A preparation method of MXene-organic molecule hybrid material and its application in photovoltaic storage integrated battery

Abstract

The present invention discloses a method for preparing a MXene-organic molecule hybrid material and its application in a photovoltaic storage integrated battery. The preparation method of the material comprises the following steps: (1) dispersing the etched MXene nanosheets in an organic solvent and dispersing by ultrasonic stripping; (2) adding an aromatic nitro compound to the dispersion, and intercalating the aromatic nitro compound into the MXene nanosheets through electrostatic interaction; (3) adding a cross-linking agent, reacting under the action of a catalyst, and then purifying the product to obtain a MXene-organic molecule hybrid material. The present invention selects a positively charged aromatic nitro compound and a negatively charged MXene to be covalently cross-linked to prepare a hybrid electrode material. At the same time, the pseudocapacitive MXene and the organic molecule with a redox active center synergistically act to effectively improve the specific capacity of the electrode, thereby achieving an increase in the storage capacity of the photogenerated charge, the electrical conductivity of the electrode, and the charge transfer rate.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated photovoltaic and energy storage batteries, and more specifically, to a method for preparing a MXene-organic molecule hybrid material and its application in integrated photovoltaic and energy storage batteries. Background Art

[0002] The rapid development of wearable electronics has put forward new requirements for flexible, self-powered devices. Solar energy, with its abundant reserves, environmental friendliness, and ease of collection, is highly competitive in replacing traditional fossil energy sources. By coupling flexible solar cells with flexible electrochemical energy storage devices, a photovoltaic-storage integrated battery can be constructed. This allows for efficient and rapid storage of photogenerated charges, creating a cost-effective self-charging power source for energy conversion and storage. This photovoltaic-storage integrated battery system requires not only supercapacitors with high energy density and rapid charge storage rates, but also good designability and controllability to optimize parameter matching.

[0003] The structure of electrodes has a decisive influence on the specific capacity of supercapacitors. Organic electrodes, due to their abundant resources, environmental friendliness, and structural designability, hold great research potential for the development of wearable, integrated photovoltaic and energy storage batteries. However, organic electrodes suffer from wide band gaps and low utilization of their redox-active centers. Furthermore, organic molecules are readily soluble in electrolytes, reducing the cycle life of flexible supercapacitors. Loading organic molecules onto inorganic materials, such as MXene, via covalent bonds or π-π interactions can effectively enhance the specific capacity and cycle life of these electrodes.

[0004] Although the synergistic effect of MXene and organic molecules can effectively improve the energy density of supercapacitors, the loading of organic molecules is still relatively low, and there is still huge room for improvement in the energy density of supercapacitors, thereby improving the charge storage efficiency of integrated photovoltaic cells. Therefore, increasing the loading of organic molecules and preparing high-performance MXene-organic molecule hybrid electrode materials are of great significance. Summary of the Invention

[0005] In order to increase the content of redox active centers in MXene-organic molecule hybrid electrode materials, the present invention provides a method for preparing MXene-organic molecule hybrid materials, thereby increasing the loading capacity of organic molecules, preparing supercapacitors with a simple method and low cost, improving energy density, and then constructing a photovoltaic storage integrated battery to achieve rapid charge storage.

[0006] This invention utilizes positively charged aromatic nitro compounds and negatively charged MXene via covalent crosslinking to increase the loading capacity of organic molecules. The pseudocapacitive MXene and organic molecules with redox-active centers work synergistically to enhance the energy density of supercapacitors. The covalent crosslinking of MXene and organic molecules enhances the conductivity and charge transfer rate of the electrode, promoting the storage rate of photogenerated charges.

[0007] In order to achieve the above object, the technical solution of the present invention is as follows:

[0008] In one aspect, the present invention provides a method for preparing a MXene-organic molecule hybrid material, the method comprising the following steps:

[0009] (1) Dispersing the etched MXene nanosheets in an organic solvent and performing ultrasonic exfoliation and dispersion;

[0010] (2) adding an aromatic nitro compound to the dispersion obtained in step (1), and intercalating the aromatic nitro compound into the MXene nanosheets through electrostatic interaction;

[0011] (3) adding a cross-linking agent to the mixed solution obtained in step (2), reacting under the action of a catalyst, and then purifying the product to obtain a MXene-organic molecule hybrid material.

[0012] In the above technical solution, further, in step (1), the organic solvent includes any one of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

[0013] In the above technical solution, further, in step (1), the ultrasonic time is 30-120 minutes.

