Covalent organic framework material, preparation method thereof and application of covalent organic framework material in activating PMS to degrade new pollutants in water body

Abstract

The invention discloses a covalent organic framework material, a preparation method thereof and application of the covalent organic framework material in degrading new pollutants in a water body by activating PMS, the covalent organic framework material contains a pyrene group and a bipyridine linking group, has a flat molecular structure and a laminated nanosheet morphology, and has a regular pore structure; the catalyst has a good crystal structure, reliable mechanical strength and excellent thermal chemical stability and catalytic activity, and is an excellent catalyst; and the subsequent modification and metal atom loading sites exist, so that the possibility is provided for further improving the catalytic activity. The bottleneck problems of low crystallinity and poor stability in the traditional preparation process are solved through solvothermal reaction preparation, use of a mixed solvent system and introduction of a weakly acidic solvent, the preparation method is simple, and large-scale production can be realized. The activated PMS degrades new pollutants in the water body; under the condition that the reaction time is 45 minutes, the degradation rate of the BPA can reach 100%.

Description

Technical Field

[0001] This invention belongs to the field of environmental functional materials and water pollution control technology, specifically relating to a covalent organic framework material and its preparation method, and its application in the degradation of new pollutants in water by activated PMS. Background Technology

[0002] Emerging pollutants refer to organic pollutants that possess characteristics such as biotoxicity, environmental persistence, and bioaccumulation, posing significant risks to the ecological environment or human health, but which are not yet included in environmental management or where existing management measures are inadequate. These pollutants have a wide range of sources, covering multiple industries including chemical, pharmaceutical, and plastics processing. Common emerging pollutants include phenolic derivatives, endocrine disruptors, and emerging drug pollutants. Their residues in water bodies can lead to water quality deterioration, posing a serious threat to aquatic ecosystems and human health.

[0003] Currently, the main methods for treating new pollutants include physical adsorption, biodegradation, and chemical oxidation. While physical adsorption can effectively remove pollutants, the adsorbent materials are difficult to regenerate after saturation and are prone to secondary pollution. Biodegradation is significantly limited by the toxicity of pollutants and environmental conditions, resulting in low treatment efficiency. Traditional chemical oxidation methods (such as Fenton oxidation) require large amounts of chemical reagents, are prone to secondary pollution, and have harsh reaction conditions. Advanced oxidation technologies based on persulfate (PMS) can generate strong oxidizing free radicals (such as sulfate radicals SO4·4·4). - PMS (hydroxyl radicals ·OH) have shown promising potential in the degradation of organic pollutants, but existing catalysts for activating PMS (such as transition metal oxides and carbon-based materials) suffer from problems such as insufficient activity, poor stability, and metal leaching, which limit their large-scale application.

[0004] Covalent organic frameworks (COFs), as a novel type of crystalline porous material, possess advantages such as high specific surface area, tunable pore structure, and abundant functional sites, making them highly promising in the field of catalysis. Extensive literature review reveals limited research on the application of COFs in activating phosphoric acid (PMS) for the degradation of novel pollutants. Therefore, developing efficient, stable, and environmentally friendly PMS-activated COF materials is of great significance for achieving rapid degradation of novel pollutants in water bodies and ensuring aquatic environmental safety. Summary of the Invention

[0005] For the reasons mentioned above, the first objective of this invention is to provide a covalent organic framework material, in which pyrene groups are connected through the 6,6' or 4,4' positions of 2,2' bipyridine to form a COF material. This COF material has a nanosheet morphology formed by flat molecular structure stacking, has a good crystal structure and regular pore structure, and exhibits excellent catalytic activity. Furthermore, the two nitrogen atoms of the bipyridine provide sites for subsequent modification and loading of metal atoms, which provides the possibility for further improving catalytic activity.

[0006] The second objective of this invention is to provide a method for preparing covalent organic framework materials. By using a mixed solvent system and introducing a weakly acidic solvent, the bottleneck problems of low crystallinity and poor stability in the traditional preparation process are solved. The preparation method is simple, does not require complex reaction processes and harsh reaction conditions, and can be prepared on a large scale.

[0007] The third objective of this invention is to provide an application of covalent organic framework material to activate PMS for the degradation of new pollutants in water; under a reaction time of 45 min, the degradation rate of BPA can reach 100%.

