Polymer electrolyte material photoanode and preparation method and application thereof

Abstract

The invention discloses a polymer electrolyte material photoanode and a preparation method and application thereof, and belongs to the technical field of photoelectrocatalytic water decomposition oxygen evolution materials. According to the preparation method disclosed by the invention, the polymer is subjected to structural design, so that the retention time of a catalyst on a photoanode is effectively prolonged, and the stability of photoelectrocatalysis is improved; meanwhile, a hydrophobic structure of a long alkyl chain is introduced, so that the retention time of the catalyst on a photoanode is prolonged, and the stability of photoelectrocatalysis is improved; through non-intermolecular interaction between long alkyl chains, a traditional complex synthesis process is simplified by adopting a self-assembly strategy, and meanwhile, the photoelectrocatalysis performance of the polymer electrolyte material photoanode is further optimized by precisely regulating and controlling the composition of the catalyst and the photosensitizer.

Description

Technical Field

[0001] The invention belongs to the technical field of photoelectrocatalytic water decomposition and oxygen evolution materials, and specifically relates to a polymer electrolyte material photoanode and a preparation method and application thereof. Background Art

[0002] Artificial photosynthesis, as a cutting-edge technology that simulates the photosynthesis process in nature, has the core vision of efficiently capturing and utilizing sunlight energy and converting it into solar fuels that can be directly stored and transported. Driven by this grand goal, fuel-sensitized photoelectrochemical cells (DSPECs) have emerged as an important strategy in exploring the path of artificial photosynthesis. DSPEC technology cleverly uses photosensitizers as a medium for energy conversion to directly convert captured solar energy into chemical energy. This mechanism not only revolutionizes the way of energy conversion, but also provides new ideas for the development of sustainable energy. As a key component of the DSPEC system, the dye-sensitized photoanode has a sophisticated structural design. It is usually supported by a conductive glass substrate, semiconductor materials as a bridge for electron transmission, and carefully selected photosensitizers and water oxidation catalysts. This combination gives the photoanode a wide spectral absorption capacity. Compared with traditional inorganic semiconductor photoanodes, dye-sensitized photoanodes show a more superior spectral response range and a slower carrier recombination rate, thereby achieving a significant improvement in energy conversion efficiency, which has attracted widespread attention in the energy materials science community. However, although dye-sensitized photoanodes have many advantages in theory, they face considerable challenges in practical applications. In particular, the adsorption and desorption process of photosensitizers and catalysts on the surface of the photoanode often becomes a key factor restricting the long-term stability of the device and the maintenance of the photocurrent density. The instability of these surface dynamic processes causes the performance of the photoanode to decline rapidly over time and the photocurrent density to decay sharply, which seriously hinders the commercialization of DSPEC technology. Therefore, how to optimize the interfacial interaction between photosensitizers and catalysts and improve the stability of the device has become a core issue that needs to be urgently solved in the current research field of dye-sensitized photoelectrochemical cells.

[0003] In order to improve the stability of the photoanode, researchers are constantly exploring new strategies. Among them, the introduction of long hydrophobic alkyl chains and the use of atomic layer deposition (ALD) technology are two common methods. The introduction of long hydrophobic alkyl chains is intended to enhance the stability of the photosensitizer and reduce its desorption on the surface of the photoanode; while the ALD technology entraps the photosensitizer by depositing oxides or polymer compounds to protect it from environmental influences. However, these methods face many challenges in practical applications, such as complex chemical synthesis steps, high equipment costs, and possible reductions in electron transfer rates, all of which restrict the realization of efficient DSPEC systems. Therefore, it is urgent to design novel electrode structures and assembly strategies in order to significantly improve the stability of the photoanode without sacrificing the efficiency of DSPEC. This has important theoretical significance and practical application value for optimizing the structure of dye-sensitized photoanodes and further improving the photoelectrocatalytic water oxidation performance.

[0004] It has been reported that phosphonic acid groups have strong binding affinity for metal oxides and high electron injection efficiency. However, molecular modified electrodes containing only a single phosphonic acid group usually have poor stability, especially when the pH value is higher than 6. Summary of the invention

[0005] The purpose of the present invention is to provide a polymer electrolyte material photoanode and a preparation method and application thereof, so as to solve the technical problem of poor photoelectrocatalytic performance caused by the unstable structure of the existing photoanode.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention discloses a method for preparing a photoanode of a polymer electrolyte material, comprising the following steps: The copolymer is subjected to a hydrolysis reaction to obtain a hydrolyzed polymer; the hydrolyzed polymer is subjected to a coordination reaction with a catalyst to obtain a polymer grafted with the catalyst; The polymer grafted with the catalyst is dissolved in a solvent to obtain a mixed solution; The core-shell structure electrode is coated on the substrate and then immersed in the mixed solution to obtain an assembled electrode with the catalyst anchored on the surface; The assembled electrode with the catalyst anchored on the surface is placed in a photosensitizer solution to obtain a polymer electrolyte material photoanode.

[0007] Furthermore, the chemical structural formula of the hydrolyzed polymer is as follows: ; Where: R is C 10 H 21 Long alkyl chains.

