A method for preparing a nanocomposite structure and a nanocomposite structure

Abstract

This application relates to the field of nanomaterial preparation, and in particular to a method for preparing a nanocomposite structure and the nanocomposite structure itself. A method for preparing a nanocomposite structure includes the following steps: S1. Preparing a substrate; S2. Placing a metal mesh with a periodic mesh structure above the substrate, spaced at a predetermined distance from the substrate surface; S3. Performing plasma treatment on the substrate and the metal mesh; wherein the plasma treatment is performed simultaneously in a single process step: (a) bombarding the metal mesh to sputter and deposit its material onto the substrate surface, forming a deposition area; (b) directly bombarding the substrate surface to etch areas not effectively protected by the deposited material; through the synergistic effect of deposition and etching, a uniform nanoscale topological structure is formed on the substrate surface. This "single-step synchronous plasma treatment" preparation method simplifies the process, improves structural uniformity, and achieves excellent and stable surface properties.

Description

Technical Field

[0001] This application relates to the field of nanomaterial preparation technology, and in particular to a method for preparing a nanocomposite structure and the nanocomposite structure itself. Background Technology

[0002] In the fields of nanotechnology and materials science, functional surfaces with superhydrophobic or superhydrophilic properties have wide applications in oil-water separation, self-cleaning, and corrosion protection. Wettability primarily depends on the chemical composition and micro / nano geometry of the material surface. Currently, conventional methods for preparing superhydrophobic surfaces include chemical vapor deposition, sol-gel methods, and etching methods.

[0003] However, existing technologies still have significant drawbacks in practical applications: First, constructing uniform nanostructures with high aspect ratios on flexible or large-area substrates is quite challenging, often resulting in poor consistency in surface properties. Second, the bonding force between traditional nanocoatings and the substrate is weak; under harsh chemical environments such as strong acids, strong alkalis, or high-pressure erosion, the nanostructures are highly susceptible to oxidation, wear, or detachment, leading to rapid failure of hydrophobic properties. Furthermore, existing multi-step preparation processes typically involve complex chemical precursors, which are not only cumbersome and energy-intensive but also make it difficult to balance structural stability and the density of the chemical protective layer within the same process system.

[0004] Plasma technology, as a dry processing technique, is used for material surface cleaning, activation, and coating. However, traditional plasma treatments have limited capabilities in simultaneously constructing fine and uniform nanoscale physical structures. While plasma etching can physically / chemically bombard the substrate surface, the lack of external material deposition for protection results in an isotropic etching process, making it difficult to form high aspect ratio, periodically ordered nanostructures. This often leads to disordered surface morphology, uncontrollable roughness, and ultimately poor performance uniformity. Sputter deposition, on the other hand, requires switching equipment or conditions between multiple steps, which is not only cumbersome and prone to introducing contamination at the interface, but also results in weak mechanical bonding between the deposited layer and the substrate, making it susceptible to detachment under friction or chemical corrosion, leading to functional failure. Therefore, there is an urgent need for a simple, efficient method capable of fabricating uniform and durable nanostructures on a wide range of substrates over large areas. Summary of the Invention

[0005] To achieve a simple, efficient process that enables the fabrication of uniform and durable nanostructures on a wide range of substrates, this application provides a method for preparing nanocomposite structures and the nanocomposite structures themselves.

[0006] In a first aspect, this application provides a method for preparing a nanocomposite structure, employing the following technical solution: A method for preparing a nanocomposite structure includes the following steps: S1. Prepare the substrate; S2. Place a metal mesh with a periodic mesh structure above the substrate, and space it at a predetermined distance from the surface of the substrate; S3. Plasma treatment is performed on the substrate and the metal mesh; wherein... Plasma treatment is performed simultaneously in a single process step: (a) Bombarding a metal mesh to sputter and deposit its material onto the surface of the substrate, forming a deposition area; (b) Directly bombard the substrate surface to etch the areas that are not effectively protected by the deposited material; A uniform nanoscale topological structure is formed on the substrate surface through the synergistic effect of deposition and etching.

