Two-dimensional carbon-based conductive polymer nanosheet array composite material, preparation method and application

Abstract

The invention belongs to the field of nano materials, and particularly relates to a two-dimensional carbon-based conductive polymer nanosheet array composite material, a preparation method and application. The preparation method of the two-dimensional carbon-based conductive polymer nanosheet array composite material comprises the following steps: dispersing a two-dimensional carbon-based material into a hydrochloric acid aqueous solution; adding potassium permanganate for hydrothermal reaction; centrifuging and drying; dispersing into a hydrochloric acid aqueous solution, adding a conductive polymer monomer, and carrying out oxidative polymerization reaction; and centrifuging and drying. According to the invention, MnO2 is used for in-situ construction of a two-dimensional array structure on the surface of a carbon base, ordered growth of a conductive polymer is guided, oxidative polymerization and doping are realized at the same time, and high structure controllability and conductivity are obtained. The prepared composite material has excellent specific surface area and electron transmission performance, the gas response value and stability are remarkably improved, the process is simple and convenient, and the method is suitable for large-scale application.

Description

Technical Field

[0001] The present invention belongs to the field of nanomaterials, and particularly relates to a two-dimensional carbon-based conductive polymer nanosheet array composite material, a preparation method and an application thereof. Background Art

[0002] Two-dimensional carbon-based materials, such as graphene, graphene oxide, and MXene, etc., due to their excellent specific surface area, high electron mobility, and good surface modifiability, have broad application prospects in the fields of heterogeneous catalysis, energy storage, sensing, and antibacterial. In the field of gas sensing, such materials provide abundant gas adsorption sites and fast electron transport paths, which contribute to achieving high-sensitivity and low-detection-limit responses.

[0003] Conductive polymers are a class of functional polymer materials with a π-conjugated structure, such as polypyrrole, polyaniline, polyindole, etc. Their chemical properties can be dynamically regulated through the doping / dedoping process, and they have good responsiveness and processing adaptability. Combining conductive polymers with two-dimensional carbon-based materials can improve the carrier migration efficiency by constructing a heterojunction interface, and at the same time introduce molecular recognition and functional group selectivity to improve the sensitivity and selectivity of gas response.

[0004] However, in the prior art, the combination of conductive polymers and carbon-based materials is usually carried out by physical mixing, simple deposition, or disordered polymerization, etc. The resulting composite materials lack regular nanostructures, and the conductive polymers often cover the carbon-based surface in a bulk or amorphous form, resulting in the shielding of active sites and the difficulty in effectively exerting the interfacial synergistic effect. In addition, due to the lack of structure guidance and reaction control means, the controllable assembly and batch stability of the materials are poor, and it is difficult to meet the requirements of high-performance and high-consistency sensing applications.

[0005] Therefore, there is an urgent need to develop a construction method for two-dimensional carbon-based conductive polymer nanoarray composite materials with controllable structure, ordered interface, and excellent response performance to break through the bottleneck of the existing preparation methods in terms of performance improvement. Summary of the Invention

[0006] In view of the problems in the prior art such as poor controllability of the structure of conductive polymers and insufficient sensitivity of composite materials, the technical problem to be solved by the present invention is to provide a two-dimensional carbon-based conductive polymer nanosheet array composite material with ordered structure and adjustable performance and a preparation method thereof. This method generates a cross-shaped manganese dioxide nanosheet array in-situ on the surface of the carbon-based material with potassium permanganate, and uses manganese dioxide as both a structure guiding agent and an oxidation initiator during the oxidative polymerization process to guide the in-situ polymerization growth of conductive polymer monomers on its surface. By adjusting the types of monomers used, two-dimensional array composite materials with different electronic structures and response characteristics can be flexibly prepared, significantly improving the performance of the materials in applications such as gas sensing.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for preparing a two-dimensional carbon-based conductive polymer nanosheet array composite material, comprising the following steps:

[0009] Disperse the two-dimensional carbon-based material into an aqueous hydrochloric acid solution;

[0010] Add potassium permanganate for hydrothermal reaction;

[0011] Centrifuge and dry;

[0012] Disperse it into an aqueous hydrochloric acid solution, add a conductive polymer monomer, and carry out an oxidative polymerization reaction;

[0013] Centrifuge and dry.

[0014] Preferably, a method for preparing a two-dimensional carbon-based conductive polymer nanosheet array composite material, comprising the following steps:

[0015] Disperse the two-dimensional carbon-based material in an aqueous hydrochloric acid solution with a concentration of 0.1-0.5 wt.%, to form a uniform suspension;

[0016] Add potassium permanganate to the suspension, and carry out a hydrothermal reaction with the two-dimensional carbon-based material at 120-160 °C for 4-8 hours to generate a carbon-based composite material with a cross two-dimensional manganese dioxide nanosheet structure loaded on the surface;

[0017] Centrifuge, wash and dry to obtain a two-dimensional manganese dioxide-carbon-based composite material;

[0018] Disperse the above two-dimensional manganese dioxide-carbon-based composite material in an aqueous hydrochloric acid solution with a concentration of 0.3-1.8 wt.%, add a conductive polymer monomer, and react at 25-60 °C for 2-8 hours to cause the manganese dioxide to induce the oxidative polymerization reaction of the monomer;

[0019] Centrifuge, wash and dry to obtain the two-dimensional carbon-based conductive polymer nanosheet array composite material.

[0020] Preferably, a method for preparing a two-dimensional carbon-based conductive polymer nanosheet array composite material, comprising the following steps:

[0021] Step A: Disperse the two-dimensional carbon-based material into an aqueous hydrochloric acid solution, mix evenly, and stir at room temperature for 10-30 min to prepare a suspension containing the two-dimensional carbon-based material;

[0022] Step B: Add potassium permanganate to the suspension containing the two-dimensional carbon-based material, stir at room temperature for 10-30 min to prepare a mixed solution, and place it at 120-160 °C for reaction for 4-8 h to obtain product X;

[0023] Step C: Centrifuge the product X, wash it with deionized water, and then dry it under vacuum at 35 - 55 °C to obtain the two-dimensional manganese dioxide carbon-based composite material;

[0024] Step D: Disperse the two-dimensional manganese dioxide carbon-based composite material into an aqueous hydrochloric acid solution to prepare a dispersion containing the two-dimensional manganese dioxide carbon-based composite material;

[0025] Step E: Add the conductive polymer monomer to the dispersion containing the two-dimensional manganese dioxide carbon-based composite material, and carry out the reaction at 25 - 60 °C for 2 - 8 h to obtain product Y;

[0026] Step F: Centrifuge the product Y, wash it with deionized water, and then dry it under vacuum at 35 - 55 °C to obtain the two-dimensional carbon-based conductive polymer nanosheet array composite material.

