Conjugated polymer tripoz organic matter, and preparation method and application thereof

Abstract

This invention discloses a conjugated polymer TRIPOZ organic compound, its preparation method, and its application. The conjugated polymer is prepared by covalent modification of tripterene and phenoxazine. Anhydrous DCE is added in stoichiometric amounts of POZ, TRI, dimethoxymethane, and anhydrous FeCl3 under an inert N2 atmosphere with continuous stirring and reflux. After the reaction is complete, the solid product is washed by centrifugation and dried to obtain the final product. The organic compound of this invention, with its rigid molecular framework and stable porous structure, has significant advantages in capacitive deionization technology. The nitrogen and oxygen heteroatoms in its structure provide pseudocapacitive active sites, significantly improving the ion adsorption capacity. Simultaneously, the robust framework and abundant pores ensure excellent cycle stability, thereby achieving efficient and durable defluorination performance.

Description

Technical Field

[0001] This invention relates to a conjugated polymer TRIPOZ organic compound, and also to a method for preparing the above-mentioned conjugated polymer TRIPOZ organic compound and its application as a capacitor deionization electrode material. Background Technology

[0002] Capacitive deionization (CDI) is a novel water treatment technology based on the principle of electroadsorption, particularly suitable for brackish water desalination, deep desalination of industrial wastewater, and drinking water purification. Its core working principle involves applying a low voltage between a pair of porous electrodes. Cations and anions in the solution migrate towards the electrodes with opposite charges under electrostatic force and are captured by the electric double layer on the electrode surface, thus removing salt. When the electrodes become saturated, the adsorbed ions can be rapidly desorbed by shorting the circuit or applying a reverse voltage, regenerating the electrodes. Compared with traditional high-energy-consuming technologies such as reverse osmosis and distillation, CDI technology has significant advantages such as low energy consumption, no secondary pollution, simple operation, and environmental friendliness, demonstrating enormous application potential in the treatment of low-to-medium salinity water.

[0003] Electrode materials are crucial in determining the desalination performance and long-term stability of CDI systems. Ideal CDI electrode materials require high specific surface area, excellent conductivity, good electrochemical stability, suitable pore structure, and low cost. To date, the most widely studied electrode materials are carbon-based materials such as activated carbon, carbon aerogels, carbon nanotubes, and graphene. These materials primarily rely on physical adsorption through an electric double layer formed by their high specific surface area, but are often limited by insufficient specific capacity. To improve desalination capacity, pseudocapacitive materials with Faraday reactions, such as transition metal oxides and conductive polymers, have been introduced into CDI systems. These materials store charge through rapid redox reactions on or near the surface, providing charge storage capacity far exceeding that of the electric double layer capacitance. However, they generally suffer from poor conductivity, structural instability during cycling, metal ion dissolution, or easy expansion and degradation, leading to unsatisfactory cycle life and rate performance. Therefore, how to synergistically improve the electric double layer capacitance and pseudocapacitance through careful material design and structural control, and fundamentally solve stability defects, is a pressing problem to be solved. Summary of the Invention

[0004] Purpose of the invention: The purpose of this invention is to provide a conjugated polymer TRIPOZ organic compound that has excellent structural stability, high defluorination capacity and high conductivity. It also provides a method for preparing the above organic compound and its application in capacitor deion electrode materials, which can not only achieve high-efficiency defluorination performance, but also show significant advantages in cycle stability.

[0005] Technical solution: The conjugated polymer TRIPOZ of the present invention is a conjugated microporous polymer with a three-dimensional rigid conjugated framework structure. It is formed by covalent modification of triterpenesene (TRI) and phenoxazine (POZ), and its structure is shown in Formula I, where n is 20~100.

[0006] .

[0007] The three-dimensional rigid conjugated framework structure of the organic material is endowed by the spatial rigidity of the tripterene units and the connection mode of the methylene bridges; its extended conjugated framework is formed by the covalent connection of the benzene ring of the tripterene and the planar fused ring of the phenoxazine, and the overlap of electron clouds. The synergistic effect of these structural units enables the material to simultaneously possess good structural stability, abundant micropores, and efficient electron transport channels.