[0014] In the above technical solution, further, in step (2), the aromatic nitro compound is a molecule containing an -OH aromatic ring, an aromatic heterocycle, an azo aromatic ring structure, and a -NO2 structure, including any one of 4-nitrophenol, 3-nitrophenol, 2-nitrophenol, 2,4-dinitrophenol, 2,4,6-trinitrophenol, 2-nitro-1-naphthol, 4-nitro-1-naphthol, 2,4-dinitronaphthol, 4-hydroxy-4-nitroazobenzene, and 4-(4-nitrophenylazo)-1-naphthol.

[0015] In the above technical solution, further, in step (2), the method of intercalating the aromatic nitro compound into the MXene nanosheet includes any one of standing, mechanical stirring, and ultrasound.

[0016] In the above technical solution, further, in step (3), the cross-linking agent includes any one of dialdehydes, diisocyanates and diacyl chloride organic molecules, preferably any one of p-dibenzaldehyde, p-phenylenediisocyanate and terephthaloyl chloride;

[0017] The catalyst includes any one of triethylamine and dibutyltin dilaurate;

[0018] The reaction temperature is 0-120°C and the reaction time is 1-12h;

[0019] The purification includes any one of filtration washing and centrifugal washing.

[0020] Another aspect of the present invention provides an application of the MXene-organic molecule hybrid material prepared by the above preparation method in a photovoltaic battery, comprising the following steps:

[0021] 1) Using MXene-organic molecule hybrid material as the negative electrode material, the negative electrode material is assembled with the positive electrode material and gel electrolyte into a supercapacitor;

[0022] 2) Couple the supercapacitor with the solar cell to construct a photovoltaic and storage integrated battery.

[0023] In the above technical solution, further, in step 1), the positive electrode material includes any one of MnO2, activated carbon, polyaniline, and V2O5.

[0024] In the above technical solution, further, in step 1), the preparation method of the gel electrolyte is:

[0025] The gel comprises any one of polyacrylamide, polyacrylic acid, and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide;

[0026] The mass fraction of the electrolyte in the gel electrolyte is 5-40wt%;

[0027] The water content of the gel is 30-90 wt%.

[0028] In the above technical solution, further, in step 2), the solar cell includes any one of a perovskite solar cell and a silicon solar cell.

[0029] Compared with the existing methods, the present invention has the following beneficial effects:

[0030] (1) The method of the present invention selects a positively charged aromatic nitro compound and a negatively charged MXene to be covalently cross-linked to prepare a hybrid electrode material. The existing method has a small amount of organic molecule loading, while this method increases the loading amount of organic molecules. At the same time, the pseudocapacitive MXene and the organic molecules with redox active centers work synergistically to effectively improve the specific capacity of the electrode, thereby increasing the storage capacity of photogenerated charges, and improving the conductivity and charge transfer rate of the electrode.

[0031] (2) The preparation method of the present invention is simple to operate and can be extended to more organic molecular systems.

[0032] (3) The method of the present invention utilizes a cross-linking agent to cross-link MXene and aromatic nitro compounds. This covalent bond structure promotes the transfer of electrons from Ti to organic molecules, increases the electron cloud density of organic molecules, enhances the adsorption capacity of organic molecules for ions, improves the conductivity and charge transfer rate of the electrode, and promotes the rapid storage of photogenerated charges. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0034] Figure 1 Schematic diagram of MXene exfoliation in an organic solvent in Example 1;

[0035] Figure 2 The synthetic route of MXene-organic electrode in Example 1;

[0036] Figure 3 is the GCD curve of the MXene-p-nitrophenol electrode in Example 1;

[0037] Figure 4 Schematic diagram of the photovoltaic and storage integrated battery in Example 1. DETAILED DESCRIPTION

[0038] In order to further understand the method of the present invention, a preferred embodiment of the present invention is now given and described in detail with reference to the accompanying drawings.

[0039] Example 1

[0040] (1) Figure 1 As shown, the raw material Ti3AlC2 was etched with LiF and hydrochloric acid HCl as etchants, and then ultrasonically stripped for 1 hour. The etched MXene raw material was dispersed in N,N-dimethylformamide to prepare a dispersion with a mass fraction of 1wt%;

[0041] (2) adding 4-nitrophenol to the dispersion obtained in step (1) and ultrasonically dispersing the mixture for 30 min to intercalate the 4-nitrophenol into the MXene nanosheets;

[0042] (3) adding a crosslinking agent, p-phenylene diisocyanate, to the mixed solution obtained in step (2), dissolving the mixture, and adding 100 μL of a catalyst, dibutyltin dilaurate, to the mixture. The mixture was reacted at 60° C. for 3 h, and the reaction product was centrifuged and washed to obtain a MXene-organic molecule hybrid material.

