Chiral high-entropy ceramic electrocatalyst based on ligand-controlled collapse mechanism

Abstract

This invention belongs to the field of nanomaterials and catalytic chemistry, and discloses a chiral high-entropy ceramic electrocatalyst prepared based on a ligand-controlled collapse mechanism. In the synthesis of this catalyst, multiple transition metals are first introduced into a zeolite imidazole ester (ZIF) precursor to construct high-entropy nodes, and then grafted with sterically hindered chiral functional organic ligands exhibiting thermal retardation effects. Through a unique kinetic retardation effect, the metal aggregation rate is slowed down during pyrolysis, allowing the carbon-nitrogen framework to complete directional helical assembly before metal melting, ultimately forming a ceramic structure with atomically high-entropy active sites and macroscopic chiral channels. The catalyst prepared by this invention exhibits high specific surface area and enantioselectivity, making it particularly suitable for the in-situ synthesis of chiral intermediates under extreme aerospace environments.

Description

Technical Field

[0001] This invention belongs to the field of nanomaterials and catalytic chemistry, and in particular relates to a chiral high-entropy ceramic electrocatalyst based on a ligand-controlled collapse mechanism. Background Technology

[0002] In remote areas far from human activity, such as deep space exploration, space travel, ocean shipping, and remote islands, resource acquisition and utilization face enormous challenges. Taking aerospace engineering as an example, spacecraft need to carry large amounts of supplies during long-term flights, including raw materials for synthesizing key substances. Waste from human and industrial emissions is constantly generated in these scenarios. If this waste can be converted into chiral intermediates through electrochemical organic synthesis, it can not only achieve efficient waste utilization and reduce the amount of supplies carried, but also provide the necessary chemical support for the continuous operation of spacecraft. In remote areas, due to inconvenient transportation and difficult supply of materials, the synthesis of chiral intermediates from locally generated waste also has significant practical implications. From a future development perspective, as human demands for resource utilization efficiency continue to increase, this waste reuse method will become an important way to solve resource shortage problems. Therefore, it is urgently necessary to utilize human or industrial waste for electrochemical organic synthesis to prepare chiral intermediates under extreme conditions.

[0003] Traditional electrocatalysts typically lack the ability for chiral synthesis. To achieve chiral synthesis, one approach is to introduce chiral ligands into the reaction system, inducing a chiral environment through the interaction between the ligands and the catalyst. However, this method suffers from problems such as easy loss of chiral ligands and poor stability, making it difficult to maintain chiral selectivity consistently. Another approach is to modify the catalyst surface to impart a chiral structure, but this modification process is complex, difficult to synthesize, and the activity of the modified catalyst is often affected to some extent. Furthermore, chiral synthesis can be induced by designing specific reaction conditions, but these conditions are usually quite demanding and difficult to widely implement in practical applications.

[0004] Invention CN110433867A discloses a method for preparing a chiral Cu / Zn-MOF / NiF nanocomposite catalyst and its application in the asymmetric electroreduction of acetophenone. However, this catalyst and synthesis method can only be carried out in a mixed solution of quaternary ammonium salt and acetophenone, and the obtained product needs to be extracted with anhydrous diethyl ether, resulting in low efficiency, high energy consumption, and poor stability. Invention CN111408414A discloses a method for preparing a CuO / Ce2O3 hybrid chiral Cu-MOF core-shell nanocomposite material, similar to CN110433867A, which is also used for the synthesis of aromatic ketones, but also has similar defects. Invention CN113896898A provides a method for preparing a two-dimensional chiral nickel-based metal-organic framework material. The prepared chiral Ni-MOF material is stable as an electrocatalyst and has excellent electrocatalytic activity for the oxidation of methanol, ethanol, and n-propanol, but it does not have the ability to electrosynthesize chiral organic compounds. Invention CN113716630A discloses a method for preparing two-dimensional chiral nickel hydroxide nanosheets. By selecting suitable chiral molecules as structure directing agents, chiral inorganic nanomaterials can be prepared, thereby enabling the selection of electronic spin states and the regulation of crystal nucleation and growth rates. However, it does not have the ability to synthesize chiral materials.