[0008] The first objective of this invention can be achieved by adopting the following technical solution:

[0009] A covalent organic framework material having the molecular structure shown in Formula I or Formula II:

[0010]

[0011] The second objective of this invention can be achieved by adopting the following technical solution:

[0012] A method for preparing a covalent organic framework material includes the following steps:

[0013] The covalent organic framework material was prepared by a solvothermal reaction of 1,3,6,8-tetra-(p-aminophenyl)-pyrene with 2,2'-bipyridine-6,6'-dicarboxaldehyde or 2,2'-bipyridine-4,4'-dicarboxaldehyde under vacuum and closed environment.

[0014] Furthermore, the solvent for the solvothermal reaction is an organic solvent; the organic solvent is one or a combination of two or more of methanol, toluene, n-hexane, acetone, 1,2-dichlorobenzene or n-butanol.

[0015] Furthermore, the organic solvent is a composition of 1,2-dichlorobenzene and n-butanol, wherein the volume ratio of 1,2-dichlorobenzene to n-butanol is (0.5-2):1.

[0016] Furthermore, the solvothermal reaction is carried out in the presence of a catalyst, namely acetic acid. Solvent.

[0017] Furthermore, the concentration of the acetic acid is 1-6M; the volume ratio of acetic acid to organic solvent is 1:(5-20).

[0018] Furthermore, the molar ratio of 1,3,6,8-tetra-(p-aminophenyl)-pyrene to 2,2'-bipyridine-6,6'-dicarboxaldehyde or 2,2'-bipyridine-4,4'-dicarboxaldehyde is 1:(2-2.2).

[0019] Furthermore, the molar-volume ratio of 1,3,6,8-tetra-(p-aminophenyl)-pyrene to the organic solvent is 1 mmol:(20-80) mL.

[0020] Furthermore, the reaction conditions are: 100-140℃ for 48-144 hours.

[0021] Furthermore, before the solvothermal reaction, the materials are mixed and then degassed.

[0022] The mixing is carried out under ultrasonic conditions to achieve uniform mixing; the ultrasonic time is 3-5 minutes, and the ultrasonic temperature is 26-30℃.

[0023] The degassing process involves 2-5 cycles of liquid nitrogen freezing-thawing.

[0024] Furthermore, it also includes post-processing steps: after the solvothermal reaction ends, cooling is performed, solid-liquid separation is carried out, and the solid product is washed with at least one of N,N-dimethylformamide, methanol, acetone, and tetrahydrofuran; then it is dried.

[0025] The third objective of this invention can be achieved by adopting the following technical solution:

[0026] The above-mentioned covalent organic framework materials are used in the activation of PMS to degrade new pollutants in water.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0028] 1. The covalent organic framework material of this application has a pyrene group and a bipyridine linking group. The pyrene group is linked to the 6,6' or 4,4' position of the 2,2' bipyridine, which gives the COF material a flat molecular structure and a stacked nanosheet morphology with a regular porous structure. The covalent organic framework material of this application has a good crystal structure, reliable mechanical strength, excellent thermochemical stability and catalytic activity, and is an excellent catalyst. In addition, the two nitrogen atoms of the bipyridine provide sites for subsequent modification and loading of metal atoms, which provides the possibility for further improving the catalytic activity.

[0029] 2. The preparation method of the covalent organic framework material of this application solves the bottleneck problems of low crystallinity and poor stability in the traditional preparation process by using a mixed solvent system and introducing a weakly acidic solvent. The preparation method is simple. The process uses inexpensive monomers, which significantly reduces production costs. The reaction process is low-pollution and easy to recycle, showing excellent social, economic and ecological value, and can be produced on a large scale.

[0030] 3. The covalent organic framework material of this application activates PMS to degrade new pollutants in water; under the condition of a reaction time of 45 min, the degradation rate of BPA can reach 100%. Attached Figure Description

[0031] Figure 1 Chemical structure diagram of 6DAPy-COFs prepared in Example 1;

[0032] Figure 2 The chemical structure diagram of the 4DAPy-COFs prepared in Example 2;

[0033] Figure 3 SEM image of 6DAPy-COFs prepared in Example 1;

[0034] Figure 4 XRD image of 6DAPy-COFs prepared in Example 1;

[0035] Figure 5 XRD image of 4DAPy-COFs prepared in Example 2;

[0036] Figure 6 The FT-IR spectrum of 6DAPy-COFs prepared in Example 1;

[0037] Figure 7 The graph shows the adsorption results of BPA on 6DAPy-COFs prepared in Example 1 and 4DAPy-COFs prepared in Example 2.

