Organic porous conductive polymer schiff base, preparation method and application thereof, and capacitor
Organic porous conductive polymer Schiff bases were prepared by condensation reaction of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde and ferrocene. Combined with conductive carbon materials, the problem of poor cycle stability of Schiff base polymers was solved, and capacitor materials with high specific capacitance and good conductivity were realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GREE ALTAIRNANO NEW ENERGY INC
- Filing Date
- 2026-03-23
- Publication Date
- 2026-07-21
AI Technical Summary
Existing Schiff base polymers exhibit poor cycle stability during charge and discharge, resulting in low specific capacitance.
Using p-phenylenediamine, 4,4-biphenyldicarboxaldehyde, and ferrocene as raw materials, an organic porous conductive polymer Schiff base was prepared through a condensation reaction. Combined with conductive carbon materials, a highly conjugated network structure was constructed, and ferrocene was doped to improve the specific surface area and conductivity.
It significantly improves the specific capacitance of the capacitor, enhances the conductivity and cycle stability of the material, and ensures that a high specific capacitance is maintained during rapid charge and discharge.
Smart Images
Figure CN122427367A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electrochemical energy storage technology, and in particular to an organic porous conductive polymer Schiff base, its preparation method and application, and a capacitor. Background Technology
[0002] Schiff bases are typically formed by the condensation reaction of a carbonyl functional group (aldehyde or ketone) with a primary amine. The Schiff base condensation reaction is widely used in chemistry and biology due to its mild reaction conditions and high rate. Schiff bases are usually formed from nitrogen-containing polymers resulting from the condensation of an amine and a carbonyl group, producing a highly stable C=N double bond (bond energy approximately 615 kJ / mol). -1 Furthermore, the nitrogen element in Schiff bases can coordinate with transition metal organometallic compounds. The molecular skeleton of Schiff base polymers doped with metal compounds becomes disordered, with more defects in the covalent skeleton and a larger specific surface area, providing more pathways for ion or molecular movement and thus improving electrochemical performance.
[0003] Schiff base polymers can vary in structure and properties depending on the synthesis method and the materials selected. Some Schiff base polymers lack an ordered and stable crystal structure, which leads to the collapse of the conjugated backbone during rapid and continuous ion insertion / penetration during charge and discharge, ultimately resulting in lower cycle stability. Summary of the Invention
[0004] In view of this, the purpose of this application is to provide an organic porous conductive polymer Schiff base and a method for preparing the same, so that the Schiff base has better electrochemical performance and significantly improves its specific capacitance (F / g). Another object of this application is to provide a capacitor based on the Schiff base described in this application and its related applications in the manufacture of capacitors.
[0005] To achieve all or part of the above objectives, as a first aspect of this application, a method for preparing an organic porous conductive polymer Schiff base is provided, comprising: S1. Prepare p-phenylenediamine solution, 4,4-biphenyldicarboxaldehyde solution and ferrocene solution; S2. The p-phenylenediamine solution, 4,4-biphenyldicarboxaldehyde solution, and ferrocene solution are mixed to obtain a mixed solution; S3. The mixed solution is stirred thoroughly to react, the precipitate obtained from the reaction is separated, and the organic porous conductive polymer Schiff base is obtained after drying.
[0006] Optionally, step S2 includes: The 4,4-biphenyldicarboxaldehyde solution is mixed with the p-phenylenediamine solution to obtain a first mixed solution; Before the first mixed solution forms a precipitate, it is mixed with a ferrocene solution to obtain a second mixed solution.
[0007] Optionally, step S2 includes: The ferrocene solution is first mixed with p-phenylenediamine solution to obtain a first mixed solution. The first mixed solution is then mixed with 4,4'-biphenyldicarboxaldehyde solution for polycondensation to obtain a second mixed solution.
[0008] Optionally, the molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde and ferrocene is 1:1:(0-1.0).
[0009] Further optionally, the molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde and ferrocene is 1:1:0.4.
[0010] Optionally, the preparation method further includes adding a conductive carbon material solution to S2. More optionally, the conductive carbon material includes carbon nanotubes and / or graphene.
[0011] As a second aspect of this application, an organic porous conductive polymer Schiff base prepared by the preparation method described in this application is provided.
[0012] As a third aspect of this application, the application of the organic porous conductive polymer Schiff base described in this application as an electrode material in the preparation of capacitors is provided.
