Preparation method of hydrophilic Co-MOFs-based material

Abstract

The invention belongs to the technical field of metal organic framework materials, and discloses a hydrophilic Co-MOFs-based material preparation method, which comprises: dissolving a Co metal salt, an organic ligand I and an organic ligand II in an organic solvent to obtain a precursor solution, sequentially adding an organic alcohol, deionized water and an organic amine to the precursor solution, and carrying out a reaction to obtain the hydrophilic Co-MOFs-based material. After uniform suspension liquid is obtained through mixing, the suspension liquid is centrifuged, precipitates are collected, washed and dried, and the hydrophilic Co-MOFs-based material is obtained. The hydrophilic Co-MOFs-based material prepared by the method disclosed by the invention has excellent antibacterial property, dispersion stability and durability.

Description

Technical Field

[0001] This invention belongs to the field of metal-organic framework materials technology, and relates to a method for preparing hydrophilic Co-MOFs-based materials. Background Technology

[0002] Metal-organic frameworks (MOFs) are porous materials formed by organic ligands and metal ions linked by coordination bonds. They have extremely high specific surface area and adjustable pore size, showing broad application prospects in adsorption separation and other fields.

[0003] In recent years, the regulation of the hydrophilicity and hydrophobicity of MOF materials has become a research hotspot. Researchers have utilized their tunable hydrophilic and oleophilic properties to achieve simple and efficient adsorption of water and oil. Some of these research results have already been preliminarily applied in practical scenarios such as oil-water separation, but many problems still need to be solved.

[0004] In Reference 1 (Superhydrophobic sponge decorated with hydrophobic MOF-5 nanocoating for efficient oil-water separation and antibacterial applications[J]. Sustainable Materials and Technologies, 2022, 33: e00492), researchers modified superhydrophobic MOF-5 nanoparticles with low surface energy PFOTS material, and prepared MOF-5-modified superhydrophobic sponges through a simple dip-coating method, exploring their dual applications in oil-water separation and antibacterial fields. Although this material has advantages such as high separation efficiency, reusability, and antibacterial activity, the hydrophobicity control process requires additional modification treatment, resulting in poor material durability.

[0005] In Reference 2 (Self-assembled MOF membranes with underwater superoleophobicity for oil / water separation[J]. Journal of Membrane Science, 2018, 566: 268), researchers prepared a separation membrane with high hydrophilicity and underwater superoleophobicity by compositing modified UiO-66-NH2 MOFs with polyacrylic acid. The separation efficiency of oil / water emulsion reached 99.9%. However, the function of this MOF base membrane material is relatively simple, only able to achieve oil-water separation, and it does not have antibacterial properties, making it difficult to meet the application requirements of complex scenarios.

[0006] In summary, the hydrophilic MOF-based materials reported so far generally have obvious defects: hydrophilicity and hydrophobicity control requires additional low surface energy modification treatment, the materials have poor durability, single function and most do not have antibacterial properties, and the materials have insufficient stability.

[0007] Therefore, developing a method for preparing hydrophilic Co-MOFs-based materials to effectively solve the above problems is of great research significance for promoting the practical application of MOFs materials in fields such as oil-water separation and antibacterial properties. Summary of the Invention

[0008] The purpose of this invention is to address the problems existing in the prior art and provide a method for preparing hydrophilic Co-MOFs-based materials.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0010] A method for preparing a hydrophilic Co-MOFs-based material involves sequentially adding an organic alcohol, deionized water, and an organic amine to a precursor solution, magnetically stirring at 20-30°C for 3-6 hours to obtain a uniform suspension, centrifuging the suspension to collect the precipitate, washing and drying it to obtain the hydrophilic Co-MOFs-based material.

[0011] This invention utilizes organic alcohols and deionized water to better dissolve all reactants (such as Co metal salts, organic ligands I and II), while simultaneously deprotonating organic ligand I via organic amines, thereby enabling it to react with Co. 2+ Metal ions form metallic bonds, ultimately leading to the formation of the MOF.

