CN114031870B - Proton exchange membrane and preparation method and application thereof - Google Patents

Abstract

The invention belongs to the technical field of battery materials, and discloses a proton exchange membrane and a preparation method and application thereof. The proton exchange membrane comprises a composite material and a fluorine-containing polymer; the composite material is prepared by loading titanium dioxide nanowires on MXene-Ti ₃ C ₂ The surface of the composite is coated with a fluoropolymer. The invention uniformly loads the one-dimensional titanium dioxide nanowire material on the two-dimensional layered nano carbide MXene-Ti in an electrostatic self-assembly mode ₃ C ₂ The surface of the proton exchange membrane is coated with fluorine-containing polymer to form a proton transmission channel, so that the proton transmission path is shortened, the water retention of the proton membrane is improved, and the conductivity and the dimensional stability of the proton exchange membrane are obviously improved.

Description

A kind of proton exchange membrane and its preparation method and application

technical field

The invention belongs to the technical field of battery materials, and in particular relates to a proton exchange membrane and its preparation method and application.

Background technique

A fuel cell (FuelCell) is a power generation device that can directly convert chemical energy into electrical energy. Hydrogen is oxidized into protons at the anode, and the protons are transported to the cathode through the proton exchange membrane and combined with oxygen to be reduced into water. Fuel cells have the advantages of high power generation efficiency and less environmental pollution.

Proton exchange membrane is the core component of the fuel cell, its electrical conductivity and dimensional stability are of great significance to the efficient and stable operation of the fuel cell. The conductivity and dimensional stability of the proton exchange membranes that have been developed so far cannot be balanced at the same time. For example, the swelling rate of existing proton exchange membranes generally exceeds 12%, indicating that the dimensional stability of the proton exchange membrane is poor, which is not conducive to the normal use of fuel cells. The proton conductivity of existing proton exchange membranes generally does not exceed 40 mS/cm at 30°C.

Therefore, there is an urgent need to provide a proton exchange membrane, which has both high electrical conductivity and dimensional stability, and further improving the thermal stability of the proton exchange membrane is more conducive to the development and application of fuel cells.

Contents of the invention

The present invention aims to solve at least one of the technical problems in the above-mentioned prior art. For this reason, the present invention proposes a proton exchange membrane and its preparation method and application. The proton exchange membrane of the present invention has the characteristics of high electrical conductivity and dimensional stability, and the swelling rate for measuring dimensional stability is lower than 10%. , the proton conductivity at 30°C exceeds 42mS/cm, even as high as 50mS/cm.

The inventive concept of the present invention: two-dimensional layered nano-carbide MXene-Ti ₃ C ₂ (MXene represents a two-dimensional material) is a material with a graphene-like structure, which can be made of ternary layered MAX phase ceramics Ti ₃ AlC ₂ The powder is obtained by selective corrosion. The two-dimensional layered nanocarbide MXene-Ti ₃ C ₂ has a large area ratio and hydrophilicity; the one-dimensional titanium dioxide nanowire has a large aspect ratio and a large number of hydrophilicity on the surface. Aqueous hydroxyl groups. In the present invention, the one-dimensional titanium dioxide nanowire material is evenly loaded on the surface of the two-dimensional layered nano-carbide MXene-Ti ₃ C ₂ through electrostatic self-assembly, and then coated with fluorine-containing polymer together, in the formed proton exchange membrane The proton transport channel is constructed, the proton transport path is shortened, and the water retention of the proton membrane is increased. The proton conductivity and dimensional stability of the proton exchange membrane are significantly improved.

A first aspect of the invention provides a proton exchange membrane.

Specifically, a proton exchange membrane includes a composite material and a fluoropolymer; the composite material is titanium dioxide nanowires supported on the surface of MXene-Ti ₃ C ₂ , and the composite material is coated with a fluoropolymer.

Preferably, the fluorine-containing polymer is selected from a copolymer of polytetrafluoroethylene and perfluoro-3,6-diepoxy-4-methyl-7-decene-sulfuric acid (Nafion for short).

