Dehydration resistance reduction type ion exchange membrane as well as preparation method and application thereof

Abstract

The invention relates to a dehydration resistance reduction type ion exchange membrane and a preparation method and application thereof, and belongs to the technical field of ion exchange membrane materials and new energy. The preparation method comprises the following steps: performing surface modification on a precursor by using a modifier, and forming a film through a film forming process. The precursor is a two-dimensional nanosheet and / or a monomer, and the modifier is a compound capable of stripping a target ion ionized shell layer through a specific binding effect or a space confinement effect and comprises at least one of hydrocarbons, ethers, amino acids and a super-ionic conductor, so that the target ions efficiently migrate in the membrane in a bare ion form; therefore, the ion transmission rate is obviously improved. The obtained dehydration and resistance reduction type ion exchange membrane has excellent power generation performance, and is suitable for salinity gradient power generation scenes, such as river-sea system osmotic energy collection.

Description

Technical Field

[0001] This invention relates to the fields of ion exchange membrane materials and new energy technologies, and in particular to a dehydration drag-reducing ion exchange membrane, its preparation method, and its application. Background Technology

[0002] Driven by the urgent need for global energy structure transformation, salinity gradient energy (SGR), an environmentally friendly renewable energy source with abundant reserves (estimated at approximately 2.6 TW), has become a research hotspot in the renewable energy field due to its natural existence at the seawater-freshwater interface. Reverse electrodialysis (RED) technology, as one of the core pathways for SGR conversion, operates on the principle of separating high- and low-salinity solutions using ion-exchange membranes (IEMs). The salinity gradient drives the directional migration of ions, generating an electric current, thereby converting SGR energy into electrical energy. In this process, the magnitude of ion transport resistance directly determines the energy conversion efficiency and power density of the RED system, and is a key factor restricting its industrial feasibility.

[0003] However, the structural characteristics of traditional ion exchange membranes severely restrict efficient ion transport, and their inherent problems directly exacerbate ion transport resistance. Traditional ion exchange membranes, using dense polymer substrates, have tortuous ion diffusion paths and uneven pore sizes, resulting in significant diffusion resistance for ions migrating within the membrane. Simultaneously, the electrostatic repulsion and adsorption on the polymer membrane surface create significant membrane-solution interfacial resistance, hindering ions from entering the membrane phase from the solution phase. More critically, the pore structure of traditional membranes cannot achieve precise confinement and control of ions, further exacerbating ion transport resistance. The superposition of these multiple resistances keeps the ion migration rate of traditional RED systems consistently low, with power densities far below the 5 W / m² threshold required for industrial applications.

[0004] To overcome this constraint, researchers have conducted extensive research on the structural optimization of ion exchange membranes in recent years. The structure of ion exchange membranes has evolved from one-dimensional nanochannels with low flux, dispersed resistance, and poor scalability to two-dimensional layered structures and three-dimensional network architectures with strong channel continuity, controllable interfacial interactions, and easier resistance regulation. Materials that are readily available and easily regulated, such as graphene oxide (GO), MXenes, and montmorillonite, have become ideal carriers for constructing low-resistance angstrom-level ion channels. Their core advantage lies in the ability to specifically reduce the diffusion resistance of the membrane bulk and the membrane-solution interface resistance through material modification and structural optimization. For example, researchers modified GO nanosheets with ionic liquids, which reduced the membrane resistance from 23 KΩ to 13 KΩ, a reduction of 43.4%, and increased the power density from 3.6 W / m² to 6.7 W / m², an increase of 86.1%. In another study, by etching holes on the surface of GO nanosheets, the membrane resistance was reduced from 40 KΩ to 30 KΩ, a reduction of 25%, and the power density was increased from 2 W / m² to 4.53 W / m², an increase of 127.0%.

[0005] While the aforementioned structural optimization and material modification efforts have made significant progress in reducing ion transport resistance and increasing membrane power density, these goals remain constrained by deep-seated physical mechanisms. They are largely limited to macroscopic optimization of channel geometry parameters such as size, pore size, and porosity, without a thorough analysis of the interfacial interaction dynamics between ions and channel walls within the sub-nanometer confined space. Microscopic resistance mechanisms, such as ion adsorption-desorption resistance, hydrated ion desolvation resistance, and charge repulsion resistance, remain unresolved. This results in significant microscopic resistance losses during ion transport within the confined channel, leading to a substantial gap between actual ion transport efficiency and theoretical low-resistance transport efficiency. This lack of understanding of microscopic transport resistance mechanisms prevents existing angstrom-scale channel membranes from achieving efficient, low-resistance ion transport, hindering breakthroughs in power density improvement and ultimately limiting the large-scale application of salinity gradient energy. Summary of the Invention

[0006] This invention provides a method for preparing a dehydrated drag-reducing ion exchange membrane, the resulting membrane, and its applications. The preparation process is simple, controllable, and widely applicable. The resulting dehydrated drag-reducing ion exchange membrane can achieve significantly improved power density output, showing broad development prospects in industrial applications such as salinity gradient power generation.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows.

[0008] A method for preparing a dehydration-reducing drag-reducing ion exchange membrane involves surface modification using a modifier followed by membrane formation. The modifier is a compound capable of stripping the hydration shell of target ions through specific binding or spatial confinement, selected from hydrocarbons: straight-chain alkanes, cycloalkanes, aromatic hydrocarbons, branched alkanes, macrocyclic cupule hydrocarbons, gourd-shaped macrocyclic hydrocarbons, and cyclic oligosaccharide hydrocarbons; ethers: cyclic monocyclic ethers, bicyclic / polycyclic cage ethers, chain polyethers, and cyclic / mixed ethers; amino acids: acidic amino acids, basic amino acids, and hydroxyl / phenolic hydroxyl amino acids; and at least one superionic conductor. The precursor is a two-dimensional nanosheet and / or monomer. The modifier enables the target ions to be transported within the membrane in a near-naked ion form, achieving dehydration-type ion migration.

[0009] Optionally, the modifier is selected from straight-chain alkanes: n-hexane, n-heptane, n-octane, and n-decane; cycloalkanes: cyclohexane, methylcyclohexane, and ethylcyclohexane; aromatic hydrocarbons: toluene, o-xylene, p-xylene, and ethylbenzene; branched-chain alkanes: isooctane (2,2,4-trimethylpentane) and isoheptane; macrocyclic calix hydrocarbons: calix[4]arene, calix[6]arene, p-tert-butylcalix[4]arene-tetraacetate, calixpyrrole[4]arene, and 4-sulfonylcalix[4]arene. Cucurbit-shaped macrocyclic hydrocarbons: cucurbit[5]urea, cucurbit[6]urea and cucurbit[7]urea; cyclic oligosaccharide hydrocarbons: α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin; cyclic monocyclic ethers: 18-crown-6, 15-crown-5, 12-crown-4, dibenzo-18-crown-6 and dicyclohexyl-18-crown-6; bicyclic / polycyclic cage ethers: [2.2.2]-cavitary ethers and [2.1.1]-cavitary ethers; chain polyethers: diethylene glycol, PEG-200, PEG-400 and PEG-600; cyclic / mixed ethers: tetrahydrofuran (THF), 1,4-dioxane and anisole; amino acids: aspartic acid, glutamic acid, lysine, tyrosine and serine; superionic conductors: Na3V2(P 1-x B x O4)3、Na3Zr2Si2PO 12 , Na3TiMn (PO4)3 and Na 3.83 V 1.17 Mn 0.58 Ni 0.25 At least one of (PO4)3.