[0005] In summary, the current research and technical solutions still have significant shortcomings, as detailed below:

[0006] 1) Most existing electrocatalysts can only function in specific reaction systems, making it difficult to achieve the effective synthesis of chiral intermediates in different systems. This greatly limits their application scenarios and scope, and fails to meet the diverse synthesis needs under extreme conditions.

[0007] 2) Some synthesis methods are inefficient and have high energy consumption. The post-processing of the products is complicated, which increases the cost and complexity of the production process and is not conducive to large-scale industrial production.

[0008] 3) Although some catalysts exhibit certain performance characteristics in certain aspects, most of them lack the ability to electrosynthesize chiral organic compounds, thus failing to achieve the goal of preparing chiral intermediates through electrochemical organic synthesis and failing to meet the requirements of practical applications for the chiral synthesis function of catalysts. Summary of the Invention

[0009] This invention addresses the problems existing in the prior art. Existing chiral electrocatalysts, when used in electrochemical organic synthesis to prepare chiral intermediates under extreme conditions, suffer from narrow applicability, low synthesis efficiency, high energy consumption, and insufficient chiral synthesis capability. This invention, based on a ligand-controlled collapse mechanism, utilizes a unique kinetic retardation effect to slow down the metal aggregation rate. It employs the screening and synthesis of chiral organic ligands with specific properties, characterized by a small rigidity twist angle and high thermal stability, providing stable support for the pyrolysis process. By introducing the synergistic regulation of a hypergravity field and a thermochemical field during pyrolysis, the catalyst structure is precisely designed at the molecular level, enabling the carbon-nitrogen framework to complete directional chiral helical assembly before metal melting. Based on this, this invention constructs a ceramic structure where atomically high-entropy active sites coexist with macroscopic chiral channels. In this structure, the high-entropy active sites are composed of five transition metals: cobalt, nickel, copper, iron, and zinc, providing abundant active centers for the reaction. The chiral channels provide pathways for reactants to enter and react, ensuring that reactants can react smoothly on the chirally arranged high-entropy active centers.

[0010] To achieve the above objectives, the present invention provides a chiral high-entropy ceramic electrocatalyst based on a ligand-controlled collapse mechanism, characterized in that the preparation method of the catalyst specifically includes the following steps:

[0011] Step 1: Select organic molecules with chiral purity of not less than 99%, structural rigidity with a torsion angle of less than 10°, thermal stability with a mass loss of less than 5% at 400℃, and containing 10-20 C atoms, 2-5 N atoms, 10-30 H atoms, and 1-3 O atoms as chiral ligands. The chiral ligand molecules are one of the following: 2,2'-binaphthol derivative, chiral ferrocene derivative, chiral spirocyclic diol derivative, chiral porphyrin derivative, or chiral crown ether derivative. They must have the ability to coordinate with transition metals and their chiral structure must not be easily destroyed.

[0012] Step 2: Prepare the zeolite imidazole ester (ZIF) precursor by dissolving zinc nitrate in methanol at a concentration of 0.1 mol / L to form a metal salt solution, adding 2-methylimidazole at a molar ratio of 4:1 to zinc nitrate, and reacting for 18 h at a temperature of 60℃, a stirring speed of 300 r / min, and a pH of 7-8 to obtain the ZIF precursor solution.

[0013] Step 3: The chiral ligands obtained in Step 1 are added to the ZIF precursor solution prepared in Step 2, along with four transition metal nitrates: cobalt nitrate, nickel nitrate, copper nitrate, and iron nitrate. The molar ratio of the four transition metal nitrates is 1:1:1:1, the mass ratio of the chiral ligands to the ZIF precursor solution is 1:50, and the total molar ratio of the chiral ligands to the four transition metal nitrates is 1:2. The reaction is carried out at 75℃, 400 r / min, and pH 7.5–8.5 for 12 h. During the reaction, the solution gradually turns dark brown. At the end of the reaction, a dark brown precipitate is obtained. The precipitate is filtered and washed to graft the chiral ligands and transition metals onto the ZIF precursor, constructing high-entropy nodes.

