Preparation method of ZnO composite structure bacteriostatic film
By combining electrochemical etching and ZnO colloid spin coating, ZnO composite structure antibacterial film was prepared, which solved the problems of complex preparation process of the existing aluminum alloy surface antibacterial film and poor antibacterial effect, and achieved long-term and excellent antibacterial effect on the surface of aluminum alloy.
Patent Information
- Application Number
- CN202510277407.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-10
- Publication Date
- 2025-06-10
AI Technical Summary
The preparation process of existing aluminum alloy surface antibacterial films is complex, with low antibacterial rate, short aging and poor stability, making it difficult to achieve long-term antibacterial effect.
The combination of electrochemical etching and ZnO colloid spin coating was used to prepare a ZnO composite structure antibacterial film. The specific steps include electrochemical treatment of the aluminum alloy to form a porous structure corrosion film layer, then spin-coated ZnO colloid, and heat treatment in a muffle furnace to form a bilayer structure of PCL@ZnO layer and ZnO layer.
It achieves long-lasting and excellent antibacterial effect on the surface of aluminum alloy, has long-lasting and efficient antibacterial properties, and is simple in technology, green and environmentally friendly, and is suitable for public places.
Smart Images
Figure CN120119249A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a preparation method of an antibacterial film, and particularly to a preparation method of a ZnO composite structure antibacterial film. Background Art
[0002] Aluminum alloys have characteristics such as low density, high strength, and good ductility, and are widely used in public fields such as engineering construction, food processing, and medical equipment. However, the aluminum alloy surface itself hardly has antibacterial properties, and bacteria and microorganisms can easily colonize on the surface of aluminum alloy products, threatening human health. In recent years, antibacterial films on the aluminum alloy surface have become the latest research hotspots. It is reported that researchers have prepared antibacterial films on the aluminum alloy surface through various methods, such as magnetron sputtering, micro-arc oxidation, plasma spraying, electrochemical deposition, etc. Although the antibacterial films on the aluminum alloy surface can play an antibacterial effect to a certain extent, there are also deficiencies, such as complex preparation processes, low antibacterial rates, short antibacterial time effects, and poor stability.
[0003] TiO 2 , ZnO, SiO 2 and other oxides. Under light of a specific wavelength, electrons will undergo transitions. Free electrons (e - ) are generated on the conduction band, and holes (h + ) are generated on the valence band. The holes (h + ) undergo oxidation reactions to activate oxygen and water to generate highly chemically active reactive oxygen species (ROS). ROS can effectively decompose the organic matter and other nutrients that make up bacteria, thereby killing bacteria. ZnO particles have good photocatalytic activity, biocompatibility, and broad-spectrum antibacterial properties. ZnO particles show good antibacterial performance against bacteria such as Escherichia coli, Staphylococcus aureus, and Salmonella. ZnO nanoparticles are one of the best inorganic antibacterial materials. Therefore, how to use ZnO to prepare antibacterial films to achieve the purpose of long-term antibacterial has become a technical problem to be solved urgently. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide a preparation method of a ZnO composite structure antibacterial film that has a persistent and efficient antibacterial effect, so as to maintain excellent long-term antibacterial performance.
[0005] To solve the above technical problem, the preparation method of the ZnO composite structure antibacterial film of the present invention includes the following steps:
[0006] (1) Perform degreasing and cleaning pretreatment on the aluminum alloy to obtain an aluminum alloy substrate with a clean and tidy surface;
[0007] (2) Electrochemically process the aluminum alloy pretreated in step (1) to obtain an electrochemically corroded film layer with a porous structure on the surface of the aluminum alloy substrate;
[0008] (3) Spin-coat ZnO colloid on the surface of the aluminum alloy electrochemically treated in step (2) to obtain an aluminum alloy with uniformly distributed ZnO colloid;
[0009] (4) Place the aluminum alloy spin-coated with ZnO colloid in step (3) into a muffle furnace for heat preservation treatment to obtain a ZnO composite structure antibacterial film.
[0010] In the said step (1), the method of the pretreatment is to polish the surface of the aluminum alloy with 1500# SiC sandpaper and then rinse it with alcohol.
[0011] In the said step (2), the electrochemical treatment uses an electrochemical etching solution, and the electrochemical etching solution is acetic acid solution with deionized water as the solvent.
