Method for improving electro-catalytic hydrogen evolution activity by using moving electrode

Abstract

The invention belongs to the field of water electrolysis hydrogen production, relates to a method for improving electro-catalysis hydrogen evolution activity by using a moving electrode, and aims to solve the problems that when water electrolysis hydrogen production adopts a constant electrode condition for electrolysis, the electrode stability is relatively low, the hydrogen production rate is relatively poor, and produced hydrogen bubbles are easy to adhere to the electrode, so that efficient hydrogen production is severely hindered. According to the method, a two-dimensional material is used as a working electrode, H2SO4 is used as an electrolyte, a carbon rod is used as a counter electrode, and Hg / Hg2SO4 is used as a reference electrode; then, after the linear motor is connected with the working electrode, the working electrode is controlled to be immersed in and moved out of the electrolyte up and down, and the electrocatalytic hydrogen evolution performance of the two-dimensional material is remarkably improved. According to the method, on the premise that the two-dimensional material is not modified, the working electrode can be controlled by the linear motor to be vertically immersed in and moved out of the electrolyte, the hydrogen generation rate of the two-dimensional material can be remarkably increased (the hydrogen generation rate can reach 13.3 mu Lmin <-1 > cm < 2 >), and the method is simple and efficient and has a relatively strong industrial application prospect.

Description

Technical Field

[0001] The invention belongs to the field of hydrogen production by electrolysis of water and relates to a method for improving the activity of electrocatalytic hydrogen evolution by using a moving electrode. Background Art

[0002] Hydrogen energy has a high energy density, and its combustion product is water, making it an important substitute for fossil fuels. However, the current production of hydrogen mainly relies on the preparation of fossil fuels such as natural gas. The preparation of this gray hydrogen does not meet everyone's pursuit of green energy. The development of green hydrogen production methods is crucial for energy development. Water electrolysis hydrogen production technology can use renewable energy to produce hydrogen. It is a potential green hydrogen production method, and the hydrogen production process has almost zero carbon emissions. With the increasing demand for renewable energy, the development of an efficient water electrolysis system is crucial for the utilization of hydrogen energy. Current research on the understanding and design of catalysts, electrolytes and electrolyzers has achieved relatively significant results. For example, patent CN115784327A discloses the preparation and application of medium-entropy sulfide materials with MOF structures. The medium-entropy sulfide materials are prepared by a solvothermal method. The material has the advantages of good stability, high repeatability, and excellent catalytic performance. However, the current electrolysis of water to produce hydrogen is usually carried out under constant electrode conditions. Under constant electrode conditions, the electrode is fixed and the reaction is carried out under constant voltage conditions without generating a charging current. The bubbles generated by the reaction will be adsorbed on the electrode surface, resulting in low catalytic reaction activity and poor hydrogen production rate. There are still some challenges in its widespread application. Therefore, the development of a new, reliable, and highly active electrochemical hydrogen evolution technology is crucial to solving the problem of low hydrogen production rate in traditional electrocatalytic water electrolysis. Summary of the invention

[0003] In view of the technical problems that the existing electrolysis of water to produce hydrogen using a constant electrode for electrolysis, such as low electrode stability, poor hydrogen production rate, and the produced hydrogen bubbles easily adhering to the electrode, thus seriously hindering the efficient production of hydrogen, the present invention proposes a method for improving the activity of electrocatalytic hydrogen evolution using a moving electrode. By introducing a moving electrode device, the electrode is periodically moved to change the contact between the electrode and the electrolyte, regulate the electrode interface, and change the electrochemical behavior of the electrode catalysis. The introduction of the moving electrode can achieve a different degree of increase in the amount of charge input into the electrolytic cell compared to the constant electrode condition, thereby achieving an increase in the hydrogen generation rate. The method of the present invention is simple and easy to implement, and the introduction of the moving electrode can significantly increase the hydrogen generation rate.