[0014] Step 4: Separate and wash the product obtained in Step 3 to remove unreacted impurities; dry the product at 100°C under vacuum for 18 h to ensure it is fully dried.

[0015] Step 5: The pretreated product obtained in step 4 is placed into a high-gravity rotating packed bed pyrolysis furnace. A high-gravity field with a centrifugal acceleration of 3000 g is generated by the high-gravity rotating packed bed. The pyrolysis furnace is controlled by a programmable temperature controller to achieve programmed temperature control of the thermochemical field. Under nitrogen atmosphere protection, the temperature is increased from room temperature to 350℃ at a rate of 7℃ / min and held for 45 min. Then, the temperature is increased to 900℃ at a rate of 3℃ / min and held for 2 h.

[0016] Step 6: Precisely control the chiral helical assembly of the carbon-nitrogen framework. During pyrolysis, the reaction conditions are controlled by the synergistic effect of the supergravity field and the thermochemical field, so that the carbon-nitrogen framework completes the directional chiral helical assembly before the metal melts.

[0017] Step 7: After pyrolysis, the product is cooled to room temperature, forming a ceramic structure where atomically high-entropy active sites and macroscopic chiral channels coexist. The presence of uniformly distributed bright spots observed by high-resolution transmission electron microscopy confirms the formation of atomically high-entropy active sites. Mercury intrusion porosimetry measurements show that the chiral channel pore size distribution is between 2 and 50 nm, and the pore volume is between 0.2 and 0.5 cm³. 3 / g indicates the formation of a porous structure; the difference in absorption of left and right circularly polarized light by solid circular dichroism spectroscopy indicates that a stable chiral helical structure has been formed in the carbon-nitrogen framework; the high-entropy active sites are composed of five transition metals, cobalt, nickel, copper, iron and zinc, which are uniformly distributed in the ceramic structure, and the chiral channels provide reaction channels for the reactants;

[0018] Step 8: Soak the chiral high-entropy ceramic electrocatalyst prepared in Step 7 in 0.1 mol / L hydrochloric acid solution for 2 h, wash with deionized water until neutral, then soak in 0.05 mol / L sodium hydroxide solution for 1 h, and wash with deionized water until neutral; test the catalytic activity by cyclic voltammetry and the enantioselectivity by high performance liquid chromatography; adjust the preparation process parameters according to the test results to improve the specific surface area and enantioselectivity of the catalyst.

[0019] The chiral high-entropy ceramic electrocatalyst based on the ligand-controlled collapse mechanism according to claim 1 is characterized in that the chiral organic ligand in step 1 is preferably a chiral organic ligand with a chiral purity of 99.5%, a structural rigidity torsion angle of 5°, and a thermal stability with a mass loss of less than 3% at 400°C.

[0020] Furthermore, the chiral organic ligand described in step 1 is preferably a chiral organic ligand with a chiral purity of 99.5%, a structural rigidity torsion angle of 5°, and a thermal stability of less than 3% mass loss at 400°C.

[0021] The advantages of this invention are:

[0022] 1) The unique ligand design and multi-field regulation of the ceramic structure give the catalyst good stability, enabling it to maintain stable performance under extreme conditions and to be used for a long time without significant decrease in activity and selectivity.

[0023] 2) The synergistic effect of high-entropy active sites and chiral channels significantly improves the catalytic activity and enantioselectivity of the catalyst, enabling efficient synthesis of chiral intermediates.

[0024] 3) Catalysts are not limited to specific reaction systems and can function under various conditions. They can be widely used in the electrochemical synthesis of chiral intermediates in extreme environments such as aerospace and remote areas. Attached Figure Description

[0025] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention.

[0026] Figure 1 This describes the synthetic steps for chiral high-entropy ceramic electrocatalysts based on a ligand-controlled collapse mechanism.

[0027] Figure 2 This is a transmission electron microscope image of a chiral high-entropy ceramic electrocatalyst based on a ligand-controlled collapse mechanism.

[0028] Figure 3 This is a scanning electron microscope image of a chiral high-entropy ceramic electrocatalyst based on a ligand-controlled collapse mechanism.

