Organic hybrid ionic solvent membrane as well as preparation method and application thereof

Abstract

The invention belongs to the field of material chemistry, and particularly relates to an organic hybrid ionic solvent membrane as well as a preparation method and application thereof. The organic hybrid ionic solvent membrane provided by the invention is prepared from a membrane liquid, wherein the membrane liquid comprises an organic porous material, a biphenyl-isatin polymer and a solvent; the organic porous material is formed by condensation polymerization of a tri-functionality aldehyde monomer and a bi-functionality amine monomer through a Schiff base reaction. A specific organic porous material is introduced into the biphenyl-isatin polymer ionic solvent membrane, so that the affinity of the ionic solvent membrane and water is remarkably improved, the alkali absorption efficiency of the membrane in an alkaline solution is improved, the surface resistance of the membrane is reduced, and the performance of the membrane is improved. Therefore, the alkaline electrolytic cell assembled on the basis of the ionic solvent membrane shows excellent electrochemical performance. Experimental results show that the water contact angle of the organic hybrid ionic solvent membrane is smaller than 50 degrees, the alkali absorption rate is larger than 20%, and the surface resistance is smaller than 0.2 omega cm < 2 >.

Description

Technical Field

[0001] The invention belongs to the field of material chemistry, and in particular relates to an organic hybrid ion solvent membrane and a preparation method and application thereof. Background Art

[0002] As a clean energy, hydrogen can partially replace carbon-based fossil energy and help reduce carbon dioxide emissions, and its importance is becoming increasingly evident. Therefore, the development of the hydrogen energy industry has become one of the important means to achieve the goals of carbon peak and carbon neutrality, and it has great strategic significance.

[0003] The alkaline electrolyzer based on ion solvent membrane (ISM) is based on green hydrogen (H 2 ) energy. The ion solvent membrane is the core component of the electrolyzer, playing a key role in isolating hydrogen and oxygen and conducting hydroxide ions, which directly affects the basic properties of the electrolyzer, such as current density and energy consumption. The ideal ion solvent membrane needs to have excellent chemical stability, high alkali absorption rate, low surface resistance, etc. Among them, the alkali absorption rate is one of the key prerequisites affecting the electrolysis efficiency. With a high alkali absorption rate, the alkali conduction resistance in the membrane is reduced, and the overall surface resistance of the membrane is reduced, thereby improving the overall electrolysis efficiency. ISM based on biphenyl-insigmatine polymer is one of the common choices at present. However, this type of polymer membrane material has poor hydrophilicity (water contact angle>70o), low alkali absorption rate (<13%), and high surface resistance (>0.3Ωcm 2 ) and other issues have greatly limited its application in the field of alkaline electrolyzed water. Summary of the invention

[0004] In view of this, the object of the present invention is to provide an organic hybrid ion solvent membrane and a preparation method and application thereof. The organic hybrid ion solvent membrane provided by the present invention has good hydrophilicity, high alkali absorption efficiency and low surface resistance.

[0005] The present invention provides an organic hybrid ion solvent membrane, which is made of a membrane liquid, wherein the components of the membrane liquid include an organic porous material, a biphenyl-isatin polymer and a solvent;

[0006] The organic porous material is formed by polycondensation of trifunctional aldehyde monomers and difunctional amine monomers through Schiff base reaction.

[0007] Preferably, the trifunctional aldehyde monomer is one or more of trimesaldehyde, trialdehyde phloroglucinol, tris(4-formylphenyl)amine, 2,4,6-tris(4-formylphenyl)-1,3,5-triazine, 1,3,5-tris(p-formylphenyl)benzene, 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine, [1,3,5-trimethyl-2,4,6-tris(4'-formylphenyl)]benzene, 1,3,5-trimethoxy-2,4,6-triformylbenzene and tris(tetrabenzaldehyde)phosphine.

