Electrocatalyst materials, water electrolysis hydrogen electrode sheets, and methods and devices for making the same

Abstract

The application relates to the technical field of hydrogen production by water electrolysis, in particular to an electrocatalyst material, a hydrogen production electrode sheet for water electrolysis and a preparation method and device thereof. The preparation method of the electrocatalyst material comprises the following steps: mixing NiFe-LDH nanosheets, nickel powder and a functionalized additive system to obtain a first slurry; the composition of the functionalized additive system comprises polytetrafluoroethylene, an anionic polymer and a solvent; the first slurry is subjected to ultrasonic crushing to prepare a second slurry; the second slurry is subjected to shear emulsification to prepare a third slurry; and the third slurry is subjected to ball milling to prepare the electrocatalyst material. The electrocatalyst material has good conductivity, good electrochemical performance and high stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydrogen production by water electrolysis, and particularly relates to an electrocatalyst material, a hydrogen production electrode sheet by water electrolysis, and a preparation method and device thereof. BACKGROUND

[0002] Hydrogen production by water electrolysis is a process of decomposing water into hydrogen and oxygen by electrical energy. Hydrogen production by water electrolysis can effectively store excess renewable energy power and ensure stable operation of the power grid. The high-purity hydrogen produced thereby can be directly applied to fuel cells and high-end chemical industries as a clean energy, and can promote the construction of a more sustainable and environmentally friendly energy system.

[0003] The working principle of hydrogen production by water electrolysis involves two half-reactions, namely, an oxygen evolution reaction (OER) and a hydrogen evolution reaction (HER). The oxygen evolution reaction is a slow kinetic reaction of four-electron transfer, has a high reaction energy barrier, and requires a high overpotential, which is a key bottleneck restricting the overall efficiency. Developing an OER catalyst can effectively reduce the potential and improve the reaction efficiency.

[0004] At present, there have been many reports on OER catalysts, including noble metal-based catalysts (such as IrO2, RuO2, etc.), transition metal-based catalysts (such as NiFe-LDH, Co3O4, NiO / Ni(OH)2, etc.), single-atom catalysts (such as Ni-N-C, Co-SA / G, etc.), perovskite oxides (such as LaCoO3, LaNiO3, etc.), non-oxide catalysts (such as Ni2P, CoP, etc.), etc. Among these materials, layered hydroxide catalysts (LDH) have attracted great interest due to their low cost, high activity, and high alkaline stability. In particular, NiFe-LDH performs particularly well in terms of activity and stability. NiFe-LDH is composed of Ni and Fe metal atoms connected by surface hydroxyl oxygen atoms, has a high active surface area, and a two-dimensional layered structure can provide more active sites. The positively charged layered hydroxide sheets can insert anions between them to achieve rapid charge transfer. However, the layered hydroxide has a two-dimensional layered structure, and there is an interlayer spacing between the sheets, so the conductivity is low and it cannot be used directly.

[0005] A plurality of patent documents such as CN119392290A, CN119530868A, CN118086974A, CN115044939A, CN116926610A, CN119615226A and the like all record methods for preparing NiFe-LDH, but these methods do not solve the problem of low conductivity of NiFe-LDH, in addition, these methods mainly prepare NiFe-LDH on the substrate through hydrothermal growth or electrochemical deposition, the preparation conditions are relatively strict, and in the oxidation environment of high pressure and concentrated alkali, the bonding force between NiFe-LDH and the substrate may change, affecting the long-term stability of the electrode.

[0006] Based on this, it is necessary to develop a NiFe-LDH-based electrocatalyst material with good conductivity, good electrochemical performance and high stability. SUMMARY

[0007] Based on this, one or more embodiments of the present application provide an electrocatalyst material, an electrolytic water hydrogen production electrode sheet and a preparation method and device thereof.

[0008] Specifically includes the following aspects:

[0009] In a first aspect, the present application provides a preparation method of an electrocatalyst material, comprising the following steps:

[0010] Mixing NiFe-LDH nanosheets, nickel powder and a functionalized additive system to obtain a first slurry; the composition of the functionalized additive system includes a bonding agent, an anionic polymer and a solvent;

[0011] Ultrasonic crushing the first slurry to obtain a second slurry;

[0012] Shearing and emulsifying the second slurry to obtain a third slurry;

[0013] Ball milling the third slurry to obtain the electrocatalyst material.

[0014] In the technical scheme of the embodiments of the present application, the NiFe-LDH nanosheets, the nickel powder and the functionalized additive system are mixed, and the NiFe-LDH nanosheets, the nickel powder are uniformly dispersed in the functionalized additive system with a specific composition through ultrasonic crushing, shearing and emulsification and ball milling, and a conductive network is jointly constructed, thereby improving the conductivity of the electrocatalyst material.

[0015] In some embodiments, the preparation method of the electrocatalyst material satisfies at least one of the following conditions:

[0016] (1) The NiFe-LDH nanosheets are in powder form, and the particle size is 100-300 μm;

[0017] (2) the NiFe-LDH nanosheet has a hierarchical porous structure;

[0018] (3) the average particle size of the nickel powder is 100-300 mesh;

[0019] (4) in the functionalized additive system, the weight ratio of the binder to the anionic polymer is 1:(0.25-7).

[0020] In this embodiment, by limiting the particle size and structure of the NiFe-LDH nanosheet and the particle size of the nickel powder, the dispersion uniformity of the nickel powder and the NiFe-LDH nanosheet in the system is further improved, and when the weight ratio of the binder to the anionic polymer in the functionalized additive system is 1:(0.25-7), the electrode substrate has better bonding strength, and the dispersion of the electrocatalyst material is better and the conductivity is better.

