Preparation and application of J-type porphyrin supramolecule (TCPP-LSA-J) with ultra-long near-infrared absorption

Abstract

The invention belongs to the field of green chemical industry, and discloses a preparation method of a J-type porphyrin supramolecule (TCPP-LSA-J) with ultra-long near-infrared absorption performance and application of the J-type porphyrin supramolecule in preparation of hydrogen peroxide through photo-thermal catalysis under the condition of no sacrificial agent. The method comprises the following steps: mixing the prepared TCPP-LSA-J with ultrapure water (50.0-100.0 mL), irradiating by a xenon lamp (lambda is greater than or equal to 420 nm) under the conditions of 20-100 DEG C, O2 flow of 25.0-50.0 mL / min and continuous stirring, reacting, filtering and concentrating to obtain a high-concentration hydrogen peroxide aqueous solution. Under the LDH confinement effect, the TCPP molecular layers are arranged in an inclined and staggered mode to form J-type supramolecules, the absorption wavelength is expanded to the second near-infrared region (1750 nm), and efficient utilization of solar energy is achieved. The system does not need an organic sacrificial agent, is green and environment-friendly, takes O2 as an oxygen source, and is safe, low in energy consumption, mild in reaction condition, simple and convenient to operate and high in yield.

Description

Technical Field

[0001] The invention relates to the preparation of a porphyrin supramolecule with ultralong near-infrared absorption and application of the same in producing hydrogen peroxide by photothermal catalysis without sacrificial reagents, and belongs to the field of green chemical industry. Background Art

[0002] With the increasing global demand for clean energy and sustainable chemical synthesis, photocatalysis has attracted widespread attention as a green and efficient energy conversion method. Among them, the photocatalytic generation of hydrogen peroxide (H2O2) has become a research hotspot due to its wide application in environmental remediation, chemical synthesis, and energy storage. However, traditional photocatalytic materials often face problems such as low efficiency, poor stability, and dependence on precious metals, which limit their large-scale application. In this context, supramolecular photocatalytic systems based on 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) have become potential candidates for addressing these challenges due to their unique structural and performance advantages.

[0003] TCPP, a typical porphyrin compound, possesses excellent light absorption properties and a tunable electronic structure, enabling efficient visible light-driven photocatalytic reactions. In 2015, Zhang's team first reported the application of TCPP-based supramolecular assemblies in photocatalysis, demonstrating their unique advantages in photogenerated charge carrier separation and transport. This breakthrough provides new insights into the design of highly efficient photocatalytic materials. However, conventional TCPP systems still face challenges in photocatalytic H2O2 production due to low yields and insufficient photostability.

[0004] In recent years, supramolecular assemblies have attracted much attention due to their excellent photocatalytic performance. This assembly method not only enhances the light absorption capacity, but also promotes the effective separation of photogenerated electrons and holes, thereby improving the photocatalytic efficiency. In addition, the dynamic reversibility of the supramolecular structure enables the material to have self-repairing ability during the reaction process, further improving its stability. In particular, the performance of J-type supramolecular assemblies in photocatalysis is significantly better than that of traditional H-type supramolecular assemblies, providing a new direction for its application in the photocatalytic generation of H2O2. In H-type supramolecular molecules, TCPP molecules are stacked in a face-to-face manner, while in J-type supramolecular molecules, TCPP molecules are arranged in a head-to-tail manner, forming a stepped structure. The structure of J-type supramolecular molecules is more conducive to the capture and transmission of light energy, making its light absorption ability in the near-infrared region significantly better than that of H-type supramolecular molecules.

