An electron donor-acceptor polymer and a preparation method and application thereof

Abstract

The present application relates to the field of photocatalytic material and virus inactivation, and particularly relates to a preparation method and application of a high-efficiency photocatalytic electron donor-acceptor polymer. The present application provides an electron donor-acceptor polymer, which significantly expands the light absorption range to the visible light region, promotes the separation and transfer of photo-generated charges; at the same time, the highly asymmetric dipole structure enhances the built-in electric field, which further promotes the electron transfer and reduces the carrier recombination, thereby greatly improving the photocatalytic efficiency, promoting the generation of reactive oxygen species, achieving efficient killing of viruses, and providing an efficient, safe and sustainable new material technical solution for the prevention and control of aquaculture viruses.

Description

Technical Field

[0001] This application relates to the fields of photocatalytic materials and disinfection technology, and in particular to an electron donor-acceptor polymer and its preparation method and application. Background Technology

[0002] As the world's largest aquaculture producer, China has witnessed continuous expansion of its aquaculture scale and increasing intensification. However, this high-density, intensive aquaculture model has brought a series of severe challenges: the accumulation of feed and manure, along with suitable temperature and nutrient conditions, provides breeding grounds for harmful microorganisms, easily leading to diseases; the high-density aquaculture environment further exacerbates the risk of transmission and infection. This makes infections caused by viral, bacterial, and parasitic pathogens a major threat to the economic and industrial development of aquaculture.

[0003] Traditional physical / chemical disinfection methods (such as ultraviolet irradiation, ozone oxidation, and chlorine disinfection) have significant drawbacks in practical applications: ultraviolet light is prone to blind spots; ozone and chlorine disinfectants, while inactivating viruses, can negatively impact farmed animals; and chlorine disinfectants produce carcinogenic byproducts such as trihalomethanes during use, posing environmental and food safety risks. Furthermore, these methods struggle to maintain effective concentrations in farming systems, failing to achieve long-term, continuous virus inactivation and often resulting in the dilemma of incomplete disinfection or excessive toxicity.

[0004] To address the problems of traditional disinfection methods, photocatalytic disinfection technology has attracted widespread attention as an emerging and highly promising disinfection approach. Using sunlight as an energy source and oxygen and water as raw materials, it generates active species through photocatalytic reactions, effectively inactivating viruses and bacteria. It boasts advantages such as being environmentally friendly and producing no secondary pollution, making it highly compatible with the green governance needs of aquaculture water bodies. However, existing photocatalysts still have the following pressing problems: First, they primarily respond to ultraviolet light, but ultraviolet light accounts for less than 5% of the solar spectrum, resulting in extremely low visible light utilization and difficulty in achieving sustained virus inactivation; second, photogenerated electrons and holes readily recombine rapidly, causing a large amount of light energy to dissipate as heat, making it impossible to efficiently kill high concentrations of viruses in water bodies within a short time.

[0005] Therefore, there is an urgent need to develop a photocatalytic disinfection technology that can significantly improve the utilization efficiency of visible light and reduce the recombination of photogenerated electrons and holes. Summary of the Invention

[0006] The primary objective of this invention is to overcome the problems of low visible light utilization efficiency and rapid carrier recombination in existing photocatalytic disinfection methods, thereby achieving continuous and efficient killing of viruses in water, and to provide an electron donor-acceptor polymer.

[0007] Another object of the present invention is to provide a method for preparing the above-mentioned electron donor-acceptor polymer.

[0008] Another object of the present invention is to provide the application of the above-mentioned electron donor-acceptor polymer in photocatalysis.

[0009] Another object of the present invention is to provide the application of the above-mentioned electron donor-acceptor polymer in the field of killing aquaculture viruses.

[0010] The above-mentioned objective of the present invention is achieved through the following technical solution: This invention protects an electron donor-acceptor polymer having the following chemical structural formula:

[0011] Where the degree of polymerization n > 1, For electron donor units, For electronic bridge, For electricity Sub-receptor unit; The electron donor unit is:

[0012] The electronic bridge is:

[0013] The electron acceptor unit is: or

[0014] J represents the site where the electron donor connects to the electron bridge, K represents the site where the electron acceptor connects to the electron bridge, p represents the site where the electron bridge connects to the electron acceptor unit, and m represents the site where the electron bridge connects to the electron donor unit.