[0008] Preferably, the difunctional amine monomer is one or more of 3,3'-dimethoxybenzidine, 1-hydrogen-indazole-4,7-diamine, 3,3'-diaminodiphenyl sulfone, 2,5-bis(2-methoxyethoxy)terephthalohydrazide, 2,5-bis(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)terephthalohydrazide, 2,5-dimethoxyterephthalohydrazide, 2,4-diamino-1,3,5-triazine, [3,3'-di-1,2,4-1H-triazole]-5,5'-diamine and ethidium bromide.

[0009] Preferably, the biphenyl-isatin polymer is copolymerized by biphenyl and isatis, and the mass ratio of biphenyl to isatis is (15-30):15.

[0010] Preferably, the mass ratio of the organic porous material to the biphenyl-isatin polymer is (0.01-0.1):8.

[0011] The present invention provides a method for preparing the organic hybrid ion solvent membrane described in the above technical solution, comprising the following steps:

[0012] The membrane liquid is cast onto a flat plate and dried to obtain an organic hybrid ion solvent membrane; the components of the membrane liquid include organic porous material, biphenyl-isatin polymer and solvent.

[0013] Preferably, the organic porous material is prepared according to the following steps:

[0014] Under acid catalysis conditions, trifunctional aldehyde monomers and difunctional amine monomers undergo Schiff base reaction in an organic solvent to obtain an organic porous material.

[0015] Preferably, the temperature of the Schiff base reaction is 80 to 150° C.; and the time of the Schiff base reaction is 3 to 12 days.

[0016] Preferably, the biphenyl-isatin polymer is prepared according to the following steps:

[0017] Under acid catalysis conditions, biphenyl and isatin undergo copolymerization in an organic solvent to obtain a biphenyl-isatin polymer.

[0018] The present invention provides an alkaline electrolytic cell, comprising the organic hybrid ion solvent membrane described in the above technical solution.

[0019] Compared with the prior art, the present invention provides an organic hybrid ion solvent membrane and a preparation method and application thereof. The organic hybrid ion solvent membrane provided by the present invention is made of a membrane liquid, the components of which include an organic porous material, a biphenyl-isatin polymer and a solvent; the organic porous material is formed by condensation polymerization of a trifunctional aldehyde monomer and a difunctional amine monomer through a Schiff base reaction. The present invention introduces a specific organic porous material into the biphenyl-isatin polymer ion solvent membrane material, which significantly improves the affinity between the ion solvent membrane and water, improves the alkali absorption efficiency of the membrane in alkaline solution, and reduces the surface resistance of the membrane, so that the alkaline electrolytic cell assembled based on the ion solvent membrane exhibits excellent electrochemical performance. Experimental results show that the water contact angle of the organic hybrid ion solvent membrane provided by the present invention is less than 50°, the alkali absorption rate is greater than 20%, and the surface resistance is less than 0.2Ωcm 2 . BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0021] Figure 1 is a schematic structural diagram of an organic porous material provided by an embodiment of the present invention;

[0022] Figure 2 It is a polarization curve diagram provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] The invention provides an organic hybrid ion solvent membrane, which is made by film liquid casting and drying. The components of the film liquid include organic porous material, biphenyl-isatin polymer and solvent.

[0025] In the organic hybrid ion solvent membrane provided by the present invention, in the membrane solution, the organic porous material is formed by polycondensation of trifunctional aldehyde monomers and difunctional amine monomers through Schiff base reaction, and its structure is as follows: Figure 1 As shown, Figure 1 In the above formula, X is derived from a trifunctional aldehyde monomer, and Y is derived from a difunctional amine monomer.

[0026] In the organic hybrid ion solvent membrane provided by the present invention, among the raw materials used to synthesize the organic porous material, the trifunctional aldehyde monomer includes but is not limited to one or more of trimesicaldehyde, trialdehyde phloroglucinol, tris(4-formylphenyl)amine, 2,4,6-tris(4-formylphenyl)-1,3,5-triazine, 1,3,5-tris(p-formylphenyl)benzene, 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine, [1,3,5-trimethyl-2,4,6-tris(4'-formylphenyl)]benzene, 1,3,5-trimethoxy-2,4,6-triformylbenzene and tris(tetrabenzaldehyde)phosphine.

