Highly efficient and recyclable catalyst for photocatalytic reaction and preparation method and application thereof

Abstract

The present invention relates to the technical field of catalysts, and discloses a highly efficient recyclable catalyst for photocatalytic reactions, its preparation method and application. The highly efficient recyclable catalyst is a silica microsphere loaded with a photosensitizer and a transition metal copolymer molecule. The preparation method is as follows: ammonia water and absolute ethanol are mixed evenly, and tetraethyl orthosilicate is added to obtain a silica microsphere suspension; 3-aminopropyltriethoxysilane is added to the silica microsphere suspension, and the product 1 is obtained by centrifugation; NHS-CPP is dissolved in DMF, and the product 1 is added for reaction to obtain the product 2; the complex monomer and the photosensitizer monomer are mixed with the product 2 and dissolved in tetrahydrofuran, and an initiator is added for reaction to obtain a precipitate; the precipitate is dissolved in tetrahydrofuran, and NiCl2.DME is added for reaction to obtain the product. The highly efficient recyclable catalyst of the present invention belongs to homogeneous catalysis. The photosensitizer and the transition metal copolymer molecule produce a synergistic catalytic effect, with high catalytic efficiency, and the catalyst is easy to separate from the product and can be recycled and reused.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and in particular to a highly efficient and recyclable catalyst for photocatalytic reaction, and a preparation method and application thereof. Background Art

[0002] Photocatalysis is a way of using light energy to transform substances. It is a chemical reaction of substances under the combined action of light and catalysts. Photocatalytic reaction is a process in which a reaction system containing a catalyst excites reaction molecules or excites the catalyst to form a complex with reaction molecules under light irradiation, converts light energy into chemical energy, and promotes the reaction.

[0003] At present, complex-loaded photocatalysts and small molecule photocatalysts with MOFs, COFs or molecular sieves as carriers are widely used in photocatalytic reactions. Most complex-loaded photoreaction catalysts with MOFs, COFs or molecular sieves as carriers are heterogeneous catalysis in photocatalytic reactions, resulting in poor diffusion of substrates and products in and out of heterogeneous catalysts, which cannot fully contact the substrate and have low catalytic efficiency; a few photocatalysts that can be homogeneous catalyzed cannot increase the local concentration of the catalyst, which affects the catalytic efficiency, and the homogeneous catalyst is difficult to separate from the reaction system and difficult to reuse. The catalyst cost is high, which limits its application in production or experiments. Small molecule photocatalysts are relatively dispersed in the reaction solution. When more than two catalysts are loaded on the carrier, the relative positions of the two catalysts will be unstable, resulting in low catalytic efficiency.

[0004] There is an urgent need to develop a catalyst with high catalytic efficiency and recyclability. Summary of the invention

[0005] In view of the problems existing in the prior art, the purpose of the present invention is to provide a highly efficient and recyclable catalyst for photocatalytic reactions, and a preparation method and application thereof. By loading photosensitizer and transition metal copolymer molecules with SiO2, homogeneous catalysis can be achieved, and a confinement effect on substrates and products can be produced to improve the catalytic efficiency. The catalyst is easily separated from the reaction system and can be recycled and reused.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions to achieve it.

[0007] A highly efficient and recyclable catalyst for photocatalytic reaction, the structural formula of which is as follows:

[0008]

[0009] Wherein, R1 is an alkyl group containing 1 to 4 carbon atoms; R2 is an aryl group; 0.6<x / y<1.5.

[0010] Preferably, R1 is methyl, ethyl, isopropyl or tert-butyl; R2 is phenyl, naphthyl, 4-cyanophenyl or 4-methoxyphenyl.