[0012] The said electrochemical corrosion solution is 0.1 - 0.2 M acetic acid aqueous solution, the voltage is 100 V, and the time is 5 - 15 min.
[0013] The pore diameter of the said electrochemically corroded film layer is ~150 nm.
[0014] In the said step (3), a spin coater is used for spin coating. The rotation speed of the spin coater is 1500 - 2000 rpm, the number of spin coating times of the ZnO colloid is 3 - 7 times, 5 drops each time, 50 μL for each drop, and the interval between each time is 30 s.
[0015] In the said step (3), the preparation method of the said ZnO colloid is as follows: Add 12.4 g of zinc acetate to 50 - 60 ml of malonic acid, and stir magnetically until clear and uniform; Measure 8 - 10 mL of triethanolamine as a stabilizer, heat it to 65 - 75 °C and stir; Add triethanolamine to the solution in the above step and continuously stir at 65 - 75 °C for 1 - 2 h to obtain a clear and transparent ZnO colloid solution.
[0016] In the said step (4), the temperature of the heat treatment is 550 °C, the heat preservation time is 0.5 - 1 h, and after the heat preservation is completed, it is cooled to room temperature with the furnace.
[0017] The advantages of the present invention are:
[0018] It uses a method combining electrochemical etching and colloidal spin coating to prepare the ZnO composite structure antibacterial film. During the preparation process, the aluminum alloy is first electrochemically treated to prepare a porous corrosion film layer on the surface of the aluminum alloy by means of electrochemical treatment. Subsequently, ZnO colloidal spin coating treatment is carried out to deposit ZnO nano antibacterial agents on the surface of the porous film. Finally, heat treatment is carried out to prepare an antibacterial film composed of a PCL@ZnO layer and a ZnO layer. In particular, through the above specific method, a porous corrosion layer carrier is prepared by electrochemical corrosion before colloidal spin coating. The porous electrochemical corrosion film layer (PCL) can serve as a carrier for the growth of antibacterial agents, providing nucleation and growth sites for ZnO nanoparticles. The ZnO nano composite structure antibacterial film constructed by combining its electrochemical treatment and colloidal spin coating method has excellent long-term antibacterial performance. Therefore, this composite structure film has a persistent and efficient antibacterial effect. In addition, the constructed composite structure antibacterial film has the characteristics of simple process, environmental protection, etc., and can be widely used in public places such as shopping malls, supermarkets, and hospitals. Description of the Drawings
[0019] Figure 1 It is the surface SEM image of the aluminum alloy after electrochemical treatment in Example 2;
[0020] Figure 2 (a) is the surface SEM image of the traditional ZnO antibacterial film;
[0021] Figure 2 (b - d) are the surface SEM images of the composite structure ZnO antibacterial films prepared in Examples 1 - 3;
[0022] Figure 3 (a) is the cross-sectional SEM image and EDS data of the traditional ZnO antibacterial film;
[0023] Figure 3 (b) is the cross-sectional SEM image and EDS data of the composite structure ZnO film prepared in Example 2;
[0024] Figure 4 (a) is the surface SEM image after polishing for 5 minutes in Example 2;
[0025] Figure 4 (b) is the surface EDS data after polishing for 5 minutes in Example 2. Detailed Description of the Embodiments
[0026] The following further elaborates in detail on the preparation method of the ZnO composite structure antibacterial film of the present invention in conjunction with the drawings and specific embodiments.