[0007] By employing the above technical solution, a metal mesh is used as both a "dynamic template" and a "material source." The dynamic template refers to the metal mesh acting as both a pattern template defining the deposition area on the substrate surface during plasma bombardment and continuously providing material source particles during the sputtering process. The pattern-defining effect of the template dynamically changes with the plasma treatment. Under the same plasma environment, the bombardment of the metal mesh (resulting in sputtering deposition) and the bombardment of the substrate (resulting in etching) are completely synchronized in time and compete with each other in space. This self-organized competitive process can directly "grow" a uniform nanostructure on the substrate surface in a single treatment, forming a hydrophilic nanostructure. Its advantages are: (1) Overcoming the drawbacks of simple etching: Simple etching can only form a shallow, disordered, rough structure because there is no metal atom replenishment. In the synergistic effect of this application, the deposition area forms an "in-situ mask" for the substrate, forcing the etching to concentrate on the area not protected by the deposition, thereby self-organizing to form a high aspect ratio, periodically regular nanograss array.

[0008] (2) Overcoming the drawbacks of simple deposition: Stepwise deposition results in a clear interface between the deposited layer and the substrate, weak bonding force, and poor wear resistance; while in the synchronous process of this application, the deposited atoms are embedded in the surface layer of the substrate being etched, forming a gradient transition layer like an "anchor bolt structure", which significantly enhances the bonding force, and the water contact angle remains at 155° after 10 rubs.

[0009] (3) Quantitative advantages of synergistic effect: The dynamic balance between deposition and etching not only constructs a uniform nano-topological structure, but also forms a robust interface integrating structure and material, thereby obtaining excellent and stable surface properties. This avoids the interface contamination, alignment error and thermal stress problems caused by multi-step processes, and significantly reduces equipment complexity, process time and energy consumption, providing a fundamental solution for realizing the manufacturing of large-area, low-cost and highly consistent nanostructures.

[0010] Furthermore, the preset distance is 0-10mm.

[0011] By employing the above technical solution, the distance between the metal mesh and the substrate is limited to the range of 0-10 mm. This distance range ensures that the particles sputtered from the metal mesh have a sufficiently short flight path and a moderate scattering angle. If the distance is too far (>10 mm), the particles will scatter severely, resulting in a blurred deposition pattern and making it difficult to form a clear, high aspect ratio nanostructure. The optimal range of 0-10 mm allows the deposited particles to be precisely "projected" onto the area below the corresponding mesh openings on the substrate, creating a sharp contrast with the etching process. This, in turn, synergistically produces a sharp, periodically regular nanostructure, ensuring the uniformity and repeatability of the final product's performance (such as contact angle).

[0012] Furthermore, the mesh spacing of the metal mesh is 10-500 μm; the material of the metal mesh is selected from at least one of Ti, Cu, Au, Ag, Cr, Pt, Fe and their alloys or oxides.

[0013] By employing the above technical solutions, limiting the mesh spacing (10-500 μm) essentially defines the macroscopic periodic template for the prepared nanostructure. This range ensures, on the one hand, that the structural units are small enough to achieve surface effects such as superhydrophobicity, and on the other hand, guarantees the mechanical stability and ease of processing of the template. Limiting the metal material controls the chemical composition and function of the nanostructure from the perspective of material source. For example, selecting Ti can form a TiO2 nanostructure with photocatalytic activity; selecting Cu or Ag can endow the structure with certain antibacterial properties; selecting inert metals (such as Au, Pt) or their oxides can ensure the chemical stability of the nanostructure under harsh environments. This provides a rich selection space for the functional design of the final product.

[0014] Furthermore, the material of the substrate is selected from at least one of plastics, fibers, glass, metals, ceramics, and carbon-based materials.

[0015] By employing the above-described technical solution, the underlying physical vapor deposition processes (sputter deposition and physical / chemical etching) are independent of the specific chemical activity of the substrate. This method can be applied to any material, whether it be a polymer (plastic, fiber), inorganic non-metallic material (glass, ceramic), conductor (metal), or carbon material, as long as its surface can be adequately etched under selected plasma conditions. This breaks through the stringent limitations imposed on substrates by traditional wet chemical methods or certain vapor deposition methods, enabling the direct fabrication of high-performance nanofunctional surfaces on flexible textiles, rigid glass, complex-shaped metal components, and even emerging carbon fiber / graphene devices, greatly expanding the industrial application scenarios of this technology.