[0008] The preparation method of the above-mentioned conjugated polymer TRIPOZ organic compound includes the following steps: phenoxazine POZ, triphenylene TRI, dimethoxymethane, and anhydrous FeCl3 are added to anhydrous dichloroethane and stirred under reflux in an inert atmosphere. After the reaction is completed, the solid product is washed by centrifugation and dried to obtain the conjugated polymer TRIPOZ organic compound. The molar ratio of triphenylene TRI, phenoxazine POZ, dimethoxymethane, and anhydrous FeCl3 is 1:2 to 4:3:4, and the reaction is carried out in 30 ml of anhydrous DCE.

[0009] The inert atmosphere is nitrogen and / or argon.

[0010] The stirring and reflux reaction temperature is room temperature, and the reaction time is 23~25h.

[0011] Application of the aforementioned conjugated polymer TRIPOZ organic compound in capacitive deionization electrode materials.

[0012] The electrode material is prepared by the following method: the conjugated polymer TRIPOZ organic material and the additives are mixed and ground to obtain a slurry; the slurry is uniformly coated on the surface of conductive carbon cloth to obtain the electrode material; the additives are binders and conductive additives, and the conjugated polymer TRIPOZ organic material, binders and conductive additives are mixed in a mass ratio of 7~8:1~2:1.

[0013] Invention Principle: This invention relates to a conjugated microporous polymer capacitive deionization electrode material based on TRI and POZ. The invention principle lies in achieving a balance between high pseudocapacitance and excellent structural stability through ingenious molecular structure design. In this polymer, the nitrogen atoms abundant in the POZ units provide a high density of redox active sites, significantly enhancing charge storage capacity through efficient and reversible Faraday reactions. Simultaneously, the rigid three-dimensional conjugated framework constructed by the TRI units not only ensures high overall electronic conductivity through extended delocalization effects, but its inherent microporous structure also greatly promotes rapid ion migration and transport kinetics. More importantly, this stable framework anchors the active sites in a persistent network, effectively suppressing structural collapse and performance degradation common during electrochemical cycling. This innovative strategy, integrating high-density active centers, efficient charge / ion transport channels, and an intrinsically stable framework, enables the material to synergistically achieve high desalination capacity, rapid adsorption rate, and long cycle life during capacitive deionization, providing a new solution for developing next-generation high-performance, durable water treatment electrode materials.

[0014] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) The nitrogen atoms in TRIPOZ have high redox activity and their high density distribution provides abundant pseudocapacitive active centers for the material, which can contribute reversible Faraday charge storage, thereby significantly improving the defluorination capacity of the electrode material; (2) The three-dimensional rigid conjugate framework structure constructed by TRIPOZ is stable and can effectively suppress the structural degradation such as swelling and collapse of the material during electrochemical cycling, ensuring the integrity of the active surface and making the electrode exhibit excellent long-term cycling stability; (3) The extended conjugate framework and the inherent micropores endowed by the three-dimensional rigid structure work together to build an efficient electron transport channel on the one hand and optimize the diffusion path of ions on the other hand, thereby greatly improving the overall charge transfer and ion adsorption / desorption kinetics. Attached Figure Description

[0015] Figure 1 The X-ray diffraction pattern of the conjugated polymer TRIPOZ organic compound obtained in Example 1;

[0016] Figure 2 Solid-state NMR of the conjugated polymer TRIPOZ organic compound obtained in Example 1;

[0017] Figure 3 The cyclic voltammetry (CV) curves of the conjugated polymer TRIPOZ organic material prepared in Example 1 when used as a capacitive deionization electrode material are shown at different scan rates.

[0018] Figure 4The charge-discharge curves (GCD) of the conjugated polymer TRIPOZ organic material prepared in Example 1 as a capacitor deionization electrode material are shown at different current densities.