[0021] In some embodiments, the preparation method of the NiFe-LDH nanosheet comprises the following steps:

[0022] The nickel-iron metal mixed salt solution is added to the supersaturated sodium bicarbonate solution and mixed, the mixture is stirred at a first rotating speed for 20-40 min, and then filtered to obtain a filter residue; the molar ratio of nickel element to iron element in the nickel-iron metal mixed salt solution is (6-1):1; the concentration of the supersaturated sodium bicarbonate solution is 1.3-2.0 mol / L;

[0023] The filter residue is washed and freeze-dried to obtain the NiFe-LDH nanosheet.

[0024] In this embodiment, the NiFe-LDH nanosheet is prepared by a suitable method, the NiFe-LDH nanosheet has a better hierarchical porous structure, and more active sites are exposed, thereby better improving the conductivity of the electrocatalyst material.

[0025] In some embodiments, the preparation method of the electrocatalyst material satisfies at least one of the following conditions:

[0026] (1) in the step of adding the nickel-iron metal mixed salt solution to the supersaturated sodium bicarbonate solution for mixing, the addition rate of the nickel-iron metal mixed salt solution is 1-10 mL / min;

[0027] (2) in the step of adding the nickel-iron metal mixed salt solution to the supersaturated sodium bicarbonate solution for mixing, the pH of the mixture is maintained at 7.0-8.5;

[0028] (3) the first rotating speed is 200-800 rpm.

[0029] In this embodiment, the nickel-iron metal mixed salt solution is mixed with the supersaturated sodium bicarbonate solution at a suitable rate to ensure that the reaction proceeds at a suitable rate and the pH value of the reaction is maintained within a suitable range, preferably 7.0-8.5, to obtain a good three-dimensional structure, which is conducive to improving the catalytic activity and conductivity.

[0030] In some embodiments, the first slurry, with a total weight percentage of 100%, comprises 30%-80% of the NiFe-LDH nanosheets, 10%-60% of the nickel powder, and 10%-50% of the functionalized additive system.

[0031] The functionalized additive system, with a total weight percentage of 100%, comprises 5%-35% of the anionic polymer, 5%-20% of the binder, and at least 45% of the solvent.

[0032] In this embodiment, the first slurry contains a suitable proportion of NiFe-LDH nanosheets, nickel powder, and functionalized additive system, which can provide sufficient active sites, build a continuous conductive network, and have suitable viscosity and dispersibility, which is conducive to improving the adhesion between the electrocatalyst material and the electrode substrate and uniformly loading and dispersing the NiFe-LDH nanosheets and nickel powder during coating.

[0033] In some embodiments, the first slurry is subjected to ultrasonic crushing to obtain the second slurry, and the processing time is 10-120 min.

[0034] The second slurry is subjected to shear emulsification to obtain the third slurry, which comprises: stirring the second slurry at a second stirring speed for a second stirring time; the second stirring speed is 1000-20000 r / min; and the second stirring time is 4-24 h.

[0035] In this embodiment, the first slurry is subjected to ultrasonic crushing to preliminarily disperse the agglomerates of NiFe-LDH nanosheets and nickel powder formed during mixing, and the ultrasonic method can avoid damaging the hierarchical porous structure of the NiFe-LDH nanosheets. The second slurry is subjected to shearing at a suitable stirring speed to further refine the particles after ultrasonic crushing, fully expose the hierarchical porous structure of the NiFe-LDH, uniformly disperse the nickel powder between the NiFe-LDH particles, and fully contact the binder and the anionic polymer of the functionalized additive system to be uniformly adsorbed on the surfaces of the NiFe-LDH particles and the nickel powder, thereby stabilizing the dispersion system, preventing secondary agglomeration, forming a uniform adhesive layer between the particles, ensuring the stability of the slurry during subsequent coating, and avoiding local excessive clogging of the pores.

[0036] In some embodiments, the step of preparing the electrocatalyst material by ball milling the third slurry comprises:

[0037] The third slurry and zirconium oxide grinding balls are mixed according to a suitable ball-to-material ratio (1-10):1, and then stirred at a third speed for a third time to obtain the electrocatalyst material; the third speed is 200-1000 r / min, and the third time is 12-72 h.

[0038] In this embodiment, the third slurry and zirconium oxide grinding balls are mixed according to a suitable ball-to-material ratio and then ball-milled at a suitable speed, which is beneficial to avoid the destruction of the NiFe-LDH layered structure, further refine the particles, maximize the exposure of active sites, and make the nickel powder more uniformly fill in the gap of the layered structure. After the above ball-milling treatment, the interface between the nickel powder and the NiFe-LDH can be combined more closely, the overall conductivity can be improved, the anionic polymer and the binder in the functional additive can be more uniformly adsorbed on the surface of the particles to form a stable dispersion layer and a more uniform bonding network between the particles, and in addition, a small amount of defects can be introduced on the surface of the NiFe-LDH and the nickel powder through suitable ball-milling treatment. The introduction of oxygen vacancies on the surface of the NiFe-LDH can enhance the adsorption capacity of the reaction intermediates, reduce the OER / HER reaction barrier, and the lattice dislocation of the nickel powder can improve the HER activity, thereby better improving the catalytic activity of the electrocatalyst material.

[0039] In a second aspect, the present application provides an electrocatalyst material prepared by the above preparation method.

