Preparation method and application of cerium single-atom-anchored polyhydroxylated porphyrin covalent organic framework photocatalyst
By anchoring cerium single atoms in polyhydroxyporphyrin COF, the problem of low oxygen adsorption and charge separation efficiency of porphyrin-based COF photocatalysts was solved, and efficient hydrogen peroxide production was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HEILONGJIANG UNIV
- Filing Date
- 2026-02-05
- Publication Date
- 2026-05-29
AI Technical Summary
Existing porphyrin-based COF photocatalysts have low photogenerated carrier separation efficiency and lack oxygen adsorption sites, resulting in unsatisfactory hydrogen peroxide production performance.
By anchoring cerium single atoms in polyhydroxyporphyrin COF, and introducing abundant polar oxygen-containing functional groups and cerium atoms, oxygen adsorption and photogenerated charge separation are promoted, forming a cerium single-atom-anchored polyhydroxyporphyrin COF photocatalyst.
It improves oxygen adsorption capacity and directional transfer of photogenerated electrons, enhancing hydrogen peroxide production activity. Each gram of catalyst can produce 11.04 millimoles of hydrogen peroxide.
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Figure CN122103498A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for preparing a photocatalyst and its application. Background Technology
[0002] With the increasing global demand for clean energy and green technologies, developing efficient and low-carbon chemical synthesis methods has become one of the core challenges in scientific research and industrial applications. Hydrogen peroxide, as an important green oxidant, plays an irreplaceable role in environmental remediation, chemical synthesis, medical and health applications, and energy conversion. However, the currently dominant industrial anthraquinone process is cumbersome, energy-intensive, and relies on precious metal catalysts and organic solvents, posing safety hazards and environmental pollution problems. Semiconductor photocatalysis technology can achieve oxygen reduction to produce hydrogen peroxide under mild conditions, representing a feasible strategy to address these issues.
[0003] The rational design and preparation of efficient and stable photocatalysts for oxygen reduction to produce hydrogen peroxide is of great significance. Among numerous photocatalysts, COFs (Chemical Oxygen-Free Formings) have attracted widespread attention due to their unique advantages, including the high predictability and precise tunability of their chemical structures. This allows researchers to rationally design the band structure, light absorption range, and active site distribution of materials at the molecular level. However, despite their ordered structures, most COFs still exhibit lower intrinsic carrier mobility than traditional inorganic semiconductors, indicating room for improvement in charge transport efficiency. They also have weak O2 adsorption capacity and lack surface catalytic centers for oxygen reduction, typically exhibiting cross-functionalized oxygen reduction photocatalysis for hydrogen peroxide production. Therefore, introducing polyhydroxy functional groups into the pores of COFs can promote O2 adsorption and induce asymmetric charge distribution to facilitate charge separation. Furthermore, introducing cerium single atoms to construct oxygen reduction active sites can further enhance their hydrogen peroxide production activity.
[0004] However, current designs for porphyrin-based COF photocatalysts typically lack the design of oxygen adsorption activation sites. Furthermore, the rational design for promoting extensive charge separation and transfer in porphyrin-based COFs often neglects the introduction of catalytically active sites, resulting in unsatisfactory performance in pipeline hydrogen peroxide production. Summary of the Invention
[0005] The present invention aims to address the problems of low photogenerated carrier separation efficiency and lack of catalytic active centers with oxygen adsorption sites in the preparation of porphyrin-based COF photocatalysts in existing technologies, thereby providing a method for preparing and applying a cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst.
[0006] One method for preparing a cerium single-atom-anchored polyhydroxyporphyrin COF photocatalyst is as follows:
[0007] I. Preparation of polyhydroxyporphyrin COF:
[0008] 1.1 First, the ligand 5,10,15,20-tetra(4-aminophenyl)porphyrin, the linker 2,5-dihydroxyterephthalaldehyde, and pyruvic acid are added to an organic solvent, and then ultrasonically stirred until completely dissolved. Then, the initiator is added, and ultrasonic stirring is continued to disperse it evenly.
