Aggregation-induced emission material as well as preparation method and application thereof

Abstract

The invention discloses an aggregation-induced emission material as well as a preparation method and application thereof, and belongs to the technical field of preparation of aggregation-induced emission materials. The aggregation-induced emission material prepared by the invention is an organic small molecule with an aggregation-induced emission effect, and the fluorescent solar concentrator prepared by adopting the aggregation-induced emission material overcomes the problem of low efficiency of the existing fluorescent solar concentrator, especially the problem that the efficiency is greatly attenuated along with the increase of the device size.

Description

Technical Field

[0001] The present invention relates to the technical field of aggregation-induced luminescence material preparation, and in particular to an aggregation-induced luminescence material and a preparation method and application thereof. Background Art

[0002] Fluorescent solar concentrators (LSCs) are simple light energy absorption, conversion and concentration devices consisting of a thin transparent sheet with high refractive index properties in which a low concentration of luminophores (luminescent substances or fluorescent substances) are embedded. The luminophores of LSCs absorb most of the light in the solar radiation spectrum and then re-emit it at a longer wavelength through the photoluminescence (PL) process. Photoluminescence is a photochemical process that occurs in many optical and semiconductor organic and inorganic materials. In addition to containing fluorescent emitters in the host matrix, the system also relies on optical waveguide principles and additional peripheral photovoltaic (PV) cells to convert fluorescent photons into electrical energy, thereby improving the photovoltaic conversion efficiency of solar cells per unit area.

[0003] Since fluorescent materials will have self-absorption (i.e., the absorption spectrum and the emission spectrum overlap), and the fluorescence will experience multiple self-absorption during the optical waveguide process, the intensity reaching the edge of the device will be greatly reduced during the fluorescence transmission process. At the same time, the photoelectric conversion efficiency of the fluorescent solar concentrator will be greatly attenuated as the device size increases. In addition, the efficiency of the fluorescent solar concentrator is also affected by the fluorescence quantum yield of the fluorescent material itself. For example, the fluorescence quantum efficiency of molecules that emit red light (emission wavelength greater than 600nm) is low, and there is serious self-absorption. How to make the aggregation-induced luminescence material have weak self-absorption and high fluorescence quantum efficiency, so as to prepare a high-efficiency fluorescent solar concentrator, has become a technical problem that technicians in this field need to solve urgently. Summary of the invention

[0004] The purpose of the present invention is to provide an aggregation-induced emission material and a preparation method and application thereof, so as to solve the problems existing in the above-mentioned prior art.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] One of the technical solutions of the present invention is an aggregation-induced emission material, the structural formula of which is shown in formula (1):

[0007]

[0008] wherein R1 and R2 are each independently selected from H, methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, n-pentyl or n-hexyl;

[0009] R3 is selected from

[0010] Modification of R1 and R2 on the thiophene ring can change the aggregation structure of the compound, resulting in a higher fluorescence quantum efficiency in the aggregated state.

[0011] The second technical solution of the present invention is a method for preparing the above-mentioned aggregation-induced emission material, comprising the following steps:

[0012] (1) under a protective atmosphere, mixing differently substituted thiophene carboxaldehyde, phenanthrenequinone, aniline, ammonium chloride and a catalyst, carrying out a Maillard reaction under the catalytic action of an acid solution, and obtaining an intermediate after purification;

[0013] The structural formula of the differently substituted thiophene carboxaldehydes is

[0014] The structural formula of the intermediate is

[0015] (2) under a protective atmosphere, the intermediate, compound 1, 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2-yl)-2,1,3-benzothiadiazole and a solvent are uniformly mixed and subjected to a Suziki coupling reaction under alkaline conditions, and the aggregation-induced emission material is obtained after purification;

[0016] The structural formula of the compound 1 is

[0017] wherein R1 and R2 are each independently selected from H, methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, n-pentyl or n-hexyl;

[0018] X is a boronic acid group, a borate ester group, Br or I.

[0019] Furthermore, in step (1), the molar ratio of the differently substituted thiophene carboxaldehyde, phenanthrenequinone, aniline and ammonium chloride is 1:1:1:1, 1:1:2:1.5 or 1:1:2.5:1.5;

[0020] The temperature of the Maillard reaction is 120-130°C;

[0021] The catalyst includes ammonium acetate, potassium acetate or sodium acetate.

