Plasma-based VOx / Au / PVA composite functional film, and preparation method and application thereof
The plasma-induced liquid-phase chemistry method was used to prepare VOx/Au/PVA composite films under mild conditions, which solved the dispersion and bonding problems of VOx/AuNP composite materials in traditional methods, and achieved improved material properties and multifunctional applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HENAN UNIVERSITY
- Filing Date
- 2026-04-30
- Publication Date
- 2026-06-12
Smart Images
Figure CN122188200A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of nanocomposite material preparation technology, and particularly relates to a method for preparing a composite functional material thin film. Background Technology
[0002] Vanadium oxide (VO) x ) is a class of widely used materials whose oxidation state can be tunable (V 2+ -V 5+ This allows for the formation of various stoichiometric phases (V₂O₃, VO₂, V₂O₅) with different functional properties. x The mixed valence states, structural flexibility, and strong electronic interactions of V₂ highlight its potential as an advanced multifunctional material in a wide range of applications. For example, VO₂ undergoes a reversible metal-insulator phase transition (MIT) at approximately 68°C, transforming from an insulating monoclinic phase to a metallic rutile phase. This phase transition, driven by strong electronic correlations, makes it applicable to fields such as smart windows, electronic and optical switches, and infrared sensors. On the other hand, V₂O₅ possesses a unique layered structure and exhibits high redox activity and excellent ionic conductivity, making it a highly promising candidate material for applications such as batteries, supercapacitors, gas sensors, and catalysts.
[0003] Traditional VO x Valence state control methods typically require high temperatures and strong reducing agents. These processes are not only energy-intensive but also introduce impurities, alter crystallinity, and compromise the material's functionality and structural integrity. Furthermore, maintaining the stability of the oxide phase while achieving valence state control remains a challenge, especially in applications requiring uniform and defect-free nanostructures. These limitations underscore the necessity of developing innovative and efficient processing strategies to precisely control valence state while preserving material purity and functionality. x The price state.
[0004] In recent years, gold nanoparticles (AuNPs), as a class of versatile functional nanomaterials, have attracted widespread attention in various technological applications due to their unique physicochemical properties. A significant characteristic of AuNPs is their localized surface plasmon resonance (LSPR) effect, which enables them to interact strongly with light, especially in the near-infrared region. This property allows AuNPs to convert near-infrared light into heat energy, offering significant advantages in photothermal therapy (e.g., cancer hyperthermia and bacterial clearance). Furthermore, AuNPs exhibit excellent catalytic activity, conductivity, and biocompatibility, further expanding their potential applications in biosensing, nanomedicine / drug delivery, and energy-related technologies.
[0005] AuNPs and vanadium oxide (VO) xThe combination of these two materials can fully utilize their unique properties and produce novel nanocomposite materials with enhanced functions, thus enabling their application in a wide range of fields. Traditional VO x Synthesis methods for / AuNP composite materials, such as high-temperature treatment or chemical reduction, typically require long reaction times, the use of reducing agents, and harsh reaction conditions, all of which can lead to the generation of unwanted byproducts and impurities. Furthermore, traditional multi-step processes involving "synthesizing nanoparticles first and then composite" struggle to achieve the desired results with gold nanoparticles and VOCs. x Uniform dispersion and tight interfacial bonding at the nanoscale limit further improvements in material properties. These limitations underscore the need to develop more efficient, flexible, and environmentally friendly VOCs. x The necessity of the synthesis method of / AuNP composite materials.
[0006] Therefore, it is necessary to develop a method for achieving VO under mild conditions. x A simple, efficient, and green preparation method for valence state regulation and in-situ generation of gold nanoparticles is of great significance for promoting the development of multifunctional nanocomposite materials. Summary of the Invention
[0007] To address the aforementioned technical problems, this invention proposes a plasma-based VO... x Au / PVA composite functional films, their preparation methods, and applications. This method enables the in-situ generation of gold nanoparticles and the regulation of vanadium oxide valence state under mild conditions, thereby obtaining multifunctional composite materials with uniform structure, good dispersion, and excellent performance.
