of epoxy resin, polyimide, and silane coupling agent, and its addition amount is 20-50 wt% of the total mass of MXene nanosheets and the second phase catalyst; the dispersant is sodium dodecylbenzenesulfonate or polyethylene glycol, and its addition amount is 1-5 wt% of the mass of MXene modified powder; the liquid medium is deionized water, and the solid content of the coating slurry is 20-40 wt%.

[0017] Furthermore, in step (4), the coating method is spraying, brushing or dipping; the curing conditions are: air drying at room temperature for 1-2 hours, followed by constant temperature curing at 80-150℃ for 2-4 hours; the thickness of the obtained MXene modified friction-responsive anti-corrosion coating is 50-500μm.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention provides a friction-responsive intelligent anti-corrosion coating. Utilizing a second-phase catalyst loaded on the MXene surface, during relative friction between ship components, it actively catalyzes redox or decomposition reactions of alcohols in the friction environment, generating products with both lubricating and protective functions. Specifically, carbon-based products can form a lubricating film, filling micro-protrusions and friction scratches on the coating surface, effectively reducing the coefficient of friction and achieving dynamic friction reduction; oxide or polymer products can form a dense protective film, covering the coating surface, blocking contact between alcohol-based corrosive media, moisture, etc., and the metal substrate, inhibiting electrochemical corrosion and achieving active anti-corrosion function.

[0019] 2. This invention fully leverages the synergistic effect of MXene nanosheets and the second-phase catalyst. MXene nanosheets possess a high specific surface area and abundant surface functional groups, providing an ideal supporting substrate for the second-phase catalyst, achieving uniform dispersion and stable anchoring of the catalyst. Simultaneously, the layered structure of MXene can further block the penetration of corrosive media, and its high conductivity can reduce the potential difference between the coating and the substrate, reducing corrosion current, thus synergistically enhancing the anti-corrosion effect with the catalytic protection of the catalyst.

[0020] 3. This invention ingeniously transforms alcohol-based media from a "corrosion source" into a "protective source." Targeting the unique service environment of alcohol-fueled ships, it utilizes the alcohol itself as a reactant to generate protective products in situ under frictional triggering, achieving a "turning harm into benefit" technical effect and solving the dual problems of accelerated corrosion and insufficient lubrication caused by alcohol-based media.

[0021] 4. The preparation process of this invention is simple and cost-controllable, and the coating exhibits good frictional responsiveness and environmental adaptability. By controlling parameters such as catalyst type, loading, binder system, and coating thickness, differentiated responses to different alcohol media (methanol, ethanol) can be achieved. It is suitable for surface protection of metal components such as hulls, engines, and fuel lines of various alcohol-based fuel ships, and has broad application prospects.

[0022] 5. Compared with traditional physical barrier type anti-corrosion coatings, the coating provided by the present invention has the characteristics of active response and dynamic repair. It can generate a protective film in situ after friction damage occurs, significantly extend the service life of the coating, reduce maintenance costs, and provide a reliable guarantee for the long-term stable operation of alcohol-based fuel ships. Attached Figure Description

[0023] Figure 1 The images shown are XRD patterns of MAX, MXene, Ag / MXene, and Pd / / MXene in the embodiments of the present invention.

[0024] Figure 2 This is a SEM image of Pd / MXene obtained in an embodiment of the present invention.

[0025] Figure 3 This is a TEM image of Pd / MXene obtained in an embodiment of the present invention.

[0026] Figure 4 The friction coefficient curves of MXene and Pd / MXene coatings prepared in the embodiments of the present invention in a methanol / ethanol environment.

[0027] Figure 5 The polarization curves of MXene and Pd / / MXene obtained in the embodiments of the present invention are shown. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0029] This invention provides an MXene-modified tribologically responsive anti-corrosion coating suitable for alcohol-fueled ships. The coating is applied to a metal substrate surface and comprises MXene nanosheets and a second-phase catalyst supported on the surface of the MXene nanosheets. The second-phase catalyst catalyzes the reaction of alcohols (such as methanol and ethanol) to generate products with both lubricating and protective functions. The MXene nanosheets are preferably Ti3C2T. xThe catalyst is one or more of Mo2C and Ti2C, with a thickness of 1~10nm and a sheet diameter of 0.5~5μm; the second phase catalyst is preferably a metal catalyst such as Pd, Pt, Ni, Ag or a non-metal catalyst such as B, N, etc., with a loading of 1~10wt% of the mass of MXene nanosheets.