[0022] Furthermore, in step (1), the purification method comprises: quenching the crude product obtained after the Maillard reaction with water, adding dichloromethane for extraction, and separating the extract by chromatography column;

[0023] The eluent used in the chromatography column separation is a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1.

[0024] Further, in step (2), the molar ratio of the intermediate, compound 1, and 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2-yl)-2,1,3-benzothiadiazole is 1:1:1, 1.1:1:1, or 1:1:1.1;

[0025] The temperature of the Suziki coupling reaction is 90-100°C and the time is 12-36h;

[0026] The solvent is a mixed solvent of toluene and water in a volume ratio of 20:3, 4:1, 5:1 or 5:2.

[0027] Furthermore, in step (2), the purification method comprises: quenching the crude product obtained after the Suziki coupling reaction with water, adding dichloromethane for extraction, and separating the extract by chromatography column;

[0028] The eluent used for the chromatography column separation is a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1.

[0029] The structural formula of the aggregation-induced emission material is as follows:

[0030]

[0031] The third technical solution of the present invention: an application of the above-mentioned aggregation-induced emission material in the preparation of a fluorescent solar concentrator.

[0032] Technical solution four of the present invention: a fluorescent solar concentrator, comprising the above-mentioned aggregation-induced emission material.

[0033] Technical solution 5 of the present invention: A method for preparing the above-mentioned fluorescent solar concentrator comprises the following steps:

[0034] The aggregation-induced luminescence material is added into a high molecular polymer solution, mixed evenly and then coated on a substrate, and dried to obtain the fluorescent solar concentrator.

[0035] Technical solution six of the present invention: an application of the above-mentioned fluorescent solar concentrator in plant cultivation.

[0036] The present invention discloses the following technical effects:

[0037] (1) The aggregation-induced luminescence material prepared by the present invention is an organic small molecule with aggregation-induced luminescence effect. The fluorescent solar concentrator prepared by using the aggregation-induced luminescence material overcomes the problem of low efficiency of existing fluorescent solar concentrators (low red light fluorescence quantum efficiency), especially the problem of being affected by self-absorption and efficiency attenuation due to size increase (that is, the fluorescent solar concentrator prepared by the present invention has the advantages of high fluorescence quantum yield and weak self-absorption of red light,Figure 2 and Figure 6 ).

[0038] (2) The present invention designs the molecular structure of the compound, modifies and replaces the electron donor and acceptor at different chemical sites (such as the position of the alkyl chain), changes the molecular configuration and conformation of the aggregated state, thereby improving the fluorescence quantum efficiency of the molecule (compared with the solution state, the aggregated state can be increased by up to 20%), increasing the Stokes shift, and reducing self-absorption.

[0039] (3) The synthesis steps of the aggregation-induced luminescence material of the present invention are simple, and it can not only be prepared efficiently and in large quantities, but also the prepared aggregation-induced luminescence material has high fluorescence quantum efficiency, large Stokes shift, wide visible light absorption spectrum and excellent anti-photobleaching property ( Figure 6 ).

[0040] (4) By measuring the photoelectric conversion efficiency of the fluorescent solar concentrator prepared by the present invention, it is proved that the efficiency attenuation is weak when the size increases. The large-sized fluorescent solar concentrator (0.04 square meters) still maintains a photoelectric conversion efficiency of 1.7%.

[0041] (5) The fluorescent solar concentrator prepared by the present invention is combined with the outer wall of a greenhouse for greenhouse plant cultivation, which can reduce the inhibitory effect of ultraviolet light on crop growth, improve the light quality of transmitted light, promote crop photosynthesis, and increase agricultural crop yields. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0043] Figure 1 A physical picture of the fluorescent solar concentrator prepared in Example 7;

[0044] Figure 2 The fluorescence quantum yield diagrams of the fluorescent solar concentrators prepared in Example 7 (A1), Example 10 (A2), and Example 11 (A3) in different states (aggregated state and non-aggregated state);

[0045] Figure 3 This is a JV characteristic curve diagram of the fluorescent solar concentrator prepared in Example 7;

[0046] Figure 4 This is a CIE image of the fluorescent solar concentrator prepared in Example 7;

[0047] Figure 5 This is the fresh weight of plants grown in the greenhouse based on fluorescent solar concentrators of Example 13.

[0048] Figure 6 Absorption and fluorescence spectra of the fluorescent solar concentrator prepared in Example 7. DETAILED DESCRIPTION

[0049] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0050] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0051] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0052] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0053] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0054] The “parts” described in the following examples are all “parts by weight”.

