Preparation method of copper monatomic bactericidal material

Abstract

The invention relates to a preparation method of a copper monatomic bactericidal material. According to the invention, a solid oxide or a carbon material is used as a carrier, and the carrier, nano-copper and a phenolic compound aqueous solution are mixed and stirred in a dark place at an ambient temperature. A phenolic compound, especially an ortho-phenolic hydroxyl group of catechol, is preferentially combined with nano-copper, destroys metallic bonds on the surface of the nano-copper, mediates the nano-copper to dissociate layer by layer, stabilizes the nano-copper into a monatomic state and finally uniformly anchors the nano-copper on the surface of a carrier to form a stable copper monatomic material, the method is carried out under environmental conditions, the preparation steps are simple, the synthesis time is short, and the method is suitable for industrial production. And large equipment is not needed. The sterilization efficiency of the obtained copper monatomic material on escherichia coli is improved by 15 times compared with that of nano-copper, but the dissolution rate of copper ions is reduced by 87%. The material is suitable for long-acting antibiosis of medical instruments, water treatment systems and food packaging surfaces.

Description

Technical Field

[0001] This invention relates to a method for preparing a copper single-atom bactericidal material, belonging to the field of materials preparation technology. Background Technology

[0002] With the increasing advancement of science and technology, people's requirements for environmental hygiene have become more stringent, making the preparation and application of bactericidal materials particularly important. Nano-copper, due to its broad-spectrum and highly efficient bactericidal activity, has long been widely used in various antibacterial fields. However, it has significant limitations: (1) It is easily oxidized in air or aqueous solutions, leading to excessive dissolution of copper ions, causing not only rapid loss of active ingredients but also potential environmental risks with long-term use; (2) Its high surface energy makes it prone to aggregation, resulting in a decrease in effective specific surface area and a significant reduction in bactericidal activity; (3) The copper loading in bactericidal materials is relatively large, leading to high usage costs and significant environmental hazards. Therefore, improving the bactericidal efficiency of nano-copper while minimizing the copper loading is an important and challenging task, and also the future development direction of copper-based bactericides. In recent years, single-atom materials have demonstrated higher activity and stability than metal nanoparticles in many fields due to their highest atomic utilization and controllable coordination environment. However, the preparation of traditional single-atom materials usually relies on high-temperature reduction (>600°C) or complex processes (such as atomic layer deposition, photo / electrochemical deposition). These methods are not only costly and energy-intensive, but also require demanding equipment, making large-scale production difficult. The preparation methods described in patent document CN119680605A mostly involve high-temperature carbonization or complex synthesis steps, and the simple, low-temperature preparation of copper single-atom materials still faces significant challenges. Therefore, developing a copper single-atom material preparation technology that can be carried out under mild conditions, with simple steps, low equipment requirements, and easy scale-up is of great significance for improving the performance, stability, and economy of copper-based antibacterial materials and promoting their widespread application in fields such as medicine, water treatment, and food packaging. Summary of the Invention

[0003] This invention addresses the problems of easy oxidation and dissolution, easy aggregation and deactivation of existing copper-based nanomaterials, as well as the complex, costly and difficult-to-scale preparation processes of traditional single-atom materials. This invention provides a method for preparing copper single-atom bactericidal materials.

[0004] This invention fully utilizes the chemical property of nano-copper to easily form complexes. By directly mediating the atomization of nano-copper through phenolic compounds (especially catechol) at ambient temperature (20-40℃), copper single atoms are loaded onto the surface of a support in one step to obtain copper single-atom materials. The preparation method is efficient and simple, does not require expensive reduction steps, and can be completed in one step, allowing for mass production. Invention Overview: This invention uses solid oxides or carbon materials as a carrier. Under ambient temperature, the carrier, nano-copper, and an aqueous solution of phenolic compounds are mixed and stirred in the dark. The phenolic compounds, especially the ortho-hydroxyl groups of catechol, preferentially bind to the nano-copper, breaking the metallic bonds on the surface of the nano-copper, mediating its layer-by-layer dissociation and stabilization into a single-atom state, and finally uniformly anchored on the surface of the carrier to form a stable copper single-atom material. Invention Details: The specific technical solution of this invention is as follows: A method for preparing a copper single-atom bactericidal material includes the following steps: A solid carrier, a nano-copper source, and an aqueous solution of a phenolic compound are mixed and stirred in the dark. The phenolic compound is either catechol or hydroquinone. The reaction mixture is centrifuged, washed, and vacuum dried to obtain a copper single-atom bactericidal material.

[0007] According to a preferred embodiment of the present invention, the solid support is selected from alumina, iron oxide, or porous carbon.