[0009] 1.2 Add the prepared solution to the Pyrex tube of the reactor, degas it before sealing, and perform three cycles of freezing-evacuation-thawing. Then place it in an oven at 120°C for 72 hours.
[0010] 1.3 During the reaction, the monomer enhances the reversible covalent bond reaction, and the imine condensation gradually forms COF crystals. The mixed solution after the reaction is filtered and repeatedly washed with N,N-dimethylformamide, tetrahydrofuran and acetone to remove unreacted substances and solution. Then it is vacuum dried to obtain the polyhydroxyporphyrin COF catalyst.
[0011] II. Anchoring cerium single atoms in polyhydroxyporphyrin COF:
[0012] A certain amount of cerium nitrate was placed in a methanol solution and sonicated until completely dissolved. Then, a certain amount of polyhydroxyporphyrin COF catalyst was added to the methanol solution and sonicated until completely dispersed and uniform. The mixture was then stirred at room temperature for 12 hours. After the reaction was completed, the mixture was filtered and dried under vacuum to obtain cerium single-atom anchored polyhydroxyporphyrin COF.
[0013] The principle of this invention:
[0014] First, the ligand 5,10,15,20-tetratetra(4-aminophenyl)porphyrin and the linker 2,5-dihydroxyterephthalaldehyde undergo imine condensation in a solution of 1,2-dichlorobenzene and 1-butanol under the initiator acetic acid to form a COF topology. Simultaneously added pyruvic acid acts as a nucleophile, attacking the carbon atom in the imine bond, undergoing a nucleophilic addition-cyclization-aromatization reaction to generate a 4-carboxyquinoline bond, thus forming a polyhydroxyporphyrin COF. The polyhydroxyporphyrin COF is then adsorbed by stirring in cerium nitrate dissolved in methanol solution, finally yielding a cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst.
[0015] Advantages of this invention:
[0016] I. The cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in this invention has abundant polar oxygen-containing functional groups, which can adsorb oxygen.
[0017] II. Compared with existing porphyrin-based COF photocatalysts, the cerium single-atom anchored polyhydroxy porphyrin COF photocatalyst prepared in this invention has polyhydroxy oxygen-containing polar functional groups that can induce asymmetric charge distribution, which is beneficial to the directional transfer and separation of photogenerated electrons; cerium atoms can activate oxygen and improve the hydrogen peroxide production activity.
[0018] III. The cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared by this invention is suitable for use as a photocatalytic reduction of oxygen. Each gram of cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst can produce 11.04 millimoles of hydrogen peroxide by reducing oxygen.
[0019] A cerium single-atom-anchored polyhydroxyporphyrin COF photocatalyst is used as a photocatalyst to catalyze the reduction of oxygen to produce hydrogen peroxide. Attached Figure Description
[0020] Figure 1 This is an X-ray diffraction pattern of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1;
[0021] Figure 2 This is a transmission electron microscope image of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1;
[0022] Figure 3 The fluorescence spectrum of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1 is shown.
[0023] Figure 4 This is a photocatalytic hydrogen peroxide activity diagram of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1;
[0024] Figure 5 This is a photocatalytic water oxidation activity diagram of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1;
[0025] Figure 6 The solid-state fluorescence of the indium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 2;
[0026] Figure 7 This is the UV solid absorption spectrum of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 2;
[0027] Figure 8 The bar chart shows the hydrogen peroxide production of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1, the γ-indium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 2, and the lanthanum single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 3. Detailed Implementation
[0028] The following embodiments further illustrate the content of the present invention, but should not be construed as limiting the present invention. Any modifications and substitutions made to the methods, steps, or conditions of the present invention without departing from the essence of the invention are within the scope of the present invention.
