Conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material as well as preparation method and application thereof

Abstract

The invention discloses a conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material and a preparation method and application thereof, and relates to the technical field of covalent organic framework materials.The preparation method comprises the steps that firstly, an analogue of polycyanobenzene and a nitrogen-containing compound are mixed according to the mass ratio, and mixed powder is obtained after uniform grinding; then transferring the mixed powder to a magnetic boat, placing the magnetic boat in a tubular furnace, performing calcination and heat preservation under the protection of inert gas, and obtaining a precursor material after the tubular furnace is cooled to room temperature; finally, the precursor material is purified, washed and dried in vacuum, and the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc is obtained. According to the preparation method, by optimizing the reaction temperature and the reaction time and adjusting the mass ratio of the raw materials, the preparation efficiency of the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc is remarkably improved, the process is simple, the cost is low, and controllability is achieved.

Description

Technical Field

[0001] This invention relates to the field of covalent organic framework material preparation technology, specifically to a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, its preparation method, and its applications. Background Technology

[0002] Covalent organic frameworks (COFs), as a class of crystalline porous materials formed by precisely connecting organic units through strong covalent bonds, have attracted much attention in many cutting-edge fields such as gas storage and separation, efficient catalysis, sensitive sensing, and energy storage due to their excellent designability, large specific surface area, and good chemical and thermal stability, demonstrating enormous application potential. In recent years, with the continuous innovation and deepening of synthetic strategies, the structural diversity and functionalization of COFs have been significantly improved, further expanding their application scope. Among them, phthalocyanine-based nitrogen-rich two-dimensional covalent organic frameworks (2D COFs) are a class of highly promising proton-conducting materials. The core structure of phthalocyanine consists of four tightly fused isoindole units, forming a planar macrocyclic conjugated system with a unique 16-center 18-electron configuration, uniform electron cloud distribution, stable benzene ring structure, almost uniform CN bond lengths, and strong intermolecular π-π stacking interactions. These structural features endow phthalocyanine derivatives with rich physicochemical properties and excellent stability, enabling them to play an important role in high-tech fields such as supercapacitors, electrocatalysis, battery energy storage, biomedical diagnosis and treatment, and photoelectric information conversion.

[0003] However, the synthesis of current COF materials faces numerous challenges, including long synthesis cycles, high economic costs, and insufficient product purity, which severely limit their large-scale application and promotion. In particular, the preparation of free polyphthalocyanines in conjugated nitrogen-rich COFs generally suffers from complex synthesis processes, low yields, low purity, and poor stability. Therefore, there is an urgent need to propose a method for preparing conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework materials to optimize the synthesis process of free polyphthalocyanine COF materials, improve their synthesis efficiency and product purity, and promote the widespread application of COF materials in new energy fields such as proton batteries and energy storage. Summary of the Invention

[0004] The purpose of this invention is to provide a conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material, its preparation method, and its application, in order to overcome the shortcomings of existing free polyphthalocyanine COFs materials, such as complex synthesis process, low purity, and poor stability.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, specifically comprising the following steps:

[0006] S1. Mix the analogue of polycyanobenzene and the nitrogen-containing compound in a mass ratio of 1:1 to 3, grind them evenly to obtain a mixed powder;

[0007] S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Calcine and keep warm under the protection of an inert gas. Obtain the precursor material after the tube furnace cools to room temperature.

[0008] S3. The precursor material is purified, and then the purified precursor material is filtered and washed with organic solvent or water to obtain the washing product. Finally, the washing product is vacuum dried to obtain the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc.

[0009] Further, the polycyanobenzene analogue in S1 is at least one of 1,2,4,5-tetracyanobenzene, 1,3,5-tricyanobenzene, 1,2,3-tricyanobenzene, 1,4-dicyanobenzene, and 1,4-dicyanobenzene derivatives.

[0010] Furthermore, the nitrogen-containing compound in S1 is at least one of ammonium chloride, ammonium sulfate, ammonium nitrate, urea, ammonium phosphate, ammonium fluoride, and ammonium bicarbonate.

[0011] Furthermore, the grinding method in S1 is at least one of mechanical ball milling, vibration milling, air jet milling, ultrasonic milling, and sand milling; the particle size range of the mixed powder in S1 is 0.1 μm to 1000 μm.

[0012] Furthermore, the inert gas in S2 is at least one of argon, nitrogen, and helium.

