A multi-fluorinated side chain anion exchange membrane for direct ammonia fuel cells and a method of preparing the same

Abstract

The application belongs to the technical field of ion exchange membranes, and particularly relates to a kind of anion exchange membrane with polyfluorinated side chain and a preparation method thereof, and the steps are as follows: (1) preparation of polyfluorinated acetophenone monomer; (2) preparation of polyaryl-polyfluorinated copolymer; (3) preparation of quaternary ammonium polyaryl-polyfluorinated copolymer; (4) preparation of anion exchange membrane. In the application, F element is introduced by copolymerization to promote microphase separation and further enhance the conductivity of the anion exchange membrane. Moreover, the introduction of fluorine element makes the membrane more hydrophobic, reduces the water absorption and swelling degree of the membrane, and is used in the fields of low-temperature direct ammonia fuel cell and electrolysis of ammonia water, and has good ammonia resistance.

Description

Technical Field

[0001] This invention belongs to the field of fuel cell material technology, and specifically relates to a method for preparing a polyfluorinated side-chain anion exchange membrane. Background Technology

[0002] A fuel cell is a device that converts chemical energy into electrical energy. Based on different reaction principles, fuel cells can be classified into various types, such as proton exchange membrane fuel cells (PEMFCs), alkaline anion exchange membrane fuel cells (AEMFCs), solid oxide fuel cells (SOFCs), and molten carbonate fuel cells (MCFCs). Among alkaline anion exchange membrane fuel cells, the widespread application of hydrogen fuel cells is limited by hydrogen storage and transportation, while methanol fuel cells suffer from carbon emissions. In contrast, ammonia is a carbon-free fuel with high volumetric energy density and easy liquefaction and storage. Low-temperature direct ammonia fuel cells (DAFCs) using liquid ammonia or ammonia gas as fuel have advantages such as rapid start-up and environmental friendliness, and are considered promising new fuel cell technologies in lightweight applications such as drones, bicycles, uninterruptible power supplies (UPS), and mobile power supplies. However, due to the small molecular size of ammonia and its high solubility in water, it easily permeates the anion exchange membrane, posing a serious challenge to the field of low-temperature direct ammonia fuel cells (DAFCs). Ammonia permeation not only reduces fuel utilization but can also impair the long-term stability of the cell. The anion exchange membrane (HEM), as a key component, determines the ammonia permeation capacity of DAFCs. Jung et al. prepared an anion exchange membrane using cross-linked polyethylene porous membrane as a substrate, which suppressed membrane swelling and water absorption, thereby reducing ammonia permeation. However, the conductivity was only 30 mS / cm at 60 °C (H. Jung, Journal of Membrane Science 373(2011)107–111.). Therefore, how to prepare anion exchange membranes with high conductivity and low ammonia permeation is crucial for the commercial application of ammonia fuel cells. Summary of the Invention

[0003] To address the above problems, this invention provides a multi-fluorinated side-chain anion exchange membrane for direct ammonia fuel cells and its preparation method, exhibiting high conductivity and low ammonia permeation. One objective of this invention is to introduce fluorine to increase the membrane's hydrophobicity and reduce its water absorption rate, thereby decreasing ammonia permeation. Another objective is to introduce fluorine to promote microphase separation and ensure good conductivity.

[0004] To achieve the above objectives, the following technical solution is adopted:

[0005] A multi-fluorinated side-chain anion exchange membrane for direct ammonia fuel cells, wherein the anion exchange membrane is a polyarylpiperidine polyfluoropolymer, and its general structural formula is shown below:

[0006]

[0007] Wherein, Ar is any one of the following aryl monomers, or is copolymerized using any two of the following aryl monomers:

[0008]

[0009] Where R is -CF3 or -CH3, 0≤x≤3, 1≤m≤30.

[0010] The preparation method of the above-mentioned polyfluorinated side-chain anion exchange membrane includes the following steps:

[0011] (1) Preparation of polyfluoroacetophenone monomer:

[0012] In the presence of Cs2CO3, Pd2(dba)3 catalyst and BrettPhos ligand, aryl halides and alcohols react at 80-90℃ for 2-5 h to obtain polyfluoroacetophenone monomers.