[0030] This invention also provides a method for preparing the above-mentioned coating, comprising four main steps: MXene nanosheet preparation, second-phase catalyst loading, substrate pretreatment, and coating preparation. Specific embodiments are provided below to further illustrate this invention.

[0031] Example 1: Pd / Ti3C2T x Preparation of composite coating (1)Ti3C2T x Preparation of MXene nanosheets A 9M HCl solution was prepared using deionized water and 12M concentrated hydrochloric acid. 3.2g LiF and 2g Ti3AlC2 (MAX phase) were weighed. First, 40mL of 9M HCl was mixed with 3.2g LiF and stirred for 15min under a 40℃ water bath. Then, Ti3AlC2 powder was slowly added, approximately 0.1-0.2g each time, and the mixture was stirred and reacted under a 40℃ water bath for 48h for etching. After the reaction, the solution was transferred to a centrifuge tube and centrifuged at 5000rpm for 1min, repeating this process 10-15 times. After each centrifugation, the supernatant was discarded, deionized water was added, and the mixture was shaken until the pH ≥ 6 and the supernatant turned black. The mixture was then shaken and centrifuged three more times, collecting the upper liquid to obtain Ti3C2T. x Solution. Ti3C2T x The solution was pre-frozen for 24 hours, and then freeze-dried in a freeze dryer for 48 hours to obtain Ti3C2T. x MXene nanosheet powder.

[0032] (2) Pd / Ti3C2T x Preparation Take 30 mg of MXene powder obtained in step (1), and add it together with 30 mg of sodium ascorbate, 10 mg of molybdenum hexacarbonyl and 20 mg of palladium acetylacetonate into 20 mL of oleylamine (OAm). Sonicate for 30 min to form a homogeneous solution. Then react in a water bath at 80 °C for 6 h. After the reaction is complete, wash the powder by centrifugation using 70% ethanol solution and a 1:1 (v / v) mixture of anhydrous ethanol and cyclohexane at 3500 rpm for 10 min, repeating the washing 2-3 times. Finally, vacuum dry at 60 °C for 4 h to obtain MXene modified powder supported on the Pd catalyst.

[0033] (3) Matrix pretreatment Take a 316 stainless steel sheet (20mm×20mm×3mm) and polish it with 100-grit, 400-grit, and 800-grit sandpaper in sequence until the surface roughness Ra reaches 0.3μm. Then clean it with deionized water and anhydrous ethanol in sequence, and blow it dry for later use.

[0034] (4) Coating preparation Take 5g of MXene modified powder obtained in step (2), add 1.2g of epoxy resin, 0.1g of sodium dodecylbenzenesulfonate and 10mL of deionized water, and ultrasonically disperse at 200W power for 20min. After stirring evenly, a coating slurry is obtained. The coating slurry is applied to the pretreated substrate surface obtained in step (3) by spraying. The spraying pressure is 0.4MPa and the spraying distance is 15cm. After drying at room temperature for 1.5h, it is placed in an oven and cured in stages: first, it is kept at 90℃ for 1.5h, and then the temperature is raised to 130℃ and kept at 1.5h. After curing, it is naturally cooled to room temperature to obtain an MXene modified friction-responsive anti-corrosion coating.

[0035] Example 2: Ag / Ti3C2T x Preparation of composite coating This embodiment is basically the same as Example 1, except that AgNO3 is used as the catalyst precursor in step (2). Specifically, an AgNO3 solution with a concentration of 1.25 mg / mL is prepared using deionized water, and an MXene solution with a concentration of 6.7 mg / mL is prepared using deionized water. The two solutions are mixed at a volume ratio of 1:4, stirred and reacted for 2 hours, and then centrifuged, washed, and dried to obtain Ag / MXene modified powder. The substrate pretreatment and coating preparation steps are the same as in Example 1.

