Preparation method and application of sulfonyl-containing defect ternary donor-acceptor organic polymeric material
By using defective ternary donor acceptor organic polymer materials containing sulfone groups, the directional rapid transfer channel of carriers is constructed, and the existing photocatalyst carrier composite and interface dynamics problems are solved, which significantly improves the performance of photocatalytic decomposition of aquatic hydrogen, and ensures the stability and environmental protection of the material.
Patent Information
- Application Number
- CN202510195905.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-21
- Publication Date
- 2025-05-30
AI Technical Summary
The existing photocatalysts have poor results in photocatalyzed decomposition of water to produce hydrogen due to the rapid recombination of carriers, slow interfacial kinetics and limited active sites.
Using defective ternary donor acceptor organic polymeric materials containing sulfone groups, 1,3,6,8-tetrade (4-formaldehyde phenyl)pyrene, 3,7-diaminodibenzo[B,D]thiophene-5,5-dioxide and trialdehyde phlogenetol were used to synthesize materials through Schiff base reaction, and materials with nanosheet-like cluster structures were synthesized by hydrothermal method to increase the active site and hydrophilicity of the material, and to construct a directional rapid transfer channel of carriers.
The electron migration rate is improved, the energy barrier of hydrogen production reaction is reduced, the separation of electron hole pairs is accelerated, and the photocatalytic decomposition of aquatic hydrogen is significantly improved. The material properties are stable, and there is no secondary pollution, and it has good recycling performance.
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Figure CN120059098A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a preparation method of a sulfone group-containing defective ternary donor-acceptor organic polymer material and its application in the direction of photocatalytic water splitting for hydrogen production, belonging to the field of functional technical materials. Background Art
[0002] The energy crisis is one of the two major problems that need to be solved urgently. In the past few decades, many strategies have been proposed to overcome these problems, and semiconductor-based photocatalytic technology is considered to be one of the most promising technologies. Photocatalytic water splitting for hydrogen production can use the inexhaustible solar energy to decompose water to produce hydrogen. The semiconductor photocatalyst absorbs a certain amount of light energy, and the electrons on the valence band are excited to the conduction band to reduce hydrogen protons to generate hydrogen, and the holes remaining on the conduction band undergo oxidation reactions. However, the existing photocatalysts have poor practical application effects due to the rapid recombination of carriers, slow interfacial kinetics, and limited active sites. Therefore, the development of high-performance photocatalysts is still the focus of current research.
[0003] Covalent organic donor-acceptor polymer materials show great potential in the field of photocatalysis due to their unique structures and properties. They are considered promising photocatalyst materials because of their large surface area, high porosity, and adjustable attraction to hydrogen. They have significant thermal / chemical stability and donor-acceptor structures, which can achieve effective electron transfer and light absorption, facilitating the separation and transport of photogenerated carriers. Summary of the Invention
[0004] The present invention discloses a preparation method and application of a sulfone group-containing defective ternary donor-acceptor organic polymer material, which can achieve high-performance photocatalytic water splitting for hydrogen production. The preparation method of the sulfone group-containing defective ternary donor-acceptor organic polymer material includes: using 1,3,6,8-tetrakis(4-formylphenyl)pyrene, 3,7-diaminodibenzo[b,d]thiophene-5,5-dioxide, and phloroglucinol trialdehyde as synthesis precursors, and obtaining the sulfone group-containing defective ternary donor-acceptor organic polymer material through a Schiff base reaction. The material is synthesized by a hydrothermal method, and the obtained material has a nano-sheet cluster structure. The introduction of the sulfone group increases the active sites and hydrophilicity of the material. By introducing a ternary precursor to form a D 1 -A-D 2 double donor-acceptor structure and dual channels located at the defects, constructing a channel for the directional and rapid transfer of carriers, accelerating the separation of electron-hole pairs, increasing the migration rate of electrons, reducing the energy barrier of the hydrogen production reaction, and at the same time the sulfone group increases the hydrophilicity of the material. The material has stable properties, does not produce secondary pollution, and can be recycled, showing excellent photocatalytic water splitting hydrogen production performance.
