Synthesis method and application of three-component cyclized covalent organic framework
By synthesizing a three-component cyclized covalent organic framework and introducing phenol as the third component using the Betti and Friedel-Crafts cyclization reactions, the problems of uneven donor-acceptor distribution and interrupted charge migration pathways were solved, and efficient electrochemiluminescence detection of UO22+ was achieved.
Patent Information
- Application Number
- CN202511337830.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-18
- Publication Date
- 2025-12-09
AI Technical Summary
Existing two-component covalent organic frameworks suffer from uneven donor-acceptor distribution and interrupted charge migration pathways when detecting UO22+ in electrochemiluminescence, resulting in low ECL efficiency and expensive and complex detection equipment.
A three-component cyclized covalent organic framework was synthesized via the Betti reaction and Friedel-Crafts cyclization reaction. Electron-rich phenol was introduced as the third component to construct the three-component cyclized covalent organic framework, thereby expanding the electron-donating region and achieving structural locking.
It achieves high sensitivity and low detection limit for UO22+ detection, simplifies the synthesis steps, reduces costs, and improves ECL efficiency.
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Figure CN121086170A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of electrochemiluminescence, and particularly relates to a synthesis method and application of a three-component cyclized covalent organic framework. BACKGROUND
[0002] With the development of nuclear industry and the growing demand for nuclear energy, the consumption of uranium continues to grow globally. From uranium ore mining to radioactive waste disposal, uranium will flow into the environment, affecting the ecosystem and human health. Various mass spectrometry, spectroscopy and other instruments are widely used to detect UO2 2+ However, these detection techniques are usually complex to operate, expensive and costly. Electrochemiluminescence (ECL) is a technique that relies on the process of high-energy electron transfer between electrochemically generated species to produce light emission. This process does not require an external light source to excite, and the reaction kinetics can be precisely controlled by adjusting the applied potential. Compared with traditional optical detection methods, ECL has higher sensitivity and time resolution, and has become a powerful tool for building efficient sensing platforms.
[0003] Covalent organic frameworks (COFs) are a class of porous crystalline materials that can be modified by ligand selection and connection mode to adjust their electronic structure to construct carrier transport channels, making COFs have application potential in energy storage, gas separation and catalysis. Currently, constructing donor-acceptor type COFs connected by C=N bonds to form highly ordered charge transport networks is a core design strategy to optimize the performance of COF emitters. However, the high polarizability of C=N bonds often disrupts the planar conjugation of COFs, hindering the electron transition path and limiting the ECL efficiency. In common two-component COFs, although the ECL can be improved by increasing the contrast of donor-acceptor, the selection of monomers is limited, hindering the further development of COF emitters (R-G Luo.; X Luo.; H-C Xu.; S-S Wan.; H-F Lv.; Beier Zhou.; Y-F Wang.; T-R Liu.; C Wu.; Q-Z Chen.; S-Q Yu.; P-F Dong.; Y-X Tian.; K Xi.; S Yuan.; X-J Wu.; H-G Ju.; J-P Lei. Reticular ratchets for directing electrochemiluminescence, J. Am. Chem. Soc., 2024, 146, 16681).
[0004] The third ligand is introduced into the COF and locked in structure, and the three-component cyclized covalent organic framework is constructed, which can effectively expand the electron donor region, overcome the problems of uneven distribution of donors and acceptors in traditional two-component covalent organic frameworks, and interrupt the charge transfer path, and the three-component cyclized covalent organic framework electrochemiluminescence and the detection of UO2 2+ have not been reported. SUMMARY
[0005] In view of the deficiencies of the prior art, the present application provides a synthesis method and application of a three-component cyclized covalent organic framework, which aims to solve the problems mentioned in the background art.
[0006] In a first aspect, the present application provides a synthesis method of a three-component cyclized covalent organic framework, which uses electron-rich p-phthalaldehyde as an electron donor, electron-deficient 2,4,6-tris(4-aminophenyl)-1,3,5-triazine as an electron acceptor, and electron-rich phenol as a third component. The three-component cyclized covalent organic framework is synthesized through Betti reaction and Friedel-Crafts cyclization reaction under the catalysis of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and copper trifluoromethanesulfonate.