[0055] Example 1

[0056] A method for preparing an aggregation-induced emission material (A1):

[0057] (1) In a N2 atmosphere, 5-bromothiophene-2-carboxaldehyde (2 mmol), phenanthrenequinone (2 mmol), aniline (2 mmol), ammonium chloride (2 mmol), and a catalyst (ammonium acetate, 2.5 mmol) were added to a 250 mL three-necked flask, and 90 mL of acetic acid was added to the system for deoxygenation. The reaction mixture was refluxed at 130° C. for reaction (Maillard reaction), and the reaction progress was tracked by TLC plate. After the reaction was completed, the reaction solution was cooled to room temperature, the obtained crude product was quenched with water, and then dichloromethane was added for extraction. The dichloromethane layer was taken to remove the solvent by reduced pressure distillation; the crude product was separated by chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1, thereby obtaining a light yellow powder product A1a (yield 95%).

[0058] (2) A1a (2 mmol), 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,1,3-benzothiadiazole (2 mmol), 1-bromo-4-(1,2,2-triphenylphenyl)benzene (2 mmol) and potassium carbonate (6 mmol) were added to 20 mL of a mixed solution of toluene and water in a volume ratio of 5:1 in a N2 atmosphere. The reaction solution was reacted at 100°C for 12 h (Suziki coupling reaction), and the reaction progress was tracked by TLC plate. After the reaction was completed, the reaction solution was cooled to room temperature, the obtained crude product was quenched with water, and then extracted with dichloromethane. The dichloromethane layer was taken to remove the solvent by reduced pressure distillation; the crude product was separated by chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1, thereby obtaining a red powder product A1 (yield 56%).

[0059] The chemical reaction equation is as follows:

[0060]

[0061] A1 hydrogen spectrum data is: 1 H NMR (500MHz, CDCl3) δ8.82(d,J=7.9Hz,1H),8.73(d,J=8.3Hz,1H),8.67(d,J=8.3Hz,1H),7.80-7.57(m,7H), 7.49(ddd,J=8.3,7.0,1.4Hz,1H),7.27-7.20(m,1H),7.12-7.07(m,1H),6.84(d,J=4.0Hz,1H),6.62(s,1H).

[0062] Example 2

[0063] A method for preparing an aggregation-induced emission material (A2):

[0064] (1) In a N2 atmosphere, 2-bromo-3-hexylthiophene-5-carboxaldehyde (2 mmol), phenanthrenequinone (2 mmol), aniline (2 mmol), ammonium chloride (2 mmol), and a catalyst (ammonium acetate, 2.5 mmol) were added to a 250 mL three-necked flask, and 90 mL of acetic acid was added to the system for deoxygenation. The reaction mixture was refluxed at 130° C. for reaction (Maillard reaction), and the reaction progress was tracked by TLC plate. After the reaction was completed, the reaction solution was cooled to room temperature, the obtained crude product was quenched with water, and then dichloromethane was added for extraction. The dichloromethane layer was taken to remove the solvent by reduced pressure distillation; the crude product was separated by chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1, thereby obtaining a light yellow powder product A2a (yield 92%).

[0065] (2) A2a (2 mmol), 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,1,3-benzothiadiazole (2 mmol), 1-bromo-4-(1,2,2-triphenylphenyl)benzene (2 mmol) and potassium carbonate (6 mmol) were added to 20 mL of a mixed solution of toluene and water in a volume ratio of 5:2 in a N2 atmosphere. The reaction solution was reacted at 100°C for 12 h (Suziki coupling reaction), and the reaction progress was tracked by TLC plate. After the reaction was completed, the reaction solution was cooled to room temperature, the obtained crude product was quenched with water, and then extracted with dichloromethane. The dichloromethane layer was taken to remove the solvent by reduced pressure distillation; the crude product was separated by chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1, thereby obtaining a red-orange powder product A2 (yield 58%).

[0066] The chemical reaction equation is as follows:

[0067]

[0068] A2 hydrogen spectrum data is: 1 H NMR(500MHz,CD2Cl2)δ8.80(dd,J=24.9,8.4Hz,3H),7.87-7.67(m,11H),7.57(t,J=7.8Hz,1H),7.33(t,J=7.7Hz,1H),7.2 9-7.08(m,18H),2.54(t,J=7.9Hz,2H),1.46(d,J=10.2Hz,2H),1.19(d,J=6.2Hz,4H),0.89(ddq,J=15.6,10.3,7.6Hz,5H).