[0008] To achieve the above objectives, the technical solution of the present invention is implemented as follows:
[0009] A plasma-based VO x The preparation method of Au / PVA composite functional thin film is as follows:
[0010] (1) Dissolve polyvinyl alcohol in deionized water and ultrasonically disperse it to form a homogeneous PVA solution;
[0011] (2) Add gold precursor solution and vanadium source solution to the PVA solution obtained in step (1), mix and stir evenly to obtain reaction precursor solution;
[0012] (3) The reaction precursor solution is treated under atmospheric pressure by plasma-induced liquid phase chemistry (PiLC) method, that is, by using a micro plasma device with needle-liquid discharge structure, so that the active species generated in the system drive the vanadium oxide to change from high valence state to low valence state, and simultaneously realize the in-situ generation of Au nanoparticles.
[0013] (4) The solution after step (3) is cast into a mold (e.g., poured into a petri dish) and dried to obtain VO. x / Au / PVA composite functional film, in which VO x The components are VO2, V2O3, and V2O5.
[0014] Furthermore, the concentration of the PVA solution in step (1) above is 0.5-2.0 wt%.
[0015] The gold precursor is selected from one or more of chloroauric acid (HAuCl4), gold chloride, and gold complexes; the vanadium source is selected from one or more of vanadium pentoxide (V2O5), ammonium metavanadate, and metavanadate.
[0016] In a further preferred embodiment, the gold precursor is chloroauric acid, and the vanadium source is vanadium pentoxide.
[0017] In the above-mentioned reaction precursor solution, the concentration of chloroauric acid is 0.05-0.4 mM, and the concentration of vanadium source is 0.05-0.4 mM.
[0018] The aforementioned plasma treatment device is a micro-plasma device with a needle-liquid discharge structure, including an anode, a cathode, a solution, a flow display, and a power supply; wherein the anode is a carbon rod electrode immersed in the solution, and the cathode is a stainless steel tube with an inner diameter of 200-300μm, which is placed vertically 0.5-2 mm above the surface of the mixed liquid.
[0019] Furthermore, in the above plasma treatment, an inert gas is used as the plasma working gas with a flow rate of 10-50 SCCM; a high-voltage power supply is used to drive the discharge with a voltage of 1-5 kV and a current of 2-10 mA; the plasma treatment time is 2-8 min, and the reaction solution is stirred during the treatment.
[0020] The drying temperature in step (4) above is room temperature or 40-60℃.
[0021] VO prepared using the above preparation method x / Au / PVA composite functional film. Among them, VO x AuNPs are uniformly loaded onto PVA, with the AuNPs having a particle size range of 10-45 nm; the thickness of the composite functional film is 3-8 μm.
[0022] The above VO x Applications of Au / PVA composite functional films in smart dimming materials, antibacterial coatings, or photothermal functional devices.
[0023] The beneficial effects of this invention are:
[0024] (1) This invention utilizes a one-step plasma-induced liquid-phase chemistry (PiLC) method, using polyvinyl alcohol aqueous solution as the reaction system. By introducing a gold precursor and a vanadium source, the valence state of vanadium oxide and the in-situ generation of gold nanoparticles are achieved under atmospheric pressure micro-plasma, avoiding the traditional multi-step process. Moreover, this process does not require external reducing agents or high-temperature treatment, and has the characteristics of simple process, low energy consumption and environmental friendliness.
[0025] (2) In the composite material prepared by the present invention, VO x Gold nanoparticles are uniformly dispersed in the PVA matrix with tight interfacial bonding. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterization revealed a uniform nanostructure distribution without significant agglomeration. The PVA matrix, acting as a dispersion and stabilizing medium, inhibits nanoparticle aggregation and provides excellent film-forming properties, resulting in a uniform, self-supporting thin film structure. These structural features enhance interfacial interactions and energy transfer efficiency, thereby improving the material's photothermal response and antibacterial properties, achieving synergistic enhancement of multifunctional performance, and further improving the material's structural stability.
[0026] (3) The composite functional film prepared by the present invention has both thermochromic properties and photothermal response capability, and exhibits good antibacterial properties. It can be applied to fields such as smart dimming materials, antibacterial coatings and photothermal functional devices.