[0016] Furthermore, the gas used in the plasma treatment in step S3 is selected from one or more of O2, Ar, N2 and H2.

[0017] By employing the above-mentioned technical solutions, limiting the selection of the plasma working gas is crucial for precisely controlling the surface chemical and physical morphology. O2 can be used for oxidative etching and to oxidize the deposit, forming a hydrophilic or photocatalytic surface; H2 or N2 can be used for reduction or nitriding. The inert gas Ar primarily generates physical sputtering, used for high-fidelity transfer of metal mesh patterns and the formation of clean metal nanostructures. By mixing different gases (such as Ar and O2), the chemistry of the etching and the composition of the deposit can be controlled independently and synchronously, thereby achieving synergistic optimization of the nanostructure morphology and surface chemical state, obtaining the target performance in a one-step process.

[0018] Furthermore, the plasma treatment process conditions in step S3 are: bias voltage -100V to -1000V, chamber pressure 1mTorr to 1000mTorr, and treatment time up to 5 hours.

[0019] By employing the above technical solution, the bias voltage (-100V to -1000V) determines the energy of the ions in the plasma. Too low an energy results in insufficient sputtering and etching rates, while too high an energy may cause lattice damage to the substrate or lead to over-etching and structural destruction. The pressure range (1-1000 mTorr) affects the mean free path of the particles and the plasma density, thereby controlling the uniformity of deposition and the anisotropy of etching. The time parameter (up to 5 hours), along with the above parameters, determines the final size (height, diameter) of the nanostructure. This optimized combination of parameters ensures that the competition between deposition and etching reaches a dynamic balance within a reasonable processing time, stably "growing" high aspect ratio and uniform nanostructures, avoiding performance defects caused by under-processing or over-processing.

[0020] Furthermore, it also includes step S4: removing the metal mesh and coating a functional film on the surface of the substrate on which the nanoscale topology is formed.

[0021] By adopting the above technical solution, a post-processing step is introduced to further improve and stabilize the performance of the final product. First, removing the metal mesh releases the substrate area that was previously obscured by the template and prevents the metal mesh from remaining as foreign matter and affecting product use. Second, coating with a hydrophobic functional film chemically modifies the constructed hydrophilic nanostructure, utilizing the synergistic effect of the low surface energy coating and the rough structure to transform the hydrophilic surface into a superhydrophobic surface.

[0022] Furthermore, the functional film is a hydrophobic film, and the hydrophobic film is selected from at least one of fluorocarbon film and organosilicon film.

[0023] By employing the above technical solutions, the selected fluorocarbon films (such as those based on CF bonds) or organosilicon films (such as those based on Si-O-Si bonds) possess extremely low surface energy. When these low surface energy materials are uniformly coated on a nanoscale rough structure, the contact area between water droplets and the solid surface can be minimized, thereby synergistically generating a strong "lotus effect." This not only endows the product with excellent self-cleaning, anti-fouling, and anti-adhesion properties, but the selected films also typically possess good adhesion, flexibility, and weather resistance, ensuring long-term stability of superhydrophobic properties, making them particularly suitable for applications in outdoor equipment, building coatings, and anti-icing fields.

[0024] Secondly, this application provides a nanocomposite structure, employing the following technical solution: A nanocomposite structure is prepared by any of the above preparation methods.

[0025] By employing the above technical solution, the resulting nanocomposite structure exhibits several advantages. First, its surface nanotopology is uniform, regular, and firmly bonded to the substrate. This is because it is "grown" in plasma through the redistribution of the substrate's own material and the embedding of foreign atoms, rather than simple adhesion. Second, the chemical composition of the structure (derived from the metal mesh) can be designed as needed. Finally, the structure demonstrates excellent and reliable surface properties, and because it is part of a holistic process rather than a fragile coating, it possesses superior resistance to abrasion, chemical corrosion, and long-term stability. This product can be used directly as a high-performance separation membrane, sensor, functional fabric, or protective coating.