[0036] Example 3: Pd / Ti3C2T with different binder systems x Composite coating preparation This embodiment is basically the same as Embodiment 1, except that the binder and dispersant are replaced in step (4). Specifically, 5g of MXene modified powder obtained in step (2) is taken, 1.5g of chitosan is weighed as the binder and 0.1g of polyethylene glycol is weighed as the dispersant, and they are dissolved together in 10mL of deionized water. The mixture is ultrasonicated at 200W for 30min and stirred evenly to obtain a coating slurry. After coating, it is air-dried at room temperature for 2h and then placed in an oven for staged curing: first, it is kept at 85℃ for 2h, and then the temperature is raised to 120℃ and kept at 120℃ for 2h. After curing, it is naturally cooled to room temperature to obtain an MXene modified friction-responsive anti-corrosion coating.

[0037] Example 4: Pd / Ti2CT x Preparation of composite coating This embodiment is basically the same as Embodiment 1, except that in step (1), Ti3AlC2 is replaced with Ti2AlC as the MAX phase precursor, and the etching time is shortened to 24h to obtain Ti2CT. x MXene nanosheets. Subsequent steps were the same as in Example 1 to prepare Pd / Ti2CT. x Composite coating.

[0038] Comparative Example 1 (Comparison with Existing Technologies) A method for preparing a Pd-based alloy-supported catalyst includes: dispersing plate-like MXene material in an acidic solution, adding a nitrogen-containing precursor, stirring and separating, washing to neutral, and calcining to obtain nitrogen-doped plate-like MXene material; dispersing nitrogen-doped plate-like MXene in deionized water, dispersing carbon nanotubes in ethanol, mixing and stirring at room temperature, separating and drying to obtain nitrogen-doped plate-like MXene / carbon nanotubes; adjusting the pH of sodium molybdate solution to acidic using hydrochloric acid solution, adding L-cysteine, ultrasonically treating, adding nitrogen-doped plate-like MXene / carbon nanotubes, hydrothermal reaction, cooling and separating, washing and drying to obtain a nitrogen-doped plate-like MXene / carbon nanotube / molybdenum disulfide composite material; ultrasonically dispersing the composite material in deionized water, adding H2PdCl4, Cu(NO3)2, and Co(NO3)2, adding a reducing agent dropwise while stirring, stirring in a water bath until the reaction is complete, separating and washing to neutral, and freeze-drying to obtain a Pd-based alloy-supported catalyst.

[0039] Comparative Example 2 (Comparison with Existing Technologies) A method for preparing a two-dimensional layered ammonia oxidation catalyst based on MXene includes: using MAX as a precursor, adding fluoride and acid for in-situ HF etching; centrifuging the etching product with deionized water at low to medium speed until the solution becomes turbid and the pH value reaches above 6; then ultrasonically dispersing the precipitate in a solvent, filtering, rinsing with deionized water, and vacuum drying to obtain accordion-shaped MXenes; at room temperature, ultrasonically dispersing the accordion-shaped MXenes in a mixture of isopropanol and deionized water, adding a transition metal precursor and stirring to mix, then reducing with NaBH4 alkaline solution, followed by filtration and vacuum drying to obtain an MXene-supported transition metal catalyst.

[0040] Structural characterization and performance evaluation of the product prepared in Example 1: Structural and morphological characterization X-ray diffraction (XRD) analysis was performed on the MAX phase, MXene, Ag / MXene, and Pd / MXene samples prepared in Example 1. The results are as follows: Figure 1As shown in the figure, the characteristic peaks of MXene changed significantly relative to the MAX phase after etching, indicating that MXene was successfully etched. After loading Ag and Pd, the characteristic peaks of MXene remained unchanged, and corresponding metal diffraction peaks appeared, confirming that the second-phase catalyst was successfully loaded onto the MXene surface.

[0041] The Pd / MXene sample prepared in Example 1 was observed by scanning electron microscopy (SEM), and the results are as follows: Figure 2 As shown in the figure, Pd nanoparticles are uniformly distributed on the surface of MXene nanosheets, with relatively uniform particle size and no obvious aggregation.

