Fluorinated covalent organic framework materials, methods of making, and applications in photocatalytic production of hydrogen peroxide

Abstract

The application discloses a fluorinated covalent organic framework material, a preparation method thereof and application thereof in photocatalytic production of H2O2, and the fluorinated covalent organic framework material is prepared through an aldehyde-amine condensation reaction of fluorinated phenyl (p) diamine and functionalized benzene-1,3,5-tricarboxaldehyde. Under a laboratory light source and natural sunlight, the fluorinated covalent organic framework material has excellent photocatalytic H2O2 production capacity in a pure water system, and has high activity and selectivity.

Description

Technical Field

[0001] This invention relates to the field of functional materials technology, and in particular to fluorinated covalent organic framework materials, their preparation methods, and their application in the photocatalytic production of hydrogen peroxide. Background Technology

[0002] Since its initial discovery in 1818 through the reaction of barium peroxide and nitric acid, hydrogen peroxide (H₂O₂) has attracted increasing attention worldwide due to its versatility. As a clean and mild oxidant, H₂O₂ possesses numerous advantages, such as the highest reactive oxygen species content, excellent effectiveness over a wide pH range, and the absence of toxic byproducts in the reaction (producing only water / oxygen). H₂O₂ is widely used as a multifunctional reagent in various industrial fields, including bleaching, mining and metal processing, detergent applications, wastewater treatment, and chemical organic synthesis.

[0003] Recently, it has been reported that H2O2 is an ideal energy carrier for single-component fuel cell power generation. Compared with hydrogen (1.23V) or methanol (1.21V) fuel cells, H2O2 exhibits a lower output potential (1.09V). In addition, it has perfect solubility in water, making it easy to store and transport.

[0004] Currently, common methods for producing H2O2 include anthraquinone oxidation, electrochemical synthesis, and noble metal catalysis. However, these methods are complex, have high process requirements, and are costly. Therefore, developing an environmentally friendly and cost-effective H2O2 production route is crucial. One alternative method is to produce H2O2 through the direct reaction of H2 and O2 in the presence of a noble metal catalyst (e.g., Pd, Pt, and PdAu). This reaction involves passing H2 and O2 gases into an acidic methanol solvent, where they react to produce H2O2 at near-0°C with the aid of a catalyst. However, due to the high risk of explosion and the high cost of noble metal catalysts, this method remains less than ideal. Photocatalysis is a forward-looking technology that converts solar energy into chemical substances. Utilizing abundant natural water and oxygen from the air as raw materials, and sunlight as the energy input, photocatalytic synthesis of H2O2 is achieved. This method does not use sacrificial agents and is considered one of the green and sustainable methods.

[0005] Various photocatalysts have been synthesized and explored in H2O2 production, including inorganic semiconductors (such as TiO2, ZnO, and BiVO4), carbon materials (such as graphene, carbon oxides, and polycarbon nitride (PCN)), conjugated photocatalyst polymers, resorcinol-formaldehyde resins, and metal-organic frameworks (MOFs). Organic polymer photocatalysts, in particular, have received close attention since g-C3N4 was first used in H2O2 production in 2014. Unlike inorganic semiconductors, organic polymer photocatalysts exhibit several advantages, such as being composed of abundant Earth elements (such as C, N, O, and H), generating long-lived charge carriers, forming suitable intermediates for H2O2 production, and exhibiting low H2O2 decomposition rates. However, organic polymer semiconductors still face some challenges in photocatalysis, such as low crystallinity, weak visible light absorption, poor separation of photogenerated charge carriers, and a lack of structural diversity, resulting in relatively poor photocatalytic performance. To overcome these bottlenecks in organic polymer photocatalysts, covalent organic frameworks (COFs) have emerged as an emerging candidate material for H2O2 production. Due to their tunable structure, excellent sunlight collection and carrier separation capabilities, combined with other unique intrinsic properties such as structural regularity, robust framework, inherent porosity, abundant surface area, and chemical stability, COFs show great potential in photocatalytic energy conversion and environmental remediation. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing catalysts for H2O2 production by providing a fluorinated covalent organic framework material that enables efficient, green, and low-cost photocatalytic H2O2 production.