[0029] Figure 4 To improve the efficiency and selectivity of chiral high-entropy ceramic electrocatalysts based on ligand-controlled collapse mechanism in the synthesis of L-serine.

[0030] Figure 5 To improve the efficiency and selectivity of chiral high-entropy ceramic electrocatalysts based on ligand-controlled collapse mechanism in the synthesis of L-type tyrosine. Detailed Implementation

[0031] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0032] As an embodiment of the present invention, a chiral high-entropy ceramic electrocatalyst based on a ligand-controlled collapse mechanism is described in the attached process. Figure 1 As shown, the specific steps include the following:

[0033] Step 1: Select organic molecules with a chiral purity of not less than 99%, a structural rigidity with a torsion angle of less than 10°, a thermal stability with a mass loss of less than 5% at 400℃, and containing 10-20 C atoms, 2-5 N atoms, 10-30 H atoms, and 1-3 O atoms as chiral ligands. The chiral ligand molecules are one of the following: 2,2'-binaphthol derivatives, chiral ferrocene derivatives, chiral spirocyclic diol derivatives, chiral porphyrin derivatives, and chiral crown ether derivatives. They should have the ability to coordinate with transition metals and their chiral structure should not be easily destroyed. Preferably, the chiral organic ligands have a chiral purity of 99.5%, a structural rigidity with a torsion angle of 5°, and a thermal stability with a mass loss of less than 3% at 400℃.

[0034] Step 2: Prepare the zeolite imidazole ester (ZIF) precursor by dissolving zinc nitrate in methanol at a concentration of 0.1 mol / L to form a metal salt solution, adding 2-methylimidazole at a molar ratio of 4:1 to zinc nitrate, and reacting for 18 h at a temperature of 60℃, a stirring speed of 300 r / min, and a pH of 7-8 to obtain the ZIF precursor solution.

[0035] Step 3: The chiral ligands obtained in Step 1 are added to the ZIF precursor solution prepared in Step 2, along with four transition metal nitrates: cobalt nitrate, nickel nitrate, copper nitrate, and iron nitrate. The molar ratio of the four transition metal nitrates is 1:1:1:1, the mass ratio of the chiral ligands to the ZIF precursor solution is 1:50, and the total molar ratio of the chiral ligands to the four transition metal nitrates is 1:2. The reaction is carried out at 75℃, 400 r / min, and pH 7.5–8.5 for 12 h. During the reaction, the solution gradually turns dark brown. At the end of the reaction, a dark brown precipitate is obtained. The precipitate is filtered and washed to graft the chiral ligands and transition metals onto the ZIF precursor, constructing high-entropy nodes.

[0036] Step 4: Separate and wash the product obtained in Step 3 to remove unreacted impurities; dry the product at 100°C under vacuum for 18 h to ensure it is fully dried.

[0037] Step 5: The pretreated product obtained in step 4 is placed into a high-gravity rotating packed bed pyrolysis furnace. A high-gravity field with a centrifugal acceleration of 3000 g is generated by the high-gravity rotating packed bed. The pyrolysis furnace is controlled by a programmable temperature controller to achieve programmed temperature control of the thermochemical field. Under nitrogen atmosphere protection, the temperature is increased from room temperature to 350℃ at a rate of 7℃ / min and held for 45 min. Then, the temperature is increased to 900℃ at a rate of 3℃ / min and held for 2 h.

[0038] Step 6: Precisely control the chiral helical assembly of the carbon-nitrogen framework. During pyrolysis, the reaction conditions are controlled by the synergistic effect of the supergravity field and the thermochemical field, so that the carbon-nitrogen framework completes the directional chiral helical assembly before the metal melts.

