Preparation method and application of D-pi-A type conjugated microporous polymer based on benzothiadiazole and alkynyl benzene unit
Through the preparation method of D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units, the problems of complex hydrogen peroxide production process and serious environmental pollution in the prior art are solved, and efficient and stable photocatalytic preparation of hydrogen peroxide is achieved.
Patent Information
- Application Number
- CN202510034435.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-09
- Publication Date
- 2025-04-11
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The prior art has complex processes, severe environmental pollution, high energy consumption and high cost when producing hydrogen peroxide, and low light absorption, carrier separation and transmission efficiency of photocatalytic materials.
Using the preparation method of D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units, a conjugated microporous polymer with bihexatoms was synthesized through the Sonogashira-Hagihara reaction, and its structure was adjusted to improve the photocatalytic performance.
The performance of photocatalytic hydrogen peroxide preparation is significantly improved, the electron transfer ability and light absorption ability are enhanced, and the material has strong response ability to visible light, stable performance, and can be reused multiple times.
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Figure CN119798621A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of new energy functional materials, and in particular to a preparation method and application of a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units. Background Art
[0002] Hydrogen peroxide is a high-value industrial chemical with strong oxidizing properties and environmental friendliness. It is widely used in pulp bleaching, wastewater treatment, sterilization, chemical synthesis and other fields. With the development of the global economy and the acceleration of industrialization, the demand for hydrogen peroxide continues to increase, and it is estimated that it will increase to 5.7 million tons by 2027. At present, more than 95% of hydrogen peroxide is produced by the anthraquinone method. The process flow of this method is cumbersome and requires multiple complex reaction steps, including hydrogenation, oxidation, extraction, and refining of anthraquinone. At the same time, the anthraquinone method will produce a large amount of organic waste and pollutants, causing serious pollution to the environment, and it has high energy consumption and relatively high production costs.
[0003] Artificial photosynthesis of hydrogen peroxide using sunlight, water and oxygen as raw materials has the advantages of mild reaction, simple operation and no secondary pollution. It can not only realize green and sustainable chemical production, but also realize chemical conversion and energy storage of solar energy, meeting the current major needs of green transformation and development of chemical industry. In recent years, various new photocatalytic materials have emerged, such as covalent organic frameworks, metal organic frameworks, conjugated microporous polymers, etc., providing more choices and possibilities for photocatalytic preparation of hydrogen peroxide. By changing the monomer structure and connection mode of conjugated microporous polymers and introducing different functional groups, the energy band structure, surface properties and active sites of the polymer can be precisely adjusted to improve the photocatalytic performance.
[0004] DA-type conjugated microporous polymer semiconductors composed of alternating electron donors (Donor) and electron acceptors (Acceptor) have become an emerging hot photocatalytic material due to their unique advantages such as wide spectral response range, high stability, and easy-to-control band structure. This paper designs and synthesizes a series of D-π-A-type conjugated microporous polymers composed of different electron donors and electron acceptors, targeting the three factors that restrict the oxygen-hydrogen peroxide conversion process: light absorption, photogenerated carrier separation and transmission, and interfacial reaction. The structure, morphology, hydrogen peroxide production performance, carrier migration and separation behavior are characterized and tested, and studied. Combined with theoretical calculations, the structure-activity relationship between the molecular structure of conjugated microporous polymers and the photocatalytic hydrogen peroxide production performance is preliminarily revealed, and a conjugated microporous polymer with excellent performance for photocatalytic preparation of hydrogen peroxide is obtained. Summary of the invention
[0005] A technical solution adopted by the present invention is: a method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units, the steps of which include: (1) selecting 4,7-dibromobenzo[c][1,2,5]thiadiazole and alkynylbenzene monomers as structural units, selecting toluene and triethylamine as reaction solvents, and stirring the two until they are completely dissolved to obtain a uniform first solution; (2) selecting tetrakis(triphenylphosphine)palladium(0) and cuprous iodide as catalysts, adding them to the first solution, and stirring under nitrogen protection to obtain a second solution; (3) The second solution is subjected to a Sonogashira-Hagihara reaction in an oil bath. After the reaction is completed and naturally cooled to room temperature, the obtained product is washed multiple times and vacuum dried to obtain a D-π-A type conjugated microporous polymer containing a double heteroatom.
[0006] In an embodiment of the present invention, the alkynylbenzene unit in step (1) is changed to adjust the structure of the conjugated microporous polymer, thereby preparing a linear conjugated microporous polymer and a non-linear conjugated microporous polymer.
