F-ZIF-8 / PVDF / FP multifunctional intelligent coating, and preparation method and application thereof

Abstract

The application discloses an F-ZIF-8 / PVDF / FP multifunctional intelligent coating and a preparation method and application thereof, and belongs to the technical field of metal material surface protection. 3+ The fluorescent probe is compounded and dip-coated on the aluminum alloy base material to obtain the coating. The coating prepared by the application has a micro-nano hierarchical rough structure, a static water contact angle greater than 150°, a rolling angle less than 5°, and super-hydrophobicity, self-cleaning, long-term corrosion resistance and mechanical stability; meanwhile, the Al 3+ The specific fluorescent probe can realize in-situ and visual monitoring and early warning of aluminum alloy corrosion through fluorescence signal change when the coating is damaged. The preparation method is simple, the condition is mild, and the application is suitable for metal components with complex shapes, so the application has a good application prospect in the fields of super-hydrophobic coating, corrosion-resistant coating and in-situ corrosion monitoring.

Description

Technical Field

[0001] This invention belongs to the field of metal material surface protection technology, specifically relating to a multifunctional intelligent coating of F-ZIF-8 / PVDF / FP that integrates superhydrophobicity, long-term corrosion protection, mechanical stability and in-situ visual monitoring of corrosion, as well as its preparation method and application. Background Technology

[0002] Metal corrosion is a critical issue affecting the service safety and lifespan of marine engineering, aerospace, and new energy equipment. Inspired by dandelions, superhydrophobic coatings, through the construction of micro-nano rough structures and low surface energy modification, can form an air cushion layer to block corrosive media, thus significantly slowing down the metal corrosion process and providing a new approach to metal protection. Among these, metal-organic frameworks (MOFs), as porous crystalline materials with high specific surface area, tunable structure, and good chemical stability, offer new ideas for constructing high-performance functional coatings. Zeolite imidazole ester frameworks (ZIFs), as an important branch of MOFs, especially ZIF-8, show great potential in anti-corrosion coatings due to their excellent hydrophobicity, thermal stability, and ease of functionalization. Previous studies have successfully constructed coating systems with excellent anti-corrosion and superhydrophobic properties on magnesium and aluminum alloy surfaces by combining ZIF-8 with micro-arc oxidation layers and polymer matrices.

[0003] Superhydrophobic coating technology offers a new solution for the protection of metallic materials due to its unique advantages. By constructing micro-nano rough structures and modifying surfaces with low surface energy, superhydrophobic coatings can significantly enhance the waterproof and corrosion-resistant properties of material surfaces. While existing technologies have explored the use of ZIF-8 to enhance the corrosion resistance and hydrophobicity of coatings, most studies focus on performance improvement. The protective performance of these coating systems declines sharply after mechanical damage, making it difficult to achieve long-term protection for metallic materials. Furthermore, they cannot simultaneously monitor the corrosion process in real-time and in-situ, thus failing to provide early warning capabilities.

[0004] Despite the numerous advantages of superhydrophobic coating technology, existing systems still face many challenges. Existing preparation methods have certain defects and cannot meet current needs. There is an urgent need to develop a method for preparing multifunctional smart coatings that is convenient to prepare, has excellent hydrophobicity and anti-corrosion properties, and can simultaneously monitor the corrosion process in real time. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an F-ZIF-8 / PVDF / FP multifunctional smart coating, its preparation method, and its application. This coating mimics the micro-nano hierarchical structure and hydrophobic silver mirror response mechanism of dandelion, possessing not only excellent superhydrophobicity, self-cleaning properties, mechanical stability, and long-term corrosion resistance, but also introducing ion-specific fluorescent probes to achieve in-situ, visualized, real-time monitoring and early warning of the corrosion process of metal substrates.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for preparing an F-ZIF-8 / PVDF / FP multifunctional smart coating, comprising the following steps: (1) Preparation of F-ZIF-8 / PVDF material: ZIF-8 was dissolved in anhydrous ethanol and 25% ammonia solution, then TEOS was added and stirred until homogeneous. PVDF and PFDTES were then added and stirred until homogeneous to obtain an F-ZIF-8 / PVDF nanoparticle suspension. (2) Preparation of F-ZIF-8 / PVDF / FP multifunctional smart coating: The F-ZIF-8 / PVDF nanoparticle suspension was dispersed in anhydrous ethanol, and Al was added. 3+ The fluorescent probe was stirred evenly to obtain an F-ZIF-8 / PVDF / FP mixture, which was then dipped onto a pretreated aluminum alloy substrate to obtain an F-ZIF-8 / PVDF / FP multifunctional smart coating.