[0039] Step 7: After pyrolysis, the product is cooled to room temperature, forming a ceramic structure where atomically high-entropy active sites and macroscopic chiral channels coexist. The presence of uniformly distributed bright spots observed by high-resolution transmission electron microscopy confirms the formation of atomically high-entropy active sites. Mercury intrusion porosimetry measurements show that the chiral channel pore size distribution is between 2 and 50 nm, and the pore volume is between 0.2 and 0.5 cm³. 3 / g indicates the formation of a porous structure; the difference in absorption of left and right circularly polarized light by solid circular dichroism spectroscopy indicates that a stable chiral helical structure has been formed in the carbon-nitrogen framework; the high-entropy active sites are composed of five transition metals, cobalt, nickel, copper, iron and zinc, which are uniformly distributed in the ceramic structure, and the chiral channels provide reaction channels for the reactants;

[0040] Step 8: Soak the chiral high-entropy ceramic electrocatalyst prepared in Step 7 in 0.1 mol / L hydrochloric acid solution for 2 h, wash with deionized water until neutral, then soak in 0.05 mol / L sodium hydroxide solution for 1 h, and wash with deionized water until neutral; test the catalytic activity by cyclic voltammetry and the enantioselectivity by high performance liquid chromatography; adjust the preparation process parameters according to the test results to improve the specific surface area and enantioselectivity of the catalyst.

[0041] The chiral high-entropy ceramic electrocatalyst based on the ligand-controlled collapse mechanism according to claim 1 is characterized in that the chiral organic ligand in step 1 is preferably a chiral organic ligand with a chiral purity of 99.5%, a structural rigidity torsion angle of 5°, and a thermal stability with a mass loss of less than 3% at 400°C.

[0042] The embodiments of the present invention will be further described below with reference to specific examples.

[0043] Example 1

[0044] A 2,2'-binaphthol derivative with a chiral purity of 99%, a structural rigidity with a torsion angle of 8°, a thermal stability of 4% at 400℃ with a mass loss of 4%, and containing 15 C atoms, 3 N atoms, 20 H atoms, and 2 O atoms was selected as the chiral ligand. Zinc nitrate was dissolved in methanol at a concentration of 0.1 mol / L to form a metal salt solution. 2-Methylimidazole was added, with a molar ratio of 2-methylimidazole to zinc nitrate of 4:1. The reaction was carried out at 60℃, a stirring speed of 300 r / min, and a pH of 7.5 for 18 h to obtain a ZIF precursor solution. The synthesized chiral organic ligand was added to the ZIF precursor solution, along with cobalt nitrate, nickel nitrate, copper nitrate, and ferric nitrate, with a molar ratio of the four transition metal salts of 1:1:1:1. The mass ratio of the chiral ligand to the ZIF precursor solution was 1:50, and the total molar ratio of the chiral ligand to the four transition metal nitrates was 1:2. The reaction was carried out at 75℃ and a stirring speed of 400 r / min. The reaction was carried out at r / min and pH 8.5 for 12 h. The dark brown precipitate was filtered and washed. The product was separated, washed, and dried at 100℃ under vacuum for 18 h. The pretreated product was placed in a high-gravity rotating packed bed pyrolysis furnace to generate a high-gravity field with a centrifugal acceleration of 3000 g. The temperature was programmed to rise from room temperature to 350℃ at a rate of 7℃ / min and held for 45 min, then to 900℃ at a rate of 3℃ / min and held for 2 h. After pyrolysis, the product was cooled to room temperature. The formation of atomic-level high-entropy active sites was confirmed by high-resolution transmission electron microscopy. The formation of pore structure was confirmed by mercury intrusion porosimetry. The formation of a stable chiral helical structure of carbon-nitrogen framework was confirmed by solid-state circular dichroism spectroscopy. The product was soaked in 0.1 mol / L hydrochloric acid solution for 2 h, washed with deionized water until neutral, and then soaked in 0.05 mol / L sodium hydroxide solution for 1 h and washed with deionized water until neutral.

[0045] As attached Figure 2 , 3 As shown, the obtained chiral high-entropy ceramic electrocatalyst exhibits a right-handed twisted 18-hedron structure, exhibiting typical chiral characteristics. The surface shows certain wrinkles, which are caused by organic condensation during pyrolysis. In the synthesis of L-serine, this catalyst demonstrates high efficiency, achieving a conversion efficiency of 85% and an enantioselectivity as high as 95% after 8 hours of full activation (see Appendix). Figure 4 ).

