Electrode material based on MXene / PEDOT porous membrane and preparation method and application thereof
By constructing MXene/PEDOT porous structures on ITO-PET using a self-assembly method, the problem of poor electrochemical performance of MXene/PEDOT two-dimensional structural materials was solved, enabling the low-cost preparation of high-performance electrode materials and improving the electrochemical performance and environmental friendliness of the electrode materials.
Patent Information
- Application Number
- CN202411009739.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-25
- Publication Date
- 2026-01-27
AI Technical Summary
In existing technologies, the electrochemical performance of MXene/PEDOT two-dimensional structural materials is not ideal, and the preparation process of three-dimensional structures is complex, costly, and harmful to the environment.
MXene/PEDOT porous structures were prepared by self-assembly using the surfactant DDAB. ITO-PET was used as the current collector substrate. The three-dimensional porous structure was constructed under high humidity through a simple casting and ion exchange process, realizing the simultaneous introduction and loading of MXene and PEDOT.
Electrode materials with high specific capacitance, long cycle stability and high energy density were obtained. The preparation process is simple, low-cost and environmentally friendly.
Smart Images
Figure CN121416331A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of supercapacitor electrode materials technology, specifically to an electrode material based on MXene / PEDOT porous composite thin film, its preparation method, and its application. Background Technology
[0002] The use of portable electronic devices and equipment has driven the development of energy storage systems. Among these systems, supercapacitors stand out due to their rapid charge and discharge performance. The development of advanced electrode materials is crucial for constructing high-performance supercapacitors. Optimizing electrode performance hinges on two key breakthroughs: the selection of active materials and the construction of the structure. PEDOT:PSS, a widely used conductive polymer, has become one of the most promising electrode materials due to its tunable electrical properties, excellent redox activity, good structural stability, and biocompatibility. However, the conductivity of two-dimensional PEDOT:PSS is typically 1-2 orders of magnitude lower than that of three-dimensional structures, and the surface area of two-dimensional films is much smaller than that of three-dimensional structures, limiting its contact area with other substances such as electrolytes. Therefore, constructing three-dimensional PEDOT:PSS is an effective way to improve its performance and has excellent application prospects. Besides conductive polymers, two-dimensional layered materials such as MXene have attracted attention due to their abundant surface functional groups, high conductivity, and excellent dispersibility in many solvents. As a promising supercapacitor electrode material, it has shown strong competitiveness in energy storage and conversion applications. However, their tendency to stack between layers leads to deterioration in electrochemical performance. Constructing three-dimensional structures is one effective way to address this stacking issue. To date, researchers have developed various methods for preparing three-dimensional PEDOT and MXene, including 3D printing and template methods. While feasible, these methods typically involve the use of difficult-to-remove templates, inks with extremely strict requirements on composition and properties, large amounts of toxic reagents, complex operating procedures, and expensive raw materials and equipment. These factors limit further performance improvements and wider applications. Therefore, if a simple, inexpensive, and environmentally friendly method can be used to organically combine PEDOT, MXene, and three-dimensional structures, it will undoubtedly contribute to improving the performance of electrode materials and their practical applications. Summary of the Invention
[0003] The purpose of this invention is to provide an MXene / PEDOT porous structure loaded on indium tin oxide-modified polyethylene terephthalate (ITO-PET) and its preparation method, which can be applied to the electrodes of supercapacitors. This invention aims to solve the problems of insufficient electrochemical performance of single-component or MXene / PEDOT two-dimensional structure materials in the prior art, and the complex, costly, and environmentally harmful preparation process of MXene, PEDOT, or MXene / PEDOT-based three-dimensional structures.
[0004] This invention utilizes the surfactant bis(octadecyldimethylammonium bromide) (DDAB) to encapsulate PEDOT:PSS and MXene through a simple self-assembly process to prepare PEDOT and MXene-based composites. The two composites are dissolved in an organic solvent at a certain concentration and mixed in an appropriate ratio to form a casting liquid. ITO-PET is used as the current collector and substrate, and casting is carried out under suitable humidity conditions. The self-assembly process of water droplets is used to prepare an MXene / PEDOT-based three-dimensional porous structure. After removing DDAB through an ion exchange process, the porous structure remains intact, thereby obtaining an electrode with an MXene / PEDOT three-dimensional porous structure loaded on ITO-PET, which can be used as an electrode material for supercapacitors.