[0040] In the technical solution of the embodiments of the present application, the electrocatalyst material prepared by the above preparation method has good compatibility between components, uniform dispersion, good conductivity, and strong catalytic activity.

[0041] In a third aspect, the present application provides a preparation method of an electrode sheet for water electrolysis to produce hydrogen, comprising the following steps:

[0042] The above electrocatalyst material is loaded on the electrode sheet substrate, and the loaded electrode sheet substrate is heated to a first temperature at a first rate under the condition of nitrogen protection, and then kept for a third time;

[0043] The first rate is 2-15 ℃ / min; the first temperature is 120-200 ℃; and the third time is 30-120 min.

[0044] In the technical scheme of the embodiment of the present application, the electrocatalyst material has a suitable viscosity, and can uniformly penetrate the pores of the electrode sheet substrate when being loaded on the electrode sheet substrate, so that the active material is uniformly distributed on the substrate to form a continuous active layer and a conductive network. In the drying and solidification process, uniform temperature rise can effectively reduce the thermal stress in the material and prevent the structure from being damaged due to rapid evaporation of the solvent. Solidification at a suitable temperature can promote the full solidification of the electrocatalyst material and improve the bonding strength with the interface, so that the structure remains intact in long-term electrolysis and the performance attenuation is reduced.

[0045] In a fourth aspect, the present application provides an electrode sheet for water electrolysis hydrogen production prepared by the preparation method described above.

[0046] In the technical scheme of the embodiment of the present application, the electrode sheet for water electrolysis hydrogen production prepared by the preparation method described above has a strong interface bonding, good conductivity, good catalytic performance and long service life.

[0047] In a fifth aspect, the present application provides a water electrolysis hydrogen production device, which comprises the electrode sheet for water electrolysis hydrogen production described above.

[0048] In the technical scheme of the embodiment of the present application, the water electrolysis hydrogen production device comprises the electrode sheet for water electrolysis hydrogen production described above, and thus has the advantages of good conductivity, good catalytic performance and long service life.

[0049] The above description is only a summary of the technical scheme of the present application. In order to more clearly understand the technical means of the present application, the specific embodiments of the present application can be implemented according to the content of the specification, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0050] In order to more clearly illustrate the specific embodiments of the present application or the technical scheme in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creating any creative labor.

[0051] Figure 1 The SEM image of the NiFe-LDH nanosheet of one embodiment of the present application, with a scale of 2.00 pm.

[0052] Figure 2 The XRD image of the NiFe-LDH nanosheet of one embodiment of the present application, with the abscissa being 2theta (°) and the ordinate being intensity.

[0053] Figure 3The conductivity comparison results of the hydrogen production electrode sheets prepared by the electrocatalyst material of Example 1 of the present application and pure nickel powder and pure NiFe-LDH nanosheets, respectively.

[0054] Figure 4 The polarization curve comparison results of the hydrogen production electrode sheets prepared by the electrocatalyst material of Example 1 of the present application and pure nickel powder and pure NiFe-LDH nanosheets, respectively.

[0055] Figure 5 The stability test results of the electrocatalyst material of Example 1 of the present application.

[0056] Figure 6 The life test results of the electrocatalyst material of Example 1 of the present application. DETAILED DESCRIPTION

[0057] The present application will be further described in conjunction with the embodiments and examples. It should be understood that these examples are only used to illustrate the present application and not intended to limit the scope of the present application. Furthermore, it should be understood that those skilled in the art can make various modifications or changes to the present application after reading the content taught by the present application, and these equivalent forms also fall within the protection scope of the appended claims of the present application.

[0058] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein only for the purpose of describing specific embodiments of the present application and is not intended to limit the present application.

[0059] Unless otherwise indicated or contradictory, the terms or phrases used herein have the following meanings:

[0060] The term "and / or" used herein is selected to include any one of two or more related listed items, and also includes any and all combinations of the related listed items, which any and all combinations of the related listed items include any two related listed items, any more related listed items, or all related listed items. It should be noted that when at least two conjunctions selected from "and / or" are combined to connect at least three items, it should be understood that in the present application, the technical solution undoubtedly includes the technical solution connected by "logical and", and also undoubtedly includes the technical solution connected by "logical or". For example, "A and / or B" includes three parallel solutions of A, B and A+B.

[0061] In the present application, "further" and the like are used for the purpose of description, indicating the difference in content, but should not be understood as limiting the protection scope of the present application.

[0062] In the present application, the terms "first", "second", "third", "fourth", etc. in the "first aspect", "second aspect", "third aspect", "fourth aspect", "fifth aspect", etc. are only for the purpose of description and cannot be understood as indicating or implying relative importance or quantity, nor can they be understood as implicitly indicating the importance or quantity of the technical features indicated.

[0063] In the present application, among the technical features described in an open manner, a closed technical solution composed of the listed features is also included, as well as an open technical solution containing the listed features.

[0064] In the present application, with respect to a numerical interval (i.e. a numerical range), if no special instructions are given, it is considered to be continuous within the numerical interval and includes both numerical end points (i.e. the minimum value and the maximum value) of the numerical range and every numerical value between the two numerical end points. If no special instructions are given, when a numerical interval refers only to integers within the numerical interval, it includes both end point integers of the numerical range and every integer between the two end points. In addition, when multiple ranges are provided to describe a feature or a characteristic, these ranges can be combined. In other words, unless otherwise indicated, the ranges disclosed herein should be understood to include any and all sub-ranges encompassed therein.

[0065] In the present application, the temperature parameter, if not specifically limited, allows both constant temperature treatment and variation within a certain temperature range. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuation within a range such as ±5°C, ±4°C, ±3°C, ±2°C, ±1°C is allowed.

