High-performance fabric-based electrode materials and their preparation methods and applications

Abstract

The present invention provides a high-performance fabric-based electrode material, a preparation method thereof, and an application thereof. The preparation method of the high-performance fabric-based electrode material comprises the following steps: dissolving a molybdenum source in deionized water to obtain solution A; adding a sulfur source to the obtained solution A to obtain solution B; placing solution B and pre-treated cotton cloth in a high-temperature and high-pressure reactor according to a preset mass ratio, performing a hydrothermal reaction, and obtaining cotton cloth with molybdenum disulfide nanosheets grown on the surface; soaking the cotton cloth with molybdenum disulfide nanosheets grown on the surface in a graphene oxide suspension, drying, repeating the process 2-4 times, and then performing a carbonization treatment to reduce the graphene oxide to reduced graphene oxide and wrap it on the surface of molybdenum disulfide, while carbonizing the cotton cloth to carbonized cotton cloth, thereby obtaining a high-performance fabric-based electrode material. The high-performance fabric-based electrode material prepared by the present invention has excellent conductivity and service life, and has broad application prospects in energy storage.

Description

Technical Field

[0001] The present invention relates to the technical field of flexible batteries, and in particular to a high-performance fabric-based electrode material and a preparation method and application thereof. Background Art

[0002] With the rapid development of wearable electronic devices such as electronic skin, soft robots, weavable wristbands, and foldable displays, research on flexible energy storage materials has increased. Flexible batteries not only possess the characteristics of high energy density, long cycle stability, and environmental friendliness, but also feature lightweight, bendability, large specific surface area, and durability, making them considered ideal flexible energy storage materials. The key to developing flexible batteries lies in the preparation of flexible electrode materials.

[0003] Graphene is a two-dimensional honeycomb-shaped carbon atomic crystal composed of a single layer of carbon atoms. It has excellent conductivity, good light transmittance and a large specific surface area. It can be widely used as a flexible substrate material for storage devices.

[0004] Molybdenum disulfide is a hexagonal graphene-like layered structure composed of three layers of atoms "S-Mo-S". The molybdenum atomic layer is located in the middle. Each molybdenum atom forms a covalent bond with the six surrounding sulfur atoms. There is a weak van der Waals force between the layers. This special layered structure is conducive to the reversible embedding and extraction of ions. At the same time, it has a high theoretical capacity and is regarded as one of the most promising new battery negative electrode materials.

[0005] The current collector, a crucial component of the electrode, significantly impacts battery performance. Traditional copper and aluminum foil current collectors have low surface roughness, weak bonding with the active material, and cannot meet the requirements of flexible electrode materials. Replacing traditional copper and aluminum foil with textiles as flexible current collectors not only allows for the reuse of discarded textiles but also reduces the use of metals like copper and aluminum, thereby reducing costs and conserving energy.

[0006] However, molybdenum disulfide (MoS2) is prone to volume changes during charge and discharge cycles, leading to structural collapse and other issues. Consequently, its cycling and rate performance cannot meet commercial requirements. Furthermore, the poor conductivity of fabrics can affect the conductivity of the current collector and, consequently, the performance of the battery. Currently, metal plating and carbon coating are commonly used to improve fabric conductivity. These methods involve complex synthesis processes and suffer from poor bonding between the electrode active material and the fabric.

[0007] Therefore, by in situ growing molybdenum disulfide on the surface of cotton fabric to ensure strong interfacial bonding between the fabric and molybdenum disulfide, a three-dimensional conductive network of carbonized cotton fabric is constructed and used as a current collector. At the same time, reduced graphene oxide is used to coat molybdenum disulfide to buffer volume changes and further improve conductivity, thereby achieving high capacity, good cycle life and bendable flexible energy storage devices, which is of great significance for the practical application of wearable electronic devices.

[0008] In view of this, it is necessary to design an improved high-performance fabric-based electrode material and its preparation method and application to solve the above problems. Summary of the Invention

[0009] The purpose of the present invention is to provide a high-performance fabric-based electrode material and its preparation method and application. First, molybdenum disulfide is in situ grown on the surface of cotton cloth by hydrothermal reaction, then placed in a suspension containing graphene oxide, and the graphene oxide is coated on the surface of molybdenum disulfide and cotton cloth. Finally, high-temperature carbonization is performed to obtain a high-performance fabric-based electrode material.