[0046] Example 2

[0047] This embodiment is a variation of Example 1, the difference being that the chiral organic ligand screened is a chiral ferrocene derivative with a chiral purity of 99.5%, a structural rigidity with a torsion angle of 5°, and a thermal stability with a mass loss of 3% at 400°C, containing 10 C atoms, 2 N atoms, 10 H atoms, and 1 O atom in the molecule; the pH value is 8 when preparing the ZIF precursor; the pH value is 7.5 when introducing the high-entropy node and reacting with the chiral ligand; other conditions are the same as in Example 1, and will not be repeated.

[0048] The resulting electrocatalyst exhibits a left-handed twisted icosahedron with more pronounced surface wrinkles and more prominent chiral characteristics. In the synthesis of L-tyrosine, after full catalyst activation, the conversion efficiency increased to 84%, and the enantioselectivity reached 97%.

[0049] Example 3

[0050] This embodiment is a variation of Example 1, the difference being that the chiral organic ligand selected is a chiral spirocyclic diphenol derivative with a chiral purity of 99.5%, a structural rigidity with a torsion angle of 5°, and a thermal stability with a mass loss of 3% at 400°C, containing 20 C atoms, 5 N atoms, 30 H atoms, and 3 O atoms in the molecule; the pH value is 7 when preparing the ZIF precursor; the pH value is 8 when introducing the high-entropy node and reacting with the chiral ligand; other conditions are the same as in Example 1, and will not be repeated.

[0051] The resulting electrocatalyst exhibits an irregular chiral polyhedron with a relatively rough surface. In the synthesis of L-proline, it achieves a conversion efficiency of 83% and an enantioselectivity of 90%.

[0052] Example 4

[0053] This embodiment is a variation of Example 1, the difference being that the chiral organic ligand selected is a chiral porphyrin derivative with a chiral purity of 99%, a structural rigidity with a torsion angle of 8°, and a thermal stability of 4.5% mass loss at 400°C, containing 17 C atoms, 4 N atoms, 20 H atoms, and 2 O atoms in the molecule; the pH value is 7.2 when preparing the ZIF precursor; the pH value is 8.1 when introducing the high-entropy node and reacting with the chiral ligand; other conditions are the same as in Example 1, and will not be repeated.

[0054] The resulting electrocatalyst exhibits a helical-like structure and significant chiral characteristics. In the synthesis of 6-deoxy-L-mannose, it achieves a conversion efficiency of 86% and an enantioselectivity of 93%.

[0055] Example 5

[0056] This embodiment is a variation of Example 1, the difference being that the selected chiral organic ligand is a chiral crown ether derivative with a chiral purity of 99.5%, a structural rigidity torsion angle of 9°, and a thermal stability of 2% mass loss at 400°C, containing 12 C atoms, 3 N atoms, 12 H atoms, and 2 O atoms in the molecule; the pH value is 7.5 when preparing the ZIF precursor; the pH value is 8.2 when introducing the high-entropy node and reacting with the chiral ligand; other conditions are the same as in Example 1, and will not be repeated.

[0057] The resulting electrocatalyst exhibits a nearly spherical chiral structure with slight surface undulations. In the synthesis of L-asparagine, it achieved a conversion efficiency of 84% and an enantioselectivity of 91%.

[0058] The specific embodiments described above are only used to illustrate the spirit of the present invention. The scope of protection of the present invention is not limited thereto. For those skilled in the art, other embodiments can be easily made by means of changes, substitutions or modifications based on the technical content disclosed in this specification. All such other embodiments should be covered within the scope of protection of the present invention.