[0027] Further preferably, in step A, the two-dimensional carbon-based material is one or more of graphene oxide, reduced graphene oxide, Ti3C2T x MXene, Ti2CT x MXene, Ti3CN MXene, Nb4C3T x MXene, Nb2CT x MXene; the concentration of the aqueous hydrochloric acid solution is 0.15 - 0.37 wt.%; the mass ratio of the two-dimensional carbon-based material to the aqueous hydrochloric acid solution is 1:(1 - 5).

[0028] Further preferably, in step B, the mass ratio of potassium permanganate to the two-dimensional carbon-based material is (0.05 - 0.1):1.

[0029] Further preferably, in step D, the concentration of the aqueous hydrochloric acid solution is 0.3 - 1.8 wt.%; the mass ratio of the two-dimensional manganese dioxide carbon-based composite material to the aqueous hydrochloric acid solution is 1:(100 - 250).

[0030] Further preferably, in step E, the mass ratio of the conductive polymer monomer to the dispersion containing the two-dimensional manganese dioxide carbon-based composite material is 1:(200 - 600); the conductive polymer monomer is one or more of pyrrole, aniline, indole, and p-phenylenediamine. More preferably, the conductive polymer monomer is a mixture of pyrrole and indole. More preferably, the mass ratio of pyrrole to indole is 1:(0.2 - 5); most preferably, the mass ratio of pyrrole to indole is 1:(0.5 - 2).

[0031] Further preferably, step E can also be: adding a conductive polymer monomer and phenylguanidine (CAS No.: 2002-16-6) into the dispersion liquid containing the two-dimensional manganese dioxide carbon-based composite material, reacting at 25-60 °C for 2-8 h to obtain product Y. The mass ratio of the conductive polymer monomer to phenylguanidine is 1:(0.05-0.15). Phenylguanidine stabilizes free radicals and promotes polymerization, and the benzene ring enhances the π-π interaction of the template, synergistically improving the array order and response performance.

[0032] The present invention also discloses a two-dimensional carbon-based conductive polymer nanosheet array composite material, which is prepared by the above method.

[0033] The present invention also discloses an application of the two-dimensional carbon-based conductive polymer nanosheet array composite material in an organic gas sensor.

[0034] In the present invention, two-dimensional cross-array-shaped MnO2 nanosheets are in-situ constructed on the surface of the two-dimensional carbon-based material through a hydrothermal reaction. MnO2 serves as both an oxidation initiator and a structure-directing template for the conductive polymer monomer in the subsequent oxidative polymerization, realizing the in-situ array growth of the conductive polymer on its surface. This structure can accurately replicate the two-dimensional sheet morphology of MnO2, significantly improving the structural controllability and purity of the composite material.

[0035] Doping is synchronously achieved during the polymerization process under acidic conditions, improving the intrinsic conductivity of the conductive polymer. The prepared composite material has a high specific surface area, excellent interfacial electron transport ability and molecular recognition ability, showing significantly improved response performance and long-term stability in gas sensing tests, and having comprehensive advantages such as simple process, easy availability of raw materials, and suitability for large-scale production, and is applicable to the fields of high-performance sensors and other nano-functional devices. Description of the Drawings

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for description in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain other drawings based on these drawings without creative efforts.

[0037] Figure 1 Scanning electron microscope image of the polypyrrole nanosheet array / Ti3C2T x MXene composite material provided in Embodiment 1 of the present invention;

[0038] Figure 2 Scanning electron microscope image of the polyaniline nanosheet array / Ti3C2T x MXene composite material provided in Embodiment 2 of the present invention;

[0039] Figure 3 Scanning electron microscope image of the polypyrrole nanosheet array / graphene oxide composite provided in Embodiment 3 of the present invention;

[0040] Figure 4 Scanning electron microscope image of the pyrrole-indole copolymer nanosheet array / graphene oxide composite provided in Embodiment 4 of the present invention;

[0041] Figure 5 Scanning electron microscope image of the polyindole nanosheet array / graphene oxide composite provided in Embodiment 5 of the present invention;

[0042] Figure 6 Scanning electron microscope image of the polyaniline nanosheet array / graphene oxide composite provided in Embodiment 6 of the present invention;

[0043] Figure 7 Concentration response curve of the polypyrrole nanosheet array / graphene oxide composite provided in Embodiment 3 of the present invention to dibutyl phthalate;

[0044] Figure 8 Concentration response curve of the pyrrole-indole copolymer nanosheet array / graphene oxide composite provided in Embodiment 4 of the present invention to dibutyl phthalate. Detailed implementation manners

[0045] The technical problems, technical solutions and advantages of the present invention will be elaborated in detail below by referring to exemplary embodiments. The following exemplary embodiments are only used to explain the present invention and should not be construed as limiting the present invention. Those skilled in the art of the present technology can understand that unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of those of ordinary skill in the art in the field to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted in an idealized or overly formal sense unless defined herein.

[0046] A preparation method of a two-dimensional carbon-based conductive polymer nanosheet array composite material includes the following steps:

[0047] Step A: Disperse the two-dimensional carbon-based material into an aqueous hydrochloric acid solution, mix evenly, and stir at room temperature for 10 - 30 min to obtain a suspension containing the two-dimensional carbon-based material; the two-dimensional carbon-based material is graphene oxide, reduced graphene oxide, Ti3C2T x MXene, Ti2CT x MXene, Ti3CN MXene, Nb4C3T x MXene, Nb2CT xOne or more of MXene; the concentration of the aqueous hydrochloric acid solution is 0.15 - 0.37 wt.%; the mass ratio of the two-dimensional carbon-based material to the aqueous hydrochloric acid solution is 1:(1 - 5); the main function of this step is to obtain a stable reaction solution, so as to provide a uniform next product in the subsequent chemical reaction.

[0048] Step B: Add potassium permanganate to the suspension containing the two-dimensional carbon-based material, stir at room temperature for 10 - 30 min to obtain a mixed solution, and react at 120 - 160 °C for 4 - 8 h to obtain a product; the mass ratio of potassium permanganate to the two-dimensional carbon-based material is (0.05 - 0.1):1; the purpose of this step is to generate a two-dimensional manganese dioxide-carbon-based composite material through the reaction, and the adjustment of the reaction temperature and time can directly affect the growth of the manganese dioxide two-dimensional nanosheet array.

[0049] Step C: Centrifuge the product, wash it with deionized water, and then dry it in vacuum at 35 - 55 °C to obtain a two-dimensional manganese dioxide-carbon-based composite material; in this step, the product generated after the reaction in Step B is separated by centrifugation to remove the reaction residual liquid. Subsequently, the separated product is washed with deionized water to remove the impurities remaining on the surface. Then, the washed product is dried in a vacuum environment to finally obtain a pure two-dimensional manganese dioxide-carbon-based composite material.