[0010] To achieve the above-mentioned object of the invention, the present invention provides a method for preparing a high-performance fabric-based electrode material, comprising the following steps:

[0011] S1. The molybdenum source was dissolved in deionized water to obtain a solution A; a sulfur source was then added to the resulting solution A, stirred and dissolved to obtain a solution B;

[0012] S2. The solution B obtained in step S1 and the pre-treated cotton cloth are placed in a high-temperature and high-pressure reactor according to a preset mass ratio, subjected to a hydrothermal reaction, washed and dried, to obtain a cotton cloth having molybdenum disulfide nanosheets grown on its surface;

[0013] S3. The cotton cloth with molybdenum disulfide nanosheets grown on the surface obtained in step S2 is immersed in a graphene oxide suspension of a certain concentration for 4-10 minutes and dried. The treatment is repeated 2-4 times and then carbonized to reduce the graphene oxide to reduced graphene oxide and wrap it on the surface of molybdenum disulfide. At the same time, the cotton cloth is carbonized to carbonized cotton cloth to obtain a high-performance fabric-based electrode material.

[0014] As a further improvement of the present invention, in step S3, the carbonization treatment is specifically to heat the temperature to 700-900°C at a heating rate of 2-5°C / min and then keep it warm for 3-6 hours; the drying is to dry it in a vacuum oven at 70-90°C for 0.5-1.5 hours.

[0015] As a further improvement of the present invention, in step S3, the concentration of the graphene oxide suspension is 1-3 mg / mL.

[0016] As a further improvement of the present invention, in step S2, the mass ratio of the cotton cloth to the solution B is 0.05-0.15; the temperature of the hydrothermal reaction is 180-200° C., and the reaction time is 20-30 h.

[0017] As a further improvement of the present invention, in step S1, the molybdenum source includes one of sodium molybdate, ammonium molybdate, and ammonium thiomolybdate; and the sulfur source includes one of thiourea, ammonium thiomolybdate, thioacetamide, sodium sulfide, and L-cysteine.

[0018] As a further improvement of the present invention, in step S1, the Mo in the solution A 6+ The concentration of Mo in solution B is 0.006-0.02 mol / L. 6+ The molar concentration ratio of the sulfur source is 0.06-0.08.

[0019] As a further improvement of the present invention, in step S2, the treatment of the pre-treated cotton cloth is specifically to add the cotton cloth to a 1-3 wt% NaOH solution at 80-100° C. for 0.5-1.5 h, and then wash and dry.

[0020] To achieve the above-mentioned purpose of the invention, the present invention also provides a high-performance fabric-based electrode material, which is prepared using the above-mentioned method for preparing a high-performance fabric-based electrode material.

[0021] To achieve the above-mentioned object of the invention, the present invention also provides an application of a high-performance fabric-based electrode material, wherein the high-performance fabric-based electrode material is used to prepare a flexible battery.

[0022] As a further improvement of the present invention, a sodium ion battery prepared using the high-performance textile-based electrode material has an initial discharge specific capacity of 802.6 mAh / g at a current density of 100 mA / g; at a current density of 1 A / g, the capacity is still 227.8 mAh / g after 200 cycles, and the cycle stability is good; a lithium ion battery prepared using the high-performance textile-based electrode material has an initial discharge specific capacity of 1730.3 mAh / g at a current density of 100 mA / g; and the capacity is still as high as 482 mAh / g after 300 cycles.

[0023] The beneficial effects of the present invention are:

[0024] (1) The present invention provides a method for preparing a high-performance fabric-based electrode material. First, molybdenum disulfide is grown in situ on the surface of cotton cloth using a hydrothermal reaction. The molybdenum disulfide is then placed in a suspension containing graphene oxide, and the graphene oxide is coated on the surfaces of the molybdenum disulfide and cotton cloth. Finally, the high-performance fabric-based electrode material is obtained by high-temperature carbonization. Cotton cloth with a rough surface and containing active groups is selected as the base material. This allows a large number of molybdenum disulfide nanosheets to bond with the cotton cloth and adhere tightly to the cotton fiber surface, preventing them from falling off easily, thereby enhancing the interfacial bonding between the molybdenum disulfide and the cotton cloth. During the carbonization process, on the one hand, the graphene oxide containing many active groups on the surface is reduced to reduced graphene oxide with high stability and high conductivity, thereby improving the overall conductivity; on the other hand, the groups contained in the cotton fibers are decomposed into small molecular gases and released in a high temperature environment, thereby changing the structure of the cotton cloth and obtaining a porous carbonized cotton cloth with a loose structure. At the same time, the carbon fiber lines of the carbonized cotton cloth are entangled to varying degrees to form a three-dimensional conductive network. In this process, the molybdenum disulfide coated with graphene moves relative to each other as the small molecular gases are released, and is embedded between different carbon fibers of the carbonized cotton cloth, thereby obtaining a high-performance fabric-based electrode material with a special three-dimensional network structure. The synergistic effect of reduced graphene oxide, molybdenum disulfide and the carbonized cotton cloth with a three-dimensional conductive network is utilized to improve the conductivity of the electrode material. At the same time, the protective effect of reduced graphene oxide on molybdenum disulfide is utilized to slow down its volume expansion and improve the service life of the electrode material. In addition, the present invention first performs a hydrothermal reaction and then performs high-temperature carbonization, which is more conducive to the uniform attachment of molybdenum disulfide coated with graphene and does not destroy the structure of the three-dimensional conductive network. The present invention can utilize discarded fabrics as base materials, thereby saving energy.