[0029] Specific Implementation Method 1: This implementation method describes a method for preparing a cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst, which is specifically completed according to the following steps:
[0030] I. Polyhydroxyporphyrin COF:
[0031] 1.1 First, 5,10,15,20-tetra(4-aminophenyl)porphyrin and the linker 2,5-dihydroxyterephthalaldehyde are added to an organic solvent, then sonicated and stirred until completely dissolved, then the initiator is added and stirring is continued for a period of time.
[0032] 1.2. The previously prepared solution was added to the Pyrex tube of the reactor. Before sealing, it was degassed by three cycles of freezing-evacuation-thawing. Then it was placed in an oven at 120°C for 72 hours to obtain the reaction product.
[0033] 1.3. The reactants were filtered and repeatedly washed with N,N-dimethylformamide, tetrahydrofuran and acetone to remove unreacted substances and solution. The mixture was then dried under vacuum to obtain the polyhydroxyporphyrin COF catalyst.
[0034] II. Anchoring cerium single atoms in polyhydroxyporphyrin COF materials:
[0035] A certain amount of cerium nitrate was placed in a methanol solution and sonicated until completely dissolved. Then, a certain amount of polyhydroxyporphyrin COF catalyst was added to the methanol solution and sonicated until completely dispersed and uniform. The mixture was then stirred at room temperature for 12 hours. After the reaction was completed, the mixture was filtered and dried under vacuum to obtain a cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst.
[0036] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the organic solvent mentioned in step 1.1 is 1,2-dichlorobenzene and 1-butanol; the initiator mentioned in step 1.1 is an acetic acid solution. The other steps are the same as in Specific Implementation Method One.
[0037] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in the following ways: the mass ratio of the ligand and linker to the organic solvent in step 1.1 is (6.7 mg: 6.4 mg): (0.5 mL: 0.5 mL); the volume ratio of the acetic acid initiator to the organic solvent in step 1.1 is (0.1 mL): (0.5 mL: 0.5 mL); and the volume ratio of pyruvate to the organic solvent in step 1.1 is (2 μL): (0.5 mL: 0.5 mL). The other steps are the same as in Specific Implementation Method One or Two.
[0038] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that: before the degassing treatment described in step 1.2, nitrogen gas is introduced into the Pyrex tube to remove as much oxygen as possible. The aeration time is 15-20 minutes. The other steps are the same as in Specific Implementation Methods One to Three.
[0039] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that the reaction time in step 1.1 is 48 hours; the reaction temperature in step 1.2 is 150°C. The other steps are the same as in Specific Implementation Methods One to Four.
[0040] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that the washing described in step 1.3 is replaced with centrifugation at a speed of 3000 r / min-4000 r / min, and the number of centrifugations is more than 5 times until the upper layer is a clear liquid. The other steps are the same as in Specific Implementation Methods One to Five.
[0041] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One through Six in that the washing described in step 1.3 is replaced with centrifugation at a speed of 3000-4000 r / min, once. The centrifuged sample is then extracted and refluxed using an N,N-dimethylformamide and methanol solution. The other steps are the same as in Specific Implementation Methods One through Six.
[0042] Specific Implementation Method Eight: The difference between this implementation method and Specific Implementation Methods One to Seven is that the ratio of polyhydroxyporphyrin COF, cerium nitrate, and methanol in step two is (60mg):(60mg):(50ml). The other steps are the same as in Specific Implementation Methods One to Seven.
[0043] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One through Eight in that: in step two, methanol is used to centrifuge and clean the cerium single-atom anchored polyhydroxyporphyrin COF catalyst, centrifuging 3-5 times, followed by drying at 60℃-80℃ for 10-12 hours. Other steps are the same as in Specific Implementation Methods One through Eight.
[0044] Specific Implementation Method 10: This implementation method is the application of a cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst in photocatalytic hydrogen peroxide production or photocatalytic water oxidation.