[0013] (2) Preparation of polyaryl-polyfluorinated copolymers:

[0014] The polyfluoroacetophenone monomer obtained in step (1) was dissolved in dichloromethane along with aryl monomers Ar and 1-methyl-4-piperidinone. Trifluoroacetic acid and trifluoromethanesulfonic acid were added in an ice bath (0-4℃), and the mixture was mechanically stirred (200-1000 r) for 48-72 h. After the reaction was completed, the product was precipitated in an alkaline solution and washed with deionized water until pH=7 to obtain polyaryl-polyfluoropolymer.

[0015] (3) Preparation of quaternized polyaryl-polyfluorinated copolymers:

[0016] The quaternized polyaryl-polyfluorinated copolymer is dissolved in a good solvent, and excess iodomethane is added. The reaction temperature is controlled at 30-60℃ and the reaction time is 24-48h. After the reaction is completed, the reaction solution is added dropwise to diethyl ether or ethyl acetate to precipitate the product. The product is washed with ethyl acetate or diethyl ether and dried to obtain the polyaryl-polyfluorinated copolymer.

[0017] (4) Preparation of anion exchange membranes:

[0018] The quaternized polyaryl-polyfluorinated copolymer was dissolved in a good solvent to obtain a quaternized polyaryl-polyfluorinated copolymer solution with a mass fraction of 2.5-10 wt%. Subsequently, the target anion exchange membrane was prepared by casting at 80-120℃.

[0019] Based on the above technical solutions, preferably, in step (1), the reaction solvent is one of toluene, methyl chloride, or methanol, the reaction atmosphere is an inert atmosphere, and the ratio of aryl halide to reaction solvent is 1-2 mmol: 1 ml.

[0020] Based on the above technical solutions, preferably, in step (1), the aryl halide is one or more of 4-bromoacetophenone, 4-fluoroacetophenone, 4-chloroacetophenone, 2,2,2,4'-tetrafluoroacetophenone, 4'-bromo-2,2,2-trifluoroacetophenone, and 4'-chloro-2,2,2-trifluoroacetophenone.

[0021] Based on the above technical solutions, preferably, in step (1), the alcohol is one or more of trifluoroethanol, pentafluoropropanol, heptafluorobutanol, and 1H,1H-nonafluoro-1-pentanol.

[0022] Based on the above technical solutions, preferably, in step (1), the molar ratio of the aryl halide to the alcohol is 1:(1.1-5).

[0023] Based on the above technical solutions, preferably, in step (1), the molar ratio of the Cs2CO3, Pd2(dba)3 catalyst and BrettPhos ligand to the aryl halide is (1.2-2):(0.4-0.6):(0.01-0.03):1.

[0024] Based on the above technical solutions, preferably, in step (1), after the reaction is completed, the reaction mixture is cooled to room temperature, filtered through a silica gel column with chloroform, and the solvent is removed under reduced pressure to obtain the desired compound as a yellow / colorless oily or solid product.

[0025] Based on the above technical solution, preferably, step (1) is as follows: Cs2CO3, Pd2(dba)3 catalyst and BrettPhos ligand are added to the flask sequentially. Then the flask is evacuated and filled with argon. On this basis, 1.0 ml of anhydrous toluene is added through a syringe and stirred at room temperature for 5 minutes. The solution of aryl halide and alcohol is added to 1.0 ml of toluene and added to the flask through a syringe. Another 1.0 ml of toluene is added to the reaction flask (for rinsing), and the reaction flask is placed in a preheated oil bath at 80-90℃. The reaction mixture is stirred vigorously for 2-5 hours. After the raw materials are completely consumed (monitored by TLC), the reaction mixture is cooled to room temperature, filtered through a silica gel column (230-400 mesh) with chloroform, and the solvent is removed under reduced pressure to obtain the desired compound as a yellow / colorless oily or solid product.

[0026] Based on the above technical solutions, preferably, in step (2), the molar ratio of the aryl monomer, polyfluoroacetophenone monomer and 1-methyl-4-piperidinone is 10:(5~1):(5~9).

[0027] Based on the above technical solution, preferably, in step (2), the molar ratio of the aryl monomer, trifluoroacetic acid and trifluoromethanesulfonic acid is 1:(1-1.5):(5-10).

[0028] Based on the above technical solution, preferably, in step (2), the ratio of the aryl monomer to dichloromethane is 1 mmol:(0.9-1.5) mL.