[0019] Figure 5 The specific capacitance diagrams of the organic materials prepared in Examples 1-4 when used as deionized capacitor electrode materials at different current densities are shown.

[0020] Figure 6 The specific capacitance diagrams of the organic materials prepared in Comparative Examples 1-4 when used as deionized electrode materials for capacitors at different current densities are shown.

[0021] Figure 7 The conductivity curve of the conjugated polymer TRIPOZ organic compound prepared in Example 1 in a 500 mg / L sodium fluoride solution when used as a capacitive deion electrode material.

[0022] Figure 8 This is a comparison chart showing the defluorination capabilities of the organic compounds prepared in Examples 1-4 and Comparative Examples 1-4 when used as deionization electrode materials in a 500 mg / L sodium fluoride solution. Detailed Implementation

[0023] The present invention will now be described in detail with reference to specific embodiments.

[0024] Example 1

[0025] The preparation method of the conjugated polymer TRIPOZ organic compound of the present invention is as follows:

[0026] Stoichiometric amounts of TRI (254 mg, 1 mmol), POZ (549.6 mg, 3 mmol), dimethoxymethane (348 μL, 3 mmol), and anhydrous FeCl3 (648 mg, 4 mmol) were added to anhydrous DCE (30 mL), and the mixture was refluxed under an inert N2 atmosphere with continuous stirring for 24 h. The resulting solid was then filtered and washed with DCM, distilled water, methanol, tetrahydrofuran (THF), and acetone. The resulting solid powder was then heated to 110 °C in a vacuum oven for 24 h to obtain the desired polymer powder. The chemical reaction equations for the above method are shown below:

[0027] .

[0028] Figure 1The X-ray diffraction pattern of the polymer TRIPOZ shows a broadened diffuse diffraction peak at approximately 2θ = 13.7°, corresponding to the π-π stacking effect between aromatic structural unit layers. The broadened peak shape indicates short-range order in this stacking, suggesting the material exhibits an amorphous or low-crystallinity overall. Simultaneously, the sharp crystalline diffraction peaks of monomers TRI and POZ completely disappear, demonstrating that the two monomer raw materials have been successfully converted into a novel polymer through chemical reaction, disrupting the original long-range ordered crystalline structure. This structural characteristic is consistent with the design expectations for conjugated microporous polymers based on tripterene and phenoxazine; their amorphous porous structure is beneficial for exposing more active sites and providing rapid ion transport channels in capacitive deionization applications.

[0029] Figure 2 Solid-state NMR spectroscopy reveals that the chemical shift peak at 7.15 ppm is primarily attributed to the aromatic hydrogens and alkene hydrogens in the peripheral benzene ring of tripterene and the alkene structure. The signal peaks at 6.88, 6.64, and 6.51 ppm correspond to the resonance absorption of most of the aromatic hydrogens on the aromatic rings of tripterene and phenoxazine. The sharp singlet at 5.26 ppm clearly belongs to the hydrogen atom in the terminal vinyl group -CH=CH2, providing crucial evidence that the polymer retains reactive terminal functional groups. The characteristic signal at 3.65 ppm is mainly attributed to the aromatic hydrogen directly adjacent to the nitrogen atom in the phenoxazine unit and the methylene bridging hydrogen connecting the aromatic ring; the chemical shift in this region is significantly modulated by the electronegativity and conjugation effect of the nitrogen atom. The overall spectral signals are clear and well-defined, highly consistent with the target polymer structure, demonstrating the successful synthesis of a conjugated microporous framework based on tripterene and phenoxazine.

