Chiral oxide as well as preparation method and electro-catalysis application thereof

Abstract

The invention belongs to the technical field of catalysts, and discloses a chiral oxide as well as a preparation method and electro-catalysis application thereof. The chemical formula of the chiral oxide is Co (3-x) MxO4, M is a transition metal element and a non-noble metal element, and x is greater than or equal to 0 and less than 3. The g factor of the chiral oxide disclosed by the invention can reach 10 <-2 > magnitude order, which is one magnitude order higher than that of the existing chiral material. Compared with a racemization catalyst, the spin selective effect induced by the chiral oxide spontaneously promotes spin polarization of electrons, and is beneficial to directional transmission of spin electrons in electrolyzed water to form spin current, so that efficient generation of paramagnetic oxygen is promoted. In addition, the size of the chiral oxide is 2-5 nm, and due to the extremely small particle size, the chiral oxide has great advantages in the field of electro-catalysis.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalysts, and in particular relates to a chiral oxide, a preparation method thereof, and electrocatalytic applications thereof. Background Art

[0002] With the continuous consumption of non-renewable energy such as fossil fuels, the development of renewable clean energy such as hydrogen energy is an important way to solve this crisis. Among them, water electrolysis technology plays a core role in the hydrogen production industry. Since the anode of water electrolysis involves multiple intermediates and multiple electron transfer processes, its slow reaction kinetics directly limits the efficiency of hydrogen production by water electrolysis. Therefore, the development of low-cost, high-performance anode oxygen evolution reaction catalysts has become the key to the promotion of hydrogen energy. At present, the design of catalysts mainly regulates the adsorption and desorption equilibrium between catalysts and intermediates from a thermodynamic perspective, while ignoring the influence of electron spin properties on reaction kinetics. This makes the catalyst performance limited to the traditional linear scaling relationship, and it is difficult to break through the volcano curve limitation based on Sabatier theory.

[0003] Imparting chirality to materials can directly induce electron spin polarization by optimizing the band structure. This opens up spin dynamics pathways during the reaction, potentially breaking through the performance limitations of traditional volcanic apex catalysts and creating new opportunities for achieving even greater efficiency gains in the spin-dependent oxygen evolution reaction. However, the development of low-cost chiral nanocatalysts faces the following challenges: 1) Chiral structures are typically found in precious metal systems such as gold and silver, which are extremely expensive; 2) Chiral structures are more easily formed in micron- or even centimeter-scale materials, making it difficult to couple chiral structures into catalytically advantageous nanomaterials.

[0004] Therefore, achieving controllable synthesis of intrinsic chiral nanocatalysts of non-precious metals is not only expected to achieve a significant breakthrough in catalytic performance, but also helps to further clarify the regulatory mechanism of spin on the kinetics of oxygen evolution reaction, which is of great significance for scientific research and engineering applications. Summary of the Invention

[0005] The present invention aims to address at least one of the technical problems existing in the aforementioned prior art. To this end, the present invention provides a chiral oxide, a preparation method thereof, and electrocatalytic applications thereof. The chiral oxide of the present invention is made from raw materials that do not contain precious metals, resulting in a low production cost.

[0006] The chiral oxide of the present invention is a chiral nano-oxide Co 3-x M x O4 (M represents a transition metal element such as Co, Fe, or Ni) has intrinsic chirality. By coordinating a chiral small molecule to the metal oxide core, the chirality of the small molecule ligand is transferred to the core through the interaction between the two to achieve the chirality of the core oxide. The g factor of the chiral oxide of the present invention can reach 10 -2Compared to racemic catalysts, the chiral oxides of the present invention induce a spin-selective (CISS) effect that spontaneously promotes electron spin polarization, facilitating the directional transport of spin electrons in water electrolysis to form spin currents, thereby promoting the efficient generation of paramagnetic oxygen. Furthermore, the chiral oxides of the present invention have a particle size of 2-5 nm, making them extremely advantageous in the field of electrocatalysis. Therefore, the chiral oxides of the present invention exhibit superior catalytic activity and faster electron transfer kinetics compared to racemic oxides of the same species.