[0038] Figure 8 The graph shows the removal rate of BPA by activated PMS using 6DAPy-COFs prepared in Example 1 and 4DAPy-COFs prepared in Example 2.

[0039] Figure 9 The 6DAPy-COFs prepared in Example 1 degraded the K of pollutants at different pH values. obs Value diagram;

[0040] Figure 10 This is an XRD image of the 6DAPy-COFs-activated PMS after BPA degradation reaction prepared in Example 1. Detailed Implementation

[0041] The technical solution of the present invention will now be clearly and completely described with reference to specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0042] The preparation of covalent organic framework materials faces technical bottlenecks such as difficulty in controlling crystallinity, insufficient chemical stability, and limitations in functionalization and large-scale production. Meanwhile, current technologies for treating new pollutants suffer from low efficiency, poor stability, and a tendency to generate secondary pollution. Since covalent organic framework materials possess catalytic activity, this invention utilizes covalent organic framework materials to activate PMS for the degradation of new pollutants in water bodies. Furthermore, the optimal PMS activation reaction system parameters were determined to achieve efficient, stable, and environmentally friendly degradation of new pollutants in water bodies.

[0043] A covalent organic framework material having the molecular structure shown in Formula I or Formula II:

[0044]

[0045] The covalent organic framework material of this application contains a pyrene group and a bipyridine linker group. The pyrene group is a fused-ring aromatic hydrocarbon, which consists of four linearly fused benzene rings forming a planar conjugated structure with a highly delocalized π-electron system. It forms a larger conjugated structure with the benzene ring, imine, and bipyridine, which makes the covalent organic framework material catalytically active. It also has high stability, good crystal structure, reliable mechanical strength, and excellent thermochemical stability.

[0046] The pyrene group is attached to the 6,6' or 4,4' position of 2,2' bipyridine, which gives the COF material a flat molecular structure and a stacked nanosheet morphology with a regular porous structure. Furthermore, by adjusting the position of the pyridine nitrogen atom on different positions of the bipyridine, different catalytic activities and potential modification activities are exhibited.

[0047] This application also provides a method for preparing a covalent organic framework material, comprising the following steps:

[0048] The covalent organic framework material was prepared by a solvothermal reaction of 1,3,6,8-tetra-(p-aminophenyl)-pyrene with 2,2'-bipyridine-6,6'-dicarboxaldehyde or 2,2'-bipyridine-4,4'-dicarboxaldehyde under vacuum and closed environment.

[0049] Solvothermal reaction is a green, efficient and scalable preparation method, and the monomer 1,3,6,8-tetra-(p-aminophenyl)-pyrene is a raw material with simple sources and wide applications. Therefore, the preparation method of this application does not rely on complex equipment, and the preparation process is simple and clear. At the same time, the process uses inexpensive monomers, which significantly reduces production costs. The reaction process is low-pollution and easy to recycle, showing excellent social, economic and ecological value, and can be produced on a large scale.

[0050] In one embodiment, the solvent for the solvothermal reaction is an organic solvent; the organic solvent is one or a combination of two or more of methanol, toluene, n-hexane, acetone, 1,2-dichlorobenzene or n-butanol.

[0051] In one embodiment, the organic solvent is a composition of 1,2-dichlorobenzene and n-butanol, wherein the volume ratio of 1,2-dichlorobenzene to n-butanol is (0.5-2):1.

[0052] In one embodiment, the solvothermal reaction is carried out in the presence of a catalyst, which is acetic acid solvent.

[0053] In one embodiment, the concentration of acetic acid is 1-6M; the volume ratio of acetic acid to organic solvent is 1:(5-20). This application solves the bottleneck problems of low crystallinity and poor stability in the traditional preparation process by using a mixed solvent system and introducing a weakly acidic solution as a catalyst.

[0054] In one embodiment, the molar ratio of 1,3,6,8-tetra-(p-aminophenyl)-pyrene to 2,2'-bipyridine-6,6'-dicarboxaldehyde or 2,2'-bipyridine-4,4'-dicarboxaldehyde is 1:(2-2.2).

[0055] In one embodiment, the molar-volume ratio of 1,3,6,8-tetra-(p-aminophenyl)-pyrene to the organic solvent is 1 mmol:(20-80) mL.

