PBFDO / Ti3C2TX self-supporting film as well as preparation method and application thereof

Abstract

The invention discloses a PBFDO / Ti3C2TX self-supporting film as well as a preparation method and application thereof, and belongs to the field of electrode material preparation. The PBFDO / Ti < 3 > C < 2 > T < X > self-supporting thin film prepared by the preparation method disclosed by the invention is prepared by compounding PBFDO with Ti < 3 > C < 2 > T < X >. Compared with the prior art, the PBFDO / Ti3C2TX self-supporting film prepared by the invention has good capacitive property and high stability, the preparation method is simple, efficient, safe and environment-friendly, and a new thought is provided for preparing a supercapacitor electrode material with excellent capacitive property. The method can be widely applied to the fields of portable electronic equipment, electric automobiles and the like, and has wide application prospects and market potential.

Description

Technical Field

[0001] The present invention relates to the field of electrode material preparation, in particular to a PBFDO / Ti3C2T X Self-supporting film and preparation method and application thereof. Background Art

[0002] With the development of society and technology, human beings are facing serious problems such as increasing energy shortage and worsening climate. In order to effectively alleviate and solve these problems, it is urgent to promote the transformation of traditional energy to sustainable, environmentally friendly and widely available energy materials. Therefore, the research and development of clean, low energy loss, high capacity, cyclic stability and high utilization rate energy conversion and storage equipment has become crucial.

[0003] Electrode materials are key factors in determining the performance of batteries, capacitors, and electrosorption. Ordinary powdered electrode materials usually need to be mixed and dissolved with binders and conductive materials, and then coated to form films. The added binders and solubilizers will seriously affect the performance of the materials themselves; and the coating process is complex and requires a high level of operator skills, which does not promote its large-scale application. Therefore, it is very important to develop self-supporting electrode materials with excellent performance that can be directly applied.

[0004] At present, most of the preparation methods of polymer composite electrodes use conductive agents and binders. The addition of conductive agents will increase the dead volume of the electrode and affect its energy storage efficiency. The addition of binders will not only increase the dead volume and internal resistance of the electrode system, but also may block the pores in the electrode material, reduce the effective specific surface area of ​​the electrode, and thus affect the penetration of the electrolyte and the energy storage capacity of the electrode. At the same time, the commonly used physical bonding method may not be able to maintain the stable existence of the material on the electrode surface all the time, especially under high current density and long cycle conditions, the active material is easy to fall off from the electrode surface, resulting in a decrease in the material's cycle stability. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a PBFDO / Ti3C2T3 with a simple preparation method, environmental protection, good capacitance and high stability. X Self-supporting film and preparation method and application thereof.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] On the one hand, the present invention provides a PBFDO / Ti3C2T X A self-supporting film, wherein the self-supporting film is composed of PBFDO and Ti3C2T x Composite, Ti3C2T x The mass percentage of the polyol in the PBFDO solution is 1%-20%.

[0008] Furthermore, the Ti3C2T X The mass percentage of the polyol in the PBFDO solution is 5%-10%.

[0009] On the other hand, the present invention provides a PBFDO / Ti3C2T X A method for preparing a self-supporting film, comprising:

[0010] (1) Chemically etch Ti3AlC2 to obtain Ti3C2T X The multilayer material is prepared as an aqueous dispersion;

[0011] (2) The Ti3C2T prepared in step 1 X PBFDO solution was added to the aqueous dispersion, mixed, vacuum filtered and dried to obtain PBFDO / Ti3C2T X Composite film;

[0012] (3) PBFDO / Ti3C2T prepared in step 2 X Composite film peeling to obtain PBFDO / Ti3C2T X Self-supporting film.

[0013] Furthermore, in the step (1), the purity of Ti3AlC2 is greater than 98%, 300-400 mesh; the reaction conditions of chemical etching are oil bath heating, reaction temperature is 40-55°C, and reaction time is 24h.