[0042] The Pd / MXene sample prepared in Example 1 was observed by transmission electron microscopy (TEM), and the results are as follows: Figure 3 As shown in the figure, the layered structure of MXene and the Pd nanoparticles loaded on the surface can be clearly seen. The particle size is about 5~10nm and they are uniformly dispersed.

[0043] Friction performance test The tribological properties of the MXene coating and Pd / MXene coating prepared in Example 1 were tested using a reciprocating tribometer. The test parameters were: load 1 N, frequency 1 Hz, stroke 5 mm, 6 mm diameter 304 stainless steel balls used as the mating balls, ambient temperature 25 ± 1 °C, and a methanol or ethanol atmosphere. The test results are as follows: Figure 3 As shown.

[0044] from Figure 4 It can be seen that in a methanol environment, the friction coefficient of the pure MXene coating is approximately 0.33, while the friction coefficient of the Pd / MXene composite coating decreases to approximately 0.22; in an ethanol environment, the friction coefficient of the pure MXene coating is approximately 0.30, while the friction coefficient of the Pd / MXene composite coating decreases to approximately 0.16. The results indicate that after loading with a Pd catalyst, the composite coating exhibits significant responsiveness to alcohols in the friction environment, catalyzing the reaction of alcohols to generate lubricating products, significantly reducing the friction coefficient, and achieving a friction-reducing effect.

[0045] Electrochemical corrosion performance test Polarization curves of the MXene coating and Pd / MXene coating prepared in Example 1 were measured using an electrochemical workstation. The test medium was 3.5 wt% NaCl solution, and the scan rate was 1 mV / s. The test results are as follows: Figure 5 As shown.

[0046] from Figure 5It can be seen that the corrosion potential of the Pd / MXene composite coating is significantly more positive than that of the pure MXene coating, and the corrosion current density is significantly reduced. This indicates that the Pd / MXene composite coating has superior corrosion resistance, and the supported Pd catalyst and MXene work synergistically to effectively block the penetration of corrosive media and inhibit the occurrence of electrochemical corrosion reactions.

[0047] Comparison of different catalyst systems The friction and corrosion properties of the composite coatings prepared in Example 1 (Pd / MXene) and Example 2 (Ag / MXene) were compared. The results showed that both catalyst systems could effectively reduce the friction coefficient and improve corrosion resistance. The Pd / MXene system exhibited slightly better catalytic activity than the Ag / MXene system in a methanol environment, which is consistent with the high catalytic activity of Pd for alcohol oxidation.

[0048] Comparison of different adhesive systems The composite coatings prepared in Example 1 (epoxy resin binder) and Example 3 (chitosan binder) were subjected to adhesion and friction performance tests. The results showed that both binder systems could form uniform and stable coatings with good adhesion. The chitosan system has certain advantages in terms of environmental friendliness, while the epoxy resin system performs better in terms of mechanical properties and resistance to media. The appropriate binder system can be selected according to the specific application scenario.

[0049] Comparison of different MXene materials For Example 1 (Ti3C2T) x (Base) and Example 4 (Ti2CT) x The performance of composite coatings prepared by (based on) was compared. The results showed that both MXene materials could successfully support Pd catalysts and achieve triboelectric response; Ti3C2T x Due to its higher surface functional groups and larger specific surface area, Ti2CT exhibits a slightly higher catalyst loading and a slightly better triboelectric response. x The preparation process is simpler and the cost is lower.

[0050] In summary, the MXene-modified tribologically responsive anti-corrosion coating provided by this invention, by loading a second-phase catalyst with catalytic function onto the surface of MXene nanosheets, can generate lubrication and protective products in situ in alcohol media under friction triggering, achieving the dual effects of dynamic friction reduction and active corrosion resistance. This coating has a simple preparation process, strong responsiveness, and is suitable for surface protection of metal components of various alcohol-based fuel ships, showing broad application prospects.

[0051] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art can make various improvements and modifications without departing from the spirit and principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An MXene-modified tribologically responsive anti-corrosion coating suitable for alcohol-fueled ships, characterized in that, The coating is applied to the surface of the metal substrate, including: MXene nanosheets; and a second-phase catalyst supported on the surface of the MXene nanosheets; the loading of the second-phase catalyst is 1~10 wt% of the mass of the MXene nanosheets. The second phase catalyst can catalyze the reaction of alcohols to generate lubricating and / or protective products.