[0027] In the organic hybrid ion solvent membrane provided by the present invention, among the raw materials used to synthesize the organic porous material, the difunctional amine monomers include but are not limited to one or more of 3,3'-dimethoxybenzidine, 1-hydrogen-indazole-4,7-diamine, 3,3'-diaminodiphenyl sulfone, 2,5-dimethoxyterephthalohydrazide, 2,4-diamino-1,3,5-triazine, 2,5-bis(2-methoxyethoxy)terephthalohydrazide, [3,3'-di-1,2,4-1H-triazole]-5,5'-diamine, 2,5-bis(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)terephthalohydrazide and ethidium bromide.

[0028] In the organic hybrid ion solvent membrane provided by the present invention, in the raw materials used to synthesize the organic porous material, the molar ratio of the trifunctional aldehyde monomer to the difunctional amine monomer is preferably 2:3.

[0029] In the organic hybrid ion solvent membrane provided by the present invention, in the membrane liquid, the biphenyl-isatin polymer is copolymerized by biphenyl and isatin, and the mass ratio of the biphenyl to isatin is preferably (15-30):15, specifically 15:15, 16:15, 17:15, 18:15, 19:15, 20:15, 21:15, 22:15, 23:15, 24:15, 25:15, 26:15, 27:15, 28:15, 29:15 or 30:15.

[0030] In the organic hybrid ion solvent membrane provided by the present invention, in the membrane liquid, the mass ratio of the organic porous material to the biphenyl-isatin polymer is preferably (0.01-0.1):8, specifically 0.01:8, 0.015:8, 0.02:8, 0.025:8, 0.03:8, 0.035:8, 0.04:8, 0.045:8, 0.05:8, 0.055:8, 0.06:8, 0.065:8, 0.07:8, 0.075:8, 0.08:8, 0.085:8, 0.09:8, 0.095:8 or 0.1:8.

[0031] In the organic hybrid ion solvent membrane provided by the present invention, in the membrane liquid, the solvent includes but is not limited to one or more of dimethylacetamide (DMAc), dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and N-methylpyrrolidone (NMP); the dosage ratio of the solvent to the biphenyl-isatin polymer is preferably (50-200) mL:8 g, specifically 50 mL:8 g, 60 mL:8 g, 70 mL:8 g, 80 mL:8 g, 90 mL:8 g, 100 mL:8 g, 110 mL:8 g, 120 mL:8 g, 130 mL:8 g, 140 mL:8 g, 150 mL:8 g, 160 mL:8 g, 170 mL:8 g, 180 mL:8 g, 190 mL:8 g or 200 mL:8 g.

[0032] In the organic hybrid ion solvent membrane provided by the present invention, the thickness of the organic hybrid ion solvent membrane is preferably 60-90 μm, specifically 60 μm, 61 μm, 62 μm, 63 μm, 64 μm, 65 μm, 66 μm, 67 μm, 68 μm, 69 μm, 70 μm, 71 μm, 72 μm, 73 μm, 74 μm, 75 μm, 76 μm, 77 μm, 78 μm, 79 μm, 80 μm, 81 μm, 82 μm, 83 μm, 84 μm, 85 μm, 86 μm, 87 μm, 88 μm, 89 μm or 90 μm.

[0033] The present invention also provides a method for preparing the organic hybrid ion solvent membrane described in the above technical solution, comprising the following steps:

[0034] The membrane liquid is cast onto a flat plate and dried to obtain an organic hybrid ion solvent membrane; the components of the membrane liquid include organic porous material, biphenyl-isatin polymer and solvent.

[0035] In the preparation method provided by the present invention, in the membrane solution, the organic porous material is preferably prepared according to the following steps:

[0036] Under acid catalysis conditions, trifunctional aldehyde monomers and difunctional amine monomers undergo Schiff base reaction in an organic solvent to obtain an organic porous material.