[0010] Optionally, the precursor is a two-dimensional nanosheet, which is dispersed in water to form a dispersion with a concentration of 0.2-10 g / L; the dispersion is mixed with a modifier solution and stirred for 1-12 h, the pH is adjusted, and then filtered to form a membrane, which is then dried to obtain the dehydration drag-reducing ion exchange membrane; wherein the mass of the modifier is 1%-200% of the mass of the two-dimensional nanosheet.

[0011] Optionally, the two-dimensional nanosheets are at least one of graphene oxide, MXenes, two-dimensional nanosheets of metal oxides, two-dimensional nanosheets of transition metal sulfides, two-dimensional nanosheets of clay other than hydrotalcite, and two-dimensional nanosheets of elemental phosphorus. The mass of the modifier is 5%-100% of the mass of the two-dimensional nanosheets, and the pH is adjusted to 9-12.

[0012] In the filtration preparation of dehydration and drag-reducing ion exchange membranes, ultrasonic treatment is a key step to ensure the uniform dispersion of two-dimensional nanosheets. In some specific implementations, the ultrasonic time needs to be controlled at more than 5 minutes, with a typical operating range of 5 to 50 minutes, specifically 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 40 minutes, 50 minutes, etc.

[0013] The power of the ultrasonic treatment can be controlled between 100-500W, for example, specific values ​​such as 100W, 150W, 200W, 250W, 300W, 350W, 400W, 450W, 500W, etc., and a range with any two of the above specific values ​​as endpoints.

[0014] In the preparation of dehydration and drag-reducing ion exchange membranes, the surface charge distribution of the precursor can be optimized by adjusting the pH value of the mixture of dispersion and modifier solution, ensuring the material dispersion stability and interface modification effect. Alkali modifiers include sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), magnesium hydroxide (Mg(OH)2), and ammonia (NH3), etc., with sodium hydroxide or potassium hydroxide being selected as examples.

[0015] The above-described filtration process removes excess moisture from the intermediate membrane material through drying. In some specific embodiments, the drying temperature can be 30-60°C, and the drying time can be 30-240 minutes.

[0016] Optionally, the MXenes include Ti3C2T x The metal oxides include one or more of the following: Ti₂C, Ti₂N, Nb₂C, V₂C, Mo₂C, MnB, Fe₂B₂, MoB, and Cr₂B₂; the transition metal sulfides include WS₂ and MoS₂; the clays include one or more of the following: montmorillonite, mica, zeolite, kaolinite, and vermiculite; and the elemental phosphorus includes black phosphorus and / or purple phosphorus.

[0017] Optionally, the two-dimensional nanosheet may have 1-5 layers, specifically a single layer (1 layer), a few layers (2 layers, 3 layers), etc.

[0018] Optionally, the precursor is a monomer, and the preparation method includes introducing the modifier into a membrane material prepared from the monomer, wherein the mass of the modifier is 1%-100% of the mass of the monomer.

[0019] Optionally, the monomer is at least one of MOF monomer, COF monomer, hydrogel monomer, polyionic liquid monomer, and polyterephthalamide nanofibers. The hydrogel monomer is at least one of sodium alginate, chitosan, polyacrylamide, polyacrylic acid, polyethylene glycol, polyvinyl alcohol, and poly(2-methacrylate phosphate hydroxyethyl ester); the polyionic liquid monomer is at least one of polycyclic quaternary ammonium salt, poly[3-cyanomethyl-1-vinylimidazolium bis(trifluoromethanesulfonyl)imide], poly(1-vinyl-3-ethylimidazolium bromide), poly(methacryloyloxyethyltrimethylammonium chloride), poly(vinylbenzylsulfonic acid triethylammonium salt), poly(1,2-divinylimidazolium dibromide), and poly(diallyldimethylammonium chloride); the MOF monomer is, for example, ZIF-8 or MIL-101; the COF monomer is, for example, COF-366-Co or COF-1.

[0020] Optionally, the monomer forming membrane material can be formed by interfacial polymerization, solution casting, photopolymerization, etc. The modifier can be introduced by mixing the monomer precursor solution or dispersion with the modifier solution to form a membrane; or by immersing the membrane material in the modifier solution after monomer membrane formation.

[0021] Optionally, before or after the introduction of the modifier, the step of soaking the membrane material in an alkaline solution may be included.

[0022] A dehydration and drag-reducing ion exchange membrane is prepared using the above-described preparation method.

[0023] When the precursor is a two-dimensional nanosheet, the thickness of the dehydration and drag-reducing ion exchange membrane is 1-10 μm, more preferably 1-8 μm. This thickness control stems from the directional stacking behavior of the two-dimensional nanosheet precursor during the filtration process, forming a composite membrane with an ordered layered structure through interlayer self-assembly. This structure constructs a two-dimensional nanoscale fluid channel network within the membrane, providing a confined mass transfer pathway for efficient ion migration. This is a key structural basis for achieving high ion flux, thereby significantly enhancing power generation efficiency.

[0024] When the precursor is a monomer, the thickness of the dehydration and drag reduction type ion exchange membrane is 1-50 μm. The polymer membrane has flexible structural designability and excellent molding and processing performance. By controlling the pore distribution, hydrophilic and hydrophobic properties and functional group grafting rate of the membrane material, high ion flux and precise ion sieving can be achieved simultaneously, significantly improving power generation efficiency.

[0025] A permeation energy generating membrane, comprising or made of the above-mentioned dehydration drag-reducing ion exchange membrane.

[0026] The present invention also provides the application of the above-mentioned permeable energy-generating membrane in permeable energy harvesting in river-sea systems (such as river water-high salinity lake, river water-freshwater lake, etc.). For example, the above-mentioned permeable energy-generating membrane can be used as a reverse ion exchange membrane for permeable energy harvesting at river estuaries.