[0066] In the present application, weight can be a mass unit known in the material field, such as μg, mg, g, kg, etc.

[0067] In a first aspect, the present application provides a preparation method of an electrocatalyst material, comprising the following steps:

[0068] Mixing NiFe-LDH nanosheets, nickel powder and a functionalized additive system to obtain a first slurry; the composition of the functionalized additive system includes a bonding agent, an anionic polymer and a solvent;

[0069] Ultrasonic crushing of the first slurry to prepare a second slurry;

[0070] Shear emulsification of the second slurry to prepare a third slurry;

[0071] Ball milling of the third slurry to prepare the electrocatalyst material.

[0072] In the technical solution of the embodiments of the present application, the NiFe-LDH nanosheets, nickel powder and functionalized additive system are mixed, and the NiFe-LDH nanosheets and nickel powder are uniformly dispersed in the functionalized additive system with a specific composition through ultrasonic crushing, shear emulsification and ball milling, and a conductive network is jointly constructed, thereby improving the conductivity of the electrocatalyst material.

[0073] In some embodiments, the NiFe-LDH nanosheets have a hierarchical porous structure. Referring to Figure 1 The NiFe-LDH nanosheets of one of the embodiments of the present application have a fluffy porous structure, which can provide more active sites.

[0074] The overpotential of the NiFe-LDH nanosheets prepared by the preparation method of the present application is significantly lower than that of IrO2; in some embodiments, the overpotential of the NiFe-LDH nanosheets of the present application is 250-280 mV, while the overpotential of IrO2 is about 322 mV at 10 mA / cm 2

[0075] In some embodiments, the NiFe-LDH nanosheets are in powder form, and the particle size is 100-300 mesh; the average particle size of the nickel powder is 100-300 mesh. By limiting the particle size of the NiFe-LDH nanosheets and the particle size of the nickel powder, the nickel powder and the NiFe-LDH nanosheets can be uniformly dispersed in the system, and can be refined at the same time in ultrasonic crushing, shear emulsification and ball milling, thereby constructing a conductive network.

[0076] In some embodiments, the weight ratio of the binder and the anionic polymer in the functionalized additive system is 1:(0.25-7). When the functionalized additive system contains a suitable proportion of the binder and the anionic polymer, the electrode substrate has better adhesion strength, and the electrocatalyst material has better dispersibility and better conductivity. For example, the weight ratio of the binder and the anionic polymer can be 1:0.25, 1:0.5, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, etc.

[0077] Alternatively, the binder can be selected from polyvinyl alcohol (PVA), polytetrafluoroethylene (PTFE), polyolefins (PP, PE and other copolymers), polyvinylidene fluoride (PVDF) and the like, which has the effect of binding the catalytically active material and the electrode substrate, and the above-mentioned binder does not affect the catalytic activity and conductivity of the electrocatalyst material.

[0078] ​The anionic polymer plays a good dispersion role through its carrying of anionic groups. Optionally, the anionic polymer can be selected from FuMA-tech ion exchange membrane solution, Dioxide Materials Sustainion ion exchange membrane solution, PiperION anion exchange membrane solution, Quinomer polyaromatic quinoline-based anion resin solution, polynorbornene-based ion exchange resin solution, KMem polyarylalkylene-based anion resin solution, AEMemer polyaromatic anion exchange resin solution, polyarylether sulfone anion exchange resin solution, polyarylpiperidine-based anion exchange resin solution, all-saturated carbon-hydrogen bond anion exchange resin solution, Aemion+TM anion exchange resin solution, perfluoropolyarylether sulfone skeleton anion exchange resin solution, AEMion anion exchange resin solution, etc.

[0079] In some embodiments, the preparation method of the NiFe-LDH nanosheet comprises the following steps:

[0080] After the nickel-iron metal mixed salt solution is added into the supersaturated sodium bicarbonate solution and mixed, the mixture is stirred at a first rotating speed for 20-40 min, filtered, and the filter residue is obtained; the molar ratio of nickel element to iron element in the nickel-iron metal mixed salt solution is (6-1):1; the concentration of the supersaturated sodium bicarbonate solution is 1.3-2.0 mol / L;

[0081] The filter residue is washed and freeze-dried to obtain the NiFe-LDH nanosheet.

[0082] In this embodiment, after the nickel-iron precursor solution is added into the supersaturated sodium bicarbonate solution and mixed, there is undissolved solid sodium bicarbonate, which can ensure that the pH value of the reaction system is maintained at 7-8. By adopting the reverse dropping strategy, the nickel-iron metal mixed salt solution is added into the saturated sodium bicarbonate solution under uniform stirring (first rotating speed). Under the condition that the pH value of the mixture is stable, the nickel-iron metal ions and hydroxyl groups, carbonate ions occur directional co-precipitation to form a layered double metal hydroxide precursor. After the dropping is completed, the mechanical stirring is continued for 20-40 min, which can promote the ripening of the crystal, obtain the NiFe-LDH nanosheet with hierarchical porous structure, and expose more active sites, thereby better improving the conductivity of the electrocatalyst material.

[0083] For example, the molar ratio of nickel element and iron element in the nickel-iron metal mixed salt solution can be 6:1, 5:1, 4:1, 3:1, 2:1, 1:1, etc.; the time for stirring the mixed solution at the first rotating speed can be 20 min, 25 min, 30 min, 35 min, 40 min, etc.; the concentration of the supersaturated sodium bicarbonate solution can be 1.3 mol / L, 1.4 mol / L, 1.5 mol / L, 1.6 mol / L, 1.7 mol / L, 1.8 mol / L, 1.9 mol / L, 2.0 mol / L, etc.