[0037] In the above-mentioned steps for preparing the organic porous material provided by the present invention, the type selection and dosage ratio of the trifunctional aldehyde monomer and the difunctional amine monomer have been introduced in the previous text and will not be repeated here.

[0038] In the above-mentioned organic porous material preparation steps provided by the present invention, the acid catalysis condition is provided by an acid solution, preferably by acetic acid; the concentration of the acetic acid is preferably 3 mol / L, 6 mol / L or pure acetic acid; the dosage ratio of the acetic acid to the trifunctional aldehyde monomer is preferably (0.5-3) mL:1.6 mmol, specifically 0.5 mL:1.6 mmol, 0.6 mL:1.6 mmol, 0.7 mL:1.6 mmol, 0.8 mL:1.6 mmol, 0.9 mL:1.6 mmol, 1 mL:1.6 mmol, 1.2 mL:1.6 mmol, 1.5 mL:1.6 mmol, 1.7 mL:1.6 mmol, 2 mL:1.6 mmol, 2.3 mL:1.6 mmol, 2.5 mL:1.6 mmol, 2.7 mL:1.6 mmol or 3 mL:1.6 mmol.

[0039] In the above-mentioned organic porous material preparation steps provided by the present invention, the organic solvent includes but is not limited to one or more of dioxane, DMAc, m-trimethylbenzene, o-dichlorobenzene, toluene and n-butanol; the dosage ratio of the organic solvent to the trifunctional aldehyde monomer is preferably (5-20) mL:1.6 mmol, specifically 5 mL:1.6 mmol, 6 mL:1.6 mmol, 7 mL:1.6 mmol, 8 mL:1.6 mmol, 9 mL:1.6 mmol, 10 mL:1.6 mmol, 11 mL:1.6 mmol, 12 mL:1.6 mmol, 13 mL:1.6 mmol, 14 mL:1.6 mmol, 15 mL:1.6 mmol, 16 mL:1.6 mmol, 17 mL:1.6 mmol, 18 mL:1.6 mmol, 19 mL:1.6 mmol or 20 mL:1.6 mmol.

[0040] In the above-mentioned organic porous material preparation steps provided by the present invention, the temperature of the Schiff base reaction is preferably 80-150°C, specifically 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C or 150°C; the time of the Schiff base reaction is preferably 3-12 days, specifically 3 days, 4 days, 5 days, 6 days, 7 days, 8 days, 9 days, 10 days, 11 days or 12 days.

[0041] In the above-mentioned steps for preparing the organic porous material provided by the present invention, a more specific preparation process preferably includes: dispersing a trifunctional aldehyde monomer and a difunctional amine monomer in an organic solvent, dropping an acid solution, and heating the reaction; wherein, before the heating reaction, the mixed system is preferably first frozen with liquid nitrogen, then replaced with nitrogen, and then sealed and thawed; after the heating reaction is completed, the obtained reaction product is preferably washed and dried.

[0042] In the preparation method provided by the present invention, in the membrane solution, the biphenyl-isatin polymer is preferably prepared according to the following steps:

[0043] Under acid catalysis conditions, biphenyl and isatin undergo copolymerization in an organic solvent to obtain a biphenyl-isatin polymer.

[0044] In the above-mentioned biphenyl-isatin polymer preparation step provided by the present invention, the dosage ratio of the biphenyl and isatis has been introduced in the previous text and will not be repeated here.

[0045] In the above-mentioned biphenyl-isatin polymer preparation step provided by the present invention, the acid catalysis condition is provided by an acid solution, preferably by a mixed acid of trifluoromethanesulfonic acid and trifluoroacetic acid; the volume ratio of trifluoromethanesulfonic acid to trifluoroacetic acid in the mixed acid is preferably (2-6):1, more preferably 4:1; the amount ratio of the mixed acid to biphenyl is preferably (80-150) mL:15 g, specifically 80 mL:15 g, 85 mL:15 g, 90 mL:15 g, 95 mL:15 g, 100 mL:15 g, 105 mL:15 g, 110 mL:15 g, 115 mL:15 g, 120 mL:15 g, 125 mL:15 g, 130 mL:15 g, 135 mL:15 g, 140 mL:15 g, 145 mL:15 g or 150 mL:15 g.

