A multi-component cathode for photoelectrochemical hydrogen evolution and its preparation method

Abstract

The present invention belongs to the technical field of electrochemical energy conversion, and particularly relates to a multi-component cathode for photoelectrochemical hydrogen evolution and a preparation method thereof. The preparation method includes the following steps: mixing a metal salt, ammonium fluoride and an alkali to obtain a mixed solution; wherein the metal salt includes a cobalt salt and a nickel salt; adding a conductive substrate into the mixed solution and carrying out a microwave-assisted reaction to obtain a reaction product; annealing the reaction product under an air atmosphere to obtain the multi-component cathode. The multi-component cathode includes a conductive substrate, and Co3O4 and Ni(OH)2 are loaded on the conductive substrate; Co3O4 and Ni(OH)2 are in close contact with each other and have a matching energy band structure. After being irradiated by light, photo-generated electrons can easily form a circuit between the two components, showing a higher electron-hole separation efficiency relative to a single component, greatly improving the photoelectric conversion efficiency and promoting the hydrogen evolution reaction.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrochemical energy conversion, and particularly relates to a multi-component cathode for photoelectrochemical hydrogen evolution and a preparation method thereof. Background Art

[0002] In order to solve the problems of environmental pollution and energy shortage, in the past few decades, extensive research has been carried out on renewable energy. As a clean and efficient renewable energy, hydrogen has the characteristics of high combustion efficiency and no pollution of products, and is considered to be one of the best alternatives to fossil energy.

[0003] Traditional hydrogen production technologies mainly include fossil fuel hydrogen production (such as methane reforming, natural gas cracking, etc.), biomass raw material hydrogen production (such as thermochemical decomposition, etc.). These hydrogen production processes often generate a large amount of by-products such as carbon dioxide, directly leading to the greenhouse effect and being unfavorable for solving environmental problems. Photocatalytic hydrogen production is a clean hydrogen production method based on the reduction of H + by photo-generated electrons to produce hydrogen, but its development and application are still restricted by its low solar energy conversion efficiency. Compared with photocatalytic hydrogen production, photoelectrochemical hydrogen production can promote the migration of photo-generated electrons by applying an external electric field, thus greatly improving the solar energy conversion efficiency and the hydrogen production rate, and is one of the most important routes for sustainable energy hydrogen production at present.

[0004] So far, composite catalysts for photoelectrochemical catalysis have been widely studied. These composite catalysts can generate photo-generated electrons and holes in the conduction band and valence band respectively under visible light irradiation, and transfer to form a circuit, reducing the recombination of photo-generated electrons and holes and improving the catalytic hydrogen evolution efficiency. However, these composite catalysts still have problems such as a relatively narrow intrinsic band gap and poor band matching between each other, resulting in slow transfer and easy recombination of photo-generated electrons, thus leading to low energy conversion efficiency and further restricting the development, application and popularization of photoelectrochemical hydrogen production. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. For this purpose, the present invention provides a multi-component cathode for photoelectrochemical hydrogen evolution and a preparation method thereof. The preparation method adopts a two-step method of microwave-assisted reaction and annealing treatment, and can quickly prepare a Co3O4 / Ni(OH)2 multi-component cathode supported on a self-supporting conductive substrate. There is a matching energy band structure between Co3O4 and Ni(OH)2 in the cathode, and the two components are in close contact, endowing the electrode with a low hydrogen evolution overpotential and good overall electrode stability.

[0006] To overcome the above technical problems, the first aspect of the present invention provides a preparation method of a multi-component cathode.

[0007] Specifically, a method for preparing a multi-component cathode includes the following steps:

[0008] (1) Mix a metal salt, ammonium fluoride, and an alkali to obtain a mixed solution; the metal salt includes a cobalt salt and a nickel salt;

[0009] (2) Add a conductive substrate to the mixed solution and perform a microwave-assisted reaction to obtain a reaction product;

[0010] (3) Anneal the reaction product under an air atmosphere condition to obtain the multi-component cathode.