[0045] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0046] Example 1: The preparation method of cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst is carried out according to the following steps:
[0047] I. Preparation of polyhydroxyporphyrin COF:
[0048] 1.1 First, 5,10,15,20-tetra(4-aminophenyl)porphyrin and the linker 2,5-dihydroxyterephthalaldehyde were added to a solvent of 1,2-dichlorobenzene and 1-butanol. The mixture was then sonicated and stirred until completely dissolved. Acetic acid initiator was then added, and sonication was continued for 20 minutes to obtain the initial reaction solution.
[0049] The volume ratio of 1,2-dichlorobenzene, 1-butanol, and acetic acid mentioned in step 1.1 is 1 mL: 1 mL: 0.2 mL;
[0050] 1.2. The previously prepared solution was added to the Pyrex tube of the reactor. Before sealing, it was degassed and subjected to three cycles of freezing-evacuation-thawing. Then it was placed in an oven at 120°C for 72 hours to obtain the reaction product.
[0051] The degassing process described in step 1.2 involves injecting nitrogen into the tube before degassing, with a ventilation time of 10-15 minutes.
[0052] 1.3. The reactants were filtered and repeatedly washed with N,N-dimethylformamide, tetrahydrofuran and acetone to remove unreacted substances and solution. The mixture was then dried under vacuum to obtain the polyhydroxyporphyrin COF catalyst.
[0053] The cleaning process described in step 1.3 involves first washing with N,N-dimethylformamide and tetrahydrofuran until the solution becomes clear and transparent, and then washing with acetone 2-3 times.
[0054] II. Anchoring cerium single atoms in polyhydroxyporphyrin COF:
[0055] A certain amount of cerium nitrate was placed in a methanol solution and sonicated until completely dissolved. Then, a certain amount of polyhydroxyporphyrin COF was added to the methanol solution and sonicated until completely dispersed and uniform. The mixture was then stirred at room temperature for 12 hours. After the reaction was completed, the mixture was filtered and dried under vacuum to obtain cerium single-atom anchored polyhydroxyporphyrin COF.
[0056] In step two, the mass ratio of polyhydroxyporphyrin COF to cerium nitrate is 30 mg: 30 mg, and the volume of methanol is 30 mL.
[0057] The vacuum drying temperature in step two is 80℃, and the time is 12 hours.
[0058] Figure 1 This is an X-ray diffraction pattern of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1;
[0059] Depend on Figure 1 It can be seen that the introduction of polar oxygen-containing functional groups hydroxyl and carboxyl groups, as well as cerium single atoms, did not change the crystal phase and degree of crystallinity of the covalent organic framework.
[0060] Figure 2 This is a transmission electron microscope image of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1;
[0061] Depend on Figure 2 It can be seen that the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in this experiment has a two-dimensional ultrathin nanosheet structure, which is beneficial to gas adsorption and increases the mass transfer rate.
[0062] Figure 3 This is the solid-state fluorescence spectrum of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1;
[0063] Depend on Figure 3 It can be seen that the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1 is beneficial to the transfer and separation of photogenerated charges.
[0064] 0.01 g of the cerium single-atom-anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1 was added to 10 mL of distilled water, then transferred to a 30 mL quartz glass reactor, and oxygen was introduced. A light intensity of 100 mW / cm² was used. 2 The quartz glass reactor was irradiated with ultraviolet-visible light for 1 hour. The liquid in the reactor was then extracted and filtered. 3 mL of the filtered reaction solution was taken and reacted with 1 mL of 0.4 mol / L potassium iodide and 0.1 mol / L potassium hydrogen phthalate to produce a colorimetric reaction for 50 min. Finally, the results were detected using ultraviolet-visible diffuse reflectance spectroscopy. (See attached table). Figure 4 As shown;
[0065] Figure 4 This is a photocatalytic methane oxidation activity diagram of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1;
[0066] Depend on Figure 4It can be seen that the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1 is beneficial for the photocatalytic production of hydrogen peroxide.