[0027] Preparation method of ZnO composite structure antibacterial film of the present invention. First, an aluminum alloy is etched by an electrochemical etching technique to construct a porous structure corrosion film layer (PCL) on the surface of the aluminum alloy; then, ZnO colloid is spin-coated and heat-treated for insulation to obtain the composite structure antibacterial film; during the spin-coating process of the colloid, the ZnO colloid is evenly spread on the surface of the porous structure corrosion film layer (PCL). During the heat treatment process, the ZnO colloid nucleates and grows to form a double-layer structure with a PCL@ZnO layer and an outer ZnO film layer. This composite structure antibacterial film has long-lasting and excellent antibacterial effects. During daily use, even if the outermost ZnO film layer is worn and consumed, due to the presence of the PCL@ZnO layer, the surface of the aluminum alloy still has excellent antibacterial properties; this composite structure antibacterial film not only has a simple preparation process but also has excellent long-lasting antibacterial properties. The following verifies its effects through specific examples and comparative examples:
[0028] Example 1
[0029] The preparation method of the ZnO composite structure antibacterial film of the present invention includes the following steps:
[0030] (1) The aluminum alloy is polished with 1500# sandpaper to remove the oxide film, and after polishing, it is cleaned with alcohol;
[0031] (2) The aluminum alloy in step (1) is subjected to electrochemical etching treatment, and the specific parameters and steps are as follows: the electrochemical etching solution is 0.1M acetic acid aqueous solution, the voltage is 100V, and the time is 5min; after the electrochemical etching treatment, a porous structure alumina film (PCL) is obtained;
[0032] (3) The aluminum alloy after the electrochemical treatment in step (2) is placed on a spin coater, the rotation speed is set to 2000rpm, a ZnO colloid is dropped on the surface of the aluminum alloy using a pipette, the number of spin coating times is 3 times, 50μL is dropped each time, and the interval between each drop is 30s;
[0033] (4) The sample in step (3) is quickly placed in a muffle furnace at 550°C and kept warm for 0.5h. After 0.5h, it is cooled to room temperature with the furnace to obtain the composite structure antibacterial film.
[0034] (3) Spin-coat the ZnO colloid on the surface of the porous structure electrochemical corrosion film layer;
[0035] Example 2
[0036] (1) The aluminum alloy is polished with 1500# sandpaper to remove the oxide film, and after polishing, it is cleaned with alcohol;
[0037] (2) Electrochemically etch the aluminum alloy in step (1). The specific parameters and steps are as follows: The electrochemically etching solution is 0.15M acetic acid aqueous solution, the voltage is 100V, and the time is 10 min. After the electrochemical etching treatment, a porous structure alumina film (PCL) is obtained.
[0038] (3) Place the aluminum alloy after the electrochemical treatment in step (2) on a spin coater, set the rotation speed to 2000 rpm, use a pipette to drop ZnO colloid on the surface of the aluminum alloy, the number of spin coating times is 5 times, 50 μL is dropped each time, and the interval between each drop is 30 s.
[0039] (4) Quickly put the sample in step (3) into a muffle furnace at 550 °C and keep it warm for 1 h. After 1 h, cool it to room temperature with the furnace to obtain a composite structure antibacterial film.
[0040] Example 3
[0041] (1) Polish the aluminum alloy with 1500# sandpaper, and then clean it with alcohol after polishing.
[0042] (2) Electrochemically etch the aluminum alloy in step (1). The specific parameters and steps are as follows: The electrochemically etching solution is 0.2M acetic acid aqueous solution, the voltage is 100V, and the time is 15 min. After the electrochemical etching treatment, a porous structure alumina film (PCL) is obtained.
[0043] (3) Place the aluminum alloy after the electrochemical treatment in step (2) on a spin coater, set the rotation speed to 2000 rpm, use a pipette to drop ZnO colloid on the surface of the aluminum alloy, the number of spin coating times is 7 times, 50 μL is dropped each time, and the interval between each drop is 30 s.
[0044] (4) Quickly put the sample in step (3) into a muffle furnace at 550 °C and keep it warm for 1 h. After 1 h, cool it to room temperature with the furnace to obtain a composite structure antibacterial film.
[0045] Comparative Example 1
[0046] The preparation method of the traditional ZnO antibacterial film includes the following steps:
[0047] (1) Polish the aluminum alloy with 1500# sandpaper, and then clean it with alcohol after polishing.
[0048] (2) Place the aluminum alloy after the pretreatment in step (1) on a spin coater, set the rotation speed to 2000 rpm, use a pipette to drop ZnO colloid on the surface of the aluminum alloy, the number of spin coating times is 5 times, 50 μL is dropped each time, and the interval between each drop is 30 s.
[0049] (3) Rapidly place the sample in step (2) into a muffle furnace at 550 °C and keep it for 1 h. After 1 h, cool it to room temperature with the furnace to obtain a traditional ZnO antibacterial film.
[0050] Structural characterization
[0051] Characterize the microstructure of the aluminum alloy sample after the electrochemical etching treatment in Example 2. The SEM images are as Figure 1 shown. It can be seen from Figure 1 that after the aluminum alloy matrix in Example 2 is electrochemically corroded, there are a large number of pore structures on the surface of the aluminum alloy. After multiple measurements and calculations, the single pore is ~150 nm.