[0011] The multi-component cathode of the present invention uses a cobalt salt, a nickel salt, ammonium fluoride, and an alkali as raw materials, wherein: the cobalt salt and the nickel salt are used to provide a cobalt source and a nickel source, and the alkali is used to adjust the pH value of the mixed solution to be in an alkaline condition and act together with ammonium fluoride to promote the formation of a flaky structure of the product obtained by the subsequent microwave-assisted reaction; under the microwave-assisted reaction and annealing treatment at high temperature and high pressure, each raw material undergoes a recrystallization reaction to obtain multi-component products Co3O4 and Ni(OH)2, wherein: the conduction band of Co3O4 is located at -0.49 eV and the valence band is located at 1.45 eV; the conduction band of Ni(OH)2 is located at -0.14 eV and the valence band is located at 3.08 eV. Due to the matching energy band structure between Co3O4 and Ni(OH)2, and at the same time, the two components are in close contact during the reaction, after being irradiated by light, photo-generated electrons can quickly transfer from Co3O4 to Ni(OH)2, and holes transfer from Ni(OH)2 to Co3O4 to form a circuit, showing a higher electron-hole separation efficiency compared to single components, effectively improving the photoelectric conversion efficiency. It can exhibit an obvious photocurrent response in an alkaline electrolyte, have a low hydrogen evolution overpotential, and good overall electrode stability, and is suitable for photoelectrochemical water splitting reactions under high current density conditions.

[0012] As a further improvement of the above solution, the cobalt salt is selected from at least one of cobalt chloride, cobalt nitrate, and cobalt sulfate; the nickel salt is selected from at least one of nickel chloride, nickel nitrate, and nickel sulfate. Selecting soluble cobalt salts and nickel salts mainly serves as precursors of platinum and nickel to provide a cobalt source and a nickel source.

[0013] As a further improvement of the above solution, the concentration of the metal salt is 10 - 100 mmol / L, and the molar ratio of the cobalt salt to the nickel salt is (0.2 - 5):1.

[0014] As a further improvement of the above solution, the concentration of ammonium fluoride is 10 - 500 mmol / L. The concentration of ammonium fluoride has a certain influence on the morphology of the reaction. Adding a certain amount of ammonium fluoride under alkaline conditions is more conducive to the formation of flaky Co3O4 and Ni(OH)2.

[0015] As a further improvement of the above solution, the base is selected from urea and / or ammonia water, and the concentration of the base is 10 - 300 mmol / L. The base is mainly used to adjust the pH value of the mixed solution to ensure the alkaline state of the reaction solution.

[0016] As a further improvement of the above solution, the conductive substrate is selected from any one of a metal substrate, a carbon substrate, and a glass substrate; the metal substrate is selected from nickel foam or copper foam; the carbon substrate is selected from carbon paper or graphite flakes; the glass substrate is selected from ITO conductive glass or FTO conductive glass. The conductive substrate mainly serves as a carrier for the cathode material, is a self-supporting substrate, and can support the reaction products Co3O4 and Ni(OH)2.

[0017] As a further improvement of the above solution, before use, the conductive substrate further includes steps of degreasing and drying to prevent the introduction of other impurity components.

[0018] As a further improvement of the above solution, in step (2), the temperature of the microwave-assisted reaction is 120 - 220 °C, and the time is 0.5 - 2 hours. Using microwave-assisted reaction not only helps to accelerate the reaction rate, but also is more conducive to the close contact between Co3O4 and Ni(OH)2 and the formation of a matching energy band between the two components.

[0019] As a further improvement of the above solution, in step (3), the temperature of the annealing treatment is 250 - 350 °C, and the time is 0.5 - 1.5 hours. The annealing treatment can remove the crystal water in the microwave-assisted reaction product and further promote the close contact between Co3O4 and Ni(OH)2.

[0020] The second aspect of the present invention provides a multi-component cathode.

[0021] Specifically, a multi-component cathode, characterized in that the multi-component cathode is prepared by using the preparation method of the multi-component cathode of the present invention, the multi-component cathode includes a conductive substrate, and Co3O4 and Ni(OH)2 are loaded on the conductive substrate, and Co3O4 and Ni(OH)2 are in close contact with each other and have a matching energy band structure.

[0022] The multi-component cathode of the present invention includes a conductive substrate, Co3O4 and Ni(OH)2. There is a matching energy band structure between Co3O4 and Ni(OH)2, and the two components are in close contact. When irradiated with light, photo-generated electrons are easily formed into a circuit between the two, which can effectively reduce the recombination rate of photo-generated electrons and holes, thereby improving the light conversion efficiency and promoting the hydrogen evolution reaction.

[0023] The third aspect of the present invention provides an application of a multi-component cathode.