Preferably, the mass ratio of the fluoropolymer, MXene-Ti ₃ C ₂ , and titanium dioxide nanowires is (100-500):(3-20):1; further preferably, the fluoropolymer, MXene The mass ratio of -Ti ₃ C ₂ to titanium dioxide nanowires is (110-425):(5-16):1.

The second aspect of the present invention provides a method for preparing a proton exchange membrane.

Concrete, a kind of preparation method of proton exchange membrane, comprises the following steps:

Preparation of MXene-Ti ₃ C ₂ : Mix acid and fluorine salt, then add Ti ₃ AlC ₂ , react, collect bottom product, then ultrasonic and centrifuge, collect supernatant, which contains MXene-Ti ₃ C ₂ ;

Preparation of titanium dioxide nanowires: dissolving titanium dioxide in lye, dispersing, then carrying out hydrothermal reaction, purifying, and preparing titanium dioxide nanowires;

Preparation of composite material: mix cationic surfactant with solvent, then add titanium dioxide nanowires, stir and mix, then add dropwise the supernatant liquid containing MXene-Ti ₃ C ₂ , and then purify to prepare composite material;

The composite material is mixed with a solvent to obtain a composite material mixture, and then the composite material mixture is dropped into a fluoropolymer solution and mixed to obtain a casting solution, and the casting solution is poured on a carrier, dried, and prepared Obtain the proton exchange membrane.

Preferably, during the preparation of the MXene-Ti ₃ C ₂ , the acid is hydrochloric acid.

Preferably, the concentration of the hydrochloric acid is 8-15mol/L; further preferably, the concentration of the hydrochloric acid is 9-12mol/L.

Preferably, the acid, fluorine salt, and Ti ₃ AlC ₂ are used in an amount ratio of 10mL: (0.6-1.5) g: (0.5-1.0) g; further preferably, the acid, fluorine salt, Ti ₃ AlC ₂ The dosage ratio is 10mL: (0.8-1.2) g: (0.5-0.9) g.

Preferably, the Ti ₃ AlC ₂ is ternary layered MAX phase ceramic Ti ₃ AlC ₂ .

Preferably, in the preparation process of the MXene-Ti ₃ C ₂ , the fluorine salt is LiF or NaF.

Preferably, during the preparation of the MXene-Ti ₃ C ₂ , the reaction temperature is 30-40°C, and the reaction time is 24-48 hours; further preferably, the reaction temperature is 33- 38°C, the reaction time is 36-48 hours.

Preferably, in the preparation process of the MXene-Ti ₃ C ₂ , the bottom product is centrifugally washed to neutrality, and the product obtained after washing is dispersed in water, and nitrogen or argon gas is blown in for ultrasonic treatment.

Preferably, during the preparation of the MXene-Ti ₃ C ₂ , the supernatant liquid is stored at a temperature of 0-7°C.

Preferably, during the preparation of the titanium dioxide nanowires, the reaction temperature of the hydrothermal reaction is 140-190°C; the reaction time is 18-36 hours; further preferably, the reaction temperature of the hydrothermal reaction 150-160°C; the reaction time is 20-24 hours.

Preferably, in the preparation process of the titanium dioxide nanowires, the alkali solution is selected from sodium hydroxide solution or potassium hydroxide solution.

Further preferably, the concentration of the sodium hydroxide solution or potassium hydroxide solution is 6-14 mol/L, more preferably 8-12 mol/L.

Preferably, in the preparation process of the titanium dioxide nanowires, after the hydrothermal reaction is completed, the specific process of the purification is: washing the product after the hydrothermal reaction with deionized water to neutrality (pH=7), and then Then, the bottom precipitate was collected by high-speed centrifugation, and then the bottom precipitate was freeze-dried to finally obtain a one-dimensional titanium dioxide nanowire.

Preferably, in the preparation process of the composite material, the cationic surfactant is selected from cetyltrimethylammonium bromide, octadecylaminotrimethylammonium chloride, octadecyltrimethylammonium bromide At least one of ammonium, cetylaminotrimethylammonium chloride or dodecyltrimethylammonium chloride (bromide).

