Magnetically-driven micro-nano robot based on photocatalysis, preparation method and application of magnetically-driven micro-nano robot
By loading spinel-type ferrite magnetic nanoparticles on the surface of bismuth oxyhalide, a magnetically driven micro-nano robot is formed, which solves the problem of limited light absorption range of photocatalytic materials and fast carrier recombination rate, and achieves efficient photocatalytic sterilization effect.
Patent Information
- Application Number
- CN202510308735.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-17
- Publication Date
- 2025-06-27
AI Technical Summary
Existing photocatalytic materials such as bismuth oxyhalide have problems such as limited light absorption range and fast photogenerated carrier recombination rate, which is difficult to effectively solve the problem of bacterial drug resistance.
By loading spinel-type ferrite magnetic nanoparticles on the surface of bismuth oxyhalide, a magnetically driven micro-nano robot based on photocatalysis is formed, which effectively inhibits photogenerated carrier recombination, broadens the light absorption range, enhances the light absorption intensity, and has motion properties under the action of a magnetic field.
It has achieved important applications in the field of antibacterials, has excellent bactericidal effect, and can efficiently kill pathogens under the action of light and magnetic fields, including Mycobacterium tuberculosis, Staphylococcus, Salmonella, E. coli and Anthrax.
Smart Images
Figure CN120205178A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a magnetically driven micro-nanorobot based on photocatalysis, a preparation method thereof, and an application thereof, belonging to the technical field of material chemistry. Background Art
[0002] In the past few hundred years, bacterial infections have become one of the major problems threatening human health, causing tens of thousands of deaths every year. Among them, pathogenic bacteria such as Mycobacterium tuberculosis, Staphylococcus aureus, Salmonella, Escherichia coli, and Bacillus anthracis are particularly prominent. Although antibiotics have played an important role in combating bacterial infections, the problem of bacterial drug resistance caused by their long-term use has become increasingly serious, and even "super bacteria" with multiple drug resistances have emerged. Facing this severe challenge, the development of new antibacterial materials and technologies has become an urgent task.
[0003] As an emerging material technology, micro-nanorobots can reach microscopic regions that are difficult to reach by traditional materials due to their small size and controllable motion characteristics, and show great application potential in the fields of biomedical detection and environmental governance. Such materials can generate mechanical motion under the stimulation of external fields (such as magnetic fields, sound fields, and light fields), and among them, magnetically driven micro-nanorobots have attracted much attention due to their precise manipulation performance. Especially when combined with photocatalytic materials, such robots are expected to exhibit excellent antibacterial properties. Micro-nanorobots with light-responsive characteristics can be excited by light of a specific wavelength during the photocatalytic process to generate reactive oxygen species, thereby effectively killing various pathogenic microorganisms.
[0004] Based on the above background, the development of a magnetically driven micro-nanorobot combined with photocatalysis technology is of great significance for solving the problem of bacterial drug resistance. Among many photocatalytic materials, bismuth oxyhalide has attracted much attention due to its unique layered structure and excellent light absorption performance. Among them, bismuth oxyiodide (BiOI) has become a research hotspot due to its relatively narrow bandgap. However, single-component bismuth oxyhalide has problems such as limited light absorption range and fast recombination rate of photo-generated carriers. Therefore, it is particularly important to functionalize and modify bismuth oxyhalide. Summary of the Invention
[0005] In view of this, the purpose of the present invention is to provide a magnetically driven micro-nanorobot based on photocatalysis, a preparation method thereof, and an application thereof. The present invention uses bismuth oxyhalide as a carrier, and loads magnetic nanoparticles on its surface to form a bismuth oxyhalide micro-nanorobot based on photocatalysis. By effectively inhibiting the recombination of photo-generated carriers, broadening the light absorption range, enhancing the light absorption intensity, and improving the contact efficiency with pathogenic bacteria, this magnetically driven micro-nanorobot shows important application value in the antibacterial field.
[0006] To achieve the above purpose, the technical solution of the present invention is as follows.
[0007] A magnetic-driven micro-nano robot based on photocatalysis uses bismuth oxyhalide as a carrier, and spinel-type ferrite magnetic nanoparticles are loaded on the surface of the carrier. The molecular formula of the spinel-type ferrite is MFe2O4, where M is a divalent metal ion. The bismuth oxyhalide is BiOI with a flower-like structure, and the molar ratio of the carrier to the magnetic nanoparticles is 1:0.25 to 1.
[0008] Preferably, the flower-like structure is composed of BiOI nanosheets.