[0005] Previous research has shown that TCPP molecules are arranged in an orderly fashion through the confinement effect of hydrotalcite (LDH), forming a supramolecular material with a well-defined structure. Furthermore, the LDH template effect allows TCPP to form a J-shaped supramolecular structure. This TCPP-based supramolecular photocatalytic system provides an efficient and green solution for the photocatalytic generation of H2O2. With further research, the TCPP supramolecular photocatalytic system will become an important development direction in the field of photocatalysis, driving innovation and advancement in green H2O2 synthesis technology. Summary of the Invention

[0006] The present invention first provides a 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin J-type supramolecular material (TCPP-LSA-J) with ultra-long near-infrared absorption and a preparation method thereof. The TCPP-LSA-J material can photocatalytically generate water and oxygen at a rate of 3.01 mmol·g under xenon lamp irradiation. -1 ·h -1 .

[0007] The second object of the present invention is to provide a TCPP-LSA-J material prepared by the method described above to fully utilize the near-infrared light band.

[0008] By utilizing the confinement effect of LDH and the narrow bandgap effect of the J-type assembly, the preparation method of TCPP-LSA-J material that fully utilizes visible light and near-infrared light under xenon lamp irradiation is realized as follows:

[0009] a. Preparation of Mg3Al-NO3-LDH: First, add 200 mL of 1.00 mM NaNO3 solution to a 1000 mL four-necked flask. 200.00 mL of a salt solution containing Mg(NO3)2 and Al(NO3)3·9H2O is labeled Solution A, and 200.00 mL of a NaOH solution is labeled Solution B. Both are added dropwise to the flask under vigorous stirring, maintaining the pH of the suspension at approximately 8. After stirring, the mixture is aged at room temperature under a N2 atmosphere for 24 hours and then washed with decarbonized water to obtain Mg3Al-NO3-LDH colloid.

[0010] b. Preparation of TCPP-Mg3Al-NO3-LDH: Mg3Al-NO3-LDH was added to a TCPP solution at 80°C under a nitrogen atmosphere and ion exchange was performed for 48 hours to obtain TCPP-LDH. The product was then diluted with deionized water and ethanol, and then dispersed in ethanol for further use.

[0011] c. Preparation of TCPP-LSA-J: TCPP-LDH was treated in a propionic acid / CH3OH solvent (v:v = 2:3, 3:3, 4:3, 5:3, 6:3, 4:3, 4:5, 4:6) to release long, ordered π-π stacked TCPP chains, defined as living seeds. The living seeds were sonicated for 0.5-2 h and allowed to grow for 6-24 h to reach the energy state required for stable LSA. During sonication, a mixture of ice and water was used to maintain a constant temperature of 0°C.

[0012] The present invention also provides the use of the TCPP-LSA-J catalyst prepared by the method described above in photocatalytic production of H2O2, wherein the method is:

[0013] a. As attached Figure 10 and attached Figure 11 Taking advantage of the excellent photocatalytic performance of TCPP-LSA-J catalyst, the effects of different catalyst masses, different oxygen flow rates, different solvent dosages, and different reaction temperatures on the photocatalytic performance were explored, and the optimal photocatalytic H2O2 production performance was finally determined to be 80°C.

[0014] b. As attached Figure 4 and attached Figure 5 Based on the ultra-long near-infrared absorption of TCPP-LSA-J catalyst, which can convert near-infrared light into heat, we designed a self-heating photothermal catalytic system that can achieve high photocatalytic performance without adding an external heat source.

[0015] Beneficial effects: The present invention provides a TCPP-LSA-J catalyst with ultra-long near-infrared absorption for the photothermal catalytic production of hydrogen peroxide without sacrificial reagents, which is green, environmentally friendly and pollution-free. Using O2 as an oxygen source and sunlight (visible light and near-infrared light) as an energy source at normal pressure, the present method has lower energy consumption and higher safety compared to the indirect synthesis of hydrogen peroxide by the industrial anthraquinone method. The present method for preparing hydrogen peroxide has mild reaction conditions and simple operation. The TCPP-LSA-J photocatalyst is mixed with ultrapure water, and the reaction mixture is irradiated with visible light and near-infrared light for a period of time without adding an external heat source. The reaction solution is then filtered to obtain a high-concentration hydrogen peroxide solution, which is then concentrated by vacuum distillation to obtain a commercially available concentration (approximately 3.00 wt%) of hydrogen peroxide. The method of the present invention has the advantages of high yield, efficient and stable catalytic performance, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 These are the XRD patterns of TCPP-LSA-J, TCPP-SA-H, TCPP-LDH and NO3-LDH under the conditions of Example 1 of the present invention.