[0008] Furthermore, the preparation method of the copolymer is: Pyridin-4-yl 2-methylprop-2-enoate, diethyl {[(2-methyl-1-oxyylideneprop-2-enyl)oxy]methyl}phosphonate and decyl 2-methylprop-2-enoate were dissolved in THF, subjected to freeze-pump-thaw cycles under a nitrogen atmosphere, and then heated to reflux to obtain a mixture; The mixture is cooled and concentrated to obtain a crude product; n-hexane copolymer is added to the crude product for reaction to obtain a copolymer; The usage ratio of the 2-methylprop-2-enoic acid pyridin-4-yl ester, {[(2-methyl-1-oxyylideneprop-2-enyl)oxy]methyl}phosphonic acid diethyl ester, 2-methylprop-2-enoic acid decyl ester and THF is (40-50) mg: (10-30) mg: (30-40) mg: (7-15) mL; The number of freeze-pump-thaw cycles is three times; the heating reflux is heating to 70-90°C and reflux for 36-48 hours; The usage ratio of the crude product and the n-hexane copolymer is (1-2) mL: (50-80) mL.

[0009] Furthermore, the specific steps of hydrolyzing the polymer are: The copolymer is dissolved in DCM, and then an excess of trimethylsilyl bromide is added under a N2 atmosphere to react to obtain a reaction mixture; the reaction mixture is heated and stirred, and then an excess of methanol is added to obtain a precipitated copolymer; the precipitated copolymer is sequentially washed and dried to obtain a hydrolyzed polymer; The usage ratio of the copolymer and DCM is (30-50) mg: (2-20) mL; The usage ratio of the copolymer, trimethylsilyl bromide and methanol is (30-50) mg: (1-3) mL: (1-3) mL; The temperature when adding excess trimethylsilyl bromide is 0°C; The heating is from 0°C to room temperature; the stirring time is 12 h.

[0010] Furthermore, the preparation method of the catalyst is: 2,2'-bipyridine-6,6'-dicarboxylic acid, Ru(DMSO)4Cl2, and NEt3 were added to methanol and refluxed in a N2 atmosphere to obtain Ru(bda)(DMSO)2; After mixing 4-pyridine, Ru(bda)(DMSO)2 and methanol, degassing and refluxing in a N2 atmosphere, eluting and purifying, Ru(bda)(DMSO)(4-picoline) catalyst is obtained; The amount ratio of 2,2'-bipyridine-6,6'-dicarboxylic acid, Ru(DMSO)4Cl2, NEt3 and methanol is 488 mg:968 mg:1.6 mL:80 mL; reflux is performed in a N2 atmosphere, and the reflux time for obtaining Ru(bda)(DMSO)2 is 4 h; The usage ratio of 4-pyridine, Ru(bda)(DMSO)2 and methanol is 93 mg:500 mg:40 mL; The reflux time of the Ru(bda)(DMSO)(4-picoline) catalyst was 1 h; The eluent used for the elution is a mixture of dichloromethane and methanol in a volume ratio of 1:1.

[0011] Furthermore, the specific steps of carrying out coordination reaction between the hydrolyzed polymer and the catalyst are as follows: The hydrolyzed polymer and the catalyst are stoichiometrically combined in methanol and stirred under a N2 atmosphere for coordination reaction to obtain a polymer grafted with the catalyst; The usage ratio of the hydrolyzed polymer and the catalyst is (10-20) mg: (32-50) mg; The ratio of the polymer and solvent used in the grafting catalyst is (5-10) mg: (5-8) mL; The solvent is methanol or acetonitrile.

[0012] Furthermore, the specific steps of carrying out coordination reaction between the hydrolyzed polymer and the catalyst are as follows: The hydrolyzed polymer and the catalyst are stoichiometrically combined in methanol and stirred under a N2 atmosphere for coordination reaction to obtain a polymer grafted with the catalyst; The usage ratio of the hydrolyzed polymer and the catalyst is (10-20) mg: (32-50) mg; The ratio of the polymer and solvent used in the grafting catalyst is (5-10) mg: (5-8) mL; The solvent is methanol or acetonitrile.

[0013] The invention also discloses a photoelectric anode of a polymer electrolyte material prepared by the preparation method.

[0014] The present invention also discloses the application of the above polymer electrolyte material photoanode in photoelectrocatalysis, which comprises the following steps: A three-electrode system is constructed using the application in photoelectrocatalysis as the working electrode, and an electrocatalytic reaction is carried out in the electrolyte solution in the three-electrode system to release oxygen.

[0015] Furthermore, the electrolyte solution is a neutral solution; the concentration of the electrolyte solution is 0.5 M.