[0046] In the above-mentioned biphenyl-isatin polymer preparation step provided by the present invention, the organic solvent includes but is not limited to dichloromethane; the usage ratio of the organic solvent to biphenyl is preferably (80-150) mL:15 g, specifically 80 mL:15 g, 85 mL:15 g, 90 mL:15 g, 95 mL:15 g, 100 mL:15 g, 105 mL:15 g, 110 mL:15 g, 115 mL:15 g, 120 mL:15 g, 125 mL:15 g, 130 mL:15 g, 135 mL:15 g, 140 mL:15 g, 145 mL:15 g or 150 mL:15 g.

[0047] In the above-mentioned biphenyl-isatin polymer preparation steps provided by the present invention, the temperature of the copolymerization reaction is preferably -5 to 5°C, specifically -5°C, -4°C, -3°C, -2°C, -1°C, 0°C, 1°C, 2°C, 3°C, 4°C or 5°C; the time of the copolymerization reaction is preferably 6 to 24h, specifically 6h, 8h, 10h, 12h, 14h, 16h, 18h, 20h, 22h or 24h.

[0048] In the above-mentioned biphenyl-isatin polymer preparation steps provided by the present invention, a more specific preparation process preferably includes: dispersing biphenyl and isatin in an organic solvent, adding acid solution for reaction; wherein, after the reaction is completed, the obtained reaction product is preferably precipitated with water, washed and dried.

[0049] In the preparation method provided by the present invention, the specific type of the solvent in the membrane solution, as well as the dosage ratio of the organic porous material, the biphenyl-isatin polymer and the solvent have been introduced in the previous text and will not be repeated here.

[0050] In the preparation method provided by the present invention, the membrane solution is preferably prepared according to the following steps:

[0051] The organic porous material and the biphenyl-isatin polymer are dispersed in a solvent, centrifuged, and defoamed to obtain a membrane liquid.

[0052] In the preparation method provided by the present invention, the drying method is preferably drying and / or vacuum drying; more preferably, drying is performed first and then vacuum drying is performed. Wherein, the drying temperature is preferably 40 to 80°C, specifically 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C or 80°C; the drying time is preferably 2 to 12h, more preferably 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h or 12h; the vacuum drying temperature is preferably 60 to 100°C, specifically 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C or 100°C; the vacuum drying time is preferably 2 to 12h, more preferably 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h or 12h.

[0053] The present invention also provides an alkaline electrolytic cell, comprising the organic hybrid ion solvent membrane described in the above technical solution.

[0054] The technical solution provided by the present invention introduces a specific organic porous material into the biphenyl-isatin polymer ion solvent membrane material, which significantly improves the affinity between the ion solvent membrane and water, improves the alkali absorption efficiency of the membrane in alkaline solution, and reduces the surface resistance of the membrane, so that the alkaline electrolytic cell assembled based on the ion solvent membrane exhibits excellent electrochemical performance. Experimental results show that the water contact angle of the organic hybrid ion solvent membrane provided by the present invention is less than 50°, the alkali absorption rate is greater than 20%, and the surface resistance is less than 0.2Ωcm 2 .

[0055] For the purpose of greater clarity, the present invention is described in detail with reference to the following examples and comparative examples.

[0056] Example 1

[0057] (1) Preparation of organic porous materials:

[0058] Take 2.4mmol ethidium bromide and 1.6mmol 1,3,5-trimethoxy-2,4,6-triformylbenzene and disperse them in 5mL dioxane / m-trimethylbenzene (v / v, 1 / 1), add 0.5mL 6M acetic acid dropwise, freeze with liquid nitrogen and replace nitrogen three times, then seal and thaw, react at 120℃ for 3 days to obtain a crude product, wash with dichloromethane, tetrahydrofuran and acetone, and dry in vacuum to obtain a solid product.