[0012] The precursor solution is obtained by dissolving Co metal salt, organic ligand I, and organic ligand II in an organic solvent;

[0013] Organic ligand I is (CAS: 22803-05-0) (CAS: 2631705-26-3) (CAS: 1937251-31-4) or (CAS: 681179-19-1);

[0014] Organic ligand II is (CAS: 1159202-33-1) (CAS: 4877-80-9) (CAS: 105598-27-4) (CAS: 1374854-57-5) or (CAS: 1821122-35-3).

[0015] As a preferred technical solution:

[0016] In the preparation method of the hydrophilic Co-MOFs-based material described above, the organic alcohol is methanol, ethanol, n-propanol or isopropanol.

[0017] In the preparation method of the hydrophilic Co-MOFs-based material described above, the organic amine is trimethylamine, triethylamine, or tripropylamine.

[0018] The preparation method of the hydrophilic Co-MOFs-based material described above uses Co metal salts such as CoCl2, CoCl2·6H2O, Co(NO3)2, Co(NO3)2·6H2O, CoSO4, or CoSO4·7H2O.

[0019] The method for preparing a hydrophilic Co-MOFs-based material as described above uses DMF (N,N-dimethylformamide), DMSO (dimethyl sulfoxide), or DMAc (N,N-dimethylacetamide) as the organic solvent.

[0020] The preparation method of the hydrophilic Co-MOFs-based material described above involves washing with ethanol 3 to 5 times; drying at a temperature of 40 to 60°C for 4 to 12 hours.

[0021] The preparation method of the hydrophilic Co-MOFs-based material described above uses a molar ratio of Co metal salt, organic ligand I, organic ligand II, deionized water, organic solvent, organic alcohol and organic amine of 1:2.1~2.3:1.1~1.5:100~200:100~200:30~50:10~20.

[0022] The method described above for preparing hydrophilic Co-MOFs-based materials results in a specific surface area of ​​1729~1983 m². 2 / g, pore volume 2.3~5.6cm 3 / g, pore size 1.23~4.77nm, water contact angle 10°~20°;

[0023] The zeta potential of hydrophilic Co-MOF-based materials in aqueous phase is -36 to -45 mV;

[0024] The hydrophilic Co-MOFs-based materials have an antibacterial rate of 99.3-99.7% against Escherichia coli and an antibacterial rate of 99.4-99.9% against Staphylococcus aureus.

[0025] Invention principle:

[0026] The Co-MOF of this invention employs a novel multi-carboxyl semi-rigid organic ligand. When this ligand coordinates with Co(II) ions, it does not form a simple, repeating extended structure, but rather a highly cross-linked and partially interlocked three-dimensional network through a multi-coordination mode of carboxyl groups and metal clusters. This network topology significantly reduces the symmetry of the framework, resulting in the carboxyl groups not being uniformly distributed at the nanoscale, but rather forming locally high-density, negatively charged regions at specific "nodes" and "connections" of the framework skeleton.

[0027] Due to the unique topological structure described above, the surface and internal channels of this Co-MOF nanoparticle exhibit a chemical microenvironment gradient. The interior of the framework mainly consists of relatively hydrophobic regions composed of aromatic rings of ligands, while the framework surface and near-surface pores are covered by a large number of uncoordinated or only monodentate carboxylate groups, forming a dynamic, negatively charged, hydrophilic "carboxylated shell." This is difficult to achieve with conventional high-symmetry Co-MOFs.