[0016] Furthermore, the neutral solution is prepared by adding 0.5 M sodium perchlorate to a phosphate buffer solution.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The invention discloses a method for preparing a photoanode of a polymer electrolyte material. By designing the structure of the polymer, a block phosphonic acid group fragment is introduced. Compared with the traditional single phosphonic acid group, the block phosphonic acid group fragment can effectively slow down the desorption process of the catalyst, effectively prolong the residence time of the catalyst on the photoanode, and improve the stability of the photoelectrocatalysis; at the same time, the hydrophobic structure of the long alkyl chain is introduced. The hydrophobic structure of the long alkyl chain allows the desorbed catalyst to approach the semiconductor interface, so that it is in a dynamic equilibrium of adsorption-desorption, further prolonging the residence time of the catalyst on the photoanode, and improving the stability of the photoelectrocatalysis; at the same time, in the preparation process, through the non-molecular interaction between the long alkyl chains, the self-assembly strategy is adopted to simplify the traditional complex synthesis process, and at the same time, by accurately controlling the composition of the catalyst and the photosensitizer, the photoelectrocatalytic performance of the photoanode of the polymer electrolyte material is further optimized. This precise composition control enables the photoanode to utilize light energy more efficiently in the photoelectrocatalytic process, improves the separation efficiency of photogenerated electrons and holes, and improves the catalytic stability.

[0018] Furthermore, the preparation method of the present invention has the advantages of controllable process, simple technology, low cost, etc., is suitable for large-scale production, and is conducive to industrial application.

[0019] The present invention also discloses a photoanode made of a polymer electrolyte material prepared by the above-mentioned preparation method. The photoanode has multiple advantages such as stable structure and good oxygen evolution effect. It not only optimizes the structure of the dye-sensitized photoanode, but also significantly improves its photoelectrocatalytic water oxidation performance, which is of great significance for promoting the development of photoelectrocatalytic technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The nuclear magnetic hydrogen spectra of the Ru(bda)(DMSO)(4-picoline) catalyst and the RuPSL photosensitizer prepared in Example 1 of the present invention; Among them: a-Ru(bda)(DMSO)(4-picoline) catalyst; b-RuPSL photosensitizer; Figure 2 This is the infrared spectrum of the copolymer prepared in Example 1 of the present invention; Figure 3The ultraviolet absorption spectrum of the photoanode of the polymer electrolyte material photoanode prepared in Example 1 of the present invention; Figure 4 This is a photoelectrocatalytic performance diagram of the polymer electrolyte material photoanode prepared in Example 1 of the present invention; Figure 5 The long-term photocurrent test diagram of the electrocatalytic performance diagram of the polymer electrolyte material photoanode prepared in Example 1 of the present invention and the amount of oxygen evolved in the photoelectrocatalytic water decomposition reaction; Among them: a-long-term photocurrent test diagram; b-oxygen evolution in the photoelectrocatalytic water decomposition reaction; Figure 6 This is a diagram of the photoelectric conversion efficiency of the polymer electrolyte material photoanode prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0022] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0023] In this article, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are for simplicity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to have included and specifically disclosed all possible secondary ranges and individual values ​​within the range (including integers and fractions).

[0024] In this document, unless otherwise specified, “includes,” “including,” “contains,” “has,” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”

[0025] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0026] The present invention provides a polymer electrolyte material photoanode. By designing a polymer, a copolymer scaffold containing a pyridine group, a phosphonic acid group and a long alkyl chain is proposed. A catalyst is then grafted onto the polymer through coordination and adsorbed on the surface of a metal oxide. Then, a photosensitizer is connected through the non-molecular interaction of the long alkyl chain. The polymer electrolyte material photoanode has the characteristics of stable structure and good photoelectrocatalytic performance, and exhibits excellent oxygen evolution effect in photoelectrocatalytic decomposition of water and oxygen evolution.

[0027] The chemical structure of the polymer designed above is shown in formula (I): ; (I) The R group is C 10 H 21 Long alkyl chains; The present invention also discloses a method for preparing the above-mentioned polymer electrolyte material photoanode, comprising the following steps: S1: monomers 2-methylprop-2-enoic acid pyridin-4-yl ester, {[(2-methyl-1-oxyylideneprop-2-enyl)oxy]methyl}phosphonic acid diethyl ester and 2-methylprop-2-enoic acid decyl ester are polymerized by free radical polymerization to obtain a copolymer; S2: hydrolyzing the copolymer obtained in step S1 under the action of trimethylsilyl bromide to obtain a hydrolyzed polymer; S3: performing coordination reaction on the hydrolyzed polymer obtained in step S2 and the catalyst (Ru(bda)(DMSO)(4-picoline)) to obtain a polymer grafted with the catalyst; S4: dissolving the obtained polymer of the grafted catalyst in methanol to obtain a mixed solution, coating an electrode of a core-shell structure on a conductive glass FTO and placing it in the mixed solution to obtain an assembled electrode with a surface-anchored catalyst; S5: The assembled electrode with the surface-anchored catalyst is placed in a photosensitizer (RuPSL) solution to obtain a polymer electrolyte material photoanode.