Preferably, in the mixture formed after the cationic surfactant is mixed with the solvent, the mass concentration of the cationic surfactant is 0.05-1%, preferably 0.05-0.5%.

Preferably, titanium dioxide nanowires are added to the mixture formed by mixing the cationic surfactant and the solvent, and the concentration of the titanium dioxide nanowires in the mixture is 0.05-0.8 mg/mL; more preferably 0.05-0.5 mg/mL.

Preferably, the supernatant liquid containing MXene-Ti ₃ C ₂ is diluted before use to a concentration of 0.1-1.2 mg/mL of MXene-Ti ₃ C ₂ ; preferably 0.1-1 mg/mL.

Preferably, the mass ratio of the titanium dioxide nanowires to the MXene-Ti ₃ C ₂ in the supernatant liquid is 1:(3-15); the preferred mass ratio is 1:(5-10).

Preferably, during the preparation of the composite material, the solvent is water, preferably deionized water. The surface of the two-dimensional MXene-Ti ₃ C ₂ material is negatively charged, while the surface of the one-dimensional titanium dioxide nanowire material is uncharged (or the positive charge is very small), and the one-dimensional titanium dioxide nanowire material is charged by cationic surfactant. Modification can make the surface of one-dimensional titanium dioxide nanowires positively charged. Therefore, when the positively charged one-dimensional titanium dioxide nanowire meets the negatively charged two-dimensional MXene-Ti ₃ C ₂ material, due to the electrostatic attraction between the two, the one-dimensional titanium dioxide nanowire will quickly adsorb to the On the two-dimensional MXene-Ti ₃ C ₂ material, the process is electrostatic self-assembly.

Preferably, during the preparation of the composite material, the purification includes centrifugation, washing and freeze-drying.

Preferably, when the composite material is mixed with a solvent, the solvent is an organic solvent, preferably the organic solvent is N,N-dimethylacetamide, dimethyl sulfoxide or N,N-dimethylformamide at least one.

Preferably, the solvent in the fluoropolymer solution is at least one of N,N-dimethylacetamide, dimethylsulfoxide or N,N-dimethylformamide.

Preferably, the mass ratio of the fluoropolymer to the solvent in the fluoropolymer solution is 1:(3-85), more preferably 1:(3-80).

Preferably, the mass ratio of the composite material to the fluoropolymer is 1:(5-120), more preferably 1:(10-100).

Preferably, the solvent mixed with the composite material and the solvent in the fluoropolymer solution are the same solvent.

Preferably, the carrier is a plastic mold or a glass plate.

Preferably, the drying temperature is 60-160°C, and the drying time is 10-24 hours; further preferably, the drying temperature is 60-150°C, and the drying time is 12-24 hours.

Preferably, after the proton exchange membrane is prepared, the proton exchange membrane is sequentially soaked and washed with hydrogen peroxide solution, sulfuric acid solution and deionized water, and finally dried at 50-60°C.

The third aspect of the present invention provides the use of the above-mentioned proton exchange membrane.

A battery comprising the proton exchange membrane of the present invention.

Preferably, the battery is a fuel cell.

Compared with the prior art, the beneficial effects of the present invention are as follows:

(1) In the present invention, the one-dimensional titanium dioxide nanowire material is evenly loaded on the surface of the two-dimensional layered nanocarbide MXene-Ti ₃ C ₂ through electrostatic self-assembly to form a composite material, and the composite material is coated with a fluoropolymer. The proton transport channel is constructed in the formed proton exchange membrane, which shortens the path of proton transport and increases the water retention of the proton exchange membrane. ) and dimensional stability (swelling rate of the proton exchange membrane is less than 10%) are significantly improved.

(2) The preparation process of the proton exchange membrane of the present invention consumes less energy and has a warm condition, and is suitable for large-scale production.