[0007] In an embodiment of the present invention, in step (1), the mass ratio of tetrakis(triphenylphosphine)palladium(0) to cuprous iodide is 5:(1-5).
[0008] In an embodiment of the present invention, in step (1), the volumes of toluene and triethylamine are 10 mL to 50 mL, respectively.
[0009] In an embodiment of the present invention, the Sonogashira-Hagihara reaction temperature of the second solution is 50 ° C ~ 150 ° C; the reaction time is 1 d ~ 5 d.
[0010] In an embodiment of the present invention, in step (3), the reaction temperature of Sonogashira-Hagihara is 50 °C to 150 °C; and the reaction time is 1 d to 5 d.
[0011] In an embodiment of the present invention, in step (2), the alkynylbenzene monomers are specifically 1,4-diethynylbenzene and 1,3,5-triethynylbenzene, the molar ratio of the 4,7-dibromobenzo[c][1,2,5]thiadiazole to 1,4-diethynylbenzene is 3:(1-5), and the molar ratio of the 4,7-dibromobenzo[c][1,2,5]thiadiazole to 1,3,5-triethynylbenzene is 3:(1-5).
[0012] In an embodiment of the present invention, in step (3), the product is washed 3 to 6 times with dichloromethane, acetone, water and methanol respectively, and dried in a vacuum drying oven for 5 to 20 h, with the drying temperature set at 50 °C to 100 °C.
[0013] In another embodiment of the present invention, a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units is prepared according to the above method.
[0014] In another embodiment of the present invention: the D-π-A type conjugated microporous polymer is used as a photocatalyst in the photocatalytic preparation of hydrogen peroxide.
[0015] The beneficial effects of the present invention are: (1) The preparation method of the conjugated microporous polymer of the present invention is simple, the required raw materials are easily available, and the operation is simple, which is very important for large-scale industrial applications;
[0016] (2) The D-π-A type conjugated microporous polymer described in the present invention uses benzene, benzothiadiazole and acetylene as donor units, acceptor units and π crosslinkers, respectively, to overcome the problem of easy recombination of photogenerated electrons and holes, because the relatively separated redox centers of the D-π-A type conjugated microporous polymer promote the effective separation and rapid transfer of photogenerated electrons and holes, significantly improving the performance of photocatalytic preparation of hydrogen peroxide;
[0017] (3) The conjugated microporous polymer of the present invention can further improve the separation efficiency of the generated charge carriers, because the nonlinear structure has a higher degree of conjugation, which prevents the charge transfer along the polymer chain for recombination, giving the D-π-A type conjugated microporous polymer a stronger driving force, thereby enhancing the electron transfer ability and light absorption ability, and showing significantly enhanced photocatalytic performance;
[0018] (4) The conjugated microporous polymer described in the present invention is a catalytic material with strong visible light response ability, high photocatalytic preparation of hydrogen peroxide effect, stable performance, and can be reused multiple times. It has good application prospects in the field of new energy. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which: Figure 1 is a structural diagram of a conjugated microporous polymer of an embodiment; Figure 2is a solid nuclear magnetic resonance (NMR) spectrum of the conjugated microporous polymer of the embodiment; Figure 3 is the Fourier transform infrared (FT-IR) spectrum of the conjugated microporous polymer of the embodiment; Figure 4 This is a photocatalytic effect diagram of the conjugated microporous polymer prepared in Example for preparing hydrogen peroxide; Figure 5 This is a diagram showing the cyclic effect of photocatalytic preparation of hydrogen peroxide by the conjugated microporous polymer prepared in the example. DETAILED DESCRIPTION
[0020] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0021] See also Figure 1-5 , an embodiment of the present invention includes: a method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units, the steps of which include: (1) selecting 4,7-dibromobenzo[c][1,2,5]thiadiazole and alkynylbenzene monomers as structural units, selecting toluene and triethylamine as reaction solvents, and stirring the two until they are completely dissolved to obtain a uniform first solution; (2) selecting tetrakis(triphenylphosphine)palladium(0) and cuprous iodide as catalysts, adding them to the first solution, and stirring under nitrogen protection to obtain a second solution; (3) The second solution is subjected to a Sonogashira-Hagihara reaction in an oil bath. After the reaction is completed and naturally cooled to room temperature, the obtained product is washed multiple times and vacuum dried to obtain a D-π-A type conjugated microporous polymer containing a double heteroatom.