[0025] (2) The present invention is simple to operate and easy to prepare. After carbonization, the cotton cloth forms a woven three-dimensional conductive carbon fiber network to improve the electrical conductivity of the material. At the same time, the surface-coated reduced graphene oxide can alleviate the problems of rapid volume expansion and structural collapse of molybdenum disulfide materials during high-rate charge and discharge of the battery, and further improve the electrical conductivity of the material, thereby effectively improving the electrochemical performance of sodium ion batteries and their commercial applications.

[0026] (3) The high-performance fabric-based electrode material prepared by the present invention is flexible and can be directly used as the negative electrode material of sodium ion batteries without the need for binders and conductive agents. The battery prepared using this material as the negative electrode material has an initial discharge capacity of 802.6 mAh / g at a current density of 100 mA / g. At a current density of 1 A / g, the capacity is still 227.8 mAh / g after 200 cycles, and the cycle stability is good. It is an excellent sodium ion battery negative electrode material with broad application prospects in energy storage. At the same time, it provides new ideas and methods for the preparation of other flexible self-supporting negative electrode materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is the XRD pattern of the high-performance fabric-based electrode material prepared in Example 1 of the present invention.

[0028] Figure 2 This is a scanning electron microscope image of the high-performance fabric-based electrode material prepared in Example 1 of the present invention, with a scale of 5 μm.

[0029] Figure 3 This is the charge-discharge curve of the button battery prepared in Example 5 of the present invention at a current density of 100 mA / g for the first five cycles.

[0030] Figure 4 This is a cycle curve diagram of the button battery prepared in Example 5 of the present invention at a current density of 1 A / g. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] It should also be noted here that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solutions of the present invention are shown in the drawings, while other details that are not closely related to the present invention are omitted.

[0033] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0034] See also Figure 1-4 As shown, the present invention provides a method for preparing a high-performance fabric-based electrode material, comprising the following steps:

[0035] S1. Preparation of a mixed solution containing a molybdenum source and a sulfur source:

[0036] A molybdenum source is dissolved in deionized water and stirred to dissolve to obtain a solution A; a sulfur source is then added to the obtained solution A and stirred to dissolve to obtain a solution B.

[0037] Specifically, the molybdenum source includes one of sodium molybdate, ammonium molybdate, and ammonium thiomolybdate, preferably sodium molybdate (Na2MoO4·2H2O); the sulfur source includes one of thiourea, ammonium thiomolybdate, thioacetamide, sodium sulfide, and L-cysteine, preferably thiourea [CS(NH2)2].

[0038] Mo in solution A 6+The concentration of Mo in solution B is 0.006-0.02 mol / L. 6+ The molar concentration ratio of the sulfur source (i.e., thiourea) is 0.06-0.08.

[0039] S2. Preparation of cotton cloth with MoS2 nanosheets grown on its surface (MoS2 / cotton cloth):

[0040] The cotton cloth is added to a 1-3 wt% NaOH solution and treated at 80-100°C for 0.5-1.5 hours to remove impurities and oil stains on the surface of the cotton cloth. The cotton cloth is then taken out, washed, and dried to obtain pre-treated cotton cloth.

[0041] The solution B obtained in step S1 and the pre-treated cotton cloth are placed in a high-temperature and high-pressure reactor according to a preset mass ratio to perform a hydrothermal reaction. After washing and drying, a cotton cloth with molybdenum disulfide nanosheets grown on the surface is obtained, that is, molybdenum disulfide nanosheets / cotton cloth is obtained.

[0042] Specifically, the mass ratio of cotton cloth to solution B is 0.05-0.15; the temperature of the hydrothermal reaction is 180-200° C., and the reaction time is 20-30 h.

[0043] In this process, sodium molybdate and thiourea react in a high-temperature and high-pressure reactor to produce molybdenum disulfide. The reaction equation is as follows:

[0044] (1) First, thiourea reacts with water at high temperature:

[0045] CS(NH2)2+2H2O = 2NH3+CO2+H2S

[0046] (2) Na2MoO4 reacts with the generated H2S gas:

[0047] 4Na2MoO4+9H2S = 4MoS2+Na2SO4+6NaOH+6H2O

[0048] The generated molybdenum disulfide (MoS2) has a "sandwich" layered structure, with quite a lot of Mo-S facets, a large specific surface area, and high reactivity. In a high-temperature and high-pressure reactor, molybdenum disulfide nanosheets grow in situ on the surface of cotton cloth. Because the surface of cotton cloth is relatively rough and contains active groups such as hydroxyl groups, a large number of molybdenum disulfide nanosheets bond with cotton cloth and then tightly adhere to the surface of cotton fibers, and will not fall off easily.