[0007] Another objective of this invention is to provide a method for preparing the fluorinated covalent organic framework material. Specifically, the fluorinated covalent organic framework material is prepared by an aldehyde-amine condensation reaction of fluorinated phenyl (p)diamine and functionalized trimesin. This synthesis process is simple and convenient to operate.

[0008] Another objective of this invention is to provide the application of the fluorinated covalent organic framework material in the photocatalytic production of H2O2. Under laboratory light sources and natural sunlight, the fluorinated covalent organic framework material of this invention exhibits excellent photocatalytic H2O2 production capability in a pure water system, demonstrating high activity and selectivity.

[0009] The technical solution adopted to achieve the purpose of this invention is:

[0010] Fluorinated covalent organic framework materials have the following structural formula:

[0011]

[0012] Where: n is 1 or 2;

[0013] R1, R2, R3, or R4 are H, F, CF3, or CH3;

[0014] R5, R6, or R7 are H, OH, Cl, or Br.

[0015] In the above technical solution, the method for synthesizing the fluorinated covalent organic framework material includes the following steps:

[0016] Fluorophenylenediamine and functionalized pyromellitic methyl ester with a molar ratio of 6:5-2:1 were added to a reaction vessel, and then a solvent was added to dissolve the solid powder completely. The reaction vessel was evacuated under a freezing environment and reacted at 100-180°C for 24-80 hours. After the reaction was complete, the product was cooled to room temperature, washed, centrifuged, and vacuum dried to obtain the fluorinated covalent organic framework material.

[0017] The fluorophenylenediamine has one or more of the following structural formulas:

[0018]

[0019] The functionalized pyromellitic aldehyde has one or more of the following structural formulas:

[0020]

[0021] In the above technical solution, the solvent is a chlorobenzene solvent and an alcohol solvent.

[0022] In the above technical solution, furan-based solvents are used for repeated washing during the washing process.

[0023] In the above technical solution, the vacuum drying temperature is 50-100℃ and the time is 12-48h.

[0024] Another aspect of the present invention includes the application of the aforementioned fluorinated covalent organic framework material in the photocatalytic production of hydrogen peroxide.

[0025] In the above technical solution, under pure oxygen or air conditions, using the fluorinated covalent organic framework material as a catalyst and water as the reaction system solution, a catalytic reaction is carried out under natural light or xenon lamp irradiation to prepare H2O2.

[0026] In the above technical solution, the mass ratio of catalyst to water is not less than 1:6.

[0027] In the above technical solution, when the structural formula of the fluorinated covalent organic framework material is as follows:

[0028]

[0029] Under xenon lamp irradiation in pure oxygen conditions, the concentration of hydrogen peroxide produced is greater than 400 μM, and the rate of H2O2 production is greater than 4 mmol g. -1 h -1 .

[0030] In the above technical solution, when the structural formula of the fluorinated covalent organic framework material is as follows:

[0031]

[0032] Under xenon lamp irradiation in air, the concentration of hydrogen peroxide generated is greater than 300 μM, and the rate of H2O2 production is greater than 3 mmol g. -1 h -1 .

[0033] Compared with the prior art, the beneficial effects of the present invention are:

[0034] 1. The fluorinated covalent organic framework material constructed in this invention is obtained through the aldehyde-amine condensation reaction of fluorinated phenylene(p)diamine (p-phenylenediamine) and functionalized trimesin. Under light-driven conditions, it exhibits excellent photocatalytic oxygen reduction performance in pure oxygen, and retains approximately 70% of the performance under pure oxygen conditions in air.

[0035] 2. Compared with the prior art, the method for preparing fluorinated covalent organic framework materials provided by the present invention is simple to operate, has excellent photocatalytic performance, and is conducive to the recycling of catalysts, thus possessing excellent potential for practical commercial application.

[0036] 3. The catalytic reaction system of fluorinated covalent organic framework materials is pure water, which has the characteristics of green, pollution-free and low cost. Attached Figure Description

[0037] Figure 1a This is the synthetic route diagram for F-COF-1.

[0038] Figure 1b This is the synthetic route diagram for F-COF-2.

[0039] Figure 1c This is the synthetic route diagram for F-COF-3.

[0040] Figure 2 This is a powder X-ray diffraction pattern of F-COF-1.

[0041] Figure 3 This is the Fourier transform infrared spectrum of F-COF-1.