[0022] In an embodiment of the present invention, the alkynylbenzene unit described in step (1) is changed to adjust the structure of the conjugated microporous polymer to prepare a linear conjugated microporous polymer and a non-linear conjugated microporous polymer. In an embodiment of the present invention, in step (1), the mass ratio of tetrakis(triphenylphosphine)palladium(0) to cuprous iodide is 5:(1-5).
[0023] In an embodiment of the present invention, in step (1), the volumes of toluene and triethylamine are 10 mL to 50 mL, respectively.
[0024] In an embodiment of the present invention, the Sonogashira-Hagihara reaction temperature of the second solution is 50 ° C ~ 150 ° C; the reaction time is 1 d ~ 5 d.
[0025] In an embodiment of the present invention, in step (3), the reaction temperature of Sonogashira-Hagihara is 50 °C to 150 °C; and the reaction time is 1 d to 5 d.
[0026] In an embodiment of the present invention, in step (2), the alkynylbenzene monomers are specifically 1,4-diethynylbenzene and 1,3,5-triethynylbenzene, the molar ratio of the 4,7-dibromobenzo[c][1,2,5]thiadiazole to 1,4-diethynylbenzene is 3:(1-5), and the molar ratio of the 4,7-dibromobenzo[c][1,2,5]thiadiazole to 1,3,5-triethynylbenzene is 3:(1-5).
[0027] In an embodiment of the present invention, in step (3), the product is washed 3 to 6 times with dichloromethane, acetone, water and methanol respectively, and dried in a vacuum drying oven for 5 to 20 h, with the drying temperature set at 50 °C to 100 °C. Example
[0028] The preparation method of D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units comprises the following specific steps: First, 3 mmol of 4,7-dibromobenzo[c][1,2,5]thiadiazole was added to 30 mL of toluene and 30 mL of triethylamine and stirred until completely dissolved. Then, 3 mmol of 1,4-diethynylbenzene was added to the above solution and stirred for 30 min to obtain a uniform first solution. Subsequently, 100 mg of tetrakis(triphenylphosphine)palladium(0) and 40 mg of cuprous iodide were added and nitrogen protection was performed to obtain a second solution. Finally, the obtained second solution was reacted in an oil bath at 80 °C for 3 d. After the reaction was completed and naturally cooled to room temperature, the product was washed 3 times with dichloromethane, acetone, water and methanol respectively, and finally dried in a vacuum drying oven at 60 °C for 12 h to obtain a linear conjugated microporous polymer.
[0029] Attached Figure 1 , Figure 2 and Figure 3 They are the structural diagram, NMR spectrum and FT-IR spectrum of the linear conjugated microporous polymer, which can be used to judge the successful preparation of the linear conjugated microporous polymer. Example
[0030] The preparation method of D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units comprises the following specific steps: First, 3 mmol of 4,7-dibromobenzo[c][1,2,5]thiadiazole was added to 30 mL of toluene and 30 mL of triethylamine and stirred until completely dissolved. Then, 2 mmol of 1,3,5-triethynylbenzene was added to the above solution and stirred for 30 min to obtain a uniform first solution. Subsequently, 100 mg of tetrakis(triphenylphosphine)palladium(0) and 40 mg of cuprous iodide were added and nitrogen protection was performed to obtain a second solution. Finally, the obtained second solution was reacted in an oil bath at 80 °C for 3 d. After the reaction was completed and naturally cooled to room temperature, the product was washed 3 times with dichloromethane, acetone, water and methanol respectively, and finally dried in a vacuum drying oven at 60 °C for 12 h to obtain a nonlinear conjugated microporous polymer.
[0031] Attached Figure 1 , Figure 2 and Figure 3 They are the structural diagram, NMR spectrum and FT-IR spectrum of the nonlinear conjugated microporous polymer, which can be used to judge the successful preparation of the nonlinear conjugated microporous polymer. Example
[0032] Photocatalytic preparation of hydrogen peroxide, the specific steps are as follows: 10 mg of the catalyst prepared in Examples 1 and 2 were respectively dispersed in 50 mL of aqueous solution and stirred for 30 min to obtain a uniform reaction solution. At the same time, the temperature of the photocatalytic reaction system was maintained at room temperature using a condensation circulation system. Finally, a 300 W xenon lamp was used as a light source. The photocatalytic preparation of hydrogen peroxide was continued for 1 h under stirring conditions. Samples were collected every 15 min, and the amount of hydrogen peroxide produced under light was quantitatively detected by a UV-visible spectrophotometer.
[0033] Attached Figure 4 The effect diagram of the prepared conjugated microporous polymer photocatalytic preparation of hydrogen peroxide. It can be seen from the figure that the efficiency of non-linear conjugated microporous polymer photocatalytic preparation of hydrogen peroxide is significantly higher than that of linear conjugated microporous polymer.