[0015] The electron donor-acceptor polymer provided by this invention can efficiently generate reactive oxygen species under light irradiation. Its strong oxidizing properties can directly attack the cell structure and biomolecules of microorganisms, achieving broad-spectrum and highly efficient disinfection. This performance stems from the synergistic effect of multiple molecular designs: First, the D–π–A type conjugated polymer constructed using tetraphenylethylene as the electron donor, alkynyl groups as the conjugated bridge, and phenanthrenequinone as the electron acceptor significantly reduces the material's band gap and promotes a red shift of the absorption edge through strong intramolecular charge transfer effects between the donor and acceptor and π-electron delocalization induced by the alkynyl bridge; simultaneously, the strong electron-withdrawing carbonyl group of the phenanthrenequinone unit interacts with the n–π... *The transition further enhances the long-wavelength light response, effectively extending the material's light absorption range into the visible light region, thereby improving solar energy utilization and photocatalytic performance. Secondly, the electron affinity difference between the tetraphenylethylene donor and the phenanthrenequinone acceptor induces a strong intramolecular charge transfer effect and a built-in electric field, driving photogenerated electrons to migrate directionally from the donor to the acceptor, achieving efficient exciton dissociation and spatial separation. The alkynyl bridge enhances π-electron delocalization and orbital coupling, providing an efficient transport channel for carrier migration. Simultaneously, the reversible redox properties of the phenanthrenequinone unit facilitate electron capture and transport, effectively extending electron lifetime and inhibiting electron-hole recombination. These three factors ultimately achieve efficient separation and rapid migration of photogenerated carriers, enabling more photogenerated electrons to participate in surface oxygen reduction reactions, accelerating oxygen activation, and promoting the continuous generation of reactive oxygen species. Reactive oxygen species exert multi-target synergistic damage on viruses through non-specific oxidation, including inducing lipid peroxidation to destroy the viral envelope structure, oxidizing surface proteins leading to loss of receptor binding capacity, and attacking viral RNA / DNA to induce genetic material breakage and inactivation, inhibiting viral adsorption, infection, and replication processes. In summary, this unique molecular design enables the electron donor-acceptor polymer to extend light absorption into the visible light region, promote photogenerated charge separation and transfer, reduce carrier recombination, and achieve continuous and efficient elimination of viruses in water, thus showing broad application prospects.

[0016] Furthermore, the degree of polymerization is 2 to 100,000.

[0017] This invention protects a method for preparing the above-mentioned electron donor-acceptor polymer, comprising the following steps: S1. Tetra(4-ethynylbenzene)ethylene, phenanthrenequinone, palladium catalyst, co-catalyst, and organic solvent are mixed and deoxygenated under an inert atmosphere.

[0018] S2. Heating under an inert atmosphere causes a reaction that produces a precipitate.

[0019] S3. Collect the precipitate, wash it, and dry it to obtain an electron donor-acceptor polymer.

[0020] Further, in step S1, the amount of tetra(4-ethynylphenyl)ethylene used is 0.001~10000 mmol.

[0021] Further, in step S1, the phenanthrenequinone is 2,7-dibromophenanthrenequinone and / or 3,6-dibromophenanthrenequinone.

[0022] Furthermore, in step S1, the amount of 2,7-dibromophenanthroline and / or 3,6-dibromophenanthroline is 0.001~10000 mmol.

[0023] Further, in step S1, the palladium catalyst includes one or more of elemental palladium, palladium salts, and palladium complexes.

[0024] Furthermore, the palladium salt is palladium acetate and / or palladium chloride.

[0025] Furthermore, the palladium complex includes one or more of bis(triphenylphosphine)palladium dichloride, triphenylphosphine palladium, and bis(dibenzoyldiimide)palladium.

[0026] Furthermore, the amount of palladium catalyst used is 0.001 mmol to 100 mmol. Further, in step S1, the co-catalyst includes one or more of copper co-catalyst, phosphine ligand, and amine.

[0027] Furthermore, the copper co-catalyst is one or more of cuprous iodide, cuprous bromide, cuprous chloride, and nano-copper.

[0028] Furthermore, the phosphine ligand is one or more of triphenylphosphine, 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl, and bis(2-diphenylphosphine) ether.

[0029] Furthermore, the amine is N,N′-dimethylethylenediamine.

[0030] Furthermore, the amount of the co-catalyst is 0.001 mmol to 100 mmol.

[0031] Further, in step S1, the solvent includes one or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, tetrahydrofuran, dioxane, triethylamine, diisopropylethylamine, toluene, xylene, pyridine, or a potassium carbonate / water system.

[0032] Furthermore, the amount of solvent used is 1 to 100 equivalents.

[0033] Furthermore, in step S1, the reaction system is deoxygenated under an inert atmosphere by bubbling inert gas for 10-60 minutes and / or by freezing-vacuuming-thawing cycle.

[0034] Furthermore, in step S2, the heating can be selected from one or more of conventional heating, microwave-assisted heating, or oil bath temperature control.

[0035] Specifically, the heating temperature is 25~250 ℃.

[0036] Furthermore, in step S2, the reaction time is 0.5 to 200 h.