[0069] Example 3

[0070] A method for preparing an aggregation-induced emission material (A3):

[0071] (1) In a N2 atmosphere, 5-bromo-3-hexylthiophene-2-carboxaldehyde (2 mmol), phenanthrenequinone (2 mmol), aniline (2 mmol), ammonium chloride (2 mmol), and a catalyst (ammonium acetate, 2.5 mmol) were added to a 250 mL three-necked flask, and 90 mL of acetic acid was added to the system for deoxygenation. The reaction mixture was refluxed at 130° C. for reaction (Maillard reaction), and the reaction progress was tracked by TLC plate. After the reaction was completed, the reaction solution was cooled to room temperature, the obtained crude product was quenched with water, and then dichloromethane was added for extraction. The dichloromethane layer was taken to remove the solvent by reduced pressure distillation; the crude product was separated by chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1, thereby obtaining a white powder product A3a (yield 97%).

[0072] (2) A3a (2 mmol), 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,1,3-benzothiadiazole (2 mmol), 1-bromo-4-(1,2,2-triphenylphenyl)benzene (2 mmol) and potassium carbonate (6 mmol) were added to 20 mL of a mixed solution of toluene and water in a volume ratio of 4:1 in a N2 atmosphere. The reaction solution was reacted at 100°C for 12 h (Suziki coupling reaction), and the reaction progress was tracked by TLC plate. After the reaction was completed, the reaction solution was cooled to room temperature, the obtained crude product was quenched with water, and then extracted with dichloromethane. The dichloromethane layer was taken to remove the solvent by reduced pressure distillation; the crude product was separated by chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1, thereby obtaining a red-orange powder product A3 (yield 65%).

[0073] The chemical reaction equation is as follows:

[0074]

[0075] A3 hydrogen spectrum data: red-orange powder product A3 (65%), 1H NMR (500MHz, CD2Cl2) δ8.85(t,J=7.9Hz,2H),8.78(d,J=8.4Hz,1H),8.07(s,1H),7. 82(t,J=7.5Hz,4H),7.75-7.62(m,7H),7.58(t,J=7.8Hz,1H),7.34(t,J=7.7Hz,1H) ,7.27(d,J=8.4Hz,1H),7.19(tt,J=15.7,8.4Hz,15H),7.10(d,J=6.5Hz,2H),3.03( t,J=7.9Hz,2H), 1.77(t,J=7.9Hz,2H), 1.23(t,J=7.1Hz,4H), 0.90(t,J=7.3Hz,5H).

[0076] Example 4

[0077] A method for preparing an aggregation-induced emission material (B1):

[0078] (1) Same as Example 1.

[0079] (2) A1a (2 mmol), 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,1,3-benzothiadiazole (2 mmol), 4-boronic acid triphenylamine (2 mmol) and potassium carbonate (6 mmol) were added to 20 mL of a mixed solution of toluene and water in a volume ratio of 4:1 in a N2 atmosphere. The reaction solution was reacted at 100°C for 12 h (Suziki coupling reaction), and the reaction progress was tracked by TLC plate. After the reaction was completed, the reaction solution was cooled to room temperature, the obtained crude product was quenched with water, and then extracted with dichloromethane. The dichloromethane layer was taken to remove the solvent by reduced pressure distillation; the crude product was separated by chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1, thereby obtaining product B1 (yield 68%).

[0080] Example 5

[0081] A method for preparing an aggregation-induced emission material (B2):

[0082] (1) Same as Example 2.

[0083] (2) A2a (2 mmol), 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,1,3-benzothiadiazole (2 mmol), 4-boronic acid triphenylamine (2 mmol) and potassium carbonate (6 mmol) were added to 20 mL of a mixed solution of toluene and water in a volume ratio of 4:1 in a N2 atmosphere. The reaction solution was reacted at 100°C for 12 h (Suziki coupling reaction), and the reaction progress was tracked by TLC plate. After the reaction was completed, the reaction solution was cooled to room temperature, the crude product was quenched with water, and then dichloromethane was added for extraction. The dichloromethane layer was taken to remove the solvent by reduced pressure distillation; the crude product was separated by chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1, thereby obtaining product B2 (yield 62%).

[0084] Example 6

[0085] A method for preparing an aggregation-induced emission material (B3):

[0086] (1) Same as Example 3.