[0026] In summary, this application has the following beneficial effects: This application utilizes a "single-step synchronous plasma treatment" preparation method, which brings significant and unexpected beneficial technical effects in simplifying the process, improving structural uniformity, obtaining excellent and stable surface properties (superhydrophobic, superhydrophilic, and corrosion resistant), and achieving efficient applications. Attached Figure Description

[0027] Figure 1 This is a process flow diagram for Example 1; Figure 2 A schematic diagram illustrating the operation of setting a preset distance (>0) between the metal mesh and the substrate surface; Figure 3 A schematic diagram illustrating the operation of setting the preset distance between the metal mesh and the substrate surface to 0; Figure 4 The left side (h=2mm) is the SEM image of Example 1, and the right side (h=0mm) is the SEM image of Example 3 (h=0mm). Figure 5 This is a diagram illustrating the evolution of the superhydrophobic surface preparation process in Example 1.

[0028] In the diagram, 1 is the substrate; 2 is the metal mesh; and 3 is the particle. Detailed Implementation

[0029] The present application will be further described in detail below with reference to the embodiments.

[0030] raw material It should be noted that: in the following examples, unless otherwise specified, the conditions shall be in accordance with conventional conditions or the manufacturer's recommended conditions; and the raw materials used in the following examples, unless otherwise specified, shall be from commercially available sources. The substrates are selected from polyethylene terephthalate (PET) film, polypropylene (PP) nonwoven fabric, and 304 stainless steel or 304 stainless steel sheet. The polyethylene terephthalate (PET) film has a thickness of 0.1mm or 0.2mm and can be purchased from suppliers such as Shantou Sanhui Plastic Products Co., Ltd. Before use, it should be ultrasonically cleaned with acetone, ethanol, and deionized water for 15 minutes each, and then dried with nitrogen. The polypropylene (PP) nonwoven fabric has a basis weight of approximately 50g / m² and is a commercially available product. Before use, it should be soaked in ethanol and ultrasonically cleaned for 30 minutes, then dried in a 60°C oven. Other materials that can be used include glass slides, silicon wafers, carbon fiber fabric, alumina ceramic sheets, and polytetrafluoroethylene (PTFE) sheets. Metal mesh (as a dynamic template and material source) can be made of copper or titanium. Copper mesh: Specification 1 (used in Examples 1 and 3): 200 mesh, theoretical mesh spacing approximately 75 micrometers (μm), wire diameter approximately 50 μm, purity 99.9%; available from, for example, Beijing Zhongjing Scientific Instruments Technology Co., Ltd.; Specification 2 (used in Example 3): 500 mesh, theoretical mesh spacing approximately 25 μm, wire diameter approximately 20 μm; Titanium mesh: Specification (used in Example 2): 100 mesh, theoretical mesh spacing approximately 150 μm, purity ≥99.6%; available from, for example, Baoji Titanium Industry Co., Ltd.; Silver mesh, stainless steel mesh (such as 316L), aluminum mesh, nickel mesh, etc., can also be used, with mesh spacing ranging from 10 μm to 500 μm. The plasma treatment gases all have a purity of ≥99.99% and can be controlled by standard gas cylinders and flow meters (MFC). Functional thin film precursor (for hydrophobic / hydrophilic modification), using 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FAS, C8F) 17C2H4Si(OCH2CH3)3 or tetraethyl orthosilicate (TEOS, Si(OCH2CH3)4); wherein FAS purity ≥97% is used to form fluorocarbon / organosilicon hybrid hydrophobic films by vapor deposition; TEOS is analytically pure and can be used to construct hydrophilic silica films by sol-gel method (not used in the examples, but provides an optional solution for hydrophilic functionalization); heptadecafluorodecyltrimethoxysilane (PFDS), octadecyltrichlorosilane (OTS) and other materials can also be selected for the preparation of different low surface energy hydrophobic films; Acetone and anhydrous ethanol: analytical grade, used for cleaning substrates; Hydrochloric acid and sodium hydroxide: analytical grade, used to prepare solutions with pH=2 and pH=12 for chemical stability testing; Diesel fuel and surfactants (such as Tween80): used to prepare oil-water emulsions for separation performance testing.