[0004] In order to achieve the above object, the technical solution of the present invention is achieved as follows: A method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials by using a moving electrode, wherein the two-dimensional material is used as a working electrode, H2SO4 is used as an electrolyte, a carbon rod is used as a counter electrode, and Hg / Hg2SO4 is used as a reference electrode; a linear motor is then connected to the working electrode to control the working electrode to be immersed in and removed from the electrolyte, thereby improving the electrocatalytic hydrogen evolution performance of the two-dimensional material.

[0005] The two-dimensional material is molybdenum disulfide, molybdenum carbide or metal-doped molybdenum disulfide.

[0006] The moving electrode utilizes a linear motor to control the up and down movement of the working electrode to form different modes.

[0007] The metal in the metal-doped molybdenum disulfide is Pt, Au or Pd.

[0008] The concentration of the electrolyte is 0.1 mM to 1 M. Preferably, the concentration of the electrolyte is 0.5 M.

[0009] The working unit of the two-dimensional material is -0.05 V ~ -0.2 V vs RHE.

[0010] The speed of the up and down immersion and removal is 5 mm / s to 200 mm / s. Preferably, the speed of the up and down immersion and removal is 90 mm / s.

[0011] The frequency of the up and down immersion and removal is 0.1 s to 5 s. Preferably, the frequency of the up and down immersion and removal is 1 s.

[0012] The present invention introduces a moving electrode to make the working electrode move up and down, and studies the electrocatalytic hydrogen evolution performance of the two-dimensional material under different working voltages, lifting speeds and lifting frequencies. By introducing the moving electrode, the electrocatalytic hydrogen evolution rate of the two-dimensional material is significantly improved.

[0013] The present invention has the following beneficial effects: (1) The present invention utilizes a moving electrode method, that is, a linear motor is connected to the working electrode to control the working electrode to immerse and move out of the electrolyte, which can significantly improve the electrocatalytic hydrogen evolution performance of the two-dimensional material. The method requires simple equipment and only requires an electrochemical workstation and a linear motor. Both the electrochemical workstation and the linear motor are existing products and can be purchased on the market.

[0014] (2) The mechanism of the present invention using a moving electrode to improve the activity of electrocatalytic hydrogen evolution is that the present invention introduces a moving electrode into the electrolysis system, which can charge the double electric layer on the electrode surface each time the electrode enters the electrolyte liquid surface, and the charging current can be used for hydrogen evolution reaction, thereby increasing the rate of hydrogen evolution reaction; in addition, the moving electrode can also accelerate the dissipation of bubbles on the electrode, which is beneficial to mass transfer. This solves the technical problems of low electrode stability, poor hydrogen production rate, and easy adhesion of hydrogen bubbles to the electrode in constant voltage or constant current electrolysis methods, thereby seriously hindering the efficient production of hydrogen.

[0015] (3) The difference between the present invention and the conventional constant electrode method is that the hydrogen generation rate of the two-dimensional material can be significantly improved without modifying the catalyst (i.e., the two-dimensional material). When the voltage applied to the electrode is -0.1 V vs. RHE and the moving electrode rise and fall frequency is 3 s, the hydrogen generation rate per unit area under constant electrode conditions is 3.7 μLmin -1 cm 2 , while the hydrogen production rate of the moving electrode of the present invention is 7.3~8.7μL min -1 cm 2 ( Figure 2 ), which is 1.97~2.4 times that under constant electrode conditions; when the voltage applied to the electrode is -0.1 V vs. RHE and the rise and fall speed is 90 mm / s, the hydrogen production rate per unit area under constant electrode conditions is 6μL min -1 cm 2 The hydrogen production rate of the moving electrode of the present invention is 8-12 μL min -1 cm 2 ( Figure 3 ), which is 1.3~2.0 times that under constant electrode conditions; when the voltage applied to the electrode is -0.1 V vs. RHE, the frequency of rise and fall is 3 s, and the rise and fall speed is 90 mm / s, the hydrogen production rate per unit area under constant electrode conditions is 3.3 μL min -1 cm 2 The hydrogen production rate of the dynamic electrode of the present invention is 13.3 μL min -1 cm 2 ( Figure 4 ), which is 4.0 times that under constant electrode conditions.