[0007] Further, in step (1), the ZIF-8 is prepared by adding Zn(NO3)2·6H2O to methanol and stirring until completely dissolved to obtain Zn 2+ Methanol solution; add 2-MIM to methanol and stir until completely dissolved to obtain a 2-MIM methanol solution, then add Zn 2+ Methanol solution was slowly added to 2-MIM methanol solution, and the reaction was continuously stirred magnetically at room temperature. During the reaction, a white precipitate was gradually formed. After the reaction was completed, the precipitate was centrifuged, washed, and vacuum dried to obtain ZIF-8 nanoparticles.

[0008] As a preferred option, Zn is configured 2+ The ratio of Zn(NO3)2·6H2O to methanol in the methanol solution is 0.9g:33g.

[0009] Preferably, the ratio of 2-MIM to methanol in the preparation of the 2-MIM methanol solution is 1.97 g: 33 g.

[0010] As a preferred method, the magnetic stirring reaction time is 24 hours, the centrifugation is carried out at 8000 rpm for 10 minutes, the precipitate is washed three times with methanol, and the vacuum drying temperature is 60℃ for 12 hours.

[0011] Furthermore, in step (1), the ratio of ZIF-8, anhydrous ethanol, ammonia, TEOS, PVDF and PFDTES is (0.1-0.4) g: 11 mL: 1.5 mL: 0.25 mL: 1 g: 0.2 mL.

[0012] Furthermore, in step (2), the F-ZIF-8 / PVDF nanoparticle suspension and Al 3+ The mass ratio of the fluorescent probe is 100:1.

[0013] Further, in step (2), the Al 3+ The fluorescent probe is 8-hydroxyquinoline.

[0014] Furthermore, the pretreated aluminum alloy substrate is obtained by sequentially polishing the aluminum alloy substrate with 800-grit, 1000-grit, and 2000-grit sandpaper, then sequentially ultrasonically cleaning it with anhydrous ethanol and acetone for 10 minutes each, and drying it at 60°C for 30 minutes.

[0015] Preferably, the aluminum alloy substrate is 6061 aluminum alloy.

[0016] Secondly, the present invention provides an F-ZIF-8 / PVDF / FP multifunctional smart coating prepared by the above-mentioned preparation method. In the F-ZIF-8 / PVDF / FP multifunctional smart coating, ZIF-8 nanoparticles with a regular octahedral shape and a micro-nano rough structure obtained by fluorinating ZIF-8 nanoparticles with PFDTES are present. PVDF forms a flexible bonding network, and Al... 3+ The fluorescent probe is uniformly dispersed within it.

[0017] Thirdly, the present invention also provides the application of the above-mentioned F-ZIF-8 / PVDF / FP multifunctional smart coating in aluminum alloy superhydrophobic coating, anti-corrosion coating, and in-situ identification and monitoring of corrosion.

[0018] Compared with the prior art, the beneficial technical effects of the present invention are: (1) The micro-nano rough structure constructed by fluorinating ZIF-8 in this invention, in synergy with low surface energy materials and binders, endows the coating with an extremely high static contact angle (>150°) and an extremely low roll-off angle (<5°), and exhibits excellent chemical and mechanical stability. Electrochemical tests show that the coating can significantly improve the corrosion resistance of the aluminum alloy substrate, and the low-frequency impedance modulus is increased by more than three orders of magnitude.