[0008] According to a preferred embodiment of the present invention, the alumina is α / γ-alumina, the iron oxide is Fe3O4 or α / γ-Fe2O3, and the porous carbon is activated carbon, carbon molecular sieve, carbon foam, or biochar.

[0009] According to a preferred embodiment of the present invention, the particle size of the carrier is 5 nm-5 μm.

[0010] According to a preferred embodiment of the present invention, the source of nano-copper is nano-copper powder, nano-copper solution, nano-copper slurry, or nano-copper paste.

[0011] According to a preferred embodiment of the present invention, the particle size of the nano-copper powder is 10-50 nm.

[0012] According to a preferred embodiment of the present invention, the phenolic compound is catechol.

[0013] According to a preferred embodiment of the present invention, the concentration of the aqueous solution of the phenolic compound is 0.1-20M; More preferably, the concentration of the phenolic compound solution is 0.5-10M; Most preferably, the concentration of the phenolic compound solution is 1-5M.

[0014] According to a preferred embodiment of the present invention, the mass-to-volume ratio of the solid carrier to the aqueous solution of the phenolic compound is (1-10):(200-500), unit: g / mL.

[0015] More preferably, the mass-to-volume ratio of the solid carrier to the aqueous solution of the phenolic compound is (1-10):(300-500), unit: g / mL.

[0016] According to a preferred embodiment of the present invention, the mass-to-volume ratio of the nano-copper source to the aqueous solution of the phenolic compound is (30-70):(300-500), unit: mg / mL.

[0017] According to a preferred embodiment of the present invention, the mass-to-volume ratio of the nano-copper source to the aqueous solution of the phenolic compound is (40-50):(300-500), unit: mg / mL.

[0018] According to a preferred embodiment of the present invention, the reaction time with stirring in the dark is 2-48 hours, and the reaction temperature is 20-40°C.

[0019] According to a preferred embodiment of the present invention, the centrifugation speed is 3000-12000 rpm and the centrifugation time is 5-15 min.

[0020] According to a preferred embodiment of the present invention, the vacuum drying temperature is 50-150°C and the vacuum drying time is 2-48 hours.

[0021] A copper single-atom bactericidal material is prepared by the method described above.

[0022] The aforementioned copper single-atom bactericidal materials are used for sterilization in medical device coatings, water treatment filter cartridges, or antibacterial films for food packaging.

[0023] In this invention, the phenolic hydroxyl groups of catechol and hydroquinone, especially the ortho-hydroxyl groups, preferentially bind to nano-copper, disrupting the metallic bonds on the surface of the nano-copper. This mediates the layer-by-layer dissociation and stabilization into a single-atom state, ultimately resulting in uniform anchorage on the carrier surface. The use of phenolic compounds significantly improves the generation efficiency of copper single atoms. The resulting copper single atoms are fixed by functional groups on the carrier surface and exhibit a near-zero valence state. The copper single-atom material prepared by this invention exhibits superior bactericidal activity compared to nano-copper.

[0024] Technical features and advantages of the present invention: 1. The method of this invention utilizes nano-copper as a copper source, and directly atomizes the copper source into copper single atoms through phenolic substances, ultimately obtaining copper single-atom materials. The copper single atoms are stabilized by the functional groups on the surface of the carrier, enabling them to remain stable under reducing conditions, while avoiding the aggregation of copper atoms, thus improving the stability of the copper single atoms and ensuring the strong and long-lasting bactericidal properties of the bactericidal material.

[0025] 2. The single-atom bactericidal material obtained by this invention can significantly reduce the amount of copper used, while having a stronger bactericidal effect than nano-copper, achieving a high bactericidal efficiency in a short time. The copper single-atom material has a 15-fold higher bactericidal efficiency against Escherichia coli than nano-copper, and the copper ion leaching rate is reduced by 87%.

[0026] 3. This invention prepares copper single-atom bactericidal materials in a one-step process. The conditions are mild, the steps are simple, the synthesis time is short, no large-scale equipment is required, and it is easy to promote and apply.

[0027] 4. The copper single-atom bactericidal material of the present invention has a wide range of applications. It can be used for sterilization on solid surfaces and inside liquids, and can be applied to sterilization in medical device coatings, water treatment filter cartridges or antibacterial films for food packaging. Attached Figure Description

[0028] Figure 1 Aberration-corrected transmission electron microscope image of the copper single-atom bactericidal material prepared in Example 1.

[0029] Figure 2 Transmission electron microscope image of the copper single-atom bactericidal material prepared in Example 1.

[0030] Figure 3 These are electron spin resonance spectra of different materials.

[0031] Figure 4 The UV diffuse reflectance spectra of different bactericidal materials are shown.

[0032] Figure 5 XRD patterns of different bactericidal materials.