[0007] A first aspect of the present invention provides a chiral oxide.

[0008] A chiral oxide with the chemical formula Co 3-x M x O4, wherein M is a transition metal element and a non-precious metal element, and x is greater than or equal to 0 and less than 3.

[0009] Preferably, the M is selected from at least one of Co, Fe, and Ni.

[0010] Preferably, the chiral oxide is nano-scale particles.

[0011] Preferably, the size of the chiral oxide is 1-10 nm, more preferably 2-5 nm.

[0012] Preferably, the chiral g factor of the chiral oxide is up to 10 -2 Magnitude.

[0013] Preferably, the chiral oxide is selected from D / L-Co3O4, racemic DL-Co3O4, D / L-Co 2.4 Fe 0.6 O4, racemic DL-Co 2.4 Fe 0.6 O4、D / L-Co 2.4 Ni 0.6 O4, racemic DL-Co 2.4 Ni 0.6 At least one of O4.

[0014] A second aspect of the present invention provides a method for preparing a chiral oxide.

[0015] A method for preparing a chiral oxide comprises the following steps: (1) Prepare reducing agent solution, chiral small molecule solution, complexing agent solution and metal salt solution respectively and set aside; (2) adding water to the container, and then adding the reducing agent solution, chiral small molecule solution, complexing agent solution and metal salt solution, stirring and mixing, centrifuging to obtain a solid, and drying to obtain the chiral oxide; The chiral small molecule in the chiral small molecule solution is selected from at least one of cysteine, threonine and penicillamine.

[0016] Preferably, the reducing agent in the reducing agent solution is selected from at least one of sodium borohydride, sodium hydroxide, and potassium hydroxide. More preferably, the reducing agent is sodium borohydride. Sodium borohydride can not only serve as a reducing agent but also adjust the pH value of the reaction system.

[0017] Preferably, the complexing agent in the complexing agent solution is selected from sodium citrate or sodium citrate hydrate.

[0018] Preferably, the metal salt in the metal salt solution is selected from at least one of transition metal chlorides, transition metal nitrates, and transition metal sulfates. Further preferably, the metal salt is a transition metal chloride (such as cobalt chloride, ferric chloride, nickel chloride, etc.).

[0019] Preferably, the concentration of the reducing agent solution is 0.05-0.3 mol / L, more preferably 0.05-0.2 mol / L.

[0020] Preferably, the concentration of the chiral small molecule solution is 0.01-0.6 mol / L, more preferably 0.01-0.5 mol / L.

[0021] Preferably, the concentration of the complexing agent solution is preferably 0.05-0.6 mol / L, more preferably 0.05-0.5 mol / L; Preferably, the concentration of the metal salt solution is preferably 0.05-0.6 mol / L, more preferably 0.05-0.5 mol / L.

[0022] Preferably, in step (2), the volume ratio of the reducing agent solution, the chiral small molecule solution, the complexing agent solution and the metal salt solution is 1-30: (1-18): (1-12): (0.5-12), and more preferably 1-20: (1-15): (1-10): (0.5-10).

[0023] Preferably, the preparation method comprises the following steps: (1) Dissolve the reducing agent, complexing agent, chiral small molecule, and metal salt in deionized water respectively, and stir to form a reducing agent solution, a chiral small molecule solution, a complexing agent solution, and a metal salt solution; (2) Add 50 mL of deionized water to the container, and add the reducing agent solution, chiral small molecule solution, complexing agent solution and metal salt solution obtained in step (1) in sequence at a certain speed. Stir for 3-5 minutes after adding each solution before adding the next solution. Finally, the solution changes from transparent to brown-black to form a mixed solution. (3) After the mixed solution obtained in step (2) is stirred at a certain temperature for a certain period of time, it is observed that the solution becomes a suspension and the color becomes slightly darker; (4) The suspension obtained in step (3) is purified, precipitated, centrifuged, and then vacuum-dried overnight to obtain a powdered chiral oxide.