[0050] Step D: Disperse the two-dimensional manganese dioxide-carbon-based composite material into an aqueous hydrochloric acid solution with a concentration of 0.3 - 1.8 wt.% to obtain a dispersion containing the two-dimensional manganese dioxide-carbon-based composite material; the mass ratio of the two-dimensional manganese dioxide-carbon-based composite material to the aqueous hydrochloric acid solution is 1:(100 - 250); the main function of this step is to ensure the uniform dispersion of the two-dimensional manganese dioxide-carbon-based composite material in the acidic solvent, so as to provide a stable reaction environment for the subsequent polymerization reaction.

[0051] Step E: Add a conductive polymer monomer to the dispersion containing the two-dimensional manganese dioxide carbon-based composite material to prepare a reaction solution. Place the reaction solution at 25 - 60 °C for reaction for 2 - 8 h to obtain a two-dimensional carbon-based conductive polymer nanosheet array composite material; the mass ratio of the conductive polymer monomer to the dispersion containing the two-dimensional manganese dioxide carbon-based composite material is 1:(200 - 600); the conductive polymer monomer is one or more of pyrrole, aniline, indole, and p-phenylenediamine. Under the guidance of the two-dimensional MnO2 cross-array template used in the present invention, the electronic structure and polymerization behavior of the conductive polymer monomer will directly affect its ability to replicate the template structure, and thus determine the array regularity and gas-sensing response performance of the composite material. Research has found that the pyrrole and indole copolymerization system exhibits good electronic synergistic characteristics in this template structure: pyrrole molecules have a high charge density and strong polymerization activity, which can provide an efficient conductive skeleton; indole molecules have a large conjugated area and strong π-π stacking ability, which helps to enhance surface adsorption on the template and two-dimensional expansion. The copolymerization of the two can achieve the synergistic matching of free radical initiation efficiency and molecular stacking ability, and it is easier to replicate the nanosheet array structure under the guidance of MnO2 to construct a conductive network with a high specific surface area and high regularity, thereby significantly improving the gas response performance. In contrast, aniline molecules are difficult to effectively participate in free radical-induced polymerization reactions due to their stable resonance structure and high oxidation polymerization potential. At the same time, their rigid molecular structure and limited π stacking ability make it impossible to form a regular structure by co-assembling with pyrrole or indole. Under the guidance of the MnO2 template, aniline-related copolymerization systems often exhibit monomer dispersion polymerization, interface fracture, or array replication failure, forming a dense or disordered structure, resulting in a decrease rather than an increase in the response performance.

[0052] Step F: Centrifuge the product and wash it with deionized water, and then dry it in vacuum at 35 - 55 °C to obtain a two-dimensional carbon-based conductive polymer nanosheet array composite material. In this step, the product generated after the reaction in Step E is subjected to solid-liquid separation by centrifugation to remove the reaction residue. Subsequently, the separated product is washed with deionized water to remove the impurities remaining on the surface. Then, the washed product is placed in a vacuum environment for drying to finally obtain a pure two-dimensional carbon-based conductive polymer nanosheet array composite material. The obtained two-dimensional carbon-based conductive polymer nanosheet array composite material has the characteristics of a two-dimensional structure. The polymer nanosheets grow crosswise on the surface of the two-dimensional carbon-based material to form an array containing a porous structure, which significantly improves the specific surface area and practicality of the material, exposes more active sites, facilitates the adsorption and desorption of guest molecules, and enables it to exhibit better performance in applications.

[0053] The present invention provides a new method for preparing a two-dimensional carbon-based conductive polymer nanosheet array composite material. Using a two-dimensional carbon-based material as a substrate, manganese dioxide is induced to grow on its surface during the hydrothermal reaction process to form two-dimensional cross nanosheets. The obtained two-dimensional manganese dioxide-carbon-based composite material is used as an oxidant to initiate the polymerization of monomers, and a two-dimensional carbon-based conductive polymer nanosheet array composite material is prepared. Specifically, first, the two-dimensional carbon-based material is dispersed in an aqueous hydrochloric acid solution to form a stable solution environment. Subsequently, potassium permanganate is added to the solution to ensure its complete dissolution and form a uniform reaction solution. In the reaction stage, potassium permanganate will adsorb on the surface of the two-dimensional carbon-based material and gradually decompose to generate manganese dioxide crystals. By controlling the reaction temperature and time, the generated manganese dioxide crystals aggregate and crystallize along a specific direction due to surface energy, and finally, manganese dioxide cross nanosheets are formed on the surface of the two-dimensional carbon-based material. Subsequently, centrifugal separation and deionized water washing are used to remove the reaction residues, and then vacuum drying is carried out to obtain a two-dimensional manganese dioxide-carbon-based composite material. After dispersing the obtained two-dimensional manganese dioxide-carbon-based composite material in an aqueous hydrochloric acid solution to form a stable solution environment, a conductive polymer monomer is added and completely dissolved to form a uniform reaction solution. In the subsequent polymerization reaction stage, due to the strong oxidizing property of manganese dioxide, it can act as an oxidant for the polymerization of conductive polymer monomers. Monomer molecules adsorb on the manganese dioxide interface and are oxidized and polymerized, while manganese dioxide is reduced to generate manganese ions soluble in water and is continuously etched and removed. Therefore, the conductive polymer generated on the surface of the two-dimensional carbon-based material can completely replicate the two-dimensional nanosheet structure of manganese dioxide, thereby generating a two-dimensional carbon-based conductive polymer nanosheet array composite material. The preparation method of the present invention is simple and efficient, and the obtained two-dimensional carbon-based conductive polymer nanosheet array composite material has excellent two-dimensional structure and nanocomposite properties.

[0054] Graphene oxide, catalog number: G139803, purchased from Aladdin;

[0055] Ti3C2T x MXene, catalog number: T463267, purchased from Aladdin;

[0056] Example 1:

[0057] A preparation method of a polypyrrole nanosheet array / Ti3C2T x MXene composite material, comprising the following steps:

[0058] Step A: Add 20 mg of Ti3C2T x Mxene to 60 mL of 0.25 wt.% aqueous hydrochloric acid solution, stir at room temperature for 20 min, and prepare a suspension containing Ti3C2T x Mxene.

[0059] Step B: Add 400 mg of potassium permanganate to the above-mentioned suspension containing Ti3C2T x MXene, stir for 10 min to obtain a mixed solution, transfer it to a hydrothermal reactor, and place it at 150 °C for reaction for 4 h to obtain a product;

[0060] Step C: Centrifuge the product, wash it with deionized water, and then dry it in vacuum at 40 °C to obtain a two-dimensional manganese dioxide / Ti3C2T x MXene composite material;

[0061] Step D: Add 100 mg of the two-dimensional manganese dioxide / Ti3C2T x MXene composite material obtained in Step C to 20 mL of 0.4 wt.% hydrochloric acid aqueous solution to prepare a dispersion containing the two-dimensional manganese dioxide / Ti3C2T x MXene composite material.