[0013] As a fourth aspect of this application, a capacitor is provided, including electrodes comprising the organic porous conductive polymer Schiff base described in this application.
[0014] This application uses p-phenylenediamine and 4,4-biphenyldicarboxaldehyde as raw materials for the synthesis of Schiff bases. Through condensation reaction, a highly conjugated polySchiff base material with a network structure is synthesized, exhibiting good electrical conductivity and chemical stability. Furthermore, by combining it with the doped metal compound ferrocene, the specific surface area and electrical conductivity of the polySchiff base material can be improved more effectively. When used as a capacitor electrode material, it can significantly improve the specific capacitance of the capacitor. Attached Figure Description
[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application. Figure 1 The image shows the ferrocene composite material Fc doped with p-phenylenediamine condensate 4,4-biphenyldicarboxaldehyde Schiff base from Example 1. 1.0 - SEM image of PDDB; Figure 2The image shown is a SEM image of the p-phenylenediamine condensate 4,4-biphenyldicarboxaldehyde Schiff base material PDDB of Example 6. Figure 3 The results shown are the CV test results for each embodiment and comparative example; Figure 4 The results shown are the GCD test results for each embodiment and comparative example. Detailed Implementation
[0016] This application discloses an organic porous conductive polymer Schiff base, its preparation method and application, and a capacitor. Those skilled in the art can refer to the content of this application and appropriately modify the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this application. The products and processes described in this application have been described through preferred embodiments. Those skilled in the art can obviously modify or appropriately change and combine the products and processes described herein without departing from the content, spirit, and scope of this application to realize and apply the technology of this application. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0017] It should be noted that, in this document, relational terms such as "first" and "second," "step 1" and "step 2," and "(1)" and "(2)" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. Moreover, the embodiments and features described in this application can be combined with each other without conflict.
[0018] Schiff bases are mainly generated through the condensation reaction of aldehydes (or ketones) and amines, with the general formula R1R2C=N-R3, where R1 and R2 represent the aldehyde or ketone moiety, and R3 represents the amine moiety. Different raw materials affect key properties of electrode materials such as conductivity, specific capacitance, and cycle stability. For example, the p-phenylenediamine-glyoxal polySchiff base disclosed in patent CN117069904A uses p-phenylenediamine and glyoxal as raw materials. When the polySchiff base prepared is used as a capacitor electrode, the specific capacitance of the capacitor is only 38.7 F / g (current density of 0.5 A / g). Therefore, by rationally selecting aldehydes and amines, constructing a polymer framework with good conductivity and stable structure, and by controlling the microstructure and electronic effects of the material through molecular design, the ion and electron transport performance can be further optimized.
[0019] To address the shortcomings of current Schiff base materials in terms of poor specific capacitance, the first aspect of this application provides a method for preparing an organic porous conductive polymer Schiff base, comprising: S1. Prepare p-phenylenediamine solution, 4,4-biphenyldicarboxaldehyde solution and ferrocene solution; S2. The p-phenylenediamine solution, 4,4-biphenyldicarboxaldehyde solution, and ferrocene solution are mixed to obtain a mixed solution; S3. The mixed solution is stirred thoroughly to react, the precipitate obtained from the reaction is separated, and the organic porous conductive polymer Schiff base is obtained after drying.
[0020] In the preparation process of this application, p-phenylenediamine provides a rigid benzene ring structure and reaction sites, constituting the basic polymer backbone. 4,4'-biphenyldicarboxaldehyde is used to extend the molecular conjugated system, enhancing electron delocalization. Its larger steric hindrance helps suppress tight π-π stacking and increase specific surface area. Both p-phenylenediamine and 4,4'-biphenyldicarboxaldehyde are rigid aromatic monomers. They form an extended conjugated polymer backbone through Schiff base condensation. The resulting large π-conjugated system is more conducive to electron delocalization and transport, thereby improving the material's conductivity. Good conductivity ensures rapid electron transfer during charging and discharging, which is crucial for high-rate performance, allowing the material to maintain a high specific capacitance even during rapid charging and discharging.
[0021] Furthermore, ferrocene doping is further selected. On the one hand, the nitrogen element in the Schiff base can undergo coordination reactions with metal compounds to form coordination compounds, thereby changing the original pore structure of the Schiff base, altering its specific surface area, facilitating ion and electron exchange in the electrolyte, and improving electrochemical performance. On the other hand, ferrocene introduces excellent redox activity, providing additional Faraday pseudocapacitance. Its steric hindrance effect can further disrupt the tight π-π packing, making the organic molecular framework more disordered or even collapsed, while also providing more active sites for ion diffusion and more channels for charge transfer and storage, thereby optimizing electrochemical performance.