[0029] Based on the above technical solutions, preferably, in step (2), the alkaline solution is either a saturated potassium carbonate solution or a 1-5 mol / L KOH solution.

[0030] Based on the above technical solutions, preferably, in steps (3) and (4), the good solvent is dimethyl sulfoxide, N,N-dimethylformamide, N-methylpyrrolidone, or N,N-dimethylacetamide.

[0031] Based on the above technical solutions, preferably, in step (3), the molar ratio of the polyaryl-polyfluorinated copolymer and iodomethane is 1:(1-10), and more preferably 1:(3-5).

[0032] Based on the above technical solutions, preferably, in step (3), the mass concentration of the polyaryl-polyfluorinated copolymer in a good solvent is 5-10 wt%.

[0033] Based on the above technical solutions, preferably, in step (4), the casting method is as follows: the quaternized polyaryl-polyfluorinated polyelectrolyte solution is poured onto a clean glass plate and dried in an oven at 80-120℃ for 24-48 hours to obtain the target anion exchange membrane.

[0034] The above-mentioned polyfluorinated side-chain anion exchange membranes are used in ammonia fuel cells (especially low-temperature direct ammonia fuel cells) or in the electrolysis of ammonia water.

[0035] Beneficial effects

[0036] This invention provides a multi-fluorinated side-chain anion exchange membrane for direct ammonia fuel cells and its preparation method. In this invention, by introducing fluorine (F) through copolymerization, microphase separation is promoted, thereby enhancing the conductivity of the anion exchange membrane. Furthermore, the introduction of fluorine makes the membrane more hydrophobic, reducing its water absorption and swelling degree. This results in excellent ammonia barrier performance for applications such as low-temperature direct ammonia fuel cells and ammonia electrolysis. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the preparation process of quaternized polyaryl-polyfluorinated copolymer in polyfluorinated side-chain anion exchange membranes.

[0038] Figure 2 It is 4-(2-2-2-trifluoroethoxy)acetophenone from Example 1. 19 F spectrum.

[0039] Figure 3 This is the 1H NMR spectrum of Example 1.

[0040] Figure 4 This is the SEM image of Example 1. Detailed Implementation

[0041] The following non-limiting embodiments are intended to enable those skilled in the art to more fully understand the present invention, but do not limit the invention in any way.

[0042] Example 1

[0043] A method for preparing a polyfluorinated side-chain anion exchange membrane, such as... Figure 1 As shown, it includes the following steps:

[0044] (1) Preparation of 4-(2-2-2-trifluoroethoxy)acetophenone monomer:

[0045] A double-necked round-bottom flask, dried in an oven, was equipped with a magnetic rotor, a condenser with a top argon balloon at one neck, and a rubber stopper at the other. Cs₂CO₃ (3.02 mmol) (dried under vacuum), Pd₂(dba)₃ (1 mol%) catalyst, and BrettPhos (13.4 mg) ligand were added sequentially to the flask. The flask was then evacuated and repeatedly purged with argon three times. Following this, 1.0 mL of anhydrous toluene was added via syringe, and the mixture was stirred at room temperature for 5 minutes. A solution of 4-fluoroacetophenone (1 mmol) and trifluoroethanol (110 μL) was added to 1.0 mL of toluene via syringe to the flask. Another 1.0 mL of toluene was added to the reaction flask (for rinsing), and the flask was placed in a preheated oil bath at 85 °C. The reaction mixture was stirred vigorously for 2.5 h. After the starting material was completely consumed (monitored by TLC), the reaction mixture was cooled to room temperature, filtered through a silica gel column (230-400 mesh) with chloroform, and the solvent was removed under reduced pressure to obtain the desired compound as a yellow solid product, 4-(2-2-2-trifluoroethoxy)acetophenone monomer. Figure 2 19 The F spectrum showed only one peak at -75.6 ppm, proving that the 4-(2-2-2-trifluoroethoxy)acetophenone monomer was successfully synthesized.

[0046] (2) Preparation of polyaryl-fluoropolymers:

[0047] The 0.15 mmol 4-(2-2-2-trifluoroethoxy)acetophenone monomer obtained in step (1) was dissolved in 2.5 ml of dichloromethane with 1 g of p-terphenyl and 0.85 mmol of N-methylpiperidone. 0.3 ml of trifluoroacetic acid and 2.5 ml of trifluoromethanesulfonic acid were added under ice bath conditions. The mixture was mechanically stirred (at 1000 r) for 72 h. After the reaction was completed, the product was precipitated in saturated potassium carbonate and washed with deionized water until pH=7 to obtain polyaryl-polyfluoropolymer.