[0067] The photocatalytic water oxidation using the cerium single-atom-anchored polyhydroxyporphyrin COF photocatalyst prepared in Experiment 1 was carried out according to the following steps:
[0068] 0.05 g of the cerium single-atom-anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1 was added to 50 mL of ultrapure water, then transferred to a 100 mL quartz glass reactor, and a light intensity of 100 mW / cm² was used. 2 The quartz glass reactor was irradiated with ultraviolet-visible light for 1 hour, and then the gases in the quartz glass reactor were extracted separately. Finally, the gases were detected by chromatography. The detection results are shown in the figure. Figure 5 As shown;
[0069] Figure 5 This is a photocatalytic water oxidation activity diagram of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1;
[0070] Depend on Figure 5 It can be seen that the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1 is beneficial for photocatalytic water oxidation.
[0071] Example 2: The difference between this example and Example 1 is that the metal mentioned in step two is a transition metal methanol solution, which yields a transition metal single-atom anchored polyhydroxyporphyrin COF photocatalyst, taking an indium single-atom anchored polyhydroxyporphyrin COF photocatalyst as an example. Other steps and parameters are the same as in Example 1.
[0072] The indium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared using the solid-state fluorescence detection example has the following detection results: Figure 6 As shown;
[0073] Figure 6 This is the surface photovoltage spectrum of the indium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 2;
[0074] Depend on Figure 6 It can be seen that the indium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in this experiment has high charge separation performance, proving that this hollow one-dimensional nanotube composite is beneficial for photocatalytic methane oxidation.
[0075] The indium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in this experiment was detected by ultraviolet-visible absorption spectroscopy. The detection results are as follows: Figure 7 As shown;
[0076] Figure 7This is the UV solid absorption spectrum of the indium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 2;
[0077] Depend on Figure 7 It can be seen that the indium single-atom anchored polyhydroxy porphyrin COF photocatalyst prepared in Example 2 has a strong ultraviolet light response and an extended visible light response, proving that this indium single-atom anchored polyhydroxy structure is beneficial to enhancing light absorption.
[0078] Example 3: The difference between this example and Example 1 is that the metal source in step four is a rare earth metal methanol solution, which yields a rare earth metal single-atom anchored polyhydroxyporphyrin COF photocatalyst, taking a lanthanum single-atom anchored polyhydroxyporphyrin COF photocatalyst as an example. All other steps and parameters are the same as in Example 1.
[0079] 0.01g of the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1, 0.01g of the indium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 2, and 0.01g of the lanthanum single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 3 were respectively added to 10mL of distilled water, then transferred to a 30mL quartz glass reactor, and oxygen was introduced. A light intensity of 100mW / cm² was used. 2 The quartz glass reactor was irradiated with ultraviolet-visible light for 1 hour. The liquid in the reactor was then extracted and filtered. 3 mL of the filtered reaction solution was taken and reacted with 1 mL of 0.4 mol / L potassium iodide and 0.1 mol / L potassium hydrogen phthalate to produce a colorimetric reaction for 50 min. Finally, the results were detected using ultraviolet-visible diffuse reflectance spectroscopy. (See attached table). Figure 4 As shown;
[0080] Figure 8 This is a bar chart of hydrogen peroxide prepared by the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst in Example 1, the indium single-atom anchored polyhydroxyporphyrin COF photocatalyst in Example 2, and the lanthanum single-atom anchored polyhydroxyporphyrin COF photocatalyst in Example 3.
[0081] from Figure 8 It can be seen that the cerium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 1 has higher photocatalytic hydrogen peroxide production performance than the indium single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 2 and the lanthanum single-atom anchored polyhydroxyporphyrin COF photocatalyst prepared in Example 3.
[0082] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.