[0013] Furthermore, the calcination temperature in S2 is set to 100℃~500℃, and the heating rate is 1~20℃ / min; the holding time in S2 is set to 0.5~48h.

[0014] Furthermore, the purification method in S3 is at least one of recrystallization, column chromatography, and membrane separation.

[0015] Furthermore, the organic solvent in S3 is at least one of methanol, ethanol, acetone, benzene, chloroform, N,N-dimethylformamide, and tetrahydrofuran.

[0016] The present invention also discloses a conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc, which is prepared by the aforementioned preparation method.

[0017] This invention also discloses the application of the conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material H2PPc in proton batteries.

[0018] Compared with the prior art, the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material, its preparation method, and its application provided by the present invention have the following beneficial effects:

[0019] (1) The preparation method provided by the present invention is simple and low in cost. By optimizing the reaction temperature and reaction time and adjusting the mass ratio of raw materials, the preparation efficiency of conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc is significantly improved and is controllable.

[0020] (2) The conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc prepared by the present invention has a plate-like structure, excellent physicochemical properties, good crystal structure, and high product purity.

[0021] (3) The proton battery assembled from the conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material H2PPc provided by this invention exhibits good electrochemical performance at a current density of 3Ag. -1 It can reach 62mAh g -1 Its specific capacity exhibits good stability and reversibility during long-term cycling, making it a promising candidate for various applications. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0023] Figure 1 The X-ray powder diffraction (PXRD) patterns of H2PPc provided in Examples 1 to 4 of the present invention;

[0024] Figure 2 The X-ray powder diffraction (PXRD) patterns of the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework materials provided in Embodiment 1 and Comparative Examples 1 to 4 of the present invention are shown.

[0025] Figure 3 The UV-Vis absorption spectrum of H2PPc provided in Embodiment 4 of the present invention;

[0026] Figure 4 The image shown is a scanning electron microscope (SEM) image of H2PPc provided in Embodiment 4 of the present invention.

[0027] Figure 5 The transmission electron microscope (TEM) image of H2PPc provided in Embodiment 4 of the present invention;

[0028] Figure 6The Fourier transform infrared (FTIR) spectrum of H2PPc provided in Embodiment 4 of the present invention;

[0029] Figure 7 The graph shows the cycle performance of a proton battery assembled from a solid electrolyte film prepared by H2PPc according to Example 4 of this invention. Detailed Implementation

[0030] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] Comparative Example 1:

[0032] Please see Figure 2 A method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, specifically including the following steps:

[0033] S1. Mix 100 mg of 1,2,4,5-tetracyanobenzene with a purity of not less than 98% and 300 mg of ammonium chloride with a purity of not less than 99%. Then, place the mixed 1,2,4,5-tetracyanobenzene and ammonium chloride in a ball mill for mechanical ball milling at a speed of 600 rpm for 10 min. After grinding evenly, a mixed powder with a particle size of 0.1 μm to 1000 μm is obtained.

[0034] S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Introduce argon gas to eliminate the influence of oxygen on the reaction. Then, under the protection of argon gas, heat the mixed powder to 50°C at a heating rate of 10°C / min and calcine it. Maintain the reaction at this temperature for 2 hours to ensure that the reaction proceeds fully. After the reaction is completed, cool the temperature in the tube furnace to room temperature at a cooling rate of 10°C / min to obtain the precursor material.

[0035] S3. The precursor material is purified by recrystallization. Then, the purified precursor material is filtered and washed with chloroform and N,N-dimethylformamide to remove unreacted raw materials and by-products, and the washed product is obtained. The washed product is then placed in a vacuum drying oven for vacuum drying at a temperature of 60°C. Finally, the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material is obtained.

[0036] Comparative Example 2:

[0037] Please see Figure 2 A method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, specifically including the following steps:

[0038] S1. Mix 100 mg of 1,2,4,5-tetracyanobenzene with a purity of not less than 98% and 300 mg of ammonium chloride with a purity of not less than 99%. Then, place the mixed 1,2,4,5-tetracyanobenzene and ammonium chloride in a ball mill for mechanical ball milling at a speed of 600 rpm for 10 min. After grinding evenly, a mixed powder with a particle size of 0.1 μm to 1000 μm is obtained.