[0028] Preferably, in S1, the preparation of the copolymer comprises the following steps: Pyridin-4-yl 2-methylprop-2-enoate, diethyl {[(2-methyl-1-oxyylideneprop-2-enyl)oxy]methyl}phosphonate and decyl 2-methylprop-2-enoate were dissolved in anhydrous and oxygen-free THF, subjected to three freeze-pump-thaw cycles under nitrogen atmosphere, and finally O2 was removed from the solvent and heated to 70 °C and refluxed for 48 h; Stop heating, wait for the mixture to cool to room temperature, concentrate the crude product in tetrahydrofuran to 1 mL, and then add 50 mL of n-hexane to precipitate the copolymer; The solid was filtered and washed with n-hexane to remove unreacted monomers; The product was isolated and dried under high vacuum to give a white solid (copolymer).

[0029] Preferably, the hydrolysis reaction of the copolymer comprises the following steps: The copolymer was dissolved in 2 mL of dry DCM, and an excess of trimethylsilyl bromide was added at 0 °C under N2 atmosphere to obtain a reaction mixture; The reaction mixture was heated from 0 °C to room temperature and stirred overnight, and then the copolymer was precipitated after adding excess methanol; The solid was filtered and washed with methanol and the product was isolated and dried under high vacuum to give a pale yellow solid (copolymer).

[0030] Preferably, in S3, the catalyst (Ru(bda)(DMSO)(4-picoline)) is prepared by: 488 mg of 2,2'-bipyridine-6,6'-dicarboxylic acid, 968 mg of Ru(DMSO)4Cl2, and 1.6 mL of NEt3 were added to 80 mL of methanol and refluxed under N2 for 4 h to obtain Ru(bda)(DMSO)2; A mixture of 4-pyridine (93 mg) and Ru(bda)(DMSO)2 (500 mg) in methanol (40 mL) was degassed with N2 and refluxed for 1 h; The product was purified by silica gel column chromatography using dichloromethane-methanol (1:1, v:v) as eluent.

[0031] Preferably, in S3, the step of carrying out coordination reaction between the hydrolyzed polymer and the catalyst (Ru(bda)(DMSO)(4-picoline)) is: The corresponding dried hydrolyzed polymer was stoichiometrically combined with Ru(bda)(DMSO)(4-picoline) in dry methanol (10~15 mL) and stirred overnight under N2 atmosphere to obtain a coordination copolymer; part of the reaction volume was removed and added to dry methanol to a final concentration of 0.25 mM for immobilization; the immobilization solution was stored in the dark at room temperature to form a reddish-brown solution (polymer grafted with the catalyst).

[0032] Preferably, in S5, the preparation of the photosensitizer (RuPSL) comprises the following steps: A mixture of [Ru(Cl)2(py)2] (1.56 mmol) and 4,4'-heptadecanyl-2,2'-bipyridine (1.54 mmol) in a 1:1:1 mixture of ethanol:water:chloroform (60 mL) was degassed with N2 bubbling for 15 min and then heated at 110 °C for 2 days; after cooling to room temperature, an orange-red fraction was extracted and separated; the solvent was removed by air separation, and the red compound was extracted with chloroform to obtain the desired compound RuPSL.

[0033] The present invention also discloses the application of the above polymer electrolyte material photoanode in photoelectrocatalysis, which comprises the following steps: A three-electrode system is constructed using a polymer electrolyte material photoanode as the working electrode, and an electrocatalytic reaction is carried out in the electrolyte solution to release oxygen.

[0034] Preferably, the electrolyte solution is a neutral solution; the concentration of the electrolyte solution is 0.5 M.

[0035] Preferably, the neutral solution is a phosphate buffer solution with 0.5 M sodium perchlorate added.

[0036] Wherein, the chemical structural formula of the photosensitizer is: .

[0037] The chemical formula of the catalyst is: .

[0038] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only intended to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0039] The following examples use conventional instruments and equipment in the art. The experimental methods in the following examples where specific conditions are not specified are usually carried out under conventional conditions or under conditions recommended by the manufacturer. The various raw materials used in the following examples are conventional commercial products unless otherwise specified, and their specifications are conventional specifications in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" means weight percentage, "part" means weight part, and ratio means weight ratio.