[0028] The antibacterial activity of the Co-MOFs of this invention originates from a multimodal synergistic mechanism driven by their unique structure and chemical properties. On one hand, the controlled dissociation of Co-MOFs in an aqueous environment enables the continuous and stable release of biotoxic Co. 2+ Ions can adsorb onto the negatively charged bacterial cell surface through electrostatic interactions, disrupting the stability of the cell membrane phospholipid bilayer, increasing membrane permeability, leading to leakage of cell contents and membrane potential collapse. On the other hand, Co... 2+ After penetrating into the cell interior, Co acts as a catalytic center, inducing intense oxidative stress. 2+ It can mimic the peroxidase-catalyzed conversion of endogenous hydrogen peroxide, efficiently generating highly reactive oxygen species (ROS) such as hydroxyl radicals; its variable valence state (Co) 2+ / Co 3+ Oxidative oxidative stresses (ROS) can interfere with the intracellular electron transport chain, further promoting the explosive accumulation of ROS, thereby causing irreversible oxidative damage to key biomolecules such as proteins, lipids, and nucleic acids. In contrast, the negatively charged carboxyl groups in Co-MOFs can generate strong electrostatic attraction with the positively charged bacterial cell membranes (such as the surface of many Gram-positive bacteria), causing Co-MOFs to firmly anchor on the bacterial surface and significantly increasing the oxidation-reduction potential of Co-MOFs. 2+ Local concentration and contact efficiency. In addition, the introduction of hydrophilic groups into the ligands of Co-MOFs gives them a higher affinity for the bacterial cell wall, allowing the sharp edges and nanostructures of Co-MOFs to directly physically penetrate and mechanically damage the bacterial cell membrane.

[0029] Organic ligands containing multiple carboxyl groups are more readily deprotonated in aqueous environments compared to groups such as -OH, forming negatively charged carboxylate ions. This results in a persistent and strong negative charge on the surface of Co-MOF molecules, leading to a high negative zeta potential. This excellent zeta potential stability ensures that Co-MOF nanoparticles can be uniformly and persistently dispersed in solutions or on coating surfaces, effectively penetrating and disrupting existing biofilm structures and eliminating stubborn bacteria encapsulated within the membrane—a weakness of many other MOFs.

[0030] The strong hydrophilicity of the outer layer facilitates initial wetting and access, while the relatively hydrophobic regions near the surface and interior may interfere with hydrophobic extracellular polymers or the cell membrane itself within the biomembrane through hydrophobic interactions. This gradient design of a "hydrophilic shell-hydrophobic core" allows it to simultaneously disrupt the stability of the biomembrane from both electrostatic and hydrophobic perspectives when penetrating and remaining inside, synergistically releasing Co. 2+ It kills encapsulated bacteria from the inside, solving the problem that conventional antibacterial materials have difficulty removing biofilms.

[0031] The intermolecular interactions of Co-MOFs are mainly determined by van der Waals attraction and electrostatic repulsion of the electric double layer. Due to their high surface charge and charge distribution, the electrostatic repulsion between molecules is strong, resulting in a high zeta potential and high system stability. Furthermore, the carboxylated structures on the material surface can bind a large number of water molecules through hydrogen bonds, forming a hydrophilic shell. This shell not only exerts a steric hindrance effect, preventing close-range contact and aggregation of particles, but also works synergistically with the electrostatic repulsion to further enhance the system's stability.

[0032] The stability of this invention stems from the "stereo-electrostatic dual stabilizing layer" generated by its unique structure.

[0033] The structure exhibits strong electrostatic repulsion—a locally high-density array of carboxylate groups on the framework surface (derived from unconventional topology)—allowing it to generate a stronger and more persistent surface negative charge in aqueous solution than uniformly distributed carboxyl groups. The measured absolute value of the zeta potential is significantly higher than that of known Co-MOFs with similar structures. This provides a powerful long-range electrostatic repulsion force.

[0034] The structure with ultra-large steric hindrance—the unique "carboxylated shell" binds water molecules through hydrogen bonds, forming not a single-layer hydration layer, but a thick "structured hydration layer" due to the dense spatial arrangement and specific orientation of carboxyl groups, thus constituting a rigid physical barrier.

[0035] Therefore, the rigid framework of "cross-linking and interlocking" ensures that the particle core is not easily deformed or disintegrated when subjected to external forces or concentration changes, thus ensuring the integrity of the "stereo-electrostatic dual-stabilization layer" on its surface; electrostatic repulsion prevents particles from approaching each other from a distance, while the thick structured hydration layer provides the final line of defense at close range. The two work together to achieve "double insurance" against aggregation, thereby ensuring excellent long-term dispersion stability.