[0009] Preferably, the molar ratio of the carrier to the magnetic nanoparticles is 1:0.4 to 0.7.
[0010] Preferably, the M element is Fe, Mn, Co, Ni, Cu or Zn; the spinel-type ferrite magnetic nanoparticles are Fe3O4, MnFe2O4, CoFe2O4, NiFe2O4, CuFe2O4 or ZnFe2O4; more preferably, the spinel-type ferrite magnetic nanoparticles are MnFe2O4.
[0011] Preferably, the particle size of the spinel-type ferrite magnetic nanoparticles is 50 to 1000 nm.
[0012] A preparation method of the magnetic-driven micro-nano robot based on photocatalysis according to the present invention, the method steps include:
[0013] (1) Prepare spinel-type ferrite magnetic nanoparticles;
[0014] (2) Add the spinel-type ferrite magnetic nanoparticles into a KI solution, ultrasonically disperse them evenly, add an ethylene glycol solution of bismuth nitrate under mechanical stirring, stir for 4 to 8 h, then centrifuge to collect the solid, wash and dry to obtain a magnetic-driven micro-nano robot based on photocatalysis.
[0015] Preferably, in step (1), the iron source and the M source are mixed and dissolved to obtain a precursor solution; ammonia water is added dropwise to obtain a suspension; the precipitate is collected by centrifugation, the pH is adjusted to 9 to 11 with a NaOH solution, then placed in a hydrothermal reaction kettle, and reacted at 120 to 180 °C for 12 to 24 h, and naturally cooled, washed and dried to obtain spinel-type ferrite magnetic nanoparticles.
[0016] Preferably, the iron source and M source include one or more of chlorides, sulfates, nitrates, and acetates of the corresponding metal elements. For example, the iron source includes FeCl2·4H2O, FeSO4·7H2O, Fe(NO3)3·9H2O; the manganese source includes MnCl2·4H2O, MnSO4·4H2O, Mn(NO3)2·4H2O; the cobalt source includes CoCl2·6H2O, CoSO4·7H2O, Co(NO3)2·6H2O; the nickel source includes NiCl2, NiSO4·7H2O, Ni(NO3)2·6H2O; the copper source includes CuSO4·5H2O, Cu(CH3COO)2·H2O; the zinc source includes ZnSO4·7H2O, Zn(NO3)2·6H2O, Zn(CH3COO)2·2H2O.
[0017] Preferably, in step (2), the molar ratio of the spinel ferrite magnetic nanoparticles to KI is 0.25 - 1:1; more preferably 0.4 - 0.7:1; the molar ratio of KI to bismuth nitrate is 1 - 5:1.
[0018] An application of the magnetic - driven micro - nano robot based on photocatalysis according to the present invention, wherein the magnetic - driven micro - nano robot is used as a photocatalytic broad - spectrum bactericide.
[0019] Preferably, the magnetic - driven micro - nano robot is added to the solution of pathogenic bacteria to be killed, and sterilization is achieved under light irradiation and an external magnetic field.
[0020] Preferably, the pathogenic bacteria include Mycobacterium tuberculosis, Staphylococcus, Salmonella, Escherichia coli, and Bacillus anthracis.
[0021] Preferably, the light absorption range of the magnetic - driven micro - nano robot is 200 - 1000 nm; the light sources include sunlight, LED lights, and xenon lamps. The working magnetic field environment can be provided by any magnetic device.
[0022] Beneficial effects
[0023] The present invention provides a magnetic - driven micro - nano robot based on photocatalysis. Using bismuth oxyhalide as a carrier, magnetic nanoparticles are loaded on its surface to form a photocatalytic bismuth oxyhalide micro - nano robot, which effectively inhibits the recombination of photo - generated carriers, broadens the light absorption range, and enhances the light absorption intensity; meanwhile, it has a motion property under the action of a magnetic field.
[0024] The present invention provides a preparation method of a magnetic - driven micro - nano robot based on photocatalysis, which in - situ loads magnetic nanoparticles during the synthesis process of BiOI by a simple co - chemical bath method under normal temperature and pressure.
[0025] The present invention provides an application of a magnetically driven micro-nano robot based on photocatalysis, whose light absorption range covers the ultraviolet, visible light, and near-infrared regions. The magnetic driving properties imparted by the magnetic field enable the micro-nano robot to reach the microenvironment and achieve the purpose of sterilization under light. Magnetism is also of great benefit to the recycling of materials. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 This is an XRD diagram of the magnetically driven micro-nano robot provided in Example 1 of the present invention, which is composed of MnFe2O4 and BiOI in different molar ratios.