[0030] Example 2

[0031] The TRIPOZ organic conjugated polymer of this invention, compared with Example 1, has a different reflux time, and its preparation method is as follows:

[0032] Stoichiometric amounts of TRI (254 mg, 1 mmol), POZ (549.6 mg, 3 mmol), dimethoxymethane (348 μL, 3 mmol), and anhydrous FeCl3 (648 mg, 4 mmol) were added to anhydrous DCE (30 mL), and the mixture was refluxed under an inert N2 atmosphere with continuous stirring for 22 h. The resulting solid was then filtered and washed with DCM, distilled water, methanol, tetrahydrofuran (THF), and acetone. The resulting solid powder was then heated to 110 °C in a vacuum oven for 24 h to obtain the desired polymer powder.

[0033] Example 3

[0034] The conjugated polymer TRIPOZ organic compound of this invention, compared with Example 1, has a different molar ratio of TRI and POZ. Its preparation method is as follows:

[0035] Stoichiometric amounts of TRI (254 mg, 1 mmol), POZ (366.4 mg, 2 mmol), dimethoxymethane (348 μL, 3 mmol), and anhydrous FeCl3 (648 mg, 4 mmol) were added to anhydrous DCE (30 mL), and the mixture was refluxed under an inert N2 atmosphere with continuous stirring for 24 h. The resulting solid was then filtered and washed with DCM, distilled water, methanol, tetrahydrofuran (THF), and acetone. The resulting solid powder was then heated to 110 °C in a vacuum oven for 24 hours to obtain the desired polymer powder.

[0036] Example 4

[0037] The conjugated polymer TRIPOZ organic compound of this invention, compared with Example 1, has a different molar ratio of TRI and POZ. Its preparation method is as follows:

[0038] Stoichiometric amounts of TRI (254 mg, 1 mmol), POZ (732.8 mg, 4 mmol), dimethoxymethane (348 μL, 3 mmol), and anhydrous FeCl3 (648 mg, 4 mmol) were added to anhydrous DCE (30 mL), and the mixture was refluxed under an inert N2 atmosphere with continuous stirring for 24 h. The resulting solid was then filtered and washed with DCM, distilled water, methanol, tetrahydrofuran (THF), and acetone. The resulting solid powder was then heated to 110 °C in a vacuum oven for 24 hours to obtain the desired polymer powder.

[0039] Comparative Example 1

[0040] A polymeric organic compound, compared to Example 1, has a different preparation method using carbazole instead of POZ, and is prepared via the following chemical reaction equation:

[0041] .

[0042] Comparative Example 2

[0043] A polymeric organic compound, compared to Example 1, has a different raw material used in its preparation method, with thiaanthracene used instead of POZ, and is prepared via the following chemical reaction equation:

[0044] .

[0045] Comparative Example 3

[0046] A polymeric organic compound, compared with Example 1, with changes to the reaction conditions of the preparation method: heating and stirring under reflux for 24 hours, and heating temperature of 40°C.

[0047] Comparative Example 4

[0048] A polymeric organic compound, compared with Example 1, with the reaction conditions of the preparation method changed: the stirring and reflux process time was 12h.

[0049] Verify the application of the conjugated polymer TRIPOZ organic compounds obtained in Examples 1-4 and the polymer organic compounds obtained in Comparative Examples 1-4 as capacitor deionization electrode materials:

[0050] Before electrode preparation, the dried TRIPOZ organic material was ground in a mortar to ensure uniform mixing. The TRIPOZ organic material, carbon nanotubes, and polyvinylidene fluoride binder were mixed at a mass ratio of 7:2:1 and dispersed in N-methylpyrrolidone. The mixture was stirred in a high-speed mixer for 30 minutes to form a uniform slurry. The slurry was then spread evenly on carbon cloth and vacuum dried at 60°C for 12 hours to form an organic electrode sheet. The electrode sheet was used as the positive electrode of a deionization capacitor, and activated carbon was used as the negative electrode. The test was conducted in a 500 mg / L sodium fluoride solution.

[0051] pass Figures 3-4 It can be seen that the TRIPOZ organic electrode prepared in Example 1 has a yield of 0.1 A g. -1 The specific capacity at that point was 32.048 F g. -1 .