[0022] In some embodiments of this application, the solutions in step S1 are prepared using organic solvents, typically alcohols such as ethanol. More specifically, at room temperature, anhydrous ethanol is used to prepare the p-phenylenediamine solution, the 4,4-biphenyldicarboxaldehyde solution, and the ferrocene solution. The p-phenylenediamine solution and the 4,4-biphenyldicarboxaldehyde solution are both unsaturated solutions with a molar ratio of 1:1.
[0023] In some embodiments of this application, step S2 includes: The 4,4-biphenyldicarboxaldehyde solution is mixed with the p-phenylenediamine solution to obtain a first mixed solution; Before the first mixed solution forms a precipitate, it is mixed with a ferrocene solution to obtain a second mixed solution. In this reaction, p-phenylenediamine undergoes a condensation reaction with a 4,4'-biphenyldicarboxaldehyde solution first, and ferrocene is incorporated before precipitate formation.
[0024] In some other embodiments of this application, step S2 includes: The ferrocene solution is first mixed with a p-phenylenediamine solution to obtain a first mixed solution. This first mixed solution is then polycondensed with a 4,4'-biphenyldicarboxaldehyde solution to obtain a second mixed solution. In this reaction, the ferrocene solution first reacts with the p-phenylenediamine solution to generate an amine monomer with a ferrocene group, which is then polycondensed with the 4,4'-biphenyldicarboxaldehyde solution, allowing the ferrocene to be incorporated as a side group or as part of the backbone.
[0025] In some embodiments of this application, the stirring time in step S4 is 5-10 hours; in other embodiments of this application, the drying conditions in step S4 are 50°C. Dry at 70℃ for 10 minutes 16h.
[0026] In some embodiments of this application, the molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde, and ferrocene is 1:1:(0-1.0). Specifically, when the molar number of ferrocene is 0, ferrocene is not doped during the synthesis of Schiff bases. In other embodiments of this application, the molar ratio parameter of ferrocene can be selected as 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, or any value between any two. In still other embodiments of this application, the molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde, and ferrocene is 1:1:0.2, 1:1:0.4, 1:1:0.6, 1:1:0.8, or 1:1:1.
[0027] In some embodiments of this application, the preparation method further includes adding a conductive carbon material solution to S2. Optionally, the conductive carbon material includes carbon nanotubes and / or graphene. Combining with the conductive carbon material can further enhance conductivity and structural stability. The carbon material can construct a three-dimensional conductive network, improving electron transport and ion migration. Simultaneously, its high mechanical strength helps suppress polymer swelling or structural collapse during cycling, thereby significantly improving rate performance and cycling stability. The conductive carbon material can be prepared using an alcohol-based organic solvent, such as ethanol.
[0028] In a second aspect of this application, an organic porous conductive polymer Schiff base prepared by the method described herein is provided. The p-phenylenediamine condensate 4,4-biphenyldicarboxaldehyde Schiff base (PDDB, undoped ferrocene) exhibits a distinctly bulk structure. The morphology of the Schiff base doped with ferrocene undergoes a significant change, gradually evolving from a bulk particulate morphology to a lamellar structure with increasing doping content. Both exhibit superior electrochemical performance compared to similar Schiff base materials.
[0029] In a third aspect of this application, based on the excellent electrochemical properties of the organic porous conductive polymer Schiff base described in this application, its application as an electrode material in the preparation of capacitors is provided.
[0030] In a fourth aspect of this application, a capacitor is provided, including an electrode comprising an organic porous conductive polymer Schiff base as described in this application. The electrode is a positive electrode, comprising a current collector and a positive electrode material coated on the current collector. The positive electrode material comprises the organic porous conductive polymer Schiff base prepared in this application, a binder, and a conductive agent.