[0017] Figure 2 This is the fluorescence image of TCPP-LSA-J, TCPP-SA-H and TCPP monomer under the conditions of Example 1 of the present invention.

[0018] Figure 3 UV-vis-NIRDRS diagram of TCPP-LSA-J, TCPP-SA-H and TCPP monomer under the conditions of Example 1 of the present invention.

[0019] Figure 4 Infrared thermal images of (A) TCPP-LSA-J surface, (B) TCPP-LSA-J suspension, and (C) water after irradiation with a 300W xenon lamp (λ≥420nm filter) for 40 min, and (D) TCPP-LSA-J suspension after irradiation with an infrared cutoff filter (<750nm) at the same temperature under the conditions of Example 1 of the present invention.

[0020] Figure 5 This is a comparison of the photocatalytic H2O2 production performance of TCPP-LSA-J under adiabatic conditions and TCPP-SA-H at 353K under the conditions of Example 3 of the present invention.

[0021] Figure 6 This is an SEM image of the TCPP-LSA-J distribution under the conditions of Example 4 of the present invention (inset: length distribution diagram obtained by evaluating 100 LSAs).

[0022] Figure 7 The aspect ratios of TCPP-LSA-J at different growth times and the corresponding SEM images under the conditions of Example 4 of the present invention are shown.

[0023] Figure 8 The UV-vis-NIR DRS graphs corresponding to different aspect ratios of TCPP-LSA-J under the conditions of Example 4 of the present invention and the supramolecular properties of TCPP-LSA-J produced by photocatalysis are shown.

[0024] Figure 9 The UV-vis-NIR DRS graph and photocatalytic H2O2 production performance of TCPP-LSA-J corresponding to different ultrasound times under the conditions of Example 5 of the present invention.

[0025] Figure 10 This is the effect of different catalyst masses, oxygen flow rates and water amounts on the photocatalytic performance of TCPP-LSA-J under the conditions of Example 6 of the present invention.

[0026] Figure 11 This is the effect of temperature on the photocatalytic production of H2O2 performance of TCPP-LSA-J under the conditions of Example 7 of the present invention.

[0027] Figure 12 The stability of H2O2 produced by TCPP-LSA-J under the conditions of Example 8 of the present invention. DETAILED DESCRIPTION

[0028] The present invention will be described in further detail below with reference to the embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0029] Hydrogen peroxide concentration test method:

[0030] Hydrogen peroxide and potassium titanium oxalate form a yellow complex solution. Its absorbance at 400 nm is measured using a UV spectrophotometer, and the hydrogen peroxide concentration is calculated using the Lambert-Beer law. Specifically, 3.9 mL of the sample to be tested (the reaction solution in the Examples or Comparative Examples) is taken every hour and filtered through a 0.22 μm filter to remove catalyst particles. Then, 1 mL of a 0.02 M potassium titanium oxalate solution and 0.1 mL of concentrated sulfuric acid are added. Finally, the absorbance of the solution is measured using a UV spectrophotometer, and the hydrogen peroxide concentration is calculated.

[0031] Example 1

[0032] Preparation of a TCPP-LSA-J photocatalyst with ultra-long near-infrared absorption in the present invention:

[0033] (1) Porphyrin is ultrasonically dispersed in water, and sodium hydroxide solution is added dropwise to adjust the pH value to 8. The porphyrin catalyst is 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP).