[0040] Example 1 A method for preparing a photoanode of a polymer electrolyte material comprises the following steps: In this embodiment, the catalyst and the photosensitizer are self-assembled through non-molecular interactions, the molecular ratio of the photosensitizer RuPSL to the catalyst Ru-bda in the electrolyte material photoanode is 1, and the photosensitizer RuPSL and the catalyst Ru-bda used are both powder samples; The catalyst monomer synthesis part is as follows: 488 mg of 2,2'-bipyridine-6,6'-dicarboxylic acid, 968 mg of Ru(DMSO)4Cl2, and 1.6 mL of NEt3 are added to 80 mL of methanol, and N2 is refluxed for 4 h to obtain Ru(bda)(DMSO)2; a mixture of 4-pyridine (93 mg) and Ru(bda)(DMSO)2 (500 mg) in methanol (40 mL) is degassed with N2 and refluxed for 1 h, and the product is purified by silica gel column chromatography using dichloromethane-methanol (1:1, v:v) as an eluent; The copolymer synthesis part is as follows: 45 mg of 2-methylprop-2-enoic acid pyridin-4-yl ester, 34 mg of {[(2-methyl-1-oxyylideneprop-2-enyl)oxy]methyl}phosphonic acid diethyl ester and 32 mg of 2-methylprop-2-enoic acid decyl ester are dissolved in 7 mL of anhydrous and oxygen-free THF, and subjected to three freeze-pump-thaw cycles under a nitrogen atmosphere, and finally O2 is removed from the solvent, and the mixture is heated to 70°C and refluxed for 48 h; the heating is stopped, and after the mixture is cooled to room temperature, the crude product in tetrahydrofuran is concentrated to 1 mL, and then 50 mL of n-hexane is added to precipitate the copolymer, the solid is filtered and washed with n-hexane to remove unreacted monomers, the product is separated and dried under high vacuum to obtain a white solid; the unhydrolyzed polymer is dissolved in 2 mL of dry DCM, and an excess of trimethylsilyl bromide is added at 0°C and under a N2 atmosphere; the reaction mixture is heated from 0 to 40 °C and then cooled to room temperature. ℃ and heated to room temperature and stirred overnight, then the copolymer was precipitated after adding excess methanol; the solid was filtered and washed with methanol, the product was isolated and dried under high vacuum to obtain a light yellow solid; The coordination reaction of the hydrolyzed polymer and the catalyst was carried out as follows: 10 mg of the corresponding dry hydrolyzed polymer was stoichiometrically combined with 32 mg of Ru(bda)(DMSO)(4-picoline) in 8 mL of dry methanol and stirred overnight under N2 atmosphere to obtain a coordination copolymer, and a portion of the reaction volume was removed and added to dry methanol to a final concentration of 0.25 mM for immobilization, and the immobilization solution was stored in the dark at room temperature to form a reddish-brown solution; The synthesis part of the photosensitizer is as follows: a mixture of [Ru(Cl)2(py)2] (1.56 mmol) and 4,4'-heptadecanyl-2,2'-bipyridine (1.54 mmol) in a 1:1:1 mixture of ethanol: water: chloroform (60 mL) is degassed by bubbling with N2 for 15 minutes, then heated at 110°C for 2 days, cooled to room temperature, extracted and separated an orange-red fraction, the solvent is removed by air separation, and the red compound is extracted with chloroform to obtain the desired compound RuPSL; the photosensitizer solution is obtained by mixing the photosensitizer and methanol, and the concentration is 5 mg / mL; 5 mg of the polymer grafted with the catalyst was dissolved in 5 mL of methanol to obtain a mixed solution; an electrode with a core-shell structure was coated on a substrate and then immersed in the mixed solution to obtain an assembled electrode FTO|SnO2 / TiO2|-polymer-Rubda with a surface-anchored catalyst (electrode 2); the assembled electrode with a surface-anchored catalyst was placed in a photosensitizer solution to obtain a polymer electrolyte material photoanode FTO|SnO2 / TiO2|-polymer-Rubda-PuPSL (electrode 1).

[0041] The polymer electrolyte material photoanode prepared in Example 1 was used as the working electrode, the platinum wire was used as the counter electrode, and the saturated silver chloride electrode was used as the reference electrode to construct a three-electrode system, and a photoelectrocatalytic reaction was carried out in 1 M phosphate buffer solution (electrolyte solution, pH 7).

