Chiral MXene solution as well as preparation method and application thereof
By combining MXene with chiral ligands, the problems of poor conductivity and low stability of MXene materials in chiral functionalization research are solved, and the controllable chiral characteristics are achieved, which improves its application in chiral catalysis, optical sensing, biomedicine and quantum devices.
Patent Information
- Application Number
- CN202510722811.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-30
- Publication Date
- 2025-08-01
AI Technical Summary
In the research on chiral functionalization, existing MXene materials have problems such as poor conductivity, low stability or complex preparation, and stable chiral functionalization cannot be achieved.
By combining different types of MXene with chiral ligands such as L/D-cysteine, L/D-tartaric acid, L/D-malic acid and L/D-penicillamine, the ligand active groups are used to direct bond with MXene, and the reaction conditions and post-treatment process are precisely controlled, so as to impart MXene's controllable chiral characteristics.
It significantly improves the stability and functional applicability of MXene, realizes adjustable chiral characteristics, and is suitable for chiral catalysis, optical sensing, biomedicine and quantum devices.
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Figure CN120398060A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of two-dimensional nanomaterial functionalization, and relates to a chiral MXene solution, a preparation method thereof and an application thereof. Background Art
[0002] Chiral ligands are chemical substances with chiral centers, which can form coordination complexes with metal ions or other molecules to exhibit non-mirror symmetry. Their molecular structures usually contain chiral centers with rotational properties. The development of photoactive chiral ligands has driven the development of materials with special optical properties, such as chiral optical fibers, optical switches and optical modulators, etc. These materials have extensive applications in high-end communication technologies and biomedical fields.
[0003] Since MXene materials (MXene is a class of two-dimensional inorganic compounds in materials science. These materials are composed of transition metal carbides, nitrides or carbonitrides with a thickness of several atomic layers. It was first reported in 2011. Due to the presence of hydroxyl groups or terminal oxygen on the surface of MXene materials, they have the metallic conductivity of transition metal carbides), they have become a research hotspot in the fields of energy storage, electromagnetic shielding, etc. since their discovery in 2011 due to their high conductivity, excellent mechanical properties and tunable surface chemistry. However, the existing functionalization research of MXene mainly focuses on enhancing conductivity (such as carbon nanotube composites) or regulating surface hydrophilicity and hydrophobicity, and the development of chiral functions is almost blank.
[0004] Traditional chiral materials such as chiral metal-organic frameworks and chiral carbon nanotubes have problems such as poor conductivity, low stability or complex preparation. The high conductivity and modifiability of MXene make it have the potential to become an ideal chiral carrier, but the existing technology cannot achieve the stable chiral functionalization of MXene. Summary of the Invention
[0005] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a chiral MXene solution, a preparation method thereof and an application thereof. The present invention provides a general method for combining different types of MXene (such as Ti3C2, TiVC, VNbC, V2C and Ti3CN, etc.) with chiral ligands (such as L / D-cysteine, L / D-tartaric acid, L / D-malic acid and L / D-penicillamine) through chemical modification means. Through the directional bonding of ligand active groups (-SH, -COOH, -NH2) with MXene, this method endows MXene with adjustable chiral characteristics by precisely controlling the ligand type, reaction conditions and post-treatment process, and significantly improves its stability and functional applicability.
[0006] To achieve the purpose of this invention, the following technical solutions are adopted by the present invention:
[0007] In a first aspect, the present invention provides a chiral MXene solution, and the raw materials for preparing the chiral MXene solution include MXene, a chiral ligand, and a solvent;
[0008] The chiral ligand includes any one or a combination of at least two of L / D-cysteine, L / D-tartaric acid, L / D-malic acid, and L / D-penicillamine.
[0009] In the present invention, the chiral MXene solution prepared by combining a specific type of chiral ligand with MXene has adjustable chiral properties and exhibits excellent visible light absorption and circular dichroism (CD) effects.
[0010] Preferably, the MXene includes any one or a combination of at least two of Ti3C2, TiVC, VNbC, V2C, and Ti3CN.
[0011] Preferably, the mass ratio of the MXene to the chiral ligand is (0.005:1 - 0.035):1, such as 0.005:1, 0.01:1, 0.015:1, 0.02:1, 0.025:1, 0.03:1, 0.035:1, etc.