[0034] (2) Preparation of Mg3Al-NO3-LDH: First, add 200.0 mL of NaNO3 solution (1.00 mM) to a 1000 mL four-necked flask. 200.0 mL of a salt solution containing 3.85 g of Mg(NO3)2 and 1.876 g of Al(NO3)3·9H2O is labeled solution A, and 200.0 mL of a 5.00 g NaOH solution is labeled solution B. Both are added dropwise to the flask under vigorous stirring. The pH of the suspension is maintained at approximately 8 throughout the process. After stirring, the mixture is aged at room temperature under a N2 atmosphere for 24 h and washed with decarbonized water to obtain Mg3Al-NO3-LDH colloid. It can be used after quantification.

[0035] (3) TCPP-LDH was prepared by intercalating porphyrin into Mg3Al-NO3-LDH using an ion exchange method. Mg3Al-NO3-LDH was added to a TCPP solution at 80°C under a nitrogen atmosphere and ion exchange was performed for 48 hours to obtain TCPP-LDH. The product was then diluted with deionized water and ethanol, and then dispersed in ethanol as a storage solution for further use.

[0036] (4) TCPP-LDH was treated in a propionic acid / CH3OH solvent (v:v = 4:5) to release long, ordered π-π TCPP chains, defined as living seeds. The living seeds were sonicated for 1 h and allowed to grow for 12 h to reach the energy state required for stable LSA. During sonication, a mixture of ice and water was used to maintain a constant temperature of 0°C.

[0037] (5) Preparation of comparative sample TCPP-SA-H: 500 mg of TCPP was fully dissolved in 10.0 mL of 0.5 M KOH aqueous solution at 353 K. 0.10 M HCl aqueous solution was added dropwise using a constant pressure funnel until the pH reached 4. Self-assembled TCPP-SA-H was then synthesized by stirring in a water bath at 353 K for 72 h. After cooling, the mixture was centrifuged and washed multiple times until the pH reached 7. TCPP-SA-H was then collected by filtration and dried in vacuo at 353 K.

[0038] The XRD pattern, fluorescence pattern, UV-vis-NIR DRS pattern and infrared thermal imaging pattern of the target product were obtained as follows: Figure 1 、 2 , 3 and 4.

[0039] Depend on Figure 1 It can be seen that compared with the NO3-LDH precursor, the diffraction peak of TCPP-LDH shifted significantly from 2θ=11.76° to 7.80°, proving that TCPP was successfully embedded in LDH. After removing the LDH layer with a mixed solution of propionic acid / methanol (4:5 v / v), the obtained TCPP array was defined as a living supramolecular seed (LSA) due to its metastability and activity. seed ), due to the confinement effect of LDH, it is arranged in an orderly manner, and the released supramolecular active seeds further grow into active supramolecular (LSA). From the broad diffraction peaks appearing in XRD, it can be seen that LSA is a typical amorphous supramolecular rather than a crystalline structure. The XRD pattern calculation shows that the π-π spacing of TCPP-LSA-J is The spacing of TCPP-SA-H is approximately This indicates that the π-π spacing of TCPP-SA-H is smaller and the interaction force is stronger.

[0040] Depend on Figure 2 It can be seen that the fluorescence emission spectrum of TCPP-SA-H is blue-shifted compared to TCPP crystals. This is because its head-to-head arrangement generates exciton coupling, which leads to an increase in the excited state energy and a larger energy gap between the ground and excited states. On the other hand, TCPP-LSA-J is red-shifted due to a lower energy due to the head-to-tail arrangement.

[0041] Depend on Figure 3It can be seen that compared with TCPP monomer, the near-infrared absorption of TCPP-LSA-J extends to 1750nm, and it can utilize the near-infrared II region of sunlight for photocatalytic production.

[0042] Depend on Figure 4 Under irradiation with a 300W xenon lamp (λ ≥ 420nm filter), the temperature of the TCPP-LSA-J solution rapidly increased to approximately 338K within 30 minutes, while the temperature of pure water only increased to 314K. Infrared thermal imaging revealed that the local temperature on the TCPP-LSA-J surface increased even more dramatically, reaching 354K. The overall temperature of the suspension was higher than that of pure water, but lower than the local temperature, suggesting that TCPP-LSA-J can partially convert solar energy into heat by absorbing near-infrared light, thereby accelerating the increase in solution temperature. To verify this hypothesis, the suspension was illuminated using an infrared cutoff filter (<750nm). The results showed that the temperature of the suspension only increased to 313K, further confirming that TCPP-LSA-J's absorption of near-infrared light is the key factor causing the rapid temperature change.