[0042] Figure 4 This is a scanning electron microscope image of F-COF-1.

[0043] Figure 5This is an energy-dispersive X-ray spectroscopy (EDS) analysis of F-COF-1 using ultra-high resolution field transmission electron microscopy.

[0044] Figure 6 This is a comparison chart of the photoreduction rates of O2 products and air by F-COF-1 as a catalyst.

[0045] Figure 7 This is a powder X-ray diffraction pattern of F-COF-2.

[0046] Figure 8 This is the Fourier transform infrared spectrum of F-COF-2.

[0047] Figure 9 This is a scanning electron microscope image of F-COF-2.

[0048] Figure 10 This is an energy-dispersive X-ray spectroscopy (EDS) analysis of F-COF-2 using a high-resolution field transmission electron microscope.

[0049] Figure 11 This is a comparison chart of the photoreduction rates of O2 products and air as a catalyst using F-COF-2.

[0050] Figure 12 This is a powder X-ray diffraction pattern of F-COF-3.

[0051] Figure 13 This is the Fourier transform infrared spectrum of F-COF-3.

[0052] Figure 14 This is a scanning electron microscope image of F-COF-3.

[0053] Figure 15 This is an energy-dispersive X-ray spectroscopy (EDS) analysis of F-COF-3 using a high-resolution field transmission electron microscope.

[0054] Figure 16 This is a comparison chart of the photoreduction rates of O2 products and air using F-COF-3 as a catalyst. Detailed Implementation

[0055] The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0056] Example 1

[0057] like Figure 1a As shown, the fluorinated covalent organic framework material (F-COF-1) is mainly synthesized from fluorinated phenyl(p)diamine 1 and functionalized pyromellitic methyl ether 1 via a Schiff base reaction of aldehyde-amine condensation. The two are linked by covalent bonds. Specifically, it is prepared by the following method:

[0058] Accurately weighed fluorophenyl(p)diamine 1 and functionalized trimesoaldehyde were placed in a heat-resistant glass tube. Chlorobenzene solvent and then alcohol solvent were added sequentially to the glass tube, and the mixture was sonicated until the solid powder was completely dissolved. The tube was then evacuated under liquid nitrogen conditions using a vacuum pump, and the tube was sealed after evacuation. The reaction mixture was then placed in an oven and heated at 100-180°C for 24-80 hours.

[0059] Finally, the reactants were cooled to room temperature, and the reactants were repeatedly washed and centrifuged with furan solvents until the supernatant was colorless. The supernatant was then dried under vacuum to obtain a solid powder fluorinated covalent organic framework material (F-COF-1).

[0060] Structural analysis was performed on the fluorinated covalent organic framework material (F-COF-1) prepared above, and the results were as follows: Figure 2-5 The results shown; by Figure 2 It can be seen that the fluorinated covalent organic framework material (F-COF-1) has sharp diffraction peaks, indicating that it is a highly crystalline framework material. From... Figure 3 It can be seen that the reactant fluorine ligands are at 3450 cm⁻¹ -1 There is a distinct double peak characteristic of -NH2 at 1644 cm⁻¹, and the functionalized phenyltrialdehyde reactant shows a peak characteristic of -NH2 at 1644 cm⁻¹. -1 A stretching vibration of -C=H exists at this point. Fluorinated covalent organic framework materials (F-COF-1) do not exhibit the aforementioned characteristic absorption peak, only showing one at 1620 cm⁻¹. -1 The position shows a characteristic absorption peak of -C=N-, thus proving the successful synthesis of the fluorinated covalent organic framework material (F-COF-1).

[0061] Morphological analysis was performed on the fluorinated covalent organic framework material (F-COF-1) prepared above, and the results were as follows: Figure 4-5 The results shown; by Figure 4 It is known that the fluorinated covalent organic framework material (F-COF-1) has a sheet-like structure, providing further evidence for its successful preparation. For example... Figure 5 As shown, in order to investigate the corresponding distribution of each element, energy-dispersive X-ray spectroscopy analysis was performed on the fluorinated covalent organic framework material (F-COF-1) to determine the elemental distribution. The results showed that C, N, O and F elements were uniformly distributed in the fluorinated covalent organic framework (F-COF-1) catalytic material.