[0042] Example 2 A method for preparing a photoanode of a polymer electrolyte material comprises the following steps: The catalyst monomer synthesis part is as follows: 488 mg of 2,2'-bipyridine-6,6'-dicarboxylic acid, 968 mg of Ru(DMSO)4Cl2, and 1.6 mL of NEt3 are added to 80 mL of methanol, and N2 is refluxed for 4 h to obtain Ru(bda)(DMSO)2; a mixture of 4-pyridine (93 mg) and Ru(bda)(DMSO)2 (500 mg) in methanol (40 mL) is degassed with N2 and refluxed for 1 h, and the product is purified by silica gel column chromatography using dichloromethane-methanol (1:1, v:v) as an eluent; The copolymer synthesis part is as follows: 50 mg of 2-methylprop-2-enoic acid pyridin-4-yl ester, 30 mg of {[(2-methyl-1-oxyylideneprop-2-enyl)oxy]methyl}phosphonic acid diethyl ester and 40 mg of 2-methylprop-2-enoic acid decyl ester are dissolved in 15 mL of anhydrous and oxygen-free THF, and subjected to three freeze-pump-thaw cycles under a nitrogen atmosphere, and finally O2 is removed from the solvent, and the mixture is heated to 90°C and refluxed for 36 h; the heating is stopped, and after the mixture is cooled to room temperature, the crude product in tetrahydrofuran is concentrated to 2 mL, and then 80 mL of n-hexane is added to precipitate the copolymer, the solid is filtered and washed with n-hexane to remove unreacted monomers, the product is separated and dried under high vacuum to obtain a white solid; the unhydrolyzed polymer is dissolved in 20 mL of dry DCM, and an excess of trimethylsilyl bromide is added at 0°C and under a N2 atmosphere; the reaction mixture is heated from 0 to 40 °C and then cooled to room temperature. ℃ and heated to room temperature and stirred overnight, then the copolymer was precipitated after adding excess methanol; the solid was filtered and washed with methanol, the product was isolated and dried under high vacuum to obtain a light yellow solid (polymer after hydrolysis); The coordination reaction of the hydrolyzed polymer and the catalyst was carried out as follows: 20 mg of the corresponding dry hydrolyzed polymer was stoichiometrically combined with 50 mg of Ru(bda)(DMSO)(4-picoline) in 5 mL of dry methanol and stirred overnight under N2 atmosphere to obtain a coordination copolymer, and a part of the reaction volume was removed and added to dry methanol to a final concentration of 0.25 mM for immobilization, and the immobilization solution was stored in the dark at room temperature to form a reddish-brown solution; The synthesis part of the photosensitizer is as follows: a mixture of [Ru(Cl)2(py)2] (1.56 mmol) and 4,4'-heptadecanyl-2,2'-bipyridine (1.54 mmol) in a 1:1:1 mixture of ethanol: water: chloroform (60 mL) is degassed by bubbling with N2 for 15 minutes, then heated at 120°C for 3 days, cooled to room temperature, extracted and separated an orange-red fraction, the solvent is removed by air separation, and the red compound is extracted with chloroform to obtain the desired compound RuPSL; the photosensitizer solution is obtained by mixing the photosensitizer and methanol, and the concentration is 8 mg / mL; 5 mg of the polymer grafted with the catalyst was dissolved in 5 mL of methanol to obtain a mixed solution; an electrode with a core-shell structure was coated on a substrate and then immersed in the mixed solution to obtain an assembled electrode with a surface-anchored catalyst; the assembled electrode with a surface-anchored catalyst was placed in a photosensitizer solution to obtain a polymer electrolyte material photoanode.

[0043] Example 3 A method for preparing a photoanode of a polymer electrolyte material comprises the following steps: The catalyst monomer synthesis part is as follows: 488 mg of 2,2'-bipyridine-6,6'-dicarboxylic acid, 968 mg of Ru(DMSO)4Cl2, and 1.6 mL of NEt3 are added to 80 mL of methanol, and N2 is refluxed for 4 h to obtain Ru(bda)(DMSO)2; a mixture of 4-pyridine (93 mg) and Ru(bda)(DMSO)2 (500 mg) in methanol (40 mL) is degassed with N2 and refluxed for 1 h, and the product is purified by silica gel column chromatography using dichloromethane-methanol (1:1, v:v) as an eluent; The copolymer synthesis part is as follows: 40 mg of 2-methylprop-2-enoic acid pyridin-4-yl ester, 10 mg of {[(2-methyl-1-oxyylideneprop-2-enyl)oxy]methyl}phosphonic acid diethyl ester and 30 mg of 2-methylprop-2-enoic acid decyl ester are dissolved in 10 mL of anhydrous and oxygen-free THF, and subjected to three freeze-pump-thaw cycles under a nitrogen atmosphere, and finally O2 is removed from the solvent, and the mixture is heated to 90°C and refluxed for 36 h; the heating is stopped, and after the mixture is cooled to room temperature, the crude product in tetrahydrofuran is concentrated to 2 mL, and then 80 mL of n-hexane is added to precipitate the copolymer, the solid is filtered and washed with n-hexane to remove unreacted monomers, and the product is separated and dried under high vacuum to obtain a white solid; the unhydrolyzed polymer is dissolved in 20 mL of dry DCM, and an excess of trimethylsilyl bromide is added at 0°C and under a N2 atmosphere; the reaction mixture is heated from 0 to 40°C, and then heated to 40°C. ℃ and heated to room temperature and stirred overnight, then the copolymer was precipitated after adding excess methanol; the solid was filtered and washed with methanol, the product was isolated and dried under high vacuum to obtain a light yellow solid (polymer after hydrolysis); The coordination reaction of the hydrolyzed polymer and the catalyst was carried out as follows: 20 mg of the corresponding dry hydrolyzed polymer was stoichiometrically combined with 50 mg of Ru(bda)(DMSO)(4-picoline) in 7 mL of dry acetonitrile and stirred overnight under N2 atmosphere to obtain a coordination copolymer, and a part of the reaction volume was removed and added to dry methanol to a final concentration of 0.25 mM for immobilization, and the immobilization solution was stored in the dark at room temperature to form a reddish-brown solution; The synthesis part of the photosensitizer is as follows: a mixture of [Ru(Cl)2(py)2] (1.56 mmol) and 4,4'-heptadecanyl-2,2'-bipyridine (1.54 mmol) in a 1:1:1 mixture of ethanol: water: chloroform (60 mL) is degassed by bubbling with N2 for 15 minutes, then heated at 120°C for 3 days, cooled to room temperature, extracted and separated an orange-red fraction, the solvent is removed by air separation, and the red compound is extracted with chloroform to obtain the desired compound RuPSL; the photosensitizer solution is obtained by mixing the photosensitizer and methanol, and the concentration is 8 mg / mL; 5 mg of the polymer grafted with the catalyst was dissolved in 5 mL of methanol to obtain a mixed solution; an electrode with a core-shell structure was coated on a substrate and then immersed in the mixed solution to obtain an assembled electrode with a surface-anchored catalyst; the assembled electrode with a surface-anchored catalyst was placed in a photosensitizer solution to obtain a polymer electrolyte material photoanode.