[0059] (2) Preparation of biphenyl-indigo polymer:

[0060] Disperse 16 g of indigo carmine and 15 g of biphenyl in 120 mL of dichloromethane at 0°C, add 120 mL of mixed acid (trifluoromethanesulfonic acid: trifluoroacetic acid = 4:1, volume ratio) dropwise, react for 12 hours after the acid addition is completed, pour the reaction solution into deionized water to obtain a filamentous polymer, add 5% sodium bicarbonate solution to wash, and then repeatedly wash with deionized water until neutral, filter the solid polymer and dry it to obtain the final product.

[0061] (3) Preparation of organic hybrid ion solvent membrane:

[0062] Take 30 mg of the above-mentioned organic porous material and 8 g of the above-mentioned biphenyl-isatin polymer and disperse them in 100 mL of DMAc. After ultrasonication for 30 minutes, centrifuge, take the upper layer of dispersion liquid for degassing and cast it onto a glass plate; after drying at 60°C for 6 hours, vacuum dry at 80°C for 6 hours, remove the membrane, and obtain an organic hybrid ion solvent membrane with a thickness of about 67 μm.

[0063] Example 2

[0064] (1) Preparation of organic porous materials:

[0065] Take 2.4mmol ethidium bromide and 1.6mmol tri(4-formylphenyl)amine and disperse them in 8mL DMAc / o-dichlorobenzene (v / v, 2 / 0.5), add 0.5mL pure acetic acid dropwise, freeze with liquid nitrogen and replace nitrogen three times, then seal and thaw, react at 100℃ for 5 days to obtain a crude product, then wash with dichloromethane, DMAc and acetone, and dry in vacuum to obtain a solid product.

[0066] (2) Preparation of organic hybrid ion solvent membrane:

[0067] Take 30 mg of the above-mentioned organic porous material and 8 g of the biphenyl-isatin polymer prepared in Example 1 and disperse them in 100 mL of DMAc. After ultrasonication for 30 minutes, centrifuge, take the upper layer of dispersion liquid for degassing and cast it onto a glass plate; after drying at 60°C for 6 hours, vacuum dry at 80°C for 6 hours, remove the membrane, and obtain an organic hybrid ion solvent membrane with a thickness of about 66 μm.

[0068] Example 3

[0069] (1) Preparation of organic porous materials:

[0070] 2.4 mmol 3,3'-dimethoxybenzidine and 1.6 mmol trialdehyde phloroglucinol were dispersed in 5 mL dioxane / trimethylbenzene (v / v, 1 / 1.5), 0.5 mL 3 M acetic acid was added dropwise, and the mixture was frozen with liquid nitrogen and replaced with nitrogen three times. The mixture was then sealed and thawed, and reacted at 120 °C for 3 days to obtain a crude product. The crude product was then washed with dichloromethane, tetrahydrofuran and acetone, and then dried in vacuum to obtain a solid product.

[0071] (2) Preparation of organic hybrid ion solvent membrane:

[0072] Take 30 mg of the above-mentioned organic porous material and 8 g of the biphenyl-isatin polymer prepared in Example 1 and disperse them in 100 mL of DMAc. After ultrasonication for 30 minutes, centrifuge, take the upper layer of dispersion liquid for degassing and cast it onto a glass plate; after drying at 60°C for 6 hours, vacuum dry at 80°C for 6 hours, remove the membrane, and obtain an organic hybrid ion solvent membrane with a thickness of about 68 μm.

[0073] Example 4

[0074] (1) Preparation of organic porous materials:

[0075] Take 2.4mmol 2,4-diamino-1,3,5-triazine and 1.6mmol 1,3,5-tri(p-formylphenyl)benzene and disperse them in 8mL dioxane / o-dichlorobenzene (v / v, 3 / 1), add 1mL pure acetic acid dropwise, freeze with liquid nitrogen and replace nitrogen three times, then seal and thaw, react at 110℃ for 6 days to obtain a crude product, then wash with tetrahydrofuran, DMAc and acetone, and vacuum dry to obtain a solid product.