[0007] Further, the method specifically includes the following steps: dispersing phenol, p-phthalaldehyde, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, and copper trifluoromethanesulfonate in a mixed solution of 1,2-dichlorobenzene and n-butanol, ultrasonic treatment at room temperature, then adding an acetic acid solution, degassing and filling with O2 through three freeze-pump-thaw cycles, heating at 120ºC for 3 days in an O2 atmosphere, collecting the brown solid product by centrifugation, washing the solid product with N,N-dimethylformamide, tetrahydrofuran, and n-hexane respectively, and drying the washed solid product at 60ºC under vacuum for 12 hours to obtain the three-component cyclized covalent organic framework.
[0008] Further, the mass ratio of phenol, p-phthalaldehyde, and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine is 75:120:106; the mass ratio of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and copper trifluoromethanesulfonate is 1:4; the volume ratio of 1,2-dichlorobenzene and n-butanol is 3:7; and the concentration of the acetic acid solution is 6M.
[0009] Further, the three-component cyclized covalent organic framework is also dissolved in N,N-dimethylformamide to prepare a three-component cyclized covalent organic framework solution with a concentration of 1mM.
[0010] In a second aspect, the present application provides a three-component cyclized covalent organic framework, which is prepared by the synthesis method of the three-component cyclized covalent organic framework.
[0011] Thirdly, the present invention provides an electrochemiluminescence system based on a three-component cyclized covalent organic framework, the construction method of which includes the following steps: Step S1: Polish the glassy carbon electrode on chamois leather with alumina paste of 1.0µm, 0.3µm and 0.05µm respectively until the surface is mirror-like. Then clean it in 0.1M nitric acid, anhydrous ethanol and ultrapure water for 1 minute respectively. Dry the electrode surface with nitrogen gas to obtain a clean glassy carbon electrode surface. Step S2: Drop 10 µL of a 1 mM three-component cyclized covalent organic framework solution onto the cleaned glassy carbon electrode surface and air dry at room temperature to prepare a three-component cyclized covalent organic framework modified glassy carbon electrode, which is used as the working electrode and placed in a phosphate buffer solution containing tripropylamine together with the reference electrode and the counter electrode.
[0012] Furthermore, in step S2, the phosphate buffer solution containing tripropylamine has a pH of 7.5 and contains 0.1M potassium chloride and 20mM tripropylamine.
[0013] Fourthly, this invention provides an electrochemiluminescence system of a three-component cyclized covalent organic framework in UO2. 2+ In the detection application, a glassy carbon electrode modified with a three-component cyclized covalent organic framework was used as the working electrode, immersed in a solution containing different concentrations of UO2. 2+ In the phosphate buffer of tripropylamine, the electrochemiluminescence signal of the three-component cyclized covalent organic framework was weakened, and the degree of weakening of the electrochemiluminescence signal was related to UO2. 2+ The concentration shows a linear relationship, achieving control over UO2. 2+ Sensitive detection.
[0014] Furthermore, UO2 2+ The concentration is 0-3µM.
[0015] Furthermore, the electrochemiluminescence system of the three-component cyclized covalent organic framework for UO2 2+ The linear detection range is 0-3µM, and the detection limit is 3nM.
[0016] The present invention has the following beneficial effects: (1) The present invention constructs a three-component cyclized covalent organic framework by means of Betti reaction and Friedel-Crafts cyclization reaction.
[0017] (2) The present invention constructs a three-component cyclized covalent organic framework in one step. The synthesis method is simple and overcomes the defects of low efficiency, high cost and complicated synthesis steps of the post-modification method.
[0018] (3) The present application effectively expands the electron donor area by introducing electron-rich phenol as the third component and performing structure locking, overcomes the problems of uneven distribution of traditional two-component covalent organic frameworks of electron donors and acceptors and interruption of charge transfer path, and constructs an anode electrochemiluminescence system based on a three-component cyclized covalent organic framework.
[0019] (4) The present application discloses that the hydroxyl site in the three-component cyclized covalent organic framework can be combined with UO2 2+ , destroys the charge transfer between the COF donor-acceptor, causes the ECL signal to be quenched, and constructs a UO2 2+ electrochemiluminescence detection method.
[0020] (5) The three-component cyclized covalent organic framework electrochemiluminescence body constructed by the present application has the advantages of high sensitivity, good selectivity, and low detection limit for UO2 2+ detection. BRIEF DESCRIPTION OF DRAWINGS
[0021] The exemplary embodiments of the present application can be more completely understood by referring to the following drawings: Figure 1 is a synthesis schematic diagram of the three-component cyclized covalent organic framework Ta-PT-p'COF of Example 1 of the present application.
[0022] Figure 2 is an infrared spectrum diagram of phenol, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, p-phenylenedimethylene and Ta-PT-p'COF of Example 1 of the present application.