[0087] (2) A3a (2 mmol), 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,1,3-benzothiadiazole (2 mmol), 4-boronic acid triphenylamine (2 mmol) and potassium carbonate (6 mmol) were added to 20 mL of a mixed solution of toluene and water in a volume ratio of 4:1 in a N2 atmosphere. The reaction solution was reacted at 100°C for 12 h (Suziki coupling reaction), and the reaction progress was tracked by TLC plate. After the reaction was completed, the reaction solution was cooled to room temperature, the obtained crude product was quenched with water, and then extracted with dichloromethane. The dichloromethane layer was taken to remove the solvent by reduced pressure distillation; the crude product was separated by chromatography using a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:1, thereby obtaining product B3 (yield 53%).

[0088] Example 7

[0089] A method for preparing a fluorescent solar concentrator:

[0090] 5 g of polymethyl methacrylate was dissolved in toluene and stirred to completely dissolve to prepare a polymer solution with a concentration of 18 wt.%. The compound A1 prepared in Example 1 was added to the polymer solution, mixed evenly, and subjected to ultrasound for 20 min to completely remove bubbles, so that the concentration of the compound A1 in the system was 3 wt.%. The obtained solution was coated on the surface of a glass substrate using a coating machine, and placed in an oven at 80° C. to evaporate the solvent and form a film for 48 h, thereby obtaining a fluorescent solar concentrator (film thickness of 20 μm).

[0091] Example 8

[0092] Same as Example 7, except that the concentration of compound A1 in the system is 2 wt.%.

[0093] Example 9

[0094] Same as Example 7, except that the concentration of compound A1 in the system is 1 wt.%.

[0095] Example 10

[0096] Same as Example 7, except that compound A1 is replaced by compound A2.

[0097] Embodiment 11

[0098] Same as Example 7, except that compound A1 is replaced by compound A3.

[0099] Example 12

[0100] Same as Example 7, except that compound A1 is replaced by compound B1.

[0101] Effect Example 1

[0102] (1) The actual picture of the fluorescent solar concentrator prepared in Example 7 is shown in Figure 1 .

[0103] (2) The fluorescence quantum yields of the fluorescent solar concentrators prepared in Example 7 (A1), Example 10 (A2), and Example 11 (A3) in different states (aggregated state and non-aggregated state) are shown in FIG. Figure 2 .

[0104] from Figure 2 It can be seen that the compounds A1 and A2 exhibit higher fluorescence quantum efficiency in the non-aggregated state (solution state) than in the aggregated state (film state). By changing the position of the alkyl chain, the A3 molecule exhibits a high fluorescence quantum yield in the aggregated state. This shows that compounds with high fluorescence quantum yields in different states can be obtained through compound structure design to adapt to different fluorescent solar concentrators.

[0105] (3) The JV characteristic curves of the fluorescent solar concentrators (of different areas) prepared in Example 7 are shown in Figure 3 .

[0106] from Figure 3 As can be seen from the figure, as the size of the fluorescent solar concentrator increases, the voltage increases and the current density decreases. According to the formula: PCE(V OC J SC The photoelectric conversion efficiency (PCE) was calculated by FF) / F0, and it was found that with the increase of size, its photoelectric conversion efficiency only slightly decayed.

[0107] (4) The CIE image of the fluorescent solar concentrator prepared in Example 7 is shown in Figure 4 .

[0108] from Figure 4 It can be seen that the fluorescent solar concentrator mainly reflects the orange color, which is not much different from AM1.5G (sunlight).

[0109] Example 13

[0110] A greenhouse construction and plant cultivation process based on fluorescent solar concentrators:

[0111] The fluorescent solar concentrator prepared in Example 11 was used to construct the glass of the greenhouse of the experimental group, and the edge of the fluorescent solar concentrator was equipped with a solar cell (including but not limited to a monocrystalline silicon solar cell, a polycrystalline silicon solar cell, a perovskite solar cell, preferably a monocrystalline silicon solar cell). The solar cell panel was connected to a battery through a circuit to store the electrical energy generated by the fluorescent solar concentrator.

[0112] The experiment was conducted in an artificial climate chamber simulating a glass greenhouse with dimensions of 30 cm long, 20 cm wide and an area of ​​600 cm. 2 . White light intensity 200umolm -2 s -1 , add 2 UVA (340nm, 8W) and 1 UVB (311nm, 15W) ultraviolet light sources. The temperature during the light period is 26℃, the temperature during the dark period is 24℃, and the humidity is 55%.