[0049] S3. Preparation of high-performance fabric-based electrode materials (reduced graphene oxide / molybdenum disulfide / carbonized cotton cloth):

[0050] The cotton cloth with molybdenum disulfide nanosheets grown on the surface obtained in step S2 is soaked in a graphene oxide suspension with a concentration of 1-3 mg / mL for 4-10 minutes, preferably 5 minutes, and the graphene oxide is evenly attached to the surface of the cotton cloth with molybdenum disulfide nanosheets, and the molybdenum disulfide is wrapped, dried, and the process is repeated 2-4 times.

[0051] The dried cotton cloth was carbonized to produce a high-performance fabric-based electrode material. The carbonization process reduced graphene oxide to reduced graphene oxide, which was then coated on the surface of molybdenum disulfide. It also carbonized the cotton cloth, resulting in carbonized cotton cloth.

[0052] The carbonization treatment is specifically to heat the temperature to 700-900°C at a heating rate of 2-5°C / min and keep it warm for 3-6 hours; the drying is to dry it in a vacuum oven at 70-90°C for 0.5-1.5 hours.

[0053] Because graphene oxide contains many active groups on its surface, it is relatively unstable. The reduced graphene oxide obtained by carbonization removes these active groups, making it more stable and also improving its conductivity. During the carbonization process, the groups on the cotton fibers decompose into small gas molecules at high temperatures and release them, changing the structure of the cotton cloth, resulting in a fluffy, porous carbonized cotton cloth. Simultaneously, the carbon fibers of the carbonized cotton cloth become intertwined to varying degrees, forming a three-dimensional conductive network. During this process, the graphene-coated molybdenum disulfide (MoS2) moves relative to the carbonized cotton cloth as the small gas molecules are released, becoming embedded between the different carbon fibers of the carbonized cotton cloth, resulting in a high-performance fabric-based electrode material with a unique three-dimensional network structure. The interaction between the large π bonds of reduced graphene oxide and the electronic structure of the MoS2 surface creates a new electronic structure, which interacts with the three-dimensional conductive network formed by the carbonized cotton cloth, increasing the electron transfer rate of the high-performance fabric-based electrode material and thus improving its conductivity.

[0054] The present invention also provides a high-performance fabric-based electrode material, which is prepared using the above-mentioned method for preparing the high-performance fabric-based electrode material.

[0055] The present invention also provides an application of a high-performance textile-based electrode material, which can be used to prepare flexible batteries. For example, a sodium-ion battery prepared using this high-performance textile-based electrode material exhibited an initial discharge capacity of 802.6 mAh / g at a current density of 100 mA / g. At a current density of 1 A / g, the capacity remained at 227.8 mAh / g after 200 cycles, demonstrating excellent cycling stability. The molybdenum source concentration, sulfur source concentration, graphene concentration, and the temperature and duration of the hydrothermal reaction and high-temperature carbonization during the preparation of this high-performance textile-based electrode material all affect the performance of the prepared electrode material.

[0056] The present invention is described in detail below through a number of embodiments:

[0057] Example 1

[0058] A method for preparing a high-performance fabric-based electrode material comprises the following steps:

[0059] S1. Preparation of a mixed solution containing a molybdenum source and a sulfur source:

[0060] Dissolve 150 mg of Na2MoO4·2H2O in 60 mL of deionized water and stir for 15 min until completely dissolved to obtain solution A, in which Mo 6+ The concentration of Mo is 0.01 mol / L; 600 mg of thiourea is added to the obtained solution A and stirred for 15 min until it is completely dissolved to obtain solution B, in which Mo 6+ The molar concentration ratio of thiourea is 0.077.

[0061] S2. Preparation of cotton cloth with MoS2 nanosheets grown on its surface (MoS2 / cotton cloth):

[0062] 20 g of cotton cloth was added to a 2 wt % NaOH solution and treated at 90°C for 1 h to remove impurities and oil stains on the surface of the cotton cloth. The cotton cloth was then taken out, washed, and dried to obtain pre-treated cotton cloth.

[0063] The solution B obtained in step S1 and the pre-treated cotton cloth were placed in a high-temperature and high-pressure reactor for a hydrothermal reaction. The resulting product was washed twice with deionized water and once with ethanol, and vacuum-dried at 80°C for 12 h to obtain a cotton cloth with molybdenum disulfide nanosheets grown on the surface, that is, molybdenum disulfide nanosheets / cotton cloth.

[0064] Specifically, the mass ratio of cotton cloth to solution B was 0.082; the temperature of the hydrothermal reaction was 190° C., and the reaction time was 24 h.

