Molecular ferroelectric catalytic material and method for catalytically synthesizing amino acid by using same

Abstract

The invention relates to an amino acid preparation technology, in particular to a molecular ferroelectric catalytic material and a method for catalytically synthesizing amino acid by using the material. The amino acid synthesis method comprises the following steps: adding a molecular ferroelectric catalytic material into a reaction container, adding a small amount of deionized water, and enabling the molecular ferroelectric catalytic material in the reaction container to be partially dissolved to be in an excessive state; introducing a mixed gas of CO2 and N2 into the bottom of the reaction container; the reaction system is treated in a mechanical vibration mode, and after the reaction is completed, the reaction mixture is filtered to obtain the amino acid. According to the method, all twenty protein amino acids are synthesized from water and CO2 and N2 mixed gas under mechanical vibration through ferroelectric catalysis for the first time, and the molecular ferroelectric catalyst has good stability and recoverability. Compared with a traditional amino acid synthesis method, the method is simple, efficient and environment-friendly, the reaction condition is mild, complex reagents and high-temperature and high-pressure conditions are not needed, and the green chemical requirement is met.

Description

Technical Field

[0001] The present invention relates to a method for synthesizing amino acids, and particularly to a method for converting neutral gases (CO2 and N2) and water into protein amino acids by mechanical energy drive at normal temperature and pressure by utilizing the piezoelectricity and ferroelectricity of molecular ferroelectric crystals (such as cyclic molecular ferroelectrics β -cyclodextrin hydrate, crown ether derivatives, etc.). Background Art

[0002] Ferroelectrics are an important class of multifunctional electroactive materials with reversible spontaneous polarization, and are widely used in fields such as data storage, energy conversion, and mechanical drive. Recently, ferroelectrics have attracted increasing attention as emerging catalysts, in which the polarization-induced built-in electric field and the polarization change under external stimuli such as mechanical stress promote the separation and migration of carriers.

[0003] Based on classical ferroelectrics such as inorganic BaTiO3, their catalytic potential in water splitting for hydrogen production, organic synthesis, and environmental remediation has been deeply studied. As a beneficial supplement to commercial inorganic ferroelectrics, molecular ferroelectrics have received great attention in recent years due to their advantages such as easy processing, light weight, and mechanical flexibility. It is worth noting that molecular ferroelectrics have the advantage of low acoustic impedance, which helps the transfer of mechanical energy from the solvent to the catalyst. Inorganic ferroelectrics are insoluble in conventional solvents, while molecular ferroelectrics have good solubility in conventional solvents and can be regenerated and recycled by dissolution and recrystallization. In addition, molecular ferroelectrics can have an intrinsic chirality that cannot be achieved by inorganic ferroelectrics, which makes them highly promising in the catalytic synthesis of chiral compounds such as protein amino acids. Protein amino acids are the basic components of life and have wide applications in fields such as biotechnology, pharmaceuticals, and the food industry. Although many strategies for non-biological synthesis of amino acids have been developed since 1850, due to their unique chemical structure, it is still a major challenge to obtain all twenty protein amino acids by simple methods.

[0004] Since Strecker first synthesized amino acids in 1850 ( Justus Liebigs Ann. Chem. 1850, 75 , 27-45), various strategies such as electrochemical reduction, photocatalysis, and pyrolysis have been developed for the synthesis of amino acids. However, the existing methods generally have the following problems: the dependence of amino acid synthesis on raw materials, traditional methods rely on petroleum-based reagents such as cyanides and aldehydes, which pose toxicity and environmental risks; product limitations, even using the Miller-Urey experiment ( Science 1953, 117,528 - 529), can only generate 3 - 10 kinds of amino acids, and requires a strongly reducing atmosphere including CH4 and NH3, which does not conform to the early Earth's neutral atmospheric environment; there is a lack of stereoselectivity, and the enantioselectivity of L - type amino acids in abiotic synthesis is extremely low (close to the racemate), unable to meet the needs of origin - of - life research and chiral drug synthesis. Although there have been recent studies attempting to use CO2 and N2 as raw materials, the product types are limited (<10 kinds), and high temperature / high pressure or noble metal catalysts are required, making large - scale application difficult.