[0012] Preferably, the solvent includes water and / or an organic solvent.
[0013] Preferably, the organic solvent includes any one or a combination of at least two of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), ethanol, acetone, methanol, and propylene glycol methyl ether acetate (PGMEA).
[0014] Preferably, the chiral MXene solution includes an aqueous chiral MXene solution or an organic solvent solution of chiral MXene.
[0015] Preferably, the MXene is prepared by the following method:
[0016] (1) Mix deionized water and concentrated hydrochloric acid, then add an HF aqueous solution and MAX, and react under stirring conditions to obtain a reaction solution;
[0017] (2) Centrifuge the reaction solution obtained in step (1), pour off the supernatant, add deionized water, continue to wash and centrifuge again until neutral, then add LiCl and H2O, stir, then perform a third centrifugation, retain the precipitate, add water, perform a fourth centrifugation, retain the precipitate, add water, fractionate, and take the supernatant to obtain an aqueous MXene solution.
[0018] That is, the above method obtains a single-layer MXene aqueous solution through HF etching. It should be noted that the preparation method of MXene in the present invention is not limited to the above one, and can also be prepared by other preparation methods.
[0019] Preferably, the MAX in step (1) is a precursor of MXene.
[0020] Preferably, when the dosage of MAX in step (1) is 1 g, the dosage of deionized water is 5 - 10 mL, such as 5 mL, 6 mL, 7 mL, 8 mL, 9 mL, 10 mL, etc.
[0021] Preferably, when the dosage of MAX in step (1) is 1 g, the dosage of concentrated hydrochloric acid is 10 - 15 mL, such as 10 mL, 11 mL, 12 mL, 13 mL, 14 mL, 15 mL, etc.
[0022] Preferably, when the dosage of MAX in step (1) is 1 g, the dosage of HF aqueous solution is 1 - 5 mL, such as 1 mL, 2 mL, 3 mL, 4 mL, 5 mL, etc.
[0023] Preferably, the mass concentration of the HF aqueous solution is 30% - 50%, such as 30%, 35%, 40%, 45%, 50%, etc.
[0024] Preferably, the temperature of the reaction in step (1) is 35 - 40 °C, such as 35 °C, 36 °C, 38 °C, 40 °C, etc., and the reaction time is 22 - 24 h, such as 22 h, 23 h, 24 h, etc.
[0025] Preferably, the rotation speed of the centrifugation in step (2) is 5000 - 5500 r / min, such as 5000 r / min, 5100 r / min, 5200 r / min, 5300 r / min, 5400 r / min, 5500 r / min, etc., and the centrifugation time is 2 - 3 min, such as 2 min, 2.5 min, 3 min, etc.
[0026] Preferably, the rotation speed of the re - centrifugation in step (2) is 5000 - 5500 r / min, such as 5000 r / min, 5100 r / min, 5200 r / min, 5300 r / min, 5400 r / min, 5500 r / min, etc., and the re - centrifugation time is 2 - 3 min, such as 2 min, 2.5 min, 3 min, etc.
[0027] Preferably, the number of times of re - centrifugation in step (2) is 4 - 5 times.
[0028] Preferably, the temperature of the stirring in step (2) is 35 - 40°C, such as 35°C, 36°C, 38°C, 40°C, etc., and the time of the stirring is 2 - 3 h, such as 2 h, 2.5 h, 3 h, etc.
[0029] Preferably, the rotation speed of the third centrifugation in step (2) is 5000 - 5500 r / min, such as 5000 r / min, 5100 r / min, 5200 r / min, 5300 r / min, 5400 r / min, 5500 r / min, etc., and the time of the third centrifugation is 2 - 3 min, such as 2 min, 2.5 min, 3 min, etc.
[0030] Preferably, the rotation speed of the fourth centrifugation in step (2) is 8000 - 8500 r / min, such as 8000 r / min, 8100 r / min, 8200 r / min, 8300 r / min, 8400 r / min, 8500 r / min, etc., and the time of the fourth centrifugation is 3 - 4 min, such as 3 min, 3.5 min, 4 min, etc.
[0031] Preferably, the rotation speed of the classification in step (2) is 3000 - 3500 r / min, such as 3000 r / min, 3100 r / min, 3200 r / min, 3300 r / min, 3400 r / min, 3500 r / min, etc., and the time of the classification is 1 - 2 min, such as 1 min, 1.5 min, 2 min, etc.