[0034] Attached Figure 5 This is a diagram showing the cyclic effect of nonlinear conjugated microporous polymer photocatalytic preparation of hydrogen peroxide. As can be seen from the figure, the material still shows a high hydrogen peroxide yield after 5 uses, indicating that it has good cyclic stability and potential application value.
[0035] The beneficial effects of the preparation method of the D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units of the present invention are: (1) The preparation method of the conjugated microporous polymer described in the present invention is simple, the required raw materials are easily available, and the operation is simple, which is convenient for large-scale industrial application.
[0036] (2) The D-π-A type conjugated microporous polymer described in the present invention uses benzene, benzothiadiazole and acetylene as donor units, acceptor units and π cross-linking agents, respectively, to overcome the problem of easy recombination of photogenerated electrons and holes. The relatively separated redox centers of the D-π-A type conjugated microporous polymer promote the effective separation and rapid transfer of photogenerated electrons and holes, thus significantly improving the performance of photocatalytic preparation of hydrogen peroxide.
[0037] (3) The conjugated microporous polymer described in the present invention can further improve the separation efficiency of generated carriers because the nonlinear structure has a higher degree of conjugation, which prevents the charge transfer along the polymer chain for recombination, giving the D-π-A type conjugated microporous polymer a stronger driving force, thereby enhancing the electron transfer ability and light absorption ability, and showing significantly enhanced photocatalytic performance.
[0038] (4) The conjugated microporous polymer described in the present invention is a catalytic material with strong visible light response ability, high photocatalytic preparation of hydrogen peroxide effect, stable performance, and can be reused multiple times. It has good application prospects in the field of new energy.
[0039] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.
Claims
1. A method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units, characterized in that: The following steps are involved: (1) selecting 4,7-dibromobenzo[c][1,2,5]thiadiazole and alkynylbenzene monomers as structural units, selecting toluene and triethylamine as reaction solvents, and stirring the two until they are completely dissolved to obtain a uniform first solution; (2) selecting tetrakis(triphenylphosphine)palladium(0) and cuprous iodide as catalysts, adding them to the first solution, and stirring under nitrogen protection to obtain a second solution; (3) The second solution is subjected to a Sonogashira-Hagihara reaction in an oil bath. After the reaction is completed and naturally cooled to room temperature, the obtained product is washed multiple times and vacuum dried to obtain a D-π-A type conjugated microporous polymer containing a double heteroatom.
2. The method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units according to claim 1, characterized in that: The alkynylbenzene unit described in step (1) is changed to adjust the structure of the conjugated microporous polymer, thereby preparing a linear conjugated microporous polymer and a non-linear conjugated microporous polymer.
3. The method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units according to claim 1, characterized in that: In step (1), the mass ratio of tetrakis(triphenylphosphine)palladium(0) to cuprous iodide is 5:(1-5).
4. The method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units according to claim 1, characterized in that: In step (1), the volumes of toluene and triethylamine are 10 mL to 50 mL, respectively.
5. The method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units according to claim 1, characterized in that: The Sonogashira-Hagihara reaction temperature of the second solution is 50 ° C ~ 150 ° C; the reaction time is 1 d ~ 5 d.
6. The method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units according to claim 1, characterized in that: In step (3), the reaction temperature of Sonogashira-Hagihara is 50 °C to 150 °C; and the reaction time is 1 d to 5 d.
7. The method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units according to claim 1, characterized in that: In step (2), the alkynylbenzene monomers are specifically 1,4-diethynylbenzene and 1,3,5-triethynylbenzene, the molar ratio of the 4,7-dibromobenzo[c][1,2,5]thiadiazole to 1,4-diethynylbenzene is 3:(1-5), and the molar ratio of the 4,7-dibromobenzo[c][1,2,5]thiadiazole to 1,3,5-triethynylbenzene is 3:(1-5).
8. The method for preparing a D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units according to claim 1, characterized in that: In step (3), the product is washed 3 to 6 times with dichloromethane, acetone, water and methanol respectively, and dried in a vacuum drying oven for 5 to 20 h, with the drying temperature set at 50 °C to 100 °C.
9. A D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units prepared according to the method of any one of claims 1 to 8.
10. The D-π-A type conjugated microporous polymer based on benzothiadiazole and alkynylbenzene units according to claim 9, characterized in that: The D-π-A type conjugated microporous polymer is used as a photocatalyst in the photocatalytic preparation of hydrogen peroxide.