[0011] A method for preparing a highly efficient and recyclable catalyst for photocatalytic reaction comprises the following steps:

[0012] S1, ammonia water and anhydrous ethanol are mixed evenly in a volume ratio of 1: (20-30), heated to 30°C for insulation, and then tetraethyl silicate is added to react at 50°C for 6-10h to obtain a silica microsphere suspension;

[0013] The ratio of tetraethyl silicate to ammonia water is 1-2 mmol tetraethyl silicate / 1 ml ammonia water;

[0014] S2, adding 3-aminopropyltriethoxysilane to the silica microsphere suspension, stirring and refluxing, and then collecting the precipitate by centrifugation to obtain product 1;

[0015] The ratio of 3-aminopropyltriethoxysilane to ammonia water in step S1 is 2-3 mmol 3-aminopropyltriethoxysilane / 1 ml ammonia water;

[0016] The reaction formula for preparing product 1 is:

[0017]

[0018] S3, dissolving NHS-CPP in DMF, stirring evenly, adding product 1, reacting for 8 hours, and collecting the precipitate by centrifugation to obtain product 2;

[0019] The reaction formula for preparing product 2 is:

[0020]

[0021] S4, the complex monomer, photosensitizer monomer and product 2 are mixed and dissolved in tetrahydrofuran, an initiator is added, the mixture is reacted at 60-80° C. in a nitrogen atmosphere for 8-12 hours, and a precipitate is obtained by centrifugation to obtain an intermediate product;

[0022] S5, dissolving the intermediate product in tetrahydrofuran, adding nickel (II) chloride ethylene glycol dimethyl ether complex, reacting for 4-6 hours, and then collecting the precipitate by centrifugation to obtain; the prepared high-efficiency recyclable catalyst is recorded as P1.

[0023] Preferably, the complex monomer is denoted as m1, and the complex monomer structural formula is:

[0024]

[0025] R1 is methyl, ethyl, isopropyl or tert-butyl;

[0026] The photosensitizer monomer is recorded as m2, and the photosensitizer monomer structural formula is:

[0027]

[0028] R2 is phenyl, naphthyl, 4-cyanophenyl or 4-methoxyphenyl.

[0029] The reaction formula for preparing the highly efficient and recyclable catalyst P1 is:

[0030]

[0031] Preferably, the molar ratio of NHS-CPP to product 1 is 1:(1-1.5).

[0032] In the present invention, NHS-CPP is an abbreviation for succinimidyl-1-yl-4-cyano-4-propylthiocarbonylthiothiopentanoate.

[0033] Preferably, the molar ratio of product 2, complex monomer and photosensitizer monomer is 1:(40-60):(40:60).

[0034] Preferably, the molar ratio of nickel (II) chloride ethylene glycol dimethyl ether complex to product 2 is (40-60):1.

[0035] Preferably, the initiator is azobisisobutyronitrile, and the molar ratio of azobisisobutyronitrile to product 2 is 0.5:1.

[0036] The recovery method of the highly efficient and recyclable catalyst is:

[0037] After the catalytic reaction is completed, methanol is added to the reaction system to quench the reaction and precipitate the highly efficient and recyclable catalyst in the reaction system, which is then recovered by centrifugal separation.

[0038] Application of the above-mentioned highly efficient and recyclable catalyst in photocatalytic reactions.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The high-efficiency and recyclable catalyst of the present invention is a SiO2-loaded photosensitizer and a transition metal copolymer molecule. It belongs to homogeneous catalysis in the catalytic reaction process. The photosensitizer and the transition metal copolymer molecules produce a synergistic catalytic effect, generate more catalytic sites, the substrate contacts the catalytic sites, and the substrate and the product are easy to diffuse. The aggregation of the copolymer molecules causes it to have a confinement effect on the substrate, thereby improving the reaction catalytic activity, greatly shortening the reaction catalytic time, and improving the catalytic effect. The catalyst is easy to separate from the product and can be recycled and reused. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] Figure 1 is a transmission electron micrograph of the highly efficient and recyclable catalyst P1;

[0043] Figure 2 is a transmission electron micrograph of product 1;

[0044] Figure 3 is a transmission electron micrograph of product 2;

[0045] Figure 4 This is the NMR spectrum of the CS bond catalyzed by the highly efficient and recyclable catalyst P1;

[0046] Figure 5 This is the NMR spectrum of the CS bond catalyzed by the highly efficient and recyclable catalyst P1;

[0047] Figure 6 This is the NMR spectrum of the highly efficient and recyclable catalyst P1 catalyzing the CN bond;

[0048] Figure 7 This is the NMR spectrum of the CC bond catalyzed by the highly efficient and recyclable catalyst P1;

[0049] Figure 8 This is the NMR spectrum of CO bond catalyzed by the highly efficient and recyclable catalyst P1.