[0048] (3) Preparation of quaternized polyaryl-polyfluorinated copolymers:

[0049] 1 g of polyaryl-polyfluorinated copolymer was dissolved in dimethyl sulfoxide, and 1 ml of iodomethane was added. The reaction temperature was controlled at 60 °C, and the reaction time was 24 h. After the reaction was completed, the solution was poured into diethyl ether to precipitate, and washed three times with diethyl ether to remove excess reagent. Quaternized polyaryl-polyfluorinated polyelectrolyte was obtained by vacuum drying at 80 °C. The 1H NMR spectrum of the quaternized polyaryl-polyfluorinated polyelectrolyte is shown below. Figure 3 As shown.

[0050] (4) Preparation of anion exchange membranes:

[0051] 0.5 g of quaternized polyaryl-polyfluorinated polyelectrolyte was dissolved in 10 ml of dimethyl sulfoxide (5 wt%), then poured onto a clean glass plate and dried in an oven at 80 °C for 48 h to prepare the target anion exchange membrane PAP-TP-85-3F. Figure 4 The SEM image shows that the film is very dense and has no surface defects.

[0052] Example 2

[0053] A method for preparing a polyfluorinated side-chain anion exchange membrane includes the following steps:

[0054] (1) Preparation of 4-(2,2,3,3,3-pentafluoropropoxy)acetophenone monomer:

[0055] A double-necked round-bottom flask, dried in an oven, was equipped with a magnetic rotor, a condenser with a top argon balloon at one neck, and a rubber stopper at the other. Cs₂CO₃ (3.02 mmol) (dried under vacuum), Pd₂(dba)₃ (1 mol%) catalyst, and BrettPhos (13.4 mg) ligand were added sequentially to the flask. The flask was then evacuated and repeatedly purged with argon three times. Following this, 1.0 mL of anhydrous toluene was added via syringe, and the mixture was stirred at room temperature for 5 minutes. A solution of 4-fluoroacetophenone (1 mmol) and pentafluoropropanol (110 μL) was added to 1.0 mL of toluene via syringe to the flask. Another 1.0 mL of toluene was added to the reaction flask (for rinsing), and the flask was placed in a preheated oil bath at 85 °C. The reaction mixture was stirred vigorously for 2.5 h. After the raw materials were completely consumed (monitored by TLC), the reaction mixture was cooled to room temperature, filtered through a silica gel column (230-400 mesh) with chloroform, and the solvent was removed under reduced pressure to obtain the desired compound as a yellow liquid product, 4-(2,2,3,3,3-pentafluoropropoxy)acetophenone monomer.

[0056] (2) Preparation of polyaryl-polyfluorinated copolymers:

[0057] The 0.15 mmol 4-(2,2,3,3,3-pentafluoropropoxy)acetophenone monomer obtained in step (1) was dissolved in 2.5 ml of dichloromethane with 1 g of p-terphenyl and 0.85 mmol of N-methylpiperidone. 0.3 ml of trifluoroacetic acid and 2.5 ml of trifluoromethanesulfonic acid were added in an ice bath and the mixture was mechanically stirred (1000 r) for 72 h. After the reaction was completed, the product was precipitated in saturated potassium carbonate and washed with deionized water until pH=7 to obtain polyaryl-polyfluoropolymer.

[0058] (3) Preparation of quaternized polyaryl-polyfluoropolymers:

[0059] 1 g of polyaryl-polyfluorinated copolymer was dissolved in dimethyl sulfoxide, and 1 ml of iodomethane was added. The reaction temperature was controlled at 60 °C, and the reaction time was 24 h. After the reaction was completed, the solution was poured into diethyl ether to precipitate, and washed three times with diethyl ether to remove excess reagent. The quaternized polyaryl-polyfluorinated copolymer was obtained by vacuum drying at 80 °C.

[0060] (4) Preparation of anion exchange membranes:

[0061] 0.5 g of quaternized polyaryl-polyfluorinated copolymer was dissolved in 10 ml of dimethyl sulfoxide (5 wt%), and then poured onto a clean glass plate. The solution was then dried in an oven at 80 °C for 48 h to prepare the target anion exchange membrane PAP-TP-85-5F.