[0024] Preferably, in step (3), the stirring temperature is 20-30° C., and the stirring time is 2-5 hours.

[0025] The third aspect of the present invention provides an application of a chiral oxide.

[0026] Application of the above chiral oxides in the field of electrocatalysis.

[0027] Preferably, the application refers to using the chiral oxide as an anode catalyst for water electrolysis.

[0028] Compared with the prior art, the present invention has the following beneficial effects: The raw materials used for the chiral oxide of the present invention do not contain precious metals and have low preparation cost.

[0029] (1) The chiral oxide of the present invention is a chiral nano-oxide Co 3-x M x O4 (M represents a transition metal element such as Co, Fe, Ni) has intrinsic chirality. By coordinating a chiral small molecule to the metal oxide core, the chirality of the small molecule ligand is transferred to the core through the interaction between the two to achieve the chirality of the core oxide. The g factor of the chiral oxide of the present invention can reach 10 -2 Compared to racemic catalysts, the chiral oxides of the present invention induce a spin-selective (CISS) effect that spontaneously promotes electron spin polarization, facilitating the directional transport of spin electrons in water electrolysis to form spin currents, thereby promoting the efficient generation of paramagnetic oxygen. Furthermore, the chiral oxides of the present invention have a particle size of 2-5 nm, making them extremely advantageous in the field of electrocatalysis. Therefore, the chiral oxides of the present invention exhibit superior catalytic activity and faster electron transfer kinetics compared to racemic oxides of the same species.

[0030] (2) The preparation method of the chiral oxide described in the present invention is simple, green and environmentally friendly, short in time and low in cost, and has engineering application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a Raman spectrum of the dextrorotatory / levorotatory / racemic (D / L / DL)-Co3O4 nanoparticles prepared in Example 1; Figure 2 This is the UV absorption spectrum of the D / L / DL-Co3O4 nanoparticles prepared in Example 1; Figure 3 Circular dichroism spectra and chiral g-factor diagram of D / L / DL-Co3O4 nanoparticles prepared in Example 1; Figure 4 This is a transmission electron micrograph of the D / L / DL-Co3O4 nanoparticles prepared in Example 1; Figure 5 D / L / DL-Co prepared in Example 2 2.4 Fe 0.6 Circular dichroism spectra and chiral g-factor diagrams of O4 nanoparticles; Figure 6 D / L / DL-Co prepared in Example 3 2.4 Ni 0.6 Circular dichroism spectra and chiral g-factor diagrams of O4 nanoparticles; Figure 7 This is a linear sweep voltammetry curve of Example 4 using D / L / DL-Co3O4 nanoparticles as an anode catalyst for water electrolysis; Figure 8 This is the Tafel slope plot of Example 4 using D / L / DL-Co3O4 nanoparticles as anode catalyst for water electrolysis; Figure 9 Circular dichroism spectrum of D / L / DL-Co3O4-2 nanoparticles prepared in Comparative Example 1; Figure 10 This is the linear sweep voltammogram of the D / L / DL-Co3O4-2 nanoparticles prepared in Comparative Example 1 as an anode catalyst for water electrolysis. DETAILED DESCRIPTION

[0032] In order to make the technical solution of the present invention more clearly understood by those skilled in the art, the following examples are given for illustration. It should be noted that the following examples do not limit the scope of protection claimed by the present invention.

[0033] Unless otherwise specified, the raw materials, reagents, or devices used in the following examples can be obtained from conventional commercial sources or by existing known methods.

[0034] The present invention provides Raman spectra, UV spectra, circular dichroism spectra, electron microscope images of the above-mentioned chiral oxide nanoparticles, and electrochemical tests of the catalytic electrolysis of water. Raman magnetic tests of the chiral oxide confirm that the oxide has a spinel structure. UV spectra and circular dichroism spectra confirm the intrinsic chirality of the oxide, indicating that electron spin polarization is achieved based on the CISS effect. Transmission electron microscopy confirms the nanostructure of the chiral oxide. In addition, electrocatalytic performance tests of chiral and racemic oxide nanoparticles confirm that the chiral catalyst exhibits superior catalytic activity and faster reaction kinetics, indicating that the electron spin polarization induced by the CISS effect effectively improves the efficiency of water electrolysis.