[0052] Figure 5 The specific capacitance diagrams for the organic compounds prepared in Examples 1-4, when used as deionization electrode materials in a 500 mg / L sodium fluoride solution at different current densities, are shown. Examples 2-4 are shown at 0.1 A g. -1 The specific capacities at the following values ​​were 27.564, 15.561, and 18.456 F g, respectively. -1 .

[0053] Figure 6 The specific capacitance diagrams of the organic compounds prepared in Comparative Examples 1-4 at different current densities in a 500 mg / L sodium fluoride solution are shown for their application as deionization electrode materials. The diagrams are for Comparative Examples 1-4 at 0.1 A g. -1 The specific capacities at the following values ​​were 10.987, 7.654, 12.564, and 11.715 F g, respectively. -1 .

[0054] Figure 7The graph shows the conductivity of the TRIPOZ organic electrode material prepared in Example 1 in a 500 mg / L sodium fluoride solution. The real-time concentration change of the sodium fluoride solution can be calculated, and the maximum defluorination amount is ultimately determined to be 69.92 mg / g. -1 .

[0055] from Figure 8 As can be seen, after reacting in a 500 mg / L sodium fluoride solution for 4 hours, the TRIPOZ organic compound prepared in Example 1 exhibited the strongest defluorination ability and the highest defluorination amount, reaching 69.92 mg g, when used as a capacitor deionization electrode material. -1 The defluorination amounts in Examples 2-4 were 49.68, 31.98, and 40.96 mg g, respectively. -1 The defluorination amounts of comparative examples 1-4 were 28.66, 24.42, 35.11, and 30.69 mg g, respectively. -1 .

[0056] Therefore, the organic compound of the present invention has outstanding advantages in capacitive deionization technology due to its rigid molecular skeleton and stable porous structure. The nitrogen and oxygen heteroatoms in its structure provide pseudocapacitive active sites, which significantly improve the ion adsorption capacity. At the same time, the robust skeleton and abundant pores ensure excellent cycle stability and thus achieve efficient and durable defluorination performance.

Claims

1. A conjugated polymer TRIPOZ organic compound, characterized in that, The organic compound is a conjugated microporous polymer with a three-dimensional rigid conjugated framework structure, which is formed by covalent modification of triterpenoid (TRI) and phenoxazine (POZ).

2. The conjugated polymer TRIPOZ organic compound according to claim 1, characterized in that, The organic compound has the structure shown in Formula I, where n is 20~100: 。 3. The conjugated polymer TRIPOZ organic compound according to claim 1, characterized in that, The organic compound is connected by the spatial rigidity of the triptene TRI unit and the methylene bridge. Its extended conjugated skeleton is formed by the covalent connection of the benzene ring of the triptene TRI and the planar fused ring of the phenoxazine POZ, and the overlap of electron clouds.

4. A method for preparing the conjugated polymer TRIPOZ organic compound according to claim 1, characterized in that, Includes the following steps: Phenyrazine POZ, triptene TRI, dimethoxymethane and anhydrous FeCl3 were added to anhydrous dichloroethane DCE and stirred under an inert atmosphere and refluxed. After the reaction was completed, the solid product was washed by centrifugation and dried to obtain the conjugated polymer TRIPOZ organic compound.

5. The preparation method according to claim 4, characterized in that, The molar ratio of triterpenoid TRI, phenoxazine POZ, dimethoxymethane, and anhydrous FeCl3 is 1:2 to 4:3:

4.

6. The preparation method according to claim 4, characterized in that, The general formula for synthesizing the conjugated polymer TRIPOZ organic compound is as follows: 。 7. The application of the conjugated polymer TRIPOZ organic compound of claim 1 in a capacitor deionization electrode material.

8. The application according to claim 7, characterized in that, The electrode material is prepared by mixing the conjugated polymer TRIPOZ organic matter and additives, grinding them, and then coating the slurry onto the surface of conductive carbon cloth to obtain a capacitor deionized defluorinated electrode material.

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