[0044] Comparative Example The pretreated FTO|TiO2 was used as the control group, and photoelectrocatalysis was carried out under the same conditions.

[0045] The potentials of all the above electrodes were calibrated to the reversible hydrogen electrode (RHE).

[0046] Figure 1 The NMR hydrogen spectra of the Ru(bda)(DMSO)(4-picoline) catalyst and the RuPSL photosensitizer prepared in Example 1 of the present invention, wherein a is Ru(bda)(DMSO)(4-picoline), 1 H NMR (400MHz, CD3OD): δ 8.5 (m, 2H), 8.1 (t, 4H), 7.7 (d, 2H), 7.1 (d, 2H), 2.9 (s, 6H), 2.3 (s, 3H)., b is RuPSL, 1 H NMR (400 MHz,CD3OD): δ 8.71-8.69 (d, 4H), 8.62 (d,2H), 8.14-8.10 (t,4H), 7.82-7.81 (m, 4H), 7.64-7.62 (d, 2H), 7.51-7.46 (t, 4H), 7.35-7.34 (dd,2H), 2.87-2.83 (t, 4H), 1.77-1.70 (q, 4H), 1.40-1.25 (m, 56H), 0.91-0.88 (t,6H). It can be seen that Ru(bda)(DMSO)(4-picoline) was successfully synthesized.

[0047] Figure 2 This is the infrared spectrum of the copolymer prepared in Example 1 of the present invention. It can be seen that the polymer scaffold is successfully synthesized. The skeleton stretching vibration band of the pyridine ring is 1600 cm -1 The infrared characteristic absorption peak of PO bond is 1150 cm -1 .

[0048] Figure 3The ultraviolet absorption spectrum of the photoanode of the polymer electrolyte material prepared in Example 1 of the present invention shows that when the assembled electrode with the surface-anchored catalyst is placed in a methanol solution of the photosensitizer, the absorbance of the photosensitizer / catalyst assembled electrode at 450 nm increases, proving that the photosensitizer / catalyst assembled electrode is successfully prepared by self-assembly.

[0049] Figure 4 The photoelectrocatalytic performance diagram of the polymer electrolyte material photoanode prepared in Example 1 of the present invention shows that the SnO2 / TiO2 core / shell structure has a better local charge separation effect, which is because the conduction band potential difference between the oxides produces an energy barrier; after 90 s of illumination, the photocurrent density of the FTO|SnO2 / TiO2|-polymer-Rubda-PuPSL (electrode 1) component is 0.28 mA / cm 2 .

[0050] Figure 5 The long-term photocurrent test diagram of the electrocatalytic performance diagram of the polymer electrolyte material photoanode prepared in Example 1 of the present invention and the amount of oxygen evolved in the photoelectrocatalytic water decomposition reaction show that after continuous illumination for 3000 s, the photocurrent density of FTO|SnO2 / TiO2|-polymer-Rubda-PuPSL is 0.1 mA / cm 2 , the current holding rate was 33%, and 0.14 μmol of O2 was produced.

[0051] Figure 6 This is a diagram of the photoelectric conversion efficiency of the polymer electrolyte material photoanode prepared in Example 1 of the present invention. It can be seen that the efficiency of FTO|SnO2 / TiO2|-polymer-Rubda-PuPSL in generating photocurrent at a wavelength of 450 nm reaches 13.7%, which is one of the high values ​​of organic photosensitizers in DSPECs water oxidation.

[0052] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a photoanode of a polymer electrolyte material, characterized in that: The following steps are involved: The copolymer is subjected to a hydrolysis reaction to obtain a hydrolyzed polymer; the hydrolyzed polymer is subjected to a coordination reaction with a catalyst to obtain a polymer grafted with the catalyst; The polymer grafted with the catalyst is dissolved in a solvent to obtain a mixed solution; The core-shell structure electrode is coated on the substrate and then immersed in the mixed solution to obtain an assembled electrode with the catalyst anchored on the surface; The assembled electrode with the catalyst anchored on the surface is placed in a photosensitizer solution to obtain a polymer electrolyte material photoanode.

2. The method for preparing a photoanode made of a polymer electrolyte material according to claim 1, characterized in that: The chemical structural formula of the hydrolyzed polymer is as follows: ； Where: R is C 10 H 21 Long alkyl chains.