[0027] (4) This method is applicable to aqueous systems and is easy to achieve thin film production and large-scale preparation. Attached Figure Description
[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0029] Figure 1 This is a schematic diagram of the microplasma device with a needle-liquid discharge structure used in this invention.
[0030] Figure 2 The images show scanning electron microscope (SEM) images of the surface morphology of the composite films obtained under different treatment conditions; where (a) is the V2O5 / PVA film prepared in Comparative Example 2; and (b) is the V2O5 / PVA film prepared in Comparative Example 1. x / PVA-10 min film; (c) VO prepared in Example 3 x / Au / PVA-10 min film; (d) VO prepared in Example 3 xHigh-magnification image of the / Au / PVA-10 min thin film.
[0031] Figure 3 The images show transmission electron microscopy (TEM) images of the composite material and their corresponding high-resolution lattice structure diagrams.
[0032] Figure 4 The results are shown in the X-ray photoelectron spectroscopy (XPS) analysis of the composite material; (a) is the high-resolution XPS spectrum of V2O5 / PVA (Comparative Example 2); (b) is the V2p spectrum of Comparative Example 1. x (c) High-resolution XPS spectrum of V 2p from PVA-10 min; (d) V 2p spectrum from Example 3. x (d) High-resolution XPS spectrum of V 2p in Example 3 (Au / PVA-10 min); x Au 4f high-resolution XPS spectrum of / Au / PVA-10 min.
[0033] Figure 5 This is a graph showing the optical transmittance of the composite thin film as a function of temperature.
[0034] Figure 6 The image shows the photothermal response curve of the composite film under near-infrared light irradiation.
[0035] Figure 7 The image shows the test results of the antibacterial properties of the composite film. Detailed Implementation
[0036] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0037] Example 1
[0038] This embodiment presents a plasma-based VO x The preparation method of Au / PVA composite functional thin film is as follows:
[0039] (1) Weigh a certain amount of polyvinyl alcohol (PVA) and dissolve it in deionized water. Treat it under ultrasonic conditions for 1 h to obtain a uniform PVA solution with a PVA mass fraction of 1.0 wt%.
[0040] (2) Add chloroauric acid (HAuCl4) solution and vanadium pentoxide (V2O5) solution to the PVA solution obtained in step (1) in sequence, so that the concentration of HAuCl4 is 0.1 mM and the concentration of V2O5 is 0.2 mM, and stir thoroughly to obtain a homogeneous reaction precursor solution.
[0041] (3) The precursor solution was treated using a micro-plasma device under the following conditions: the cathode was positioned approximately 1 mm above the liquid surface, the helium flow rate was 25 SCCM, the discharge voltage was 2 kV, the current was 5 mA, and the treatment time was 5 min. Stirring was performed during the treatment. The micro-plasma device is as follows: Figure 1 As shown, it includes an anode, a cathode, a solution, a flow indicator, and a power supply; the anode is a carbon rod electrode immersed in the solution, and the cathode is a stainless steel tube with an inner diameter of 250 μm.
[0042] (4) The treated solution was poured into a petri dish and allowed to dry naturally at room temperature to form a film, yielding VO x / Au / PVA composite functional film, also known as VO x An Au / PVA-5 μm composite functional film. The AuNPs have a particle size range of 10-45 nm; the composite functional film has a thickness of 5 μm.
[0043] Example 2
[0044] This embodiment presents a plasma-based VO x The preparation method of Au / PVA composite functional thin film is as follows:
[0045] (1) Weigh a certain amount of polyvinyl alcohol (PVA) and dissolve it in deionized water. Treat it under ultrasonic conditions for 1 h to obtain a uniform PVA solution with a PVA mass fraction of 1.0 wt%.
[0046] (2) Add chloroauric acid (HAuCl4) solution and vanadium pentoxide (V2O5) solution to the PVA solution obtained in step (1) in sequence, so that the concentration of HAuCl4 is 0.1 mM and the concentration of V2O5 is 0.2 mM, and stir thoroughly to obtain a homogeneous reaction precursor solution.