[0033] Figure 6 Transmission electron microscope image of the nano-copper bactericidal material prepared for Comparative Example 1.

[0034] Figure 7 The diagram shows the bactericidal kinetics of different bactericidal materials. Detailed Implementation

[0035] Detailed embodiments shown: In order to enable those skilled in the art to fully understand the technical solution and beneficial effects of the present invention, the present invention will be further described below in conjunction with specific embodiments and accompanying drawings.

[0036] Example 1 The preparation method of copper single-atom bactericidal material includes the following steps: 1) Add 1g Al2O3 (γ type, 40nm) and 40mg of nano copper powder (20 nm) to 400 mL of 0.1M catechol aqueous solution. Wrap the beaker with aluminum foil to protect it from light and stir magnetically at 25℃ for 24 hours.

[0037] 2) After stirring, centrifuge the reaction solution at 10,000 rpm for 5 min to remove the supernatant; wash the solid three times with deionized water, and then dry it in a vacuum drying oven at 40℃ for 20 h to obtain the copper single-atom bactericidal material Cu1 / Al2O3.

[0038] Aberration-corrected transmission electron microscope image of the copper single-atom bactericidal material prepared in this embodiment is shown below. Figure 1 ,pass Figure 1 As can be seen, copper in the single-atom bactericidal material Cu1 / Al2O3 of this embodiment exists in the form of single atoms; transmission electron microscope images are shown below. Figure 2 No obvious nano-copper or copper clusters were observed. The electron spin resonance spectrum is shown below. Figure 3 It can be seen that copper single atoms exhibit a zero valence state, indicating that copper single atoms exhibit a low valence state close to zero.

[0039] The ultraviolet diffuse reflectance spectrum of the copper single-atom bactericidal material prepared in this embodiment is shown below. Figure 4 It can be seen that the SPR characteristic peak of nano-copper is not present in the copper single-atom bactericidal material Cu1 / Al2O3; XRD shows... Figure 5 It can be seen that there is no nano-copper in the copper single-atom bactericidal material Cu1 / Al2O3, indicating that the nano-copper has been completely converted into copper single atoms, with a high conversion rate.

[0040] Example 2 The method for preparing the highly efficient copper single-atom bactericidal material described in Example 1 differs from the following: In step 1), the concentration of the catechol aqueous solution is 5M, and the rest is carried out as in Example 1.

[0041] Example 3 The method for preparing the highly efficient copper single-atom bactericidal material described in Example 1 differs from the following: In step 1), the concentration of the catechol aqueous solution is 1M, and the rest is carried out as in Example 1.

[0042] Example 4 The method for preparing the highly efficient copper single-atom bactericidal material described in Example 1 differs from the following: In step 1), the concentration of the catechol aqueous solution is 2M, and the rest is carried out as in Example 1.

[0043] Example 5 The method for preparing the highly efficient copper single-atom bactericidal material described in Example 1 differs from the following: In step 1), Al2O3 (γ-type, 40nm) was replaced with 200-mesh coconut shell charcoal, and the rest was carried out as in Example 1.

[0044] Example 6 The method for preparing the highly efficient copper single-atom bactericidal material described in Example 1 differs from the following: In step 1), Al2O3 (γ-type, 40nm) was replaced with Fe3O4, and the rest was carried out as in Example 1.

[0045] Example 7 The method for preparing the highly efficient copper single-atom bactericidal material described in Example 1 differs from the following: In step 1), the average particle size of the copper nanoparticles is 100 nm, and the rest is carried out as in Example 1.

[0046] Comparative Example 1 The preparation method is the same as that described in Example 1, except that: Step 1) is an aqueous solution in which no phenolic substances are added.

[0047] Finally, the nano-copper bactericidal material Cu was obtained. NP / Al2O3.

[0048] The prepared nano-copper bactericidal material Cu NP The transmission electron microscope image of Al2O3 can be found here. Figure 6 .pass Figure 6 It can be seen that a large amount of nano-copper can be observed without the use of phenolic substances, which also indicates that catechol can promote the formation of copper single atoms; the electron spin resonance spectrum is shown below. Figure 3 This indicates that Cu NP / Copper single atoms are not present in Al2O3; see the UV diffuse reflectance spectrum. Figure 4 Cu NP The SPR characteristic peaks of nano-copper were present in Al2O3; XRD pattern is shown below. Figure 5 Cu NP Nano-copper exists in Al2O3.

[0049] In summary, this demonstrates that without the use of phenolic substances, it is impossible to promote the formation of copper single atoms.

[0050] Comparative Example 2 The method for preparing the highly efficient copper single-atom bactericidal material described in Example 1 differs from the following: The reaction time in step 1) is 10 h.