[0065] S3. Preparation of high-performance fabric-based electrode materials (reduced graphene oxide / molybdenum disulfide / carbonized cotton cloth):

[0066] The cotton cloth with molybdenum disulfide nanosheets grown on the surface obtained in step S2 was soaked in a 2 mg / mL graphene oxide suspension for 5 min. Graphene oxide was evenly attached to the surface of the cotton cloth with molybdenum disulfide nanosheets and wrapped with molybdenum disulfide. The cotton cloth was vacuum dried at 80 ° C for 12 h, and the steps were repeated 3 times.

[0067] The dried cotton cloth was carbonized by heating the temperature to 700°C at a rate of 2°C / min and maintaining the temperature for 6 h to obtain a high-performance fabric-based electrode material.

[0068] The crystal structure and phase of molybdenum disulfide in the high performance fabric-based electrode material prepared in this example were measured by X-ray diffractometer. The results are as follows: Figure 1 As shown by Figure 1 The XRD pattern shows that the position of the (002) crystal peak of MoS2 has shifted, which is mainly due to the NH 4+ Embedded into the interlayer of MoS2, it causes the (002) crystal plane of MoS2 to expand, and then the position of its peak is shifted. 4+ The embedding of ions will expand the interlayer spacing, which is more conducive to the reversible embedding and extraction of ions and facilitates the transmission of ions.

[0069] The high performance fabric-based electrode material finally obtained in this embodiment was subjected to morphology measurement. The results are as follows: Figure 2 The scanning electron microscope image shown. Figure 2 It can be seen that in this high-performance fabric-based electrode material, reduced graphene oxide is wrapped on the surface of molybdenum disulfide, and at the same time, molybdenum disulfide nanosheets with reduced graphene oxide wrapped on the surface are uniformly grown on the surface of the carbonized cotton cloth.

[0070] Example 2

[0071] A method for preparing a high-performance fabric-based electrode material comprises the following steps:

[0072] S1. Preparation of a mixed solution containing a molybdenum source and a sulfur source:

[0073] Dissolve 150 mg of Na2MoO4·2H2O in 60 mL of deionized water and stir for 15 min until completely dissolved to obtain solution A, in which Mo 6+ The concentration of Mo is 0.01 mol / L; 600 mg of thiourea is added to the obtained solution A and stirred for 15 min until it is completely dissolved to obtain solution B, in which Mo 6+ The molar concentration ratio of thiourea is 0.077.

[0074] S2. Preparation of cotton cloth with MoS2 nanosheets grown on its surface (MoS2 / cotton cloth):

[0075] 20 g of cotton cloth was added to a 2 wt % NaOH solution and treated at 90°C for 1 h to remove impurities and oil stains on the surface of the cotton cloth. The cotton cloth was then taken out, washed, and dried to obtain pre-treated cotton cloth.

[0076] The solution B obtained in step S1 and the pre-treated cotton cloth were placed in a high-temperature and high-pressure reactor for a hydrothermal reaction. The resulting product was washed twice with deionized water and then twice with ethanol, and vacuum-dried at 80°C for 12 h to obtain a cotton cloth with molybdenum disulfide nanosheets grown on the surface, that is, molybdenum disulfide nanosheets / cotton cloth.

[0077] Specifically, the mass ratio of cotton cloth to solution B was 0.082; the temperature of the hydrothermal reaction was 190° C., and the reaction time was 24 h.

[0078] S3. Preparation of high-performance fabric-based electrode materials (reduced graphene oxide / molybdenum disulfide / carbonized cotton cloth):

[0079] The cotton cloth with molybdenum disulfide nanosheets grown on the surface obtained in step S2 was soaked in a 2 mg / mL graphene oxide suspension for 5 min. Graphene oxide was evenly attached to the surface of the cotton cloth with molybdenum disulfide nanosheets and wrapped with molybdenum disulfide. The cotton cloth was vacuum dried at 80 ° C for 12 h, and the steps were repeated 3 times.

[0080] The dried cotton cloth was carbonized by heating it to 800°C at a heating rate of 2°C / min and maintaining it for 6 hours to obtain a high-performance fabric-based electrode material.

[0081] Example 3

[0082] A method for preparing a high-performance fabric-based electrode material comprises the following steps:

[0083] S1. Preparation of a mixed solution containing a molybdenum source and a sulfur source:

[0084] Dissolve 150 mg of Na2MoO4·2H2O in 60 mL of deionized water and stir for 15 min until completely dissolved to obtain solution A, in which Mo 6+ The concentration of Mo is 0.01 mol / L; 600 mg of thiourea is added to the obtained solution A and stirred for 15 min until it is completely dissolved to obtain solution B, in which Mo 6+ The molar concentration ratio of thiourea is 0.077.