[0050] Fig. 9 This is a diagram of the catalytic yield of the highly efficient and recyclable catalyst P1 after multiple cycles of use. DETAILED DESCRIPTION

[0051] The embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention.

[0052] The present invention provides a highly efficient and recyclable catalyst, the structural formula of which is as follows:

[0053]

[0054] Wherein, R1 is an alkyl group containing 1 to 4 carbon atoms, preferably methyl, ethyl, isopropyl or tert-butyl;

[0055] R2 is aryl, phenyl, naphthyl, 4-cyanophenyl or 4-methoxyphenyl.

[0056] 0.6<x / y<1.5, preferably x / y=1.

[0057] like Figure 1The transmission electron micrograph of the highly efficient and recyclable catalyst is shown in FIG. The highly efficient and recyclable catalyst of the present invention is a silica microsphere loaded with a photosensitizer and a transition metal copolymer molecule, having a chain structure, which can be a random coil, an entangled assembly, or a hierarchical assembly due to microscopic phase separation in the solution.

[0058] The chain structure enables the high-efficiency recyclable catalyst to be well dispersed in the solution, producing more catalytic sites and fully contacting the substrate; the photosensitizer monomer and transition metal copolymer molecules of the high-efficiency recyclable catalyst are loaded on the same main chain, and the relative positions of the photosensitizer monomer and the transition metal copolymer molecules are fixed, making it easier for the coordinated transition metal copolymer molecules to capture the free radicals generated by the photosensitizer, producing a synergistic catalytic effect, improving the catalytic activity, and shortening the reaction catalytic time; and the transition metal copolymer molecules can produce a confinement effect on the substrate, increasing the local concentration of the catalyst, thereby improving the catalytic efficiency.

[0059] In the embodiments of the present invention, NHS-CPP is succinimidyl-1-yl-4-cyano-4-propylthiocarbonylthiothiopentanoate; NiCl2.DME is nickel (II) chloride ethylene glycol dimethyl ether complex; and DMF is N,N-dimethylformamide.

[0060] The present invention provides a method for preparing a highly efficient and recyclable catalyst, comprising the following steps:

[0061] S1, ammonia water and anhydrous ethanol are mixed evenly in a volume ratio of 1: (20-30), heated to 30°C for insulation, and then tetraethyl silicate is added to react at 50°C for 6-10h to obtain a silica microsphere suspension;

[0062] The ammonia water is industrial ammonia water, analytical grade ammonia water or electronic grade ammonia water, and the concentration is greater than 25%; the dosage ratio of tetraethyl silicate to ammonia water is 1-2 mmol tetraethyl silicate / 1 ml ammonia water;

[0063] S2, adding 3-aminopropyltriethoxysilane to the silica microsphere suspension, stirring and refluxing, and then collecting the precipitate by centrifugation to obtain product 1;

[0064] The ratio of 3-aminopropyltriethoxysilane to ammonia water in step S1 is 2-3 mmol 3-aminopropyltriethoxysilane / 1 ml ammonia water.

[0065] The structural formula of product 1 is:

[0066]

[0067] S3, dissolving NHS-CPP in DMF, stirring evenly, adding product 1, reacting for 8 hours, and collecting the precipitate by centrifugation to obtain product 2;

[0068] The molar ratio of NHS-CPP to product 1 is 1:(1-1.5), preferably 1:1.25. Product 2 is separated from the liquid by centrifugation.