[0005] Existing methods for synthesizing amino acids face multiple bottlenecks. First, traditional synthesis methods rely on toxic reagents (such as cyanides) and petroleum - based raw materials, posing safety hazards and environmental pollution problems. Second, the product types of existing technologies are limited and cannot cover all 20 kinds of amino acids. Moreover, the synthetic reaction paths of different amino acids are complex and difficult to achieve uniformly. In addition, existing methods have a racemate problem, lacking an effective chiral induction mechanism, which increases the separation cost. The reaction conditions are harsh, requiring high temperature, high pressure, or strong electric fields, with high energy consumption and complex equipment. There are limitations in catalytic materials, such as expensive noble metal catalysts and chiral catalysts.

[0006] Traditional technologies are difficult to meet the requirements of green synthesis, full - species coverage, stereoselectivity, and mild reaction conditions. Therefore, in view of these problems, the present invention proposes a cavity - polarization cooperative catalysis mechanism through molecular ferroelectric crystals (such as cyclic molecular ferroelectrics β - cyclodextrin hydrate, crown ether derivatives, etc.), providing a breakthrough new technical path and a new solution for amino acid synthesis. Summary of the Invention

[0007] The present invention aims at the deficiencies of the prior art and proposes a molecular ferroelectric catalytic material and a method for catalytically synthesizing amino acids using this material.

[0008] The technical solution adopted by the present invention: A method for catalytically synthesizing amino acids using a molecular ferroelectric, the synthesis reaction process including: Step S1, adding the molecular ferroelectric catalytic material into a reaction vessel, adding a small amount of deionized water to make there be a large number of undissolved molecular ferroelectric crystals in the reaction vessel; Step S2, introducing a mixed gas of CO2 and N2 to the bottom of the reaction vessel, the volume ratio of CO2 and N2 in the mixed gas being 50 - 80%:50 - 20%); Step S3, performing ultrasonic treatment on the reaction system by means of mechanical vibration such as ultrasonic waves for a treatment time of 0.8 - 1.2 hours. After the reaction is completed, filtering the reaction mixture to obtain the amino acid.

[0009] To introduce sulfur element, in step S2, while introducing a mixed gas of CO2 and N2, 3% by mass of sulfur powder can be added to the reaction solution, and ultrasonic treatment can be continuously performed to obtain sulfur-containing amino acids.

[0010] The reaction mixture is filtered and diluted, and the sample is sprayed into an ion trap mass spectrometer through electrospray ionization for detection. The results prove that the method of the present invention can synthesize more than a dozen protein amino acids.

[0011] In the method for catalytic synthesis of amino acids by the molecular ferroelectric body described above, in step S3, ultrasonic waves are used to provide mechanical stress, and the ultrasonic frequency is not lower than 40 kHz. Other mechanical vibration methods can also be used, such as reactor vibration, vibrating disk vibration, fluidized bed vibration, or vibrating screen vibration.

[0012] The technical principle of the present invention: Taking β -cyclodextrin hydrate as an example, it includes the following key points: (1) The polarization electric field drives charge separation, and the spontaneous polarization of the β -cyclodextrin hydrate crystal along the b axis ( P s =4.3 μC / cm 2 ) forms a built-in electric field, and under the action of the periodic mechanical stress generated by ultrasonic waves, a piezoelectric potential is generated through the piezoelectric effect ( d 33 ≈26 pC / N).

[0013] (2) β -cyclodextrin hydrate chiral induction. The structure of β -cyclodextrin hydrate is a cyclic cavity (with a diameter of about 6.0 Å) that can adsorb N2; it is connected by seven glucose units in a "head-to-tail" manner. β The inherent chirality of

[0014] -cyclodextrin hydrate can achieve stereoselective synthesis. β (3) Acoustic impedance matching improves energy efficiency. The acoustic impedance of

[0015] -cyclodextrin hydrate (2.39 MRayl) is much lower than that of BaTiO3 (21.05 MRayl) and is highly matched with the acoustic impedance of water (1.5 MRayl), which is beneficial to ultrasonic energy transfer.

[0016] The molecular ferroelectric crystal used in the present invention for catalytic synthesis of amino acids is a cyclic molecular ferroelectric body β -cyclodextrin hydrate or crown ether derivatives.