[0035] Figure 1 This is the Raman spectrum of the dextrorotatory / levorotatory / racemic (D / L / DL)-Co3O4 nanoparticles prepared in Example 1; wherein D-Co3O4 corresponds to dextrorotatory Co3O4 nanoparticles, L-Co3O4 corresponds to left-handed Co3O4 nanoparticles, and DL-Co3O4 corresponds to racemic Co3O4 nanoparticles.

[0036] Figure 2 This is the ultraviolet absorption spectrum of the D / L / DL-Co3O4 nanoparticles prepared in Example 1.

[0037] Figure 3 Circular dichroism spectra and chiral g-factor diagrams of the D / L / DL-Co3O4 nanoparticles prepared in Example 1; Figure (a) corresponds to the circular dichroism spectra (or circular dichroism diagram), and Figure (b) corresponds to the chiral g-factor diagram.

[0038] Figure 4 Transmission electron micrographs of D / L / DL-Co3O4 nanoparticles prepared in Example 1. Figure (a) corresponds to a transmission electron micrograph of D-Co3O4 nanoparticles, Figure (b) corresponds to a transmission electron micrograph of L-Co3O4 nanoparticles, and Figure (c) corresponds to a transmission electron micrograph of DL-Co3O4 nanoparticles.

[0039] Figure 5 D / L / DL-Co prepared in Example 2 2.4 Fe 0.6 Circular dichroism spectrum and chiral g-factor diagram of O4 nanoparticles; among them, Figure (a) corresponds to the circular dichroism spectrum (or circular dichroism diagram), and Figure (b) corresponds to the chiral g-factor diagram.

[0040] Figure 6 D / L / DL-Co prepared in Example 3 2.4 Ni 0.6Circular dichroism spectrum and chiral g-factor diagram of O4 nanoparticles; among them, Figure (a) corresponds to the circular dichroism spectrum (or circular dichroism diagram), and Figure (b) corresponds to the chiral g-factor diagram.

[0041] Figure 7 This is a linear sweep voltammogram of Example 4 using D / L / DL-Co3O4 nanoparticles as an anode catalyst for water electrolysis. “V verse RHE” represents the potential relative to the reversible hydrogen electrode.

[0042] Figure 8 This is the Tafel slope plot of Example 4 using D / L / DL-Co3O4 nanoparticles as anode catalyst for water electrolysis; Figure 9 This is the circular dichroism spectrum of D / L / DL-Co3O4-2 nanoparticles prepared in Comparative Example 1; wherein D-Co3O4-2 corresponds to the right-handed Co3O4 nanoparticles in Comparative Example 1, L-Co3O4-2 corresponds to the left-handed Co3O4 nanoparticles in Comparative Example 1, and DL-Co3O4-2 corresponds to the racemic Co3O4 nanoparticles in Comparative Example 1.

[0043] Figure 10 This is the linear sweep voltammogram of the D / L / DL-Co3O4-2 nanoparticles prepared in Comparative Example 1 as an anode catalyst for water electrolysis.