[0005] First aspect, specifically, the specific preparation process of the sulfone-based defective ternary donor-acceptor organic polymer material (Tpy-3.6DBT-Tp) includes the following steps:
[0006] First step: Add a certain amount of 1,3,6,8-tetrakis(4-formylphenyl)pyrene, 3,7-diaminodibenzo[b,d]thiophene-5,5-dioxide, and phloroglucinol trialdehyde to a mixed solution of ortho-dichlorobenzene and N,N-dimethylacetamide for dissolution, ultrasonicate in a pyrex tube, then add a certain amount of acid catalyst, quickly freeze in liquid nitrogen, and expel air through multiple freeze-pump thaw cycles;
[0007] Second step: Seal the pyrex tube and carry out a hydrothermal reaction to obtain the organic polymer material.
[0008] Further, in the first step, the molar ratio of 1,3,6,8-tetrakis(4-formylphenyl)pyrene, 3,7-diaminodibenzo[b,d]thiophene-5,5-dioxide, and phloroglucinol trialdehyde is 1:7 - 7.2:1.3 - 1.5.
[0009] Further, in the first step, the acid catalyst is 0.5 - 1 mL of acetic acid with a concentration of 6 M.
[0010] Further, in the first step, the volume ratio of ortho-dichlorobenzene to N,N-dimethylacetamide is 1:2.8 - 3.
[0011] Further, in the first step, the dissolution is ultrasonic dissolution, and the time is 10 - 15 min; the number of freeze-pump thaw cycles for degassing with nitrogen is 3 - 5 times, and the pumping time for each time is 0.8 - 1 min.
[0012] Further, in the second step, the hydrothermal temperature is 119 - 121 °C, and the hydrothermal time is 72 - 72.5 h.
[0013] Second aspect, the present invention provides a sulfone-based defective ternary donor-acceptor organic polymer material, and the organic polymer is prepared by the preparation method.
[0014] Third aspect, the present invention claims the application of the above-mentioned sulfone-based defective ternary donor-acceptor organic polymer material in the direction of photocatalytic water splitting for hydrogen production.
[0015] Beneficial technical effects:
[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0017] 1) The present invention for the first time prepared an organic polymer containing defective dual donor-acceptor units. The dual donor-acceptor units form an effective photoinduced electron transfer system, creating an effective directional pathway for electrons to flow from high energy levels to low energy levels. In addition, the introduction of hydrophilic sulfone functional groups establishes strong hydrogen bonds with water molecules, weakening the hydrogen bond interaction between water molecules, thereby enhancing its hydrogen evolution performance.
[0018] 2) The defect structure forms a higher charge density, causing electrons to ultimately accumulate at the sulfone-based active sites, improving the dissociation efficiency of electron-hole pairs, reducing electron recombination, expanding the light absorption spectrum, enhancing the potential of visible light utilization, greatly improving the photocatalytic performance potential, and accelerating the hydrogen production reaction.
[0019] 3) Metal-free materials do not cause secondary pollution and have high application prospects in the field of photocatalytic hydrogen production. Description of the Drawings
[0020] Figure 1 FTIR spectra of the product of Example 1 and the preparation precursor (FTIR spectra of Tpy, DBT, Tp, and Example 1 (Tpy-DBT-Tp));
[0021] Figure 2 Solid state 13 13C NMR spectrum of the product of Example 1;
[0022] Figure 3 SEM images of the products of Example 1 and Comparative Example 1;
[0023] Figure 4 XPS S2p spectra of the samples prepared in Example 1 and the product of Comparative Example 1;
[0024] Figure 5 Hydrogen production rate diagrams of the samples prepared in Example 1 and Comparative Example 1;
[0025] Figure 6 Cyclic performance test diagram of the product of Example 1. Detailed Description of the Invention
[0026] The present invention will be further described below in conjunction with the specific embodiments. However, the protection scope of the present invention is not limited only to the following embodiments. Any non-essential adjustments and modifications made to the present invention based on the above invention content still fall within the protection scope of the present invention.