[0027] The beneficial effects of this invention include:

[0028] The strong binding sites on the modifier exhibit ion-ion binding forces far exceeding those between water molecules and ions, or possess pores with geometric dimensions smaller than hydrated ions. This "pulls" ions out of the hydrated shell, allowing them to escape the binding of hydrated molecules and be transported as bare ions within the two-dimensional nanofluidic channels of the membrane. Compared to ions carrying a hydrated shell, the spatial size of bare ions is significantly reduced, resulting in a substantial decrease in the contact area with the channel walls during migration. This greatly weakens the frictional resistance between ions and the channel, achieving low-resistance and high-efficiency ion transport. Simultaneously, the introduction of the modifier provides additional surface charge, enhancing the membrane's ion-sieving capacity. The preparation method is simple, highly operable, and applicable to various precursors, possessing industrial-scale production potential. The resulting membrane material, as a core component for permeate energy power generation, can achieve an output power density exceeding 5 W / m² (0.5 M / 0.01 M NaCl system), breaking through the bottleneck of permeate energy conversion efficiency in traditional membrane materials. Furthermore, as a high-performance reverse electrodialysis ion exchange membrane, it is suitable for salinity gradient energy capture systems at river-seawater confluences, providing an efficient technological path for renewable energy development.

[0029] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0030] Figure 1 The dehydration and drag reduction type ion exchange membrane (Ti3C2T) prepared in Example 1 x Cross-sectional microstructure of a two-dimensional nanosheet film material.

[0031] Figure 2 The dehydration and drag reduction type ion exchange membrane (Ti3C2T) prepared in Example 1 x Surface potential distribution of a two-dimensional nanosheet film material.

[0032] Figure 3 The dehydration and drag reduction type ion exchange membrane (Ti3C2T) prepared in Example 1 x (Based on two-dimensional nanosheet film material) and pure Ti3C2T in Comparative Example 1 xIV curve of membrane material.

[0033] Figure 4 The dehydration and drag reduction type ion exchange membrane (Ti3C2T) prepared in Example 1 x Output power density curve of the two-dimensional nanosheet film material.

[0034] Figure 5 The dehydration and drag reduction type ion exchange membrane (Ti3C2T) prepared in Example 1 x Current density curves of two-dimensional nanosheet film materials. Detailed Implementation

[0035] In order to provide a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.

[0036] The two-dimensional Ti3C2T used in the embodiments x The nanosheets can be commercially available or homemade. The specific preparation method is as follows: 1 gram of lithium fluoride (LiF) is slowly dissolved in 20 ml of 9 M hydrochloric acid (HCl) solution to form an etching system. Then, 1 gram of Ti3AlC2 MAX phase powder is added to this system, and etching is completed at room temperature with magnetic stirring at 300 rpm for 24 hours. The resulting acidic slurry is washed 5-8 times by centrifugation with ultrapure water at 3500 rpm until the pH of the supernatant is stably above 6.0. Finally, under the protection of an ice-water bath and argon atmosphere, the precipitate is redispersed in ultrapure water, ultrasonicated (500 W) for 30 minutes, and then centrifuged at 5000 rpm for 30 minutes. The upper colloidal dispersion is collected as Ti3C2Tx nanosheets, with 1-3 layers. This process uses argon protection to suppress oxidation side reactions and ensure the structural integrity of the nanosheets.

[0037] The characterization methods and instruments used in the examples are described below:

[0038] Microstructure characterization: SUPRA 55 field emission scanning electron microscope. Fabrication process: quenching in liquid nitrogen.

[0039] Surface potential distribution measurement: Cypher ES atomic force microscope, Asylum Research. Test mode: point contact, probe: NSC18 / Pt.

[0040] Output power density test: KEITHEY 2400. Test area: 0.03 mm² 2 Test temperature: 25℃, electrolyte: 0.01 M / 0.5 M NaCl solution.

[0041] Example 1

[0042] This embodiment provides a method for preparing a dehydration and drag-reducing ion exchange membrane, the method comprising:

[0043] Take a certain mass of MXene (Ti3C2T) x Nanosheets were dispersed in deionized water at a concentration of 5 g / L, and then subjected to ultrasonic treatment at 500W for 40 minutes to achieve uniform dispersion, yielding Ti3C2T. x Two-dimensional nanosheet dispersion. Take 1 ml of Ti3C2T. x The two-dimensional nanosheet dispersion was then mixed with a 4-sulfonylcalix[4]arene solution containing 10% MXene by mass, and mechanically stirred for 360 minutes. The pH of the suspension was adjusted to 11.0 with sodium hydroxide (NaOH), and the solvent was filtered using a vacuum filtration device to form a wet film. The wet film was vacuum dried at 60°C for 2 hours to remove residual moisture, and the resulting Ti3C2T was obtained after peeling. x The two-dimensional nanosheet membrane material is a dehydration and drag-reducing ion exchange membrane.

[0044] Comparative Example 1

[0045] A method for preparing a two-dimensional nanosheet film material, which differs from Example 1 in that no modifier is added, and the specific preparation method includes the following steps:

[0046] A certain mass of MXene nanosheets was dispersed in deionized water at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain Ti3C2T. x Two-dimensional nanosheet dispersion. Take 1 ml of Ti3C2T. x A two-dimensional nanosheet dispersion was prepared, and the pH of the suspension was adjusted to 11.0 with sodium hydroxide (NaOH). The solvent was then filtered using a vacuum filtration device to form a wet membrane. The wet membrane was vacuum dried at 60°C for 2 hours to remove residual moisture, and the membrane was then peeled off to obtain the ion exchange membrane material.

[0047] The MXene two-dimensional nanosheet film material prepared in Comparative Example 1 was characterized. The results showed that the MXene nanosheets, after vacuum filtration, assembled into a stacked two-dimensional nanosheet film material with an average potential of approximately 187 mV; the film resistivity of the MXene-based two-dimensional nanosheet film material was 40 kΩ, and the output power density in a NaCl electrolyte with a 50-fold gradient was 3.86 W / m². 2 .

[0048] The Ti3C2T prepared in Example 1 x The two-dimensional nanosheet film material was characterized, and the results are as follows:

[0049] Depend on Figure 14-sulfonylcalix[4]arene-modified Ti3C2T can be observed x After being vacuum filtered, the nanosheets are assembled into a layer-by-layer dehydration and drag-reducing ion exchange membrane. The thickness of the dehydration and drag-reducing ion exchange membrane in Example 1 is about 6.29 μm, and it has a dense two-dimensional nanofluid channel, which provides a structural basis for the rapid migration of ions.

[0050] Figure 2 The Ti3C2T prepared in this embodiment x The surface potential distribution of the two-dimensional nanosheet film material is shown in the figure. The prepared Ti3C2T can be observed from this figure. x The base permeation energy-generating membrane material has a uniformly distributed potential with an average potential of approximately 347 mV. The stable potential distribution effectively ensures the directionality and continuity of ion migration.

[0051] Figure 3 The 4-sulfonylcalix[4]aromatic modified Ti3C2T of Example 1 x Membrane and pure Ti3C2T of Comparative Example 1 x The IV curve of the membrane without external resistance shows that the 4-sulfonyl calix [4] aromatic modified Ti3C2T prepared in Example 1... x After modification with a modifier, the membrane exhibits improved voltage and current, with a permeation current as high as 9.32 μA. Simultaneously, the membrane resistance decreased from approximately 40 kΩ to 12 kΩ, a reduction of 70.0%, achieving low-resistance and high-efficiency ion transport.