[0005] To achieve the above objectives, the present invention provides the following solution: The present invention provides an electrode material based on an MXene / PEDOT porous membrane, comprising ITO-PET and an MXene / PEDOT porous membrane attached thereto. The pores in the MXene / PEDOT porous membrane are approximately pentagonal and hexagonal in shape, with an average pore size of about 1–5 μm, exhibiting a relatively uniform size and a honeycomb-like structure. This electrode material exhibits high specific capacitance and long cycle stability, and can be used in the construction of supercapacitors. The resulting supercapacitor possesses high specific capacitance, good cycle stability, and high energy density.
[0006] This invention also provides a method for preparing an electrode material based on an MXene / PEDOT porous membrane, comprising the following steps:
[0007] (1) Disperse MXene powder in deionized water to prepare an MXene aqueous solution with a concentration of 0.1-6.0 mg / mL, dilute the PEDOT:PSS aqueous solution, and dissolve bis(octadecyl dimethyl ammonium bromide) (DDAB) in chloroform to prepare an organic solution with a concentration of 0.03-2 mg / mL;
[0008] (2) Mix the MXene aqueous solution and PEDOT aqueous solution prepared in step (1) with DDAB organic solution in a certain proportion, stir, and prepare MXene-based complex and PEDOT-based complex.
[0009] (3) Mix and dissolve the MXene-based complex and PEDOT-based complex prepared in step (2) in an organic solvent in a certain proportion to prepare an organic solution containing both MXene and PEDOT.
[0010] (4) The organic solution prepared in step (3) is poured onto ITO-PET under high humidity to prepare an MXene / PEDOT-based porous membrane loaded on ITO-PET.
[0011] (5) Dissolve p-toluenesulfonic acid in methanol to prepare a p-toluenesulfonic acid solution of a certain concentration;
[0012] (6) Immerse the ITO-PET loaded with MXene / PEDOT-based porous membrane prepared in step (4) into the p-toluenesulfonic acid solution prepared in step (5). After soaking for a certain period of time, an MXene / PEDOT porous membrane loaded on ITO-PET is prepared, which is an electrode material based on MXene / PEDOT porous membrane.
[0013] As a further preferred embodiment of the present invention, the concentration of PEDOT:PSS in step (1) is 0.1 to 3.0 mg / ml.
[0014] As a further preferred embodiment of the present invention, in step (2), the volume ratio of MXene aqueous solution to organic solution is 1:1 to 1:6; and the volume ratio of PEDOT:PSS aqueous solution to organic solution is 1:1 to 1:4.
[0015] As a further preferred embodiment of the present invention, in step (3), the concentration ratio of the MXene-based complex to the PEDOT-based complex is 1:1 to 1:5; the concentration of the MXene-based complex is 0.5 to 6.0 mg / mL; the concentration of the PEDOT-based complex is 0.5 to 30 mg / mL; and the organic solvent is chloroform, dichloromethane, and carbon disulfide.
[0016] As a further preferred embodiment of the present invention, the humidity in step (4) is 70% to 98%.
[0017] As a further preferred embodiment of the present invention, the concentration of p-toluenesulfonic acid solution in step (5) is 0.2 mol / L to 1 mol / L.
[0018] As a further preferred embodiment of the present invention, the soaking time in step (6) is 0.5 to 10 hours.
[0019] Application of an electrode material based on MXene / PEDOT porous membrane in supercapacitors.
[0020] This invention utilizes the amphiphilic substance DDAB to coat PEDOT and MXene separately, preparing a complex soluble in an organic solvent. A certain amount of these two complexes are mixed and dissolved in an organic solvent in a suitable ratio to prepare a casting solution. A certain amount of this casting solution is cast onto ITO-PET under high humidity conditions. An MXene / PEDOT-based porous membrane is prepared using a simple, easy-to-operate, low-cost, and pollution-free self-assembly process. After removing DDAB through an ion exchange process, an MXene / PEDOT porous membrane loaded on ITO-PET is obtained. The construction of a three-dimensional porous structure not only inhibits the aggregation and re-stacking of MXene but also provides a larger specific surface area, more electrochemical active sites, and more electrolyte storage space, all of which are beneficial for obtaining excellent electrochemical performance. Moreover, this invention employs a simple, inexpensive, and environmentally friendly self-assembly method to simultaneously introduce MXene and PEDOT into the porous structure and simultaneously load them onto ITO-PET, thus achieving green, low-cost, simple, and miniaturized preparation of electrode materials for supercapacitors.