[0062] Example 3

[0063] A method for preparing a polyfluorinated side-chain anion exchange membrane includes the following steps:

[0064] (1) Preparation of 4-(2,2,3,3,4,4,4-heptafluorobutoxy)acetophenone monomer:

[0065] A double-necked round-bottom flask, dried in an oven, was equipped with a magnetic rotor, a condenser with a top argon balloon at one neck, and a rubber stopper at the other. Cs₂CO₃ (3.02 mmol) (dried under vacuum), Pd₂(dba)₃ (1 mol%) catalyst, and BrettPhos (13.4 mg) ligand were added sequentially to the flask. The flask was then evacuated and repeatedly purged with argon three times. Following this, 1.0 mL of anhydrous toluene was added via syringe, and the mixture was stirred at room temperature for 5 minutes. A solution of 4-fluoroacetophenone (1 mmol) and heptafluorobutanol (110 μL) was added to 1.0 mL of toluene via syringe to the flask. Another 1.0 mL of toluene was added to the reaction flask (for rinsing), and the flask was placed in a preheated oil bath at 85 °C. The reaction mixture was stirred vigorously for 2.5 h. After the raw materials were completely consumed (monitored by TLC), the reaction mixture was cooled to room temperature, filtered through a silica gel column (230-400 mesh) with chloroform, and the solvent was removed under reduced pressure to obtain the desired compound as a yellow liquid product, 4-(2,2,3,3,4,4,4-heptafluorobutoxy)acetophenone monomer.

[0066] (2) Preparation of polyaryl-fluoropolymers:

[0067] The 0.15 mmol 4-(2,2,3,3,4,4,4-heptafluorobutoxy)acetophenone monomer obtained in step (1) was dissolved in 2.5 ml of dichloromethane with 1 g of p-terphenyl and 0.85 mmol of N-methylpiperidone. 0.3 ml of trifluoroacetic acid and 2.5 ml of trifluoromethanesulfonic acid were added in an ice bath. The mixture was mechanically stirred (at 1000 r) for 72 h. After the reaction was completed, the product was precipitated in saturated potassium carbonate and washed with deionized water until pH=7 to obtain polyaryl-polyfluorinated copolymer.

[0068] (3) Preparation of quaternized polyaryl-polyfluorinated copolymers:

[0069] 1 g of polyaryl-polyfluorinated copolymer was dissolved in dimethyl sulfoxide, and 1 ml of iodomethane was added. The reaction temperature was controlled at 60 °C, and the reaction time was 24 h. After the reaction was completed, the solution was poured into diethyl ether to precipitate, and washed three times with diethyl ether to remove excess reagent. The quaternized polyaryl-polyfluorinated copolymer was obtained by vacuum drying at 80 °C.

[0070] (4) Preparation of anion exchange membranes:

[0071] 0.5 g of quaternized polyaryl-polyfluorinated copolymer was dissolved in 10 ml of dimethyl sulfoxide (5 wt%), and then poured onto a clean glass plate. The solution was then dried in an oven at 80 °C for 48 h to prepare the target anion exchange membrane PAP-TP-85-7F.

[0072] Table 1. Performance comparison of fluorinated anion exchange membranes in Examples 1-3

[0073]

[0074] As can be seen from the table, the prepared fluorine-containing anion exchange membrane exhibits reduced water absorption rate with increasing fluorine content, thereby reducing ammonia permeation. In addition, fluorine promotes membrane microphase separation, ensuring good conductivity while reducing water absorption rate.

Claims

1. A polyfluorinated side-chain anion exchange membrane, characterized in that, The anion exchange membrane is a polyarylpiperidine polyfluoropolymer, and its general structural formula is shown below: Wherein, Ar is any one of the following monomers, or is copolymerized using any two of the following monomers: Where R is -CF3 or -CH3, 0≤x≤3, 1≤m≤30.