[0017] Advantages of the invention: 1. For the first time, the present invention utilizes the polarization electric field, piezoelectric effect and chiral cavity structure of ferroelectric molecular ferroelectric crystals (such as cyclic molecular ferroelectrics β -cyclodextrin hydrate, crown ether derivatives, etc.), and through mechanical energy (ultrasonic wave), water and neutral atmosphere (CO2 / N2) are excited to achieve the efficient synthesis of all 20 protein amino acids, and significantly improve the L-enantiomer selectivity (ee value 75.7%). The present invention realizes for the first time the synthesis of all twenty protein amino acids by ferroelectric catalysis of water and a mixed gas of CO2 and N2 under ultrasound, including two sulfur-containing amino acids (methionine and cysteine) generated after adding sulfur powder, and the L-amino acid enantiomeric excess (ee value 75.7%) is induced by the inherent chirality of the chiral molecular ferroelectric.

[0018] 2. The molecular ferroelectric catalyst has good stability, durability and recyclability. The crystal structure remains unchanged after the reaction and can be recycled. The present invention uses molecular ferroelectrics as catalysts to ferroelectrically catalyze the synthesis of twenty protein amino acids from a mixed gas of water, CO2 and N2 under ultrasonic excitation at normal temperature and pressure.

[0019] 3. Compared with the traditional amino acid synthesis method, the method of the present invention has the advantages of simplicity, high efficiency, environmental protection, etc., and the reaction conditions are mild, without the need for complex reagents and high temperature and high pressure conditions, meeting the requirements of green chemistry. Brief description of the drawings

[0020] Figure 1 The thermogravimetric analysis (TGA) temperature curve shown and Figure 2 the powder X-ray diffraction (PXRD) intensity curve of β -cyclodextrin hydrate crystals verify the Figure 3 , β thermal stability and purity of the -cyclodextrin hydrate crystal structure: a. The β -cyclodextrin hydrate β -CD molecules at 300 K, showing that some hydroxymethyl groups are in a disordered state; b. At 300 K, the O-H··O hydrogen bond interaction between β -cyclodextrin hydrate and H2O molecules forms a one-dimensional channel; c. At 100 K, the β -CD molecules of -CD·11H2O show an ordered state; d. At 100 K, the one-dimensional channel formed by the O-H··O hydrogen bond interaction between β -CD and H2O molecules.

[0021] The colors of C, H, and O atoms are represented by light gray, white, and dark gray, respectively. The H2O molecules located in the one-dimensional channels are shown using a space-filling model. The dashed lines represent O-H··O hydrogen bond interactions. For clarity, the H atoms on the C atoms of the β -CD molecules are omitted.

[0022] Figure 4 , β Ferroelectricity and related properties of a, Results of DSC measurements showing a structural phase transition occurring at around T 0 = 226 K; b, Corresponding data of the real part of the dielectric constant (ɛ') as a function of temperature at different frequencies; c, Temperature dependence of the β -cyclodextrin hydrate dielectric loss (tanδ) at different frequencies; d, β Second harmonic generation (SHG) spectra of -cyclodextrin hydrate crystals excited by 1064 nm fundamental frequency light with different powers. The inset shows the linear fit of the fundamental frequency light power and the logarithmic plot of the SHG signal intensity, with a slope equal to 2.03; e, Polar plot of the total SHG intensity excited by the fundamental frequency light at different polarization angles. The colored dots represent the experimental data, while the solid line represents the theoretical prediction of the SHG intensity as a function of the polarization angle (considering Kleinman symmetry); β f, Polarization-electric field (P-E) hysteresis loop of

[0023] Figure 5 , β -cyclodextrin hydrate crystals along the b axis piezoelectric coefficient d 33 ; Figure 6 , β Microscopic ferroelectric properties of a-c, Topography (a), PFM amplitude (b), and PFM phase (c) images; d-f, PFM phase diagrams in the initial state (d), after applying a +150 V tip voltage in the central region (e), and after applying a -150 V tip voltage in the central region (f).

[0024] Figure 7 , β Piezoelectric properties of a, Measured by resonance-enhanced PFMβ The relationship between the piezoelectric response of β-cyclodextrin hydrate and PVDF and the excitation frequency, and fitting through the damped harmonic oscillator model; b、 β- The relationship curve between the calibration amplitude of cyclodextrin hydrate and PVDF and the excitation voltage; c、 β The impedance and phase angle spectra of the β-cyclodextrin hydrate crystal rod along the

[010] direction; d-f、 β Three-dimensional diagrams of the elastic modulus of β-cyclodextrin hydrate crystals. Three-dimensional diagram of the anisotropic Young's modulus (d). Spatial dependence of the maximum shear modulus (e). Spatial dependence of the minimum shear modulus (f).