[0016] (4) The two-dimensional material used in the present invention can be either homemade or commercially available. Without modifying the two-dimensional material, the hydrogen generation rate can be improved by using a moving electrode (a linear motor is connected to the working electrode to control the working electrode to immerse and move out). The process of this method is simple and can improve the electrocatalytic hydrogen evolution performance of the two-dimensional material in situ. This new method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials is of great significance for the large-scale application of the electrocatalytic hydrogen evolution performance of two-dimensional materials and for expanding the application of the electrocatalytic performance of two-dimensional materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 Schematic diagram of hydrogen evolution reaction by electrolysis of water using a moving electrode according to the present invention. Mode I is that the electrode is immersed in the electrolyte; Mode II is that the electrode is completely separated from the electrolyte; Mode III is that the moving electrode descends and is partially immersed in the electrolyte.

[0019] Figure 2 This is the Raman spectrum of the MoS2 moving electrode prepared in Example 1 of the present invention.

[0020] Figure 3 This is the XRD pattern of the MoS2 moving electrode prepared in Example 1 of the present invention.

[0021] Figure 4 The charge amount of the MoS2 moving electrode prepared in Example 1 of the present invention changes at different lifting speeds.

[0022] Figure 5 The voltage applied to the MoS2 moving electrode prepared in Example 1 of the present invention is -0.1 V vs. RHE. When the moving electrode rising and falling frequency is 3 s, a comparison chart of the hydrogen production rate under different rising and falling speeds and constant electrode conditions is shown.

[0023] Figure 6 This is a comparison chart of the accumulated charge of the Mo2C moving electrode and the constant electrode prepared in Example 2 of the present invention.

[0024] Figure 7 A comparison chart of hydrogen production rates under different lifting frequencies and constant electrode conditions when the voltage applied to the Mo2C moving electrode prepared in Example 2 of the present invention is -0.1 V vs. RHE and the moving electrode lifting speed is 90 mm / s.

[0025] Figure 8This is a comparison chart of the charge difference of the Pt-doped MoS2 moving electrode prepared in Example 3 of the present invention under different rising and falling frequencies and constant electrode conditions.

[0026] Fig. 9 The hydrogen production rate diagram of the constant electrode and the moving electrode when the Pt-doped MoS2 moving electrode prepared in Example 3 of the present invention is at -0.1 V vs. RHE, the moving electrode rising and falling frequency is 3 s, and the moving electrode rising and falling speed is 90 mm / s. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The two-dimensional material used in the present invention can be either a commercially available product or homemade according to experimental needs. In this experiment, MoS2 and Pt-doped MoS2 are homemade in the laboratory according to existing methods, that is, a commonly used hydrothermal method is used to directly grow a molybdenum disulfide nanoflower structure. The homemade two-dimensional material is a nanoflower structure directly grown on graphite paper or carbon fiber paper, which is a self-supporting electrode. The two-dimensional materials commonly available on the market are all powders, which require sample preparation before catalytic reactions, and there is no directly grown two-dimensional material that is firm on the substrate. The Mo2C used in the present invention is a commercially available product. Linear motors are common products on the market. Other raw materials are commercially available products. In the present invention, frequency refers to: the residence time of the working electrode moving to the top or bottom.

[0029] Example 1 The method for improving the electrocatalytic hydrogen evolution performance of molybdenum disulfide by using MoS2 as a working electrode is as follows: In the first step, MoS2 nanoflowers were grown on 1×4cm carbon paper by hydrothermal method. 0.609 g ammonium molybdate was first dissolved in 50 mL saturated N2 deionized water, and then 0.57 g thiourea was added to the above solution. 50 mL of the solution and 1×4cm carbon paper were transferred to a 100 mL autoclave and kept at 200 °C for 6 h. After the reaction was completed, it was cooled to room temperature. The MoS2 catalyst was washed with water and dried with nitrogen, and Raman ( Figure 2 ) and XRD ( Figure 3 ) were used to characterize the prepared catalyst. Figure 2 and Figure 3 It proves that the catalyst prepared in this example is a MoS2 catalyst.