[0032] In a second aspect, the present invention provides a method for preparing a chiral MXene solution as described in the first aspect, and the preparation method includes the following steps:
[0033] (A) Dilute the MXene aqueous solution with water to obtain a diluted MXene aqueous solution;
[0034] (B) Mix the chiral ligand with water to obtain a chiral ligand aqueous solution;
[0035] (C) Mix the diluted MXene aqueous solution with the chiral ligand aqueous solution to obtain a chiral MXene aqueous solution;
[0036] Alternatively, the preparation method includes the following steps:
[0037] (a) Dilute the MXene aqueous solution with water to obtain a diluted MXene aqueous solution, centrifuge it, take out the upper clear liquid, and add an organic solvent to the lower precipitate to obtain an MXene organic solvent solution;
[0038] (b) Mix the chiral ligand with the organic solvent to obtain a chiral ligand organic solvent solution;
[0039] (c) Mixing the organic solvent solution of MXene with the organic solvent solution of the chiral ligand to obtain a chiral MXene organic solvent solution.
[0040] The chiral ligand in step (B) and step (b) includes any one of L / D-cysteine, L / D-tartaric acid, L / D-malic acid, and L / D-penicillamine, or a combination of at least two thereof.
[0041] The chiral ligand tartaric acid is a dicarboxylic acid widely distributed in nature, found in plants such as grapes and bananas, as well as in wine. Due to its unique chiral properties and diverse chemical functions, it has broad potential applications in chemistry and materials science. Tartaric acid was first isolated from tartar, a byproduct of winemaking. In 1848, Louis Pasteur observed the crystalline form of tartaric acid salts through a microscope and discovered the phenomenon of molecular chirality, laying the foundation for stereochemistry. Pasteur exploited the difference in optical activity of ammonium tartrate to separate left-tartaric acid (L-(+)-) and right-tartaric acid (D-(-)-), pioneering chiral resolution technology. Tartaric acid has the molecular formula HOOC-CH(OH)-CH(OH)-COOH, containing two carboxyl groups and two hydroxyl groups. These functional groups give tartaric acid its unique chemical properties, and the presence of chiral carbon atoms determines the optical activity of tartaric acid, which influences its chemical reaction behavior.
[0042] Malic acid, with the molecular formula C4H6O5, is an organic acid containing a chiral carbon atom. It has two enantiomers, D-malic acid and L-malic acid. L-malic acid is the most common form found in nature and is found in large quantities in fruits such as apples. Malic acid has two carboxyl groups and one hydroxyl group, making it an important four-carbon chiral organic compound. Due to its natural chirality, coordination ability, and structural diversity, malic acid plays multiple roles in the field of chiral optics, serving as a resolution tool, catalytic ligand, and material building block. Its core role is to achieve efficient enantiomer separation, asymmetric synthesis, and the creation of chiral functional materials through chiral induction, recognition, and transmission, thereby promoting the development of chiral control technologies in pharmaceuticals, materials, and analytical sciences.
[0043] The chemical formula of penicillamine is C5H 11NO2S, a sulfur-containing amino acid derivative, has two chiral enantiomers, L-type and D-type, and its English name is Penicillamine. The asymmetry of carbon atoms in the molecule endows penicillamine with chirality. This chiral complex enables the reactants to follow a specific stereochemical trajectory in asymmetric catalytic reactions, thereby producing chiral products with high optical purity. The thiol group of penicillamine can adsorb on the surface of metal nanoparticles, and its chiral configuration induces the nanoparticles to form a chiral arrangement, generating chiral optical activity. During the self-assembly process, the chiral center of penicillamine can guide the molecules to form a helical structure or a chiral superlattice, endowing the material with unique optical properties.
[0044] The present invention provides a preparation method of chiral MXene with strong universality and simple process. The ligand active groups (-SH, -COOH, -NH2) are directionally bonded to MXene, and it is suitable for various MXenes such as Ti and V. By precisely controlling the ligand type, reaction conditions and post-treatment process, this method endows MXene with adjustable chiral properties, and significantly improves its stability and functional applicability, and can be widely used in the fields of chiral catalysis, optical sensing, biomedicine and quantum devices. At the same time, the present invention also studies the chirality of the DMF solution, methanol solution or PGMEA solution of MXene modified by chiral ligands (such as L / D-cysteine, L / D-tartaric acid, L / D-malic acid and L / D-penicillamine).