[0025] Figure 8 , ferroelectric catalysts synthesize protein amino acids.

[0026] a. Using ferroelectric β β-cyclodextrin hydrate catalyst, all 20 protein amino acids can be obtained from water and neutral atmosphere under normal temperature and pressure with mechanical ultrasonic stimulation, including 2 sulfur-containing amino acids obtained after adding sulfur powder.

[0027] b. Observe the positive ion first-order mass spectrometry spectrum of the product, and observe 11 different protein amino acid signals and their corresponding m / z . The mass spectrometry data is labeled with 15 N. c. Neutralize the special reactant generated by 15 N2 in the reaction.

[0028] d. Summarize the possible mechanism schematic diagram of the reaction of ferroelectric catalysis of water with N2 and CO2 to produce amino acids under ultrasonic stimulation.

[0029] e. The L-enantiomeric excess of aspartic acid (Asp) prepared with β β-cyclodextrin hydrate catalyst ( ee ), while the Asp prepared with the inorganic ferroelectric BTO catalyst is almost a racemic mixture. Specific implementation mode

[0030] To make the technical concept and advantages of the present invention for achieving its invention purpose clearer, the technical solutions of the present invention will be further described in detail below with reference to the drawings. It should be understood that the following embodiments are only used to explain and illustrate the preferred implementation modes of the present invention, and should not be regarded as and do not constitute a limitation on the scope of patent protection required by the present invention.

[0031] The method for synthesizing amino acids by the molecular ferroelectric catalyst of the present invention, the synthesis reaction process includes: Step S1, an excessive amount of molecular ferroelectric crystals (such as cyclic molecular ferroelectricsβ Add (-cyclodextrin hydrate, crown ether derivatives, etc.) into the reaction vessel and add an appropriate amount of water to dissolve it partially; Step S2: Introduce a mixed gas of CO2 and N2 to the bottom of the reaction vessel, and the volume ratio of CO2 to N2 in the mixed gas is 50 - 80%:50 - 20%; Step S3: Apply ultrasonic waves to the reaction system for ultrasonic treatment for 0.8 - 1.2 hours; Use ultrasonic waves (ultrasonic frequency above 40 kHz) to provide mechanical stress; Among them, for the catalyst preparation: Dissolve molecular ferroelectrics in solvents such as water, and obtain high-purity single crystals by slowly evaporating the solvent, which have ferroelectricity and piezoelectricity.

[0032] Reaction system: Gas: CO2 and N2 are mixed (50 - 80%:50 - 20%); Reactant: Sulfur powder with a mass ratio of 3% can be added to the reaction system in step S2 to provide a necessary element source for constructing the structural unit of sulfur-containing amino acids; Solvent: Water or methanol (key reaction medium); Energy input: Ultrasonic waves (above 40 kHz) provide mechanical stress to generate piezoelectric potential. Other mechanical stresses can also be used, such as a stirred reactor, a vibrating disk, a fluidized bed, or a vibrating sieve, etc.

[0033] Reaction mechanism: Molecular ferroelectric crystals (such as cyclic molecular ferroelectrics β -cyclodextrin hydrate, crown ether derivatives, etc.) have a non-centrosymmetric polar crystal structure, in which the ordered arrangement of dipole moments forms a built-in electric field, accompanied by the accumulation of polarization-induced bound charges on both sides. Under mechanical ultrasonic treatment, due to the piezoelectric effect of the molecular ferroelectric crystal, piezoelectric potential is generated, and the generated potential exceeds the inherent reaction energy barrier, thus driving the redox process. During the ultrasonic process, the polarization change of the ferroelectric crystal will also be caused, resulting in the release of free charges on the surface of the ferroelectric domain, and then these free charges quickly interact with the substrate in the solution to promote the redox reaction. Under the action of ultrasonic waves, the free charges released on the surface of the molecular ferroelectric crystal promote the generation of dimer water radical cations (H2O)2 +• The generation of which has a unique two-center three-electron configuration that endows them with strong oxidation ability, and can activate singlet N2 to triplet N2 * and thus interact with (H2O)2 +• to undergo a disproportionation reaction to generate NH2OH. NH2OH is easily protonated in gas-phase chemistry due to its high proton affinity. The generated NH2OH may further react with CO2 to produce amino acids. Since some molecular ferroelectrics such as βThe inherent chirality of the β-cyclodextrin hydrate induces the produced amino acids to have an L-enantiomeric excess, and the reaction is verified to be feasible by 15 N2 isotope.