[0069] The structural formula of product 2 is:

[0070]

[0071] S4, the complex monomer, photosensitizer monomer and product 2 are mixed and dissolved in tetrahydrofuran, an initiator is added, the mixture is reacted at 60-80° C. in a nitrogen atmosphere for 8-12 hours, and the precipitate is collected by centrifugation to obtain an intermediate product;

[0072] The molar ratio of the product 2, the complex monomer and the photosensitizer monomer is 1:(40-60):(40:60), and the preferred molar ratio of the product 2, the complex monomer and the photosensitizer monomer is 1:50:50.

[0073] The initiator is azobisisobutyronitrile, and the molar ratio of azobisisobutyronitrile to product 2 is 0.5:1.

[0074] S5, dissolving the intermediate product in tetrahydrofuran, adding nickel (II) chloride ethylene glycol dimethyl ether complex, reacting for 4-6 hours, and then collecting the precipitate by centrifugation to obtain the highly efficient and recyclable catalyst, which is denoted as P1.

[0075] The molar ratio of nickel(II) chloride ethylene glycol dimethyl ether complex to product 2 is (40-60):1, and preferably the molar ratio of nickel(II) chloride ethylene glycol dimethyl ether complex to product 2 is 50:1. In addition to nickel(II) chloride ethylene glycol dimethyl ether complex, other metal complexes can also be used.

[0076] In the present invention, the complex monomer is recorded as m1, and the complex monomer structural formula is:

[0077]

[0078] R1 is methyl, ethyl, isopropyl or tert-butyl.

[0079] The photosensitizer monomer is recorded as m2, and the photosensitizer monomer structural formula is:

[0080]

[0081] R2 is phenyl, naphthyl, 4-cyanophenyl or 4-methoxyphenyl.

[0082] The high-efficiency recyclable catalyst of the present invention uses silicon dioxide particles as a carrier, and tetraethyl orthosilicate is controllably hydrolyzed under the catalysis of ammonia water to generate silicon dioxide microspheres, and amine groups are connected to the surface of the microspheres through 3-aminopropyltriethoxysilane KH-550. The amine groups are condensed with succinimide activated ester, and a reversible addition-fragmentation chain transfer polymerization (RAFT) initiator is connected to the surface of the microspheres, and a polymer catalyst with controllable polymerization length and block length is grafted on the surface of the silicon dioxide microspheres. The size of the high-efficiency recyclable catalyst is nanometer-level, and good dispersion can be achieved in the solution. After the reaction is completed, the catalyst can be recovered by centrifugation.

[0083] The polymers involved in the present invention, such as complex monomers or photosensitizer monomers, are easy to synthesize and have controllable structures. Through free radical copolymerization of azobisisobutyronitrile (AIBN), monomers with different structures can be polymerized simultaneously to achieve control over the polymer topological structure, sequence and crosslinking degree; the initiating unit can be grafted onto other carriers to prepare composite polymer hybrid materials; different types of metal complexes can be made into monomers and copolymerized to generate polymer-loaded synergistic catalysts.

[0084] Example 1

[0085] S1, add 100 ml of anhydrous ethanol and 5 ml of ammonia water into a two-necked flask, heat to 30°C and keep warm for 3 h, add 5 mmol of tetraethyl silicate and react at 50°C for 6 h to obtain a silica microsphere suspension;

[0086] S2, 10 mmol of 3-aminopropyltriethoxysilane was added to the silica microsphere suspension, and the mixture was stirred for 4 h, then refluxed for 5 h, and centrifuged to obtain product 1; the transmission electron micrograph of product 1 is shown in FIG. Figure 2 As shown;

[0087] S3, add 2mmol NHS-CPP and 100ml DMF to the double-open bottle, stir evenly, then add 2.5mmol product 1, react at room temperature for 8h and centrifuge to obtain product 2; the transmission electron micrograph of product 2 is shown in Figure 3 As shown;

[0088] S4, add 5 mmol of complex monomer, 5 mmol of photosensitizer monomer, 0.1 mmol of product 2, and 0.05 mmol of azobisisobutyronitrile into a polymerization reaction bottle, add 5 ml of tetrahydrofuran, react at 80° C. in a nitrogen atmosphere for 12 h, and centrifuge to obtain an intermediate product;