[0076] (2) Preparation of organic hybrid ion solvent membrane:

[0077] Take 30 mg of the above-mentioned organic porous material and 8 g of the biphenyl-isatin polymer prepared in Example 1 and disperse them in 100 mL of DMAc. After ultrasonication for 30 minutes, centrifuge, take the upper layer of dispersion liquid for degassing and cast it onto a glass plate; after drying at 60°C for 6 hours, vacuum dry at 80°C for 6 hours, remove the membrane, and obtain an organic hybrid ion solvent membrane with a thickness of about 68 μm.

[0078] Example 5

[0079] (1) Preparation of organic porous materials:

[0080] Take 2.4mmol ethidium bromide and 1.6mmol [1,3,5-trimethyl-2,4,6-tris (4'-formylphenyl)] benzene and disperse them in 5mL dioxane / DMAc (v / v, 5 / 1), add 0.8mL 6M acetic acid dropwise, freeze with liquid nitrogen and replace nitrogen three times, then seal and thaw, react at 120℃ for 5 days to obtain a crude product, then wash with dichloromethane, DMAc and acetone, and dry in vacuum to obtain a solid product.

[0081] (2) Preparation of organic hybrid ion solvent membrane:

[0082] Take 30 mg of the above-mentioned organic porous material and 8 g of the biphenyl-isatin polymer prepared in Example 1 and disperse them in 100 mL of DMAc. After ultrasonication for 30 minutes, centrifuge, take the upper layer of dispersion liquid for degassing and cast it onto a glass plate; after drying at 60°C for 6 hours, vacuum dry at 80°C for 6 hours, remove the membrane, and obtain an organic hybrid ion solvent membrane with a thickness of about 70 μm.

[0083] Comparative Example 1

[0084] Take g of the biphenyl-isatin polymer prepared in Example 1 and disperse it in 100 mL of DMAc. After ultrasonication for 30 min, centrifuge. Take the upper layer of the dispersion and degas it, then cast it onto a glass plate. After drying at 60°C for 6 h, vacuum dry at 80°C for 6 h, remove the membrane, and obtain an ionic solvent membrane with a thickness of about 67 μm.

[0085] Performance Evaluation

[0086] (1) Contact angle test: The contact angle was tested using German Dataphysics OCA20.

[0087] (2) Alkali absorption rate test: The membrane was fully soaked in 6M alkali solution and the wet membrane mass M1 was recorded. Then, it was dried and the mass was recorded M2. Finally, it was washed with water until neutral and dried, and the mass was recorded M3. Alkali absorption rate = (M2-M3) / M1.

[0088] (3) Surface resistance test: The test was conducted using a two-electrode system of an electrochemical workstation in an H-type cell. Before the test, equal volumes of 6 M KOH concentrated alkaline solution were poured into two independent half cells. The surface resistance was calculated using the following formula: R = (r2-r1) × S; where rl is the internal resistance of the cell without membrane loading, r2 is the internal resistance of the cell after membrane assembly, and S is the effective contact area of ​​the membrane.

[0089] (4) Polarization curve test: Pure nickel mesh foam was used as the cathode and anode catalysts. The pure nickel mesh foam was placed in a hot press and hot-pressed at 80 to 120° C. for 0.5 to 10 minutes. Then, the membrane obtained in the embodiment or comparative example was sandwiched between two nickel mesh foam electrodes to obtain a membrane electrode assembly with an effective area of ​​4 cm 2 The membrane electrode assembly was sandwiched between the cathode and the anode to assemble the water electrolysis device, and the electrochemical test was carried out in 6MKOH electrolyte at 80°C.