[0062] Example 2

[0063] The application of fluorinated covalent organic framework material (F-COF-1) in the photocatalytic production of hydrogen peroxide specifically includes the following steps:

[0064] The oxygen reduction reaction, catalyzed by F-COF-1, occurs in a quartz tube. The fluorinated covalent organic framework material (F-COF-1) serves as the catalyst, water is the reaction solution, and a light intensity of 1500 mW / cm² is used. -2 A xenon lamp was used as the irradiation light source. During the catalytic process, the temperature of the space where the quartz tube was located was maintained at 25°C. Before the catalytic reaction started, O2 was introduced into the reactor to remove CO2 and other gases. After the reaction was completed, the concentration of the liquid product produced in the experiment was detected by a colorimetric method using an ultraviolet spectrophotometer.

[0065] Example 3

[0066] The application of fluorinated covalent organic framework material (F-COF-1) in the photocatalytic production of hydrogen peroxide specifically includes the following steps:

[0067] The oxygen reduction reaction, catalyzed by F-COF-1, occurred in a quartz tube. The covalent organic framework material F-COF-1 served as the catalyst, and water was used as the reaction solution. A light intensity of 1500 mW / cm² was employed. -2 A xenon lamp was used as the irradiation light source. During the catalytic process, the temperature of the space where the quartz tube was located was maintained at 25°C. Before the catalytic reaction started, air was introduced into the reactor. After the reaction was completed, the concentration of the liquid product produced in the experiment was detected by a colorimetric method using an ultraviolet spectrophotometer.

[0068] Combining Examples 2 and 3, by Figure 6 It can be seen that, under pure oxygen conditions, the highest rate of photoreduction of O2 to H2O2 by the fluorinated covalent organic framework material (F-COF-1) is greater than 4 mmol g. -1 h -1 Under air conditions, the highest rate of photoreduction of air to produce H2O2 is greater than 3 mmol g. -1 h -1 The results showed that fluorinated covalent organic framework material (F-COF-1) has the advantages of high efficiency, greenness, and low cost in photoreduction of O2 and H2O2 production from air as a catalyst.

[0069] Example 4

[0070] like Figure 1b As shown, the fluorinated covalent organic framework material (F-COF-2) is mainly synthesized from fluorinated phenyl(p)diamine 2 and functionalized trimesin 2 via a Schiff base reaction of aldehyde-amine condensation. The two are linked by covalent bonds. Specifically, it is prepared by the following method:

[0071] Accurately weighed fluorophenyl(p)diamine 2 and functionalized trimesoaldehyde were placed in a heat-resistant glass tube. Chlorobenzene solvent and then alcohol solvent were added sequentially to the glass tube, and the mixture was sonicated until the solid powder was completely dissolved. The tube was then evacuated under liquid nitrogen conditions using a vacuum pump, and the tube was sealed after evacuation. The reaction mixture was then placed in an oven and heated at 100-180°C for 24-80 hours.

[0072] Finally, the reactants were cooled to room temperature, and the reactants were repeatedly washed and centrifuged with furan solvents until the supernatant was colorless. The supernatant was then dried under vacuum to obtain a solid powder fluorinated covalent organic framework material (F-COF-2).

[0073] Structural analysis was performed on the fluorinated covalent organic framework material (F-COF-2) prepared above, and the results were as follows: Figure 7-10 The results shown; by Figure 7 It can be seen that the fluorinated covalent organic framework material (F-COF-2) has sharp diffraction peaks, indicating that it is a highly crystalline framework material. From... Figure 8 It can be seen that the reactant fluorine ligands are at 3450 cm⁻¹ -1 There is a distinct double peak characteristic of -NH2 at 1644 cm⁻¹, and the functionalized phenyltrialdehyde reactant shows a peak characteristic of -NH2 at 1644 cm⁻¹. -1 A stretching vibration of -C=H exists at this point. Fluorinated covalent organic framework materials (F-COF-2) do not exhibit the aforementioned characteristic absorption peak, only showing one at 1620 cm⁻¹. -1 The position shows a characteristic absorption peak of -C=N-, thus proving the successful synthesis of the fluorinated covalent organic framework material (F-COF-2).