[0036] Furthermore, the excellent dispersion stability of the Co-MOF of this invention ensures that sufficient and complete active nanounits continuously act on bacteria and biofilms throughout the antibacterial process, rather than becoming inactive due to aggregation. This is the structural guarantee for achieving long-lasting and highly efficient antibacterial effects.

[0037] Beneficial effects:

[0038] (1) This invention utilizes the multimodal synergistic mechanism driven by the unique structure and chemical properties of hydrophilic Co-MOFs-based materials to give them excellent antibacterial properties.

[0039] (2) The hydrophilic Co-MOFs-based material of the present invention has excellent zeta potential stability, ensuring that Co-MOF nanoparticles can be uniformly and persistently dispersed in solution or on coating surface, effectively penetrating and destroying the formed biofilm structure, removing stubborn bacteria encapsulated in the membrane, and enabling Co to... 2+ It kills encapsulated bacteria from the inside, solving the problem that conventional antibacterial materials have difficulty removing biofilms.

[0040] (3) The unique structure of the hydrophilic Co-MOFs-based material of the present invention produces a “stereo-electrostatic dual-stabilized layer” that ensures long-term excellent dispersion stability. The excellent dispersion stability of Co-MOF ensures that sufficient and complete active nanounits continuously act on bacteria and biofilms throughout the antibacterial process, rather than becoming inactive due to aggregation. This is the structural guarantee for achieving long-lasting and efficient antibacterial effects. Attached Figure Description

[0041] Figure 1 This is a schematic diagram illustrating the synthesis of the hydrophilic Co-MOFs-based material of the present invention;

[0042] Figure 2 The 1H NMR spectrum of the Co-MOFs prepared in Example 1 of this invention;

[0043] Figure 3 The carbon NMR spectrum of the Co-MOFs prepared in Example 1 of this invention;

[0044] Figure 4 The 1H NMR spectrum of the Co-MOFs prepared in Example 2 of this invention;

[0045] Figure 5 The carbon NMR spectrum of the Co-MOFs prepared in Example 2 of this invention;

[0046] Figure 6 The 1H NMR spectrum of the Co-MOFs prepared in Example 3 of this invention;

[0047] Figure 7 The carbon NMR spectrum of the Co-MOFs prepared in Example 3 of this invention;

[0048] Figure 8 The 1H NMR spectrum of the Co-MOFs prepared in Example 4 of this invention;

[0049] Figure 9 The carbon NMR spectrum of the Co-MOFs prepared in Example 4 of this invention;

[0050] Figure 10 The 1H NMR spectrum of the Co-MOFs prepared in Example 5 of this invention;

[0051] Figure 11 The carbon NMR spectrum of the Co-MOFs prepared in Example 5 of this invention;

[0052] Figure 12 The 1H NMR spectrum of the Co-MOFs prepared in Example 6 of this invention;

[0053] Figure 13 The carbon NMR spectrum of the Co-MOFs prepared in Example 6 of this invention. Detailed Implementation

[0054] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0055] The manufacturers and brands mentioned in the following embodiments are merely examples. The core of this invention lies in the technical solution itself, and it is not intended to limit specific manufacturers or brands. Products from other manufacturers and brands that meet the technical requirements and performance indicators specified in this invention can also meet the application requirements of this invention and are all feasible choices.

[0056] The structural formulas of organic ligand I and organic ligand II used in the following embodiments are shown in the table below:

[0057] Structural formula number of organic ligand I structural Structural formula number of organic ligand II structural Structural Formula 1 Structural Formula 5 Structural Formula 2 Structural Formula 6 Structural Formula 3 Structural Formula 7 Structural Formula 4 Structural Formula 8 Structural Formula 9

[0058] The test methods for the relevant performance indicators in the following embodiments and comparative examples are as follows:

[0059] Specific surface area: The nitrogen adsorption-desorption isotherm was measured using a McASAP2460 analyzer, and the specific surface area of ​​the sample was calculated using the Brunauer-Emmett-Teller method.

[0060] Water contact angle: The water contact angle of the sample was determined using a JY-82B Kruss DSA instrument. Automatic titration was performed using a 16μL drop of pure water, and the water contact angle of the sample was finally measured by the protractor method.