2. The MXene-modified tribologically responsive anti-corrosion coating for alcohol-fueled ships according to claim 1, characterized in that, The second phase catalyst is one or a mixture of two of the following: a metal catalyst and a non-metal catalyst; the metal catalyst is one or more of Pd, Pt, Ni, and Ag; and the non-metal catalyst is one or two of B and N.

3. The MXene-modified tribologically responsive anti-corrosion coating suitable for alcohol-fueled ships according to claim 1 or 2, characterized in that, The MXene nanosheets are Ti3C2T x One or more of Mo2C and Ti2C, with a thickness of 1~10nm and a flake diameter of 0.5~5μm; the Ti3C2T x The end groups on the surface are one or more of -O, -OH, and -F.

4. A method for preparing an MXene-modified friction-responsive anti-corrosion coating suitable for alcohol-based fuel vessels as described in any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Preparation of MXene nanosheets: MAX phase ceramic powder was added to an etching solution for etching, and MXene nanosheet powder was obtained after post-treatment; (2) Supported second-phase catalyst: The MXene nanosheets obtained in step (1) are dispersed in a solvent, and a second-phase catalyst precursor and a reducing agent are added to react. After post-treatment, MXene modified powder supported on the second-phase catalyst is obtained. (3) Substrate pretreatment: The metal substrate is surface treated to obtain a pretreated substrate; (4) Coating preparation: The MXene modified powder obtained in step (2) is mixed with binder and dispersant in a liquid medium to form a coating slurry. The coating slurry is then applied to the surface of the pretreated substrate in step (3) and cured to form an MXene modified friction-responsive anti-corrosion coating on the surface of the metal substrate.

5. The preparation method according to claim 4, characterized in that, In step (1), the MAX phase ceramic powder is one or more of Ti3AlC2, Mo2Ga2C, and Ti2AlC; the etching solution is a mixed solution of lithium fluoride and hydrochloric acid, wherein the concentration of hydrochloric acid is 8~10 mol / L, the concentration of lithium fluoride is 75~90 g / L, and the solid-liquid ratio of MAX phase ceramic powder to etching solution is 1 g: (15~25) mL; the etching temperature is 30~50℃, and the time is 24~48 h; the post-treatment includes centrifugal washing to neutrality, and obtaining MXene nanosheet powder by ultrasonic exfoliation and vacuum drying.

6. The preparation method according to claim 4, characterized in that, In step (2), the solvent is oleylamine; the concentration of the MXene nanosheets in the solvent is 1~5 mg / mL; the second phase catalyst precursor is one or more of PdCl2, H2PdCl4, PtCl4, AgNO3, boric acid, and urea; the reducing agent is sodium borohydride or ascorbic acid, and its addition amount is 2~4 times the molar amount of the second phase catalyst precursor; the reaction is carried out at room temperature for 3~9 h; the post-treatment includes centrifugation, washing and vacuum drying.

7. The preparation method according to claim 4, characterized in that, In step (3), the metal substrate is carbon steel, stainless steel or copper alloy for alcohol-based fuel ships; the surface treatment includes grinding, degreasing, rust removal, water washing and drying in sequence.

8. The preparation method according to claim 4, characterized in that, In step (4), the binder is one or more of epoxy resin, polyimide, and silane coupling agent, and its addition amount is 20-50 wt% of the total mass of MXene nanosheets and second-phase catalyst; the dispersant is sodium dodecylbenzenesulfonate or polyethylene glycol, and its addition amount is 1-5 wt% of the mass of MXene modified powder; the liquid medium is deionized water, and the solid content of the coating slurry is 20-40 wt%.

9. The preparation method according to claim 5, characterized in that, In step (4), the coating method is spraying, brushing or dipping; the curing conditions are: air drying at room temperature for 1-2 hours, followed by constant temperature curing at 80-150℃ for 2-4 hours; the thickness of the obtained MXene modified friction-responsive anti-corrosion coating is 50-500μm.

Images