[0023] Figure 3 is an experimental and simulated X-ray diffraction diagram of Ta-PT-p'COF of Example 1.
[0024] Figure 4 is an ECL diagram of GCE, Ta-PT-p'COF / GCE and Ta-PT-p'COF / GCE+UO2 2+ of Example 2.
[0025] Figure 5 is an ECL intensity-time curve and a calibration curve for UO2 2+ detection of Example 2 (0, 10, 12, 17, 25, 37, 70, 120, 200, 400, 780, 1500 and 3000 nM), wherein: Figure 5 A in the above is the ECL intensity-time curve; Figure 5 B in the above is the calibration curve.
[0026] Figure 6 is an ECL intensity-time curve and a calibration curve for UO22+ selective map of the detection. DETAILED DESCRIPTION
[0027] In order to make the technical problems to be solved by the present application, technical solutions and beneficial effects clearer, the present application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application.
[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application.
[0029] The embodiment of the present application provides a synthesis method of three-component cyclization covalent organic frameworks. Electron-rich p-xylene is used as an electron donor, electron-deficient 2,4,6-tris(4-aminophenyl)-1,3,5-triazine is used as an electron acceptor, and electron-rich phenol is used as the third component. The three-component cyclization covalent organic frameworks are synthesized through Betti reaction and Friedel-Crafts cyclization reaction under the catalysis of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and copper triflate.
[0030] In some embodiments, the method specifically comprises the following steps: dispersing phenol, p-xylene, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and copper triflate in a mixed solution of 1,2-dichlorobenzene and n-butanol, ultrasonic treatment at room temperature, then adding an acetic acid solution, degassing and filling with O2 through three freeze-pump-thaw cycles, heating at 120ºC for 3 days in an O2 atmosphere, generating brown solid product, centrifuging to collect the solid product, washing the solid product with N,N-dimethylformamide, tetrahydrofuran and n-hexane respectively, and vacuum drying the washed solid product at 60ºC for 12 hours to prepare the three-component cyclization covalent organic frameworks.
[0031] In some embodiments, the mass ratio of phenol, p-xylene and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine is 75:120:106; the mass ratio of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and copper triflate is 1:4; the volume ratio of 1,2-dichlorobenzene and n-butanol is 3:7; and the concentration of the acetic acid solution is 6M.
[0032] In some embodiments, the three-component cyclization covalent organic frameworks are also dissolved in N,N-dimethylformamide to prepare a three-component cyclization covalent organic framework solution with a concentration of 1mM.
[0033] In some embodiments, the present embodiments provide a three-component cyclized covalent organic framework, which is prepared by a synthesis method of the three-component cyclized covalent organic framework.
[0034] In some embodiments, the present embodiments provide an electrochemiluminescence system based on the three-component cyclized covalent organic framework, and a construction method comprising the following steps: Step S1: polish the glassy carbon electrode with 1.0 µm, 0.3 µm and 0.05 µm alumina paste on the suede to a mirror surface, and then clean the electrode surface in 0.1 M nitric acid, anhydrous ethanol and ultrapure water respectively for 1 minute, and dry the electrode surface with nitrogen to obtain a clean glassy carbon electrode surface; Step S2: drop 10 µL of a three-component cyclized covalent organic framework solution with a concentration of 1 mM on the clean glassy carbon electrode surface, and dry at room temperature to prepare a three-component cyclized covalent organic framework modified glassy carbon electrode as a working electrode, which is placed in a tripropylamine-containing phosphate buffer solution together with a reference electrode and a counter electrode.
[0035] In some embodiments, in step S2, the pH of the tripropylamine-containing phosphate buffer solution is 7.5, containing 0.1 M potassium chloride and 20 mM tripropylamine.
[0036] It can be understood that the three-component cyclized covalent organic framework is prepared by introducing an electron-rich phenol as a third component and structure locking, which can effectively expand the electron-donating region, overcome the problem of uneven distribution of donors and acceptors in traditional two-component covalent organic frameworks and interruption of charge transfer path, so that the three-component cyclized covalent organic framework generates a strong anodic electrochemiluminescence signal.