[0031] In some embodiments of this application, the prepared organic porous conductive polymer Schiff base, binder, and conductive agent are mixed with N-methylpyrrolidone solution in a mass ratio of 8:1:1 to prepare a conductive slurry. This slurry is then uniformly coated onto a nickel foam current collector treated with propanol for oxidation, thus preparing the positive electrode of the capacitor. Using the above synthesis method, the organic porous conductive polymer Schiff base is replaced with activated carbon to prepare the negative electrode of the capacitor. A 6 mol / L potassium hydroxide solution is used as the electrolyte, and a diaphragm is inserted between the electrodes to prevent direct contact between the positive and negative electrodes. The "sandwich" is clamped between two acrylic or plastic plates, and the entire structure is fixed with screws and nuts to ensure tight contact between the layers. Wires are soldered to the nickel foam of the two electrodes using a soldering iron, and the capacitor is charged using a low-voltage DC power supply.
[0032] In the comparative experiments provided in this application, unless otherwise specified, all experimental conditions and materials remain consistent to ensure comparability. Furthermore, all materials used in this application are commercially available.
[0033] The following provides further details regarding an organic porous conductive polymer Schiff base, its preparation method, its application, and a capacitor provided in this application.
[0034] Example 1: Preparation of Schiff base-doped ferrocene composite material of p-phenylenediamine condensate 4,4-biphenyldicarboxaldehyde Step 1: Add 0.54 g of p-phenylenediamine (C6H8N2) and 1.05 g of 4,4-biphenyldicarboxaldehyde (C6H8N2) to the mixture. 14 H 10 O2) and 0.93g ferrocene (C 10 H 10 Fe) was dissolved in 100 ml of anhydrous ethanol solution. p-phenylenediamine solution was not easily dissolved at room temperature and was dissolved by heating with a heating mantle. Step 2: Pour the prepared 4,4-biphenyldicarboxaldehyde solution into the p-phenylenediamine solution to obtain a solution that turns yellowish-brown and is named solution A.
[0035] Step 3: Pour the prepared ferrocene solution into solution A from step 2 to obtain mixed solution B. The ferrocene solution should be poured into solution A before a precipitate forms in solution A. Step 4: Add a stir bar to the mixed solution B obtained in Step 3 and perform magnetic stirring at room temperature for 5 hours. Step 5: The precipitate obtained after the reaction in Step 4 is filtered, and then dried in an oven at 60 ℃ for 12 h to obtain the p-phenylenediamine condensate 4,4-biphenyldicarboxaldehyde Schiff base-doped ferrocene composite material Fc. 1.0 - PDDB, SEM images are available.Figure 1 .
[0036] Example 2: Prepared according to the process in Example 1, except that the molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde, and ferrocene was adjusted to 1:1:0.8, to produce Fc. 0.8 -PDDB.
[0037] Example 3: Prepared according to the process in Example 1, except that the molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde, and ferrocene was adjusted to 1:1:0.6, to produce Fc. 0.6 -PDDB.
[0038] Example 4: Prepared according to the process in Example 1, except that the molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde, and ferrocene was adjusted to 1:1:0.4, to produce Fc. 0.4 -PDDB.
[0039] Example 5: Prepared according to the process in Example 1, except that the molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde, and ferrocene was adjusted to 1:1:0.2, to produce Fc. 0.2 -PDDB.
[0040] Example 6: Prepared according to the process of Example 1, except that ferrocene was not doped, PDDB was prepared, and the SEM image is shown below. Figure 2 .
[0041] As can be clearly seen from the SEM image, Fc 1.0 -PDDB ( Figure 1 ) and PDDB ( Figure 2 There are significant differences between them. Figure 2 It has a distinct blocky structure. Figure 1 The morphology of the composite material with ferrocene doping changed significantly, gradually evolving from a bulk particle morphology to a lamellar structure. Figure 1 and Figure 2 This fully demonstrates the successful preparation of the polySchiff base complex formed by p-phenylenediamine condensate 4,4-biphenyldicarboxaldehyde and ferrocene doping.
[0042] Comparative Example 1: The preparation process is the same as in Example 1, except that nickel dicene is used instead of ferrocene.
[0043] Comparative Example 2: Prepared according to the process of Example 1, except that 4-methylphenylacetaldehyde is used instead of 4,4-biphenyldicarboxaldehyde.
[0044] Comparative Example 3 Prepared according to the process in Example 1, except that 4-methylbenzylamine is used instead of p-phenylenediamine.
[0045] Experimental example: Electrochemical performance testing: 1. Cyclic Voltammetry (CV) Test: Cyclic voltammetry (CV) tests were performed on the electrodes made of the materials in each example and comparative example using an electrochemical workstation. The upper and lower limit potentials were 0V-0.8V, and the scan rate was 10 mV / s. The results are as follows: Figure 3 As shown.