[0039] S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Introduce argon gas to eliminate the influence of oxygen on the reaction. Then, under the protection of argon gas, heat the mixed powder to 60°C at a heating rate of 10°C / min and maintain the reaction at this temperature for 2 hours to ensure that the reaction proceeds fully. After the reaction is completed, cool the temperature in the tube furnace to room temperature at a cooling rate of 10°C / min to obtain the precursor material.

[0040] S3. The precursor material is purified by recrystallization. Then, the purified precursor material is filtered and washed with chloroform and N,N-dimethylformamide to remove unreacted raw materials and by-products, and the washed product is obtained. The washed product is then placed in a vacuum drying oven for vacuum drying at a temperature of 60°C. Finally, the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material is obtained.

[0041] Comparative Example 3:

[0042] Please see Figure 2 A method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, specifically including the following steps:

[0043] S1. Mix 100 mg of 1,2,4,5-tetracyanobenzene with a purity of not less than 98% and 300 mg of ammonium chloride with a purity of not less than 99%. Then, place the mixed 1,2,4,5-tetracyanobenzene and ammonium chloride in a ball mill for mechanical ball milling at a speed of 600 rpm for 10 min. After grinding evenly, a mixed powder with a particle size of 0.1 μm to 1000 μm is obtained.

[0044] S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Introduce argon gas to eliminate the influence of oxygen on the reaction. Then, under the protection of argon gas, heat the mixed powder to 80°C at a heating rate of 10°C / min and calcine it. Maintain the reaction at this temperature for 2 hours to ensure that the reaction proceeds fully. After the reaction is completed, cool the temperature in the tube furnace to room temperature at a cooling rate of 10°C / min to obtain the precursor material.

[0045] S3. The precursor material is purified by recrystallization. Then, the purified precursor material is filtered and washed with chloroform and N,N-dimethylformamide to remove unreacted raw materials and by-products, and the washed product is obtained. The washed product is then placed in a vacuum drying oven for vacuum drying at a temperature of 60°C. Finally, the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material is obtained.

[0046] Comparative Example 4:

[0047] Please see Figure 2 A method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, specifically including the following steps:

[0048] S1. Mix 100 mg of 1,2,4,5-tetracyanobenzene with a purity of not less than 98% and 300 mg of ammonium chloride with a purity of not less than 99%. Then, place the mixed 1,2,4,5-tetracyanobenzene and ammonium chloride in a ball mill for mechanical ball milling at a speed of 600 rpm for 10 min. After grinding evenly, a mixed powder with a particle size of 0.1 μm to 1000 μm is obtained.

[0049] S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Introduce argon gas to eliminate the influence of oxygen on the reaction. Then, under the protection of argon gas, heat the mixed powder to 100°C at a heating rate of 10°C / min and calcine it. Maintain the reaction at this temperature for 2 hours to ensure that the reaction proceeds fully. After the reaction is completed, cool the temperature in the tube furnace to room temperature at a cooling rate of 10°C / min to obtain the precursor material.

[0050] S3. The precursor material is purified by recrystallization. Then, the purified precursor material is filtered and washed with chloroform and N,N-dimethylformamide to remove unreacted raw materials and by-products, and the washed product is obtained. The washed product is then placed in a vacuum drying oven for vacuum drying at a temperature of 60°C. Finally, the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material is obtained.

[0051] The conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework materials prepared in Comparative Examples 1 to 4 were subjected to X-ray powder diffraction (PXRD) tests, such as... Figure 2 As shown, at reaction temperatures of 50℃, 60℃, 80℃, and 100℃, the final product still belongs to unconverted 1,2,4,5-tetracyanobenzene, and no new characteristic peaks appear. It does not belong to the target product H2PPc, indicating that the final product obtained at reaction temperatures of 50℃, 60℃, 80℃, and 100℃ is still the raw material.

[0052] Example 1:

[0053] Please see Figures 1 to 2 A method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, specifically including the following steps:

[0054] S1. A polycyanobenzene analogue and a nitrogen-containing compound are mixed at a mass ratio of 1:1 to 3 and ground evenly to obtain a mixed powder. The polycyanobenzene analogue is at least one of 1,2,4,5-tetracyanobenzene, 1,3,5-tricyanobenzene, 1,2,3-tricyanobenzene, 1,4-dicyanobenzene, and 1,4-dicyanobenzene derivatives. The nitrogen-containing compound is at least one of ammonium chloride, ammonium sulfate, ammonium nitrate, urea, ammonium phosphate, ammonium fluoride, and ammonium bicarbonate. The grinding method is at least one of mechanical ball milling, vibratory milling, air jet milling, ultrasonic milling, and sand milling. The particle size range of the mixed powder is 0.1 μm to 1000 μm.