[0084] In some embodiments, in the step of mixing the nickel-iron metal mixed salt solution into the supersaturated sodium bicarbonate solution, the adding rate of the nickel-iron metal mixed salt solution is 1-10 mL / min; a better layered fluffy porous structure can be obtained, providing more active sites.

[0085] For example, the adding rate of the nickel-iron metal mixed salt solution can be 1 mL / min, 2 mL / min, 3 mL / min, 4 mL / min, 5 mL / min, 6 mL / min, 7 mL / min, 8 mL / min, 9 mL / min, 10 mL / min, etc.

[0086] In some embodiments, in the step of mixing the nickel-iron metal mixed salt solution into the supersaturated sodium bicarbonate solution, the pH of the mixed solution is maintained at 7.0-8.5.

[0087] In some embodiments, the first rotating speed is 200-800 rpm, which can better promote the ripening of crystals and the formation of fluffy hierarchical porous structure. For example, the first rotating speed can be 200 rpm, 300 rpm, 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm, etc.

[0088] In some embodiments, after obtaining the filter residue, in the step of washing the filter residue and freeze-drying, the filter residue is washed with deionized water-ethanol alternately for 3-6 times, which can remove the undissolved sodium bicarbonate solids in the washing process, and the freeze-drying time can be 12-24 h, for example, 12 h, 15 h, 18 h, 20 h, 22 h, 24 h, etc.

[0089] In some embodiments, the first slurry, with a total weight percentage of 100%, comprises 30%-80% of the NiFe-LDH nanosheets, 10%-60% of the nickel powder, and 10%-50% of the functionalized additive system; under the premise that the total is 100%, the weight percentage of the NiFe-LDH nanosheets in the first slurry can be freely selected from 30%, 35%, 55%, 60%, 75%, 80%, etc., the weight percentage of the nickel powder can be freely selected from 10%, 20%, 30%, 40%, 50%, 60%, etc., and the weight percentage of the functionalized additive system can be freely selected from 10%, 20%, 35%, 45%, 50%, etc.; for example, in some embodiments, when the weight percentage of the NiFe-LDH nanosheets is 35% and the weight percentage of the nickel powder is 30%, the weight percentage of the functionalized additive system should be 35%.

[0090] In some embodiments, the functionalized additive system, with a total weight percentage of 100%, comprises 5%-35% of the anionic polymer, 5%-20% of the binder, and at least 45% of the solvent; under the premise that the total is 100%, the weight percentage of the anionic polymer in the functionalized additive system can be freely selected from 5%, 10%, 15%, 20%, 25%, 30%, 35%, etc.; the weight percentage of the binder can be freely selected from 5%, 10%, 15%, 20%, etc.; and the solvent contains at least 45%, and can also be 50%, 60%, 70%, 80%, 90%, etc.; for example, in some embodiments, the weight percentage of the anionic polymer is 5%, the weight percentage of the binder is 5%, and the weight percentage of the solvent should be 90%.

[0091] In this embodiment, the first slurry contains the NiFe-LDH nanosheets, the nickel powder, and the functionalized additive system in a suitable ratio, which can provide sufficient active sites, build a continuous conductive network, have a suitable viscosity and dispersibility, and be conducive to improving the adhesion between the electrocatalyst material and the electrode substrate, and can uniformly load and disperse the NiFe-LDH nanosheets and the nickel powder during coating.

[0092] In some embodiments, the first slurry is subjected to ultrasonic crushing to obtain the second slurry, and the processing time is 10-120 min.

[0093] The second slurry is subjected to shear emulsification to obtain the third slurry, which comprises: stirring the second slurry at a second stirring speed for a second stirring time; the second stirring speed is 1000-20000 r / min; and the second stirring time is 4-24 h.

[0094] In this embodiment, the first slurry is subjected to ultrasonic crushing, which can preliminarily disperse the agglomerates of NiFe-LDH nanosheets and nickel powder formed in the mixing process. The ultrasonic method can avoid damage to the hierarchical porous structure of the NiFe-LDH nanosheets. The second slurry is subjected to shearing at a suitable rotating speed, which can further refine the particles after ultrasonic crushing, fully expose the hierarchical porous structure of the NiFe-LDH, uniformly disperse the nickel powder between the NiFe-LDH particles, and fully contact the binder and anionic polymer of the functionalized additive system, so that the functionalized additive system is uniformly adsorbed on the surfaces of the NiFe-LDH particles and the nickel powder, the dispersion system is stabilized, secondary agglomeration is prevented, and a uniform bonding layer is formed between the particles, thereby ensuring the stability of the slurry during subsequent coating and avoiding local excessive clogging of the pores.

[0095] In some embodiments, the step of preparing the electrocatalyst material by ball milling the third slurry includes:

[0096] The third slurry and zirconium oxide grinding balls are mixed at a ball-to-material ratio of 1-10:1, and then stirred at a third rotating speed for a third time to obtain the electrocatalyst material; the third rotating speed is 200-1000 r / min, and the third time is 12-72 h.