[0014] Furthermore, the step (1) further comprises chemically etching the multilayer Ti3C2T X The suspension was precipitated and vacuum dried to obtain Ti3C2T x Powder, Ti3C2T x The powder is dispersed in deionized water to prepare an aqueous dispersion.

[0015] Furthermore, in the step (1), the vacuum drying reaction conditions are a temperature of 50°C-60°C and a time of 24 hours; and the concentration of the dispersion is a solution of 0.5-5 mg / ml.

[0016] Furthermore, in step (2), Ti3C2T x The mass percentage concentration of the PBFDO solution is 1%-20%; the vacuum drying condition is 50° C.-60° C., 1 to 12 hours.

[0017] Furthermore, in step (3), the peeling condition is to firstly X The composite film is immersed in the DMF solution for 0.5 to 1 min, then peeled off, rinsed with deionized water, and dried at 60° C. for 0.5 to 2 h.

[0018] In another aspect, the present invention provides PBFDO / Ti3C2T X The applications of self-supporting films are in the fields of supercapacitors, batteries, portable electronic devices, and electric vehicles.

[0019] The present invention has the following beneficial effects:

[0020] In the above scheme, the present invention adopts PBFDO composite Ti3C2T x Self-supporting films were prepared, among which Ti3C2Tx has broad application prospects in the field of energy storage due to its large interlayer spacing, good chemical stability, adjustable surface chemical properties, high conductivity and excellent flexibility; PBFDO (polybenzodifurandione), as an emerging conjugated conductive polymer, has high conductivity, excellent air stability, good solubility and solution processability, and coherent charge transport properties;

[0021] In the present invention, Ti3C2Tx is added to the PBFDO solution, and the electrochemical performance of the conductive polymer electrode material is significantly improved or expanded by utilizing the two-dimensional layered structure and abundant hydrophilic functional groups on the surface of Ti3C2Tx.

[0022] The present invention adopts a vacuum filtration method to prepare a self-supporting composite film, avoids the complex preparation process of using a conductive agent and a binder to coat a carbon cloth, has low requirements on reaction equipment, is simple to operate, has mild conditions, has high preparation efficiency, can effectively simplify the preparation process, and is suitable for popularization and application;

[0023] A composite thin film electrode with high cycle stability can be produced by simple physical mixing and vacuum filtration. The electrode has a capacitance retention rate of 117.1% after 50,000 charge and discharge cycles at a current density of 5A·g-1, which ensures good capacitance performance and excellent stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Ti3C2T in the present invention X and a schematic diagram of the chemical structure of PBFDO;

[0025] Figure 2 PBFDO / Ti3C2T in the present invention X Flow chart of the preparation process of the self-supporting film;

[0026] Figure 3 PBFDO / Ti3C2T prepared in Example 2 of the present invention X Self-supporting films;

[0027] Figure 4PBFDO / Ti3C2T prepared in Examples 1-4 and Comparative Examples 1-2 of the present invention X Electrochemical performance diagram of self-supporting films, including PT5, PT 10 PT 15 , PT 20 Representative Examples 1-4; PT0, PT 100 Representative comparative examples 1-2;

[0028] Figure 5 PBFDO / Ti3C2T prepared in Example 2 of the present invention X Cyclic stability test diagram of free-standing film and comparative example 1PBFDO. DETAILED DESCRIPTION

[0029] In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments. However, the present invention is by no means limited to these examples. The following is only a preferred embodiment of the present invention, which is only used to explain the present invention and cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

[0030] Unless otherwise specified, the components used in the present invention are all commercially available products, and the PBFDO used in the present invention is purchased from Dongguan Fuan Optoelectronics Technology Co., Ltd. The experimental test conditions are not specifically specified and are all conventional technical operations in the art.

[0031] In view of the problems in the prior art that the preparation method of polymer electrode materials is complex and the stability is poor, the present invention provides a PBFDO / Ti3C2T X Self-supporting film and preparation method and application thereof.