[0019] (2) The F-ZIF-8 / PVDF / FP multifunctional smart coating prepared in this invention introduces Al 3+ Fluorescent probes can provide in-situ visual early warning of substrate corrosion by detecting changes in fluorescence intensity when coating damage leads to corrosion of the aluminum alloy substrate.

[0020] (3) The preparation method of the F-ZIF-8 / PVDF / FP multifunctional intelligent coating described in this invention is simple and mild, and can be applied to aluminum alloy components with complex shapes. Furthermore, this invention successfully integrates functions such as superhydrophobicity, self-cleaning, long-term active corrosion protection, excellent mechanical stability, and in-situ intelligent corrosion monitoring into a single coating system, and has good application prospects in the fields of superhydrophobic coatings, anti-corrosion coatings, and in-situ corrosion identification and monitoring of aluminum alloys. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the preparation process of the F-ZIF-8 / PVDF / FP multifunctional smart coating of the present invention.

[0022] Figure 2 The images shown are scanning electron microscope (SEM) images of the materials prepared in Example 1; where (a) is a SEM image of ZIF-8 nanoparticles and (b) is a SEM image of the F-ZIF-8 / PVDF / PF coating.

[0023] Figure 3 The electrochemical test curves of the F-ZIF-8 / PVDF coating prepared in Example 1, 6061 aluminum alloy, F-SiO2 / PVDF and F-ZIF-8 / SiO2 / PVDF coating in 3.5wt.% NaCl solution are compared. (a) is the Nyquist plot, (b) is the Bode plot and (c) is the phase angle plot.

[0024] Figure 4 The electrochemical test curves of F-ZIF-8 / PVDF coatings with different ZIF-8 contents (0.1 g, 0.2 g, 0.3 g, 0.4 g) on ​​6061 aluminum alloy substrate in 3.5 wt.% NaCl solution are compared. (a) is the Nyquist plot, (b) is the Bode plot, and (c) is the phase angle plot.

[0025] Figure 5 The electrochemical test curves of the F-ZIF-8 / PVDF coating in Example 1 after undergoing different cycles of sandpaper abrasion and tape peeling are shown. (a) is the Nyquist plot, (b) is the Bode plot, and (c) is the phase angle plot.

[0026] Figure 6 The curves showing the changes in wetting properties of the F-ZIF-8 / PVDF coating in Example 1 after undergoing different cycles of sandpaper abrasion and tape peeling are shown. (a) is the curve showing the change in water contact angle, and (b) is the curve showing the change in roll-off angle.

[0027] Figure 7These are fluorescence monitoring images of the F-ZIF-8 / PVDF / PF coating in Example 1 after it was artificially scratched and immersed in 3.5 wt.% NaCl solution for different times. Among them, (a) shows Al 3+ The fluorescence changes of the probe to different ions, (b) are fluorescence monitoring photos of the F-ZIF-8 / PVDF / FP coating after it was scratched and then immersed in 3.5 wt.% NaCl solution for different times. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0029] In this invention, ZIF-8 is zeolitic imidazolate framework-8, 2-MIM is 2-methylimidazole, TEOS is tetraethyl orthosilicate, PFDTES is 1H,1H,2H,2H-perfluorodecyltriethoxysilane, and PVDF is polyvinylidene fluoride.

[0030] Example 1 Please see Figure 1 The preparation method of the F-ZIF-8 / PVDF / FP multifunctional smart coating provided in this embodiment includes the following specific steps: (1) Preparation of ZIF-8: Accurately weigh 0.9g of Zn(NO3)2·6H2O, add it to 33g of methanol, and stir magnetically for 30 minutes until completely dissolved to obtain transparent Zn. 2+ Methanol solution; separately weigh 1.97 g of 2-MIM, dissolve it in 33 g of methanol, and stir for 30 min until clear to obtain a 2-MIM methanol solution; add Zn 2+ Methanol solution was slowly poured into 2-MIM methanol solution and magnetically stirred continuously at room temperature for 24 hours. During the reaction, a white precipitate was gradually formed. After the reaction was completed, the mixture was transferred to a centrifuge tube and centrifuged at 8000 rpm for 10 minutes. The precipitate was washed three times with methanol to remove unreacted raw materials. The precipitate was then dried in a vacuum drying oven at 60℃ for 12 hours to obtain ZIF-8 nanoparticles.