[0043] Example 2

[0044] A method for producing H2O2 by photothermal catalysis using a TCPP-LSA-J catalyst with ultralong near-infrared absorption without sacrificial agent comprises the following steps:

[0045] In a 100.0 mL quartz reactor, 25.00 mg of TCPP-LSA-J catalyst was ultrasonically dissolved in 75.0 mL of ultrapure water and sealed with a stopper. Magnetic stirring was applied under adiabatic conditions, the O2 flow rate was maintained at 37.5 mL / min, and a light intensity of 200 mW / cm was used. 2 The samples were irradiated with a xenon lamp (λ≥420nm) for 4h.

[0046] Every hour, 3.9 mL of the reaction solution was sampled and filtered through a 0.22 μm filter to remove the catalyst. Then, 1 mL of potassium titanium oxalate solution (0.04 M) and 0.5 mL of concentrated sulfuric acid were added. The absorbance at 400 nm was measured using a UV spectrophotometer, and the H₂O₂ concentration was calculated using the Lambert-Beer law.

[0047] Example 3

[0048] A method for photothermal catalytic production of H₂O₂ using a TCPP-LSA-J catalyst with ultralong near-infrared absorption without sacrificial agents is disclosed. The method is described in Example 2, with the following differences: the type of porphyrin catalyst is changed from TCPP-LSA-J to TCPP-SA-H; and the amount of ultrapure water used is changed from 75.0 mL to 50.0 mL. The method specifically comprises the following steps:

[0049] In a 100.0 mL quartz reactor, 25.00 mg of TCPP-SA-H catalyst was ultrasonically dissolved in 50.0 mL of ultrapure water and sealed with a stopper. The reactor was heated (80°C) and magnetically stirred in an oil bath. The O2 flow rate was maintained at 37.5 mL / min, and an optical intensity of 200 mW / cm was used. 2 The samples were irradiated with a xenon lamp (λ≥420nm) for 4h.

[0050] Every hour, 3.9 mL of the reaction solution was sampled and filtered through a 0.22 μm filter to remove the catalyst. Then, 1.0 mL of a 0.04 M potassium titanium oxalate solution and 0.5 mL of concentrated sulfuric acid were added. The absorbance at 400 nm was measured using a UV spectrophotometer, and the H₂O₂ concentration was calculated using the Lambert-Beer law.

[0051] The performance comparison of the photothermal catalytic production of H2O2 by the obtained TCPP-LSA-J and TCPP-SA-H catalysts (Examples 2 and 3) is shown in FIG. Figure 5 shown.

[0052] Depend on Figure 5 It can be seen that under adiabatic conditions, the photocatalytic H2O2 production rate of TCPP-LSA-J reached 2.93mmol·g -1 ·h -1 , which is 2.4 times the yield of TCPP-SA-H at a constant temperature of 353K.

[0053] Example 4

[0054] A method for photothermal catalytic production of H2O2 using a TCPP-LSA-J catalyst with ultralong near-infrared absorption without sacrificial agent is disclosed, with reference to Examples 1 and 2, except that the growth time is adjusted from 12 h to 6, 18, and 24 h.

[0055] The SEM images of the TCPP-LSA-J distribution of the obtained target product (inset: length distribution diagram obtained by evaluating 100 LSAs), aspect ratios at different growth times, UV-vis-NIR DRS diagrams, and photocatalytic performance were obtained, as shown in Figure 2 . Figure 6 、 7 and 8.