Description of drawings

Fig. 1 is the SEM (scanning electron microscope) figure of the MXene-Ti that step (1) in the embodiment of the present invention 1 makes ₃ C ₂ ;

Fig. 2 is the TEM (transmission electron microscope) figure of the titania nanowire that step (2) in the embodiment of the present invention 1 makes;

Fig. 3 is the SEM figure of the composite material that step (3) in the embodiment of the present invention 1 makes;

Fig. 4 is the sectional view of the proton exchange membrane that step (4) in the embodiment of the present invention 1 makes;

Fig. 5 is the thermal stability test result figure of the proton exchange membrane that the embodiment of the present invention 1-3 makes and the Nafion 115 commercialization proton membrane in the comparative example;

Fig. 6 is the swelling ratio test result figure of the proton exchange membrane that the embodiment of the present invention 1-3 makes and the Nafion 115 commercialization proton membrane in the comparative example;

Fig. 7 is a graph showing the proton conductivity test results of the proton exchange membrane prepared in Examples 1-3 of the present invention and the Nafion 115 commercial proton membrane in the comparative example.

Detailed ways

In order to make those skilled in the art understand the technical solution of the present invention more clearly, the following examples are listed for illustration. It should be pointed out that the following examples do not limit the protection scope of the present invention.

Unless otherwise specified, the raw materials, reagents or devices used in the following examples can be obtained from conventional commercial channels, or can be obtained by existing known methods.

Embodiment 1: the preparation of proton exchange membrane

A proton exchange membrane, comprising a composite material and a fluoropolymer; the composite material is that titanium dioxide nanowires are supported on the surface of MXene-Ti ₃ C ₂ , the composite material is coated by a fluoropolymer, and the fluoropolymer is polytetrafluoroethylene And perfluoro-3,6-diepoxy-4-methyl-7-decene-sulfuric acid copolymer (referred to as Nafion).

The mass ratio of fluorine-containing polymer, MXene-Ti ₃ C ₂ , and titanium dioxide nanowires is 120:5:1.

A method for preparing a proton exchange membrane, comprising the following steps:

(1) Preparation of MXene-Ti ₃ C ₂ : Pour 10 mL of 9mol/L hydrochloric acid into a plastic container containing 0.8 g LiF and stir evenly, then add 0.5 g of ternary layered MAX phase ceramic Ti ₃ AlC ₂ powder, React at a constant temperature of 35°C for 48 hours, collect the bottom product, centrifuge and wash the bottom product to neutrality, and disperse the washed product in water, blow nitrogen into it for ultrasonic treatment for 1 hour, collect the upper layer, which contains MXene-Ti _{3 C2} ;

(2) Preparation of titanium dioxide nanowires: Dissolve 1g of titanium dioxide powder in 9mol/L NaOH solution, use mechanical stirring and ultrasonic treatment to uniformly disperse titanium dioxide to obtain a mixture, and then transfer the mixture to a PTFE (polytetrafluoroethylene) In a lined autoclave, seal it and put it in a high-temperature drying oven at 170°C for hydrothermal reaction, the reaction time is 20 hours, then wash it with deionized water until the pH of the supernatant is 7, and then collect it by centrifugation The bottom precipitate is then freeze-dried to obtain a one-dimensional titanium dioxide nanowire;

(3) preparation of composite material: 0.05g cetyltrimethylammonium bromide is added in 100g deionized water, is stirred to dissolve, obtains the cetyltrimethylammonium bromide solution that mass concentration is 0.05%, then Add 5 mg of titanium dioxide nanowires prepared in step (2), stir and mix to obtain a 0.05 mg/mL solution of titanium dioxide nanowires modified by a cationic surfactant (hexadecyltrimethylammonium bromide). Slowly drop 20mL (0.05mg/mL) of titanium dioxide nanowire solution modified by cationic surfactant (hexadecyltrimethylammonium bromide) into 10mL (0.5mg/mL) of step (1). In the supernatant liquid containing MXene-Ti ₃ C ₂ , the resulting product was collected after centrifugation, washing and freeze-drying to obtain a composite material (titanium dioxide nanowires supported on the surface of MXene-Ti ₃ C ₂ );