[0045] Preferably, the concentration of the diluted aqueous solution of MXene in step (A) is 0.5 - 2 mg / mL, such as 0.5 mg / mL, 1 mg / mL, 1.5 mg / mL, 2 mg / mL, etc.
[0046] Preferably, the concentration of the aqueous solution of the chiral ligand in step (B) is 0.001 - 0.002 g / mL, such as 0.001 g / mL, 0.0012 g / mL, 0.0014 g / mL, 0.0015 g / mL, 0.0016 g / mL, 0.0018 g / mL, 0.002 g / mL, etc.
[0047] Preferably, the dosage ratio of the diluted aqueous solution of MXene to the aqueous solution of the chiral ligand in step (C) is 40 - 60 μL:1 - 3 mL. 40 - 60 μL can be, for example, 40 μL, 45 μL, 50 μL, 55 μL, 60 μL, etc., and 1 - 3 mL can be, for example, 1 mL, 1.5 mL, 2 mL, 2.5 mL, 3 mL, etc.
[0048] Preferably, the concentration of the organic solvent solution of MXene in step (a) is 0.5 - 2 mg / mL, such as 0.5 mg / mL, 1 mg / mL, 1.5 mg / mL, 2 mg / mL, etc.
[0049] Preferably, the concentration of the organic solvent solution of the chiral ligand in step (b) is 0.001 - 0.002 g / mL, such as 0.001 g / mL, 0.0012 g / mL, 0.0014 g / mL, 0.0015 g / mL, 0.0016 g / mL, 0.0018 g / mL, 0.002 g / mL, etc.
[0050] Preferably, the dosage ratio of the organic solvent solution of MXene to the organic solvent solution of the chiral ligand in step (c) is 40 - 60 μL:1 - 3 mL. 40 - 60 μL can be, for example, 40 μL, 45 μL, 50 μL, 55 μL, 60 μL, etc., and 1 - 3 mL can be, for example, 1 mL, 1.5 mL, 2 mL, 2.5 mL, 3 mL, etc.
[0051] Preferably, the organic solvents in step (a) and step (b) independently include any one or a combination of at least two of N,N - dimethylformamide (DMF), N,N - dimethylacetamide (DMA), ethanol, acetone, methanol, and propylene glycol methyl ether acetate (PGMEA).
[0052] Preferably, the organic solvents in step (a) and step (b) are the same.
[0053] In the third aspect, the present invention provides an application of the chiral MXene solution as described in the first aspect in chiral catalysis, optical sensing, biomedicine, and quantum devices.
[0054] Natural MXene does not have chiral optical activity. By chemically modifying chiral ligands (such as L / D - cysteine, L / D - tartaric acid, L / D - malic acid, and L / D - penicillamine) onto the surfaces of different types of MXene (Ti3C2, TiVC, VNbC, V2C, and Ti3CN), unique chiral optical properties, selective recognition ability, and interfacial enhancement effects are imparted to the materials.
[0055] In terms of circularly polarized light (CPL) detectors, cutting - edge technologies such as quantum computing have put forward high - sensitivity and high - stability requirements for CPL detection materials. Traditional materials such as organic semiconductor materials have deficiencies in terms of stability and are difficult to meet the actual application requirements. Chiral MXene can be integrated with ITO electrodes as the active layer. The added value of chiral materials is that the device can sense and distinguish the circular polarization of incident light. Chiral MXene materials provide an opportunity for the direct detection of CPL.
[0056] In chiral biosensing, chiral MXene can detect target molecules through changes in CD signals. The chiral interface can enhance molecular - specific recognition, providing the possibility for a new type of biosensing method. <X
[0057] In the field of asymmetric synthesis, the synthesis of chiral drugs highly relies on highly enantioselective catalysts. Traditional homogeneous catalysts have problems such as high cost and difficulty in recycling. Chiral MXene can adjust the microenvironment of active sites by regulating the ratio of ligands.