Claims
1. A method for preparing a cerium single-atom-anchored polyhydroxyporphyrin covalent organic framework photocatalyst, characterized in that, Includes the following steps: I. Preparation of polyhydroxyporphyrin COF: 1.1 Add the ligand 5,10,15,20-tetra(4-aminophenyl)porphyrin, the linker 2,5-dihydroxyterephthalaldehyde and pyruvic acid to an organic solvent containing 1,2-dichlorobenzene and 1-butanol in a volume ratio of 1:1, and sonicate until completely dissolved. Then add acetic acid and continue to sonicate until evenly dispersed. 1.2 Add the solution obtained in step 1.1 into the Pyrex tube reactor, and degas it before sealing. The degassing process consists of three cycles of freezing-evacuation-thawing. Then place the Pyrex tube in an oven and react at 120°C for 48-72 hours. 1.3 After the reaction is complete, the mixed solution is filtered and washed repeatedly with N,N-dimethylformamide, tetrahydrofuran and acetone in sequence. After vacuum drying, the polyhydroxyporphyrin COF catalyst is obtained. II. Anchoring of cerium single atoms: Cerium nitrate was added to a methanol solution and sonicated until completely dissolved. Then, the polyhydroxyporphyrin COF catalyst from step I was added. After being sonicated and dispersed evenly, the mixture was stirred at room temperature for 12 hours, filtered, and vacuum dried to obtain a cerium single atom-anchored polyhydroxyporphyrin COF photocatalyst.
2. The method for preparing the cerium single-atom anchored polyhydroxyporphyrin covalent organic framework photocatalyst according to claim 1, characterized in that, In step 1.1, the organic solvent is 1,2-dichlorobenzene and 1-butanol; the initiator in step 1.1 is an acetic acid solution.
3. The method for preparing the cerium single-atom anchored polyhydroxyporphyrin covalent organic framework photocatalyst according to claim 2, characterized in that, In step 1.1, the mass ratio of the ligand and linker to the volume ratio of the organic solvent 1,2-dichlorobenzene and 1-butanol is 6.7 mg: 6.4 mg: 0.5 mL: 0.5 mL; the volume ratio of the initiator to the organic solvent 1,2-dichlorobenzene and 1-butanol is 0.1 mL: 0.5 mL: 0.5 mL.
4. The method for preparing the cerium single-atom-anchored polyhydroxyporphyrin covalent organic framework photocatalyst according to claim 3, characterized in that, In step 1.2, nitrogen gas is introduced into the Pyrex tube for 15-20 minutes before degassing.
5. The method for preparing the cerium single-atom anchored polyhydroxyporphyrin covalent organic framework photocatalyst according to claim 4, characterized in that, The reaction time for step 1.1 is 48 hours; the reaction temperature for step 1.2 is 150°C.
6. The method for preparing the cerium single-atom anchored polyhydroxyporphyrin covalent organic framework photocatalyst according to claim 1, characterized in that, In step 1.3, the washing method is replaced by centrifugation, with a centrifugation speed of 3000 r / min-4000 r / min and a centrifugation number of 5 times or more, until the upper layer is clear liquid.
7. The method for preparing the cerium single-atom anchored polyhydroxyporphyrin covalent organic framework photocatalyst according to claim 6, characterized in that, In step 1.3, the washing method is replaced by centrifugation, with a centrifugation speed of 3000 r / min-4000 r / min and a centrifugation count of 1; the centrifuged sample is then subjected to extraction reflux, and the extraction solution is a mixture of N,N-dimethylformamide and methanol.
8. The method for preparing the cerium single-atom anchored polyhydroxyporphyrin covalent organic framework photocatalyst according to claim 1, characterized in that, In step two, the ratio of polyhydroxyporphyrin COF catalyst, cerium nitrate, and methanol is 60 mg: 60 mg: 50 mL.
9. The method for preparing the cerium single-atom anchored polyhydroxyporphyrin covalent organic framework photocatalyst according to claim 1, characterized in that, In step two, the cerium single-atom anchored polyhydroxyporphyrin COF catalyst is centrifuged and cleaned with methanol 3-5 times, and then dried at 60℃-80℃ for 10-12 hours.
10. The application of a cerium single-atom-anchored polyhydroxyporphyrin covalent organic framework photocatalyst prepared by the method described in any one of claims 1 to 9 in photocatalytic hydrogen peroxide production or photocatalytic water oxidation.