[0061] Zeta potential in aqueous phase: The zeta potential of the sample was tested in accordance with GB / Z 42353-2023 "Guideline for the Determination of Zeta Potential".

[0062] Antibacterial rate against Escherichia coli and Staphylococcus aureus: The antibacterial rate of the sample against Escherichia coli and Staphylococcus aureus was tested in accordance with GB / T 21510-2008 "Test Method for Antibacterial Properties of Nano-Inorganic Materials".

[0063] Example 1

[0064] A method for preparing hydrophilic Co-MOFs-based materials, the synthesis of which is as follows: Figure 1 As shown, the specific steps are as follows:

[0065] (1) Prepare the precursor solution;

[0066] CoCl2, organic ligand I (structural formula 1), and organic ligand II (structural formula 5) were dissolved in DMF to obtain a precursor solution.

[0067] (2) Add methanol, deionized water and trimethylamine to the precursor solution in sequence, and stir magnetically at 20°C for 6 hours to obtain a uniform suspension;

[0068] In steps (1) to (2), the molar ratio of CoCl2, organic ligand I, organic ligand II, deionized water, DMF, methanol and trimethylamine is 1:2.1:1.5:200:200:50:20;

[0069] (3) After centrifuging the suspension to collect the precipitate, it was washed three times with ethanol, and finally dried in a vacuum oven at 40℃ for 12 h to obtain the hydrophilic Co-MOFs-based material. Its 1H NMR spectrum is as follows: Figure 2 As shown, the carbon NMR spectrum is as follows: Figure 3 As shown.

[0070] The final hydrophilic Co-MOF-based material had a specific surface area of ​​1729 m². 2 / g, pore volume 2.3cm 3 / g, pore size of 1.23nm, water contact angle of 20°;

[0071] The zeta potential of hydrophilic Co-MOF-based materials in aqueous phase is -36 mV;

[0072] The hydrophilic Co-MOFs-based material has an antibacterial rate of 99.3% against Escherichia coli and 99.4% against Staphylococcus aureus.

[0073] Example 2

[0074] A method for preparing hydrophilic Co-MOFs-based materials, comprising the following steps:

[0075] (1) Prepare the precursor solution;

[0076] Co(NO3)2, organic ligand I (structural formula 2) and organic ligand II (structural formula 6) were dissolved in DMSO to obtain a precursor solution;

[0077] (2) Ethanol, deionized water and triethylamine were added to the precursor solution in sequence, and the mixture was magnetically stirred at 25°C for 5 hours to obtain a uniform suspension.

[0078] In steps (1) to (2), the molar ratio of Co(NO3)2, organic ligand I, organic ligand II, deionized water, DMSO, ethanol and triethylamine is 1:2.3:1.1:200:100:30:10;

[0079] (3) After centrifuging the suspension to collect the precipitate, it was washed four times with ethanol, and finally dried in a vacuum oven at 50℃ for 8 hours to obtain the hydrophilic Co-MOFs-based material. Its 1H NMR spectrum is as follows: Figure 4 As shown, the carbon NMR spectrum is as follows: Figure 5 As shown.

[0080] The final hydrophilic Co-MOF-based material has a specific surface area of ​​1774 m². 2 / g, pore volume 2.7cm 3 / g, pore size of 1.58nm, water contact angle of 18°;

[0081] The zeta potential of hydrophilic Co-MOF-based materials in aqueous phase is -37 mV;

[0082] The hydrophilic Co-MOFs-based material has an antibacterial rate of 99.4% against Escherichia coli and 99.5% against Staphylococcus aureus.