[0058] In the fields of quantum technology and advanced manufacturing, spin-polarized transport materials possess strong spin-orbit coupling. Traditional metals have high resistivity, while chiral MXene has good conductivity and low resistivity, is compatible with complementary metal-oxide semiconductor (CMOS) processes, and can be used in magnetoresistive random access memory (MRAM) storage units.
[0059] Compared with the prior art, the present invention has the following beneficial effects:
[0060] The present invention provides a preparation method of chiral MXene with strong universality and simple process, realizing the efficient bonding of different types of MXene (such as Ti3C2, TiVC, VNbC, V2C, and Ti3CN) with various chiral ligands (L / D-cysteine, L / D-tartaric acid, L / D-malic acid, and L / D-penicillamine), and enhancing the loading stability of chiral ligands through chemical bonding such as coordination bonds and covalent bonds, thereby enabling precise regulation of the optical activity of the material such as CD signal intensity and enantioselectivity. By precisely controlling the ligand type, reaction conditions, and post-treatment process, this method endows MXene with adjustable chiral properties, significantly improves its stability and functional applicability, and can be widely applied in the fields of chiral catalysis, optical sensing, biomedicine, and quantum devices. At the same time, the present invention also studies the chirality of MXene modified by chiral ligands (such as L / D-cysteine, L / D-tartaric acid, L / D-malic acid, and L / D-penicillamine) in DMF solution, methanol solution, or PGMEA solution. BRIEF DESCRIPTION OF THE DRAWINGS
[0061] Figure 1 A photograph of the Ti3C2 aqueous solution obtained in step (1) of Example 1.
[0062] Figure 2 A CD diagram of the chiral MXene aqueous solution provided in Example 1.
[0063] Figure 3 An absorption spectrum diagram of the chiral MXene aqueous solution provided in Example 1.
[0064] Figure 4 ] A CD diagram of the chiral MXene aqueous solution provided in Example 2.
[0065] Figure 5 An absorption spectrum diagram of the chiral MXene aqueous solution provided in Example 2.
[0066] Figure 6Photograph of the TiVC aqueous solution obtained in step (1) of Example 3.
[0067] Figure 7 CD diagram of the chiral MXene aqueous solution provided in Example 3.
[0068] Figure 8 Absorption spectrum diagram of the chiral MXene aqueous solution provided in Example 3.
[0069] Figure 9 CD diagram of the chiral MXene aqueous solution provided in Example 4.
[0070] Figure 10 Absorption spectrum diagram of the chiral MXene aqueous solution provided in Example 4.
[0071] Figure 11 CD diagram of the chiral MXene DMF solution provided in Example 5.
[0072] Figure 12 CD diagram of the chiral MXene DMF solution provided in Example 6. Detailed implementation manners
[0073] The technical solution of the present invention will be further described below through specific implementation manners. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations on the present invention.
[0074] Preparation Example 1
[0075] In this preparation example, an MXene aqueous solution is provided, specifically a Ti3C2 aqueous solution. The preparation method includes the following steps:
[0076] First step, etching. The specific operation is as follows: Use a pipette to take 6 mL of deionized water into a plastic bottle (turn on the magnetic stirrer and start stirring), then add 12 mL of concentrated hydrochloric acid and 2.5 mL of HF aqueous solution (mass concentration of 40%), and then add 1 g of MAX (Ti3AlC2) in multiple small amounts. Set the oil bath temperature of the magnetic stirrer to 35°C and stir for 24 h.
[0077] Second step, removing acid and exfoliating MXene. The specific operation is as follows: Take out the plastic bottle, wipe the oil on the surface, pour the reaction solution into a centrifuge tube, centrifuge at 5000 r / min for 3 minutes, pour the supernatant into the HF recovery bucket, add deionized water, continue to wash, and centrifuge at 5000 r / min for 3 minutes (4 times in total) until neutral. Then add 1 g of LiCl and 60 mL of H2O (in which the MXene precipitate dissolves), set the magnetic stirrer, and stir at an oil bath of 35°C for 2 h.
[0078] Finally, the configuration operation of MXene (the final product is MXene nanosheets with smaller sizes): Take a plastic bottle, wipe off the oil, put it into a centrifuge tube, centrifuge at 5000 r / min for 3 min, keep the precipitate, add water, continue to centrifuge and wash once, centrifuge at 8000 r / min for 4 min, keep the precipitate, add water to disperse the precipitate evenly, centrifuge at 3500 r / min for 2 min for classification, take the supernatant to obtain a monolayer MXene aqueous solution.