[0047] (3) The reaction precursor solution was treated using a micro-plasma device. The treatment conditions were: the cathode was placed about 1 mm above the liquid surface, the helium flow rate was 25 SCCM, the discharge voltage was 2 kV, the current was 5 mA, the treatment time was 8 min, and the solution was stirred during the treatment.
[0048] (4) The treated solution was poured into a petri dish and allowed to dry naturally at room temperature to form a film, yielding VO x / Au / PVA composite functional film, also known as VO x An Au / PVA-8 min composite functional film. The AuNPs have a particle size range of 10-45 nm; the composite functional film has a thickness of 5 μm.
[0049] Example 3
[0050] This embodiment presents a plasma-based VO x The preparation method of Au / PVA composite functional thin film is as follows:
[0051] (1) Weigh a certain amount of polyvinyl alcohol (PVA) and dissolve it in deionized water. Treat it under ultrasonic conditions for 1 h to obtain a uniform PVA solution with a PVA mass fraction of 1.0 wt%.
[0052] (2) Add chloroauric acid (HAuCl4) solution and vanadium pentoxide (V2O5) solution to the PVA solution obtained in step (1) in sequence, so that the concentration of HAuCl4 is 0.1 mM and the concentration of V2O5 is 0.2 mM, and stir thoroughly to obtain a homogeneous reaction precursor solution.
[0053] (3) The reaction precursor solution was treated using a micro-plasma device. The treatment conditions were as follows: the cathode was placed about 1 mm above the liquid surface, the helium flow rate was 25 SCCM, the discharge voltage was 2 kV, the current was 5 mA, the treatment time was 10 min, and the mixture was stirred during the treatment.
[0054] (4) The treated solution was poured into a petri dish and allowed to dry naturally at room temperature to form a film, yielding VO x / Au / PVA composite functional film, also known as VO x / Au / PVA-10 min composite functional film. The AuNPs have a particle size range of 10-45 nm; the thickness of the composite functional film is 5 μm.
[0055] Comparative Example 1
[0056] VO in this comparative example x The preparation method of the PVA composite functional film differs from that in Example 3 in that HAuCl4 is not added to the reaction precursor solution. The steps are as follows:
[0057] (1) Weigh a certain amount of polyvinyl alcohol (PVA) and dissolve it in deionized water. Treat it under ultrasonic conditions for 1 h to obtain a uniform PVA solution with a PVA mass fraction of 1.0 wt%.
[0058] (2) Add vanadium pentoxide (V2O5) solution to the PVA solution obtained in step (1) to make the V2O5 concentration 0.2mM, and stir thoroughly to obtain a homogeneous reaction precursor solution.
[0059] (3) The reaction precursor solution was treated using a micro-plasma device. The treatment conditions were as follows: the cathode was placed about 1 mm above the liquid surface, the helium flow rate was 25 SCCM, the discharge voltage was 2 kV, the current was 5 mA, the treatment time was 10 min, and the mixture was stirred during the treatment.
[0060] (4) The treated solution was poured into a petri dish and allowed to dry naturally at room temperature to form a film, yielding VO x / PVA-10min composite functional film. The thickness of the composite functional film is 5 μm.
[0061] Comparative Example 2
[0062] The preparation method of the V2O5 / PVA composite functional film in this comparative example differs from that in Example 3 in that the precursor solution does not contain HAuCl4 and is not subjected to plasma treatment. The steps are as follows:
[0063] (1) Weigh a certain amount of polyvinyl alcohol (PVA) and dissolve it in deionized water. Treat it under ultrasonic conditions for 1 h to obtain a uniform PVA solution with a PVA mass fraction of 1.0 wt%.
[0064] (2) Add vanadium pentoxide (V2O5) solution to the PVA solution obtained in step (1) to make the V2O5 concentration 0.2mM, and stir thoroughly to obtain a homogeneous reaction precursor solution.
[0065] (3) Pour the reaction precursor solution obtained in step (2) into a petri dish and allow it to dry naturally at room temperature to form a film, thereby obtaining a V2O5 / PVA composite functional film. The thickness of the composite functional film is 5 μm.