[0052] The test method was as follows: data were collected using a KEITHEY 2400 electrochemical workstation. The electrode pair was Ag / AgCl; the electrolyte was NaCl solution of different concentrations; the permeation membrane was the 4-sulfonylcalix[4] aromatic modified Ti3C2T prepared in Example 1. x The membrane has an area of ​​0.03 mm. 2 The above was tested using an H-type electrochemical cell. The effects of moisture evaporation and air absorption were minimized during testing. Test conditions were: -0.2 V to 0.2 V, scan rate: 0.01 V / s. Ion transport behavior and salt gradient conversion were analyzed, and output power performance was evaluated using a variable external resistor. Results are as follows: Figure 4 As shown.

[0053] Figure 4 Ti3C2T prepared in Example 1 x Output power density curve of two-dimensional nanosheet film material, Figure 5 Ti3C2T prepared in Example 1 x The current power density curve of the two-dimensional nanosheet film material shows that the 4-sulfonyl calix [4] aromatic modified Ti3C2T prepared in Example 1x The two-dimensional nanofluidic channels in the membrane exhibit excellent power generation performance, with an output power density reaching 9.8 W / m². 2 The current density is 137 A / m. 2 .

[0054] Example 2

[0055] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0056] A certain mass of GO nanosheets was dispersed in deionized water at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain a GO-based two-dimensional nanosheet dispersion. One ml of the GO-based two-dimensional nanosheet dispersion was then added to a 15-crown-5 solution (10% of the GO mass), and the mixture was mechanically stirred for 420 minutes. The pH of the suspension was adjusted to 11.0 with potassium hydroxide (KOH), and the solvent was filtered using a vacuum filtration device to form a wet membrane. The wet membrane was vacuum dried at 60℃ for 2 hours to remove residual moisture. After peeling, a dehydrated drag-reducing ion exchange membrane was obtained. A membrane without any modifiers and under identical conditions was used as a control sample.

[0057] The 15-crown-5 / GO two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that GO nanosheets, after vacuum filtration, assembled into a stacked GO-based two-dimensional nanosheet membrane material, which possesses dense two-dimensional nanofluidic channels. Compared to the membrane without modifiers, the prepared GO-based two-dimensional nanosheet membrane material exhibits a uniformly distributed potential with an average potential of approximately 313 mV, representing an increase in average membrane potential. The resistivity of the modified membrane material decreased dramatically from 32 kΩ to 18 kΩ, a reduction of 43.8%. The prepared GO-based two-dimensional nanosheet membrane material achieved a power density of 8.9 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0058] Example 3

[0059] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0060] A certain mass of montmorillonite nanosheets was dispersed in deionized water at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain a montmorillonite-based two-dimensional nanosheet dispersion. 1 ml of this dispersion was then added to a 15-crown-5 solution (10% of the mass of montmorillonite), and the mixture was mechanically stirred for 360 minutes. The pH of the suspension was adjusted to 9.0 with sodium hydroxide (NaOH), and the solvent was filtered using a vacuum filtration device to form a wet membrane. The wet membrane was vacuum dried at 60℃ for 2 hours to remove residual moisture. After peeling, a dehydrated drag-reducing ion exchange membrane was obtained. A membrane without any modifiers and under identical conditions was used as a control sample.

[0061] The 15-crown-5 / montmorillonite two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that the montmorillonite nanosheets, after vacuum filtration, assembled into a layer-by-layer stacked montmorillonite-based two-dimensional nanosheet membrane material, which possesses dense two-dimensional nanofluid channels. Compared to the membrane without modifiers, the prepared montmorillonite-based two-dimensional nanosheet membrane material exhibits a uniformly distributed potential with an average potential of approximately 260 mV, representing an increase in average membrane potential. The resistivity of the modified membrane material achieved a significant reduction, decreasing dramatically from 45 kΩ to 15 kΩ, a resistance reduction of 66.7%. The prepared montmorillonite-based two-dimensional nanosheet membrane material achieved a power density of 7.2 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0062] Example 4

[0063] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0064] A certain mass of black phosphorus nanosheets was dispersed in deionized water at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain a black phosphorus-based two-dimensional nanosheet dispersion. 1 ml of the black phosphorus-based two-dimensional nanosheet dispersion was taken, and then a γ-cyclodextrin solution with a solute mass of 10% of the black phosphorus mass was added. The mixture was mechanically stirred for 120 minutes. The pH of the suspension was adjusted to 11.0 with sodium hydroxide (NaOH), and the solvent was filtered using a vacuum filtration device to form a wet membrane. The wet membrane was vacuum dried at 60℃ for 2 hours to remove residual moisture. After peeling, a dehydrated drag-reducing ion exchange membrane was obtained. A membrane without any modifiers and under identical conditions was used as a control sample.

[0065] The γ-cyclodextrin / black phosphorus two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that the black phosphorus nanosheets, after vacuum filtration, assembled into a stacked black phosphorus-based two-dimensional nanosheet membrane material, which possessed dense two-dimensional nanofluid channels. Compared to the membrane without modifiers, the prepared black phosphorus-based two-dimensional nanosheet membrane material exhibited a uniformly distributed potential with an average potential of approximately 297 mV, representing an increase in average membrane potential. The resistivity of the modified membrane material decreased dramatically from 37 kΩ to 16.2 kΩ, a reduction of 56.2%. The prepared black phosphorus-based two-dimensional nanosheet membrane material achieved a power density of 8.3 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0066] Example 5

[0067] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0068] A certain mass of MnO2 nanosheets was dispersed in N-methylpyrrolidone at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain a MnO2-based two-dimensional nanosheet dispersion. 1 ml of the MnO2-based two-dimensional nanosheet dispersion was taken, and then a p-tert-butylcalix[4] aromatic solution with a solute mass of 10% of MnO2 was added. The mixture was mechanically stirred for 720 minutes. The pH of the suspension was adjusted to 10.0 with sodium hydroxide (NaOH), and the solvent was filtered using a vacuum filtration device to form a wet membrane. The wet membrane was vacuum dried at 60°C for 4 hours to remove residual solvent. After peeling, a dehydrated drag-reducing ion exchange membrane was obtained. A membrane without any modifier and with all other conditions being the same was used as a control sample.

[0069] The tert-butylcalix[4]arene / MnO2 two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that after vacuum filtration, the MnO2 nanosheets were assembled into a layer-by-layer stacked MnO2-based two-dimensional nanosheet membrane material, which has dense two-dimensional nanofluid channels. Compared with the membrane without the addition of the modifier, the prepared MnO2-based two-dimensional nanosheet membrane material has a uniformly distributed potential, with an average potential of about 315 mV, and the average potential of the membrane is improved; the resistance of the modified membrane material has achieved a leapfrog decrease, from 30 kΩ to 19.5 kΩ, with a resistance reduction of 35%; the output power density of the prepared MnO2-based two-dimensional nanosheet membrane material in a NaCl electrolyte with a 50-fold gradient can reach 8.2 W / m 2 .