[0031] Example Example 1 Superhydrophobic nanocomposite structures were fabricated on PET films, referring to... Figure 1-3 The preparation method is as follows: S1. Clean the PET film, which serves as substrate 1; S2. Place the copper mesh 2 above the PET, with a 2mm gap; S3. Place the substrate in the ICP chamber, introduce an Ar / O2 mixed gas (80 / 20 sccm), pressure 50 mTorr, source power 500 W, bias voltage -400 V, and process for 60 minutes. This step simultaneously achieves: particle sputtering of the copper mesh under plasma bombardment, sputtering deposition of copper and oxidative etching of PET; a uniform nano-topological structure is formed on the substrate surface, and due to the introduction of oxygen-containing polar functional groups by plasma treatment, the surface exhibits hydrophilicity. S4. After removal, remove the copper mesh and place the sample in FAS vapor. Perform vapor deposition at 150°C for 1 hour to form a hydrophobic fluorosilicone film. SEM images of the obtained product are shown below. Figure 4 and Figure 5 ,in Figure 4 The left side of the middle section, h=2mm, corresponds to this embodiment.

[0032] Example 2 A superhydrophilic / underwater superoleophobic nanocomposite structure was prepared on PP nonwoven fabric. The preparation method is as follows: S1. Use PP non-woven fabric; S2. Place the titanium mesh on top of the nonwoven fabric, with a 5mm gap; S3. Introduce pure O2, pressure 100mTorr, source power 600W, bias voltage -300V, process for 60 minutes. This step simultaneously achieves: TiO2 deposition and intense oxidation etching of PP fibers. S4. Remove the titanium mesh and do not coat it with a hydrophobic film to directly obtain a superhydrophilic surface.

[0033] Example 3 A corrosion-resistant nanocomposite structure was prepared on stainless steel using the following method: S1. Grind and clean the 304 stainless steel sheet; S2. Place the copper mesh (500 mesh, 25μm opening) tightly against the stainless steel surface; S3.O2 / Ar mixed gas (O2 30 sccm, Ar 70 sccm), pressure 30 mTorr, source power 800W, bias voltage -600V, treatment for 60 minutes. This step simultaneously achieves: sputtering deposition of copper and oxidative etching of stainless steel; after treatment, the substrate surface becomes hydrophilic due to the introduction of oxygen-containing polar groups, forming a hydrophilic nano-substrate. S4. Remove the copper mesh, place the sample in FAS vapor, and perform vapor deposition at 150°C for 1 hour to form a hydrophobic fluorocarbon film on the hydrophilic nanostructure, obtaining a superhydrophobic surface. SEM images of the obtained product are shown below. Figure 4 ,in Figure 4 The right side of the middle section, h=0mm, corresponds to this embodiment.

[0034] Comparative Example Comparative Example 1 Nanocomposite structures were prepared on PET films using the following method: S1. Without placing a metal mesh on the PET substrate, etch for 60 minutes using only O2 plasma under the same conditions (-400V, 50mTorr); S2. After removal, replace the magnetron sputtering equipment and, under an argon atmosphere, uniformly deposit a copper film of about 30nm thick on the etched PET surface using a process with a power of 200W, a chamber pressure of 5mTorr, and a sputtering time of 15 minutes. S3. Perform FAS modification as in Example 1.

[0035] Comparative Example 2 Nanocomposite structures were prepared on PET films using the following method: S1. No metal mesh is placed on the PET substrate; S2. Process using the exact same plasma conditions as in Example 1 (Ar / O2, -400V, 60 minutes); S3. Perform FAS modification as in Example 1.

[0036] Comparative Example 3 Nanocomposite structures were prepared on PET films using the following method: Unlike Example 1, the distance between the metal mesh and the PET in Comparative Example 3 is 20 mm.

[0037] Comparative Example 4 Nanocomposite structures were prepared on PET films using the following method: Unlike Example 1, the plasma gas in Comparative Example 4 was pure Ar.

[0038] Performance testing The samples prepared in Examples 1-3 and Comparative Examples 1-4 were subjected to the following performance tests, and the test results are shown in Table 1.