[0044] Example 1 37.83 mg of sodium borohydride was dissolved in 10 mL of deionized water to prepare solution ① (i.e., reducing agent solution), 121.16 mg of D / L / DL-cysteine ​​was dissolved in 10 mL of deionized water to prepare solution ② (i.e., chiral small molecule solution), 294.1 mg of sodium citrate was dissolved in 10 mL of deionized water to prepare solution ③ (i.e., complexing agent solution), and 129.84 mg of cobalt chloride was dissolved in 5 mL of deionized water to prepare solution ④ (i.e., metal salt solution). Solutions ①-④ were fully stirred to ensure that they dissolved to form a uniform, transparent solution. Subsequently, 50 mL of deionized water was added to the flask, and 10 mL of solution ①, 8 mL of solution ②, 8 mL of solution ③, and 4 mL of solution ④ were added in sequence under continuous stirring. Note that each solution should be stirred for 5 minutes before adding the next one to ensure that the solutions are fully mixed. When all four solutions were added, the solution instantly turned from transparent to brown-black, indicating that the chemical reaction had begun. The solution was stirred for 2 hours at 45°C, and gradually became a suspension. Finally, 10 times the volume of isopropanol was added to precipitate the nanoparticles. The nanoparticles were then centrifuged at 10,000 rpm for 20 minutes to obtain the precipitate, which was then dried in a vacuum oven at 45°C overnight to obtain chiral D / L-Co3O4 and racemic DL-Co3O4 nanoparticles (i.e., chiral oxide nanoparticles).

[0045] like Figure 1 As shown in the figure, the Raman spectra of D / L / DL-Co3O4 are similar, with the peak at 193 cm -1 , 520 cm -1 and 611 cm -1 The Raman peak at corresponds to the Co-O bond F 2g Vibration mode, 483 cm -1 The Raman peak at E g Vibration mode, 680 cm -1 The Raman peak at A 1g The vibration mode clearly shows that the prepared oxide is spinel structure Co3O4.

[0046] like Figure 2 As shown in the figure, the UV absorption spectrum of D / L / DL-Co3O4 has strong absorption peaks at 279 nm, 348 nm, and 440 nm, corresponding to Co 2+ To Co 3+ The electronic transitions of D / L / DL-Co3O4 indicate similar electronic structures within the D / L / DL-Co3O4.

[0047] like Figure 3 As shown in (a), the highly symmetrical circular dichroism spectra reveal that D-Co3O4, L-Co3O4, and DL-Co3O4 materials have right-handed, left-handed, and racemic chiral structures, respectively, and the obvious symmetrical peaks in the wavelength range of 400-700 nm indicate that the prepared cobalt trioxide has an intrinsic chiral structure. In addition, Figure 3 The chiral g factor of D / L-Co3O4 in (b) can reach 10 -2 This indicates once again that the intrinsic strong chirality inside the chiral oxide is one order of magnitude higher than that of most current chiral materials.

[0048] like Figure 4 As shown, transmission electron microscopy (TEM) analysis of the morphology and size of D / L / DL-Co₃O₄ reveals that both chiral and racemic Co₃O₄ are nanoparticles measuring 3-5 nm. This extremely small size gives the chiral oxides a large surface area when used as catalysts, facilitating efficient electrocatalysis. Furthermore, the lack of significant size differences among the different chiral oxides eliminates the possibility of size effects on catalysis.

[0049] Example 2 A method for preparing a chiral oxide comprises the following steps: Dissolve 37.83 mg of sodium borohydride in 10 mL of deionized water to prepare solution ①, 121.16 mg of D / L / DL-cysteine ​​in 10 mL of deionized water to prepare solution ②, 294.1 mg of sodium citrate in 10 mL of deionized water to prepare solution ③, and 103.87 mg of cobalt chloride and 32.44 mg of ferric chloride in 5 mL of deionized water to prepare solution ④. Subsequently, add 50 mL of deionized water to the flask and, while stirring continuously, add 10 mL of solution ①, 8 mL of solution ②, 8 mL of solution ③, and 4 mL of solution ④ in sequence. Upon completion of the additions, the solution instantly turns from transparent to brown-black. The solution was stirred for 2 hours at 25 ° C, and gradually turned into a suspension. Finally, 10 times the volume of isopropanol was added to precipitate the nanoparticles, and then the precipitate was centrifuged at 10000 rpm for 20 minutes. The precipitate was then placed in a vacuum oven at 45 ° C and dried overnight to obtain chiral D / L-Co 2.4 Fe 0.6 O4 and racemic DL-Co 2.4 Fe 0.6 O4 nanoparticles (i.e., chiral oxide nanoparticles).