[0031] (2) Preparation of F-ZIF-8 / PVDF nanoparticle suspension: Measure 11 mL of anhydrous ethanol and 1.5 mL of 25% ammonia solution, mix them thoroughly, add 0.25 mL of LTEOS, and stir magnetically for 30 min until evenly dispersed. Add 0.4 g of ZIF-8 nanoparticles to the mixture and continue stirring magnetically at room temperature for 1 h. Then add 0.2 mL of PFDTES and 1 g of PVDF sequentially, stir ultrasonically for 30 min, and then stir magnetically for 60 min to form a uniform and stable F-ZIF-8 / PVDF nanoparticle suspension.

[0032] (3) Preparation of F-ZIF-8 / PVDF / FP multifunctional smart coating: Take the above F-ZIF-8 / PVDF nanoparticle suspension and add 8-hydroxyquinoline at a mass ratio of 100:1. Stir at room temperature for 1 hour to mix evenly to obtain F-ZIF-8 / PVDF / FP mixed solution. Polish a 6061 aluminum alloy substrate with a specification of 25mm×10mm×1mm with 800-grit, 1000-grit, and 2000-grit sandpaper in sequence. Then, ultrasonically clean it in ethanol and acetone for 10 minutes and dry it at 60℃ for 30 minutes to obtain the pretreated 6061 aluminum alloy substrate.

[0033] The pretreated 6061 aluminum alloy substrate was vertically immersed in an F-ZIF-8 / PVDF nanoparticle suspension, held for 3 seconds, and then slowly lifted out at a speed of 5 mm / s. It was then left at room temperature for 5 minutes, and finally transferred to a 60℃ forced-air drying oven for curing for 12 hours to obtain a product without identified Al. 3+ The probe has an F-ZIF-8 / PVDF coating.

[0034] The pretreated 6061 aluminum alloy substrate was vertically immersed in the F-ZIF-8 / PVDF / FP mixture, held for 3 seconds, and then slowly lifted out at a speed of 5 mm / s. After being placed at room temperature for 5 minutes, it was then transferred to a 60℃ forced-air drying oven for curing for 12 hours to obtain the F-ZIF-8 / PVDF / FP multifunctional smart coating.

[0035] Example 2 The preparation method of F-ZIF-8 / PVDF coating in Example 2 is basically the same as that in Example 1, except that the content of ZIF-8 is replaced with 0.1g to prepare a uniform F-ZIF-8-1 / PVDF nanoparticle suspension.

[0036] Example 3 The preparation method of F-ZIF-8 / PVDF coating in Example 3 is basically the same as that in Example 1, except that the content of ZIF-8 is replaced with 0.2g to prepare a uniform F-ZIF-8-2 / PVDF nanoparticle suspension.

[0037] Example 4 The preparation method of F-ZIF-8 / PVDF coating in Example 4 is basically the same as that in Example 1, except that the content of ZIF-8 is replaced with 0.3g to prepare a uniform F-ZIF-8-1 / PVDF nanoparticle suspension.

[0038] Comparative Example 1 The preparation method of the F-ZIF-8 / PVDF coating in Comparative Example 1 is basically the same as that in Example 1, except that ZIF-8 is replaced with an equal amount of SiO2 to prepare the F-SiO2 / PVDF coating. The preparation method of the F-SiO2 / PVDF coating includes the following steps: Preparation of F-SiO2 / PVDF coating: 44 mL of anhydrous ethanol and 6 mL of 25% ammonia water were mixed evenly, and 1.0 mL of LTEOS was added. The mixture was magnetically stirred for 30 min until it was evenly dispersed. 0.4 g of SiO2 nanoparticles were added to the mixture and magnetically stirred for 1 h at room temperature. Then 0.8 mL of PFDTES and 4 g of PVDF were added sequentially, and the mixture was ultrasonically stirred for 30 min and then magnetically stirred for 60 min to form a uniform and stable F-SiO2 nanoparticle suspension. The F-SiO2 / PVDF coating was obtained by dip coating on the pretreated 6061 aluminum alloy substrate.