[0024] Specifically, the application of the multi-component cathode of the present invention in photoelectrochemical hydrogen evolution, chlor-alkali industry or hydrogen-oxygen fuel cells.

[0025] The above technical solutions of the present invention have at least the following technical effects or advantages compared with the prior art:

[0026] (1) The multi-component cathode of the present invention is prepared by a two-step method of microwave-assisted reaction and annealing treatment to prepare the multi-component cathode, which is faster and more efficient than the preparation of traditional hydrothermal and high-temperature annealing methods. At the same time, the Co3O4 and Ni(OH)2 in the prepared multi-component cathode have a matched energy band structure, and the two components are in close contact during the reaction. After being irradiated by light, photo-generated electrons are easy to form a circuit between the two, showing a higher electron-hole separation efficiency than that of single components, greatly improving the photoelectric conversion efficiency and promoting the hydrogen evolution reaction. In addition, it can show an obvious photocurrent response in alkaline electrolyte, and has a low hydrogen evolution overpotential and good overall electrode stability, and is suitable for photoelectrolytic water reaction under high current density conditions.

[0027] (2) The multi-component cathode prepared by the present invention not only has good electrocatalytic hydrogen evolution performance, but also has excellent photoelectrocatalytic hydrogen evolution performance under light illumination. When the current density reaches -100 mA cm -2 , the overpotential under dark condition is 256 - 268 mV, and the overpotential under light illumination is only 229 - 232 mV. Description of the Drawings

[0028] Figure 1 Scanning electron microscope image of the multi-component cathode sample prepared in Example 1;

[0029] Figure 2 High-resolution transmission electron microscope image of the multi-component cathode sample prepared in Example 1;

[0030] Figure 3 X-ray diffraction pattern of the multi-component cathode sample prepared in Example 1;

[0031] Figure 4 Electrochemical polarization curve of the multi-component cathode samples prepared in Examples 1 - 3 in 1 M KOH solution under light illumination and dark conditions;

[0032] Figure 5 Chronocurrent curve of the multi-component cathode samples prepared in Examples 1 - 3 in 1 M KOH solution under light illumination and dark conditions;

[0033] Figure 6 Photoluminescence spectrum of the multi-component cathodes prepared in Example 1 and Comparative Examples 1 - 2;

[0034] Figure 7Schematic diagram of the energy band matching of the sample prepared in Example 1. Detailed implementation mode

[0035] The present invention will be specifically described below in conjunction with examples to facilitate the understanding of the present invention by those skilled in the art. It is necessary to specifically point out here that the examples are only used to further illustrate the present invention and should not be construed as limiting the protection scope of the present invention. Those skilled in the art, based on the above-mentioned invention content, make non-essential improvements and adjustments to the present invention, which should still fall within the protection scope of the present invention. At the same time, for the raw materials not specifically described below, they are all commercially available products; the process steps or preparation methods not specifically mentioned are all process steps or preparation methods known to those skilled in the art.

[0036] Example 1

[0037] A preparation method of a multi-component cathode includes the following steps:

[0038] (1) Select a foam nickel with a size of 2×4 cm as the conductive substrate. First, immerse it in dilute hydrochloric acid to remove the surface oxides, then wash it with ultrapure water, and place it in a vacuum oven for drying and standby;

[0039] (2) Prepare a mixed solution, wherein: the concentration of cobalt nitrate hexahydrate is 30 mmol / L, the concentration of nickel nitrate hexahydrate is 30 mmol / L, the concentration of ammonium fluoride is 100 mmol / L, and the concentration of urea is 200 mmol / L; then dissolve the mixed solution in 30 mL of ultrapure water and ultrasonicate for 30 minutes to fully dissolve it;

[0040] (3) Transfer the mixed solution prepared in step (2) to a polytetrafluoroethylene inner liner, add the foam nickel pretreated in step (1), encapsulate it in a reaction kettle, carry out a microwave-assisted reaction at a temperature of 160 °C for 1 hour, then cool the reaction kettle to room temperature, take out the reaction product, wash it repeatedly with ultrapure water and dry it to obtain a reactant;

[0041] (4) Place the reactant prepared in step (3) in a muffle furnace at 300 °C, under an air atmosphere condition, carry out an annealing treatment for 1 hour, and after cooling, obtain the Co3O4 / Ni(OH)2 multi-component cathode supported on foam nickel of this example.