[0056] Depend on Figure 6 Narrow dispersion is a key characteristic of active supramolecular assemblies. SEM images of TCPP-LSA-J (1 h of sonication and 12 h of growth) were used to examine the lengths of over 50 target supramolecular structures from three replicates to assess their polydispersity index. The average number length was 4.5 μm, indicating that TCPP-LSA-J is an active supramolecular assembly with excellent narrow dispersion.

[0057] Depend on Figure 7It can be seen that after 1 hour of ultrasonic treatment, the near-infrared absorption of TCPP-LSA-J grown for different times showed regular changes. The results showed that with the extension of growth time, the near-infrared absorption wavelength first increased and then decreased. The near-infrared absorption wavelength of the TCPP-LSA-J grown for 12 hours extended to 1750nm.

[0058] Depend on Figure 8 It can be seen that TCPP-LSA-J grown for 12 hours has the best photocatalytic performance.

[0059] Example 5

[0060] A method for producing H2O2 by photothermal catalysis without sacrificial agent using TCPP-LSA-J with ultralong near-infrared absorption is disclosed, with reference to Examples 1 and 2, except that the ultrasonic time is adjusted from 1 h to 0.5 and 1.5 h.

[0061] The UV-vis-NIR DRS graphs and photocatalytic properties of the target product TCPP-LSA-J at different ultrasonic times were obtained, such as Figure 9 shown.

[0062] Depend on Figure 9 It can be seen that TCPP-LSA-J with ultrasound for 1 h has the best photocatalytic performance.

[0063] Example 6

[0064] A method for photothermal catalytic production of H2O2 using TCPP-LSA-J with ultralong near-infrared absorption without sacrificial agent, with reference to Examples 1 and 2, except that: the mass of TCPP-LSA-J is adjusted from 25.00 mg to 12.50 and 37.50 mg; the oxygen flow rate is adjusted from 37.5 mL / min to 25.0 and 50.0 mL / min; and the amount of ultrapure water is adjusted from 75 mL to 50.0 and 100.0 mL.

[0065] The target product TCPP-LSA-J was obtained. The effects of adjusting the catalyst mass, oxygen flow rate and ultrapure water dosage on the photocatalytic performance were as follows: Figure 10 shown.

[0066] Depend on Figure 10 It can be seen that the optimal conditions for the photocatalytic production of hydrogen peroxide by TCPP-LSA-J are 25.00 mg, 37.5 mL / min and 75.0 mL, respectively.

[0067] Example 7

[0068] A method for producing H2O2 by photothermal catalysis without sacrificial agent using TCPP-LSA-J with ultralong near-infrared absorption is disclosed, with reference to Examples 1 and 2, except that the adiabatic conditions are adjusted to 20, 40, 60, 80, and 100°C.

[0069] The photocatalytic performance of the obtained target product TCPP-LSA-J at different temperatures was obtained, such as Figure 11 shown.

[0070] Depend on Figure 11 It can be seen that the optimal temperature for TCPP-LSA-J photocatalytic production of H2O2 is 80℃.

[0071] Example 8

[0072] A method for photocatalytically producing H2O2 without sacrificial agent using TCPP-LSA-J with ultralong near-infrared absorption is disclosed, with reference to Examples 1 and 2, except that the catalyst after 4 hours of reaction is washed and centrifuged before undergoing another 4 hours of photocatalytic experiment, and the experiment is repeated five times for a total of 20 hours.

[0073] Depend on Figure 12 It can be seen that there is no obvious downward trend in the H2O2 production after five cycle experiments, which proves that the catalyst has good stability.