[0066] The untreated V2O5 / PVA film prepared in Comparative Example 2 ( Figure 2 In sample a), V₂O₅ is embedded in the polymer matrix as large aggregates. In contrast, the V₂O₅ sample treated with plasma-induced liquid-phase chemistry (PiLC) exhibits... x / PVA-10 min ( Figure 2 b) and VO x / Au / PVA-10 min ( Figure 2 c) shows a significant improvement in particle dispersibility. It is worth noting that... Figure 2 d showcases VO x High-magnification image of / Au / PVA-10 min, where VO xIt exhibits a uniformly dispersed, well-separated sheet-like structure. The research results show that PILC, as a more environmentally friendly technology, can achieve uniform dispersion of vanadium oxides without the need for harsh chemical additives or energy-intensive processes.
[0067] TEM images of the composite thin film prepared in this invention are as follows: Figure 3 As shown. This indicates that AuNPs are uniformly dispersed in VO. x around, Figure 3 The regions marked (a1) to (a4) correspond to the (113) crystal plane of V2O3, the (200) crystal plane of VO2, the (101) crystal plane of V2O5, and the (111) crystal plane of metallic Au, respectively.
[0068] like Figure 4 As shown, the valence state changes of vanadium in the material were analyzed using XPS. In the untreated V₂O₅ / PVA sample (Comparative Example 2), its V₂p spectrum (…) Figure 4 a) Mainly manifested as V 5+ The characteristic peaks indicate that vanadium exists in a high valence state.
[0069] After plasma-liquid phase treatment, the VO obtained in Comparative Example 1 x V 2p spectrum of the PVA-10 min sample ( Figure 4 b) Display V 5+ V 4+ and V 3+ The coexistence of multiple valence states indicates that some V values are present during the processing. 5+ Reduction occurs, forming a mixed valence state VO. x Structure. For example... Figure 4 As shown in c, in Example 3, VO x V was also observed in the / Au / PVA-10 min sample. 5+ V 4+ and V 3+ The coexistence characteristic further indicates that plasma treatment can achieve valence state modulation of vanadium oxides. Meanwhile, as... Figure 4 As shown in d, the characteristic peaks of metallic gold appear in the Au 4f spectrum, indicating that the gold precursor was reduced to form gold nanoparticles during the processing.
[0070] Based on the above results, it can be concluded that during plasma treatment, the active reducing species generated in the system participate in the reduction processes of both gold ions and vanadium oxides. Because gold ions have a stronger reducing tendency, they preferentially consume some of the reducing species, thus affecting the degree of reduction of vanadium oxides, ultimately forming VO₄²⁻ with multiple valence states. x structure.
[0071] Example 4
[0072] This embodiment presents a plasma-based VO x The preparation method of Au / PVA composite functional thin film is as follows:
[0073] (1) Weigh a certain amount of polyvinyl alcohol (PVA) and dissolve it in deionized water. Treat it under ultrasonic conditions for 1 h to obtain a uniform PVA solution with a PVA mass fraction of 1.0 wt%.
[0074] (2) Add chloroauric acid (HAuCl4) solution and vanadium pentoxide (V2O5) solution to the PVA solution obtained in step (1) in sequence, so that the concentration of HAuCl4 is 0.2 mM and the concentration of V2O5 is 0.2 mM, and stir thoroughly to obtain a homogeneous reaction precursor solution.
[0075] (3) The precursor solution was treated using a micro-plasma device under the following conditions: the cathode was positioned approximately 1 mm above the liquid surface, the helium flow rate was 25 SCCM, the discharge voltage was 2 kV, the current was 5 mA, and the treatment time was 5 min. Stirring was performed during the treatment. The micro-plasma device is as follows: Figure 1 As shown, it includes an anode, a cathode, a solution, a flow indicator, and a power supply; the anode is a carbon rod electrode immersed in the solution, and the cathode is a stainless steel tube with an inner diameter of 250 μm.