(4) Add 0.5g of the composite material prepared in step (3) to 50g of N,N-dimethylformamide and disperse evenly to obtain a composite material mixture, then drop the composite material mixture into the solution of fluoropolymer (10g Nafion and 50g N,N-dimethylformamide are mixed to form a solution of fluoropolymer), fully mixed uniformly to obtain a casting solution, pour the casting solution into a tetrafluoroethylene mold, and heat at 80°C Dried under the sun for 24 hours to prepare a proton exchange membrane, then soaked and washed the proton exchange membrane with a mass concentration of 3% hydrogen peroxide solution, 1mol/L sulfuric acid solution, and deionized water for 1 hour, and finally put it in a 60°C blast drying oven to dry .

Fig. 1 is the SEM picture of the MXene-Ti _{3 C 2} that step (1) in the embodiment of the present invention makes; As can be seen from Fig. 1, the MXene-Ti ₃ C that step (1) makes has two-dimensional layered structure features.

Figure 2 is a TEM image of the titanium dioxide nanowires prepared in step (2) of Example 1 of the present invention; as can be seen from Figure 2, the titanium dioxide nanowires produced in step (2) have one-dimensional linear characteristics.

Fig. 3 is the SEM picture of the composite material that step (3) in the embodiment of the present invention 1 makes; As can be seen from Fig. 3, in the composite material that step (3) makes, titania nanowire is supported on MXene-Ti ₃ C ₂ surfaces.

4 is a cross-sectional view of the proton exchange membrane prepared in step (4) in Example 1 of the present invention. It can be seen from Figure 4 that the composite material (titanium dioxide nanowires loaded on the surface of MXene-Ti ₃ C ₂ ) is coated by Nafion, the composite material is uniformly dispersed in Nafion, and there is no phenomenon of composite material agglomeration, the composite material and Nafion Have good interface compatibility.

Embodiment 2: the preparation of proton exchange membrane

A proton exchange membrane, comprising a composite material and a fluoropolymer; the composite material is that titanium dioxide nanowires are supported on the surface of MXene-Ti ₃ C ₂ , the composite material is coated by a fluoropolymer, and the fluoropolymer is polytetrafluoroethylene And perfluoro-3,6-diepoxy-4-methyl-7-decene-sulfuric acid copolymer (referred to as Nafion).

The mass ratio of fluoropolymer, MXene-Ti ₃ C ₂ , and titanium dioxide nanowires is 425:16:1.

A method for preparing a proton exchange membrane, comprising the following steps:

(1) Preparation _of MXene- _Ti3C2 : Pour 20mL of 10mol/L hydrochloric acid into a plastic _container containing 1.8gLiF and stir evenly, then add 1.2g of ternary layered MAX phase ceramic _Ti3AlC2 powder, React at a constant temperature of 35°C for 48 hours, collect the bottom product, centrifuge and wash the bottom product to neutrality, disperse the washed product in water, blow nitrogen into it for ultrasonic treatment for 1.2 hours, collect the upper layer, which contains MXene-Ti _{3 C2} ;

(2) Preparation of titanium dioxide nanowires: Dissolve 1g of titanium dioxide powder in 10mol/L NaOH solution, use mechanical stirring and ultrasonic treatment to uniformly disperse titanium dioxide to obtain a mixture, and then transfer the mixture to a PTFE (polytetrafluoroethylene) In a lined autoclave, seal it and put it in a high-temperature drying oven at 160°C for hydrothermal reaction. The reaction time is 24 hours, then wash with deionized water until the pH of the supernatant is 7, and then collect it by centrifugation The bottom precipitate is then freeze-dried to obtain a one-dimensional titanium dioxide nanowire;

(3) Preparation of composite material: 0.1g octadecylaminotrimethylammonium chloride is added to 100g deionized water, stirred to dissolve, and obtaining mass concentration is 0.1% octadecylaminotrimethylammonium chloride solution, then adding step (2) The prepared 10 mg titanium dioxide nanowires were stirred and mixed to obtain a 0.1 mg/mL solution of titanium dioxide nanowires modified by a cationic surfactant (octadecylaminotrimethylammonium chloride). 50mL (0.1mg/mL) of titanium dioxide nanowire solution modified by cationic surfactant (octadecylaminotrimethylammonium chloride) was slowly dropped into 80mL (1mg/mL) of MXene-Ti In the supernatant of ₃ C ₂ , the resulting product was collected after centrifugation, washing and freeze-drying to obtain a composite material (titanium dioxide nanowires supported on the surface of MXene-Ti ₃ C ₂ );