Claims

1. Preparation of a TCPP-LSA-J photocatalyst with ultra-long near-infrared absorption and its application in photothermal catalytic production of hydrogen peroxide without sacrificial agent, characterized in that: The steps include: (1) Porphyrin is ultrasonically dispersed in water, and a sodium hydroxide solution is added dropwise to adjust the pH thereof. The porphyrin catalyst is 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP). (2) Preparation of Mg3Al-NO3-LDH: First, 200.0 mL of NaNO3 solution (1.00 mM) was added to a 1000 mL four-necked flask. 200.0 mL of a salt solution containing Mg(NO₃)₂ and Al(NO₃)₃·9H₂O is labeled Solution A, and 200.0 mL of a NaOH solution is labeled Solution B. Both are added dropwise to the flask with vigorous stirring, maintaining the pH of the suspension around 8 throughout the process. After stirring, the mixture is aged at room temperature under a nitrogen atmosphere for 24 hours and then washed with decarbonized water to obtain a Mg₃Al-NO₃-LDH colloid. Once quantified, it is ready for use. (3) TCPP was intercalated into Mg3Al-NO3-LDH using an ion exchange method to prepare TCPP-LDH. Mg3Al-NO3-LDH was added to a TCPP solution at 80°C under a nitrogen atmosphere and ion exchange was performed for 48 hours to obtain TCPP-LDH. The product was then diluted with deionized water and ethanol, and then dispersed in ethanol as a storage solution for further use. (4) Preparation of TCPP-LSA-J: TCPP-LDH was treated in a propionic acid / CH3OH solvent (v:v = 2:3, 3:3, 4:3, 5:3, 6:3, 4:3, 4:5, 4:6) to release ordered π-π TCPP chains, defined as living seeds. The living seeds were sonicated for 0.5–2 h and allowed to grow for 6–24 h to reach the energy state required for stable LSA. During sonication, a mixture of ice and water was used to maintain a constant temperature of 0°C. (5) Preparation of comparative sample TCPP-SA-H: 500 mg of TCPP was fully dissolved in 10.0 mL of 0.50 M KOH aqueous solution at 353 K. 0.10 M HCl aqueous solution was added dropwise using a constant pressure funnel until the pH reached 4. Self-assembled TCPP-SA-H was then synthesized by stirring in a water bath at 353 K for 72 h. After cooling, the mixture was centrifuged and washed multiple times until the pH reached 7. TCPP-SA-H was then collected by filtration and dried in vacuo at 353 K. (6) Disperse 12.50-37.50 mg of the catalyst obtained in step (4) in 50.0-100.0 mL of ultrapure water at a temperature of 20-100° C., continuously introduce oxygen at a flow rate of 25.0-50.0 mL / min, and stir. Simultaneously, irradiate the reaction using a xenon lamp (λ ≥ 420 nm) for a period of time. Filter the resulting reaction product to obtain an aqueous hydrogen peroxide solution.

2. The method according to claim 1, characterized in that The pH of the porphyrin solution in step (1) is 8-9.

3. The method according to claim 1, characterized in that The porphyrin catalyst in step (1) is 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin.

4. The method according to claim 1, wherein The molar ratio of Mg(NO3)2 to Al(NO3)3·9H2O in step (2) is 3:

1.

5. The method according to claim 1, wherein The molar ratio of Mg3Al-NO3-LDH to TCPP in step (3) is 1:

1.

6. The method according to claim 1, characterized in that The volume ratio of propionic acid / CH3OH solvent in step (4) is 4:

5.

7. The method according to claim 1, characterized in that The ultrasonic time described in step (4) is 1 hour.

8. The method according to claim 1, characterized in that The growth time described in step (4) is 12 hours.

9. The method according to claim 1, characterized in that The reaction temperature in step (6) is 80°C.

10. The method according to claim 1, characterized in that The mass of the TCPP-LSA-J and TCPP-SA-H catalysts described in step (6) was 25.00 mg.

11. The method according to claim 1, wherein The amount of ultrapure water used in step (6) is 75.0 mL.

12. The method according to claim 1, characterized in that The oxygen flow rate described in step (6) is 37.5 mL / min.

13. The method according to claim 1, wherein The irradiation time in step (6) is 4 h.

14. The method according to claim 1, wherein In step (5), the filtrate is filtered and then concentrated.

15. The method according to claim 1, wherein Step (6) further comprises centrifuging the solution after the reaction, washing it with ultrapure water, and drying it to recover the porphyrin catalyst.

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