[0042] Example 2

[0043] A preparation method of a multi-component cathode includes the following steps:

[0044] (1) Select an ITO conductive glass with a size of 2×4 cm as the conductive substrate. First, immerse it in dilute hydrochloric acid to remove the surface oxides, then wash it with ultrapure water, and place it in a vacuum oven for drying and standby;

[0045] (2) Prepare a mixed solution, where: the concentration of cobalt nitrate hexahydrate is 15 mmol / L, the concentration of nickel nitrate hexahydrate is 45 mmol / L, the concentration of ammonium fluoride is 100 mmol / L, and the concentration of urea is 200 mmol / L; then dissolve the mixed solution in 30 mL of ultrapure water and ultrasonicate for 30 minutes to fully dissolve it;

[0046] (3) Transfer the mixed solution prepared in step (2) to a polytetrafluoroethylene inner liner, add the ITO conductive glass pretreated in step (1), encapsulate it in a reaction kettle, carry out microwave-assisted reaction at 140 °C for 0.5 hour, then cool the reaction kettle to room temperature, take out the reaction product, wash it repeatedly with ultrapure water and dry it to obtain the reactant;

[0047] (4) Place the reactant prepared in step (3) in a muffle furnace at 300 °C, and carry out annealing treatment for 1 hour under an air atmosphere condition. After cooling, obtain the Co3O4 / Ni(OH)2 multi-component cathode supported on the ITO conductive glass of this example.

[0048] Example 3

[0049] A preparation method of a multi-component cathode, comprising the following steps:

[0050] (1) Select a 2×4 cm-sized nickel foam as the conductive substrate, first immerse it in dilute hydrochloric acid to remove the surface oxides, then wash it with ultrapure water, and place it in a vacuum oven for drying for standby;

[0051] (2) Prepare a mixed solution, where: the concentration of cobalt chloride hexahydrate is 40 mmol / L, the concentration of nickel chloride hexahydrate is 20 mmol / L, the concentration of ammonium fluoride is 200 mmol / L, and the concentration of urea is 50 mmol / L; then dissolve the mixed solution in 30 mL of ultrapure water and ultrasonicate for 30 minutes to fully dissolve it;

[0052] (3) Transfer the mixed solution prepared in step (2) to a polytetrafluoroethylene inner liner, add the nickel foam pretreated in step (1), encapsulate it in a reaction kettle, carry out microwave-assisted reaction at 180 °C for 0.5 hour, then cool the reaction kettle to room temperature, take out the reaction product, wash it repeatedly with ultrapure water and dry it to obtain the reactant;

[0053] (4) Place the reactant prepared in step (3) in a muffle furnace at 300 °C, and carry out annealing treatment for 1 hour under an air atmosphere condition. After cooling, obtain the Co3O4 / Ni(OH)2 multi-component cathode supported on the nickel foam of this example.

[0054] Comparative Example 1

[0055] A preparation method of a single-component cathode, comprising the following steps:

[0056] (1) Select nickel foam with a size of 2×4 cm as the conductive substrate. First, immerse it in dilute hydrochloric acid to remove the surface oxides, then wash it with ultrapure water, and place it in a vacuum oven for drying for later use;

[0057] (2) Prepare a mixed solution, wherein: the concentration of cobalt nitrate hexahydrate is 35 mmol / L, the concentration of ammonium fluoride is 100 mmol / L, and the concentration of urea is 200 mmol / L; then dissolve the mixed solution in 30 mL of ultrapure water and ultrasonicate for 30 minutes to fully dissolve it;

[0058] (3) Transfer the mixed solution prepared in step (2) to a polytetrafluoroethylene inner liner, add the nickel foam pretreated in step (1), encapsulate it in a reaction kettle, carry out a microwave-assisted reaction at a temperature of 160 °C for 1 hour, then cool the reaction kettle to room temperature, take out the reaction product, wash it repeatedly with ultrapure water and dry it to obtain the reactant;

[0059] (4) Place the reactant prepared in step (3) in a muffle furnace at 300 °C, and carry out annealing treatment for 1 hour under an air atmosphere condition. After cooling, obtain the single-component cathode of Co3O4 supported on nickel foam of this comparative example.

[0060] The difference between Comparative Example 1 and Example 1 is only that the mixed solution does not contain nickel nitrate.