[0062] Step E: Add 50 mg of pyrrole monomer to the above-mentioned dispersion containing the two-dimensional manganese dioxide / Ti3C2T x MXene composite material to prepare a reaction solution; and stir the above reaction solution at 25 °C for oxidative polymerization reaction for 2 h.

[0063] Step F: Centrifuge the product obtained in Step E, wash it with deionized water, and then dry it in vacuum at 35 °C to obtain a polypyrrole nanosheet array / Ti3C2T x MXene composite material.

[0064] See Figure 1 , the obtained polypyrrole nanosheet array / Ti3C2T x MXene composite material has a two-dimensional structure, and polypyrrole nanosheets cross on the surface of Ti3C2T x MXene to form an array and channels.

[0065] Example 2:

[0066] A preparation method of a polyaniline nanosheet array / Ti3C2T x MXene composite material, comprising the following steps:

[0067] Step A: Add 20 mg of Ti3C2T x MXene to 60 mL of 0.25 wt.% hydrochloric acid aqueous solution, stir at room temperature for 20 min to obtain a suspension containing Ti3C2T x MXene.

[0068] Step B: Add 400 mg of potassium permanganate to the above-mentioned suspension containing Ti3C2T xIn the suspension of Mxene, stir for 10 min to obtain a mixed solution, transfer it to a hydrothermal reactor, and react at 150 °C for 4 h to obtain a product;

[0069] Step C: Centrifuge the product, wash it with deionized water, and then dry it in vacuum at 40 °C to obtain two-dimensional manganese dioxide / Ti3C2T x Mxene composite.

[0070] Step D: Add 100 mg of the two-dimensional manganese dioxide / Ti3C2T x Mxene composite to 20 mL of 0.4 wt.% hydrochloric acid aqueous solution to prepare a dispersion containing the two-dimensional manganese dioxide / Ti3C2T x Mxene composite.

[0071] Step E: Add 50 mg of aniline monomer to the above dispersion containing the two-dimensional manganese dioxide / Ti3C2T x Mxene composite to prepare a reaction solution; and stir the above reaction solution at 25 °C for 2 h for oxidative polymerization reaction.

[0072] Step F: Centrifuge the product obtained from the reaction in Step E, wash it with deionized water, and then dry it in vacuum at 35 °C to obtain polypyrrole nanosheet array / Ti3C2T x MXene composite.

[0073] See Figure 2 , the obtained polyaniline nanosheet array / Ti3C2T x MXene composite has a two-dimensional structure, and polyaniline nanosheets cross on the surface of Ti3C2T x Mxene to form arrays and channels.

[0074] Example 3:

[0075] A method for preparing a polypyrrole nanosheet array / graphene oxide composite, comprising the following steps:

[0076] Step A: Add 20 mg of graphene oxide to 60 mL of 0.25 wt.% hydrochloric acid aqueous solution, and stir at room temperature for 20 min to obtain a suspension containing graphene oxide.

[0077] Step B: Add 400 mg of potassium permanganate to the above suspension containing graphene oxide material, stir for 10 min to obtain a mixed solution, transfer it to a hydrothermal reactor, and react at 150 °C for 4 h to obtain a product;

[0078] Step C: Centrifuge the product, wash it with deionized water, and then dry it under vacuum at 40 °C to obtain a two-dimensional manganese dioxide / graphene oxide composite material.

[0079] Step D: Add 100 mg of the two-dimensional manganese dioxide / graphene oxide composite material obtained in Step C to 20 mL of a 0.4 wt.% hydrochloric acid aqueous solution to prepare a dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material.

[0080] Step E: Add 50 mg of pyrrole monomer to the above dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material to prepare a reaction solution; and place the above reaction solution under stirring at 25 °C for an oxidative polymerization reaction for 2 h.

[0081] Step F: Centrifuge the product obtained from the reaction in Step E, wash it with deionized water, and then dry it under vacuum at 35 °C to obtain a polypyrrole nanosheet array / graphene oxide composite material.

[0082] See Figure 3 , the obtained polypyrrole nanosheet array / graphene oxide composite material has a two-dimensional structure, and the polypyrrole nanosheets cross on the surface of graphene oxide to form an array and channels.

[0083] Example 4:

[0084] A preparation method of a pyrrole-indole copolymer nanosheet array / graphene oxide composite material, comprising the following steps:

[0085] Step A: Add 20 mg of graphene oxide to 60 mL of a 0.25 wt.% hydrochloric acid aqueous solution, stir at room temperature for 20 min to prepare a suspension containing graphene oxide.

[0086] Step B: Add 400 mg of potassium permanganate to the above suspension containing the graphene oxide material, stir for 10 min to prepare a mixed solution, and transfer it to a hydrothermal autoclave, place it at 150 °C for reaction for 4 h to obtain a product;

[0087] Step C: Centrifuge the product, wash it with deionized water, and then dry it under vacuum at 40 °C to obtain a two-dimensional manganese dioxide / graphene oxide composite material.

[0088] Step D: Add 100 mg of the two-dimensional manganese dioxide / graphene oxide composite material obtained in Step C to 20 mL of a 0.4 wt.% hydrochloric acid aqueous solution to prepare a dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material.

[0089] Step E: Add 25 mg of pyrrole and 25 mg of indole monomer into the above-mentioned dispersion liquid containing the two-dimensional manganese dioxide / graphene oxide composite material to prepare a reaction solution; and place the above-mentioned reaction solution under stirring at 25 °C for an oxidative polymerization reaction for 2 h.

[0090] Step F: Centrifuge the product obtained from the reaction in Step E, wash it with deionized water, and then dry it in vacuum at 35 °C to obtain a pyrrole-indole copolymer nanosheet array / graphene oxide composite material.

[0091] See Figure 4 , the obtained pyrrole-indole copolymer nanosheet array / graphene oxide composite material has a two-dimensional structure, and the pyrrole-indole copolymer nanosheets cross-form an array and channels on the surface of graphene oxide.

[0092] Example 5:

[0093] A preparation method of a polyindole nanosheet array / graphene oxide composite material, comprising the following steps:

[0094] Step A: Add 20 mg of graphene oxide into 60 mL of 0.25 wt.% hydrochloric acid aqueous solution, stir at room temperature for 20 min to prepare a suspension containing graphene oxide.

[0095] Step B: Add 400 mg of potassium permanganate into the above-mentioned suspension containing the graphene oxide material, stir for 10 min to obtain a mixed solution, transfer it to a hydrothermal reactor, and react at 150 °C for 4 h to obtain a product;

[0096] Step C: Centrifuge the product, wash it with deionized water, and then dry it in vacuum at 40 °C to obtain a two-dimensional manganese dioxide / graphene oxide composite material.

[0097] Step D: Add 100 mg of the two-dimensional manganese dioxide / graphene oxide composite material obtained in Step C into 20 mL of 0.4 wt.% hydrochloric acid aqueous solution to prepare a dispersion liquid containing the two-dimensional manganese dioxide / graphene oxide composite material.