[0037] In some embodiments, the present embodiments provide an application of the electrochemiluminescence system of the three-component cyclized covalent organic framework in the detection of UO2 2+ , in which a three-component cyclized covalent organic framework modified glassy carbon electrode is used as a working electrode, and is immersed in a tripropylamine-containing phosphate buffer solution containing different concentrations of UO2 2+ . 2+ In some embodiments, the present embodiments provide an application of the electrochemiluminescence system of the three-component cyclized covalent organic framework in the detection of UO2 2+ , in which a three-component cyclized covalent organic framework modified glassy carbon electrode is used as a working electrode, and is immersed in a tripropylamine-containing phosphate buffer solution containing different concentrations of UO2 2+ . In some embodiments, the present embodiments provide an application of the electrochemiluminescence system of the three-component cyclized covalent organic framework in the detection of UO2 2+ , in which a three-component cyclized covalent organic framework modified glassy carbon electrode is used as a working electrode, and is immersed in a tripropylamine-containing phosphate buffer solution containing different concentrations of UO2 2+ .
[0038] In some embodiments, the concentration of UO2 2+ is 0-3 µM.
[0039] In some embodiments, the electrochemiluminescence system of the three-component cyclized covalent organic framework has a detection limit of 3 nM for UO2 2+ The linear range of detection is 0-3 µM, and the detection limit is 3 nM.
[0040] Example 1: Synthesis and characterization of three-component cyclized covalent organic framework Ta-PT-p'COF 0.0075 g of phenol (p), 0.012 g of terephthaldehyde (TAPT), and 0.0106 g of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (Ta) were added as raw materials for Betti reaction into a 10 mL Pyrex tube, and 0.0014 g of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and 0.0056 g of copper triflate were added to catalyze the Friedel-Crafts cyclization reaction between the aromatic units to promote the formation of a tetrahydroquinoline ring structure, and 0.3 mL of 1,2-dichlorobenzene and 0.7 mL of n-butanol were added, and after ultrasonic treatment at room temperature, 0.1 mL of 6M acetic acid solution was added, vacuum was applied, and O2 was filled, and the mixture was heated at 120ºC for 3 days under O2 atmosphere to generate a brown solid product, the solid product was collected by centrifugation, and washed with N,N-dimethylformamide, tetrahydrofuran, and n-hexane, respectively, and the washed solid product was dried at 60ºC under vacuum for 12 hours to prepare the three-component cyclized covalent organic framework Ta-PT-p'COF.
[0041] A schematic diagram of the synthesis of the three-component cyclized covalent organic framework Ta-PT-p'COF is shown in FIG. 1. Figure 1
[0042] The infrared spectra of phenol, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, terephthaldehyde, and Ta-PT-p'COF are shown in FIG. 2. Figure 2 The results show that the characteristic absorption peaks of -CHO of terephthaldehyde and -NH2 of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine disappear in the infrared spectrum of Ta-PT-p'COF, indicating that the condensation of the two types of groups is completed in the Betti reaction. The characteristic absorption peak of phenol-OH at 3150 cm -1 -1 remains, which proves that phenol has been successfully introduced into the skeleton structure as the third component. The characteristic absorption peak of C(sp3)-N bond appears at 925 cm -1 -1, which can be attributed to the tetrahydroquinoline ring structure generated by the Friedel-Crafts cyclization reaction. The above results indicate the effective implementation of the three-component synergistic construction and cyclization reaction.
[0043] The experimental and simulated X-ray diffraction patterns of Ta-PT-p'COF are shown in FIG. 3. Figure 3 The results show that: Ta-PT-p'COF is characterized by X-ray diffraction (XRD) technology, Ta-PT-p'COF has high crystallinity, and the diffraction peak of (100) crystal face appears at 2.9°, the experimental XRD data is consistent with the simulated XRD AA stacking model, which shows that the high crystallinity Ta-PT-p'COF is successfully synthesized by the method.
[0044] Example 2: Electrochemiluminescence (ECL) system construction and performance test based on three-component cyclization covalent organic framework Ta-PT-p'COF The glassy carbon electrode (GCE) was polished to a mirror surface with 1.0 µm, 0.3 µm and 0.05 µm alumina paste on the napped leather, and then was cleaned in 0.1M nitric acid, anhydrous ethanol and ultrapure water for 1 minute, and the electrode surface was blown dry with nitrogen; Ta-PT-p'COF was dispersed in N,N-dimethylformamide solution to prepare a 1mM Ta-PT-p'COF solution, 10µL of which was dropped on the surface of GCE and dried at room temperature to prepare a Ta-PT-p'COF modified glassy carbon electrode (Ta-PT-p'COF / GCE). The Ta-PT-p'COF / GCE was used as the working electrode, together with an Ag / AgCl reference electrode and a platinum wire counter electrode, in a phosphate buffer solution with pH of 7.5, 0.1M potassium chloride and 20mM tripropylamine, and the electrochemiluminescence signal of Ta-PT-p'COF / GCE in the potential range of 0~1.2V was tested by PBCL-510 type electrochemiluminescence detector, with the test conditions being: scan rate 50mV / s, scan range 0V~1.2V (vs. Ag / AgCl), and photomultiplier voltage 1000V.