[0056] As one implementation method, the reaction conditions are: 100-140℃ for 48-144 hours.

[0057] As one implementation method, the materials are mixed and degassed before the solvothermal reaction.

[0058] In one implementation, the system reacts in a glass tube. First, the mixture is dispersed evenly, degassed by a freeze-thaw cycle, and the glass tube is sealed with a torch flame before a high-temperature solvothermal reaction is carried out.

[0059] As one embodiment, the mixing is carried out under ultrasonic conditions to achieve uniform mixing; the ultrasonic time is 3-5 minutes and the ultrasonic temperature is 26-30℃.

[0060] As one implementation method, the degassing is performed by using liquid nitrogen freezing-thawing cycles 2-5 times.

[0061] As one embodiment, the method also includes a post-processing step: after the solvothermal reaction ends, the product is cooled, solid-liquid separation is performed, and the solid product is washed with at least one of N,N-dimethylformamide, methanol, acetone, and tetrahydrofuran; then it is dried.

[0062] As one implementation method, solid-liquid separation is performed by centrifugation; the centrifugation is carried out using a high-speed centrifuge with a rotation speed of 8000-15000 r / min and a time of 2-10 min.

[0063] This application provides the application of the aforementioned covalent organic framework material in the degradation of new pollutants in water by activated PMS.

[0064] The following provides a further explanation using specific implementation methods.

[0065] Example 1

[0066] 0.02 mmol of 1,3,6,8-tetra-(p-aminophenyl)pyrene and 0.04 mmol of 2,2'-bipyridine-6,6'-dicarboxaldehyde were added to a 10 mL glass tube. 0.5 mL of 1,2-dichlorobenzene, 0.5 mL of n-butanol, and 0.1 mL of 6M acetic acid were added to the mixture. The glass tube was sonicated for 5 min to ensure homogeneity, followed by three cycles of liquid nitrogen freezing and thawing to remove oxygen. The tube was then quickly sealed with a flame gun and heated to 120°C in an oven for 72 h. A solid substance formed at the bottom of the tube. The product was recovered by centrifugation and washed three times (3 × 20 mL) with N,N-dimethylformamide (DMF), followed by drying to obtain a covalent organic framework material named 6DAPy-COFs. The structure is shown below. Figure 1 As shown.

[0067] Example 2

[0068] 0.02 mmol of 1,3,6,8-tetra-(p-aminophenyl)pyrene and 0.042 mmol of 2,2'-bipyridine-6,6'-dicarboxaldehyde were placed in a 10 mL glass tube. 0.2 mL of toluene, 0.2 mL of n-butanol, and 0.08 mL of 6M acetic acid were added to the mixture. The glass tube was sonicated for 5 min to ensure homogeneity. Then, the tube was degassed using a liquid nitrogen freeze-thaw cycle three times to remove oxygen. The tube was then quickly sealed with a flame gun and heated to 100°C in an oven for 144 h. A solid substance formed at the bottom of the tube was collected by centrifugation. The product was washed three times (3 × 20 mL) with N,N-dimethylformamide (DMF) and then dried to obtain a covalent organic framework material, named 6DAPy-COFs.

[0069] Example 3

[0070] 0.02 mmol of 1,3,6,8-tetra-(p-aminophenyl)pyrene and 0.04 mmol of 2,2'-bipyridine-4,4'-dicarboxaldehyde were added to a 10 mL glass tube. 0.5 mL of 1,2-dichlorobenzene, 0.5 mL of n-butanol, and 0.1 mL of 6M acetic acid were added to the mixture. The glass tube was sonicated for 5 min to ensure homogeneity, followed by three cycles of liquid nitrogen freezing and thawing to remove oxygen. The tube was then quickly sealed with a flame gun and heated to 120°C in an oven for 72 h. A solid substance formed at the bottom of the tube. The product was recovered by centrifugation and washed three times (3 × 20 mL) with N,N-dimethylformamide (DMF), followed by drying to obtain a covalent organic framework material named 4DAPy-COFs. The structure is shown below. Figure 2 As shown.