[0079] Preparation Example 2
[0080] In this preparation example, an MXene aqueous solution is provided, specifically a TiVC aqueous solution, and the preparation method includes the following steps:
[0081] First, place the PP bottle in an oil bath, rotate at 750 rpm, stir at room temperature, then add 2.8 g of LiF to the PP bottle, use a pipette to add 30 mL of HC1, stir for 30 min to in-situ generate HF. Raise the temperature of the stirring table to 40 °C, slowly add 2 g of MAX (TiVAlC), and stir for 24 h to etch the MAX. Pour the etched solution into a centrifuge tube, centrifuge at 3500 rpm each time for 5 min, centrifuge 8 times to wash the solution to neutral. Continue to increase the centrifugation speed to 8000 rpm and centrifuge for 3 min to further expand the TiVC MXene. Add pure water to the expanded MXene, shake it by hand until it is evenly dispersed, then continue to centrifuge, adjust the speed to 3500 rpm, and centrifuge for 2 min to separate out the monolayer MXene aqueous solution.
[0082] Example 1
[0083] In this example, a chiral MXene aqueous solution is provided, and the preparation method includes the following steps:
[0084] (1) Take 1 mL of the Ti3C2 aqueous solution provided in Preparation Example 1, add distilled water for dilution to obtain a Ti3C2 aqueous solution with a concentration of 1 mg / mL;
[0085] (2) Weigh 0.015 g of D-tartaric acid (D-TA) and L-tartaric acid (L-TA) respectively, add 10 mL of water for dissolution respectively, and shake on an oscillator for 15 min to ensure complete dissolution to obtain an aqueous solution of D-tartaric acid and an aqueous solution of L-tartaric acid;
[0086] (3) Take two 50 μL of the Ti3C2 aqueous solution with a concentration of 1 mg / mL, mix them with 2 mL of the aqueous solution of D-tartaric acid and 2 mL of the aqueous solution of L-tartaric acid obtained in step (2) respectively, and shake well to obtain a chiral MXene aqueous solution.
[0087] The photo of the Ti3C2 aqueous solution obtained in step (1) of this example is asFigure 1 As shown, it can be seen that the Ti3C2 aqueous solution is evenly dispersed.
[0088] The CD diagram and absorption spectrum diagram of the chiral MXene aqueous solution provided in this example are respectively as Figure 2 and Figure 3 shown. It can be seen that the chiral MXene aqueous solution has good chiral properties.
[0089] Example 2
[0090] The difference between this example and Example 1 is only that 0.0134 g of D-malic acid (D-MA) and 0.0134 g of L-malic acid (L-MA) are respectively used to replace D-tartaric acid (D-TA) and L-tartaric acid (L-TA) in step (2).
[0091] The CD diagram and absorption spectrum diagram of the chiral MXene aqueous solution provided in this example are respectively as Figure 4 and Figure 5 shown. It can be seen that the chiral MXene aqueous solution has good chiral properties.
[0092] Example 3
[0093] A chiral MXene aqueous solution is provided in this example, and the preparation method includes the following steps:
[0094] (1) Take 1 mL of the TiVC aqueous solution provided in Preparation Example 2, add distilled water for dilution to obtain a TiVC aqueous solution with a concentration of 1 mg / mL;
[0095] (2) Weigh 0.015 g of D-tartaric acid (D-TA) and L-tartaric acid (L-TA) respectively, add 10 mL of water for dissolution, and shake on an oscillator for 15 min to ensure complete dissolution to obtain an aqueous solution of D-tartaric acid and an aqueous solution of L-tartaric acid;
[0096] (3) Take two 50 μL of the TiVC aqueous solution with a concentration of 1 mg / mL, and mix them with 2 mL of the aqueous solution of D-tartaric acid and 2 mL of the aqueous solution of L-tartaric acid obtained in step (2) respectively, and shake well to obtain a chiral MXene aqueous solution.
[0097] The photo of the TiVC aqueous solution obtained in step (1) of this example is as Figure 6 shown. It can be seen that the TiVC aqueous solution is evenly dispersed.