[0027] Figure 2 The morphology and element distribution diagram of the magnetically driven micro-nano robot BM-0.5 provided in Example 1 of the present invention.
[0028] Figure 3 This is a magnetic proof diagram of the magnetically driven micro-nano robot provided in Example 1 of the present invention under the action of a magnetic field in an aqueous solution.
[0029] Figure 4 This is a diagram showing the antibacterial effect of the magnetically driven micro-nano robot provided in Example 1 of the present invention.
[0030] Figure 5 The comparative results of the sterilization efficiency of the magnetically driven micro-nano robot in aqueous solution under the action of a magnetic field are provided in Example 1 of the present invention. DETAILED DESCRIPTION
[0031] The present invention is further described in detail below in conjunction with specific embodiments.
[0032] Example 1
[0033] (1) Magnetic iron oxide spinel nanoparticles were prepared by hydrothermal method. Weigh 0.02 mol of FeCl3·6H2O and 0.01 mol of MnCl2·4H2O compounds and add them to deionized water for ultrasonic dispersion and dissolution. Add a certain amount of NH3·H2O solution to form a suspension and centrifuge at 8000 rpm for 5 min. Then add 60 mL of a solution containing 15 g of NaOH to the precipitate. Place the suspension in a 100 mL polytetrafluoroethylene reactor and react at 180°C for 18 h. Use a magnet to absorb the product MnFe2O4, wash it with ethanol and water three times respectively, and then dry and grind it.
[0034] (2) The magnetic-driven bismuth oxyiodide micro-nanorobots were prepared by the co-chemical bath method. 3 mmol of KI was dissolved in 40 mL of deionized water to form a KI solution. MnFe2O4 was added to the KI solution at optimized molar ratios of 1:1, 0.5:1, and 0.25:1, respectively, to form solution a. 3 mmol of Bi(NO3)3·5H2O was dissolved in 10 mL of ethylene glycol to prepare solution b. Under mechanical stirring, solution b was gradually added dropwise into solution a and continuously stirred for 6 h. The obtained precipitate was washed three times with ethanol and deionized water and then dried in an oven at 80 °C. The synthesized magnetic-driven bismuth oxyiodide micro-nanorobots are denoted as BM-1, BM-0.5, and BM-0.25.
[0035] Figure 1 The XRD patterns of BiOI / MnFe2O4 micro-nanorobots with three different molar ratios are shown. The samples are the target phases and do not contain impurity phases. Figure 2 The morphology and elemental distribution maps of the optimized micro-nanorobot BM-0.5 are shown. Magnetic nanoparticles are in-situ loaded on BiOI nanoflowers. Figure 3 Pictures of the magnetic-driven bismuth oxyiodide micro-nanorobots under the action of a magnetic field are shown.
[0036] (3) Before the antibacterial experiment, instruments such as beakers, pipettes, and spreaders used were sterilized by ultraviolet light for 30 min. The pathogenic bacteria solution (10 8 CFU / mL) was placed in a 100 mL beaker, and then the magnetic-driven micro-nanorobots formed by loading BiOI with MnFe2O4 obtained in 1-2 were placed in the pathogenic bacteria solution. The sterilization experiment was carried out for 1 h under dark field and light field conditions, respectively.
[0037] Different sterilization effects were achieved by controlling the movement of the micro-nanorobots and the light and dark fields. The antibacterial effect diagram is as Figure 4 shown. Under magnetic drive and simulated sunlight by a xenon lamp (300 W), the sterilization effect of the BM-0.5 sample for 1 h can reach 99%.
[0038] The sterilization efficiency of magnetic-driven micro-nanorobots with different molar ratios under the same light conditions is as Figure 5 shown.
[0039] Example 2
[0040] In this example, the selected magnetic nanoparticles were Fe3O4, and the rest was the same as in Example 1.
[0041] (1) Prepare magnetic ferrite spinel nanoparticles by hydrothermal method. Weigh 0.03 mol of FeCl3·6H2O compound and add it to deionized water for ultrasonic dispersion and dissolution. Add a certain amount of NH3·H2O solution to form a suspension, then centrifuge at a speed of 8000 revolutions per minute for 5 minutes. Then add 60 mL of a solution containing 15 g of NaOH to the precipitate. Place the suspension in the inner lining of a 100 mL polytetrafluoroethylene reaction kettle, and then react at 180 °C for 18 h. Use a magnet to attract the product Fe3O4, wash it 3 times with ethanol and water respectively, and then dry and grind to obtain.