[0070] Example 6

[0071] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0072] Take a certain mass of MXene (Ti3C2T) x Ti3C2Tx-based two-dimensional nanosheets were dispersed in N-methylpyrrolidone at a concentration of 5 g / L and subjected to ultrasonic treatment at 500 W for 40 minutes to achieve uniform dispersion, yielding a Ti3C2Tx-based two-dimensional nanosheet dispersion. 0.4 ml of Ti3C2Tx was then used. x Two-dimensional nanosheet dispersions were prepared, followed by the addition of cucurbita urea solution with a solute mass of 10% of MXene [5], and mechanically stirred for 720 minutes. The pH of the suspension was adjusted to 12.0 with sodium hydroxide (NaOH), and the solvent was filtered using a vacuum filtration device to form a wet membrane. The wet membrane was vacuum dried at 60°C for 4 hours to remove residual solvent, and after peeling, a dehydrated drag-reducing ion exchange membrane was obtained. A membrane without modifiers and with all other conditions being the same was used as a control sample.

[0073] The cucurbita[5]urea / MXene two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that after vacuum filtration, the MXene nanosheets were assembled into a layer-by-layer stacked MXene-based two-dimensional nanosheet membrane material, which has dense two-dimensional nanofluid channels. Compared with the membrane without the addition of the modifier, the prepared MXene-based two-dimensional nanosheet membrane material has a uniformly distributed potential with an average potential of about 280 mV, and the average potential of the membrane is improved; the resistance of the modified membrane material achieved a leapfrog decrease, from 40 kΩ to 13.8 kΩ, with a resistance reduction of 65.5%; the prepared MXene-based two-dimensional nanosheet membrane material can achieve an output power density of 7.5 W / m in a NaCl electrolyte with a 50-fold gradient. 2 .

[0074] Example 7

[0075] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0076] A certain mass of GO nanosheets was dispersed in deionized water at a concentration of 1 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain a GO-based two-dimensional nanosheet dispersion. 3 ml of the GO-based two-dimensional nanosheet dispersion was taken, and then 16-crown-6 solution (20% by mass of GO) was added. The mixture was mechanically stirred for 120 minutes. The pH of the suspension was adjusted to 9.0 with sodium hydroxide (NaOH), and the solvent was filtered using a vacuum filtration device to form a wet membrane. The wet membrane was vacuum dried at 60℃ for 2 hours to remove residual moisture. After peeling, a dehydrated drag-reducing ion exchange membrane was obtained. A membrane without any modifiers and under identical conditions was used as a control sample.

[0077] The 16-crown-6 / GO two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that GO nanosheets, after vacuum filtration, assembled into a stacked GO-based two-dimensional nanosheet membrane material, which possesses dense two-dimensional nanofluidic channels. Compared to the membrane without modifiers, the prepared GO-based two-dimensional nanosheet membrane material exhibits a uniformly distributed potential with an average potential of approximately 308 mV, representing an increase in average membrane potential. The resistivity of the modified membrane material decreased dramatically from 32 kΩ to 21.5 kΩ, a reduction of 32.8%. The prepared GO-based two-dimensional nanosheet membrane material achieved a power density of 8.0 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0078] Example 8

[0079] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0080] A certain mass of MoS2 nanosheets was dispersed in deionized water at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain a MoS2-based two-dimensional nanosheet dispersion. 0.6 ml of the MoS2-based two-dimensional nanosheet dispersion was taken, and then 12% (by weight of MoS2) of 16-crown-6 solution was added. The mixture was mechanically stirred for 360 minutes. The pH of the suspension was adjusted to 11.0 with sodium hydroxide (NaOH), and the solvent was filtered using a vacuum filtration device to form a wet membrane. The wet membrane was vacuum dried at 60℃ for 2 hours to remove residual moisture. After peeling, a dehydrated drag-reducing ion exchange membrane was obtained. A membrane without any modifiers and under identical conditions was used as a control sample.

[0081] The 16-crown-6 / MoS2 two-dimensional nanosheet film material prepared in this embodiment was characterized. The results showed that the MoS2 nanosheets, after vacuum filtration, assembled into a stacked MoS2-based two-dimensional nanosheet film material with dense two-dimensional nanofluid channels. Compared to the unmodified film, the prepared MoS2-based two-dimensional nanosheet film material exhibited a uniformly distributed potential with an average potential of approximately 315 mV, representing an increase in average potential. The resistivity of the modified film material decreased dramatically from 35 kΩ to 20 kΩ, a reduction of 42.9%. The prepared MoS2-based two-dimensional nanosheet film material achieved a power density of 7.8 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0082] Example 9

[0083] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0084] A certain mass of GO nanosheets was dispersed in deionized water at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain a GO-based two-dimensional nanosheet dispersion. One ml of the GO-based two-dimensional nanosheet dispersion was then added to a serine solution with a solute concentration of 60% of the GO mass, and the mixture was mechanically stirred for 420 minutes. The pH of the suspension was adjusted to 11.0 with potassium hydroxide (KOH), and the solvent was filtered using a vacuum filtration device to form a wet membrane. The wet membrane was vacuum dried at 60℃ for 2 hours to remove residual moisture, and after peeling, a dehydrated drag-reducing ion exchange membrane was obtained. A membrane without any modifiers and under identical conditions was used as a control sample.

[0085] The serine / GO two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that GO nanosheets, after vacuum filtration, assembled into a stacked GO-based two-dimensional nanosheet membrane material, which possesses dense two-dimensional nanofluidic channels. Compared to the membrane without modifiers, the prepared GO-based two-dimensional nanosheet membrane material exhibits a uniformly distributed potential with an average potential of approximately 266 mV, representing an increase in average membrane potential. The resistivity of the modified membrane material experienced a significant reduction, decreasing dramatically from 32 kΩ to 17 kΩ, a resistance reduction of 46.9%. The prepared GO-based two-dimensional nanosheet membrane material achieved a power density of 7.3 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0086] Example 10

[0087] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0088] A certain mass of montmorillonite nanosheets was dispersed in deionized water at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes, resulting in a montmorillonite-based two-dimensional nanosheet dispersion. One ml of this dispersion was taken, and the pH was adjusted to 11 with potassium hydroxide. The solvent was then filtered through a vacuum filter to form a wet film. A film without any modifier and under identical conditions was used as a control sample.