[0021] The present invention discloses the following technical effects:
[0022] This invention discloses an electrode material based on an MXene / PEDOT porous membrane. The electrode material comprises an ITO-PET substrate and an MXene / PEDOT porous membrane attached thereto. The ITO-PET substrate is flexible, which helps to improve the bending resistance of the electrode, thereby constructing a flexible supercapacitor. The porous membrane has pores with shapes close to pentagons and hexagons, with an average pore size of about 1-5 μm and relatively uniform size, exhibiting a honeycomb-like structure. The introduction of the porous structure can inhibit the re-stacking of MXene, provide a larger specific surface area, more electrochemical active sites, and electrolyte storage space. Combining MXene, PEDOT, and the porous structure helps to improve the electrochemical performance of the electrode material. This electrode material exhibits high specific capacitance, long cycle stability, and excellent bending resistance. When used in the construction of supercapacitors, it achieves high specific capacitance, long cycle stability, and high energy density.
[0023] This invention utilizes a simple and easy-to-operate self-assembly process to prepare MXene / PEDOT-based porous membranes loaded on ITO-PET. By combining simple physical blending with self-assembly, the porous structure is formed simultaneously with the introduction of MXene and PEDOT. The preparation process does not involve the use of toxic, harmful, or corrosive substances, does not require complex template removal steps, and avoids performance degradation due to incomplete template removal. Therefore, the entire preparation process has advantages such as simplicity, cost savings, and environmental friendliness. In particular, the final simple ion exchange process can effectively remove amphiphilic substances and significantly improve the electrochemical performance of the electrode material. Attached Figure Description
[0024] Figure 1 This is a scanning electron microscope image of the MXene / PEDOT-based porous structure prepared in Example 1.
[0025] Figure 2 This is a scanning electron microscope image of the porous structure of MXene / PEDOT prepared in Example 1 after treatment with p-toluenesulfonic acid solution.
[0026] Figure 3 The GCD results of the MXene / PEDOT-based porous structure prepared in Example 1 before and after treatment with p-toluenesulfonic acid solution are shown.
[0027] Figure 4 The data shows the cycling stability of the electrode material based on the MXene / PEDOT porous structure prepared in Example 1 after 5000 cycles at 10 A / g. Detailed Implementation
[0028] The present invention will be further described in detail below with reference to the embodiments, but the implementation of the present invention is not limited thereto.
[0029] Example 1
[0030] (1) Disperse 2 mg MXene in 1 mL of deionized water, dilute PEDOT:PSS aqueous solution to 2 mg / mL, and disperse 2 mg DDAB in 1 mL of chloroform;
[0031] (2) Mix the MXene aqueous solution and PEDOT aqueous solution prepared in step (1) with the organic solution at a volume ratio of 1:1, stir, and prepare MXene-based complex and PEDOT-based complex.
[0032] (3) Mix and dissolve the 10 mg MXene-based complex and 20 mg PEDOT-based complex prepared in step (2) in 15 mL of chloroform to prepare an organic solution containing both MXene and PEDOT.
[0033] (4) The organic solution prepared in step (3) is poured onto ITO-PET at 75% humidity to prepare an MXene / PEDOT-based porous membrane loaded on ITO-PET.
[0034] (5) Dissolve 4.3g of p-toluenesulfonic acid in 50mL of methanol to prepare a p-toluenesulfonic acid solution;
[0035] (6) Immerse the ITO-PET loaded with MXene / PEDOT-based porous membrane prepared in step (4) into the p-toluenesulfonic acid solution prepared in step (5) for 2 hours to prepare the MXene / PEDOT porous membrane loaded on ITO-PET, i.e., the electrode material based on MXene / PEDOT porous membrane.
[0036] Figure 1 These are scanning electron microscope (SEM) images of the MXene / PEDOT-based porous structures prepared in this embodiment. Figure 1 It can be seen that the pores in the porous structure are close to circular or elliptical, and are arranged in a relatively orderly hexagonal close-packed pattern, with an average pore diameter of about 1.71 μm.
[0037] Figure 2 This is a scanning electron microscope (SEM) image of the MXene / PEDOT porous structure prepared in this embodiment after treatment with p-toluenesulfonic acid solution. Figure 2 It can be seen that after treatment, the pore walls become thinner, the pore shape is close to pentagonal and hexagonal, the average pore diameter is about 1.76μm, the size is relatively uniform, and it presents a honeycomb-like structure.
[0038] Figure 3 The GCD results of the MXene / PEDOT-based porous structure loaded on ITO-PET before and after treatment with p-toluenesulfonic acid solution prepared in this embodiment are shown below. Figure 3 It can be seen that after treatment, the specific capacitance of the electrode material increased from 96.6 F / g to 386.4 F / g, showing a higher specific capacitance.
[0039] Figure 4 The data represent the cycling stability of the MXene / PEDOT porous electrode material prepared in this embodiment after 5000 cycles at 10 A / g. Figure 4 It can be seen that the electrode material still retains 96.3% of its initial specific capacitance after 5000 cycles at 10 A / g, demonstrating excellent cycle stability.