[0098] Step E: Add 50 mg of indole monomer into the above-mentioned dispersion liquid containing the two-dimensional manganese dioxide / graphene oxide composite material to prepare a reaction solution; and place the above-mentioned reaction solution under stirring at 25 °C for an oxidative polymerization reaction for 2 h.

[0099] Step F: Centrifuge the product obtained from the reaction in Step E, wash it with deionized water, and then dry it in vacuum at 35 °C to obtain a polyindole nanosheet array / graphene oxide composite material.

[0100] See Figure 5, the obtained polyindole nanosheet array / graphene oxide composite material has a two-dimensional structure, and the polyindole nanosheets cross on the surface of graphene oxide to form an array and channels.

[0101] Example 6:

[0102] A preparation method of a polyaniline nanosheet array / graphene oxide composite material includes the following steps:

[0103] Step A: Add 20 mg of graphene oxide to 60 mL of 0.25 wt.% hydrochloric acid aqueous solution, stir at room temperature for 20 min to obtain a suspension containing graphene oxide.

[0104] Step B: Add 400 mg of potassium permanganate to the above suspension containing graphene oxide material, stir for 10 min to obtain a mixed solution, transfer it to a hydrothermal reactor, and react at 150 °C for 4 h to obtain a product;

[0105] Step C: Centrifuge the product, wash it with deionized water, and then dry it in vacuum at 40 °C to obtain a two-dimensional manganese dioxide / graphene oxide composite material.

[0106] Step D: Add 100 mg of the two-dimensional manganese dioxide / graphene oxide composite material obtained in Step C to 20 mL of 0.4 wt.% hydrochloric acid aqueous solution to obtain a dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material.

[0107] Step E: Add 50 mg of aniline monomer to the above dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material to prepare a reaction solution; and place the above reaction solution under stirring at 25 °C for an oxidative polymerization reaction for 2 h.

[0108] Step F: Centrifuge the product obtained from the reaction in Step E, wash it with deionized water, and then dry it in vacuum at 35 °C to obtain a polyaniline nanosheet array / graphene oxide composite material.

[0109] See Figure 6 , the obtained polyaniline nanosheet array / graphene oxide composite material has a two-dimensional structure, and the polyaniline nanosheets cross on the surface of graphene oxide to form an array and channels.

[0110] Example 7:

[0111] A preparation method of an aniline-pyrrole copolymer nanosheet array / graphene oxide composite material includes the following steps:

[0112] Step A: Add 20 mg of graphene oxide to 60 mL of 0.25 wt.% hydrochloric acid aqueous solution, stir at room temperature for 20 min to obtain a suspension containing graphene oxide.

[0113] Step B: Add 400 mg of potassium permanganate into the above suspension containing graphene oxide material, stir for 10 min to obtain a mixed solution, transfer it to a hydrothermal reactor, and react at 150 °C for 4 h to obtain a product;

[0114] Step C: Centrifuge the product, wash it with deionized water, and then dry it in vacuum at 40 °C to obtain a two-dimensional manganese dioxide / graphene oxide composite material.

[0115] Step D: Add 100 mg of the two-dimensional manganese dioxide / graphene oxide composite material obtained in Step C into 20 mL of 0.4 wt.% hydrochloric acid aqueous solution to prepare a dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material.

[0116] Step E: Add 25 mg of aniline and 25 mg of pyrrole monomer into the above dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material to prepare a reaction solution; and stir the above reaction solution at 25 °C for 2 h for an oxidative polymerization reaction.

[0117] Step F: Centrifuge the product obtained from the reaction in Step E, wash it with deionized water, and then dry it in vacuum at 35 °C to obtain an aniline-pyrrole copolymer nanosheet array / graphene oxide composite material.

[0118] Example 8:

[0119] A preparation method of an aniline-indole copolymer nanosheet array / graphene oxide composite material, comprising the following steps:

[0120] Step A: Add 20 mg of graphene oxide into 60 mL of 0.25 wt.% hydrochloric acid aqueous solution, stir at room temperature for 20 min to obtain a suspension containing graphene oxide.

[0121] Step B: Add 400 mg of potassium permanganate into the above suspension containing graphene oxide material, stir for 10 min to obtain a mixed solution, transfer it to a hydrothermal reactor, and react at 150 °C for 4 h to obtain a product;

[0122] Step C: Centrifuge the product, wash it with deionized water, and then dry it in vacuum at 40 °C to obtain a two-dimensional manganese dioxide / graphene oxide composite material.

[0123] Step D: Add 100 mg of the two-dimensional manganese dioxide / graphene oxide composite material obtained in Step C into 20 mL of 0.4 wt.% hydrochloric acid aqueous solution to prepare a dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material.

[0124] Step E: Add 25 mg of aniline and 25 mg of indole monomer into the above-mentioned dispersion liquid containing the two-dimensional manganese dioxide / graphene oxide composite material to prepare a reaction solution; and place the above reaction solution under stirring at 25 °C for an oxidative polymerization reaction for 2 h.

[0125] Step F: Centrifuge the product obtained from the reaction in Step E, wash it with deionized water, and then dry it in vacuum at 35 °C to obtain an aniline-indole copolymer nanosheet array / graphene oxide composite material.

[0126] Example 9:

[0127] A preparation method of a pyrrole-indole copolymer nanosheet array / graphene oxide composite material, comprising the following steps:

[0128] Step A: Add 20 mg of graphene oxide into 60 mL of 0.25 wt.% hydrochloric acid aqueous solution, and stir at room temperature for 20 min to prepare a suspension containing graphene oxide.

[0129] Step B: Add 400 mg of potassium permanganate into the above-mentioned hydrochloric acid aqueous solution containing the graphene oxide material, stir for 10 min to prepare a mixed solution, transfer it to a hydrothermal reactor, and place it at 150 °C for reaction for 4 h to obtain a product;

[0130] Step C: Centrifuge the product, wash it with deionized water, and then dry it in vacuum at 40 °C to obtain a two-dimensional manganese dioxide / graphene oxide composite material.

[0131] Step D: Add 100 mg of the two-dimensional manganese dioxide / graphene oxide composite material obtained in Step C into 20 mL of 0.4 wt.% hydrochloric acid aqueous solution to prepare a dispersion liquid containing the two-dimensional manganese dioxide / graphene oxide composite material.

[0132] Step E: Add 25 mg of pyrrole, 25 mg of indole monomer, and 5 mg of phenylguanidine into the above-mentioned dispersion liquid containing the two-dimensional manganese dioxide / graphene oxide composite material to prepare a reaction solution; and place the above reaction solution under stirring at 25 °C for an oxidative polymerization reaction for 2 h.

[0133] Step F: Centrifuge the product obtained from the reaction in Step E, wash it with deionized water, and then dry it in vacuum at 35 °C to obtain a pyrrole-indole copolymer nanosheet array / graphene oxide composite material.