[0089] 3 mmol sodium acetate, 1 mmol tetraisopropyl titanate, 1 mmol manganese acetate, and 1 mmol citric acid were dissolved in 80 mL ethanol to form solution A; 3 mmol ammonium dihydrogen phosphate was dissolved in 10 mL deionized water to form solution B. Under stirring at 80 °C, solution B was added dropwise to solution A to form an emulsion suspension. Stirring continued until the solvent evaporated, and the solid precursor was collected. The precursor was pre-calcined at 350 °C for 4 hours in an argon (Ar) atmosphere (to remove organic impurities), and then annealed at 650 °C for 4 hours to finally obtain the target sodium superionic conductor structure material. The sodium superionic conductor material was ground and mixed with Nafion and super P in an 8:1:1 ratio to form a slurry. This slurry was then coated onto dried montmorillonite using a spatula, and after drying, a dehydrated drag-reducing ion exchange membrane was obtained. A membrane without modifiers and under identical conditions was used as a control sample.

[0090] The sodium superionic conductor / montmorillonite two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that the montmorillonite nanosheets, after vacuum filtration, assembled into a layer-by-layer stacked montmorillonite-based two-dimensional nanosheet membrane material, which possesses dense two-dimensional nanofluid channels. Compared to the membrane without modifiers, the prepared montmorillonite-based two-dimensional nanosheet membrane material exhibits a uniformly distributed potential with an average potential of approximately 260 mV, representing an increase in average membrane potential. The resistivity of the modified membrane material achieved a significant reduction, decreasing dramatically from 45 kΩ to 25 kΩ, a resistance reduction of 44.4%. The prepared montmorillonite-based two-dimensional nanosheet membrane material achieved a power density of 6.6 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0091] Example 11

[0092] This embodiment provides a dehydration and drag-reducing ion exchange membrane, the preparation method of which includes:

[0093] 52.2 mmol TPA was dissolved in 7 mL of ethyl acetate to prepare a TPA-ethyl acetate solution; mesitylene and n-hexane were mixed at a volume ratio of 1:3 to obtain a mesitylene solution with a volume percentage of 25%. 131.4 mmol TAM and 5 mmol sulfonated calix[4] aromatics were dispersed in 7 mL of 1M acetic acid aqueous solution. Then, the TPA-ethyl acetate solution containing 52.2 mmol TPA and 7 mL of 25% mesitylene solution were gently placed on top of the TAM and stored at 35°C for 3 days. After washing with ethanol and water in sequence, the membrane was immersed in 1M sodium hydroxide solution for 1 h to obtain the sulfonated calix[4] aromatics / COF membrane material as a dehydration drag-reducing ion exchange membrane. The membrane without the addition of modifier and under the same other conditions was used as a control sample.

[0094] The sulfonated cup [4] aromatic hydrocarbon / COF membrane material prepared in this embodiment was characterized. The results showed that, compared with the membrane without the modifier, the prepared COF membrane material had a uniformly distributed potential with an average potential of about 320 mV, and the average membrane potential was improved; the resistance of the modified membrane material achieved a leapfrog decrease, from 42 kΩ to 18 kΩ, with a resistance reduction of 57.1%; the prepared COF membrane material could achieve an output power density of 9.2 W / m in a NaCl electrolyte with a 50-fold gradient. 2 .

[0095] Example 12

[0096] A method for preparing a dehydration and drag-reducing ion exchange membrane includes the following steps:

[0097] 2 g of Kevlar yarn and 2 g of KOH were added to 100 mL of dimethyl sulfoxide. The mixture was magnetically stirred at room temperature for 1 week to obtain a KANF dispersion. Then the obtained KANF and 1.68 mmol of 4-sulfonylcalix[4] aromatic hydrocarbon were dissolved in DMSO, and the dispersion was cast onto a 0.1 μm organic nylon substrate. After vacuum drying, the KANF membrane could be easily removed from the substrate to form an ultrathin and independent KANF intermediate membrane. The membrane was then immersed in 1M sodium hydroxide solution for 1 h, and then rinsed and dried with deionized water. KANF stands for Kevlar Nanofibers. The KANF dispersion is a dispersion of Kevlar nanofibers. The membrane without modifiers and under the same conditions was used as a control sample.

[0098] The modified poly(terephthalamide) nanofiber membrane material prepared in this embodiment was characterized. The results showed that, compared to the membrane without the modifier, the prepared Kevlar nanofiber membrane material exhibited a uniformly distributed potential with an average potential of approximately 315 mV, indicating an increase in average membrane potential. The resistivity of the modified membrane material decreased dramatically from 30 kΩ to 13 kΩ, a reduction of 56.7%. The prepared Kevlar nanofiber membrane material achieved a power density of 8.1 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0099] Example 13

[0100] A method for preparing a dehydration and drag-reducing ion exchange membrane includes the following steps:

[0101] 1 g of poly[3-cyanomethyl-1-vinylimidazolium bis(trifluoromethanesulfonyl)imide] with a molecular weight of 115,000 and 0.18 g of polyacrylic acid with a molecular weight of 2,000 were mixed in a specific ratio and dissolved in an N,N-dimethylformamide solution. The mixture was then poured onto a glass plate in an oven. The solvent was completely removed by vacuum drying at 80 °C. Subsequently, after cooling to room temperature, the membrane was soaked in 28% ammonia solution (pH ≈ 10) for 2 hours to obtain an intermediate membrane. The intermediate membrane was then soaked in a 1 mol / L solution of 15-crown-5 for 12 hours. After removal, the membrane surface was rinsed with deionized water, and the membrane was dried in a vacuum oven at 60 °C for 2 hours to remove excess water, thus obtaining a dehydration-reducing drag-reducing ion exchange membrane, denoted as the modified polyionic liquid-based ion exchange membrane. A membrane without any modifier and under the same conditions was used as a control sample.

[0102] The polyionic liquid-based ion exchange membrane material prepared in this embodiment was characterized. The results showed that, compared to the membrane without modifier, the prepared polyionic liquid membrane material exhibited a uniformly distributed potential with an average potential of approximately 280 mV, indicating an increase in average membrane potential. The resistivity of the modified membrane material decreased dramatically from 28 kΩ to 14 kΩ, a reduction of 50.0%. The prepared membrane material achieved a power density of 7.9 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0103] Example 14

[0104] A method for preparing a dehydration and drag-reducing ion exchange membrane includes the following steps:

[0105] PVP was dissolved in N-methylpyrrolidone to form a 5 wt% transparent solution. Then, a precursor solution was prepared by mixing HEMAP, HEMA, LMA, BIS, PEGDMA, PVP solution, and DEOP. Photopolymerization was carried out by ultraviolet irradiation using a PL-LED100 light source at a wavelength of 365 nm to obtain a HEMAP hydrogel interlayer. The HEMAP hydrogel interlayer was immersed in a 1 mol / L γ-cyclodextrin solution for 12 h, then rinsed with deionized water and dried in a vacuum oven at 60 °C for 2 h to remove excess water, yielding a dehydrated drag-reducing ion exchange membrane, designated as the modified HEMAP hydrogel membrane. A membrane without modifiers, under identical conditions, served as a control.