[0076] (4) The treated solution was poured into a petri dish and allowed to dry naturally at room temperature to form a film, yielding VO x An Au / PVA composite functional film. The AuNPs have a particle size range of 10-45 nm; the composite functional film has a thickness of 5 μm.
[0077] Example 5
[0078] This embodiment presents a plasma-based VO x The preparation method of Au / PVA composite functional thin film is as follows:
[0079] (1) Weigh a certain amount of polyvinyl alcohol (PVA) and dissolve it in deionized water. Treat it under ultrasonic conditions for 1 h to obtain a uniform PVA solution with a PVA mass fraction of 2.0 wt%.
[0080] (2) Add chloroauric acid (HAuCl4) solution and vanadium pentoxide (V2O5) solution to the PVA solution obtained in step (1) in sequence, so that the concentration of HAuCl4 is 0.4 mM and the concentration of V2O5 is 0.05 mM, and stir thoroughly to obtain a homogeneous reaction precursor solution.
[0081] (3) The reaction precursor solution was treated using a micro-plasma device. The treatment conditions were: the cathode was placed about 2 mm above the liquid surface, the helium flow rate was 50 SCCM, the discharge voltage was 1 kV, the current was 2 mA, the treatment time was 10 min, and the solution was stirred during the treatment.
[0082] (4) The treated solution was poured into a petri dish and allowed to dry naturally at 40°C to form a film, yielding VO x An Au / PVA composite functional film. The AuNPs have a particle size range of 10-45 nm; the composite functional film has a thickness of 3 μm.
[0083] Example 6
[0084] This embodiment presents a plasma-based VO x The preparation method of Au / PVA composite functional thin film is as follows:
[0085] (1) Weigh a certain amount of polyvinyl alcohol (PVA) and dissolve it in deionized water. Treat it under ultrasonic conditions for 1 h to obtain a uniform PVA solution with a PVA mass fraction of 0.05 wt%.
[0086] (2) Add chloroauric acid (HAuCl4) solution and vanadium pentoxide (V2O5) solution to the PVA solution obtained in step (1) in sequence, so that the concentration of HAuCl4 is 0.05 mM and the concentration of V2O5 is 0.4 mM, and stir thoroughly to obtain a homogeneous reaction precursor solution.
[0087] (3) The reaction precursor solution was treated using a micro-plasma device. The treatment conditions were as follows: the cathode was placed about 0.5 mm above the liquid surface, the helium flow rate was 10 SCCM, the discharge voltage was 5 kV, the current was 10 mA, the treatment time was 5 min, and the solution was stirred during the treatment.
[0088] (4) The treated solution was poured into a petri dish and allowed to dry naturally at 60°C to form a film, yielding VO x An Au / PVA composite functional film. The AuNPs have a particle size range of 10-45 nm; the composite functional film has a thickness of 8 μm.
[0089] Implementation Results Example
[0090] The optical properties of the composite films prepared in Example 3, Comparative Example 1, and Comparative Example 2 were tested, and the results are as follows: Figure 5 As shown. VO processed by PiLC x / PVA-10 min and VO xThe transmittance of the / Au / PVA films decreased significantly with temperatures of 10 min, with modulation depths (ΔT) of 2.8% and 3.4%, respectively. This decrease in near-infrared transmittance with increasing temperature is consistent with the known thermochromic behavior of VO2, which is driven by the electron-structure coupling transition from a low-temperature monoclinic insulating phase to a high-temperature rutile metallic phase.
[0091] Figure 6 The image shows the photothermal response curve of the composite film under near-infrared light irradiation. Figure 6 a demonstrates V2O5 / PVA (Comparative Example 2), VO x / PVA-10 min (Comparative Example 1) and VO x Temperature curves of the / Au / PVA film under irradiation with different near-infrared laser powers (Example 3) after 10 min. x The temperature of the / Au / PVA film increased significantly and rapidly after 10 min at a power of 12 W (power density approximately 0.96 W / cm³). 2 After irradiation for 2 minutes, the temperature reached approximately 48°C at a power of 16 W (power density approximately 1.27 W / cm³). 2 After 2 minutes of irradiation, the temperature exceeded 55°C. In comparison, V2O5 / PVA and VO x The temperature rise of the PVA-10 min film is negligible. Figure 6 b shows that under 12 W near-infrared light irradiation, VO x The / Au / PVA-10 min film reached 48°C within 60 seconds and then maintained a stable temperature (48-55°C is the effective temperature range for killing bacteria). This rapid heating is attributed to the localized surface plasmon resonance (LSPR) of the gold nanoparticles, where incident near-infrared light excited the collective oscillation of conductive electrons on the surface of the gold nanoparticles.