[0045] ECL curves of GCE, Ta-PT-p'COF / GCE and Ta-PT-p'COF / GCE+UO2 2+ , as shown in Figure 4 The results show that: compared with GCE (curve a), Ta-PT-p'COF / GCE produces strong anodic ECL signal (curve b), and the monomers constituting Ta-PT-p'COF do not have obvious ECL signal, indicating that the ECL signal of Ta-PT-p'COF does not come from a certain monomer. This is because the third component electron-rich phenol introduced by Betti reaction and Friedel-Crafts cyclization reaction can effectively lock the structure of Ta-PT-p'COF, effectively expand the electron donor area, overcome the problems of uneven distribution of traditional two-component COF donor and acceptor and interruption of charge transfer path, so that Ta-PT-p'COF produces strong anodic ECL signal. 2+Afterwards, the ECL signal of Ta-PT-p'COF was weakened (curve c). The above results show that the ECL system based on Ta-PT-p'COF has high efficient ECL performance, and can interact with UO2 2+ to realize the detection of UO2 2+ .
[0046] Example 3: ECL detection of UO2 2+ (1) Analysis and detection of UO2 2+ concentration Take Ta-PT-p'COF / GCE as the working electrode, together with the reference electrode and the counter electrode, and place them in the tripropylamine phosphate buffer containing different concentrations of UO2 2 + The hydroxyl sites of Ta-PT-p'COF can bind with UO2 2+ , which destroys the charge transfer between the donor-acceptor in Ta-PT-p'COF, resulting in the weakening of the ECL signal of Ta-PT-p'COF. The degree of weakening of the ECL signal is linearly related to the concentration of UO2 2+ . Based on this, an ECL detection method of UO2 2+ is constructed, which is used to detect UO2 2+ .
[0047] The ECL intensity-time curve and the calibration curve for the detection of UO2 2+ (0, 10, 12, 17, 25, 37, 70, 120, 200, 400, 780, 1500 and 3000 nM) are shown in Figure 5 , and the test conditions of ECL are the same as in Example 2. As can be seen from A in Figure 5 , with the increase of the concentration of UO2 2+ , the ECL signal of Ta-PT-p'COF gradually decreases, and the ECL signal intensity is linearly related to the concentration of UO2 2+ in the range of 0-3000 nM. The detection limit of UO2 2+ is as low as 3 nM (B in Figure 5 ). This result is better than the previous reports on the detection of UO2 2 + , for example, the fluorescence probe based on triphenylamine for UO2 2+The detection limit is 67nM (YB Zhang.;WX Gao.;N Zhao.;MH Wu.;T Wu.;XY Zhang.;JG Wang.;C Wan.;JT Shang.;XJ Shu. A novel triphenylamine-based fluorescent probe for high selectivity and sensitivity detection of UO2 2+ In water samples and living cells, Dyes. Pigm., 2025, 232, 112436); Hu et al. based on UO2 2+ Liquid crystal sensor for specific DNAases for UO2 2+ The detection limit is 25nM (CC Hu.; P Li.; ZY Wu.; FF Fan.; D Qian.; YX Yi.; SY Yang.; F-BXiao. A novel liquid crystal sensing platform for highly selective UO2 2+ Detection based on a UO2 2+ -specific DNAzyme, Anal. Methods., 2021, 13, 4732).
[0048] (2) Method selectivity UO2 2+ The selectivity map of the detection, such as Figure 6 As shown. The results show: 3μM UO2 2+ The quenching rate of the ECL signal for Ta-PT-p'COF was as high as 82%, while that for other metal ions (Cd) at 30 μM was significantly higher. 2+ Co 3+ Ca 2+ Cu 2+ Ni 2+ Fe 2+ Fe 3+ , K + , Mn 2+ Na + Mg 2+ HPO4 2- CO3 2- SO4 2-The quenching rate of the ECL signal of Ta-PT-p'COF is low, which indicates that the method has low interference on UO2 2+ The detection has good selectivity and good application prospect.