[0051] The final product is a bactericidal material composed of copper single atoms and nano-copper, Cu1+Cu. NP / Al2O3.

[0052] Cu1+Cu, a bactericidal material composed of copper single atoms and nano-copper. NP See the electron spin resonance spectrum of Al2O3. Figure 3 This indicates that Cu1+Cu NP Copper single atoms are present in Al2O3; the ultraviolet diffuse reflectance spectrum is shown below. Figure 4 It is evident that nano-copper is present. This indicates that the short reaction time resulted in incomplete conversion of the nano-copper.

[0053] Comparative Example 3 The preparation method is the same as that described in Example 1, except that: Step 1) Without adding any copper source, Al2O3 is obtained after being soaked in an aqueous phenol solution.

[0054] XRD pattern of Al2O3 soaked in phenolic aqueous solution is shown below. Figure 5 It can be seen that the morphology and crystal structure of Al2O3 soaked in phenolic aqueous solution do not change compared to Al2O3 that has not been soaked.

[0055] Experimental Example sterilization experiment (1) Prepare Luria-Bertani (LB) solid culture medium and liquid culture medium respectively. Solid culture medium: 2.5g yeast extract, 5g sodium chloride, 5g tryptone, 9g agar, 500mL deionized water.

[0056] Liquid culture medium: 2.5g yeast extract, 5g sodium chloride, 5g tryptone, 500mL deionized water.

[0057] Solid and liquid culture media are sterilized by high temperature and high pressure.

[0058] (2) Bacteria were cultured in LB liquid medium for 24 hours, and the resulting bacterial culture was diluted to 10⁻⁶. 7 ufc / mL, take 5mL of the diluted bacterial solution and mix it with the fungicide of Example 1 and Comparative Examples 1-3 respectively (the concentration of the fungicide is 15mg / mL), and place it in a shaking incubator (37). o Shake at 180 rpm for 20 minutes (C, 180 rpm / min). Every 20 minutes, take 50 μL of bacterial culture and spread it onto the surface of a solid culture medium. Then place the medium at 37°C. o The samples were grown in a C incubator, with three parallel samples taken from each group.

[0059] The bactericidal kinetics of different bactericidal materials are shown in Figure 7 It can be clearly seen that the bactericidal effect of the copper single-atom bactericidal material synthesized by the present invention is significantly better than that of comparative examples 1-3.

Claims

1. A method for preparing a copper single-atom bactericidal material, comprising the following steps: A solid carrier, a nano-copper source, and an aqueous solution of a phenolic compound are mixed and stirred in the dark. The phenolic compound is either catechol or hydroquinone. The reaction mixture is centrifuged, washed, and vacuum dried to obtain a copper single-atom bactericidal material.

2. The preparation method according to claim 1, characterized in that, The solid support is selected from alumina, iron oxide, or porous carbon. The alumina is α / γ-alumina, the iron oxide is Fe3O4 or α / γ-Fe2O3, and the porous carbon is activated carbon, carbon molecular sieve, carbon foam, or biochar. The particle size of the support is 5 nm-5 μm.

3. The preparation method according to claim 1, characterized in that, The source of nano-copper is nano-copper powder, nano-copper solution, nano-copper slurry or nano-copper paste, and the particle size of nano-copper powder is 10-50nm.

4. The preparation method according to claim 1, characterized in that, The phenolic compound is catechol.

5. The preparation method according to claim 1, characterized in that, The concentration of the aqueous solution of phenolic compounds is 0.1-20M, preferably 0.5-10M; most preferably 1-5M.

6. The preparation method according to claim 1, characterized in that, The mass-volume ratio of the solid carrier to the aqueous solution of the phenolic compound is (1-10):(200-500), unit: g / mL. Preferably, the mass-volume ratio of the solid carrier to the aqueous solution of the phenolic compound is (1-10):(300-500), unit: g / mL.

7. The preparation method according to claim 1, characterized in that, The mass-volume ratio of the nano-copper source to the aqueous solution of the phenolic compound is (30-70):(300-500), unit: mg / mL. Preferably, the mass-volume ratio of the nano-copper source to the aqueous solution of the phenolic compound is (40-50):(300-500), unit: mg / mL.

8. The preparation method according to claim 1, characterized in that, The reaction time is 2-48 hours with stirring in the dark, the reaction temperature is 20-40℃, the centrifugation speed is 3000-12000 rpm, the centrifugation time is 5-15 minutes, the vacuum drying temperature is 50-150℃, and the vacuum drying time is 2-48 hours.

9. A copper single-atom bactericidal material, prepared by the method described in any one of claims 1-8.

10. The application of the copper single-atom bactericidal material according to claim 9, for sterilization in medical device coatings, water treatment filter cartridges, or antibacterial films for food packaging.

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