[0061] Comparative Example 2

[0062] A preparation method of a single-component cathode, comprising the following steps:

[0063] (1) Select nickel foam with a size of 2×4 cm as the conductive substrate. First, immerse it in dilute hydrochloric acid to remove the surface oxides, then wash it with ultrapure water, and place it in a vacuum oven for drying for later use;

[0064] (2) Prepare a mixed solution, wherein: the concentration of nickel nitrate hexahydrate is 55 mmol / L, the concentration of ammonium fluoride is 100 mmol / L, and the concentration of urea is 200 mmol / L; then dissolve the mixed solution in 30 mL of ultrapure water and ultrasonicate for 30 minutes to fully dissolve it;

[0065] (3) Transfer the mixed solution prepared in step (2) to a polytetrafluoroethylene inner liner, add the nickel foam pretreated in step (1), encapsulate it in a reaction kettle, carry out a microwave-assisted reaction at a temperature of 160 °C for 1 hour, then cool the reaction kettle to room temperature, take out the reaction product, wash it repeatedly with ultrapure water and dry it to obtain the reactant;

[0066] (4) The reactants obtained in step (3) were placed in a muffle furnace at 300 °C and annealed for 1 hour under an air atmosphere. After cooling, the Ni(OH)2 single-component cathode supported on nickel foam of this comparative example was obtained.

[0067] The difference between Comparative Example 2 and Example 1 is only that the mixed solution does not contain cobalt nitrate.

[0068] Performance test

[0069] 1. Morphology analysis

[0070] Figure 1 It is the scanning electron microscope image of the multi-component cathode sample prepared in Example 1. It can be seen that the cathode surface presents an obvious two-dimensional sheet structure. Figure 2 It is the high-resolution transmission electron microscope image of the multi-component cathode sample prepared in Example 1. The sheet structure of the sample can also be seen, and the lattice fringes can be clearly seen. After measurement, the lattice plane spacings are 0.46 nm and 0.29 nm respectively, corresponding to the (001) plane of Ni(OH)2 and the (220) plane of Co3O4. The two components are in close contact, which is beneficial to the transfer of photo-generated electrons and holes and reduces the probability of their recombination.

[0071] 2. Composition analysis

[0072] Figure 3 It is the X-ray diffraction pattern of the multi-component cathode sample prepared in Example 1. Figure 3 In it, the abscissa 2-Theta represents the 2θ angle, and the ordinate Intensity represents the intensity of the diffraction peak. Among them, 44.5°, 51.8° and 76.4° correspond to the (111), (200) and (220) crystal planes of the nickel foam conductive substrate respectively; the characteristic peaks at 19.0°, 31.3°, 36.8°, 59.3° and 65.2° correspond to the (111), (220), (311), (511) and (440) crystal planes of Co3O4; the characteristic peaks at 19.3°, 33.1°, 38.5°, 59.0° and 60.2° correspond to the (001), (100), (101), (110) and (003) crystal planes of Ni(OH)2.

[0073] 3. Photoelectrocatalytic hydrogen evolution performance

[0074] Figure 4 It is the electrochemical polarization curve of the multi-component cathode samples prepared in Examples 1-3 in 1 M KOH solution under illuminated and non-illuminated conditions. Figure 4 In it, the abscissa Potential represents the voltage, and the ordinate Current density represents the current density. From Figure 4It can be seen that there are obvious differences in the catalytic performance of the hydrogen evolution cathode under dark and light illumination conditions. When the current density reaches -100 mA cm -2 ², the overpotential under dark conditions is 256 - 268 mV, while that under light illumination conditions is only 229 - 232 mV, as shown in Table 1 specifically.

[0075] Table 1: Comparison table of photo - electro - catalytic hydrogen evolution performance of multi - component cathode samples prepared in Examples 1 - 3

[0076]

[0077]

[0078] As can be seen from Table 1, the multi - component electrodes prepared in Examples 1 - 3 of the present invention not only have good electro - catalytic hydrogen evolution performance, but also have excellent photo - electro - catalytic hydrogen evolution performance under light illumination conditions.

[0079] Figure 5 Fig. is the chronoamperometry curves of the multi - component cathode samples prepared in Examples 1 - 3 in 1 M KOH solution under light illumination and dark conditions. Figure 5 In which, the abscissa Time represents time, and the ordinate Current density represents current density. From Figure 5 it can be seen that maintaining a constant potential of -0.2 V vs. RHE, with a cycle of 50 seconds, alternately illuminating and stopping illumination, it can be seen that when illuminated, the response current increases significantly compared with that in the dark, indicating that obvious photocurrent is generated on the electrode under light illumination conditions, and it has excellent photo - electro - catalytic hydrogen evolution performance.