[0050] like Figure 5 As shown in (a), similar to Co3O4 in Example 1, the D-Co after the introduction of Fe element 2.4 Fe 0.6 O4、L-Co 2.4 Fe 0.6 O4, and DL-Co 2.4 Fe 0.6 O4 also has right-handed, left-handed, and racemic chiral structures. Figure 5 (b) D / L-Co 2.4 Fe 0.6 The g factor of O4 material also reaches 10 -2 The magnitude of these ions also indicates their intrinsic strong chirality.

[0051] Example 3 A method for preparing a chiral oxide comprises the following steps: 37.83 mg of sodium borohydride was dissolved in 10 mL of deionized water to form solution ①, 121.16 mg of D / L / DL-cysteine ​​was dissolved in 10 mL of deionized water to form solution ②, 294.1 mg of sodium citrate was dissolved in 10 mL of deionized water to form solution ③, and 103.87 mg of cobalt chloride and 25.92 mg of nickel chloride were dissolved in 5 mL of deionized water to form solution ④. Subsequently, 50 mL of deionized water was added to the flask, and 10 mL of solution ①, 8 mL of solution ②, 8 mL of solution ③, and 4 mL of solution ④ were added in sequence under continuous stirring. After the addition was completed, the solution instantly turned from transparent to brown-black. Stirring was continued at 25°C for 2 hours, and the solution gradually became a suspension. Finally, 10 times the volume of isopropanol was added to precipitate the nanoparticles, followed by centrifugation at 10,000 rpm for 20 minutes to obtain the precipitate, which was then placed in a vacuum oven at 45°C and dried overnight to obtain chiral D / L-Co nanoparticles. 2.4 Ni 0.6 O4 and racemic DL-Co 2.4 Ni 0.6 O4 nanoparticles (i.e., chiral oxide nanoparticles).

[0052] like Figure 6 As shown, D-Co after the introduction of Ni element 2.4 Ni 0.6 O4、L-Co 2.4 Ni 0.6 O4, and DL-Co 2.4 Fe 0.6 O4 also has right-handed, left-handed, and racemic chiral structures, and D / L-Co 2.4 Ni 0.6 The g-factor of O4 is also at a high level, which shows that this synthesis method is universal and can successfully prepare a series of strong intrinsic chiral oxides.

[0053] Example 4 The chiral D / L-Co3O4 and racemic DL-Co3O4 powders prepared in Example 1 were used as anode catalysts for water electrolysis to test their electrocatalytic performance. 5 mg of the powder was dissolved in 1 mL of a mixture of deionized water, isopropanol, and Nafion (perfluorosulfonic acid polymer) membrane solution (the volumes of deionized water, isopropanol, and Nafion membrane solution were 775 μL, 200 μL, and 25 μL, respectively). The mixture was ultrasonicated for 2 hours to form a slightly viscous catalyst slurry. 10 μL of the catalyst slurry was then evenly applied to a glassy carbon electrode. After the electrode was completely dry, the electrochemical performance was tested. During the tests, a platinum electrode was used as the counter electrode, a mercury / mercuric oxide electrode was used as the working electrode, and a 1 mol / L potassium hydroxide solution was used as the electrolyte.

[0054] like Figure 7 As shown in Figure 2, the current densities of D-Co3O4 and L-Co3O4 at 1.7 V are 21.93 mA cm -2 and 21.14 mA cm -2 ; while the corresponding current density of DL-Co3O4 at 1.7 V was only 14.10 mA cm -2 It can be seen that the catalytic activity of chiral Co3O4 is better than that of racemic Co3O4. This indicates that the chiral catalyst induces electron spin polarization through the CISS effect, thereby promoting the electrolysis of water and accelerating the generation of triplet oxygen.

[0055] like Figure 8 As shown in Figure 3, the Tafel slopes of D-Co3O4 and L-Co3O4 are both smaller than that of DL-Co3O4, indicating that the spin polarization induced by the chiral structure promotes the rapid transfer of electrons during the reaction, thereby accelerating the electrochemical reaction kinetics.