[0037] Specifically, in step S3, the washing process employs a Soxhlet extractor.

[0038] Furthermore, the washing solvent may be one or more of methanol, acetone, dichloromethane, and chloroform.

[0039] Furthermore, the washing time is 0.5 to 200 hours.

[0040] Specifically, in step S3, the drying is vacuum drying.

[0041] Furthermore, the drying temperature is 20~300 ℃.

[0042] This invention protects the application of the above-mentioned electron donor-acceptor polymer in photocatalysis.

[0043] This invention protects the application of the above-mentioned electron donor-acceptor polymer in the field of killing aquatic viruses.

[0044] Compared with the prior art, the beneficial effects of the present invention are: This invention provides an electron donor-acceptor polymer, in which an alkynyl group serves as an electron bridge connecting the electron donor and acceptor units. The electron donor unit is tetraphenylethylene, and the electron acceptor unit is phenanthrenequinone. Through the molecular design of this electron donor-acceptor (D–A) conjugated polymer, the light absorption range is significantly extended into the visible light region, improving solar energy utilization and photocatalytic performance. Simultaneously, the highly asymmetric dipole structure enhances the built-in electric field, which further promotes electron transfer and reduces carrier recombination, thereby significantly improving photocatalytic efficiency and achieving highly efficient virus killing, with a virus inactivation rate exceeding 99% within 50 minutes of irradiation. Attached Figure Description

[0045] Figure 1 The images show the solid-state UV-Vis diffuse reflectance spectra of the polymers from Examples 1 and 2.

[0046] Figure 2 The following are fluorescence spectra of the polymers from Examples 1 and 2.

[0047] Figure 3 The images show the electron paramagnetic resonance spectra of the polymers from Examples 1 and 2.

[0048] Figure 4 The graph shows the photocatalytic virus inactivation performance of the polymers in Examples 1 and 2. Detailed Implementation

[0049] To more clearly and completely describe the technical solution of the present invention, the present invention is further described in detail below through specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention. Various changes can be made within the scope of the claims of the present invention. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in this technical field.

[0050] Example 1: Preparation of an electron donor-acceptor polymer S1. In a dry round-bottom flask, add 20 mmol of 2,7-dibromophenanthroline and 10 mmol of tetra(4-ethynylbenzene)ethylene in sequence, followed by 1 mmol of bis(triphenylphosphine)palladium dichloride, 1 mmol of cuprous iodide, 50 mL of toluene, and 50 mL of triethylamine. The reaction system is bubbled with inert gas for 30 minutes to remove oxygen.

[0051] S2. After deoxidation, the reaction was carried out in an oil bath at 60 °C under an inert atmosphere with stirring for 72 h.

[0052] S3. After the reaction was complete, the precipitate was collected and washed continuously for 48 h using a Soxhlet extractor with methanol:chloroform = 1:1 as the washing agent. The final product was dried under vacuum at 60 °C to obtain the target compound TPE-2,7PQ, with a polymer degree of polymerization n = 2~100000.

[0053] The polymer structure is shown in the figure below:

[0054] Example 2: Preparation of an electron donor-acceptor polymer S1. In a dry round-bottom flask, add 20 mmol of 3,6-dibromophenanthroline and 10 mmol of tetra(4-ethynylbenzene)ethylene in sequence, followed by 1 mmol of bis(triphenylphosphine)palladium dichloride, 1 mmol of cuprous iodide, 50 mL of toluene, and 50 mL of triethylamine. The reaction system is bubbled with inert gas for 30 minutes to remove oxygen.

[0055] S2. After deoxidation, the reaction was carried out in an oil bath at 60 °C under an inert atmosphere with stirring for 72 h.

[0056] S3. After the reaction was complete, the precipitate was collected and washed continuously for 48 h using a Soxhlet extractor with methanol:chloroform = 1:1 as the washing agent. The final product was dried under vacuum at 60 °C to obtain the target compound TPE-3,6PQ, with a polymer degree of polymerization n = 2~100000.

[0057] The polymer structure is shown in the figure below:

[0058] Physicochemical properties of electron donor and acceptor polymers in Experimental Example 1 and Example 2.

[0059] 1. Absorption spectrum The absorption spectra of the electron donor-acceptor polymers TPE-2,7PQ and TPE-3,6PQ from Examples 1 and 2 were measured using a UV-Vis-NIR spectrophotometer. The results are as follows: Figure 1 As shown, the polymer of this invention exhibits excellent absorption capacity in the wavelength range of 200-800 nm, indicating that its photoresponse range extends from the ultraviolet region to the visible light region. This superior light absorption performance provides a solid foundation for achieving efficient photocatalytic activity, giving it greater potential and advantages in photocatalytic applications.