[0090] The contact angle, alkali absorption rate and surface resistance test results of the ion solvent membrane are shown in Table 1:

[0091] Table 1 Contact angle, alkali absorption rate and surface resistance test results of ionic solvent membrane

[0092] <![CDATA[Contact angle( o )]]> Alkali absorption rate (%) <![CDATA[Sheet Resistance (Ωcm 2 )]]> Comparative Example 73.8 10.9 0.35 Example 1 47.3 22.9 0.18 Example 2 43 25 0.14 Example 3 45.6 24 0.16 Example 4 45 24.3 0.17 Example 5 46.7 23.3 0.18

[0093] It can be seen from Table 1 that, compared with the ionic solvent membrane prepared in the comparative example without introducing the organic porous material, the contact angle of the organic hybrid ionic solvent membrane prepared in the example is significantly reduced, while the alkali absorption rate is improved and the surface resistance is reduced.

[0094] The polarization curve test results of the ionic solvent membrane are as follows: Figure 2 As shown, Figure 2 is a polarization curve diagram provided by an embodiment of the present invention. Figure 2 It can be seen that compared with the ion solvent membrane prepared in the comparative example without introducing the organic porous material, the water electrolysis performance of the organic hybrid ion solvent membrane prepared in the example is significantly improved, and the voltage is significantly reduced at the same current density.

[0095] The above is only 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 principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An organic hybrid ion solvent membrane, made of a membrane solution, wherein the components of the membrane solution include an organic porous material, a biphenyl-isatin polymer and a solvent; The organic porous material is formed by polycondensation of trifunctional aldehyde monomers and difunctional amine monomers through Schiff base reaction.

2. The organic hybrid ion solvent membrane according to claim 1, It is characterized in that The trifunctional aldehyde monomer is one or more of trimesaldehyde, trialdehyde phloroglucinol, tris(4-formylphenyl)amine, 2,4,6-tris(4-formylphenyl)-1,3,5-triazine, 1,3,5-tris(p-formylphenyl)benzene, 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine, [1,3,5-trimethyl-2,4,6-tris(4'-formylphenyl)]benzene, 1,3,5-trimethoxy-2,4,6-triformylbenzene and tris(tetrabenzaldehyde)phosphine.

3. The organic hybrid ion solvent membrane according to claim 1, It is characterized in that The difunctional amine monomer is one or more of 3,3'-dimethoxybenzidine, 1-hydrogen-indazole-4,7-diamine, 3,3'-diaminodiphenyl sulfone, 2,5-dimethoxyterephthalohydrazide, 2,4-diamino-1,3,5-triazine, [3,3'-di-1,2,4-1H-triazole]-5,5'-diamine, ethidium bromide, 2,5-bis(2-methoxyethoxy)terephthalohydrazide and 2,5-bis(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)terephthalohydrazide.

4. The organic hybrid ion solvent membrane according to claim 1, It is characterized in that The biphenyl-isatin polymer is formed by copolymerization of biphenyl and isatis, and the mass ratio of the biphenyl to isatis is (15-30):

15.

5. The organic hybrid ion solvent membrane according to claim 1, wherein the mass ratio of the organic porous material to the biphenyl-isatin polymer is (0.01-0.1):

8.

6. A method for preparing the organic hybrid ion solvent membrane according to any one of claims 1 to 5, The following steps are involved: The membrane liquid is cast onto a flat plate and dried to obtain an organic hybrid ion solvent membrane; the components of the membrane liquid include organic porous material, biphenyl-isatin polymer and solvent.

7. The preparation method according to claim 6, It is characterized in that The organic porous material is prepared according to the following steps: Under acid catalysis conditions, trifunctional aldehyde monomers and difunctional amine monomers undergo Schiff base reaction in an organic solvent to obtain an organic porous material.

8. The preparation method according to claim 7, It is characterized in that The temperature of the Schiff base reaction is 80 to 150° C.; the time of the Schiff base reaction is 3 to 12 days.

9. The preparation method according to claim 6, It is characterized in that The biphenyl-isatin polymer is prepared according to the following steps: Under acid catalysis conditions, biphenyl and isatin undergo copolymerization in an organic solvent to obtain a biphenyl-isatin polymer.

10. An alkaline electrolytic cell comprising the organic hybrid ion solvent membrane according to any one of claims 1 to 5.

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