[0030] In the second step, in 50 mL of 0.5 M H2SO4, MoS2 / C was used as the working electrode, graphite rod as the counter electrode, and Hg / Hg2SO4 as the reference electrode. The MoS2 catalyst was fixed on a linear motor and the linear motor was used to control the up and down movement of the MoS2 catalyst.

[0031] Figure 1 This is a schematic diagram of the reaction cell when the linear motor controls the up and down movement of the electrode. Before applying voltage to the reaction, the moving electrode system first enters mode I, the electrode is immersed in the electrolyte, and a circuit is formed between the two electrodes to ensure the reaction. As the moving electrode moves upward, the system enters mode II, and the electrode is completely separated from the electrolyte. By setting the movement mode of the linear motor, the moving electrode drops to mode III, the moving electrode is partially immersed in the electrolyte, and is in full contact with the electrolyte. In this process, the moving electrode completes a cycle.

[0032] The third step is to study the electrocatalytic hydrogen evolution performance of MoS2. The electrocatalytic reaction is carried out at a certain voltage by chronopotentiometry, and the amount of transferred charge of the moving electrode and the constant electrode under different conditions is analyzed. Figure 4 The results show that compared with the constant electrode, the moving electrode can generate a higher amount of transferred charge per unit time. When the lifting speed of the MoS2 moving electrode is 5 mm / s, 20 mm / s, 50 mm / s, 90 mm / s and 200 mm / s, the amount of transferred charge is 1.6, 1.9, 2.1, 2.2 and 1.87 respectively.

[0033] The fourth step is to study the hydrogen generation rate under constant electrode and moving electrode conditions. The generated gas is collected by the water displacement method. The movement speed and frequency of the electrode are controlled by a linear motor.

[0034] like Figure 5 The hydrogen generation rate at different lifting speeds when the voltage is -0.1 V vs RHE and the lifting frequency of the moving electrode is 3 s. The lifting speeds of the MoS2 moving electrode are 5 mm / s, 20 mm / s, 50 mm / s, 90 mm / s and 200 mm / s, respectively, and the lifting speed of the constant electrode is 0 mm / s. Under the constant electrode condition, the hydrogen generation rate of water electrolysis is 3.7 μL min -1 cm 2 The hydrogen production rate was the highest when the moving electrode lifting speed was 50 mm / s and 90 mm / s, reaching 8.7 μL min -1 cm 2 , which is 2.4 times that under constant electrode conditions.

[0035] Example 2 The method for improving the electrocatalytic hydrogen evolution performance of molybdenum disulfide by using Mo2C as a working electrode is as follows: The first step is the preparation of Mo2C electrode. 0.017 g Mo2C powder (commercially available) was dispersed in 1 mL of water, 1 mL of isopropanol and 80 µL of Nafion solution, and ultrasonicated for 30 min to ensure the uniform dispersion of Mo2C powder. 20 µL of the dispersion was dropped on 1×4 cm carbon paper and dried naturally for later use. The prepared electrode material was characterized, and XRD proved that it was a hexagonal phase; In the second step, in 50 mL of 0.5 M H2SO4, Mo2C was used as the working electrode, graphite rod as the counter electrode, and Hg / Hg2SO4 as the reference electrode. The Mo2C catalyst was fixed on a linear motor and the linear motor was used to control the up and down movement of the Mo2C catalyst.

[0036] The third step is to study the electrocatalytic hydrogen evolution performance of the Mo2C electrode under the condition of the moving electrode. And compare it with the condition of the constant electrode. The electrocatalytic reaction is carried out under a certain voltage by chronopotentiometry, and the amount of transferred charge of the moving electrode and the constant electrode under different conditions is analyzed. Figure 6 The results show that compared with the constant electrode, the moving electrode can generate a higher amount of transferred charge per unit time.

[0037] The fourth step is to study the hydrogen generation rate under constant electrode and moving electrode conditions. The generated gas is collected by the water displacement method. The movement speed and frequency of the electrode are controlled by a linear motor. The other experimental parameters are fixed, and the movement frequency of the electrode is changed when the voltage applied to the electrode is -0.1 V vs. RHE and the lifting speed is 90 mm / s.