[0089] The monomers of the complex are:

[0090]

[0091] Photosensitizer monomer is:

[0092]

[0093] S5, dissolving the intermediate product obtained in step 4 in 5 ml of tetrahydrofuran, adding 5 mmol of nickel (II) chloride ethylene glycol dimethyl ether complex, reacting for 4 hours and centrifuging to obtain the catalyst. The transmission electron micrograph of the prepared high-efficiency recyclable catalyst is shown in FIG. Figure 1 shown.

[0094] The structural formula of the highly efficient and recyclable catalyst of Example 1 is:

[0095]

[0096] Example 2

[0097] S1, add 150 ml of anhydrous ethanol and 5 ml of ammonia water into a two-necked flask, heat to 30°C and keep warm for 3 h, add 10 mmol of tetraethyl silicate and react at 50°C for 10 h to obtain a silica microsphere suspension;

[0098] S2, 15 mmol of 3-aminopropyltriethoxysilane was added to the silica microsphere suspension, and the mixture was stirred for 4 h, then refluxed for 5 h, and centrifuged to obtain product 1; the transmission electron micrograph of product 1 is shown in FIG. Figure 2 As shown;

[0099] S3, add 2 mmol of NHS-CPP and 100 ml of DMF to a double-open bottle, stir evenly, then add 3 mmol of product 1, react at room temperature for 8 h, and then centrifuge to obtain product 2;

[0100] S4, add 6mmol of complex monomer, 4mmol of photosensitizer monomer, 0.1mmol of product 2, and 0.05mmol of azobisisobutyronitrile into a polymerization reaction bottle, add 5ml of tetrahydrofuran, react at 80°C in a nitrogen atmosphere for 12h, and centrifuge to obtain an intermediate product;

[0101] Wherein, R1 of the complex monomer is ethyl, and R2 of the photosensitizer monomer is naphthyl;

[0102] S5, dissolving the intermediate product obtained in step 4 in 5 ml of tetrahydrofuran, adding 6 mmol of nickel (II) chloride ethylene glycol dimethyl ether complex, reacting for 4 hours, and then centrifuging to obtain the product.

[0103] Example 3

[0104] S1, add 125 ml of anhydrous ethanol and 5 ml of ammonia water into a two-necked flask, heat to 30°C and keep warm for 3 h, add 6 mmol of tetraethyl silicate and react at 50°C for 8 h to obtain a silica microsphere suspension;

[0105] S2, adding 12.5 mmol of 3-aminopropyltriethoxysilane to the silica microsphere suspension, stirring for 4 h, then refluxing for 5 h, and centrifuging to obtain product 1;

[0106] S3, add 2 mmol of NHS-CPP and 100 ml of DMF to a double-open bottle, stir evenly, then add 2 mmol of product 1, react at room temperature for 8 h, and then centrifuge to obtain product 2;

[0107] S4, add 4 mmol of complex monomer, 6 mmol of photosensitizer monomer, 0.1 mmol of product 2, and 0.05 mmol of azobisisobutyronitrile into a polymerization reaction bottle, add 5 ml of tetrahydrofuran, react at 60° C. in a nitrogen atmosphere for 12 h, and centrifuge to obtain an intermediate product;

[0108] Wherein, R1 of the complex monomer is isopropyl, and R2 of the photosensitizer monomer is phenyl.

[0109] S5, dissolving the intermediate product obtained in step 4 in 5 ml of tetrahydrofuran, adding 4 mmol of nickel (II) chloride ethylene glycol dimethyl ether complex, reacting for 5 hours, and then centrifuging to obtain the product.

[0110] The high-efficiency recyclable catalyst of the present invention can be used in photocatalytic reactions to improve the reaction rate and yield of the photocatalytic reactions.