[0134] Example 10:

[0135] A preparation method of a pyrrole-indole copolymer nanosheet array / graphene oxide composite material, comprising the following steps:

[0136] Step A: Add 20 mg of graphene oxide to 60 mL of 0.25 wt.% hydrochloric acid aqueous solution, stir at room temperature for 20 min to obtain a suspension containing graphene oxide.

[0137] Step B: Add 400 mg of potassium permanganate to the above-mentioned hydrochloric acid aqueous solution containing graphene oxide material, stir for 10 min to obtain a mixed solution, transfer it to a hydrothermal reactor, and react at 150 °C for 4 h to obtain a product;

[0138] Step C: Centrifuge the product, wash it with deionized water, and then dry it in vacuum at 40 °C to obtain a two-dimensional manganese dioxide / graphene oxide composite material.

[0139] Step D: Add 100 mg of the two-dimensional manganese dioxide / graphene oxide composite material obtained in Step C to 20 mL of 0.4 wt.% hydrochloric acid aqueous solution to obtain a dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material.

[0140] Step E: Add 25 mg of pyrrole and 25 mg of indole monomers, 5 mg of phenylguanidine, and 1 mg of phytic acid to the above-mentioned dispersion containing the two-dimensional manganese dioxide / graphene oxide composite material to prepare a reaction solution; and place the above reaction solution under stirring at 25 °C for an oxidative polymerization reaction for 2 h. In particular, phytic acid is used as a cross-linking agent, and a conductive polymer is added to the two-dimensional manganese dioxide carbon-based composite material to form a porous structure, which not only provides a large specific surface area but also improves electron transport.

[0141] Step F: Centrifuge the product obtained from the reaction in Step E, wash it with deionized water, and then dry it in vacuum at 35 °C to obtain a pyrrole-indole copolymer nanosheet array / graphene oxide composite material.

[0142] Application Example 1:

[0143] This application example provides the test results of the polypyrrole nanosheet array / Ti3C2T x MXene composite material for detecting the concentration of dibutyl phthalate at 35 °C.

[0144] The specific test method includes the following steps:

[0145] Step A: Disperse the polypyrrole nanosheet array / Ti3C2T x MXene composite material prepared in Example 1 in absolute ethanol and grind it into a slurry state. The mass ratio of the polypyrrole nanosheet array / Ti3C2T x MXene composite material to absolute ethanol is 1:10;

[0146] Step B: Uniformly coat 1 μL of the slurry material on the substrate of the MEMS test element (1×1 mm2 ) and air-dry;

[0147] Step C, heat the test element coated with polypyrrole nanosheet array / Ti3C2T x MXene composite material to 50 °C and age for 48 h;

[0148] Step D, place the test element coated with polypyrrole nanosheet array / Ti3C2T x MXene composite material in the Narui MA1.0 gas-sensing test system, adjust the temperature to 35 °C, inject a dibutyl phthalate concentration of 300 ppb and record the response value;

[0149] The material of Example 1 has a response value of 35.5% to 300 ppb of dibutyl phthalate.

[0150] Application Example 2:

[0151] This application example provides the test results of the polyaniline nanosheet array / Ti3C2T x MXene composite material of the present invention for detecting the concentration of dibutyl phthalate at 35 °C.

[0152] The specific test method includes the following steps:

[0153] Step A, disperse the polyaniline nanosheet array / Ti3C2T x MXene composite material prepared in Example 2 in absolute ethanol and grind it into a slurry. The mass ratio of the polyaniline nanosheet array / Ti3C2T x MXene composite material to absolute ethanol is 1:10;

[0154] Step B, uniformly coat 1 μL of the slurry material on the substrate (1×1 mm 2 ) of the MEMS test element and air-dry;

[0155] Step C, heat the test element coated with polyaniline nanosheet array / Ti3C2T x MXene composite material to 50 °C and age for 48 h;

[0156] Step D, place the test element coated with polyaniline nanosheet array / Ti3C2T x MXene composite material in the Narui MA1.0 gas-sensing test system, adjust the temperature to 35 °C, inject a dibutyl phthalate concentration of 300 ppb and record the response value;

[0157] The material of Example 2 has a response value of 16.7% to 300 ppb of dibutyl phthalate.

[0158] Application Example 3:

[0159] This application example provides the test results of the polypyrrole nanosheet array / graphene oxide composite material of the present invention for detecting the concentration of dibutyl phthalate at 35°C.

[0160] The specific test method includes the following steps:

[0161] Step A: Disperse the polypyrrole nanosheet array / graphene oxide composite material prepared in Example 3 in absolute ethanol and grind it into a paste. The mass ratio of the polypyrrole nanosheet array / graphene oxide composite material to absolute ethanol is 1:10;

[0162] Step B: Uniformly coat 1 μL of the paste-like material on the substrate (1×1 mm 2 ) of the MEMS test element and let it dry;

[0163] Step C: Heat the test element coated with the polypyrrole nanosheet array / graphene oxide composite material to 50°C and age it for 48 h;

[0164] Step D: Place the test element coated with the polypyrrole nanosheet array / graphene oxide composite material in the Narui MA1.0 gas-sensing test system, adjust the temperature to 35°C, inject a dibutyl phthalate concentration of 300 ppb, and record the response value;

[0165] As Figure 7 shown, the material of Example 3 has a response value of 31.3% to 300 ppb of dibutyl phthalate.

[0166] Application Example 4:

[0167] This application example provides the test results of the pyrrole-indole copolymer nanosheet array / graphene oxide composite material of the present invention for detecting the concentration of dibutyl phthalate at 35°C.

[0168] The specific test method includes the following steps:

[0169] Step A: Disperse the pyrrole-indole copolymer nanosheet array / graphene oxide composite material prepared in Example 4 in absolute ethanol and grind it into a paste. The mass ratio of the pyrrole-indole copolymer nanosheet array / graphene oxide composite material to absolute ethanol is 1:10;

[0170] Step B: Uniformly coat 1 μL of the paste-like material on the substrate (1×1 mm 2 ) of the MEMS test element and let it dry;

[0171] Step C: Heat the test element coated with the pyrrole-indole copolymer nanosheet array / graphene oxide composite to 50 °C and age it for 48 h;

[0172] Step D: Place the test element coated with the pyrrole-indole copolymer nanosheet array / graphene oxide composite in the Narui MA1.0 gas sensor test system, adjust the temperature to 35 °C, inject 300 ppb of dibutyl phthalate, and record the response value;

[0173] As Figure 8 shown, the response value of the material in Example 4 to 300 ppb of dibutyl phthalate is 106.2%.

[0174] Application Example 5:

[0175] This application example provides the test results of the polyindole nanosheet array / graphene oxide composite of the present invention for detecting the concentration of dibutyl phthalate at 35 °C.