[0038] Under constant electrode conditions, the rate of hydrogen production from water electrolysis was 6 μL min -1 cm 2 When the frequency of the Mo2C moving electrode rises and falls for 1 s, 3 s, and 5 s, the hydrogen production rates of water electrolysis are 12, 10, and 8 μL min, respectively. -1 cm 2 , which are 2, 1.7 and 1.3 times of those under constant electrode conditions, respectively. It can be concluded that the hydrogen production rate of the Mo2C moving electrode is the highest when the rising and falling frequency is 1 s, and the hydrogen production rate at this time is twice that of the constant electrode condition ( Figure 7 ).

[0039] Example 3 The method for improving the electrocatalytic hydrogen evolution performance of molybdenum disulfide by using a Pt-doped MoS2 electrode as a working electrode is as follows: The first step is the preparation of Pt-doped MoS2 electrode. Using 0.5 M H2SO4 as electrolyte, Pt sheet as working electrode, newly prepared MoS2 nanosheet as counter electrode, Hg / Hg2SO4 as reference electrode, the three-electrode system is electrodeposited using an electrochemical workstation, and a suitable potential (such as 2.0 V vs. RHE) is applied to the working electrode Pt sheet to deposit Pt onto the counter electrode MoS2.

[0040] In the second step, in 50 ml of 0.5 M H2SO4, Pt-doped MoS2 was used as the working electrode, graphite rod as the counter electrode, and mercurous sulfate as the reference electrode. The Pt-doped MoS2 catalyst was fixed on a linear motor and the linear motor was used to control the up and down movement of the Pt-doped MoS2 catalyst.

[0041] The third step is to study the hydrogen generation rate under constant electrode and moving electrode conditions. The generated gas is collected by the drainage method. The movement speed and movement frequency of the electrode are controlled by a linear motor. Other experimental parameters are fixed. When the voltage applied to the electrode is -0.1 V vs. RHE and the lifting speed is 90 mm / s, the movement frequency of the electrode is changed. The electrocatalytic reaction is carried out at a certain voltage by chronopotentiometry. The amount of transferred charge of the moving electrode and constant electrode with different lifting frequencies is analyzed. See Figure 8 When the lifting speed of the Pt-doped MoS2 moving electrode is 5 mm / s, 20 mm / s, 50 mm / s, 90 mm / s and 200 mm / s, the transferred charge amounts are 1.6, 1.9, 2.1, 2.2 and 1.87 respectively.

[0042] Under constant electrode conditions, the rate of hydrogen production from water electrolysis was 3.3 μL min -1 cm 2 When the lifting frequency of the Pt-doped MoS2 moving electrode is 1 s and the lifting speed is 90 mm / s, the hydrogen production rate of water electrolysis is 13.3 μL min -1 cm 2 , which is 4.03 times that of the constant electrode condition. Fig. 9 ).

[0043] Example 4 The method for improving the electrocatalytic hydrogen evolution performance of molybdenum disulfide by using Au-doped MoS2 electrode as a working electrode is as follows: The first step is the preparation of Au-doped MoS2 electrode. Using 0.1 mM H2SO4 as electrolyte, Au sheet as working electrode, newly prepared MoS2 nanosheet as counter electrode, and Hg / Hg2SO4 as reference electrode, an electrochemical workstation is used for electrodeposition of the three-electrode system, and a suitable potential (such as 2.0 V vs. RHE) is applied to the working electrode Au sheet to deposit Au onto the counter electrode MoS2.

[0044] In the second step, in 50 ml of 0.5 M H2SO4, Au-doped MoS2 was used as the working electrode, graphite rod as the counter electrode, and mercurous sulfate as the reference electrode. The Au-doped MoS2 catalyst was fixed on a linear motor, and the linear motor was used to control the up and down movement of the Au-doped MoS2 catalyst.

[0045] The third step is to study the electrocatalytic hydrogen evolution performance of MoS2. The electrocatalytic reaction was carried out at a certain voltage by chronopotentiometry, and the transfer charge of the moving electrode and the constant electrode under different conditions was analyzed. The results showed that compared with the constant electrode, the moving electrode can generate a higher transfer charge per unit time.