[0097] In this embodiment, the third slurry and zirconium oxide grinding balls are mixed at a suitable ball-to-material ratio and subjected to ball milling at a suitable rotating speed, which can avoid damage to the layered structure of the NiFe-LDH, further refine the particles, maximize the exposure of active sites, and more uniformly fill the nickel powder in the gaps of the layered structure. After the above ball milling treatment, the interface between the nickel powder and the NiFe-LDH is combined more closely, the conductivity of the whole is improved, the anionic polymer and the binder in the functionalized additive system are more uniformly adsorbed on the surface of the particles to form a stable dispersion layer and a more uniform bonding network between the particles, and in addition, a small amount of defects can be introduced on the surfaces of the NiFe-LDH and the nickel powder through suitable ball milling treatment. The introduction of oxygen vacancies on the surface of the NiFe-LDH can enhance the adsorption capacity for reaction intermediates, reduce the OER / HER reaction barrier, and the lattice dislocation of the nickel powder can improve the HER activity, thereby better improving the catalytic activity of the electrocatalyst material.

[0098] In a second aspect, the present application provides an electrocatalyst material prepared by the above preparation method.

[0099] In the technical solution of the embodiments of the present application, the electrocatalyst material prepared by the above preparation method has good compatibility between components, uniform dispersion, good conductivity, and strong catalytic activity.

[0100] In a third aspect, the present application provides a preparation method of an electrode sheet for water electrolysis hydrogen production, which includes the following steps: In a third aspect, the present application provides a preparation method of an electrode sheet for water electrolysis hydrogen production, which includes the following steps:

[0101] The electrocatalyst material described above is loaded on the electrode sheet substrate, and the loaded electrode sheet substrate is heated to a first temperature at a first rate under the condition of nitrogen protection, and kept for a third time;

[0102] The first rate is 2-15 ℃ / min; the first temperature is 120-200 ℃; and the third time is 30-120 min.

[0103] At present, when NiFe-LDH type materials are prepared into electrode sheets, a self-supporting method is usually used, such as preparing NiFe-LDH on a nickel foam substrate by electrodeposition or hydrothermal growth method. The disadvantage of this method is that the binding force of NiFe-LDH and the nickel foam substrate will change under the oxidation environment of high pressure and concentrated alkali, resulting in poor long-term stability of the electrode.

[0104] In the technical scheme of the embodiments of the present application, since the electrocatalyst material has a suitable viscosity, it can uniformly penetrate the pores of the substrate when loaded on the electrode sheet substrate, so that the active material is uniformly distributed on the substrate to form a continuous active layer and a conductive network. In the drying and solidification process, uniform heating can effectively reduce the thermal stress in the material and prevent structural damage caused by rapid evaporation of the solvent. Solidification at a suitable temperature can promote the full solidification of the electrocatalyst material, improve the bonding strength with the interface, maintain the structural integrity in long-term electrolysis, and reduce performance decay.

[0105] Optionally, the loading method can be coating, spraying, etc.

[0106] Optionally, the substrate can be a nickel felt substrate, which is pretreated by gradient cleaning with acetone, dilute hydrochloric acid and ethanol before being loaded with the electrocatalyst material.

[0107] In some embodiments, the rate of heating can be 2-15 ℃ / min, and further can be 2-10 ℃ / min.

[0108] The preparation method of the present application has a simple preparation process and does not have harsh condition requirements, and is suitable for large-scale method preparation of electrodes to meet the needs of commercial application.

[0109] In a fourth aspect, the present application provides an electrolytic water hydrogen production electrode sheet prepared by the preparation method described above.

[0110] In the technical scheme of the embodiments of the present application, the electrolytic water hydrogen production electrode sheet prepared by the preparation method described above has strong interface bonding strength, good conductivity, good catalytic performance and long service life.

[0111] In a fifth aspect, the present application provides an electrolytic water hydrogen production device, which comprises the electrolytic water hydrogen production electrode sheet described above.

[0112] The electrolytic water hydrogen production device comprises the electrolytic water hydrogen production electrode sheet, and has the advantages of good electrical conductivity, good catalytic performance, and long service life.

[0113] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application, the specific embodiments of the present application can be implemented according to the content of the specification, and in order to make the above and other purposes, characteristics and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described.

[0114] The following are some specific embodiments.

[0115] In the following specific embodiments, the experimental parameters not specified are preferably referred to the guidance given in the present application document, and can also be referred to the experimental manual in the art or other experimental methods known in the art, or to the recommended experimental conditions of the manufacturer.

[0116] In the following specific embodiments, the raw materials and reagents involved can be obtained commercially or prepared by known means by those skilled in the art.

[0117] I. Preparation of electrocatalyst material and electrolytic water hydrogen production electrode sheet

[0118] Example 1

[0119] 1.1 Preparation of NiFe-LDH nanosheet

[0120] An appropriate amount of nickel nitrate (Ni(NO3)2·6H2O), iron nitrate (Fe(NO3)3·9H2O) and water were weighed and mixed to prepare a nickel-iron metal salt solution, and the molar ratio of nickel element to iron element in the prepared solution was 3:1.

[0121] An appropriate amount of sodium bicarbonate and water were weighed and mixed to prepare a supersaturated sodium bicarbonate solution (about 1.5 mol / L), and the prepared solution had solid sodium bicarbonate not dissolved at the bottom to ensure that the solution remained supersaturated.

[0122] The nickel-iron metal salt solution was added to the supersaturated sodium bicarbonate solution stirred at 500 rpm at a rate of 1 mL / min, and the pH was monitored during the addition process to maintain the pH of the reaction system at 8. The reaction temperature was maintained at 25°C in this alkaline environment, so that the metal ions of the nickel-iron metal salt solution were directionally co-precipitated with hydroxyl groups and carbonate radicals to form a layered double metal hydroxide precursor.