[0043] (4) Using MXene-organic molecule hybrid material as the negative electrode, MnO2 as the positive electrode, and acrylamide doped with 10 wt% LiCl to prepare a gel electrolyte by free radical polymerization, the positive and negative electrodes were adhered to the upper and lower interfaces of the gel electrolyte to construct an asymmetric supercapacitor;

[0044] (5) The prepared supercapacitor positive and negative electrodes are connected to FA x Cs 1-x The anode and cathode of the PbI3 perovskite solar cell are connected to construct a photovoltaic and storage integrated battery.

[0045] Example 2

[0046] The preparation method is similar to that of Example 1, except that N,N-dimethylformamide is replaced with dimethyl sulfoxide solution.

[0047] Example 3

[0048] The preparation method is similar to that of Example 1, except that the ultrasonic stripping time is set to 30 minutes.

[0049] Example 4

[0050] The preparation method is similar to that of Example 1, except that 2,4-dinitrophenol is used to covalently cross-link MXene.

[0051] Example 5

[0052] The preparation method is similar to that of Example 1, except that mechanical stirring is used to intercalate the organic molecules into the MXene.

[0053] Example 6

[0054] The preparation method is similar to that of Example 1, except that the cross-linking agent is terephthaloyl chloride.

[0055] Example 7

[0056] The preparation method is similar to that of Example 1, except that the catalyst is triethylamine.

[0057] Example 8

[0058] The preparation method is similar to that of Example 1, except that the reaction temperature is set to 80°C.

[0059] Example 9

[0060] The preparation method is similar to that of Example 1, except that the product is purified by suction filtration.

[0061] Example 10

[0062] The preparation method is similar to that of Example 1, except that the positive electrode material is activated carbon.

[0063] Example 11

[0064] The preparation method is similar to that of Example 1, except that the gel electrolyte is polyacrylic acid doped with LiCl.

[0065] Example 12

[0066] The preparation method is similar to that described in Example 1, except that the molar mass of LiCl is 20 wt %.

[0067] Example 13

[0068] The preparation method is similar to that described in Example 1, except that a silicon battery is coupled with a supercapacitor.

[0069] The above content is a detailed description of the present invention. Similar implementations made without departing from the method of the present invention should fall within the scope of protection of the present invention.

Claims

1. A method for preparing a MXene-organic molecule hybrid material, characterized in that: The method comprises the following steps: (1) Dispersing the etched MXene nanosheets in an organic solvent and performing ultrasonic exfoliation and dispersion; (2) adding an aromatic nitro compound to the dispersion obtained in step (1), and intercalating the aromatic nitro compound into the MXene nanosheets through electrostatic interaction; (3) adding a cross-linking agent to the mixed solution obtained in step (2), reacting under the action of a catalyst, and then purifying the product to obtain a MXene-organic molecule hybrid material; In step (2), the aromatic nitro compound is any one of 4-nitrophenol, 3-nitrophenol, 2-nitrophenol, 2,4-dinitrophenol, and 2,4,6-trinitrophenol; In step (3), the cross-linking agent is p-phenylene diisocyanate.

2. The preparation method according to claim 1, characterized in that In step (1), the organic solvent includes any one of N,N-dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone.

3. The preparation method according to claim 1, wherein In step (1), the ultrasonic time is 30-120 min.

4. The preparation method according to claim 1, characterized in that In step (2), the method of intercalating the aromatic nitro compound into the MXene nanosheet includes any one of standing, mechanical stirring, and ultrasonication.

5. The preparation method according to claim 1, characterized in that In step (3), the catalyst includes any one of dibutyltin dilaurate; The reaction temperature is 0-120°C and the reaction time is 1-12 h; The purification includes any one of filtration washing and centrifugal washing.

6. Use of a MXene-organic molecule hybrid material prepared by the preparation method according to any one of claims 1 to 5 in a photovoltaic battery, characterized in that: The application method comprises the following steps: 1) Using MXene-organic molecule hybrid material as the negative electrode material, the negative electrode material is assembled with the positive electrode material and gel electrolyte into a supercapacitor; 2) Couple supercapacitors with solar cells to build a photovoltaic and energy storage integrated battery.

7. The use according to claim 6, characterized in that In step 1), the positive electrode material includes any one of MnO2, activated carbon, polyaniline, and V2O5.

8. The use according to claim 6, characterized in that In step 1), the gel in the gel electrolyte includes any one of polyacrylamide, polyacrylic acid, and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide; The mass fraction of the electrolyte in the gel electrolyte is 5-40wt%; The water content of the gel is 30-90 wt %.

9. The use according to claim 6, characterized in that In step 2), the solar cell includes any one of a perovskite solar cell and a silicon solar cell.

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