3. The method for preparing a photoanode made of a polymer electrolyte material according to claim 1, characterized in that: The preparation method of the copolymer is: Pyridin-4-yl 2-methylprop-2-enoate, diethyl {[(2-methyl-1-oxyylideneprop-2-enyl)oxy]methyl}phosphonate and decyl 2-methylprop-2-enoate were dissolved in THF, subjected to freeze-pump-thaw cycles under a nitrogen atmosphere, and then heated to reflux to obtain a mixture; The mixture is cooled and concentrated to obtain a crude product; n-hexane copolymer is added to the crude product for reaction to obtain a copolymer; The usage ratio of the 2-methylprop-2-enoic acid pyridin-4-yl ester, {[(2-methyl-1-oxyylideneprop-2-enyl)oxy]methyl}phosphonic acid diethyl ester, 2-methylprop-2-enoic acid decyl ester and THF is (40-50) mg: (10-30) mg: (30-40) mg: (7-15) mL; The number of freeze-pump-thaw cycles is three times; the heating reflux is heating to 70-90°C and reflux for 36-48h; The usage ratio of the crude product and the n-hexane copolymer is (1-2) mL: (50-80) mL.

4. The method for preparing a photoanode made of a polymer electrolyte material according to claim 1, characterized in that: The specific steps of hydrolyzing the polymer are as follows: The copolymer is dissolved in DCM, and then an excess of trimethylsilyl bromide is added under a N2 atmosphere to react to obtain a reaction mixture; the reaction mixture is heated and stirred, and then an excess of methanol is added to obtain a precipitated copolymer; the precipitated copolymer is sequentially washed and dried to obtain a hydrolyzed polymer; The usage ratio of the copolymer and DCM is (30-50) mg: (2-20) mL; The usage ratio of the copolymer, trimethylsilyl bromide and methanol is (30-50) mg: (1-3) mL: (1-3) mL; The temperature when adding excess trimethylsilyl bromide is 0°C; The heating is from 0°C to room temperature; the stirring time is 12 h.

5. The method for preparing a photoanode made of a polymer electrolyte material according to claim 1, characterized in that: The preparation method of the catalyst is: 2,2'-bipyridine-6,6'-dicarboxylic acid, Ru(DMSO)4Cl2, and NEt3 were added to methanol and refluxed in a N2 atmosphere to obtain Ru(bda)(DMSO)2; After mixing 4-pyridine, Ru(bda)(DMSO)2 and methanol, degassing and refluxing in a N2 atmosphere, eluting and purifying, Ru(bda)(DMSO)(4-picoline) catalyst is obtained; The amount ratio of 2,2'-bipyridine-6,6'-dicarboxylic acid, Ru(DMSO)4Cl2, NEt3 and methanol is 488 mg:968 mg:1.6 mL:80 mL; reflux is performed in a N2 atmosphere, and the reflux time of Ru(bda)(DMSO)2 is 4 h; The usage ratio of 4-pyridine, Ru(bda)(DMSO)2 and methanol is 93 mg:500 mg:40 mL; The reflux time of the Ru(bda)(DMSO)(4-picoline) catalyst was 1 h; The eluent used for the elution is a mixture of dichloromethane and methanol in a volume ratio of 1:

1.

6. The method for preparing a photoanode made of a polymer electrolyte material according to claim 1, characterized in that: The specific steps of the coordination reaction between the hydrolyzed polymer and the catalyst are as follows: The hydrolyzed polymer and the catalyst are stoichiometrically combined in methanol and stirred under a N2 atmosphere for coordination reaction to obtain a polymer grafted with the catalyst; The ratio of the hydrolyzed polymer to the catalyst is (10-20) mg: (32-50) mg; The ratio of the polymer and solvent used in the grafting catalyst is (5-10) mg: (5-8) mL; The solvent is methanol or acetonitrile.

7. The method for preparing a polymer electrolyte material photoanode according to claim 1, characterized in that: The photosensitizer solution is obtained by mixing a photosensitizer and methanol; the concentration of the photosensitizer solution is 5-8 mg / mL; The preparation method of the photosensitizer is: [Ru(Cl)2(py)2] and 4,4'-heptadecanyl-2,2'-bipyridine are dissolved in a mixed solvent, and then degassed by bubbling with N2, and then heated to obtain a product; the product is extracted and desolvated to obtain a photosensitizer; The amount ratio of [Ru(Cl)2(py)2], 4,4'-heptadecanyl-2,2'-bipyridine and the mixed solvent is 1.56 mmol:1.54 mmol:60 mL; The mixed solvent is a mixture of ethanol, water and chloroform in a volume ratio of 1:1:1; The heating temperature is 110-120° C. and the heating time is 2-3 days.

8. A polymer electrolyte material photoanode, characterized in that: The method is prepared by any one of claims 1 to 6.

9. Use of a polymer electrolyte material photoanode according to claim 8 in photoelectrocatalysis, characterized in that: The following steps are involved: A three-electrode system is constructed using the application in photoelectrocatalysis as the working electrode, and an electrocatalytic reaction is carried out in the electrolyte solution in the three-electrode system to release oxygen.

10. The use of a polymer electrolyte material photoanode in photoelectrocatalysis according to claim 9, characterized in that: The electrolyte solution is a neutral solution; the concentration of the electrolyte solution is 0.5 M; The neutral solution is prepared by adding 0.5 M sodium perchlorate to a phosphate buffer solution.

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