[0039] Comparative Example 2 The preparation method of the F-ZIF-8 / PVDF coating in Comparative Example 2 is basically the same as that in Example 1, except that ZIF-8 is replaced with ZIF-8 and SiO2 to prepare the F-ZIF-8 / SiO2 / PVDF coating. The preparation method of the F-ZIF-8 / SiO2 / PVDF coating includes the following steps: (1) Preparation of ZIF-8: Accurately weigh 0.9g of Zn(NO3)2·6H2O, add it to 33g of methanol, and stir magnetically for 30 minutes until completely dissolved to obtain transparent Zn. 2+ A methanol solution of Zn; separately weigh 1.97 g of 2-MIM, dissolve it in 33 g of methanol, and stir for 30 min until clear to obtain a 2-MIM methanol solution; 2+ The methanol solution was slowly poured into the 2-MIM methanol solution, and the mixture was continuously stirred magnetically at room temperature for 24 hours. During the reaction, a white precipitate was gradually formed. After the reaction was completed, the mixture was transferred to a centrifuge tube and centrifuged at 8000 rpm for 10 minutes. The precipitate was washed three times with methanol to remove unreacted raw materials. The precipitate was then dried in a vacuum drying oven at 60℃ for 12 hours to obtain ZIF-8 nanoparticles.

[0040] (2) Preparation of F-ZIF-8 / SiO2 / PVDF coating: Measure 44 mL of anhydrous ethanol and 6 mL of 25% ammonia water, mix them evenly, add 1.0 mL of TEOS, and stir magnetically for 30 min until evenly dispersed; add 0.2 g of ZIF-8 nanoparticles and 0.2 g of SiO2 nanoparticles with a particle size of 100 nm-200 nm to the above mixture, and continue to stir magnetically at room temperature for 1 h; then add 0.8 mL of PFDTES and 4 g of PVDF binder in sequence, stir ultrasonically for 30 min, and then stir magnetically for 60 min to form a uniform and stable F-ZIF-8 / SiO2 / PVDF nanoparticle suspension, and dip-coat the pretreated 6061 aluminum alloy substrate to obtain an F-ZIF-8 / SiO2 / PVDF coating.

[0041] The water contact angle and roll-off angle of the coatings prepared in Examples 1-4 and Comparative Examples 1-2 were tested, and the specific test results are shown in Table 1.

[0042] Table 1 Water contact angle and roll-off angle for different coatings

[0043] Please see Figure 2 , Figure 2 (a) is a SEM image of the ZIF-8 nanoparticles prepared in Example 1, showing their regular octahedral morphology; Figure 2 (b) shows the surface morphology of the F-ZIF-8 / PVDF / FP multifunctional smart coating, demonstrating its micro-nano hierarchical rough structure.

[0044] Electrochemical performance testing Figure 3 A comparison of electrochemical impedance spectroscopy (EIS) spectra of 6061 aluminum alloy, F-SiO2 / PVDF, F-ZIF-8 / PVDF, and F-ZIF-8 / SiO2 / PVDF coatings in 3.5 wt.% NaCl solution is presented. Figure 3 (a) The Nyquist plot shows that the F-ZIF-8 / PVDF coating has the largest impedance arc radius and the most regular profile, far exceeding the blank 6061 aluminum alloy, F-SiO2 / PVDF coating and F-ZIF-8 / SiO2 / PVDF composite coating. Figure 3 (b) Bode diagram and Figure 3 (c) The phase angle diagram further confirms that the impedance modulus of the F-ZIF-8 / PVDF coating reaches 1.70 × 10⁻⁶ in the low-frequency region. 5 Ω·cm 2 Higher than bare Al's 2.18 × 10⁻⁶. 3 Ω·cm 2 4.72×10⁻⁶ F-SiO₂ / PVDF coating 4 Ω·cm 2The 1.11×10⁻⁶ of the F-ZIF-8 / SiO₂ / PVDF composite coating 5 Ω·cm 2 Furthermore, the phase angle is wider and the peak value is higher in the mid-to-high frequency range, indicating that its structural integrity is the best and its corrosion resistance is optimal.