[0111] The highly efficient and recyclable catalyst P1 prepared in Example 1 was used to catalyze different types of photocatalytic reactions. The principle of photocatalysis is as follows:

[0112] Highly efficient and recyclable catalyst P1 photocatalyzes the coupling reaction of iodinated aromatics with CS bonds of thiols:

[0113]

[0114] Highly efficient and recyclable catalyst P1 photocatalyzes the coupling reaction of bromoaryl hydrocarbons with sodium sulfinate CS bonds:

[0115]

[0116] Highly efficient and recyclable catalyst P1 for photocatalytic bromination of aromatic hydrocarbons:

[0117]

[0118] Highly efficient and recyclable catalyst P1 for photocatalytic coupling reaction of bromoaryl hydrocarbons with sulfonamide CN bonds:

[0119]

[0120] Highly efficient and recyclable catalyst P1 for photocatalytic construction of CO bonds of iodinated aromatics:

[0121]

[0122] After the photocatalytic reaction is completed, methanol is added to the reaction system, and the methanol quenches the photoreaction and causes the high-efficiency recyclable catalyst P1 to precipitate from the reaction system. The reaction system is centrifuged to separate the high-efficiency recyclable catalyst P1 from the liquid phase, thereby recovering the high-efficiency recyclable catalyst P1. The recovered high-efficiency recyclable catalyst P1 can be used again for the photocatalytic reaction, and a lot of costs can be saved through repeated use.

[0123] Examples 4-8 are about using the highly efficient and recyclable catalyst P1 prepared in Example 1 to catalyze different types of photocatalytic reactions, as shown in Table 1. As a comparative experiment, the highly efficient and recyclable catalyst P1 in Examples 4-8 was replaced with the existing commercial catalyst NiCl2.DME to carry out photocatalytic reactions. The experimental results of Examples 4-8 and their respective comparative experiments are shown in Table 1.

[0124] Table 1 Catalytic test results of high-efficiency recyclable catalyst and comparative catalyst

[0125]

[0126] Figure 4 This is the nuclear magnetic resonance spectrum of the product of the photocatalytic reaction of Example 4. C-S bonds are generated after the photocatalytic reaction. The highly efficient and recyclable catalyst P1 catalyzes the reaction of Example 4.

[0127] Figure 5 This is the nuclear magnetic resonance spectrum of the product of the photocatalytic reaction of Example 5. C-S bonds are generated after the photocatalytic reaction. The highly efficient and recyclable catalyst P1 catalyzes the reaction of Example 5.

[0128] Figure 6 This is the nuclear magnetic resonance spectrum of the product of the photocatalytic reaction of Example 6. CN bonds are generated after the photocatalytic reaction, and the highly efficient and recyclable catalyst P1 catalyzes the reaction of Example 6.

[0129] Figure 7 This is the nuclear magnetic resonance spectrum of the product of the photocatalytic reaction of Example 7. CC bonds are generated after the photocatalytic reaction, and the highly efficient and recyclable catalyst P1 catalyzes the reaction of Example 7.

[0130] Figure 8 This is the nuclear magnetic resonance spectrum of the product of the photocatalytic reaction of Example 8. CO bonds are generated after the photocatalytic reaction, and the highly efficient and recyclable catalyst P1 catalyzes the reaction of Example 8.

[0131] As can be seen from Table 1, the photocatalytic reaction time of the highly efficient and recyclable catalyst P1 prepared in Example 1 is 10-12 hours, while the photocatalytic reaction time of the comparative experiment using NiCl2.DME is 24-48 hours. This is because the photosensitizer monomer and the transition metal copolymer molecule of the highly efficient and recyclable catalyst P1 are loaded on the same main chain, the relative positions of the photosensitizer monomer and the transition metal copolymer molecule are fixed, and the transition metal copolymer molecule is more likely to capture the free radicals generated by the photosensitizer, resulting in a synergistic catalytic effect, improving the catalytic activity, and shortening the reaction catalytic time.