[0032] Example

[0033] PBFDO / Ti3C2T X The method for preparing a self-supporting film comprises the following steps:

[0034] 1) Mix 1g LiF with 10ml 9M HCl and etch 1g Ti3AlC2 for 24h to obtain multilayer Ti3C2T X Suspension;

[0035] 2) Multilayer Ti3C2T X The suspension was washed by centrifugation with deionized water until the pH of the supernatant was > 6, and Ti3C2T X precipitation;

[0036] 3) Ti3C2T XThe precipitate was vacuum dried at 60 °C for 24 h to obtain multilayer Ti3C2T X powder;

[0037] 4) Multilayer Ti3C2T X The powder was dispersed in deionized water to a concentration of 5 mg ml -1 The solution was ultrasonicated for 1 h at a power of 200-650 W and centrifuged at 3000 rpm for 30 min to collect the few-layer Ti3C2T X Solution;

[0038] 5) 10 mg ml -1 The PBFDO stock solution was diluted with deionized water to 1 mg ml -1 PBFDO;

[0039] 6) The Ti3C2T prepared in step 4 X The solution was added to 1 mg ml -1 PBFDO was mixed evenly, vacuum filtered, and then vacuum dried at 60 °C for 12 h.

[0040] 7) The dried PBFDO / Ti3C2T X The self-supporting film was immersed in DMF for 0.5-1 min, and the self-supporting film and the filter membrane substrate were peeled off to obtain the self-supporting PBFDO / Ti3C2T X The self-supporting film was rinsed with deionized water and then dried at 60 °C for 0.5 h to prepare PBFDO / Ti3C2T X Self-supporting film.

[0041] In step (6) of Example 1-4, Ti3C2T X The dosage of components is shown in Table 1:

[0042] Table 1

[0043]

[0044] like Figure 1 As shown, the Ti3C2T X and a schematic diagram of the chemical structure of PBFDO; Figure 2 PBFDO / Ti3C2T in the present invention X Flow chart of the preparation process of the self-supporting film; Figure 3 PBFDO / Ti3C2T prepared in Example 2 of the present invention X Self-supporting film.

[0045] The inventors have prepared PBFDO / Ti3C2T XThe beneficial effects achieved by the self-supporting films are X Electrochemical testing of free-standing films.

[0046] The reaction conditions of the electrochemical test are as follows: the reference electrode is Ag / AgCl electrode, the counter electrode is platinum electrode, and the working electrode is self-supporting PBFDO / Ti3C2T X Composite electrode, electrolyte is H2SO4, molar concentration is 1 mol L -1 , potential window is -0.2~1V, scan rate is 5, 10, 20, 50, 100mV / s, current density is 0.5, 1, 2, 5, 8, 10Ag -1 The frequency of AC impedance was 0.01Hz~100kHz, and cyclic voltammetry and chronopotentiometry were used to measure the PBFDO / Ti3C2T X Self-supporting film capacitance value and cycle stability test.

[0047] like Figure 4 As shown, the PBFDO / Ti3C2T prepared in Example 2 of the present invention X Self-supporting film (PT 10 ) shows the electrochemical performance diagram, which can produce the highest mass specific capacitance of 253.3F g -1 .

[0048] like Figure 5 As shown, the self-supporting thin film electrode prepared in Example 2 of the present invention is -1 After 50,000 charge and discharge cycles at a current density of , the capacitance retention rate is 117.1%, which not only ensures good capacitance performance but also has excellent stability.

[0049] In order to further illustrate the beneficial effects of the present invention, the inventor takes Example 2 as an example and sets up the following comparative example for further explanation.