[0045] Figure 4 The effect of different ZIF-8 contents (0.1 g, 0.2 g, 0.3 g, 0.4 g) on ​​the corrosion resistance of F-ZIF-8 / PVDF coatings was demonstrated. Figure 4 As can be seen from (a)-(c), when the ZIF-8 content is 0.4 g, the low-frequency impedance modulus of the coating is as high as 4.75 × 10⁻⁶. 5 Ω·cm 2 The peak phase angle is close to 70°, which is significantly better than coatings with other ZIF-8 contents (0.1 g, 0.2 g, 0.3 g), indicating that 0.4 g of ZIF-8 is the optimal addition amount for the coating.

[0046] Mechanical stability test Figure 5 The electrochemical performance of the F-ZIF-8 / PVDF coating of Example 1 after undergoing different cycles of sandpaper abrasion and tape peeling is demonstrated. Figure 5 It can be seen that after 800 sandpaper abrasion cycles and 140 tape peeling cycles, although the impedance modulus of the coating decreased, it was still two orders of magnitude higher than that of the blank 6061 aluminum alloy, and it can maintain a high corrosion protection capability.

[0047] Figure 6 The changes in wetting properties of the F-ZIF-8 / PVDF coating of Example 1 after undergoing different cycles of sandpaper abrasion and tape peeling are shown. Figure 6 It can be seen that after 800 sandpaper abrasion cycles and 140 tape peeling cycles, the water contact angle of the coating still remains above 150°, and the roll-off angle increases slightly but is still less than 5°, indicating that the coating has excellent mechanical stability. This is mainly due to the strong adhesion of the PVDF adhesive to ZIF-8.

[0048] In-situ corrosion monitoring performance test Figure 7 The images show fluorescence monitoring of the F-ZIF-8 / PVDF / FP coating of Example 1 after it was artificially scratched and then immersed in 3.5 wt.% NaCl solution for different times, demonstrating the fluorescence enhancement process. Figure 7 (a) indicates that Al 3+ Fluorescent probes for Al 3+ Specific fluorescence changes. From Figure 7 As can be seen in (b), it contains Al 3+The fluorescence intensity of the fluorescent probe coating gradually increased, eventually reaching a strong fluorescence intensity after immersion in 3.5 wt.% NaCl solution for 10 days. This fluorescence originates from Al. 3+ Fluorescent groups and metal corrosion at defect interfaces can produce Al. 3+ Furthermore, the fluorescent group and the specific Al-based 3+ Ion recognition enables fluorescence enhancement. For deeper scratches, the 6061 aluminum alloy substrate is directly exposed to the corrosive medium, leading to an electrochemical corrosion reaction at the metal-coating interface. In this case, the fluorescent probe targets the Al... 3+ The presence of Al is specifically identified and associated with Al 3+ The binding leads to enhanced fluorescence. Therefore, Al-containing... 3+ The corrosion dynamics of the F-ZIF-8 / PVDF / FP superhydrophobic coating of the fluorescent probe can be monitored by fluorescence response behavior.

[0049] The above description is a preferred embodiment of the present invention, used to explain the technical solution of the present invention, and is not intended to limit the present invention. Those skilled in the art can make conventional modifications, equivalent substitutions and improvements within the spirit and principles of the present invention, all of which are still included within the protection scope of the present invention.