[0106] The modified HEMAP hydrogel membrane material prepared in this embodiment was characterized. The results showed that, compared to the membrane without the modifier, the prepared hydrogel membrane material exhibited a uniformly distributed potential with an average potential of approximately 265 mV, indicating an improvement in the average membrane potential. The resistivity of the modified hydrogel membrane material experienced a significant reduction, decreasing dramatically from 20 kΩ to 10 kΩ, a resistance reduction of 50.0%. The prepared hydrogel membrane material achieved a power density of 7.4 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0107] Example 15

[0108] A method for preparing a dehydration and drag-reducing ion exchange membrane includes the following steps:

[0109] 1.68 mmol of zinc nitrate hexahydrate was dissolved in 20 mL of acetone to obtain a metal solution. 0.5 g of 2-methylimidazole was dissolved in 20 mL of acetone to obtain an organic ligand solution. The organic ligand solution was poured into the metal solution, the two solutions were mixed, and the mixture was stirred at 200 rpm at room temperature for 1 h. The nanoparticles were washed three times with fresh methanol using a centrifuge to remove unreacted substances to obtain ZIF-8. 2 mg of ZIF-8, 0.5 mg of 4-sulfonylcalix[4]arene and 8 mg of PVDF were dispersed in 10 mL of N-methylpyrrolidone. The slurry was stirred for 1 hour, and then coated onto a glass slide with a spatula. After drying, a dehydration drag-reducing ion exchange membrane was obtained, which was designated as the modified MOF membrane. The membrane without the modifier and under the same conditions was used as a control sample.

[0110] The modified MOF membrane material prepared in this embodiment was characterized. The results showed that, compared to the membrane without modifier, the prepared MOF membrane material exhibited a uniformly distributed potential with an average potential of approximately 310 mV, indicating an increase in average membrane potential. The resistivity of the modified MOF membrane material decreased dramatically from 46 kΩ to 19 kΩ, a reduction of 58.7%. The prepared MOF membrane material achieved a power density of 8.2 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0111] Comparative Example 2

[0112] This comparative example provides a two-dimensional nanosheet film material, the preparation method of which includes:

[0113] A certain mass of montmorillonite nanosheets was dispersed in deionized water at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain a montmorillonite-based two-dimensional nanosheet dispersion. 1 ml of this dispersion was then added to a 15-crown-5 solution (10% of the mass of montmorillonite), and the mixture was mechanically stirred for 30 minutes. The pH of the suspension was adjusted to 3 with hydrochloric acid, and the solvent was filtered through a vacuum filter to form a wet film. The wet film was vacuum dried at 60°C for 2 hours to remove residual moisture, and the resulting two-dimensional nanosheet membrane material was obtained after peeling. A membrane without any modifiers and under identical conditions was used as a control sample.

[0114] The 15-crown-5 / montmorillonite two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that the montmorillonite nanosheets, after vacuum filtration, assembled into a layer-by-layer stacked montmorillonite-based two-dimensional nanosheet membrane material, which possesses dense two-dimensional nanofluid channels. Compared to the membrane without modifiers, the prepared montmorillonite-based two-dimensional nanosheet membrane material exhibits a uniformly distributed potential with an average potential of approximately 205 mV, representing an increase in average membrane potential. The resistivity of the modified membrane material achieved a significant reduction, decreasing dramatically from 50 kΩ to 30 kΩ, a 40.0% decrease. The prepared montmorillonite-based two-dimensional nanosheet membrane material achieved a power density of 4.6 W / m³ in a NaCl electrolyte with a 50-fold gradient. 2 .

[0115] Comparative Example 3

[0116] This comparative example provides a two-dimensional nanosheet film material, the preparation method of which includes:

[0117] A certain mass of MXene nanosheets was dispersed in deionized water at a concentration of 5 g / L. The dispersion was achieved by ultrasonic treatment at 500 W for 40 minutes to obtain Ti3C2T. x Two-dimensional nanosheet dispersion. Take 1 ml of Ti3C2T. x A two-dimensional nanosheet dispersion was prepared, followed by the addition of a 4-sulfonylcalix[4] aromatic hydrocarbon solution containing 10% MXene by mass, and mechanically stirred for 30 minutes. The pH of the suspension was adjusted to 3 with hydrochloric acid, and the solvent was filtered using a vacuum filtration device to form a wet film. The wet film was vacuum dried at 60°C for 2 hours to remove residual moisture, and the two-dimensional nanosheet membrane material was obtained after peeling. A membrane without modifiers and with all other conditions being the same was used as a control sample.

[0118] The 4-sulfonylcalix[4]arene / MXene two-dimensional nanosheet membrane material prepared in this embodiment was characterized. The results showed that after vacuum filtration, the MXene nanosheets were assembled into a layer-by-layer stacked MXene-based two-dimensional nanosheet membrane material, which has dense two-dimensional nanofluid channels. Compared with the membrane without the addition of the modifier, the prepared MXene-based two-dimensional nanosheet membrane material has a uniformly distributed potential with an average potential of about 200 mV, and the average potential of the membrane is improved; the resistance of the modified membrane material achieved a leapfrog decrease, from 44 kΩ to 27 kΩ, with a resistance reduction of 38.6%; the prepared MXene-based two-dimensional nanosheet membrane material can achieve an output power density of 5.3 W / m in a NaCl electrolyte with a 50-fold gradient. 2 .

[0119] Table 1. Raw material information and performance test results of the dehydration drag-reducing ion exchange membranes of Examples 1-15 and the two-dimensional nanosheet membrane materials of Comparative Examples 1-3.

[0120] precursor Modifier pH value Average potential / mV Pre-modified film resistance / kΩ Modified film resistance / kΩ <![CDATA[Output power density W·m -2 > Example 1 MXene 4-Sulfocal[4]arene 11 347 40 12 9.8 Example 2 GO 15-crown-5 11 313 32 18 8.9 Example 3 Montmorillonite 15-crown-5 9 260 45 15 7.2 Example 4 Black phosphorus γ-Cyclodextrin 11 297 37 16.2 8.3 Example 5 <![CDATA[MnO2]]> p-tert-butylcalix[4] aromatics 10 315 30 19.5 8.2 Example 6 MXene Cucurbita[5]urea 12 280 40 13.8 7.5 Example 7 GO 16-crown-6 9 308 32 21.5 8.0 Example 8 <![CDATA[MoS2]]> 16-crown-6 11 315 35 20 7.8 Example 9 GO Serine 11 266 32 17 7.3 Example 10 Montmorillonite Sodium superionic conductor 11 260 45 25 6.6 Example 11 COF Sulfonated calix[4]arene / 320 42 18 9.2 Example 12 Kevlar nanofibers Sulfonated calix[4]arene / 315 30 13 8.1 Example 13 Ionic liquids 15-crown-5 / 280 28 14 7.9 Example 14 hydrogel γ-Cyclodextrin / 265 20 10 7.4 Example 15 MOF 4-Sulfocal[4]arene / 310 46 19 8.2 Comparative Example 1 MXene / 11 187 40 / 3.86 Comparative Example 2 Montmorillonite 15-crown-5 3 205 50 30 4.6 Comparative Example 3 MXene Sulfonated calix[4]arene 3 200 44 27 5.3

[0121] Table 1 summarizes the raw material conditions, modifiers, pH values, average potentials, membrane resistances before and after modification, and performance test results of membrane materials for Examples 1-15 and Comparative Examples 1-3. As can be seen from Table 1, the dehydration-reducing drag-reducing ion exchange membranes prepared in Examples 1-15 exhibit significantly lower membrane resistances compared to membranes without modifiers, while also possessing higher average potentials and output power, with output power consistently above 6.6 W / m. 2 The above describes the process; in Example 1, the highest average potential reached 347 mV, the resistance decreased by 28 kΩ compared to the unmodified film, the resistance change rate reached 70%, and the highest output power reached 9.8 W / m. 2 .