[0027] Example 1
[0028] Dissolve 0.03 mmol of 1,3,6,8 - tetra(4 - formylphenyl)pyrene, 0.216 mmol of 3,7 - diamino - dibenzo[b,d]thiophene - 5,5 - dioxide, and 0.04 mmol of phloroglucinol tri - aldehyde in a mixed solution of 0.75 mL of N,N - dimethylacetamide and 0.25 mL of o - dichlorobenzene. Ultrasonic for 5 min in a pyrex tube, then add 0.1 mL of acetic acid with a concentration of 6 M. Rapidly freeze the pyrex tube in liquid nitrogen, degas through three freeze - pump thaw cycles, evacuate and seal, and then heat at 120 °C for 3 days. After cooling to room temperature, centrifuge and filter, wash multiple times with acetone and ethanol, and dry at 70 °C for 12 h to obtain the Tpy - 3.6DBT - Tp material.
[0029] Comparative Example 1
[0030] Dissolve 0.03 mmol of 1,3,6,8 - tetra(4 - formylphenyl)pyrene, 0.12 mmol of 3,7 - diamino - dibenzo[b,d]thiophene - 5,5 - dioxide, and 0.04 mmol of phloroglucinol tri - aldehyde in a mixed solution of 0.75 mL of N,N - dimethylacetamide and 0.25 mL of o - dichlorobenzene. Ultrasonic for 5 min in a pyrex tube, then add 0.1 mL of acetic acid with a concentration of 6 M. Rapidly freeze the pyrex tube in liquid nitrogen, degas through three freeze - pump thaw cycles, evacuate and seal, and then heat at 120 °C for 3 days. After cooling to room temperature, centrifuge and filter, wash multiple times with acetone and ethanol, and dry at 70 °C for 12 h to obtain the Tpy - 2DBT - Tp material.
[0031] Figure 1 FTIR spectra of the product of Example 1 and the preparation precursor. It can be seen from Figure 1 that after the reaction, the characteristic absorption peaks of the FT - IR spectra of precursors such as Ph - CHO (1694 cm -1 ) in TPy and N - H (3349 cm -1 ) in BTD decreased sharply. At the same time, a peak of C=N bond (1618 cm -1 ) appeared in the COF, indicating that the imine bond was successfully formed through the Schiff - base reaction and the Tpy - 3.6DBT - Tp material was synthesized.
[0032] Figure 2 Solid - state 13 13C NMR spectrum of the product of Example 1. It can be seen from Figure 2 that the signals of the ketenimine bond at 167 ppm and the C=N bond at 159 ppm exist, indicating that the three precursors reacted successfully to obtain the product Tpy - 3.6DBT - Tp.
[0033] Figure 3SEM images of the products of Example 1 and Comparative Example 1 show that Figure 3 Tpy-3.6DBT-COF has a nanorod-like structure, while Tpy-2DBT-Tp is a needle-like cluster aggregation structure. It can be seen that after changing the acceptor ratio, the structure of the product has changed. The change of the acceptor ratio in the present invention has an important influence on the structure of the product.
[0034] Performance Test
[0035] The method for investigating the simulated pollutant degradation performance provided by the present invention is as follows:
[0036] Weigh 20 mg of each of the products prepared in Example 1 and Comparative Example 1, add 100 mL of 0.1 M ascorbic acid aqueous solution and 900 μL of 0.1 mol / L chloroplatinic acid aqueous solution to the reactor. Use argon as the carrier gas and keep the temperature of the condensed water at 5°C. Use a 300W xenon lamp filtered by a 420nm cutoff filter as the light source. Take samples every 30 minutes and monitor the hydrogen gas collected by a gas chromatograph. The reaction time is 4 hours.
[0037] Figure 4 XPS S2p spectra of the sample prepared in Example 1 and the product of Comparative Example 1. It can be seen from Figure 4 that when the acceptor ratio is increased to 3.6 times that of the donor, the S2p shifts to a lower magnetic field, indicating a decrease in the binding energy and an increase in the electron excitation ability.