[0123] After the addition was completed, the mixture was stirred at 500 rpm for 20 min, and then vacuum filtered with a Buchner funnel to obtain the filter residue.

[0124] The filter residue was washed with deionized water-ethanol alternately for 3 times, and freeze-dried for 24 h to obtain the NiFe-LDH nanosheets. It was detected that the nanosheets had a hierarchical porous structure (see Figure 1 The freeze-dried NiFe-LDH nanosheets were crushed and passed through a 100-300 mesh screen to obtain the powdered NiFe-LDH nanosheets.

[0125] 1.2 Preparation of an electrocatalyst material.

[0126] 35% of the powdered NiFe-LDH nanosheets, 30% of the nickel powder (particle size 150 mesh), and 35% of the functionalized additive system were mixed in proportion by weight percentage to obtain a first slurry; (the functionalized additive system was a mixture of polytetrafluoroethylene emulsion (Macklin, P816262) and anionic polymer solution (FuMA-tech FAA-3-SOLUT-10 ion exchange membrane solution); the functionalized additive system accounted for 5% of polytetrafluoroethylene, 5% of anionic polymer, and the rest was solution, based on a total weight percentage of 100%);

[0127] The first slurry was ultrasonically broken for 30 min to preliminarily depolymerize the nanoparticle agglomerates to obtain a second slurry;

[0128] The second slurry was transferred into a high-speed shearing emulsifier and treated at 12000 r / min for 6 hours to obtain a third slurry;

[0129] The third slurry was continuously ground for 24 h using a planetary ball mill, with zirconia grinding balls, a ball-to-material ratio of 5:1, and a rotation speed of 600 r / min, to obtain a black third slurry, which was detected to have a viscosity of 500-1500 cp.

[0130] 1.3 Preparation of an electrode sheet for electrolytic water hydrogen production.

[0131] The obtained black third slurry was loaded on a pretreated nickel felt substrate (gradiently cleaned with acetone, dilute hydrochloric acid, and ethanol) through a doctor blade device, and then transferred into a high-temperature oven, which was heated to 180℃ at a rate of 5 ℃ / min under nitrogen protection, and then kept at 180℃ for 60 min to realize strong and tough bonding of the active material and the current collector.

[0132] Example 2

[0133] An electrocatalyst material was prepared by substantially the same method as in Example 1, except that the molar ratio of nickel to iron in the mixed nickel-iron metal salt solution was 4:1. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0134] Example 3

[0135] An electrocatalyst material was prepared using substantially the same method as in Example 1, except that the first slurry was prepared by mixing 30% of the powdered NiFe-LDH nanosheets, 40% of the nickel powder, and 30% of the functionalized additive system in proportion. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0136] Example 4

[0137] An electrocatalyst material was prepared using substantially the same method as in Example 1, except that the composition of the functionalized additive system in the first slurry included 5% polytetrafluoroethylene, 15% anionic polymer, and the remainder was a solution. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0138] Comparative Example 1

[0139] An electrocatalyst material was prepared using substantially the same method as in Example 1, except that the molar ratio of nickel to iron in the nickel-iron metal salt mixed solution used was 7:1. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0140] Comparative Example 2

[0141] An electrocatalyst material was prepared using substantially the same method as in Example 1, except that the first slurry was prepared by mixing 10% of the powdered NiFe-LDH nanosheets, 70% of the nickel powder, and 20% of the functionalized additive system in proportion. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0142] Comparative Example 3

[0143] An electrocatalyst material was prepared using substantially the same method as in Example 1, except that the composition of the functionalized additive system in the first slurry included 5% polytetrafluoroethylene, 40% anionic polymer, and the remainder was a solution. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0144] Comparative Example 4

[0145] An electrocatalyst material was prepared using substantially the same method as in Example 1, except that carbon powder was used instead of nickel powder. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0146] Example 5

[0147] An electrocatalyst material was prepared by substantially the same method as in Example 1, except that the NiFe-LDH nanosheets 20%, nickel powder 40% were used to prepare the electrocatalyst material. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0148] Example 6

[0149] An electrocatalyst material was prepared by substantially the same method as in Example 1, except that the molar ratio of nickel and iron elements selected when preparing the NiFe-LDH nanosheets was 1:1. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0150] Example 7

[0151] An electrocatalyst material was prepared by substantially the same method as in Example 1, except that the composition of the functional additive system in the first slurry contained 5% polytetrafluoroethylene, 35% anionic polymer, and the rest was solution. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0152] Example 8

[0153] An electrocatalyst material was prepared by substantially the same method as in Example 1, except that the composition of the functional additive system in the first slurry contained 25% polytetrafluoroethylene, 10% anionic polymer, and the rest was solution. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0154] Example 9

[0155] An electrocatalyst material was prepared by substantially the same method as in Example 1, except that the addition rate of the nickel-iron metal salt solution was 1 mL / min. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0156] Example 10

[0157] An electrocatalyst material was prepared by substantially the same method as in Example 1, except that the addition rate of the nickel-iron metal salt solution was 10 mL / min. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0158] Example 11

[0159] An electrocatalyst material was prepared by substantially the same method as in Example 1, except that when the mixed nickel-iron metal salt solution was added to the supersaturated sodium bicarbonate solution, the pH value of the reaction system was maintained at 7. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0160] Example 12

[0161] The electrocatalyst material was prepared by substantially the same method as in Example 1, except that the pH value of the reaction system was maintained at 8.5 when the mixed solution of nickel-iron metal salts was added to the supersaturated sodium bicarbonate solution. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0162] Example 13

[0163] The electrocatalyst material was prepared by substantially the same method as in Example 1, except that the ball-to-material ratio was adjusted to 1:1. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0164] Example 14

[0165] The electrocatalyst material was prepared by substantially the same method as in Example 1, except that the third time was adjusted to 12 h. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0166] Example 15

[0167] The electrocatalyst material was prepared by substantially the same method as in Example 1, except that the third rotation speed was adjusted to 2000 rpm. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0168] Example 16

[0169] The electrocatalyst material was prepared by substantially the same method as in Example 1, except that the first rate of temperature rise was adjusted to 15 ℃ / min. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0170] Example 17

[0171] The electrocatalyst material was prepared by substantially the same method as in Example 1, except that the first temperature of temperature rise was adjusted to 130 ℃ / min. The remaining preparation steps, preparation parameters, and raw materials and reagents used in each step were the same as in Example 1.