[0039] 1. Surface morphology characterization The morphology, uniformity, and periodicity of the nanostructures on the sample surface were observed using a scanning electron microscope (SEM).

[0040] 2. Static contact angle measurement Using a contact angle meter, the static contact angle (CA) of a 5 μL droplet of deionized water or diesel fuel on the sample surface was measured at room temperature. At least 5 different locations were measured for each sample and the average value was taken. The water contact angle (WCA) of superhydrophobic surfaces was >150°, and the water contact angle of superhydrophilic surfaces was <5°.

[0041] 3. Durability Testing Abrasion resistance test: The sample surface was rubbed in a straight line with standard sandpaper (1000 mesh) under a load of 500g, with a friction distance of 10cm / cycle. The water contact angle was recorded after 10 cycles of friction.

[0042] Chemical stability test: The samples were immersed in solutions with pH=2 (hydrochloric acid solution) and pH=12 (sodium hydroxide solution) respectively, and allowed to stand at room temperature for 24 hours. After removal, they were rinsed with deionized water, dried with nitrogen, and their water contact angle was measured.

[0043] 4. Oil-water separation performance test (for Example 2) The prepared PP nonwoven fabric sample (5 cm in diameter) was fixed in a filter device. A 1 g / L diesel-water emulsion (containing 0.1 g / L Lween80 surfactant) was poured into the device for gravity-driven separation. The separation efficiency (η) was calculated using the following formula: η = (1 - C_f / C_0) × 100%, where C_0 and C_f are the oil concentrations in the aqueous phase before and after separation (measured by a UV spectrophotometer). The flux (F) was calculated using the following formula: F = V / (A × t), where V is the permeate volume, A is the effective membrane area, and t is the separation time.

[0044] 5. Corrosion resistance test (for Example 3) Using an electrochemical workstation, Tafel polarization curves were performed on the samples in a 3.5 wt% NaCl solution. The self-corrosion current density (i_corr) was obtained by curve extrapolation. Using untreated 304 stainless steel as a blank control, the percentage reduction in corrosion current density was calculated.

[0045] Table 1 Performance Test Results As shown in Table 1, after acid and alkali resistance tests, the water contact angle of Example 1 was still as high as 158° and 160°, respectively, while the performance of Comparative Examples 1 and 2 decreased significantly under the same test conditions.

[0046] Example 2 uses PP nonwoven flexible fiber substrate and focuses on testing the core performance of oil-water separation; tests for abrasion resistance, acid resistance, and alkali resistance were not conducted. Furthermore, in Example 2, the oil-water separation efficiency is >99.5%, and the separation flux is 2500 L·m³. -2 ·h -1 In Example 3, the corrosion current density decreased by 98%.

[0047] As shown in Table 1, Comparative Example 2 (etching only, without metal mesh) failed to form an effective nanostructure, with a water contact angle of only 120°; Comparative Example 1 (stepwise deposition) exhibited a disordered structure and weak bonding, with a water contact angle of 138° and poor wear resistance (115° after friction). In contrast, Example 1 (simultaneous deposition and etching) formed a uniform nano-grass array (approximately 250 nm in height, with regular periods), achieving a water contact angle as high as 162°, which remained at 155°, 158°, and 160° respectively after wear resistance, acid resistance, and alkali resistance tests. This set of comparative data directly demonstrates that only by placing deposition and etching in the same process step, utilizing their spatial competition and temporal synchronization, can the unity of structural order, interface robustness, and macroscopic performance uniformity be achieved. Single etching lacks a "template," and single deposition lacks "anchoring"; both are indispensable. This is precisely the core innovation and unexpected technical effect of the "single-step synchronous plasma processing" method of this application.

[0048] Combined with Table 1 Figure 5 It can be seen that, Figure 5 From left to right, the images show scanning electron microscope (SEM) images of different plasma treatment stages. The first image shows the surface morphology of the substrate before or in the early stages of treatment, with a relatively smooth surface. The second image shows the fine granular structure formed in the early stages of treatment. The third image shows the uniform nano-grass array that begins to form under the synergistic effect of deposition and etching. The fourth image shows the morphology of the nanostructure further grown and matured in the later stages of treatment. All four images were taken at the same magnification, with a scale bar of 1 μm, demonstrating the complete evolution process from a smooth surface to a nano-grass array structure.