[0083] Example 3

[0084] A method for preparing hydrophilic Co-MOFs-based materials, comprising the following steps:

[0085] (1) Prepare the precursor solution;

[0086] Co(NO3)2·6H2O, organic ligand I (structural formula 3) and organic ligand II (structural formula 7) were dissolved in DMAc to obtain a precursor solution;

[0087] (2) Add n-propanol, deionized water and tripropylamine to the precursor solution in sequence, and stir magnetically at 30°C for 3 hours to obtain a uniform suspension;

[0088] In steps (1) to (2), the molar ratio of Co(NO3)2·6H2O, organic ligand I, organic ligand II, deionized water, DMAc, n-propanol and tripropylamine is 1:2.2:1.4:100:150:40:15;

[0089] (3) After centrifuging the suspension to collect the precipitate, it was washed five times with ethanol, and finally dried in a vacuum oven at 60℃ for 4 hours to obtain the hydrophilic Co-MOFs-based material. Its 1H NMR spectrum is as follows: Figure 6 As shown, the carbon NMR spectrum is as follows: Figure 7 As shown.

[0090] The final hydrophilic Co-MOF-based material has a specific surface area of ​​1796 m². 2 / g, pore volume 3.2cm 3 / g, pore size of 2.33nm, water contact angle of 16°;

[0091] The zeta potential of hydrophilic Co-MOF-based materials in aqueous phase is -39 mV;

[0092] The hydrophilic Co-MOFs-based material has an antibacterial rate of 99.5% against Escherichia coli and 99.6% against Staphylococcus aureus.

[0093] Example 4

[0094] A method for preparing hydrophilic Co-MOFs-based materials, comprising the following steps:

[0095] (1) Prepare the precursor solution;

[0096] A precursor solution was obtained by dissolving CoSO4·7H2O, organic ligand I (structural formula 4), and organic ligand II (structural formula 8) in DMF.

[0097] (2) Isopropanol, deionized water and trimethylamine were added to the precursor solution in sequence and magnetically stirred at 20°C for 4 hours to obtain a uniform suspension.

[0098] In steps (1) to (2), the molar ratio of CoSO4·7H2O, organic ligand I, organic ligand II, deionized water, DMF, isopropanol and trimethylamine is 1:2.1:1.1:150:100:50:20;

[0099] (3) After centrifuging the suspension to collect the precipitate, it was washed three times with ethanol, and finally dried in a vacuum oven at 45℃ for 10 h to obtain the hydrophilic Co-MOFs-based material. Its 1H NMR spectrum is as follows: Figure 8 As shown, the carbon NMR spectrum is as follows: Figure 9 As shown.

[0100] The specific surface area of ​​the finally prepared hydrophilic Co-MOFs-based material was 1851 m². 2 / g, pore volume 4.1cm 3 / g, pore size of 2.98nm, water contact angle of 14°;

[0101] The zeta potential of hydrophilic Co-MOF-based materials in aqueous phase is -41 mV;

[0102] The hydrophilic Co-MOFs-based material has an antibacterial rate of 99.6% against Escherichia coli and 99.7% against Staphylococcus aureus.

[0103] Example 5

[0104] A method for preparing hydrophilic Co-MOFs-based materials, comprising the following steps:

[0105] (1) Prepare the precursor solution;

[0106] CoSO4, organic ligand I (structural formula 3) and organic ligand II (structural formula 6) were dissolved in DMSO to obtain a precursor solution;

[0107] (2) Ethanol, deionized water and triethylamine were added to the precursor solution in sequence, and the mixture was magnetically stirred at 25°C for 5 hours to obtain a uniform suspension.

[0108] In steps (1) to (2), the molar ratio of CoSO4, organic ligand I, organic ligand II, deionized water, DMSO, ethanol and triethylamine is 1:2.2:1.2:100:150:40:15;

[0109] (3) After centrifuging the suspension to collect the precipitate, it was washed four times with ethanol, and finally dried in a vacuum oven at 53℃ for 9 hours to obtain the hydrophilic Co-MOFs-based material. Its 1H NMR spectrum is as follows: Figure 10 As shown, the carbon NMR spectrum is as follows: Figure 11 As shown.

[0110] The final hydrophilic Co-MOF-based material has a specific surface area of ​​1935 m². 2 / g, pore volume 4.9cm 3 / g, pore size of 3.67nm, water contact angle of 12°;

[0111] The zeta potential of hydrophilic Co-MOF-based materials in aqueous phase is -43 mV;

[0112] The hydrophilic Co-MOFs-based material has an antibacterial rate of 99.6% against Escherichia coli and 99.8% against Staphylococcus aureus.