[0050] Table 2

[0051]

[0052]

[0053] The inventors used the same electrochemical experimental test conditions to measure the capacitance and cycle stability of the films prepared in the above comparative examples 1-7. The specific performance data are shown in Table 3:

[0054] Table 3

[0055] Serial number <![CDATA[Specificcapacitance(Fg -1 )]]> Cyclingstability Comparative Example 1 204.2 <![CDATA[79% / 5Ag -1 10000]]> Comparative Example 2 10 <![CDATA[83% / 1Ag -1 4000]]> Comparative Example 3 210.6 <![CDATA[85% / 1Ag -1 1000]]> Comparative Example 4 198.4 <![CDATA[83% / 1Ag -1 4000]]> Comparative Example 5 134.5 <![CDATA[113% / 10Ag -1 30000]]> Comparative Example 6 148.2 <![CDATA[95% / 5Ag -1 10000]]>

[0056] It can be seen from the data in Table 3 that under the same experimental conditions, the PBFDO / Ti3C2T X Self-supporting film (PT 10 ) At the same time, it has a higher mass specific capacitance and high capacitance stability after discharge cycles. It provides a new idea for supercapacitor electrode materials with high capacitance performance, and is applied to portable electronic devices, electric vehicles and other fields. The present invention has broad application prospects and market potential.

[0057] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A PBFDO / Ti3C2T X A self-supporting film, characterized in that The free-standing film is composed of PBFDO and Ti3C2T X Composite, Ti3C2T X The mass percentage of the polyol in the PBFDO solution is 1%-20%.

2. The PBFDO / Ti3C2T3 according to claim 1 X A self-supporting film, characterized in that The Ti3C2T X The mass percentage of the polyol in the PBFDO solution is 5%-10%.

3. PBFDO / Ti3C2T as claimed in claim 1 X The method for preparing a self-supporting film is characterized in that: include: (1) Chemically etch Ti3AlC2 to obtain Ti3C2T X The multilayer material is prepared as an aqueous dispersion; (2) Add the PBFDO solution to the Ti3C2Tx aqueous dispersion prepared in step 1, mix, vacuum filter, and dry to obtain PBFDO / Ti3C2Tx X Composite film; (3) PBFDO / Ti3C2T prepared in step 2 X Composite film peeling to obtain PBFDO / Ti3C2T X Self-supporting film.

4. The PBFDO / Ti3C2T3 according to claim 3 X A self-supporting film, characterized in that In the step (1), the purity of Ti3AlC2 is greater than 98%, 300-400 mesh; the reaction conditions of chemical etching are oil bath heating, reaction temperature is 40-55°C, and reaction time is 24h.

5. The PBFDO / Ti3C2T3 according to claim 3 X A self-supporting film, characterized in that The step (1) further comprises chemically etching the multilayer Ti3C2T X The suspension was precipitated and vacuum dried to obtain Ti3C2T x Powder, Ti3C2T x The powder is dispersed in deionized water to prepare an aqueous dispersion.

6. The PBFDO / Ti3C2T3 according to claim 5 X A self-supporting film, characterized in that In the step (1), the reaction conditions for vacuum drying are a temperature of 50° C.-60° C. and a time of 24 hours; and the concentration of the dispersion is a solution of 0.5 to 5 mg / ml.

7. The PBFDO / Ti3C2T3 according to claim 3 X A self-supporting film, characterized in that In the step (2), Ti3C2T x The mass percentage concentration of the PBFDO solution is 1%-20%; the vacuum drying condition is 50° C.-60° C., 1 to 12 hours.

8. The PBFDO / Ti3C2T3 according to claim 3 X A self-supporting film, characterized in that In the step (3), the peeling condition is to firstly X The composite film is immersed in the DMF solution for 0.5 to 1 min, then peeled off, rinsed with deionized water, and dried at 60° C. for 0.5 to 2 h.

9. The PBFDO / Ti3C2T3 according to claim 1 X The use of a self-supporting film, characterized in that Applied in supercapacitors, batteries, portable electronic devices, and electric vehicles.

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