(4) Add the composite material that 1g step (3) makes to 75g N, and disperse evenly in the N-dimethylacetamide, make composite material mixture, then the composite material mixture is dripped into the solution of fluoropolymer ( 25g Nafion mixed with 75g N,N-dimethylacetamide to form a fluoropolymer solution), fully mixed uniformly to prepare a casting solution, pour the casting solution into a tetrafluoroethylene mold, and heat the solution at 120°C Dry for 24 hours to prepare a proton exchange membrane, then soak and wash the proton exchange membrane with a mass concentration of 3% hydrogen peroxide solution, 1mol/L sulfuric acid solution, and deionized water for 1 hour, and finally put it into a 60°C blast drying oven for drying.

Embodiment 3: the preparation of proton exchange membrane

A proton exchange membrane, comprising a composite material and a fluoropolymer; the composite material is that titanium dioxide nanowires are supported on the surface of MXene-Ti ₃ C ₂ , the composite material is coated by a fluoropolymer, and the fluoropolymer is polytetrafluoroethylene And perfluoro-3,6-diepoxy-4-methyl-7-decene-sulfuric acid copolymer (referred to as Nafion).

The mass ratio of fluoropolymer, MXene-Ti ₃ C ₂ , and titanium dioxide nanowires is 110:10:1.

A method for preparing a proton exchange membrane, comprising the following steps:

(1) Preparation _of MXene- _Ti3C2 : Pour 30mL of 12mol/L hydrochloric acid into _a plastic container containing 3.6gLiF and stir evenly, then add 2.7g of ternary layered MAX phase ceramic _Ti3AlC2 powder, React at a constant temperature of 35°C for 48 hours, collect the bottom product, centrifuge and wash the bottom product to neutrality, and disperse the washed product in water, blow nitrogen into it for ultrasonic treatment for 1.5 hours, collect the upper layer, which contains MXene-Ti _{3 C2} ;

(2) Preparation of titanium dioxide nanowires: Dissolve 1g of titanium dioxide powder in 12mol/L NaOH solution, use mechanical stirring and ultrasonic treatment to uniformly disperse titanium dioxide to obtain a mixture, and then transfer the mixture to a PTFE (polytetrafluoroethylene) In a lined autoclave, seal it and place it in a high-temperature drying oven at 180°C for hydrothermal reaction, the reaction time is 36 hours, then wash it with deionized water until the pH of the supernatant is 7, and then collect it by centrifugation The bottom precipitate is then freeze-dried to obtain a one-dimensional titanium dioxide nanowire;

(3) Preparation of composite material: 0.5g octadecyltrimethylammonium bromide is added in 100g deionized water, stirred to dissolving, obtaining mass concentration is 0.5% octadecyltrimethylammonium bromide solution, then Add 50 mg of titanium dioxide nanowires prepared in step (2), stir and mix to obtain a 0.5 mg/mL solution of titanium dioxide nanowires modified by a cationic surfactant (octadecyltrimethylammonium bromide). Slowly drop 20mL (0.5mg/mL) of titanium dioxide nanowire solution modified by cationic surfactant (octadecyltrimethylammonium bromide) into 100mL (1mg/mL) prepared in step (1). In the supernatant containing MXene-Ti ₃ C ₂ , the resulting product was collected after centrifugation, washing and freeze-drying to obtain a composite material (titanium dioxide nanowires supported on the surface of MXene-Ti ₃ C ₂ );

(4) the composite material that 1.5g step (3) is made is added in 150g dimethyl sulfoxide and disperses uniformly, makes composite material mixture, then the solution (15g Nafion and 15g Nafion and 150g of dimethyl sulfoxide mixed to form a fluorine-containing polymer solution), fully mixed to obtain a casting solution, pour the casting solution into a tetrafluoroethylene mold, and dry at 140°C for 24 hours to obtain a proton Exchange the membrane, then soak and wash the proton exchange membrane with a mass concentration of 3% hydrogen peroxide solution, 1mol/L sulfuric acid solution, and deionized water for 1 hour, and finally put it into a 60°C blast drying oven for drying.

comparative example

The comparative example is Nafion 115 commercial proton membrane.