[0055] The specific implementation method is as follows: 100 mg of 1,2,4,5-tetracyanobenzene with a purity of not less than 98% and 300 mg of ammonium chloride with a purity of not less than 99% are mixed. Then, the mixed 1,2,4,5-tetracyanobenzene and ammonium chloride are placed in a ball mill for mechanical ball milling at a speed of 600 rpm for 10 minutes. After grinding evenly, a mixed powder with a particle size of 0.1 μm to 1000 μm is obtained.

[0056] S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Calcinate and hold it at a temperature under the protection of an inert gas. After the tube furnace cools to room temperature, obtain the precursor material. The inert gas is at least one of argon, nitrogen, and helium. The calcination temperature is set to 100℃~500℃, the heating rate is 1~20℃ / min, and the holding time is set to 0.5~48h.

[0057] The specific implementation method is as follows: the mixed powder is transferred to a magnetic boat and placed in a tube furnace. Argon gas is introduced to eliminate the influence of oxygen on the reaction. Then, under the protection of argon gas, the mixed powder is calcined at 150°C at a heating rate of 10°C / min and the reaction is maintained at this temperature for 2 hours to ensure that the reaction is fully carried out. After the reaction is completed, the temperature in the tube furnace is reduced to room temperature at a cooling rate of 10°C / min to obtain the precursor material.

[0058] S3. The precursor material is purified, and then the purified precursor material is filtered and washed with an organic solvent or water to obtain a washing product. Finally, the washing product is vacuum dried to obtain the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc. The purification method is at least one of recrystallization, column chromatography, and membrane separation. The organic solvent is at least one of methanol, ethanol, acetone, benzene, chloroform, N,N-dimethylformamide, and tetrahydrofuran.

[0059] The specific implementation method is as follows: the precursor material is purified by recrystallization, and then the purified precursor material is filtered and washed with chloroform and N,N-dimethylformamide respectively to remove unreacted raw materials and by-products to obtain the washing product. The washing product is then placed in a vacuum drying oven for vacuum drying at a temperature of 60°C to finally obtain the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc.

[0060] The present invention also discloses a conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc, which is prepared by the aforementioned preparation method.

[0061] X-ray powder diffraction (PXRD) was performed on the conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material H2PPc, as shown in the results. Figure 1 and Figure 2 As shown in the test results, at a reaction temperature of 150℃, the final product exhibited characteristic peaks that differed from those of the raw material 1,2,4,5-tetracyanobenzene, indicating that the final product H2PPc contains a new crystal structure, but still contains a small amount of unconverted characteristic peaks of the raw material 1,2,4,5-tetracyanobenzene. The crystallinity of H2PPc is not high, indicating that the reaction was not fully carried out within the 2-hour reaction time.

[0062] Example 2:

[0063] Please see Figures 1 to 2 This embodiment provides a technical solution based on Embodiment 1: a method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, specifically including the following steps:

[0064] S1. Mix 100 mg of 1,2,4,5-tetracyanobenzene with a purity of not less than 98% and 300 mg of ammonium chloride with a purity of not less than 99%. Then, place the mixed 1,2,4,5-tetracyanobenzene and ammonium chloride in a ball mill for mechanical ball milling at a speed of 600 rpm for 10 min. After grinding evenly, a mixed powder with a particle size of 0.1 μm to 1000 μm is obtained.

[0065] S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Introduce argon gas to eliminate the influence of oxygen on the reaction. Then, under the protection of argon gas, calcine the mixed powder at a heating rate of 10℃ / min to 150℃ and maintain the reaction at this temperature for 4 hours to ensure that the reaction proceeds fully. After the reaction is completed, cool the temperature in the tube furnace to room temperature at a cooling rate of 10℃ / min to obtain the precursor material.

[0066] S3. The precursor material is purified by recrystallization. Then, the purified precursor material is filtered and washed with chloroform and N,N-dimethylformamide to remove unreacted raw materials and by-products, and the washed product is obtained. The washed product is then placed in a vacuum drying oven for vacuum drying at a temperature of 60°C. Finally, the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc is obtained.