[0060] 2. Fluorescence spectrum The electron donor-acceptor polymers TPE-2,7PQ and TPE-3,6PQ from Examples 1 and 2 were subjected to fluorescence spectroscopy. The results are as follows: Figure 2 As shown, the polymer exhibits weak fluorescence emission intensity. Since fluorescence emission originates from the recombination of photogenerated electrons and holes, the lower fluorescence intensity directly indicates a decrease in the recombination rate of photogenerated carriers. This implies that the polymer experiences reduced photogenerated carrier recombination and higher charge separation efficiency, thereby significantly improving the charge separation efficiency and photocatalytic activity of the catalyst.

[0061] 3. Generation of reactive oxygen species Electron paramagnetic resonance (EPR) tests were performed on the electron donor-acceptor polymers TPE-2,7PQ and TPE-3,6PQ from Examples 1 and 2 using an electron paramagnetic resonance spectrometer. The results are as follows: Figure 3 As shown, after 1 min of visible light irradiation, a significant ·O2 molecule appeared in the electron paramagnetic resonance (EPR) spectrum. and 1 The characteristic O2 signal peak indicates that the polymer of this invention can efficiently convert light energy into chemical energy and generate reactive oxygen species under visible light excitation. This lays a crucial foundation for the polymer to achieve rapid photocatalytic virus inactivation. Chinese patent CN116178678A discloses a somewhat similar electron donor-acceptor polymer, but it uses different electron acceptor units. Although its electron bridge and electron acceptor can act as active sites for oxygen reduction after receiving electrons, it does not disclose whether reactive oxygen species such as O2 are present. and 1 O2 is generated, therefore, it fails to disclose a virus-killing effect similar to that of this application.

[0062] 4. Photocatalytic virus inactivation performance Nucleic acid quantification was performed on the electron donor-acceptor polymers TPE-2,7PQ and TPE-3,6PQ from Examples 1 and 2 using a real-time quantitative polymerase chain reaction (qPCR) instrument. The results are as follows: Figure 4 As shown. A xenon lamp (CEL-HXF300) was used as the light source, and a cutoff filter (λ>420 nm) was used to provide an average light intensity of 50 mW·cm. –2 Visible light irradiation. Under these conditions, the polymer of the present invention reacts with an initial concentration of 10... 7 The copies / mL of iridovirus exhibited highly efficient photocatalytic inactivation activity. Among them, TPE-2,7PQ achieved a virus inactivation rate of over 99% within 50 min of irradiation, while TPE-3,6PQ achieved a virus inactivation rate of over 99% within 90 min of irradiation.

[0063] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. An electron donor-acceptor polymer, said electron donor-acceptor polymer having the following chemical structural formula: in, Degree of aggregation n > 1 For electron donor units, For electronic bridge, It is an electron acceptor unit; The electron donor unit is: The electronic bridge is: The electron acceptor unit is: or J represents the site where the electron donor connects to the electron bridge, K represents the site where the electron acceptor connects to the electron bridge, p represents the site where the electron bridge connects to the electron acceptor unit, and m represents the site where the electron bridge connects to the electron donor unit.

2. The electron donor-acceptor polymer according to claim 1, characterized in that, n=2~100000。 3. The method for preparing the electron donor-acceptor polymer according to claim 1, characterized in that, Includes the following steps: S1. Tetra(4-ethynylbenzene)ethylene, phenanthrenequinone, palladium catalyst, co-catalyst, and organic solvent are mixed and deoxygenated under an inert atmosphere; S2. Heating under an inert atmosphere causes a reaction that produces a precipitate; S3. Collect the precipitate, wash it, and dry it to obtain the electron donor-acceptor polymer.

4. The preparation method according to claim 3, characterized in that, In step S1, the palladium catalyst includes one or more of elemental palladium, palladium salts, and / or palladium complexes.

5. The preparation method according to claim 3, characterized in that, In step S1, the cocatalyst includes one or more of copper cocatalysts, phosphine ligands, and / or amines.

6. The preparation method according to claim 3, characterized in that, In step S1, the solvent includes one or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, tetrahydrofuran, dioxane, triethylamine, diisopropylethylamine, toluene, xylene, pyridine, or a potassium carbonate / water system.

7. The preparation method according to claim 3, characterized in that, In step S1, the reaction system is deoxygenated under an inert atmosphere by bubbling inert gas for 10–60 minutes and / or by freezing-vacuuming-thawing cycle.

8. The preparation method according to claim 3, characterized in that, In step S3, the washing solvent is selected from one or more of methanol, acetone, dichloromethane or chloroform.

9. The application of the electron donor-acceptor polymers according to claims 1 to 8 in photocatalysis.

10. The application of the electron donor-acceptor polymer according to claims 1 to 8 in the field of killing viruses in aquatic aquaculture.

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