[0085] S2. Preparation of cotton cloth with MoS2 nanosheets grown on its surface (MoS2 / cotton cloth):

[0086] 20 g of cotton cloth was added to a 2 wt % NaOH solution and treated at 90°C for 1 h to remove impurities and oil stains on the surface of the cotton cloth. The cotton cloth was then taken out, washed, and dried to obtain pre-treated cotton cloth.

[0087] The solution B obtained in step S1 and the pre-treated cotton cloth were placed in a high-temperature and high-pressure reactor for a hydrothermal reaction. The resulting product was washed three times with deionized water and three times with ethanol, and vacuum-dried at 80°C for 12 h to obtain a cotton cloth with molybdenum disulfide nanosheets grown on the surface, that is, molybdenum disulfide nanosheets / cotton cloth.

[0088] Specifically, the mass ratio of cotton cloth to solution B was 0.082; the temperature of the hydrothermal reaction was 190° C., and the reaction time was 24 h.

[0089] S3. Preparation of high-performance fabric-based electrode materials (reduced graphene oxide / molybdenum disulfide / carbonized cotton cloth):

[0090] The cotton cloth with molybdenum disulfide nanosheets grown on the surface obtained in step S2 was soaked in a 1 mg / mL graphene oxide suspension for 5 min. Graphene oxide was evenly attached to the surface of the cotton cloth with molybdenum disulfide nanosheets and wrapped with molybdenum disulfide. The cotton cloth was vacuum dried at 80°C for 12 h, and the steps were repeated 4 times.

[0091] The dried cotton cloth was carbonized by heating it to 900°C at a heating rate of 2°C / min and maintaining it for 6 hours to obtain a high-performance fabric-based electrode material.

[0092] Example 4

[0093] A method for preparing a high-performance fabric-based electrode material comprises the following steps:

[0094] S1. Preparation of a mixed solution containing a molybdenum source and a sulfur source:

[0095] 300 mg of Na2MoO4·2H2O was dissolved in 60 mL of deionized water and stirred for 15 min until completely dissolved to obtain solution A, in which Mo 6+ The concentration of Mo is 0.02 mol / L; 1.2 g of thiourea is added to the obtained solution A and stirred for 15 min until it is completely dissolved to obtain solution B, in which Mo 6+ The molar concentration ratio of thiourea is 0.077.

[0096] S2. Preparation of cotton cloth with MoS2 nanosheets grown on its surface (MoS2 / cotton cloth):

[0097] 20 g of cotton cloth was added to a 2 wt % NaOH solution and treated at 90°C for 1 h to remove impurities and oil stains on the surface of the cotton cloth. The cotton cloth was then taken out, washed, and dried to obtain pre-treated cotton cloth.

[0098] The solution B obtained in step S1 and the pre-treated cotton cloth were placed in a high-temperature and high-pressure reactor for a hydrothermal reaction. The resulting product was washed twice with deionized water and then twice with ethanol, and vacuum-dried at 80°C for 12 h to obtain a cotton cloth with molybdenum disulfide nanosheets grown on the surface, that is, molybdenum disulfide nanosheets / cotton cloth.

[0099] Specifically, the mass ratio of cotton cloth to solution B was 0.082; the temperature of the hydrothermal reaction was 190° C., and the reaction time was 24 h.

[0100] S3. Preparation of high-performance fabric-based electrode materials (reduced graphene oxide / molybdenum disulfide / carbonized cotton cloth):

[0101] The cotton cloth with molybdenum disulfide nanosheets grown on the surface obtained in step S2 was soaked in a 3 mg / mL graphene oxide suspension for 5 min. Graphene oxide was evenly attached to the surface of the cotton cloth with molybdenum disulfide nanosheets and wrapped with molybdenum disulfide. The cotton cloth was vacuum dried at 80 ° C for 12 h, and the steps were repeated twice.

[0102] The dried cotton cloth was carbonized by heating it to 700°C at a heating rate of 2°C / min and maintaining it for 6 hours to obtain a high-performance fabric-based electrode material.

[0103] Example 5

[0104] An application of a high-performance fabric-based electrode material, the high-performance fabric-based electrode material prepared in Example 1 is used as a negative electrode material for a sodium ion battery to prepare a button battery.

[0105] Specifically, the preparation of the electrode sheet does not require the addition of a binder and a conductive agent. The high-performance fabric-based electrode material prepared in Example 1 can be directly cut into discs with a diameter of 1 cm using a slicer to obtain a MoS2 loading of 1.3-1.6 mg / cm 2 The electrodes are then assembled in an argon-filled glove box into a coin cell battery similar to a CR2032 (except that the lithium is replaced with sodium). A sodium metal sheet is placed on the negative electrode shell as the counter electrode, followed by a glass fiber separator. An electrolyte (sodium trifluoromethanesulfonate (NaCF3SO3) dissolved in diethylene glycol dimethyl ether (DEGDME)) is added dropwise. The prepared electrode sheet is then placed in the battery, followed by a gasket, spring, and positive electrode shell. Finally, the battery is packaged using a battery packaging machine to produce a coin cell battery suitable for testing.