[0038] Figure 5 Hydrogen production rate diagrams of the samples prepared in Example 1 and Comparative Example 1. It can be seen from Figure 5 that Tpy-3.6DBT-Tp has better hydrogen production performance than defect-free Tpy-2DBT-Tp, and the hydrogen production amount can reach 3532.8 μmol / g / h, which is 1.9 times that of the defect-free double-donor acceptor polymer Tpy-2DBT-Tp.
[0039] Figure 6 Cyclic performance test diagram of the product of Example 1. It can be seen from Figure 6 that the performance of Tpy-3.6DBT-Tp remains stable after six cycles in the hydrogen production system, and it has good reusability and cyclic stability.
[0040] From the comparison between Example 1 and Comparative Example 1, it can be seen that defects have an impact on the structural morphology of the product and affect the reaction efficiency. The present invention uses specific raw materials, namely 1,3,6,8-tetrakis(4-formylphenyl)pyrene, 3,7-diaminodibenzo[b,d]thiophene-5,5-dioxide and trialdehyde isophthalic acid to prepare the ternary donor-acceptor defect organic polymer material, which produces high catalytic activity, and the photocatalytic hydrogen production yield is 1.9 times that of the product without defects.
[0041] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be recognized that the above description should not be considered as a limitation to the present invention.
Claims
1. A method for preparing a defective ternary donor-acceptor organic polymer material containing a sulfone group, characterized in that: The raw materials of the organic polymer material are 1,3,6,8-tetrakis(4-formaldehydephenyl)pyrene, 3,7-diaminodibenzo [B,D] Thiophene-5,5-dioxide and trialdehyde phloroglucinol; the specific preparation steps are as follows: Step 1: adding a certain amount of 1,3,6,8-tetrakis(4-formaldehydephenyl)pyrene, 3,7-diaminodibenzo[B,D]thiophene-5,5-dioxide and trialdehyde phloroglucinol to a mixed solution of o-dichlorobenzene and N,N-dimethylacetamide to dissolve, ultrasonicating in a pyrex tube, then adding a certain amount of acid catalyst, rapidly freezing in liquid nitrogen, and exhausting air through multiple freeze-pump-thaw cycles; Step 2: Seal the pyrex tube and conduct a hydrothermal reaction to obtain an organic polymer material.
2. The preparation method according to claim 1, characterized in that: In the first step, the molar ratio of 1,3,6,8-tetrakis(4-formaldehydephenyl)pyrene, 3,7-diaminodibenzo[B,D]thiophene-5,5-dioxide and trialdehyde phloroglucinol is 1:7-7.2:1.3-1.
5.
3. The preparation method according to claim 1, characterized in that: In the first step, the acid catalyst is 0.5-1 mL of 6M acetic acid.
4. The preparation method according to claim 1, characterized in that: In the first step, the volume ratio of o-dichlorobenzene to N,N-dimethylacetamide is 1:2.8-3.
5. The preparation method according to claim 1, characterized in that: In the first step, the dissolution is ultrasonic dissolution, and the time is 10-15 minutes; the nitrogen freezing pump thawing cycle degassing number is 3-5 times, and the pumping time each time is 0.8-1 minute.
6. The preparation method according to claim 1, characterized in that: In the second step, the hydrothermal temperature is 119-121°C, and the hydrothermal time is 72-72.5h.
7. A defective ternary donor-acceptor organic polymer material containing a sulfone group, characterized in that: The organic polymer material has dual donor-acceptor units, and the organic framework is prepared by the preparation method according to any one of claims 1 to 6.
8. Application of the defective ternary donor-acceptor organic polymer material containing sulfone groups as claimed in claim 7 in the photocatalytic decomposition of water to produce hydrogen.
9. The use according to claim 8, characterized in that: The defective ternary donor-acceptor organic polymer material containing sulfone groups is used for photocatalytic hydrogen production in a 0.09-0.1M ascorbic acid aqueous solution.