[0098] The CD diagram and absorption spectrum diagram of the chiral MXene aqueous solution provided in this example are respectively as Figure 7 and Figure 8 shown. It can be seen that the chiral MXene aqueous solution has good chiral properties.
[0099] Example 4
[0100] The difference between this example and Example 3 is only that in step (2), D-tartaric acid (D-TA) and L-tartaric acid (L-TA) are respectively replaced by 0.0134 g of D-malic acid (D-MA) and 0.0134 g of L-malic acid (L-MA).
[0101] The CD diagram and absorption spectrum diagram of the chiral MXene aqueous solution provided in this example are respectively as Figure 9 and Figure 10 shown, and it can be seen that the chiral MXene aqueous solution has good chiral properties.
[0102] Example 5
[0103] In this example, a chiral MXene DMF solution is provided, and the preparation method includes the following steps:
[0104] (1) Take 1 mL of the Ti3C2 aqueous solution provided in Preparation Example 1, add distilled water for dilution to obtain a Ti3C2 aqueous solution with a concentration of 1 mg / mL, centrifuge at 8000 rpm for 10 min. After taking out the upper clear liquid, add DMF to the lower precipitate and shake it thoroughly to dissolve, to obtain a Ti3C2 DMF solution with a concentration of 1 mg / mL;
[0105] (2) Weigh 0.015 g of D-tartaric acid (D-TA) and L-tartaric acid (L-TA) respectively, add 10 mL of DMF for dissolution respectively, and shake on an oscillator for 15 min to ensure complete dissolution, to obtain a DMF solution of D-tartaric acid and a DMF solution of L-tartaric acid;
[0106] (3) Take two 50 μL of the Ti3C2 DMF solution with a concentration of 1 mg / mL, and mix them with 2 mL of the DMF solution of D-tartaric acid and 2 mL of the DMF solution of L-tartaric acid obtained in step (2) respectively, and shake well to obtain a chiral MXene DMF solution.
[0107] The CD diagram of the chiral MXene DMF solution provided in this example is as Figure 11 shown, and it can be seen that the chiral MXene DMF solution has good chiral properties.
[0108] Example 6
[0109] The difference between this example and Example 5 is only that step (1) is different, specifically as follows:
[0110] Take 1 mL of the TiVC aqueous solution provided in Preparation Example 2, add distilled water for dilution to obtain a TiVC aqueous solution with a concentration of 1 mg / mL, centrifuge at 8000 rpm for 10 min. After taking out the supernatant, add DMF to the lower precipitate and shake it thoroughly to dissolve, obtaining a DMF solution of TiVC with a concentration of 1 mg / mL.
[0111] The CD diagram of the chiral MXene DMF solution provided in this example is as Figure 12 shown, and it can be seen that this chiral MXene DMF solution has good chiral properties.
[0112] In summary, the chiral MXene solutions provided by the present invention all have good chiral properties.
[0113] The applicant declares that the present invention uses the above embodiments to illustrate the chiral MXene solution, its preparation method and application of the present invention, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent replacement of the raw materials selected for the present invention, the addition of auxiliary components, the selection of specific methods, etc. all fall within the protection scope and the disclosure scope of the present invention.
Claims
1. A chiral MXene solution, characterized in that, The raw materials for preparing the chiral MXene solution include MXene, chiral ligand, and solvent; The chiral ligand includes any one or a combination of at least two of L / D-cysteine, L / D-tartaric acid, L / D-malic acid, and L / D-penicillamine.
2. The chiral MXene solution according to claim 1, characterized in that, The MXene includes any one or a combination of at least two of Ti3C2, TiVC, VNbC, V2C, and Ti3CN; Preferably, the mass ratio of the MXene to the chiral ligand is (0.005 - 0.035):1; Preferably, the solvent includes water and / or organic solvent; Preferably, the organic solvent includes any one or a combination of at least two of N,N-dimethylformamide, N,N-dimethylacetamide, ethanol, acetone, methanol, and propylene glycol methyl ether acetate; Preferably, the chiral MXene solution includes an aqueous chiral MXene solution or an organic solvent solution of chiral MXene.