[0176] The specific test method includes the following steps:

[0177] Step A: Disperse the polyindole nanosheet array / graphene oxide composite prepared in Example 5 in absolute ethanol and grind it into a slurry. The mass ratio of the polyindole nanosheet array / graphene oxide composite to absolute ethanol is 1:10;

[0178] Step B: Uniformly coat 1 μL of the slurry-like material on the substrate (1×1 mm 2 ) of the MEMS test element and let it dry;

[0179] Step C: Heat the test element coated with the polyindole nanosheet array / graphene oxide to 50 °C and age it for 48 h;

[0180] Step D: Place the test element coated with the polyindole nanosheet array / graphene oxide composite in the Narui MA1.0 gas sensor test system, adjust the temperature to 35 °C, inject 300 ppb of dibutyl phthalate concentration, and record the response value;

[0181] The material in Example 5 has a response value of 37.1% to 300 ppb of dibutyl phthalate.

[0182] Application Example 6:

[0183] This application example provides the test results of the polyaniline nanosheet array / graphene oxide composite of the present invention for detecting the concentration of dibutyl phthalate at 35 °C.

[0184] The specific test method includes the following steps:

[0185] Step A: Disperse the polyaniline nanosheet array / graphene oxide composite material prepared in Example 6 in absolute ethanol and grind it into a slurry. The mass ratio of the polyaniline nanosheet array / graphene oxide composite material to absolute ethanol is 1:10;

[0186] Step B: Uniformly coat 1 μL of the slurry material on the substrate (1×1 mm 2 ) of the MEMS test element and let it dry;

[0187] Step C: Heat the test element coated with the polyaniline nanosheet array / graphene oxide to 50 °C and age it for 48 h;

[0188] Step D: Place the test element coated with the polyaniline nanosheet array / graphene oxide composite material in the Narui MA1.0 gas-sensing test system, adjust the temperature to 35 °C, inject a dibutyl phthalate concentration of 300 ppb and record the response value;

[0189] The material of Example 6 has a response value of 26.8% to 300 ppb of dibutyl phthalate.

[0190] Application Example 7:

[0191] This application example provides the test results of the aniline-pyrrole copolymer nanosheet array / graphene oxide composite material of the present invention for detecting the concentration of dibutyl phthalate at 35 °C.

[0192] The specific test method includes the following steps:

[0193] Step A: Disperse the aniline-pyrrole copolymer nanosheet array / graphene oxide composite material prepared in Example 7 in absolute ethanol and grind it into a slurry. The mass ratio of the aniline-pyrrole copolymer nanosheet array / graphene oxide composite material to absolute ethanol is 1:10;

[0194] Step B: Uniformly coat 1 μL of the slurry material on the substrate (1×1 mm 2 ) of the MEMS test element and let it dry;

[0195] Step C: Heat the test element coated with the aniline-pyrrole copolymer nanosheet array / graphene oxide to 50 °C and age it for 48 h;

[0196] Step D: Place the test element coated with the aniline-pyrrole copolymer nanosheet array / graphene oxide composite material in the Narui MA1.0 gas-sensing test system, adjust the temperature to 35 °C, inject a dibutyl phthalate concentration of 300 ppb and record the response value;

[0197] The material of Example 7 has a response value of 28.9% to 300 ppb of dibutyl phthalate.

[0198] Application Example 8:

[0199] This application example provides the test results of the aniline - indole copolymer nanosheet array / graphene oxide composite material of the present invention for detecting the concentration of dibutyl phthalate at 35°C.

[0200] The specific test method includes the following steps:

[0201] Step A: Disperse the aniline - indole copolymer nanosheet array / graphene oxide composite material prepared in Example 8 in absolute ethanol and grind it into a slurry. The mass ratio of the aniline - indole copolymer nanosheet array / graphene oxide composite material to absolute ethanol is 1:10;

[0202] Step B: Uniformly coat 1 μL of the slurry - like material on the substrate (1×1 mm 2 ) of the MEMS test element and let it dry;

[0203] Step C: Heat the test element coated with the aniline - indole copolymer nanosheet array / graphene oxide to 50°C and age it for 48 h;

[0204] Step D: Place the test element coated with the aniline - indole copolymer nanosheet array / graphene oxide composite material in the Narui MA1.0 gas - sensitive test system, adjust the temperature to 35°C, inject a dibutyl phthalate concentration of 300 ppb and record the response value;

[0205] The material of Example 8 has a response value of 26.1% to 300 ppb of dibutyl phthalate.

[0206] Application Example 9:

[0207] This application example provides the test results of the pyrrole - indole copolymer nanosheet array / graphene oxide composite material of the present invention for detecting the concentration of dibutyl phthalate at 35°C.

[0208] The specific test method includes the following steps:

[0209] Step A: Disperse the pyrrole - indole copolymer nanosheet array / graphene oxide composite material prepared in Example 9 in absolute ethanol and grind it into a slurry. The mass ratio of the pyrrole - indole copolymer nanosheet array / graphene oxide composite material to absolute ethanol is 1:10;

[0210] Step B: Uniformly coat 1 μL of the slurry - like material on the substrate (1×1 mm 2 ) of the MEMS test element and let it dry;

[0211] Step C: Heat the test element coated with the pyrrole-indole copolymer nanosheet array / graphene oxide composite to 50 °C and age it for 48 h;

[0212] Step D: Place the test element coated with the pyrrole-indole copolymer nanosheet array / graphene oxide composite in the Narui MA1.0 gas sensing test system, adjust the temperature to 35 °C, inject 300 ppb of dibutyl phthalate and record the response value;

[0213] For the material of Example 9, the response value to 300 ppb of dibutyl phthalate is 124.6%.

[0214] Application Example 10:

[0215] This application example provides the test results of the pyrrole-indole copolymer nanosheet array / graphene oxide composite of the present invention for detecting the concentration of dibutyl phthalate at 35 °C.

[0216] The specific test method includes the following steps:

[0217] Step A: Disperse the pyrrole-indole copolymer nanosheet array / graphene oxide composite prepared in Example 10 in absolute ethanol and grind it into a slurry. The mass ratio of the pyrrole-indole copolymer nanosheet array / graphene oxide composite to absolute ethanol is 1:10;

[0218] Step B: Uniformly coat 1 μL of the slurry material on the substrate (1×1 mm 2 ) of the MEMS test element and air-dry it;

[0219] Step C: Heat the test element coated with the pyrrole-indole copolymer nanosheet array / graphene oxide composite to 50 °C and age it for 48 h;

[0220] Step D: Place the test element coated with the pyrrole-indole copolymer nanosheet array / graphene oxide composite in the Narui MA1.0 gas sensing test system, adjust the temperature to 35 °C, inject 300 ppb of dibutyl phthalate and record the response value;

[0221] For the material of Example 10, the response value to 300 ppb of dibutyl phthalate is 131.2%.