[0074] Morphological analysis was performed on the fluorinated covalent organic framework material (F-COF-2) prepared above, and the results were as follows: Figure 9-10 The results shown; by Figure 9 It is known that the fluorinated covalent organic framework material (F-COF-2) has a sheet-like structure, providing further evidence for its successful preparation. For example... Figure 10 As shown, in order to investigate the corresponding distribution of each element, energy-dispersive X-ray spectroscopy analysis was performed on the fluorinated covalent organic framework material (F-COF-2) to determine the elemental distribution. The results showed that C, N, O and F elements were uniformly distributed in the fluorinated covalent organic framework (F-COF-2) catalytic material.

[0075] Example 5

[0076] The application of fluorinated covalent organic framework materials (F-COF-2) in the photocatalytic production of hydrogen peroxide specifically includes the following steps:

[0077] The oxygen reduction reaction occurs in a quartz tube, with F-COF-2 as the catalyst and water as the reaction solution. The light intensity used is 1500 mW / cm². -2 A xenon lamp was used as the irradiation light source. During the catalytic process, the temperature of the space where the quartz tube was located was maintained at 25°C. Before the catalytic reaction started, O2 was introduced into the reactor to remove CO2 and other gases. After the reaction was completed, the concentration of the liquid product produced in the experiment was detected by a colorimetric method using an ultraviolet spectrophotometer.

[0078] Example 6

[0079] The application of fluorinated covalent organic framework materials (F-COF-2) in the photocatalytic production of hydrogen peroxide specifically includes the following steps:

[0080] The oxygen reduction reaction occurs in a quartz tube, with F-COF-2 as the covalent organic framework material and water as the reaction solution. A light intensity of 1500 mW / cm² is used. -2 A xenon lamp was used as the irradiation light source. During the catalytic process, the temperature of the space where the quartz tube was located was maintained at 25°C. Before the catalytic reaction started, air was introduced into the reactor. After the reaction was completed, the concentration of the liquid product produced in the experiment was detected by a colorimetric method using an ultraviolet spectrophotometer.

[0081] Combining Examples 5 and 6, by Figure 11 It can be seen that, under pure oxygen conditions, the highest rate of photoreduction of O2 to H2O2 by the fluorinated covalent organic framework material (F-COF-2) is greater than 1.5 mmol g. -1 h -1 Under air conditions, the highest rate of photoreduction of air to produce H2O2 is greater than 0.7 mmol g. -1 h -1 The results showed that fluorinated covalent organic framework materials (F-COF-2) have the advantages of being highly efficient, green, and low-cost in photoreduction of O2 and H2O2 production from air as catalytic materials.

[0082] Example 7

[0083] like Figure 1c As shown, the fluorinated covalent organic framework material (F-COF-3) is mainly synthesized from fluorinated phenyl(p)diamine 3 and functionalized trimesin 3 via a Schiff base reaction of aldehyde-amine condensation. The two are linked by covalent bonds. Specifically, it is prepared by the following method:

[0084] Accurately weighed fluorophenyl(p)diamine 3 and functionalized trimesoaldehyde were placed in a heat-resistant glass tube. Chlorobenzene solvent and then alcohol solvent were added sequentially to the glass tube, and the mixture was sonicated until the solid powder was completely dissolved. The tube was then evacuated under liquid nitrogen conditions using a vacuum pump, and the tube was sealed after evacuation. The reaction mixture was then placed in an oven and heated at 100-180°C for 24-80 hours.

[0085] Finally, the reactants were cooled to room temperature, and the reactants were repeatedly washed and centrifuged with furan solvents until the supernatant was colorless. The supernatant was then dried under vacuum to obtain a solid powder fluorinated covalent organic framework material (F-COF-3).

[0086] Structural analysis was performed on the fluorinated covalent organic framework material (F-COF-3) prepared above, and the results were as follows: Figure 12-15 The results shown; by Figure 12 It can be seen that the fluorinated covalent organic framework material (F-COF-3) has sharp diffraction peaks, indicating that it is a highly crystalline framework material. From... Figure 13 It can be seen that the reactant fluorine ligands are at 3450 cm⁻¹ -1 There is a distinct double peak characteristic of -NH2 at 1644 cm⁻¹, and the functionalized phenyltrialdehyde reactant shows a peak characteristic of -NH2 at 1644 cm⁻¹. -1 A stretching vibration of -C=H exists at this point. Fluorinated covalent organic framework materials (F-COF-3) do not exhibit the aforementioned characteristic absorption peak, only showing one at 1620 cm⁻¹. -1 The position shows a characteristic absorption peak of -C=N-, thus proving the successful synthesis of the fluorinated covalent organic framework material (F-COF-3).