[0052] The surface SEM images of the ZnO antibacterial films prepared in Comparative Example 1 and Examples 1 - 3 are as Figure 2 shown.
[0053] It can be seen from Figure 2 (b - d) that the ZnO layers on the surfaces of the composite - structure antibacterial films prepared in Examples 1 - 3 are all in a wrinkled structure, mainly due to the difference in the thermal expansion coefficients between the ZnO film and the electrochemically corroded film layer (PCL). In addition, with the increase in the number of spin - coating times, the content of surface Zn elements gradually increases.
[0054] It can be seen from Figure 2 (a) that ZnO layers can also be formed on the surfaces of the samples prepared in Comparative Example 1, but the wrinkled structure is not obvious. At the same time, there are obvious defects such as cracks in the ZnO layer, and the Zn content is significantly lower than that in Examples 1 - 3.
[0055] It can be seen from Figure 3 (a) that the cross - section of the sample prepared in Comparative Example 1 is a single - layer ZnO layer; after measurement, the average thickness of this layer is 1.9 μm; the uniformity of the ZnO film prepared in Comparative Example 1 is poor, and there are defects such as pores in the film.
[0056] It can be seen from Figure 3 (b) that the cross - section of the sample prepared in Example 2 is a double - layer structure of an intermediate PCL@ZnO layer and an outermost ZnO layer. After measurement, the average thickness of the PCL@ZnO layer is 4.1 μm, and the average thickness of the outermost ZnO layer is 0.8 μm; the PCL@ZnO layer and the outermost ZnO layer of the sample prepared in Example 2 are uniform and dense, without obvious defects.
[0057] Polish the samples prepared in Example 2 and Comparative Example 1 on a polishing machine. The polishing material is a cashmere polishing cloth, the load is 5 N, and the polishing time is 5 min. As Figure 4(a) and 4(b), after polishing treatment, the outer ZnO layer gradually disappears, and the PCL@ZnO layer is exposed. In the PCL@ZnO layer, ZnO nanoparticles grow attached to the PCL layer, and the size of individual ZnO nanoparticles is about dozens of nanometers.
[0058] Antibacterial performance test
[0059] (1) General antibacterial performance test
[0060] According to the standard GB / T 21510-2008, the antibacterial performance of the samples prepared in Examples 1-3 and Comparative Example 1 was tested. Escherichia coli (CMCC(B)44102) and Staphylococcus aureus (CMCC(B)26003) were used as test strains. 100 μL of the bacterial solution (10 5 cfu / mL) was dropped on the surface of the sample and placed in a biochemical incubator at 37 °C for 1 hour, and the culture process was accompanied by ultraviolet lamp irradiation. After 1 hour, the sample was rinsed with 900 μL of sterile phosphate buffer solution (PBS). 100 μL of the washing solution was evenly dropped on the nutrient agar plate and spread evenly. At the same time, 100 μL of the washed bacterial solution was taken and diluted 10 -1 times, 10 -2 times, 10 -3 times, and then spread on the nutrient agar plate and counted respectively. The plate was placed in an incubator at 37 °C for 24 hours. Finally, the antibacterial rate of the sample was calculated from the remaining colony count in the agar plate, and the test results are shown in Table 1 below:
[0061] Table 1 Test results of the antibacterial performance of the film
[0062] Bacteriostatic rate (%) Comparative Example 1 Example 1 Example 2 Example 3 Escherichia coli 72.1 97.5 100 97.9 Staphylococcus aureus 76.3 94.2 100 95.0
[0063] Note: After testing, the antibacterial rate was 53.0% after the Escherichia coli bacterial solution (10 5 cfu / ml) was directly irradiated by the ultraviolet lamp for 1 hour; the antibacterial rate was 52.0% after the Staphylococcus aureus bacterial solution (10 5 cfu / ml) was directly irradiated by the ultraviolet lamp for 1 hour.
[0064] (2) Long-lasting antibacterial performance test
[0065] In accordance with the standard GB / T 21510-2008, the long-lasting antibacterial performance of the samples of Example 2 and Comparative Example 1 before and after polishing for 5 minutes was tested, and the results are shown in Tables 2 and 3.