[0067] The present invention also discloses a conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc, which is prepared by the aforementioned preparation method.

[0068] X-ray powder diffraction (PXRD) was performed on the conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material H2PPc, as shown in the results. Figure 1 As shown, the crystal structure and crystallinity of H2PPc after 4 hours of reaction were improved compared to those after 2 hours. The characteristic peak intensity of the raw material 1,2,4,5-tetracyanobenzene in the product was weakened, but there were still obvious residues, indicating that a longer reaction time is still needed to achieve higher crystallinity of H2PPc.

[0069] Example 3:

[0070] Please see Figures 1 to 2 This embodiment provides a technical solution based on Embodiment 1: a method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, specifically including the following steps:

[0071] S1. Mix 100 mg of 1,2,4,5-tetracyanobenzene with a purity of not less than 98% and 300 mg of ammonium chloride with a purity of not less than 99%. Then, place the mixed 1,2,4,5-tetracyanobenzene and ammonium chloride in a ball mill for mechanical ball milling at a speed of 600 rpm for 10 min. After grinding evenly, a mixed powder with a particle size of 0.1 μm to 1000 μm is obtained.

[0072] S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Introduce argon gas to eliminate the influence of oxygen on the reaction. Then, under the protection of argon gas, heat the mixed powder to 150°C at a heating rate of 10°C / min and calcine it. Maintain the reaction at this temperature for 8 hours to ensure that the reaction proceeds fully. After the reaction is completed, cool the temperature in the tube furnace to room temperature at a cooling rate of 10°C / min to obtain the precursor material.

[0073] S3. The precursor material is purified by recrystallization. Then, the purified precursor material is filtered and washed with chloroform and N,N-dimethylformamide to remove unreacted raw materials and by-products, and the washed product is obtained. The washed product is then placed in a vacuum drying oven for vacuum drying at a temperature of 60°C. Finally, the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc is obtained.

[0074] The present invention also discloses a conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc, which is prepared by the aforementioned preparation method.

[0075] X-ray powder diffraction (PXRD) was performed on the conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material H2PPc, as shown in the results. Figure 1 As shown, after 8 hours of reaction, the characteristic peaks of the H2PPc raw material almost completely disappeared, indicating that the crystallinity of H2PPc was further improved.

[0076] Example 4:

[0077] Please see Figure 1 as well as Figures 3 to 6 This embodiment provides a technical solution based on Embodiment 1: a method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, specifically including the following steps:

[0078] S1. Mix 100 mg of 1,2,4,5-tetracyanobenzene with a purity of not less than 98% and 300 mg of ammonium chloride with a purity of not less than 99%. Then, place the mixed 1,2,4,5-tetracyanobenzene and ammonium chloride in a ball mill for mechanical ball milling at a speed of 600 rpm for 10 min. After grinding evenly, a mixed powder with a particle size of 0.1 μm to 1000 μm is obtained.

[0079] S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Introduce argon gas to eliminate the influence of oxygen on the reaction. Then, under the protection of argon gas, calcine the mixed powder at a heating rate of 10℃ / min to 150℃ and maintain the reaction at this temperature for 12 hours to ensure that the reaction proceeds fully. After the reaction is completed, cool the temperature in the tube furnace to room temperature at a cooling rate of 10℃ / min to obtain the precursor material.

[0080] S3. The precursor material is purified by recrystallization. Then, the purified precursor material is filtered and washed with chloroform and N,N-dimethylformamide to remove unreacted raw materials and by-products, and the washed product is obtained. The washed product is then placed in a vacuum drying oven for vacuum drying at a temperature of 60°C. Finally, the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc is obtained.

[0081] The present invention also discloses a conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc, which is prepared by the aforementioned preparation method.

[0082] The conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material H2PPc was analyzed by X-ray powder diffraction (PXRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and ultraviolet-visible absorption spectroscopy (UV-vis). Figure 1 As shown, after 12 hours of reaction, PXRD results indicated that H2PPc exhibited the highest characteristic peak intensity and purity; Figure 4 SEM and Figure 6 TEM results showed that H2PPc has a layered structure and high crystallinity; Figure 3 In the UV-vis test, the B band in the ultraviolet light region of about 300-400 nm and the Q band in the visible light region of about 600-700 nm are characteristic absorption bands of phthalocyanine compounds. In addition, the appearance of the B band also proves that H2PPc has a conjugated system. Figure 5 Infrared spectra of H2PPc show that the concentrations in the 1600–1700 cm⁻¹ range are... -1 There is an absorption peak for the stretching vibration of the C=N bond at 1000–1300 cm⁻¹. -1 The presence of a stretching vibration absorption peak at the CN bond indicates the presence of a nitrogen-containing heterocyclic structure in the H2PPc molecule.