[0132] The photocatalytic reaction yield of the highly efficient and recyclable catalyst P1 is 92-98%, while the photocatalytic reaction yield of the existing commercial catalyst NiCl2.DME is 43-70%. The catalytic efficiency of the highly efficient and recyclable catalyst P1 of the present invention is much higher than that of the existing catalyst.

[0133] The highly efficient and recyclable catalyst P1 of Example 4 was recycled and reused, and then recycled and used again, and a total of 6 catalytic-recycling cycles were performed. Fig. 9 As shown, the highly efficient and recyclable catalyst P1 is 98%, and after 6 cycles, the yield is still as high as 90%.

[0134] Although the present invention has been described in detail in general terms and in specific embodiments in this specification, it is obvious to those skilled in the art that some modifications or improvements may be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A method for preparing a highly efficient and recyclable catalyst for photocatalytic reaction, characterized in that: The structural formula of the highly efficient and recyclable catalyst is as follows: ； Wherein, R1 is an alkyl group containing 1 to 4 carbon atoms; R2 is an aryl group; 0.6<x / y<1.5; The method for preparing the highly efficient and recyclable catalyst for photocatalytic reaction comprises the following steps: S1, ammonia water and anhydrous ethanol are mixed evenly in a volume ratio of 1: (20-30), heated to 30°C for insulation, and then tetraethyl silicate is added to react at 50°C for 6-10h to obtain a silica microsphere suspension; The ratio of tetraethyl silicate to ammonia water is 1-2 mmol tetraethyl silicate / 1 ml ammonia water; S2, adding 3-aminopropyltriethoxysilane to the silica microsphere suspension, stirring and refluxing, and then collecting the precipitate by centrifugation to obtain product 1; The ratio of 3-aminopropyltriethoxysilane to ammonia water in step S1 is 2-3 mmol 3-aminopropyltriethoxysilane / 1 ml ammonia water; The structural formula of product 1 is: ; S3, dissolving NHS-CPP in DMF, stirring evenly, adding product 1, reacting for 8 hours, and collecting the precipitate by centrifugation to obtain product 2; The structural formula of product 2 is: ; S4, mixing the complex monomer, photosensitizer monomer and product 2 and dissolving them in tetrahydrofuran, adding an initiator and reacting them at 60-80° C. in a nitrogen atmosphere for 8-12 hours, and collecting the precipitate by centrifugation to obtain an intermediate product; The complex monomer structural formula is: ； R1 is methyl, ethyl, isopropyl or tert-butyl; The photosensitizer monomer structural formula is: ； R2 is phenyl, naphthyl, 4-cyanophenyl or 4-methoxyphenyl; S5, dissolving the intermediate product in tetrahydrofuran, adding nickel (II) chloride ethylene glycol dimethyl ether complex, reacting for 4-6 hours, and then collecting the precipitate by centrifugation to obtain the product.

2. The preparation method according to claim 1, characterized in that: R1 is methyl, ethyl, isopropyl or tert-butyl; R2 is phenyl, naphthyl, 4-cyanophenyl or 4-methoxyphenyl.

3. The preparation method according to claim 1, characterized in that: The molar ratio of NHS-CPP to product 1 is 1:(1-1.5).

4. The preparation method according to claim 1, characterized in that: The molar ratio of product 2, complex monomer and photosensitizer monomer is 1:(40-60):(40:60).

5. The preparation method according to claim 1, characterized in that: The molar ratio of nickel (II) chloride ethylene glycol dimethyl ether complex to product 2 is (40-60):

1.

6. The preparation method according to claim 1, characterized in that: The initiator is azobisisobutyronitrile, and the molar ratio of azobisisobutyronitrile to product 2 is 0.5:

1.

7. Use of the high-efficiency recyclable catalyst prepared by the preparation method according to any one of claims 1 to 6 in photocatalytic reactions.

8. The use according to claim 7, characterized in that: The recovery method of the highly efficient and recyclable catalyst is: After the catalytic reaction is completed, methanol is added to the reaction system to quench the reaction and precipitate the highly efficient and recyclable catalyst in the reaction system, which is then recovered by centrifugal separation.

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