[0222] In the present invention, the in-situ constructed two-dimensional cross-linked MnO2 array structure guides the polymerization of conductive polymer monomers. The molecular structure and electronic properties of the conductive polymer significantly affect its ability to replicate the template structure, thereby determining the nanoscale array regularity and gas response performance of the composite material. Through systematic comparison, it is found that only the copolymerization combination of pyrrole and indole exhibits a significant synergistic enhancement effect. The reason is as follows: Pyrrole molecules have a high charge density and free radical polymerization activity, enabling the construction of a high-quality conductive backbone; while indole molecules have a large conjugated area and excellent π-π stacking ability, which is conducive to stable adsorption and expansion on the surface of the two-dimensional template. The copolymerization of the two can be carried out synergistically under the guidance of the MnO2 cross-template for ordered arrangement and polymerization, forming a highly regular copolymer nanosheet array.

[0223] Experiments have confirmed that the composite material prepared from the pyrrole-indole copolymerization system (Example 4) has a response value as high as 106.2% to 300 ppb dibutyl phthalate, which is much higher than that of the materials of pyrrole alone (31.3%) and indole alone (37.1%), demonstrating typical synergistic effects. In contrast, due to its relatively high oxidation polymerization potential, large rigidity, and weak π-stacking ability, aniline is difficult to form a regular copolymerization structure under the guidance of the template, and the response value decreases when copolymerized with pyrrole or indole (Examples 7 and 8, which are 28.9% and 26.1% respectively). Thus, it can be seen that the pyrrole-indole combination forms a unique advantage in terms of molecular electronic structure matching and template adaptability.

[0224] In Example 9, based on Example 4, 5 mg of phenylguanidine was added in step E to increase the corresponding value. The reason is that phenylguanidine stabilizes free radicals and promotes polymerization, and the benzene ring enhances the π–π interaction of the template, synergistically improving the array orderliness and response performance.

[0225] The above are the preferred embodiments of the present invention. It should be noted that the present invention is not limited to the exemplary embodiments disclosed above. The essence of the specification is merely to assist those skilled in the relevant art in comprehensively understanding the specific details of the present invention. For those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and refinements, as well as easily conceivable changes or substitutions made within the technical scope disclosed by the present invention, should all be covered within the protection scope of the present invention.

Claims

1. A preparation method of a two-dimensional carbon-based conductive polymer nanosheet array composite material, characterized in that, It includes the following steps: Disperse the two-dimensional carbon-based material into the hydrochloric acid aqueous solution; Add potassium permanganate for hydrothermal reaction; Centrifuge and dry; Disperse it into the hydrochloric acid aqueous solution, add the conductive polymer monomer, and carry out oxidative polymerization reaction; Centrifuge and dry.

2. The preparation method of a two-dimensional carbon-based conductive polymer nanosheet array composite material according to claim 1, characterized in that, It includes the following steps: Disperse the two-dimensional carbon-based material in the hydrochloric acid aqueous solution with a concentration of 0.1-0.5 wt.% to form a uniform suspension; Add potassium permanganate to the suspension, and carry out hydrothermal reaction with the two-dimensional carbon-based material at 120-160 °C for 4-8 hours to generate a carbon-based composite material with a cross two-dimensional manganese dioxide nanosheet structure loaded on the surface; Centrifuge, wash and dry to obtain a two-dimensional manganese dioxide carbon-based composite material; Disperse the above two-dimensional manganese dioxide carbon-based composite material in the hydrochloric acid aqueous solution with a concentration of 0.3-1.8 wt.%, add the conductive polymer monomer, and react at 25-60 °C for 2-8 hours to induce the monomer to undergo oxidative polymerization reaction by manganese dioxide; Centrifuge, wash and dry to obtain the two-dimensional carbon-based conductive polymer nanosheet array composite material.

3. The preparation method of a two-dimensional carbon-based conductive polymer nanosheet array composite material according to claim 2, characterized in that, It includes the following steps: Step A: Disperse the two-dimensional carbon-based material into the hydrochloric acid aqueous solution, mix evenly, and stir at room temperature for 10-30 min to prepare a suspension containing the two-dimensional carbon-based material; Step B: Add potassium permanganate to the suspension containing the two-dimensional carbon-based material, stir at room temperature for 10-30 min to prepare a mixed solution, and place it at 120-160 °C for reaction for 4-8 h to obtain product X; Step C: Centrifuge the product X, wash it with deionized water, and then dry it in vacuum at 35-55 °C to obtain a two-dimensional manganese dioxide carbon-based composite material; Step D: Disperse the two-dimensional manganese dioxide carbon-based composite material into the hydrochloric acid aqueous solution to prepare a dispersion containing the two-dimensional manganese dioxide carbon-based composite material; Step E: Add the conductive polymer monomer to the dispersion containing the two-dimensional manganese dioxide carbon-based composite material, and place it at 25-60 °C for reaction for 2-8 h to obtain product Y; Step F: Centrifuge the product Y, wash it with deionized water, and then dry it in vacuum at 35-55 °C to obtain the two-dimensional carbon-based conductive polymer nanosheet array composite material.

4. The preparation method of a two-dimensional carbon-based conductive polymer nanosheet array composite material according to claim 3, characterized in that, In the step A, the two-dimensional carbon-based material is graphene oxide, reduced graphene oxide, Ti3C2T x MXene, Ti2CT x MXene, Ti3CN MXene, Nb4C3T x MXene, Nb2CT x one or more of MXene; the concentration of the hydrochloric acid aqueous solution is 0.15-0.37 wt.%; the mass ratio of the two-dimensional carbon-based material to the hydrochloric acid aqueous solution is 1:(1-5).

5. The preparation method of a two-dimensional carbon-based conductive polymer nanosheet array composite material according to claim 3, characterized in that, In the step B, the mass ratio of the potassium permanganate to the two-dimensional carbon-based material is (0.05-0.1):

1.

6. The preparation method of a two-dimensional carbon-based conductive polymer nanosheet array composite material according to claim 3, characterized in that, In the step D, the concentration of the hydrochloric acid aqueous solution is 0.3-1.8 wt.%; the mass ratio of the two-dimensional manganese dioxide carbon-based composite material to the hydrochloric acid aqueous solution is 1:(100-250).

7. The preparation method of a two-dimensional carbon-based conductive polymer nanosheet array composite material as described in claim 3, wherein, In the step E, the mass ratio of the conductive polymer monomer to the dispersion containing the two-dimensional manganese dioxide carbon-based composite material is 1:(200-600).

8. The preparation method of a two-dimensional carbon-based conductive polymer nanosheet array composite material according to claim 3, characterized in that, The conductive polymer monomer is one or more of pyrrole, aniline, indole and p-phenylenediamine.

9. A two-dimensional carbon-based conductive polymer nanosheet array composite material, characterized in that, It is prepared by the method described in any one of claims 1-8.

10. Application of the two-dimensional carbon-based conductive polymer nanosheet array composite material as described in claim 9 in an organic gas sensor.

Images