[0092] The antibacterial properties of the composite films prepared in Example 3, Comparative Example 1, and Comparative Example 2 were evaluated using conventional methods. Figure 7 As shown, the composite film exhibits significant inhibitory effects on bacteria, with enhanced antibacterial efficacy under light irradiation. The composite film demonstrates stable antibacterial properties against both *Escherichia coli* and *Staphylococcus aureus*, and its antibacterial activity strongly depends on near-infrared light irradiation. After short-term near-infrared light irradiation (2 minutes), the V2O5 / PVA and V2O5 / PVA / V ... x / PVA-10 min film remains essentially inactive, while VO x The / Au / PVA-10 min film exhibited measurable antibacterial effect (~20%, p<0.01) after 2 minutes of irradiation. With prolonged irradiation time (10 minutes), VO... xThe antibacterial efficiency of / Au / PVA-10min was significantly improved, with antibacterial rates approaching 90% against both strains.
[0093] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A plasma-based VO x The method for preparing Au / PVA composite functional thin films is characterized by, The steps are as follows: (1) Dissolve polyvinyl alcohol in deionized water to form a PVA solution; (2) Add gold precursor solution and vanadium source solution to the PVA solution obtained in step (1), mix well, and obtain reaction precursor solution; (3) The reaction precursor solution obtained in step (2) is subjected to plasma treatment at room temperature and pressure; (4) The solution after step (3) is cast and dried to obtain VO x / Au / PVA composite functional film.
2. The plasma-based VO according to claim 1 x The method for preparing Au / PVA composite functional thin films is characterized by, The concentration of the PVA solution in step (1) is 0.5-2.0 wt%.
3. The plasma-based VO according to claim 1 x The method for preparing Au / PVA composite functional thin films is characterized by, In step (2), the gold precursor is selected from one or more of chloroauric acid, gold chloride and gold complex; the vanadium source is selected from one or more of vanadium pentoxide, ammonium metavanadate and metavanadate.
4. The plasma-based VO according to claim 3 x The method for preparing Au / PVA composite functional thin films is characterized by, The concentration of the gold precursor in the reaction precursor solution is 0.05-0.4 mM.
5. The plasma-based VO according to claim 3 x The method for preparing Au / PVA composite functional thin films is characterized by, The concentration of the vanadium source in the reaction precursor solution is 0.05-0.4 mM.
6. The plasma-based VO according to claim 5 x The method for preparing Au / PVA composite functional thin films is characterized by, The plasma treatment device is a micro-plasma device with a needle-liquid discharge structure, including an anode, a cathode, a solution, a flow display and a power supply; wherein the anode is a carbon rod electrode immersed in the solution, and the cathode is a stainless steel tube with an inner diameter of 200-300μm, which is placed vertically 0.5-2 mm above the surface of the mixed liquid.
7. The plasma-based VO according to claim 6 x The method for preparing Au / PVA composite functional thin films is characterized by, In the plasma treatment, an inert gas is used as the working gas for the plasma, with a gas flow rate of 10-50 SCCM; a high-voltage power supply is used to drive the discharge, with a voltage of 1-5 kV and a current of 2-10 mA; and the plasma treatment time is 2-8 min.
8. The plasma-based VO according to claim 5 x The method for preparing Au / PVA composite functional thin films is characterized by, The drying process is performed at room temperature or 40-60°C.
9. VO prepared by the preparation method according to any one of claims 1-8 x / Au / PVA composite functional film.
10. The VO according to claim 9 x Applications of Au / PVA composite functional films in smart dimming materials, antibacterial coatings, or photothermal functional devices.