[0113] The experimental crop was lettuce, and the experimental crop seeds were purchased online. After germination and unearthing 4 days after sowing, the seedlings were transplanted, one seedling per pot, and placed under the simulated glass greenhouse. The simulated greenhouse was evenly divided into 2 areas, and each area was separated by black cardboard to obtain a relatively independent experimental space. Two pots of seedlings with consistent growth and health were planted in each area, and water and fertilizer management methods were carried out as usual. In order to obtain more accurate experimental data, ordinary glass was used as the experimental cover glass (blank group), and 2 groups of experiments were set up.

[0114] 15 days after sowing, the growth of plants was counted and photographed. Finally, the fresh weight of lettuce was counted in each experimental environment and the average value was taken. The results are shown in Figure 5 .

[0115] Compared with the blank group, the fresh weight of lettuce in the test group increased by 41.13%, indicating that the greenhouse using the fluorescent solar concentrator prepared by the present invention can improve the utilization rate of sunlight for crops and enhance the photosynthetic capacity of crops. The greenhouse using the fluorescent solar concentrator prepared by the present invention can convert part of the ultraviolet light that is not conducive to plant growth into orange-red light ( Figure 6 ), improves the quality of transmitted light, promotes crop photosynthesis, and increases agricultural crop yields.

[0116] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. An aggregation-induced emission material, characterized in that: The structural formula is shown in formula (1): wherein R1 and R2 are each independently selected from H, methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, n-pentyl or n-hexyl; R3 is selected from 2. A method for preparing the aggregation-induced emission material according to claim 1, characterized in that: The following steps are involved: (1) under a protective atmosphere, mixing differently substituted thiophene carboxaldehyde, phenanthrenequinone, aniline, ammonium chloride and a catalyst, carrying out a Maillard reaction under the catalytic action of an acid solution, and obtaining an intermediate after purification; The structural formula of the differently substituted thiophene carboxaldehydes is The structural formula of the intermediate is (2) under a protective atmosphere, the intermediate, compound 1, 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2-yl)-2,1,3-benzothiadiazole and a solvent are uniformly mixed and subjected to a Suziki coupling reaction under alkaline conditions, and the aggregation-induced emission material is obtained after purification; The structural formula of the compound 1 is wherein R1 and R2 are each independently selected from H, methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, n-pentyl or n-hexyl; X is a boronic acid group, a borate ester group, Br or I.

3. The preparation method according to claim 2, characterized in that: In step (1), the molar ratio of the differently substituted thiophene carboxaldehyde, phenanthrenequinone, aniline and ammonium chloride is 1:1:1:1, 1:1:2:1.5 or 1:1:2.5:1.5; the temperature of the Maillard reaction is 120-130° C.; The catalyst includes ammonium acetate, potassium acetate or sodium acetate.

4. The preparation method according to claim 2, characterized in that: In step (1), the purification method comprises: quenching the crude product obtained after the Maillard reaction with water, adding dichloromethane for extraction, and separating the extract by chromatography column; The eluent used for the chromatography column separation is a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:

1.

5. The preparation method according to claim 2, characterized in that: In step (2), the molar ratio of the intermediate, compound 1, and 4,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2-yl)-2,1,3-benzothiadiazole is 1:1:1, 1.1:1:1, or 1:1:1.1; The temperature of the Suziki coupling reaction is 90-100°C and the time is 12-36h; The solvent is a mixed solvent of toluene and water in a volume ratio of 20:3, 4:1, 5:1 or 5:

2.

6. The preparation method according to claim 2, characterized in that: In step (2), the purification method comprises: quenching the crude product obtained after the Suziki coupling reaction with water, adding dichloromethane for extraction, and separating the extract by chromatography column; The eluent used for the chromatography column separation is a mixed solution of dichloromethane and petroleum ether in a volume ratio of 1:

1.

7. Use of the aggregation-induced emission material according to claim 1 in the preparation of a fluorescent solar concentrator.

8. A fluorescent solar concentrator, characterized in that: The invention comprises the aggregation-induced emission material according to claim 1.

9. A method for preparing the fluorescent solar concentrator according to claim 8, characterized in that: The following steps are involved: The aggregation-induced luminescence material is added into a high molecular polymer solution, mixed evenly and then coated on a substrate, and dried to obtain the fluorescent solar concentrator.

10. Use of the fluorescent solar concentrator according to claim 8 in plant cultivation.

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