[0113] Example 6

[0114] A method for preparing hydrophilic Co-MOFs-based materials, comprising the following steps:

[0115] (1) Prepare the precursor solution;

[0116] The precursor solution was obtained by dissolving CoCl2·6H2O, organic ligand I (structural formula 4) and organic ligand II (structural formula 9) in DMAc.

[0117] (2) Isopropanol, deionized water and tripropylamine were added to the precursor solution in sequence and stirred magnetically at 30°C for 4 hours to obtain a uniform suspension.

[0118] In steps (1) to (2), the molar ratio of CoCl2·6H2O, organic ligand I, organic ligand II, deionized water, DMAc, isopropanol and tripropylamine is 1:2.3:1.3:150:200:30:10;

[0119] (3) After centrifuging the suspension to collect the precipitate, it was washed five times with ethanol, and finally dried in a vacuum oven at 58℃ for 6 hours to obtain the hydrophilic Co-MOFs-based material. Its 1H NMR spectrum is as follows: Figure 12 As shown, the carbon NMR spectrum is as follows: Figure 13 As shown.

[0120] The final hydrophilic Co-MOF-based material had a specific surface area of ​​1983 m². 2 / g, pore volume 5.6cm 3 / g, pore size of 4.77nm, water contact angle of 10°;

[0121] The zeta potential of hydrophilic Co-MOF-based materials in aqueous phase is -45 mV;

[0122] The hydrophilic Co-MOFs-based material has an antibacterial rate of 99.7% against Escherichia coli and 99.9% against Staphylococcus aureus.

Claims

1. A method for preparing a hydrophilic Co-MOFs-based material, characterized in that: Organic alcohol, deionized water and organic amine were added sequentially to the precursor solution and mixed to obtain a uniform suspension. The suspension was then centrifuged to collect the precipitate, which was then washed and dried to obtain the hydrophilic Co-MOFs-based material. The precursor solution is obtained by dissolving Co metal salt, organic ligand I, and organic ligand II in an organic solvent; Organic ligand I is , , or ; Organic ligand II is , , , or .

2. The method for preparing a hydrophilic Co-MOFs-based material according to claim 1, characterized in that, Organic alcohols are methanol, ethanol, n-propanol, or isopropanol.

3. The method for preparing a hydrophilic Co-MOFs-based material according to claim 1, characterized in that, The organic amine is trimethylamine, triethylamine, or tripropylamine.

4. The method for preparing a hydrophilic Co-MOFs-based material according to claim 1, characterized in that, Co metal salts are CoCl2, CoCl2·6H2O, Co(NO3)2, Co(NO3)2·6H2O, CoSO4, or CoSO4·7H2O.

5. The method for preparing a hydrophilic Co-MOFs-based material according to claim 1, characterized in that, The organic solvent is DMF, DMSO or DMAc.

6. The method for preparing a hydrophilic Co-MOFs-based material according to claim 1, characterized in that, Washing is performed with ethanol, and the number of washes is 3 to 5; the drying temperature is 40 to 60℃, and the time is 4 to 12 hours.

7. The method for preparing a hydrophilic Co-MOFs-based material according to claim 1, characterized in that, The molar ratio of Co metal salt, organic ligand I, organic ligand II, deionized water, organic solvent, organic alcohol and organic amine is 1:2.1~2.3:1.1~1.5:100~200:100~200:30~50:10~20.

8. The method for preparing a hydrophilic Co-MOFs-based material according to claim 1, characterized in that, The specific surface area of ​​hydrophilic Co-MOFs-based materials is 1729~1983 m². 2 / g, pore volume 2.3~5.6cm 3 / g, pore size 1.23~4.77nm, water contact angle 10°~20°; The zeta potential of hydrophilic Co-MOF-based materials in aqueous phase is -36 to -45 mV; The hydrophilic Co-MOFs-based materials have an antibacterial rate of 99.3-99.7% against Escherichia coli and an antibacterial rate of 99.4-99.9% against Staphylococcus aureus.

Images