[0071] Example 4

[0072] 0.02 mmol of 1,3,6,8-tetra-(p-aminophenyl)pyrene and 0.044 mmol of 2,2'-bipyridine-4,4'-dicarboxaldehyde were placed in a 10 mL glass tube. 0.8 mL of 1,2-dichlorobenzene, 0.8 mL of methanol, and 0.08 mL of 6M acetic acid were added to the mixture. The glass tube was then sonicated for 5 min to ensure homogeneity. Subsequently, the tube was degassed using a liquid nitrogen freeze-thaw cycle three times to thoroughly remove oxygen. The tube was then quickly sealed with a flame gun and heated to 140 °C in an oven for 48 h. A solid substance formed at the bottom of the tube was collected by centrifugation. The product was washed three times (3 × 20 mL) with N,N-dimethylformamide (DMF) and then dried to obtain a covalent organic framework material, named 4DAPy-COFs.

[0073] Material characterization:

[0074] (1) The 6DAPy-COFs prepared in Example 1 were subjected to scanning electron microscopy (SEM). The SEM images are shown below. Figure 3 As shown.

[0075] from Figure 3 As can be seen, the covalent organic framework material 6DAPy-COFs has a nanosheet morphology.

[0076] (2) X-ray diffraction analysis was performed on the 6DAPy-COFs prepared in Example 1 and the 4DAPy-COFs prepared in Example 3. The X-ray diffraction patterns are shown below. Figure 4 and Figure 5 As shown.

[0077] pass Figure 4 and Figure 5 The sharp diffraction peaks indicate that both 6DAPy-COFs and 4DAPy-COFs have good crystal structures.

[0078] (3) The 6DAPy-COFs prepared in Example 1 were subjected to infrared spectroscopy testing, and the results are as follows: Figure 6 As shown.

[0079] Figure 6 In the middle, TPy is 1690cm -1 The C=O peak at 1620 cm⁻¹ almost disappears in 6DAPy-COFs, while it remains at 1620 cm⁻¹ in 6DAPy-COFs. -1 The presence of a C=N peak indicates that the formaldehyde group in bipyridine reacted with the amino group in pyrene to form COF.

[0080] (4) BPA adsorption test

[0081] 2 mg of 6DAPy-COFs and 4DAPy-COFs were weighed and placed separately in quartz reactors. 25 mL of BPA solution (concentration 10 mg / L) was added to each reactor. A 1 mL water sample was then taken from each reactor using a syringe and filtered through a 0.22 μm polytetrafluoroethylene (PTFE) filter as the 0 min sample. Subsequently, 1 mL samples were taken at 5, 10, 15, 20, and 30 min and filtered. Finally, the BPA content was measured using liquid chromatography. The results are as follows: Figure 7 As shown.

[0082] from Figure 7 As can be seen, neither 6DAPy-COFs nor 4DAPy-COFs has a significant adsorption effect on pollutants, and 15 min is taken as the adsorption equilibrium time for the two materials.

[0083] (5) Activated PMS pollutant degradation test

[0084] 2 mg of 6DAPy-COFs and 4DAPy-COFs were weighed and placed separately in quartz reactors. 25 mL of BPA solution (10 mg / L) was added to each reactor. The reaction was allowed to proceed in the dark for 15 min. At this point, 1 mL of water sample was taken from the quartz reactor using a syringe and filtered through a 0.22 μm polytetrafluoroethylene (PTFE) filter as the 0 min sample. Subsequently, PMS (2 mM) was added to initiate the reaction. 1 mL samples were taken at 1, 3, 5, 10, 15, 20, 30, and 45 min and filtered. Finally, the BPA content was measured using liquid chromatography. The results are as follows: Figure 8 As shown.

[0085] Under the conditions of 0.08 g / L 6DAPy-COFs dosage, 2 mM PMS concentration, and 45 min reaction time, the degradation rate of BPA can reach 100%. In contrast, the degradation performance of 4DAPy-COFs is significantly lower than that of 6DAPy-COFs. Under the same conditions, only about 70% of the pollutants can be degraded in 45 min.

[0086] (6) Performance of decontamination at different pH values

[0087] 2 mg of 6DAPy-COFs was weighed and placed in a quartz reactor. 25 mL of BPA solution (10 mg / L) was added, and five parallel reactions were performed, adjusting the pH to 3, 5, 7, 9, and 11 respectively. The reaction was carried out in the dark for 15 min. At this point, 1 mL of water sample was taken from the quartz reactor using a syringe and filtered through a 0.22 μm polytetrafluoroethylene (PTFE) filter as the 0 min sample. Subsequently, PMS (to a concentration of 2 mM) was added to start the reaction. 1 mL samples were taken at 1, 3, 5, 10, 15, 20, 30, and 45 min and filtered. Finally, the BPA content was measured using liquid chromatography. The results are as follows: Figure 9 As shown.