[0040] Using this MXene / PEDOT porous base electrode material to construct an asymmetric supercapacitor, a specific capacitance of 300 F / g, 75% initial capacitance retention after 5000 cycles at 20 A / g, and an energy density of 56.34 Wh / kg at a power density of 120 W / kg were obtained.
[0041] Example 2
[0042] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference is that the concentration ratio of MXene complex and PEDOT complex in the casting liquid is reduced to 1:1. The above steps are repeated to prepare an electrode material based on the MXene / PEDOT porous structure. The electrode material prepared in this example has a pore size of 2.0 μm, a specific capacitance of 350 F / g, an initial capacitance retention rate of 93%, a specific capacitance of 280 F / g after being assembled into a supercapacitor, an initial capacitance retention rate of 73% after 5000 cycles at 20 A / g, and an energy density of 50.23 Wh / kg at a power density of 120 W / kg.
[0043] Example 3
[0044] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being that the concentration ratio of MXene complex and PEDOT complex in the casting liquid was increased to 1:5. The above steps were repeated to prepare an electrode material based on the MXene / PEDOT porous structure. The electrode material prepared in this example has a pore size of 1.55 μm, a specific capacitance of 326.3 F / g, an initial capacitance retention rate of 95%, a specific capacitance of 276 F / g after being assembled into a supercapacitor, an initial capacitance retention rate of 76% after 5000 cycles at 20 A / g, and an energy density of 50.12 Wh / kg at a power density of 120 W / kg.
[0045] Example 4
[0046] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being that the concentration of the p-toluenesulfonic acid solution was reduced to 0.2 mol / L. The above steps were repeated to prepare an electrode material based on the MXene / PEDOT porous structure. In this example, the pores of the porous structure in the electrode material are closer to circular, with an average pore size of 1.70 μm, a specific capacitance of 300 F / g, an initial capacitance retention rate of 90%, a specific capacitance of 192 F / g after being assembled into a supercapacitor, an initial capacitance retention rate of 71% after 5000 cycles at 20 A / g, and an energy density of 50.08 Wh / kg at a power density of 120 W / kg.
[0047] Example 5
[0048] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being that the concentration of the p-toluenesulfonic acid solution was increased to 1 mol / L. The above steps were repeated to prepare an electrode material based on the MXene / PEDOT porous structure. In this example, the pores of the porous structure in the electrode material are closer to pentagons or hexagons, with an average pore size of 1.8 μm, a specific capacitance of 365.3 F / g, an initial capacitance retention rate of 94.3%, a specific capacitance of 269.9 F / g after being assembled into a supercapacitor, an initial capacitance retention rate of 73.6% after 5000 cycles at 20 A / g, and an energy density of 50.36 Wh / kg at a power density of 120 W / kg.
[0049] Example 6
[0050] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being that the immersion time of the electrode material in the p-toluenesulfonic acid solution was reduced to 30 min. The above steps were repeated to prepare an electrode material based on the MXene / PEDOT porous structure. In this example, the pores of the porous structure in the electrode material are closer to circular or elliptical, with an average pore size of 1.71 μm, a specific capacitance of 303.5 F / g, an initial capacitance retention rate of 90.2%, a specific capacitance of 261.9 F / g after assembly into a supercapacitor, an initial capacitance retention rate of 71.8% after 5000 cycles at 20 A / g, and an energy density of 51.06 Wh / kg at a power density of 120 W / kg.
[0051] Example 7
[0052] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being that the immersion time of the electrode material in p-toluenesulfonic acid solution was increased to 10 hours. The above steps were repeated to prepare an electrode material based on the MXene / PEDOT porous structure. The pores in the porous structure of the electrode material prepared in this example are closer to pentagons or hexagons, with an average pore size of 1.81 μm, a specific capacitance of 370.5 F / g, an initial capacitance retention rate of 95.2%, a specific capacitance of 289 F / g after being assembled into a supercapacitor, an initial capacitance retention rate of 73% after 5000 cycles at 20 A / g, and an energy density of 52.69 Wh / kg at a power density of 120 W / kg.
[0053] Comparative Example 1
[0054] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being that the casting solution contained only the MXene complex and no PEDOT complex. The above steps were repeated to prepare an electrode material based on the MXene porous structure. The electrode material prepared in this example has a low specific capacitance and poor cycle stability.
[0055] Comparative Example 2
[0056] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being that the casting solution contained only the PEDOT complex and no MXene complex. The above steps were repeated to prepare an electrode material based on a PEDOT porous structure. The electrode material prepared in this example has a low specific capacitance and poor cycle stability.