[0056] Comparative Example 1 The only difference between Comparative Example 1 and Example 1 is that in Comparative Example 1, the chiral small molecule used in the preparation process of Example 1 is replaced by an equal amount of tartaric acid. The product prepared in Comparative Example 1 is named D / L / DL-Co3O4-2.

[0057] like Figure 9 As shown, the circular dichroism spectrum of the product prepared in Comparative Example 1 exhibits symmetrical chiral signals only at wavelengths between 200 and 350 nm, indicating that the product possesses only ligand chirality, rather than the intrinsic chirality of tris(III) tetraoxide. Furthermore, the intensity of the chiral signal is weaker than that of the chiral oxide obtained in Example 1.

[0058] The product prepared in Comparative Example 1 was used as an anode catalyst to test its water electrolysis performance, and the specific testing process was the same as that in Example 4.

[0059] The results are as follows Figure 10 As shown in Figure 2, the current densities corresponding to D-Co3O4-2, L-Co3O4-2, and DL-Co3O4-2 at 1.7 V are 9.57 mA cm -2 , 12.20 mA cm -2 , and 10.33 mA cm -2 It can be seen that the performance of the products prepared after replacing the chiral small molecules is worse than that of the chiral oxide in Example 1; moreover, the performance of the chiral products and the racemic products also show randomness.

Claims

1. A chiral oxide, characterized in that Its chemical formula is Co 3-x M x O4, wherein M is a transition metal element and a non-precious metal element, and x is greater than or equal to 0 and less than 3.

2. The chiral oxide according to claim 1, characterized in that The M is selected from at least one of Co, Fe, and Ni.

3. The chiral oxide according to claim 1, characterized in that The chiral oxide is nanometer-scale particles.

4. The chiral oxide according to claim 1, characterized in that The size of the chiral oxide is 1-10 nm.

5. The chiral oxide according to any one of claims 1 to 4, characterized in that The chiral g factor of the chiral oxide is up to 10 -2 Magnitude.

6. The chiral oxide according to claim 1, characterized in that The chiral oxide is selected from D / L-Co3O4, racemic DL-Co3O4, D / L-Co 2.4 Fe 0.6 O4, racemic DL-Co 2.4 Fe 0.6 O4、D / L-Co 2.4 Ni 0.6 O4, racemic DL-Co 2.4 Ni 0.6 At least one of O4.

7. The method for preparing a chiral oxide according to any one of claims 1 to 6, characterized in that: The following steps are involved: (1) Prepare reducing agent solution, chiral small molecule solution, complexing agent solution and metal salt solution respectively and set aside; (2) adding water to the container, and then adding the reducing agent solution, chiral small molecule solution, complexing agent solution and metal salt solution, stirring and mixing, centrifuging to obtain a solid, and drying to obtain the chiral oxide; The chiral small molecule in the chiral small molecule solution is selected from at least one of cysteine, threonine and penicillamine.

8. The preparation method according to claim 7, characterized in that The reducing agent in the reducing agent solution is selected from at least one of sodium borohydride, sodium hydroxide, and potassium hydroxide; and / or the complexing agent in the complexing agent solution is selected from sodium citrate or sodium citrate hydrate; and / or the metal salt in the metal salt solution is selected from at least one of transition metal chlorides, transition metal nitrates, and transition metal sulfates.

9. The preparation method according to claim 7, characterized in that The concentration of the reducing agent solution is 0.05-0.3 mol / L; and / or, the concentration of the chiral small molecule solution is 0.01-0.6 mol / L; and / or, the concentration of the complexing agent solution is preferably 0.05-0.6 mol / L; and / or, the concentration of the metal salt solution is preferably 0.05-0.6 mol / L; and / or, in step (2), the volume ratio of the reducing agent solution, the chiral small molecule solution, the complexing agent solution and the metal salt solution is 1-30: (1-18): (1-12): (0.5-12).

10. Use of the chiral oxide according to any one of claims 1 to 6 in the field of electrocatalysis.

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