Claims

1. A method for preparing an F-ZIF-8 / PVDF / FP multifunctional smart coating, characterized in that, Includes the following steps: (1) Preparation of F-ZIF-8 / PVDF material: ZIF-8 was dissolved in anhydrous ethanol and 25% ammonia solution, then TEOS was added and stirred until homogeneous. PVDF and PFDTES were then added and stirred until homogeneous to obtain an F-ZIF-8 / PVDF nanoparticle suspension. (2) Preparation of F-ZIF-8 / PVDF / FP multifunctional smart coating: The F-ZIF-8 / PVDF nanoparticle suspension was dispersed in anhydrous ethanol, and Al was added. 3+ The fluorescent probe was stirred evenly to obtain an F-ZIF-8 / PVDF / FP mixture, which was then dipped onto a pretreated aluminum alloy substrate to obtain an F-ZIF-8 / PVDF / FP multifunctional smart coating.

2. The method for preparing an F-ZIF-8 / PVDF / FP multifunctional smart coating according to claim 1, characterized in that: In step (1), the ZIF-8 is prepared by adding Zn(NO3)2·6H2O to methanol and stirring until completely dissolved to obtain Zn 2+ Methanol solution; add 2-MIM to methanol and stir until completely dissolved to obtain a 2-MIM methanol solution, then add Zn 2+ Methanol solution was slowly added to 2-MIM methanol solution, and the reaction was continuously stirred magnetically at room temperature. During the reaction, a white precipitate was gradually formed. After the reaction was completed, the precipitate was centrifuged, washed, and vacuum dried to obtain ZIF-8 nanoparticles.

3. The method for preparing an F-ZIF-8 / PVDF / FP multifunctional smart coating according to claim 2, characterized in that: Configure Zn 2+ The ratio of Zn(NO3)2·6H2O to methanol in the methanol solution was 0.9 g:33 g; the ratio of 2-MIM to methanol in the 2-MIM methanol solution was 1.97 g:33 g; the reaction time was 24 h with magnetic stirring; centrifugation was performed at 8000 rpm for 10 min; the precipitate was washed three times with methanol; and vacuum drying was performed at 60 °C for 12 h.

4. The method for preparing an F-ZIF-8 / PVDF / FP multifunctional smart coating according to claim 1, characterized in that: In step (1), the ratio of ZIF-8, anhydrous ethanol, ammonia, TEOS, PVDF and PFDTES is (0.1-0.4) g: 11 mL: 1.5 mL: 0.25 mL: 1 g: 0.2 mL.

5. The method for preparing an F-ZIF-8 / PVDF / FP multifunctional smart coating according to claim 1, characterized in that: In step (2), the F-ZIF-8 / PVDF nanoparticle suspension and Al 3+ The mass ratio of the fluorescent probe is 100:

1.

6. The method for preparing an F-ZIF-8 / PVDF / FP multifunctional smart coating according to claim 1, characterized in that: In step (2), the Al 3+ The fluorescent probe is 8-hydroxyquinoline.

7. The method for preparing an F-ZIF-8 / PVDF / FP multifunctional smart coating according to claim 1, characterized in that: The pretreated aluminum alloy substrate was obtained by sequentially polishing the aluminum alloy substrate with 800-grit, 1000-grit, and 2000-grit sandpaper, then ultrasonically cleaning it with anhydrous ethanol and acetone for 10 minutes each, and drying it at 60°C for 30 minutes.

8. The method for preparing an F-ZIF-8 / PVDF / FP multifunctional smart coating according to claim 1, characterized in that: The aluminum alloy substrate is 6061 aluminum alloy.

9. The F-ZIF-8 / PVDF / FP multifunctional smart coating prepared by the method of any one of claims 1-8, wherein the F-ZIF-8 / PVDF / FP multifunctional smart coating comprises ZIF-8 nanoparticles with a regular octahedral shape and a micro-nano rough structure obtained by fluorinating ZIF-8 nanoparticles with PFDTES, PVDF forming a flexible bonding network, and Al 3+ The fluorescent probe is uniformly dispersed within it.

10. The application of the F-ZIF-8 / PVDF / FP multifunctional intelligent coating as described in claim 9 in aluminum alloy superhydrophobic coatings, anti-corrosion coatings, and in-situ identification and monitoring of corrosion.

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