[0106] like Figure 3 As shown, the negative electrode material prepared by the high-performance fabric-based electrode has an initial discharge capacity of 802.6 mAh / g at a current density of 100 mA / g; starting from the second time, the discharge capacity decreases, but after five cycles, the discharge capacity is basically the same as the second time; after 60 cycles, the capacity is 409.4 mAh / g.

[0107] like Figure 4 As shown in the figure, the negative electrode material prepared by the high-performance textile-based electrode still has a capacity of 227.8 mAh / g after 200 cycles at a current density of 1 A / g. This result shows that the high-performance textile-based electrode material exhibits excellent electrochemical performance as a negative electrode material for sodium-ion batteries.

[0108] Examples 6-8

[0109] An application of a high-performance fabric-based electrode material, wherein the high-performance fabric-based electrode materials prepared in Examples 2-4 are used as negative electrode materials for sodium-ion batteries to prepare button batteries. (The button battery prepared in Example 2 corresponds to Example 6; the button battery prepared in Example 3 corresponds to Example 7; and the button battery prepared in Example 4 corresponds to Example 8)

[0110] The button cells prepared in Examples 5-8 were subjected to performance tests. The results are shown in Table 1. The initial discharge capacity refers to the initial discharge capacity at a current density of 100 mA / g, and the capacity after 60 cycles refers to the capacity after 60 cycles at a current density of 100 mA / g:

[0111] Table 1 Relevant properties of button batteries prepared in Examples 5-8

[0112]

[0113] As can be seen from Table 1, with the increase of carbonization temperature (Examples 5, 6, and 7), the initial capacity and cycle stability of the prepared button batteries decreased. This may be because when the carbonization temperature is high, it will affect the structure of the carbonized cotton cloth, and then affect the structure of the high-performance fabric-based electrode material.

[0114] It can be seen from Example 8 that with the increase of the molybdenum source concentration and the graphene concentration, the initial capacity of the prepared button battery decreases, and the cycle stability is not as good as that of Examples 5-7 (the battery in Example 8 cannot be used before the cycle reaches 60 cycles). This may be because, with the increase of the molybdenum source concentration, the molybdenum disulfide attached to the surface of the cotton cloth is more crowded, and the excessive molybdenum disulfide expands greatly in volume during the charge and discharge process. The graphene cannot buffer its volume change well, thereby affecting the performance of the button battery.

[0115] Example 9

[0116] An application of a high-performance fabric-based electrode material, compared with Example 5, is different in that the high-performance fabric-based electrode material prepared in Example 1 is used as a lithium-ion battery negative electrode material to prepare a button battery, and the specific preparation method is the same as that of Example 5.

[0117] The negative electrode material prepared from this high-performance textile-based electrode exhibited an initial discharge capacity of 1730.3 mAh / g at a current density of 100 mA / g; after 300 cycles, the capacity remained as high as 482 mAh / g. This demonstrates that both lithium-ion and sodium-ion batteries prepared from this high-performance textile-based electrode material exhibit excellent performance.

[0118] Comparative Example 1

[0119] A method for preparing a high-performance fabric-based electrode material, compared with Example 1, differs in that the cotton cloth is first carbonized and then placed in a high-temperature and high-pressure reactor with a molybdenum source and a sulfur source for a hydrothermal reaction. The prepared high-performance fabric-based electrode material is used as a negative electrode material for a sodium ion battery to prepare a button battery. When the current density is 100 mA / g, the first discharge specific capacity is 700.7 mAh / g; when the current density is 1 A / g, the capacity after 200 cycles is 111.7 mAh / g, which is significantly lower than the button battery prepared in Example 1. This is mainly because, after the cotton cloth is carbonized at high temperature, its molecular arrangement changes, and the structure of the cotton cloth also changes accordingly, forming a three-dimensional grid structure. At the same time, the hydrophilic groups on the surface of the carbonized cotton cloth are reduced. When the carbonized cotton cloth with a three-dimensional grid structure undergoes hydrothermal reaction, in a high-temperature and high-pressure reactor, on the one hand, due to the reduction of hydrophilic groups on the surface of the carbonized cotton cloth, and on the other hand, due to the difference in structure between the cotton cloth and the carbonized cotton cloth, the molybdenum disulfide produced by the reaction of the molybdenum source and the sulfur source is not easy to adhere to the surface of the carbonized cotton cloth, and the carbonized cotton cloth is prone to fiber breakage, which in turn makes the performance of the prepared button battery worse.