[0066] Table 2 Test results of the long-lasting antibacterial performance of the film (Escherichia coli)
[0067] Bacteriostatic rate (%) Unpolished Polished for 5 min Example 2 100 95.4 Comparative Example 1 72.1 61.2
[0068] Note: After testing, when the Escherichia coli liquid with a concentration of 10 5 cfu / ml was directly irradiated by an ultraviolet lamp for 1 h, the antibacterial rate was 53.0%.
[0069] Table 3 Test results of the long-lasting antibacterial performance of the film (Staphylococcus aureus)
[0070] Bacteriostatic rate (%) Unpolished Polished for 5 min Example 2 100.0 95.0 Comparative Example 1 76.3 56.0
[0071] Note: After testing, when the Staphylococcus aureus liquid with a concentration of 10 5 cfu / ml was directly irradiated by an ultraviolet lamp for 1 h, the antibacterial rate was 52.0%.
[0072] After polishing for 5 min, due to the large consumption of ZnO on the surface of the sample prepared in Comparative Example 1, the antibacterial effect decreased significantly. The antibacterial rate against Escherichia coli decreased to 61.2%, and the antibacterial rate against Staphylococcus aureus decreased to 56.0%. The ZnO composite structure antibacterial film sample prepared in Example 2 still maintained excellent antibacterial properties after grinding and polishing for 5 minutes. The antibacterial rate against Escherichia coli was 95.4%, and the antibacterial rate against Staphylococcus aureus was 95.0%.
[0073] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by those skilled in the art within the scope of the essence of the present invention should also fall within the protection scope of the present invention.
Claims
1. A method for preparing a ZnO composite antibacterial film, comprising the following steps: (1) Degreasing and cleaning the aluminum alloy to obtain an aluminum alloy substrate with a clean and tidy surface; (2) electrochemically treating the aluminum alloy after the pretreatment in step (1) to obtain a porous electrochemical corrosion film layer (PCL) on the surface of the aluminum alloy substrate; (3) Spin coating the surface of the aluminum alloy after the electrochemical treatment in step (2) with ZnO colloid to obtain an aluminum alloy with uniform ZnO colloid distribution; (4) The aluminum alloy after spin coating of ZnO colloid in step (3) is placed in a muffle furnace for heat preservation treatment to obtain a ZnO composite structure antibacterial film.
2. The method for preparing the ZnO composite antibacterial film according to claim 1, characterized in that: In the step (1), the pretreatment method is to polish the surface of the aluminum alloy with 1500# SiC sandpaper and then rinse it with alcohol.
3. The method for preparing the ZnO composite antibacterial film according to claim 1, characterized in that: In the step (2), the electrochemical treatment uses an electrochemical etching solution, the electrochemical etching solution is an acetic acid solution, and the solvent is deionized water.
4. The method for preparing the ZnO composite antibacterial film according to claim 3, characterized in that: The electrochemical corrosion solution is a 0.1-0.2M acetic acid aqueous solution, the voltage is 100V, and the time is 5-15 minutes.
5. The method for preparing the ZnO composite antibacterial film according to claim 1, characterized in that: The pore size of the electrochemical corrosion film layer is ~150 nm.
6. The method for preparing the ZnO composite antibacterial film according to claim 1, characterized in that: In the step (3), a coating machine is used for spin coating, the rotation speed of the coating machine is 1500-2000 rpm, and the ZnO colloid is spun 3-7 times, 5 drops each time, 50 μL per drop, and 30 seconds interval between each drop.
7. The method for preparing the ZnO composite antibacterial film according to claim 1, characterized in that: In the step (3), the preparation method of the ZnO colloid is as follows: add 12.4g of zinc acetate to 50-60ml of malonic acid, and stir magnetically until the solution becomes clear and uniform; measure 8-10mL of triethanolamine as a stabilizer, heat to 75°C and stir; add triethanolamine to the solution of the above step and stir continuously at 65-75°C for 1-2h to obtain a clear and transparent ZnO colloid solution.
8. The method for preparing the ZnO composite antibacterial film according to claim 1, characterized in that: In the step (4), the heat treatment temperature is 550° C., the heat preservation time is 0.5 to 1 hour, and after the heat preservation is completed, the furnace is cooled to room temperature.