[0034] Among them, sulfur powder can provide sulfur atoms, participate in the synthesis reaction of amino acids, and provide a necessary elemental source for constructing the structural unit of sulfur-containing amino acids. Sulfur powder interacts with the surface of the iron electrode to form some sites with special catalytic activity or participate in the formation of intermediate products, thus also promoting the synthesis reaction of amino acids. It may change the electron cloud distribution on the surface of the iron electrode, affect the adsorption and reaction activity of reactants on the electrode surface, and act as a cocatalyst.

[0035] Example 1 Prepare β β-cyclodextrin hydrate crystals by a simple room-temperature aqueous solution evaporation method.

[0036] The present invention provides a molecular ferroelectric β β-cyclodextrin hydrate catalytic material for amino acid synthesis, and its preparation process is as follows: Dissolve β β-cyclodextrin hydrate in water, and obtain high-purity single crystals by slowly evaporating the solvent. Its crystal structure is the polar monoclinic space group P P21, and the unit cell parameters are a a = 15.1329 Å, b b = 10.2797 Å, c c = 20.9179 Å, β β = 109.980 ° , V V = 3058.2 Å 3 ).

[0037] The aforementioned obtained molecular ferroelectric β β-cyclodextrin hydrate catalytic material has spontaneous polarization and one-dimensional hydrogen bond channels.

[0038] Figure 1 The shown thermogravimetric analysis (TGA) temperature curve and Figure 2 the shown powder X-ray diffraction (PXRD) intensity curve verify the β thermal stability and purity of the β-cyclodextrin hydrate crystals.

[0039] See Figures 3 - 5 , and obtain β β-cyclodextrin hydrate ( β β-CD·11H2O) by single crystal diffraction and crystallize at room temperature in the polar point group P P21 ( Figure 3 ), and test the differential scanning calorimetry curve, dielectric spectrum, second harmonic, and hysteresis loop of β β-cyclodextrin hydrate, etc.Figure 4 ), and the β piezoelectric coefficient of d 33 β-cyclodextrin hydrate was measured to be 26 pC / N ( Figure 5 ), preliminarily verifying the β ferroelectricity of β-CD·11H2O.

[0040] Through piezoresponse force microscopy (PFM) measurements at room temperature, the ferroelectricity of β β-CD·11H2O was further investigated. Figure 6 a-c show the topography, PFM amplitude, and PFM phase images of a certain area within the thin film sample, indicating the presence of a clear ferroelectric domain structure in the thin film. To study the β ferroelectric polarization reversal behavior of the β-CD·11H2O thin film, we conducted domain reversal experiments. First, a tip voltage of +150 V was applied to the central region, and it was observed that the entire region almost completely flipped to a single-domain state ( Figure 6 e). Subsequently, after applying a reverse tip voltage of -150 V to the same region, the reappearance of new domains was observed ( Figure 6 f), further verifying the β ferroelectricity of β-CD·11H2O.

[0041] Due to the symmetry restrictions of point group 2, there are 13 non-zero coefficients in the elastic stiffness matrix, and the matrix elements are symmetric about the main diagonal. A small elastic stiffness constant indicates that β the β-CD·11H2O crystal is an inherently mechanically soft material. To more intuitively understand the elastic properties, Figure 7 a three-dimensional distribution map of Young's modulus representing uniaxial stiffness in different directions is plotted in d. Obviously, Young's modulus has very large anisotropy, with an irregular double-cone shape. The anisotropy of Young's modulus comes from the ordered arrangement of cyclodextrin molecules related to intermolecular interactions in the crystal structure. In addition, the surface of the spatially dependent minimum shear modulus can be regularly nested within the maximum surface, forming a shell-like structure of the shear modulus ( Figure 7 e, f).