[0042] After testing, the final product is BiOI / Fe3O4, and the magnetic nanoparticles are in-situ loaded on the BiOI nanoflowers. Under magnetic drive and simulated sunlight by a xenon lamp (300 W), the magnetic-driven micro-nano robot has excellent bactericidal effects.
[0043] Example 3
[0044] The magnetic nanoparticles selected in this example are CoFe2O4, and the rest are the same as in Example 1.
[0045] (1) Prepare magnetic ferrite spinel nanoparticles by hydrothermal method. Weigh 0.02 mol of FeCl3·6H2O and 0.01 mol of Co(NO3)2·6H2O compounds and add them to deionized water for ultrasonic dispersion and dissolution. Add a certain amount of NH3·H2O solution to form a suspension, then centrifuge at a speed of 8000 revolutions per minute for 5 minutes. Then add 60 mL of a solution containing 15 g of NaOH to the precipitate. Place the suspension in the inner lining of a 100 mL polytetrafluoroethylene reaction kettle, and then react at 180 °C for 18 h. Use a magnet to attract the product CoFe2O4, wash it 3 times with ethanol and water respectively, and then dry and grind.
[0046] After testing, the final product is BiOI / CoFe2O4, and the magnetic nanoparticles are in-situ loaded on the BiOI nanoflowers. Under magnetic drive and simulated sunlight by a xenon lamp (300 W), the magnetic-driven micro-nano robot has excellent bactericidal effects.
[0047] Example 4
[0048] The magnetic nanoparticles selected in this example are NiFe2O4, and the rest are the same as in Example 1.
[0049] (1) Prepare magnetic ferrite spinel nanoparticles by hydrothermal method. Weigh 0.02 mol of FeCl3·6H2O and 0.01 mol of Ni(NO3)2·6H2O compounds, add them to deionized water, and ultrasonically disperse and dissolve them. Add a certain amount of NH3·H2O solution to form a suspension, then centrifuge at a speed of 8000 revolutions per minute for 5 minutes. After that, add 60 mL of a solution containing 15 g of NaOH to the precipitate. Place the suspension in the inner lining of a 100 mL polytetrafluoroethylene reaction kettle, and then react at 180 °C for 18 h. Use a magnet to attract the product NiFe2O4, wash it 3 times with ethanol and water respectively, and then dry and grind it.
[0050] After testing, the final product is BiOI / NiFe2O4, and the magnetic nanoparticles are in-situ loaded on the BiOI nanoflowers. Under magnetic drive and simulated sunlight by a xenon lamp (300 W), the magnetic-driven micro-nano robot has excellent bactericidal effect.
[0051] Example 5
[0052] The magnetic nanoparticles selected in this example are CuFe2O4, and the rest is the same as Example 1.
[0053] (1) Prepare magnetic ferrite spinel nanoparticles by hydrothermal method. Weigh 0.02 mol of FeCl3·6H2O and 0.01 mol of CuSO4·5H2O compounds, add them to deionized water, and ultrasonically disperse and dissolve them. Add a certain amount of NH3·H2O solution to form a suspension, then centrifuge at a speed of 8000 revolutions per minute for 5 minutes. After that, add 60 mL of a solution containing 15 g of NaOH to the precipitate. Place the suspension in the inner lining of a 100 mL polytetrafluoroethylene reaction kettle, and then react at 180 °C for 18 h. Use a magnet to attract the product CuFe2O4, wash it 3 times with ethanol and water respectively, and then dry and grind it.
[0054] After testing, the final product is BiOI / CuFe2O4, and the magnetic nanoparticles are in-situ loaded on the BiOI nanoflowers. Under magnetic drive and simulated sunlight by a xenon lamp (300 W), the magnetic-driven micro-nano robot has excellent bactericidal effect.
[0055] Example 6
[0056] The magnetic nanoparticles selected in this example are ZnFe2O4, and the rest is the same as Example 1.
[0057] (1) Prepare magnetic ferrite spinel nanoparticles by hydrothermal method: Weigh 0.02 mol of FeCl3·6H2O and 0.01 mol of Zn(CH3COO)2·2H2O compounds, add them to deionized water, and disperse and dissolve them by ultrasonic treatment. Add a certain amount of NH3·H2O solution to form a suspension, then centrifuge it at a speed of 8000 revolutions per minute for 5 minutes. After that, add 60 mL of a solution containing 15 g of NaOH to the precipitate. Place the suspension in the inner lining of a 100 mL polytetrafluoroethylene reaction kettle, and then react at 180 °C for 18 h. Use a magnet to attract the product ZnFe2O4, wash it 3 times with ethanol and water respectively, and then dry and grind it.