[0087] Morphological analysis was performed on the fluorinated covalent organic framework material (F-COF-3) prepared above, and the results were as follows: Figure 14-15 The results shown; by Figure 14 It is known that the fluorinated covalent organic framework material (F-COF-3) has a sheet-like structure, providing further evidence for its successful preparation. For example... Figure 15 As shown, in order to investigate the corresponding distribution of each element, energy-dispersive X-ray spectroscopy analysis was performed on the fluorinated covalent organic framework material (F-COF-3) to determine the elemental distribution. The results showed that C, N, O and F elements were uniformly distributed in the fluorinated covalent organic framework (F-COF-3) catalytic material.

[0088] Example 8

[0089] The application of fluorinated covalent organic framework materials (F-COF-3) in the photocatalytic production of hydrogen peroxide specifically includes the following steps:

[0090] The oxygen reduction reaction, catalyzed by F-COF-3, occurs in a quartz tube. The fluorinated covalent organic framework material (F-COF-3) serves as the catalyst, water is the reaction solution, and a light intensity of 1500 mW / cm² is used. -2 A xenon lamp was used as the irradiation light source. During the catalytic process, the temperature of the space where the quartz tube was located was maintained at 25°C. Before the catalytic reaction started, O2 was introduced into the reactor to remove CO2 and other gases. After the reaction was completed, the concentration of the liquid product produced in the experiment was detected by a colorimetric method using an ultraviolet spectrophotometer.

[0091] Example 9

[0092] The application of fluorinated covalent organic framework materials (F-COF-3) in the photocatalytic production of hydrogen peroxide specifically includes the following steps:

[0093] The oxygen reduction reaction, catalyzed by F-COF-3, occurs in a quartz tube. The covalent organic framework material F-COF-3 serves as the catalyst, water is the reaction solution, and a light intensity of 1500 mW / cm² is used. -2 A xenon lamp was used as the irradiation light source. During the catalytic process, the temperature of the space where the quartz tube was located was maintained at 25°C. Before the catalytic reaction started, air was introduced into the reactor. After the reaction was completed, the concentration of the liquid product produced in the experiment was detected by a colorimetric method using an ultraviolet spectrophotometer.

[0094] Combining Examples 8 and 9, by Figure 16 It can be seen that, under pure oxygen conditions, the highest rate of photoreduction of O2 to H2O2 by the fluorinated covalent organic framework material (F-COF-3) is greater than 0.4 mmol g. -1 h -1 Under air conditions, the highest rate of photoreduction of air to produce H2O2 is greater than 0.25 mmol g. -1 h -1 The results showed that fluorinated covalent organic framework materials (F-COF-3) have the advantages of being highly efficient, green, and low-cost photocatalytic reduction of O2 and H2O2 production from air.

[0095] The above description is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. The application of fluorinated covalent organic framework materials in the photocatalytic production of hydrogen peroxide, characterized in that, The structural formula of the fluorinated covalent organic framework material is: , or 。 2. The application as described in claim 1, characterized in that, Hydrogen peroxide is prepared by catalytic reaction under pure oxygen or air conditions, using the fluorinated covalent organic framework material as a catalyst and water as the reaction system solution, under natural light or xenon lamp irradiation.

3. The application as described in claim 1, characterized in that, The mass ratio of catalyst to water shall not be less than 1:

6.

4. The application as described in claim 1, characterized in that, When the structural formula of the fluorinated covalent organic framework material is as follows: ， Under xenon lamp irradiation in pure oxygen conditions, the concentration of hydrogen peroxide produced is greater than 400 μM, and the rate of H2O2 production is greater than 4 mmol g. -1 h -1 .

5. The application as described in claim 1, characterized in that, Under xenon lamp irradiation, when the structural formula of the fluorinated covalent organic framework material is as follows: ， In air, the concentration of hydrogen peroxide generated is greater than 300 μM, and the rate of H2O2 production is greater than 3 mmol g. -1 h -1 .

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