[0122] The dehydration-reducing drag-reducing ion exchange membranes in Examples 1-15 utilize dehydration modifiers to accelerate ion migration, resulting in output power far exceeding the industrial benchmark for river-seawater systems and surpassing the output power density of most advanced permeate energy-generating membrane materials. They can be used as permeate energy-generating membrane materials in reverse ion exchange membranes to collect permeate energy at river estuaries. Furthermore, their excellent power generation capacity, simple preparation process, and broad applicability make them suitable for industrial production and offer broad application prospects.

[0123] The above embodiments are only used to further illustrate a dehydration drag-reducing ion exchange membrane of the present invention, its preparation method and application. However, the present invention is not limited to the embodiments. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for preparing a dehydration and drag-reducing ion exchange membrane, characterized in that: The precursor is surface modified using a modifier, and then a film is formed using a film-forming process. The modifier is a compound capable of stripping the hydration shell of the target ion through specific binding or spatial confinement, and is selected from at least one of hydrocarbons, ethers, amino acids, and superionic conductors; wherein the hydrocarbons include straight-chain alkanes, cycloalkanes, aromatic hydrocarbons, branched alkanes, macrocyclic cupule hydrocarbons, gourd-shaped macrocyclic hydrocarbons, and cyclic oligosaccharide hydrocarbons; the ethers include cyclic monocyclic ethers, bicyclic / polycyclic cage ethers, chain polyethers, and cyclic / mixed ethers; and the amino acids include acidic amino acids, basic amino acids, and amino acids containing hydroxyl / phenolic hydroxyl groups. The precursor is a two-dimensional nanosheet and / or a monomer; The modifier enables the target ions to be transported within the membrane in the form of bare ions, thereby achieving dehydration-type ion migration.

2. The method for preparing the dehydration and drag-reducing ion exchange membrane according to claim 1, characterized in that: The straight-chain alkanes include n-hexane, n-heptane, n-octane, and n-decane; the cycloalkanes include cyclohexane, methylcyclohexane, and ethylcyclohexane; the aromatic hydrocarbons include toluene, o-xylene, p-xylene, and ethylbenzene; the branched-chain alkanes include isooctane (2,2,4-trimethylpentane) and isoheptane; the macrocyclic calix hydrocarbons include calix[4]arene, calix[6]arene, p-tert-butylcalix[4]arene-tetraacetate, calixpyrrole[4]arene, and 4-sulfonylcalix[4]arene; the cucurbit-shaped macrocyclic hydrocarbons include cucurbit[5]urea, cucurbit[6]urea, and cucurbit[7]urea; the cyclic oligosaccharide hydrocarbons include α-cyclodextrin, β-cyclodextrin, and β-cyclodextrin. The cyclic monocyclic ethers include 18-crown-6, 15-crown-5, 12-crown-4, dibenzo-18-crown-6, and dicyclohexyl-18-crown-6; the bicyclic / polycyclic cage ethers include [2.2.2]-cryptoethers and [2.1.1]-cryptoethers; the chain polyethers include diethylene glycol, PEG-200, PEG-400, and PEG-600; the cyclic / mixed ethers include tetrahydrofuran (THF), 1,4-dioxane, and anisole; the amino acids include aspartic acid, glutamic acid, lysine, tyrosine, and serine; the superionic conductors include Na3V2(P 1-x B x O4)3、Na3Zr2Si2PO 12 , Na3TiMn (PO4)3 and Na 3.83 V 1.17 Mn 0.58 Ni 0.25 (PO4)3.

3. The method for preparing the dehydration and drag-reducing ion exchange membrane according to claim 1, characterized in that: The precursor is a two-dimensional nanosheet. The two-dimensional nanosheet is dispersed in water to form a dispersion with a concentration of 0.2-10 g / L. The dispersion is mixed with a modifier solution and stirred for 1-12 h. After adjusting the pH, the mixture is filtered to form a membrane and dried to obtain the dehydration drag-reducing ion exchange membrane. The mass of the modifier is 1%-200% of the mass of the two-dimensional nanosheet.

4. The method for preparing the dehydration and drag-reducing ion exchange membrane according to claim 3, characterized in that: The two-dimensional nanosheets are at least one of graphene oxide, MXenes, two-dimensional nanosheets of metal oxides, two-dimensional nanosheets of transition metal sulfides, two-dimensional nanosheets of clay other than hydrotalcite, and two-dimensional nanosheets of elemental phosphorus. The mass of the modifier is 5%-100% of the mass of the two-dimensional nanosheets, and the pH is adjusted to 9-12.

5. The method for preparing the dehydration and drag-reducing ion exchange membrane according to claim 1, characterized in that: The precursor is a monomer, and the preparation method includes introducing the modifier into a membrane material prepared from the monomer, wherein the mass of the modifier is 1%-100% of the mass of the monomer.

6. The method for preparing the dehydration and drag-reducing ion exchange membrane according to claim 5, characterized in that: The monomer is at least one of MOF monomer, COF monomer, hydrogel monomer, polyionic liquid monomer, and polyterephthalamide nanofiber.

7. The method for preparing the dehydration and drag-reducing ion exchange membrane according to claim 5, characterized in that: Before or after the introduction of the modifier, the method further includes a step of immersing the membrane material in an alkaline solution.

8. A dehydration and drag-reducing ion exchange membrane, characterized in that: The membrane is prepared by any one of claims 1 to 7; wherein when the precursor is a two-dimensional nanosheet, the thickness of the dehydration and drag reduction type ion exchange membrane is 1-10 μm; and when the precursor is a monomer, the thickness of the dehydration and drag reduction type ion exchange membrane is 1-50 μm.

9. A permeation energy-generating membrane, characterized in that: It includes the dehydration and drag reduction type ion exchange membrane as described in claim 8, or is made from the dehydration and drag reduction type ion exchange membrane as described in claim 8.

10. The application of the permeation energy power generation membrane according to claim 9 in permeation energy harvesting in river-sea systems.

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