[0080] Figure 6 Fig. is the photoluminescence spectrum of the multi - component cathodes prepared in Example 1 and Comparative Examples 1 - 2. Figure 6 In which, the abscissa Wavelength represents wavelength, and the ordinate PL intensity represents photo - excitation light intensity. From Figure 6 it can be seen that the emission peak near 600 nm of the electrode is generated by the recombination of photo - generated electrons and holes. Compared with the single - component electrodes Co3O4 and Ni(OH)2 prepared in Comparative Examples 1 - 2, the fluorescence emission peak of the multi - component electrode prepared in Example 1 is the weakest, indicating that after the combination of Co3O4 and Ni(OH)2, the separation efficiency of photo - generated electrons and holes is significantly improved, which is more conducive to the photo - electro - catalytic hydrogen evolution reaction.

[0081] 4. Energy band structure

[0082] Figure 7 Fig. is the schematic diagram of energy band matching of the multi - component cathode sample prepared in Example 1. From Figure 7It can be seen that the conduction band of Co3O4 in the sample is located at -0.49 eV, the valence band is located at 1.45 eV, the conduction band of Ni(OH)2 is located at -0.14 eV, and the valence band is located at 3.08 eV. Under light illumination conditions, photo-generated electrons are likely to form a circuit between the two, effectively reducing the recombination rate of photo-generated electrons and holes, thereby improving the light conversion efficiency and promoting the hydrogen evolution reaction.

[0083] In addition, the multi-component cathodes prepared in Examples 2-3 were subjected to the same tests as in Example 1, and the test results were similar to those in Example 1, all having good photoelectrochemical hydrogen evolution catalytic performance.

[0084] For those of ordinary skill in the art to which the present invention pertains, several simple deductions or substitutions can be made without departing from the inventive concept of the present invention, without the need for creative labor. Therefore, simple improvements made by those skilled in the art based on the disclosure of the present invention should fall within the protection scope of the present invention. The above embodiments are the preferred embodiments of the present invention, and all processes similar to the present invention and equivalent changes made thereto should fall within the protection scope of the present invention.

Claims

1. A preparation method of a multi-component cathode, characterized in that, Comprising the following steps: (1) Mix a metal salt, ammonium fluoride and an alkali to obtain a mixed solution; the metal salt is a cobalt salt and a nickel salt, the cobalt salt is selected from at least one of cobalt chloride, cobalt nitrate, and cobalt sulfate, and the nickel salt is selected from at least one of nickel chloride, nickel nitrate, and nickel sulfate; (2) Add a conductive substrate to the mixed solution and carry out a microwave-assisted reaction to obtain a reaction product; the temperature of the microwave-assisted reaction is 120-220 °C and the time is 0.5-2 hours; (3) Anneal the reaction product under an air atmosphere to obtain the multi-component cathode; the temperature of the annealing treatment is 250-350 °C and the time is 0.5-1.5 hours.

2. The method for preparing a multi-component cathode according to claim 1, characterized in that, The concentration of the metal salt is 10-100 mmol / L, and the molar ratio of the cobalt salt to the nickel salt is (0.2-5):

1.

3. The method for preparing a multi-component cathode according to claim 1, wherein, The concentration of the ammonium fluoride is 10-500 mmol / L.

4. The method for preparing a multi-component cathode according to claim 1, wherein, The alkali is selected from urea and / or ammonia water, and the concentration of the alkali is 10-300 mmol / L.

5. The preparation method of the multi-component cathode according to claim 1, characterized in that, The conductive substrate is selected from any one of a metal substrate, a carbon substrate, and a glass substrate; the metal substrate is selected from nickel foam or copper foam; the carbon substrate is selected from carbon paper or graphite flakes; the glass substrate is selected from ITO conductive glass or FTO conductive glass.

6. A multi-component cathode, characterized in that, The multi-component cathode is prepared by the preparation method of the multi-component cathode according to any one of claims 1 to 5. The multi-component cathode includes a conductive substrate, and Co3O4 and Ni(OH)2 are loaded on the conductive substrate; Co3O4 and Ni(OH)2 are in close contact with each other and have a matching energy band structure, and the surface of the cathode has a two-dimensional flaky structure.

7. Application of the multi-component cathode according to claim 6 in photoelectrochemical hydrogen evolution.

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