[0046] The fourth step is to study the hydrogen generation rate under constant electrode and moving electrode conditions. The generated gas is collected by the drainage method. The movement speed and movement frequency of the electrode are controlled by a linear motor. The other experimental parameters are fixed, and the hydrogen generation rate is when the voltage applied to the electrode is -0.05 V vs. RHE, the lifting speed is 90 mm / s, and the lifting frequency is 1 s.

[0047] Example 5 The method for improving the electrocatalytic hydrogen evolution performance of molybdenum disulfide by using a Pd-doped MoS2 electrode as a working electrode is as follows: The first step is the preparation of Pd-doped MoS2 electrode. Using 1 M H2SO4 as electrolyte, Pd sheet as working electrode, newly prepared MoS2 nanosheet as counter electrode, Hg / Hg2SO4 as reference electrode, the three-electrode system is electrodeposited using an electrochemical workstation, and a suitable potential (such as 2.0 V vs. RHE) is applied to the working electrode Pd sheet to deposit Pd onto the counter electrode MoS2.

[0048] In the second step, in 50 ml of 0.5 M H2SO4, Pd-doped MoS2 was used as the working electrode, graphite rod as the counter electrode, and mercurous sulfate as the reference electrode. The Pd-doped MoS2 catalyst was fixed on a linear motor and the linear motor was used to control the up and down movement of the Pd-doped MoS2 catalyst.

[0049] The third step is to study the electrocatalytic hydrogen evolution performance of Pd-doped MoS2. The electrocatalytic reaction was carried out at a certain voltage by chronopotentiometry, and the transfer charge of the moving electrode and the constant electrode under different conditions was analyzed. The results showed that compared with the constant electrode, the moving electrode can generate a higher transfer charge per unit time.

[0050] The fourth step is to study the hydrogen generation rate under constant electrode and moving electrode conditions. The generated gas is collected by the drainage method. The movement speed and movement frequency of the electrode are controlled by a linear motor. The other experimental parameters are fixed, and the hydrogen generation rate is when the voltage applied to the electrode is -0.2 V vs. RHE, the lifting speed is 90 mm / s, and the lifting frequency is 1 s.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for improving the electrocatalytic hydrogen evolution performance of a two-dimensional material using a moving electrode, characterized in that: The two-dimensional material is used as the working electrode, H2SO4 is used as the electrolyte, the carbon rod is used as the counter electrode, and Hg / Hg2SO4 is used as the reference electrode. Then, after the linear motor is connected to the working electrode, the working electrode is controlled to be immersed in and removed from the electrolyte to improve the electrocatalytic hydrogen evolution performance of the two-dimensional material.

2. The method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials using a moving electrode according to claim 1, characterized in that: The two-dimensional material is molybdenum disulfide, molybdenum carbide or metal-doped molybdenum disulfide.

3. The method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials using a moving electrode according to claim 2, characterized in that: The metal in the metal-doped molybdenum disulfide is any one of Pt, Au or Pd.

4. The method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials using a moving electrode according to claim 1, characterized in that: The concentration of the electrolyte is 0.1 mM~1 M.

5. The method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials using a moving electrode according to claim 4, characterized in that: The concentration of the electrolyte was 0.5M.

6. The method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials using a moving electrode according to claim 1, characterized in that: The working unit of the two-dimensional material is -0.05 V ~ -0.2 V vs RHE.

7. The method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials using a moving electrode according to claim 6, characterized in that: The speed of the up and down immersion and removal is 5 mm / s to 200 mm / s.

8. The method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials using a moving electrode according to claim 7, characterized in that: The speed of the up and down immersion and removal is 90 mm / s.

9. The method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials using a moving electrode according to any one of claims 1, 7 or 8, characterized in that: The frequency of the up and down immersion and removal is 0.1 s to 5 s.

10. The method for improving the electrocatalytic hydrogen evolution performance of two-dimensional materials using a moving electrode according to any one of claim 9, characterized in that: The frequency of the up and down immersion and removal is 1 s.

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