Product Effect Test

1. Thermal stability test of proton exchange membrane

The thermal stability of the proton exchange membrane prepared in Examples 1-3 and the Nafion 115 commercial proton membrane in the comparative example were tested under the same conditions, and the results are shown in FIG. 5 .

Fig. 5 is the thermal stability test result figure of the proton exchange membrane that the embodiment of the present invention 1-3 makes and the Nafion 115 commercialization proton membrane in comparative example; From Fig. 5 (Fig. 5 abscissa " Temperature " represents temperature, vertical Coordinate "Weight" represents weight) It can be seen that within the range of 100-400°C, the reduction in the weight of the proton exchange membrane prepared in Example 1-3 of the present invention is less than that of the comparative example, indicating that the proton exchange membrane produced in Example 1-3 of the present invention The thermal stability of the obtained proton exchange membrane is obviously better than that of the Nafion115 commercialized proton membrane in the comparative example.

2. Dimensional stability test of proton exchange membrane

Take the proton exchange membrane prepared in Examples 1-3 and the Nafion 115 commercialized proton membrane in the comparative example, test their swelling rate under the same conditions, the smaller the swelling rate, the more stable the dimensional stability, the results are shown in Figure 6 Show.

Swelling rate test conditions are as follows: cut the proton exchange membrane into a rectangular strip with a length of 5 cm and a width of 1 cm, soak it in deionized water at 80°C for 8 hours, then take out the proton exchange membrane, and gently wipe off the water on the surface of the proton exchange membrane with filter paper , followed by rapid measurement of the length A ₁ of the proton exchange membrane. The formula for calculating the swelling rate is: swelling rate=[(A ₁ -5)/5]*100%.

Fig. 6 is the swelling rate test result figure of the proton exchange membrane that the embodiment of the present invention 1-3 makes and the Nafion 115 commercialized proton membrane in the comparative example; As can be seen from Fig. 6, the embodiment of the present invention 1-3 makes The swelling rate of the proton exchange membrane of the present invention is less than 10%, obviously less than the swelling rate 12% of Nafion 115 commercialization proton membrane in the comparative example, shows that the dimensional stability of the proton exchange membrane that the embodiment of the present invention 1-3 makes is good, especially The swelling rate of the proton exchange membrane prepared in Example 3 is less than 6%, and the dimensional stability is the best.

3. Proton exchange membrane proton conductivity test

Get the proton exchange membrane that embodiment 1-3 makes and the Nafion 115 commercialized proton membrane in comparative example, test its proton conductivity under the same condition (100% relative humidity, 30-90 ℃), the result is shown in Figure 7 Show.

Fig. 7 is a graph showing the proton conductivity test results of the proton exchange membrane prepared in Examples 1-3 of the present invention and the Nafion 115 commercial proton membrane in the comparative example. As can be seen from Figure 7, at 100% relative humidity, under the condition of 30-90°C, the proton conductivity of the proton exchange membrane prepared in Examples 1-3 of the present invention is significantly better than that of Nafion 115 commercial proton membrane in the comparative example proton conductivity. For example, at 60° C., the proton conductivities of the proton exchange membranes prepared in Examples 1-3 are 77 mS/cm, 75 mS/cm, 84 mS/cm, and 64 mS/cm, respectively. At 30°C, the proton conductivity of the proton exchange membrane prepared in Examples 1-3 exceeds 42mS/cm, even as high as 50mS/cm, and the proton conductivity of the comparative example is less than 40mS/cm.