[0049] In conclusion, the present application introduces electron-rich phenol as the third component through Betti reaction and Friedel-Crafts cyclization reaction and performs structure locking, effectively expands the electron-donating region, overcomes the problem of uneven distribution of traditional two-component covalent organic frameworks and interruption of charge transfer path, and successfully constructs a novel anodic electrochemiluminescent body Ta-PT-p'COF. 2+ The combination of the hydroxyl sites in Ta-PT-p'COF and UO2 2+ destroys the charge transfer between the donor and the acceptor in Ta-PT-p'COF, resulting in the quenching of the ECL signal of Ta-PT-p'COF, and accordingly a new method for detecting UO2 2+ based on the ECL signal of Ta-PT-p'COF is constructed, the detection of UO2
[0050] The above only describes the preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A method of synthesis of a three-component cyclized covalent organic framework, characterized in that: A three-component cyclized covalent organic framework is synthesized by Betti reaction and Friedel-Crafts cyclization reaction under the catalysis of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and copper trifluoromethanesulfonate, with electron-rich p-phthalaldehyde as an electron donor, electron-deficient 2,4,6-tris(4-aminophenyl)-1,3,5-triazine as an electron acceptor, and electron-rich phenol as a third component.
2. The method of synthesis of claim 1, wherein, Specifically comprising the following steps: phenol, p-phthalaldehyde, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and copper trifluoromethanesulfonate are dispersed in a mixed solution of 1,2-dichlorobenzene and n-butanol, after ultrasonic treatment at room temperature, an acetic acid solution is added, and the solution is degassed by three freeze-pump-thaw cycles and filled with O2, and then heated at 120ºC for 3 days under O2 atmosphere to obtain a brown solid product, which is collected by centrifugation, washed with N,N-dimethylformamide, tetrahydrofuran and n-hexane respectively, and the washed solid product is dried at 60ºC under vacuum for 12 hours to obtain the three-component cyclized covalent organic framework.
3. The method of synthesis of claim 2, wherein: The mass ratio of phenol, p-phthalaldehyde and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine is 75:120:106; the mass ratio of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and copper trifluoromethanesulfonate is 1:4; the volume ratio of 1,2-dichlorobenzene and n-butanol is 3:7; and the concentration of the acetic acid solution is 6M.
4. The method of synthesis of claim 3, wherein: The three-component cyclized covalent organic framework is also dissolved in N,N-dimethylformamide to prepare a three-component cyclized covalent organic framework solution with a concentration of 1mM.
5. A three-component cyclized covalent organic framework characterized by: Prepared by the synthesis method of the three-component cyclized covalent organic framework according to any one of claims 1-4.
6. The three-component electrochemiluminescence system of the cyclic covalent organic framework based on claim 5, characterized in that, The construction method comprises the following steps: Step S1: polish the glassy carbon electrode with 1.0µm, 0.3µm and 0.05µm alumina paste on the suede to mirror surface, and then wash it in 0.1M nitric acid, anhydrous ethanol and ultrapure water respectively for 1 minute, and dry the electrode surface with nitrogen to obtain a clean glassy carbon electrode surface; Step S2: drop 10µL of the three-component cyclized covalent organic framework solution with a concentration of 1mM on the clean glassy carbon electrode surface, and dry it at room temperature to obtain a three-component cyclized covalent organic framework modified glassy carbon electrode as a working electrode, which is placed in a tripropylamine-containing phosphate buffer solution together with a reference electrode and a counter electrode.
7. The electrochemiluminescence system of a three-component cyclized covalent organic framework of claim 6, wherein: In step S2, the pH of the tripropylamine-containing phosphate buffer solution is 7.5, and it contains 0.1M potassium chloride and 20mM tripropylamine.
8. The electrochemiluminescence system of a three-component cyclized covalent organic framework of claim 7 for use in the detection of UO2 2+ application, characterized in that A three-component covalent organic framework modified glassy carbon electrode is used as a working electrode, which is immersed in a phosphate buffer solution containing different concentrations of UO2 2+ three propylamine, the electrochemiluminescence signal of the three-component covalent organic framework is weakened, and the degree of weakening of the electrochemiluminescence signal is linearly related to the concentration of UO2 2+ , realizing sensitive detection of UO2 2+ .
9. Use according to claim 8, wherein: UO2 2+ at a concentration of 0-3 µM.
10. Use according to claim 9, wherein: Electrochemiluminescence system of three-component cyclized covalent organic frameworks for UO2 2+ The linear range of detection was 0-3 µM with a limit of detection of 3 nM.