[0049] Furthermore, based on Table 1, it can also be seen that: The criticality of process parameters: Comparative Example 3 (20mm interval) exceeded the preferred range of 0-10mm in this application, resulting in severe particle scattering, leading to structural blurring and performance degradation (WCA 145°), demonstrating the non-obviousness and importance of the preset distance parameter. Comparative Example 4 (pure Ar gas) lacked chemically reactive gases, making it unable to effectively etch the polymer substrate to form a three-dimensional nanotopology; only metallic copper particles could be deposited on the surface. After FAS modification, due to the lack of rough structure support, the water contact angle (WCA 130°) was significantly lower than that of the examples, demonstrating the key role of oxidizing gases in forming hydrophilic nanostructures and the necessity of the rough structure and low surface energy coating synergistically constructing a superhydrophobic surface.

[0050] Durability and stability: The samples of this application (Examples 1 and 3) still maintain excellent superhydrophobicity (WCA>150°) after abrasion and chemical corrosion resistance tests, indicating that the hydrophilic nanostructure constructed by the process of this application is firmly and synergistically stable with the hydrophobic film. This integrated structure-coating design gives the product excellent durability.

[0051] Outstanding application performance: The superhydrophilic nonwoven fabric prepared in Example 2 exhibits high efficiency and high throughput in oil-water separation applications, demonstrating the great potential of this application in solving practical environmental problems.

[0052] The above systematic performance comparison data fully demonstrates that the "single-step synchronous plasma treatment" preparation method provided in this application brings significant and unexpected beneficial technical effects in simplifying the process, improving structural uniformity, obtaining excellent and stable surface properties (superhydrophobic, superhydrophilic, and corrosion resistant), and achieving efficient applications.

[0053] The embodiments are merely illustrative of this application and are not intended to limit it. Those skilled in the art can make modifications to these embodiments without contributing any inventive step after reading this specification, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A method for preparing a nanocomposite structure, characterized in that, Includes the following steps: S1. Prepare the substrate; S2. Place a metal mesh with a periodic mesh structure above the substrate, and space it at a predetermined distance from the surface of the substrate; S3. Plasma treatment is performed on the substrate and the metal mesh; wherein... Plasma treatment is performed simultaneously in a single process step: (a) Bombarding a metal mesh to sputter and deposit its material onto the surface of the substrate, forming a deposition area; (b) Directly bombard the substrate surface to etch the areas that are not effectively protected by the deposited material; A uniform nanoscale topological structure is formed on the substrate surface through the synergistic effect of deposition and etching.

2. The method for preparing a nanocomposite structure according to claim 1, characterized in that, The preset distance is 0-10mm.

3. The method for preparing a nanocomposite structure according to claim 1, characterized in that, The mesh spacing of the metal mesh is 10-500μm; the material of the metal mesh is selected from at least one of Ti, Cu, Au, Ag, Cr, Pt, Fe and their alloys or oxides.

4. The method for preparing a nanocomposite structure according to claim 1, characterized in that, The material of the substrate is selected from at least one of plastics, fibers, glass, metals, ceramics and carbon-based materials.

5. The method for preparing a nanocomposite structure according to claim 1, characterized in that, The gas used in the plasma treatment in step S3 is selected from one or more of O2, Ar, N2 and H2.

6. The method for preparing a nanocomposite structure according to claim 1, characterized in that, The plasma treatment process conditions in step S3 are: bias voltage -100V to -1000V, chamber pressure 1mTorr to 1000mTorr, and treatment time up to 5 hours.

7. The method for preparing a nanocomposite structure according to claim 1, characterized in that, It also includes step S4: removing the metal mesh and coating a functional film on the surface of the substrate on which the nanoscale topology is formed.

8. The method for preparing a nanocomposite structure according to claim 7, characterized in that, The functional film is a hydrophobic film, and the hydrophobic film is selected from at least one of fluorocarbon film and organosilicon film.

9. A nanocomposite structure, characterized in that, The nanocomposite structure is prepared by the method described in any one of claims 1-8.

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