3. The chiral MXene solution according to claim 1 or 2, characterized in that, The MXene is prepared by the following method: (1) Mix deionized water and concentrated hydrochloric acid, then add an HF aqueous solution and MAX, and react under stirring conditions to obtain a reaction solution; (2) Centrifuge the reaction solution obtained in step (1), pour off the supernatant, add deionized water, continue to wash and centrifuge again until neutral, then add LiCl and H2O, stir, and then perform a third centrifugation, retain the precipitate, add water, perform a fourth centrifugation, retain the precipitate, add water, fractionate, and take the supernatant to obtain an aqueous MXene solution.
4. The chiral MXene solution according to claim 3, wherein The MAX in step (1) is the precursor of MXene; Preferably, based on 1 g of the amount of MAX in step (1), the amount of deionized water used is 5 - 10 mL; Preferably, based on 1 g of the amount of MAX in step (1), the amount of concentrated hydrochloric acid used is 10 - 15 mL; Preferably, based on 1 g of the amount of MAX in step (1), the amount of the HF aqueous solution used is 1 - 5 mL; Preferably, the mass concentration of the HF aqueous solution is 30% - 50%; Preferably, the temperature of the reaction in step (1) is 35 - 40 °C, and the reaction time is 22 - 24 h.
5. The chiral MXene solution according to claim 3 or 4, characterized in that, The rotation speed of the centrifugation in step (2) is 5000 - 5500 r / min, and the centrifugation time is 2 - 3 min; Preferably, the rotation speed of the re-centrifugation in step (2) is 5000 - 5500 r / min, and the re-centrifugation time is 2 - 3 min; Preferably, the number of times of re-centrifugation in step (2) is 4 - 5 times; Preferably, the temperature of the stirring in step (2) is 35 - 40 °C, and the stirring time is 2 - 3 h; Preferably, the rotation speed of the third centrifugation in step (2) is 5000 - 5500 r / min, and the third centrifugation time is 2 - 3 min; Preferably, the rotation speed of the fourth centrifugation in step (2) is 8000 - 8500 r / min, and the fourth centrifugation time is 3 - 4 min; Preferably, the rotation speed of the fractionation in step (2) is 3000 - 3500 r / min, and the fractionation time is 1 - 2 min.
6. A method for preparing a chiral MXene solution according to any one of claims 1-5, characterized in that, The preparation method includes the following steps: (A) Dilute the MXene aqueous solution with water to obtain a diluted MXene aqueous solution; (B) Mix the chiral ligand with water to obtain a chiral ligand aqueous solution; (C) Mix the diluted MXene aqueous solution with the chiral ligand aqueous solution to obtain a chiral MXene aqueous solution; Alternatively, the preparation method includes the following steps: (a) Dilute the MXene aqueous solution with water to obtain a diluted MXene aqueous solution, centrifuge it, after taking out the supernatant, add an organic solvent to the lower precipitate to obtain an MXene organic solvent solution; (b) Mix the chiral ligand with the organic solvent to obtain a chiral ligand organic solvent solution; (c) Mix the MXene organic solvent solution with the chiral ligand organic solvent solution to obtain a chiral MXene organic solvent solution.
7. The preparation method according to claim 6, characterized in that, The concentration of the diluted MXene aqueous solution in step (A) is 0.5 - 2 mg / mL; Preferably, the concentration of the chiral ligand aqueous solution in step (B) is 0.001 - 0.002 g / mL; Preferably, the dosage ratio of the diluted MXene aqueous solution to the chiral ligand aqueous solution in step (C) is 40 - 60 μL: 1 - 3 mL.
8. The preparation method according to claim 6 or 7, characterized in that, The concentration of the MXene organic solvent solution in step (a) is 0.5 - 2 mg / mL; Preferably, the concentration of the chiral ligand organic solvent solution in step (b) is 0.001 - 0.002 g / mL; Preferably, the dosage ratio of the MXene organic solvent solution to the chiral ligand organic solvent solution in step (c) is 40 - 60 μL: 1 - 3 mL.
9. The preparation method according to any one of claims 6-8, characterized in that, The organic solvents in step (a) and step (b) each independently include any one or a combination of at least two of N,N-dimethylformamide, N,N-dimethylacetamide, ethanol, acetone, methanol, and propylene glycol methyl ether acetate; Preferably, the organic solvents in step (a) and step (b) are the same.
10. Application of a chiral MXene solution as described in any one of claims 1 - 5 in chiral catalysis, optical sensing, biomedicine, and quantum devices.