[0042] Example 2 According to the method for catalytic synthesis of amino acids by the molecular ferroelectric of the present invention, 3 g of ferroelectric β β-cyclodextrin hydrate crystals were added to a reaction vessel containing 20 mL of water, and a mixed gas of CO2 and N2 (volume ratio 66.6%:33.3%) was introduced, and ultrasonic treatment was applied at 45 kHz for 1 hour, generating 18 sulfur-free protein amino acids. The reaction mechanism is as shown in Figure 8 d, and the generated Asp protein amino acid shows an L-enantiomeric excess as shown in Figure 8 e.

[0043] Example 3 On the basis of Example 2, in order to introduce sulfur element, sulfur powder was added to the reaction system. The addition amount of sulfur powder was 0.1 g. The above experimental steps were repeated, and all 20 kinds of protein amino acids were further synthesized and improved.

[0044] Example 4 On the basis of Example 2, the volume ratio of CO2 and N2 was adjusted to 1:1, and 0.1 g of sulfur powder was added. The above experimental steps were repeated, and sulfur-containing amino acids methionine and cysteine were successfully synthesized.

[0045] Comparative experiment Using the traditional inorganic ferroelectric material BaTiO3 as a catalyst, experiments were carried out under the same conditions. Only five protein amino acids were detected, and the enantiomeric excess value of L-amino acids was much lower than that of molecular ferroelectrics β -cyclodextrin hydrate catalyst.

[0046] The above examples and comparative experiments fully demonstrate the feasibility and superiority of the method of the present invention, and provide a new perspective and method for the synthesis of amino acids.

[0047] Of course, the above is only a preferred embodiment of the present invention and does not constitute a limitation to the present invention. Those skilled in the art can make other modifications to the implementation of the present invention without creative labor under the guidance of the prior art. Any modification made within the spirit and principle of the present invention or any simple substitution or equivalent replacement using conventional technical means in the art shall be included within the protection scope of the present invention.

Claims

1. A method for synthesizing amino acids using molecular ferroelectric catalysis, characterized in that: The specific steps include: Step S1, adding a molecular ferroelectric catalytic material into a reaction container, and adding a small amount of deionized water to partially dissolve the molecular ferroelectric catalytic material in the reaction container to form an excess state; Step S2, introducing a mixed gas of CO2 and N2 into the bottom of the reaction container, wherein the volume ratio of the mixed gas CO2 and N2 is 50-80%:50-20%; Step S3, treating the reaction system by mechanical vibration for 0.8-1.2 hours. After the reaction is completed, filtering the reaction mixture to obtain the amino acid.

2. The method for synthesizing amino acids using molecular ferroelectric catalysis according to claim 1, characterized in that: In step S2, the volume ratio of the mixed gas CO2 and N2 is 2:

1.

3. The method for synthesizing amino acids using molecular ferroelectric catalysis according to claim 1, characterized in that: In step S2, the volume ratio of the mixed gas CO2 and N2 is 1:

1.

4. The method for synthesizing amino acids by molecular ferroelectric catalysis according to claim 1, 2 or 3, characterized in that: Add 3% by weight of sulfur powder to the reaction system of step S2 to provide a necessary element source for constructing the structural unit of sulfur-containing amino acids.

5. The method for synthesizing amino acids using molecular ferroelectric catalysis according to claim 4, characterized in that: In step S1, the molecular ferroelectric catalytic material is a ring-shaped molecular ferroelectric β - Cyclodextrin hydrate or crown ether derivatives.

6. The method for synthesizing amino acids using molecular ferroelectric catalysis according to claim 1, 2 or 3, characterized in that: In step S1, the molecular ferroelectric catalytic material is a ring-shaped molecular ferroelectric β - Cyclodextrin hydrate or crown ether derivatives.

7. The method for synthesizing amino acids by molecular ferroelectric catalysis according to claim 1, 2, 3 or 5, characterized in that: In step S3, mechanical stress is provided by using mechanical vibration such as ultrasound, and the ultrasound frequency is 40-60 kHz.

8. A molecular ferroelectric catalytic material for amino acid synthesis, characterized in that: The preparation process of the catalytic material is as follows: dissolving a molecular ferroelectric in a solvent such as water, and obtaining a high-purity single crystal by slowly evaporating the solvent, which is used for catalytic synthesis of amino acids.

9. The molecular ferroelectric catalytic material according to claim 8, characterized in that: The molecular ferroelectric crystal is a ring-shaped molecular ferroelectric β - Cyclodextrin hydrate or crown ether derivatives.

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