[0046] 2. Galvanostatic Charge-Discharge (GCD) Method: The electrodes made from the materials of each embodiment and comparative example were tested using a galvanostatic charge-discharge (GCD) method with a potential window of 0-0.5 V and a current density of 0.5 A / g. The results are as follows: Figure 4 As shown.
[0047] 3. Electrode material specific capacity calculation: According to the formula C=I T The specific capacity of each material at a current density of 0.5 A / g was calculated using ΔV / m. C represents specific capacity in F / g; I represents current in A; T represents discharge time in s; ΔV represents potential difference in V; and m represents the mass of the active material in g. The results are shown in Table 1.
[0048] Table 1
[0049] Depend on Figure 3 It can be seen that each electrode material in Examples 1-5 has a relatively symmetrical set of redox peaks. At a scan rate of 10 mV / s, the peak width and peak height of the electrodes in Examples 1-5 are larger than those in the comparative example and Example 6, and they have a larger integrated area, indicating that the electrodes in Examples 1-5 release more capacity.
[0050] Depend on Figure 4 It can be seen that at a current density of 0.5 A / g, the electrode curves of Examples 1-5 show obvious voltage plateaus on both sides of the peak, while the curves of the three comparative examples do not. This indicates that the electrodes of the examples have a certain range of charge-discharge voltage plateaus and exhibit reversible redox properties during charge and discharge. As shown in Table 1, the specific capacity of each material in Examples 1-5 is significantly higher than that in Example 6, and the specific capacity of the Fc0.4-PDDB material in Example 4 is the highest.
[0051] Based on the above experimental results, this application uses p-phenylenediamine, 4,4-biphenyldicarboxaldehyde, and ferrocene as raw materials to prepare p-phenylenediamine-4,4-biphenyldicarboxaldehyde Schiff base-doped ferrocene composites via condensation reactions. These composites exhibit good electrochemical stability and excellent electrochemical performance, with the prepared Fc0.4-PDDB composite showing the best electrochemical performance and stability. Different proportions of ferrocene doping affect the π-π stacking effect of the Schiff base basic unit structure, making the molecular framework more disordered and even collapsed. This also provides more active sites for ion diffusion and more channels for charge transfer and storage, thereby optimizing the electrochemical performance.
[0052] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.
Claims
1. A method for preparing an organic porous conductive polymer Schiff base, characterized in that, include: S1. Prepare p-phenylenediamine solution, 4,4-biphenyldicarboxaldehyde solution and ferrocene solution; S2. The p-phenylenediamine solution, 4,4-biphenyldicarboxaldehyde solution, and ferrocene solution are mixed to obtain a mixed solution; S3. The mixed solution is stirred thoroughly to react, the precipitate obtained from the reaction is separated, and the organic porous conductive polymer Schiff base is obtained after drying.
2. The preparation method according to claim 1, characterized in that, Step S2 includes: The 4,4-biphenyldicarboxaldehyde solution is mixed with the p-phenylenediamine solution to obtain a first mixed solution; Before the first mixed solution forms a precipitate, it is mixed with a ferrocene solution to obtain a second mixed solution.
3. The preparation method according to claim 1, characterized in that, Step S2 includes: The ferrocene solution is first mixed with p-phenylenediamine solution to obtain a first mixed solution. The first mixed solution is then mixed with 4,4'-biphenyldicarboxaldehyde solution for polycondensation to obtain a second mixed solution.
4. The preparation method according to claim 1, characterized in that, The molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde and ferrocene is 1:1:(0-1.0).
5. The preparation method according to claim 4, characterized in that, The molar ratio of p-phenylenediamine, 4,4-biphenyldicarboxaldehyde, and ferrocene is 1:1:0.
4.
6. The preparation method according to any one of claims 1-5, characterized in that, It also includes adding a conductive carbon material solution to S2.
7. The preparation method according to claim 6, characterized in that, The conductive carbon material includes carbon nanotubes and / or graphene.
8. The organic porous conductive polymer Schiff base prepared by the preparation method according to any one of claims 1-7.
9. The application of the organic porous conductive polymer Schiff base as an electrode material in the preparation of capacitors according to claim 8.
10. A capacitor, characterized in that, Includes an electrode, said electrode comprising the organic porous conductive polymer Schiff base of claim 8.