[0083] Example 5:

[0084] Please see Figure 7 Application of H2PPc, a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, in proton batteries.

[0085] The conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material H2PPc prepared in Example 4 was used to prepare a solid electrolyte film. Using quinone compounds such as anthraquinone and its derivatives as the positive electrode and activated carbon as the negative electrode, the prepared solid electrolyte film was sandwiched between the positive and negative electrode materials using an adhesive encapsulation method to assemble a proton battery. The proton battery performance was then tested. During assembly, care was taken to avoid short circuits and contamination, and to ensure the battery's airtightness. Figure 7 As shown, the prepared proton battery operates at a current density of 3Ag.-1 The hourly discharge specific capacity can reach 62mAh g. -1 The charging specific capacity is similar, indicating that the battery has good energy storage capacity at the beginning of cycling, placing it at a leading level in the field of proton batteries. Moreover, after 20 cycles, the specific capacity of the proton battery remains at a relatively stable level, with performance gradually stabilizing and exhibiting good cycle stability.

[0086] The coulombic efficiency of this proton battery rapidly reached nearly 100% in the early stages of cycling, indicating that the battery has high charge transfer efficiency during charging and discharging, with almost all the charge being effectively utilized and few side reactions. Throughout the entire cycle, the coulombic efficiency remained close to 100% without significant fluctuations or a downward trend, further demonstrating that the proton battery using the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc as the solid electrolyte film has good stability and reversibility during long-term cycling.

[0087] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material, characterized in that, Specifically, the following steps are included: S1. Mix the analogue of polycyanobenzene and the nitrogen-containing compound in a mass ratio of 1:1 to 3, grind them evenly to obtain a mixed powder; S2. Transfer the mixed powder to a magnetic boat and place it in a tube furnace. Calcine and keep warm under the protection of an inert gas. Obtain the precursor material after the tube furnace cools to room temperature. S3. The precursor material is purified, and then the purified precursor material is filtered and washed with organic solvent or water to obtain the washing product. Finally, the washing product is vacuum dried to obtain the conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material H2PPc.

2. The method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material according to claim 1, characterized in that, The polycyanobenzene analogue in S1 is at least one of 1,2,4,5-tetracyanobenzene, 1,3,5-tricyanobenzene, 1,2,3-tricyanobenzene, 1,4-dicyanobenzene, and 1,4-dicyanobenzene derivatives.

3. The method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material according to claim 1, characterized in that, The nitrogen-containing compound in S1 is at least one of ammonium chloride, ammonium sulfate, ammonium nitrate, urea, ammonium phosphate, ammonium fluoride, and ammonium bicarbonate.

4. The method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material according to claim 1, characterized in that, The grinding method in S1 is at least one of mechanical ball milling, vibration milling, air jet milling, ultrasonic milling, and sand milling; the particle size range of the mixed powder in S1 is 0.1um to 1000um.

5. The method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material according to claim 1, characterized in that, The inert gas in S2 is at least one of argon, nitrogen, and helium.

6. The method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material according to claim 1, characterized in that, The calcination temperature in S2 is set to 100℃~500℃, and the heating rate is 1~20℃ / min; the holding time in S2 is set to 0.5~48h.

7. The method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material according to claim 1, characterized in that, The purification method in S3 is at least one of recrystallization, column chromatography, and membrane separation.

8. The method for preparing a conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material according to claim 1, characterized in that, The organic solvent in S3 is at least one of methanol, ethanol, acetone, benzene, chloroform, N,N-dimethylformamide, and tetrahydrofuran.

9. A conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material H2PPc, characterized in that, It is applicable to the preparation method of a conjugated nitrogen-rich metal-free polyphthalocyanine covalent organic framework material as described in any one of claims 1-8.

10. The application of the conjugated nitrogen-rich, metal-free polyphthalocyanine covalent organic framework material H2PPc according to claim 9 in proton batteries.

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