[0120] Comparative Example 2

[0121] A method for preparing a high-performance fabric-based electrode material, compared to Example 1, differs in that, instead of the graphene oxide wrapping step, cotton cloth with molybdenum disulfide nanosheets grown on its surface is directly carbonized. This high-performance fabric-based electrode material is used as the negative electrode material for a sodium-ion battery fabricated into a button cell. At a current density of 100 mA / g, the initial discharge capacity is 747.3 mAh / g; after 60 cycles, the capacity is 377.8 mAh / g, significantly lower than the button cell prepared in Example 1. This demonstrates that the presence of graphene not only increases the battery's conductivity but also prevents the volume expansion of molybdenum disulfide, thereby extending the battery's service life.

[0122] In summary, the present invention provides a high-performance fabric-based electrode material, its preparation method and application, by in situ growing molybdenum disulfide on the surface of cotton fabric to ensure strong interfacial bonding between the fabric and molybdenum disulfide, and constructing a three-dimensional carbonized cotton fabric conductive network and using it as a current collector. At the same time, reduced graphene oxide is used to coat molybdenum disulfide to buffer volume changes and further improve conductivity, thereby achieving high capacity, good cycle life and bendable flexible energy storage devices, which are of great significance to the practical application of wearable electronic devices.

[0123] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a high-performance fabric-based electrode material, characterized by: The steps include: S1. The molybdenum source is dissolved in deionized water to obtain solution A; a sulfur source is added to the resulting solution A, stirred and dissolved to obtain solution B; Mo in solution A 6+ The concentration of Mo in solution B is 0.006-0.02 mol / L. 6+ The molar concentration ratio to the sulfur source is 0.06-0.08; S2. The solution B obtained in step S1 and the pre-treated cotton cloth are placed in a high-temperature and high-pressure reactor in a predetermined mass ratio for hydrothermal reaction. After washing and drying, a cotton cloth having molybdenum disulfide nanosheets grown on its surface is obtained. The mass ratio of the cotton cloth to the solution B is 0.05-0.

15. The hydrothermal reaction temperature is 180-200°C and the reaction time is 20-30 hours. S3. The cotton cloth with molybdenum disulfide nanosheets grown on the surface obtained in step S2 is immersed in a graphene oxide suspension of a certain concentration for 4-10 minutes and dried. The treatment is repeated 2-4 times and then carbonized to reduce the graphene oxide to reduced graphene oxide and wrap it on the surface of molybdenum disulfide. At the same time, the cotton cloth is carbonized to carbonized cotton cloth to obtain a high-performance fabric-based electrode material; the carbonization treatment is specifically to heat the temperature to 700-900°C at a heating rate of 2-5°C / min and keep it warm for 3-6 hours.

2. The method for preparing a high-performance fabric-based electrode material according to claim 1, wherein: In step S3, the drying is carried out in a vacuum oven at 70-90° C. for 0.5-1.5 h.

3. The method for preparing a high-performance fabric-based electrode material according to claim 1, wherein: In step S3, the concentration of the graphene oxide suspension is 1-3 mg / mL.

4. The method for preparing a high-performance fabric-based electrode material according to claim 1, wherein: In step S1, the molybdenum source includes one of sodium molybdate, ammonium molybdate, and ammonium thiomolybdate; and the sulfur source includes one of thiourea, ammonium thiomolybdate, thioacetamide, sodium sulfide, and L-cysteine.

5. The method for preparing a high-performance fabric-based electrode material according to claim 1, wherein: In step S2, the pre-treated cotton cloth is treated by adding the cotton cloth into a 1-3 wt% NaOH solution at 80-100°C for 0.5-1.5 hours, followed by washing and drying.

6. A high-performance fabric-based electrode material, characterized by: The high-performance fabric-based electrode material is prepared by the method for preparing the high-performance fabric-based electrode material according to any one of claims 1 to 5.

7. Use of a high-performance fabric-based electrode material prepared by the method for preparing a high-performance fabric-based electrode material according to any one of claims 1 to 5 or the high-performance fabric-based electrode material according to claim 6, characterized in that: The high-performance fabric-based electrode material is used to prepare flexible batteries.

8. The use of the high-performance textile-based electrode material according to claim 7, characterized in that: The sodium ion battery prepared using the high-performance textile-based electrode material has an initial discharge specific capacity of 802.6 mAh / g at a current density of 100 mA / g; at a current density of 1 A / g, the capacity is still 227.8 mAh / g after 200 cycles, and the cycle stability is good; the lithium ion battery prepared using the high-performance textile-based electrode material has an initial discharge specific capacity of 1730.3 mAh / g at a current density of 100 mA / g; and the capacity is still as high as 482 mAh / g after 300 cycles.

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