[0088] like Figure 9 As shown, the performance of 6DAPy-COFs in degrading pollutants remained almost unchanged at different pH values, and at pH 7, K obs The highest value reached 0.056 min. -1 This demonstrates its excellent versatility in pollutant degradation.

[0089] (7) Stability test

[0090] The reaction solution after PMS degradation in (5) was centrifuged, and the solid precipitate was collected. It was then washed three times (3 × 20 mL) with N,N-dimethylformamide (DMF), dried, and subjected to X-ray diffraction analysis. The X-ray diffraction pattern is shown below. Figure 10 As shown.

[0091] from Figure 10 It can be seen that the 6DAPy-COFs material retains its crystallinity after the reaction, and Figure 10 X-ray diffraction peaks and Figure 4 The diffraction peaks showed no significant difference, proving that 6DAPy-COFs have good stability.

[0092] In summary, this application constructs 6DAPy-COFs and 4DAPy-COFs with nanosheet morphology using pyrene and bipyridine as units through different linkage sites, forming covalent organic framework materials with excellent catalytic activation of PMS, thus enabling PMS to exhibit superior catalytic degradation of the novel pollutant BPA. Through coordination environment regulation, selective degradation of the novel pollutant is achieved, with a 100% degradation rate of phenolic derivatives reaching within 45 minutes, realizing highly efficient targeted removal of the novel pollutant. This fills the technological gap in the precise treatment of novel water pollutants.

[0093] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A covalent organic framework material, characterized in that, Having the molecular structure shown in Formula I or Formula II:

2. The method for preparing the covalent organic framework material according to claim 1, characterized in that, Includes the following steps: The covalent organic framework material was prepared by a solvothermal reaction of 1,3,6,8-tetra-(p-aminophenyl)-pyrene with 2,2'-bipyridine-6,6'-dicarboxaldehyde or 2,2'-bipyridine-4,4'-dicarboxaldehyde under vacuum and closed environment.

3. The method for preparing the covalent organic framework material according to claim 2, characterized in that, The solvent for the solvothermal reaction is an organic solvent; the organic solvent is one or a combination of two or more of methanol, toluene, n-hexane, acetone, 1,2-dichlorobenzene or n-butanol; preferably, the organic solvent is a combination of 1,2-dichlorobenzene and n-butanol, and the volume ratio of 1,2-dichlorobenzene to n-butanol is (0.5-2):

1.

4. The method for preparing the covalent organic framework material according to claim 2, characterized in that, The solvothermal reaction is carried out in the presence of a catalyst, which is acetic acid solvent; preferably, the concentration of the acetic acid is 1-6M; and the volume ratio of acetic acid to organic solvent is 1:(5-20).

5. The method for preparing the covalent organic framework material according to claim 2, characterized in that, The molar ratio of 1,3,6,8-tetra-(p-aminophenyl)-pyrene to 2,2'-bipyridine-6,6'-dicarboxaldehyde or 2,2'-bipyridine-4,4'-dicarboxaldehyde is 1:(2-2.2).

6. The method for preparing the covalent organic framework material according to claim 2, characterized in that, The molar-volume ratio of 1,3,6,8-tetra-(p-aminophenyl)-pyrene to the organic solvent was 1 mmol:(20-80) mL.

7. The method for preparing the covalent organic framework material according to claim 2, characterized in that, The reaction conditions are: 100-140℃ for 48-144 hours.

8. The method for preparing the covalent organic framework material according to claim 2, characterized in that, Before the solvothermal reaction, the materials are mixed and then degassed. The mixing is carried out under ultrasonic conditions to achieve uniform mixing; the ultrasonic time is 3-5 minutes, and the ultrasonic temperature is 26-30℃. The degassing process involves 2-5 cycles of liquid nitrogen freezing-thawing.

9. The method for preparing the covalent organic framework material according to claim 2, characterized in that, It also includes post-processing steps: after the solvothermal reaction ends, cooling is performed, solid-liquid separation is carried out, and the solid product is washed with at least one of N,N-dimethylformamide, methanol, acetone, and tetrahydrofuran; then it is dried.

10. The application of the covalent organic framework material according to claim 1, or the covalent organic framework material prepared by the preparation method of any one of claims 2-9, in the degradation of new pollutants in water by activated PMS.

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