2. The method for preparing a polyfluorinated side-chain anion exchange membrane according to claim 1, characterized in that, Includes the following steps: (1) Preparation of polyfluoroacetophenone monomer: In the presence of Cs2CO3, Pd2(dba)3 catalyst and BrettPhos ligand, aryl halides and alcohols react at 80-90℃ for 2-5 h to obtain polyfluoroacetophenone monomers. (2) Preparation of polyaryl-fluoropolymers: The polyfluoroacetophenone monomer obtained in step (1) was dissolved in dichloromethane along with aryl monomer and 1-methyl-4-piperidinone. Trifluoroacetic acid and trifluoromethanesulfonic acid were added under ice bath conditions, and the mixture was stirred for 48-72 h. After the reaction was completed, the product was precipitated in alkaline solution and washed with deionized water to obtain polyaryl-polyfluoropolymer. (3) Preparation of quaternized polyaryl-polyfluorinated copolymers: Dissolve the polyaryl-polyfluorinated copolymer in a good solvent with a mass concentration of 5-10 wt%, add iodomethane, control the reaction temperature at 30-60℃, and the reaction time at 24-48 h; after the reaction is completed, drop the reaction solution into diethyl ether or ethyl acetate to precipitate the product, wash with ethyl acetate or diethyl ether, and dry to obtain the quaternized polyaryl-polyfluorinated copolymer. (4) Preparation of anion exchange membranes: The quaternized polyaryl-polyfluorinated copolymer was dissolved in a good solvent to obtain a quaternized polyaryl-polyfluorinated copolymer solution with a mass fraction of 2.5-10 wt%. Subsequently, the target anion exchange membrane was prepared by casting at 80-120 °C.

3. The method for preparing a polyfluorinated side-chain anion exchange membrane as described in claim 2, characterized in that, The aryl halide is one or more of 4-bromoacetophenone, 4-fluoroacetophenone, 4-chloroacetophenone, 2,2,2,4'-tetrafluoroacetophenone, 4'-bromo-2,2,2-trifluoroacetophenone, and 4'-chloro-2,2,2-trifluoroacetophenone, and the alcohol is one or more of trifluoroethanol, pentafluoropropanol, heptafluorobutanol, and 1H,1H-nonafluoro-1-pentanol.

4. The method for preparing a polyfluorinated side-chain anion exchange membrane as described in claim 2, characterized in that, The molar ratio of the aryl halide to the alcohol is 1:1.1-5, and the molar ratio of the Cs2CO3, Pd2(dba)3 catalyst and BrettPhos ligand to the aryl halide is 1.2-2:0.4-0.6:0.01-0.03:

1.

5. The method for preparing a polyfluorinated side-chain anion exchange membrane as described in claim 2, characterized in that, The molar ratio of the aryl monomer, polyfluoroacetophenone monomer and 1-methyl-4-piperidinone is 10:5 to 1:5 to 9, and the molar ratio of the aryl monomer, trifluoroacetic acid and trifluoromethanesulfonic acid is 1:1 to 1.5:5 to 10.

6. The method for preparing a polyfluorinated side-chain anion exchange membrane as described in claim 2, characterized in that, The molar ratio of the polyaryl-polyfluorinated copolymer to iodomethane is 1:1-10.

7. The method for preparing a polyfluorinated side-chain anion exchange membrane as described in claim 2, characterized in that, In step (1), the reaction solvent is one of toluene, methyl chloride, or methanol, and the ratio of aryl halide to reaction solvent is 1-2 mmol: 1 ml; in steps (3) and (4), the good solvent is dimethyl sulfoxide, N,N-dimethylformamide, N-methylpyrrolidone, or N,N-dimethylacetamide.

8. The method for preparing a polyfluorinated side-chain anion exchange membrane as described in claim 2, characterized in that, In step (2), the ratio of the aryl monomer to the good solvent is 1 mmol: 0.9-1.5 mL, the alkaline solution is either a saturated potassium carbonate solution or a 1-5 mol / L KOH solution; in step (3), the mass concentration of the polyaryl-polyfluorinated copolymer in the good solvent is 5-10 wt%.

9. The method for preparing a polyfluorinated side-chain anion exchange membrane as described in claim 2, characterized in that, In step (4), the casting method specifically involves pouring the quaternized polyaryl-polyfluorinated polyelectrolyte solution onto a clean glass plate and drying it in an oven at 80-120℃ for 24-48 hours to obtain the target anion exchange membrane.

10. The application of the polyfluorinated side-chain anion exchange membrane according to claim 1 in ammonia fuel cells or electrolytic ammonia water.

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