Claims (9)

1. a proton exchange membrane, is characterized in that, comprises composite material, fluoropolymer; Described composite material is that titanium dioxide nanowire is supported on MXene-Ti ₃ C ₂ surface, and described composite material is covered by described fluoropolymer cladding; The mass ratio of the fluorine-containing polymer, MXene-Ti ₃ C ₂ , and titanium dioxide nanowires is (100-500): (3-20): 1; The swelling rate of the proton exchange membrane is less than 10%; The preparation method of described proton exchange membrane comprises the following steps: Preparation of MXene-Ti ₃ C ₂ : Mix acid and fluorine salt, then add Ti ₃ AlC ₂ , react, collect bottom product, then ultrasonic and centrifuge, collect supernatant, which contains MXene-Ti ₃ C ₂ ; During the preparation of the MXene-Ti ₃ C ₂ , the reaction temperature is 30-40°C, and the reaction time is 24-48 hours; Preparation of titanium dioxide nanowires: dissolving titanium dioxide in lye, dispersing, then carrying out hydrothermal reaction, purifying, and preparing titanium dioxide nanowires; Preparation of the composite material: mixing the cationic surfactant with the solvent, adding titanium dioxide nanowires, stirring and mixing, then adding the supernatant liquid dropwise, and then purifying to obtain the composite material; The composite material is mixed with a solvent to obtain a composite material mixture, and then the composite material mixture is dropped into a fluoropolymer solution and mixed to obtain a casting solution, and the casting solution is poured on a carrier, dried, and prepared Obtain the proton exchange membrane. 2. The proton exchange membrane according to claim 1, wherein the fluoropolymer is selected from polytetrafluoroethylene and perfluoro-3,6-diepoxy-4-methyl-7-decene - Copolymers of sulfuric acid. 3. the preparation method of the proton exchange membrane described in any one of claim 1-2 is characterized in that, comprises the following steps: Preparation of MXene-Ti ₃ C ₂ : Mix acid and fluorine salt, then add Ti ₃ AlC ₂ , react, collect bottom product, then ultrasonic and centrifuge, collect supernatant, which contains MXene-Ti ₃ C ₂ ; During the preparation of the MXene-Ti ₃ C ₂ , the reaction temperature is 30-40°C, and the reaction time is 24-48 hours; Preparation of titanium dioxide nanowires: dissolving titanium dioxide in lye, dispersing, then carrying out hydrothermal reaction, purifying, and preparing titanium dioxide nanowires; Preparation of the composite material: mixing the cationic surfactant with the solvent, adding titanium dioxide nanowires, stirring and mixing, then adding the supernatant liquid dropwise, and then purifying to obtain the composite material; The composite material is mixed with a solvent to obtain a composite material mixture, and then the composite material mixture is dropped into a fluoropolymer solution and mixed to obtain a casting solution, and the casting solution is poured on a carrier, dried, and prepared Obtain the proton exchange membrane. 4. preparation method according to claim 3, is characterized in that, in the preparation of described MXene-Ti ₃ C ₂ , described acid is hydrochloric acid, and the concentration of described hydrochloric acid is 8-15mol/L; Described acid, The dosage ratio of fluorine salt and Ti ₃ AlC ₂ is 10mL: (0.6-1.5) g: (0.5-1.0) g. 5 . The preparation method according to claim 3 , wherein the Ti ₃ AlC ₂ is ternary layered MAX phase ceramic Ti ₃ AlC ₂ . 6. The preparation method according to claim 3, characterized in that, in the preparation of the titanium dioxide nanowires, the reaction temperature of the hydrothermal reaction is 140-190°C; the reaction time of the hydrothermal reaction is 18- 36 hours. 7 . The preparation method according to claim 3 , wherein the mass ratio of the titanium dioxide nanowires to MXene-Ti ₃ C ₂ in the supernatant liquid is 1:(3-15). 8. The preparation method according to claim 3, characterized in that the mass ratio of the composite material to the fluoropolymer is 1: (5-120). 9. A battery, characterized in that it comprises the proton exchange membrane according to any one of claims 1-2.