[0058] After testing, the final product is BiOI / CuFe2O4, and the magnetic nanoparticles are in-situ loaded on the BiOI nanoflowers. Under the magnetic drive and simulated sunlight (300 W) of a xenon lamp, the magnetic-driven micro-nano robot has excellent bactericidal effects.
[0059] In summary, the invention includes but is not limited to the above embodiments. Any equivalent replacement or partial improvement made under the spirit and principle of the present invention will be regarded as within the protection scope of the present invention.
Claims
1. A magnetically driven micro-nano robot based on photocatalysis, characterized in that: Bismuth oxyhalide is used as a carrier, and spinel ferrite magnetic nanoparticles are loaded on the carrier surface. The molecular formula of spinel ferrite is MFe2O4, M is a divalent metal ion, the bismuth oxyhalide is BiOI with a flower-like structure, and the molar ratio of the carrier to the magnetic nanoparticles is 1:0.25-1.
2. A magnetically driven micro-nano robot based on photocatalysis as claimed in claim 1, characterized in that: The flower-like structure is composed of BiOI nanosheets, and / or the molar ratio of the carrier to the magnetic nanoparticles is 1:0.4-0.
7.
3. The magnetically driven micro-nano robot based on photocatalysis according to claim 1, characterized in that: The M element is Fe, Mn, Co, Ni, Cu or Zn; the spinel ferrite magnetic nanoparticles are Fe3O4, MnFe2O4, CoFe2O4, NiFe2O4, CuFe2O4 or ZnFe2O4; preferably, the spinel ferrite magnetic nanoparticles are MnFe2O4.
4. The magnetically driven micro-nano robot based on photocatalysis according to claim 1, characterized in that: The particle size of the spinel ferrite magnetic nanoparticles is 50 to 1000 nm.
5. A method for preparing a magnetically driven micro-nano robot based on photocatalysis according to any one of claims 1 to 4, characterized in that: The method steps include: (1) preparing spinel ferrite magnetic nanoparticles; (2) Adding spinel ferrite magnetic nanoparticles to KI solution, ultrasonically dispersing them uniformly, adding bismuth nitrate ethylene glycol solution under mechanical stirring, stirring for 4 to 8 hours, collecting the solids by centrifugation, washing and drying to obtain a magnetically driven micro-nano robot based on photocatalysis.
6. The method for preparing a magnetically driven micro-nano robot based on photocatalysis according to claim 5, characterized in that: In step (1), the iron source and the M source are mixed and dissolved to obtain a precursor solution; ammonia water is added dropwise to obtain a suspension; the precipitate is collected by centrifugation, the pH is adjusted to 9-11 with a NaOH solution, and then placed in a hydrothermal reactor, reacted at 120-180° C. for 12-24 hours, naturally cooled, washed, and dried to obtain spinel ferrite magnetic nanoparticles.
7. The method for preparing a magnetically driven micro-nano robot based on photocatalysis according to claim 6, characterized in that: The iron source and M source include one or more of chlorides, sulfates, nitrates and acetates of the corresponding metal elements.
8. The method for preparing a magnetically driven micro-nano robot based on photocatalysis according to claim 5, characterized in that: In step (2), the molar ratio of the spinel ferrite magnetic nanoparticles to KI is 0.25 to 1:1; preferably 0.4 to 0.7:1; and the molar ratio of KI to bismuth nitrate is 1 to 5:
1.
9. An application of a magnetically driven micro-nano robot based on photocatalysis as claimed in any one of claims 1 to 4, characterized in that: The magnetically driven micro-nano robot is used as a photocatalytic broad-spectrum bactericidal agent.
10. The use of a magnetically driven micro-nano robot based on photocatalysis as claimed in claim 9, characterized in that: The magnetically driven micro-nano robot is added into a solution of pathogenic bacteria to be killed, and sterilization is achieved under light and an external magnetic field; Preferably, the pathogenic bacteria include Mycobacterium tuberculosis, Staphylococcus, Salmonella, Escherichia coli and Bacillus anthracis; preferably, the light absorption range of the magnetically driven micro-nano robot is 200-1000nm; the light source includes sunlight, LED lamp and xenon lamp.