[0057] Comparative Example 3
[0058] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being the absence of the soaking step in p-toluenesulfonic acid solution. The above steps were repeated to prepare an electrode material based on the MXene / PEDOT porous structure. The electrode material prepared in this example exhibits low specific capacitance and poor cycle stability.
[0059] Comparative Example 4
[0060] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being the soaking time in the p-toluenesulfonic acid solution was 12 hours. The above steps were repeated to prepare an electrode material based on the MXene / PEDOT porous structure. In this example, the porous structure of the electrode material was severely damaged, resulting in a lower specific capacitance and poorer cycle stability.
[0061] Comparative Example 5
[0062] Similar to Example 1, with other substances and conditions remaining unchanged, the only difference being the soaking time in the p-toluenesulfonic acid solution was 10 minutes. The above steps were repeated to prepare an electrode material based on the MXene / PEDOT porous structure. The porous structure of the electrode material prepared in this example remained intact, showing almost no significant change from the untreated state. However, the electrode material exhibited low specific capacitance and poor cycle stability.
[0063] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.
Claims
1. An electrode material based on an MXene / PEDOT porous membrane, characterized in that, It consists of an ITO-PET substrate and an MXene / PEDOT porous membrane attached thereto.
2. The electrode material based on an MXene / PEDOT porous membrane according to claim 1, characterized in that, The pores in the MXene / PEDOT porous membrane are close to pentagonal and hexagonal in shape, with an average pore size of about 1 to 5 μm. They are relatively uniform in size and exhibit a honeycomb-like structure.
3. A method for preparing an electrode material based on an MXene / PEDOT porous membrane as described in claim 1 or 2, characterized in that, Includes the following steps: (1) Disperse MXene powder in deionized water to prepare an MXene aqueous solution with a concentration of 0.1-6.0 mg / mL, dilute the PEDOT:PSS aqueous solution, and dissolve DDAB in chloroform to prepare an organic solution with a concentration of 0.03-2 mg / mL; (2) Mix the MXene aqueous solution and PEDOT aqueous solution prepared in step (1) with DDAB organic solution in a certain proportion, stir, and prepare MXene-based complex and PEDOT-based complex. (3) Mix and dissolve the MXene-based complex and PEDOT-based complex prepared in step (2) in an organic solvent in a certain proportion to prepare an organic solution containing both MXene and PEDOT. (4) The organic solution prepared in step (3) is poured onto ITO-PET under high humidity to prepare an MXene / PEDOT-based porous membrane loaded on ITO-PET. (5) Dissolve p-toluenesulfonic acid in methanol to prepare a p-toluenesulfonic acid solution of a certain concentration; (6) Immerse the ITO-PET loaded with MXene / PEDOT-based porous membrane prepared in step (4) into the p-toluenesulfonic acid solution prepared in step (5). After soaking for a certain period of time, an MXene / PEDOT porous membrane loaded on ITO-PET is prepared, which is an electrode material based on MXene / PEDOT porous membrane.
4. The method for preparing an electrode material based on an MXene / PEDOT porous membrane according to claim 3, characterized in that, In step (1), the concentration of PEDOT:PSS is 0.1–3.0 mg / ml.
5. The method for preparing an electrode material based on an MXene / PEDOT porous membrane according to claim 3, characterized in that, In step (2), the volume ratio of MXene aqueous solution to organic solution is 1:1 to 1:6; the volume ratio of PEDOT:PSS aqueous solution to organic solution is 1:1 to 1:
4.
6. The method for preparing an electrode material based on an MXene / PEDOT porous membrane according to claim 3, characterized in that, In step (3), the concentration ratio of the MXene-based complex to the PEDOT-based complex is 1:1 to 1:5; the concentration of the MXene-based complex is 0.5 to 6.0 mg / mL; the concentration of the PEDOT-based complex is 0.5 to 30 mg / mL; and the organic solvent is chloroform, dichloromethane, and carbon disulfide.
7. The method for preparing an electrode material based on an MXene / PEDOT porous membrane according to claim 3, characterized in that, In step (4), the humidity is 70%–98%.
8. The method for preparing an electrode material based on an MXene / PEDOT porous membrane according to claim 3, characterized in that, The concentration of p-toluenesulfonic acid solution in step (5) is 0.2 mol / L to 1 mol / L.
9. The method for preparing an electrode material based on an MXene / PEDOT porous membrane according to claim 3, characterized in that, The soaking time in step (6) is 0.5 to 10 hours.
10. The application of the electrode material according to claim 1 or 2 in supercapacitors.