Claims

1. A chiral high-entropy ceramic electrocatalyst based on ligand-controlled collapse mechanism, characterized in that The preparation method of this catalyst specifically includes the following steps: Step 1: Select organic molecules with chiral purity of not less than 99%, structural rigidity with a torsion angle of less than 10°, thermal stability with a mass loss of less than 5% at 400℃, and containing 10-20 C atoms, 2-5 N atoms, 10-30 H atoms, and 1-3 O atoms as chiral ligands. The chiral ligand molecules are one of the following: 2,2'-binaphthol derivative, chiral ferrocene derivative, chiral spirocyclic diol derivative, chiral porphyrin derivative, or chiral crown ether derivative. They must have the ability to coordinate with transition metals and their chiral structure must not be easily destroyed. Step 2: Prepare the zeolite imidazole ester (ZIF) precursor by dissolving zinc nitrate in methanol at a concentration of 0.1 mol / L to form a metal salt solution, adding 2-methylimidazole at a molar ratio of 4:1 to zinc nitrate, and reacting at 60℃, stirring speed of 300 r / min, and pH of 7-8 for 18 h to obtain the ZIF precursor solution. Step 3: The chiral ligands obtained in Step 1 are added to the ZIF precursor solution prepared in Step 2, along with four transition metal nitrates: cobalt nitrate, nickel nitrate, copper nitrate, and iron nitrate. The molar ratio of the four transition metal nitrates is 1:1:1:1, the mass ratio of the chiral ligands to the ZIF precursor solution is 1:50, and the total molar ratio of the chiral ligands to the four transition metal nitrates is 1:

2. The reaction is carried out at 75℃, 400 r / min, and pH 7.5–8.5 for 12 h. During the reaction, the solution gradually turns dark brown. At the end of the reaction, a dark brown precipitate is obtained. The precipitate is filtered and washed to graft the chiral ligands and transition metals onto the ZIF precursor, constructing high-entropy nodes. Step 4: Separate and wash the product obtained in Step 3 to remove unreacted impurities; dry the product at 100°C under vacuum for 18 hours to ensure it is fully dried. Step 5: The pretreated product obtained in step 4 is placed into a high-gravity rotating packed bed pyrolysis furnace. A high-gravity field with a centrifugal acceleration of 3000 g is generated by the high-gravity rotating packed bed. The pyrolysis furnace is controlled by a programmable temperature controller to achieve programmed temperature control of the thermochemical field. Under nitrogen atmosphere protection, the temperature is increased from room temperature to 350℃ at a rate of 7℃ / min and held for 45 min. Then, the temperature is increased to 900℃ at a rate of 3℃ / min and held for 2 h. Step 6: Precisely control the chiral helical assembly of the carbon-nitrogen framework. During pyrolysis, the reaction conditions are controlled by the synergistic effect of the supergravity field and the thermochemical field, so that the carbon-nitrogen framework completes the directional chiral helical assembly before the metal melts. Step 7: After pyrolysis, the product is cooled to room temperature, forming a ceramic structure in which atomically high-entropy active sites and macroscopic chiral channels coexist. The presence of uniformly distributed bright spots observed by high-resolution transmission electron microscopy confirms the formation of atomically high-entropy active sites. Measurement of the chiral channel diameter using mercury intrusion porosimetry confirms the formation of a pore structure. Detection of the absorption difference of the solid to left and right circularly polarized light using solid-state circular dichroism spectroscopy indicates the formation of a stable chiral helical structure within the carbon-nitrogen framework. The high-entropy active sites are composed of five transition metals: cobalt, nickel, copper, iron, and zinc, uniformly distributed within the ceramic structure, while the chiral channels provide reaction pathways for the reactants. Step 8: Soak the chiral high-entropy ceramic electrocatalyst prepared in Step 7 in 0.1 mol / L hydrochloric acid solution for 2 h, wash with deionized water until neutral, then soak in 0.05 mol / L sodium hydroxide solution for 1 h, and wash with deionized water until neutral; test the catalytic activity by cyclic voltammetry and the enantioselectivity by high performance liquid chromatography; adjust the preparation process parameters according to the test results to improve the specific surface area and enantioselectivity of the catalyst.

2. The chiral high-entropy ceramic electrocatalyst based on ligand-controlled collapse mechanism according to claim 1, characterized in that, The chiral organic ligands mentioned in step 1 are preferably chiral organic ligands with a chiral purity of 99.5%, a structural rigidity torsion angle of 5°, and a thermal stability of less than 3% mass loss at 400°C.

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