[0172] II. Characterization of NiFe-LDH Nanosheets

[0173] The SEM image of the NiFe-LDH nanosheets of Example 1 is shown in Figure 1 , showing a fluffy and porous two-dimensional layered structure; and the XRD image is shown in Figure 2Compared with the standard card PDF #51-0463, the characteristic peaks are completely matched, indicating that the NiFe-LDH nanosheet is successfully synthesized.

[0174] III. Electrolysis voltage and decay rate of the electrode sheet battery for electrolysis of water to produce hydrogen.

[0175] Table 1 Electrolysis voltage and decay rate of each example and comparative example

[0176]

[0177] According to Table 1, it can be found that the electrocatalyst material of each example has a low decay rate, and the decay rate is less than 0.5 A / cm 2 The lower electrolysis voltage indicates that the energy input required for the catalyst to drive the reaction (such as OER / HER) is smaller, and the catalytic activity is higher. The electrolysis voltage of each comparative example is significantly higher, and the decay rate is higher; Comparative Example 1 increases the ratio of nickel and iron elements in the preparation process of NiFe-LDH, which weakens the synergistic effect between nickel and iron, resulting in poor catalyst performance; Comparative Example 2 reduces the amount of NiFe-LDH, and since NiFe-LDH is a catalytically active material, reducing the amount results in poor performance; Comparative Example 3 uses less polytetrafluoroethylene and more anionic polymer, resulting in poor stability of the catalyst; Comparative Example 4 uses carbon powder instead of nickel powder, and since carbon powder has poor oxidation resistance and insufficient conductivity, the catalyst has poor performance and a fast decay rate.

[0178] IV. Performance comparison of NiFe-LDH, nickel powder and the electrocatalyst material of the application.

[0179] (1) Electrical conductivity test

[0180] The electrical conductivity of NiFe-LDH, nickel powder and the electrocatalyst material of Example 1 was tested, and the comparison results of electrical conductivity are shown in Table 2. Figure 3 As can be seen from Table 2, Figure 3 the electrical conductivity of NiFe-LDH itself is low, only 9.35 x 10 -7 S / cm. The electrical conductivity of nickel powder itself is high, with a value of 4.35 x 10 -1 S / cm. When nickel powder is added to NiFe-LDH, the electrical conductivity is 3.33 x 10 -5 S / cm, which is improved by two orders of magnitude. The experimental results show that the addition of nickel powder greatly improves the electrical conductivity of NiFe-LDH.

[0181] (2) Electrochemical test

[0182] The NiFe-LDH-based water electrolysis hydrogen electrode sheet was prepared by the same method as in Example 1, except that in the step of preparing the electrocatalyst material, 65% of the powdered NiFe-LDH nanosheet was mixed with 35% of the functional additive system in proportion by weight percentage to obtain a first slurry.

[0183] The NiFe self-supporting electrode sheet was prepared by a hydrothermal method, and the preparation method was referred to the patent CN106381506B.

[0184] The electrode sheet of Example 1 and the NiFe-LDH-based water electrolysis hydrogen electrode sheet were respectively loaded in the electrochemical workstation, and the polarization curve was obtained by linear sweep voltammetry. The comparison results of the polarization curves are shown in Figure 4 . According to Figure 4 It can be found that the polarization curve of NiFe-LDH itself is poor, and the performance is 2.01V@0.5A / cm 2 . After adding nickel powder to improve the conductivity in Example 1, the polarization curve is significantly improved, reaching 2.00V@2.0A / cm 2 . The performance is lower than that of Example 1, and the performance is 2.21V@2.0A / cm 2 .

[0185] (3) Stability test

[0186] The NiFe-LDH catalyst has very poor service life and cannot be tested for service life, so there is no service life test data. The electrode sheet of Example 1 was tested under the condition of 0.5A / cm 2 . The 80-hour constant current test results are shown in Figure 5 . According to Figure 5 It can be found that the electrode sheet of Example 1 has good stability, and the voltage starts to stabilize after 30h. The 350-hour constant current test results are shown in Figure 6 . According to Figure 6 It can be found that the electrode sheet of Example 1 has only a certain fluctuation in voltage in a longer test time, showing good stability.

[0187] All the documents mentioned in the present application are incorporated herein by reference. Unless and to the extent that the incorporated documents conflict with the description and / or technical solutions of the present application, the incorporated documents are incorporated herein by reference in their entireties. When the present application refers to the incorporated documents, the definitions of the relevant technical features, terms, names, phrases, etc. in the incorporated documents are also incorporated herein by reference. When the present application refers to the incorporated documents, the examples and preferred modes of the relevant technical features that are incorporated by reference can also be incorporated herein by reference, provided that the present application can be implemented. It should be understood that when the incorporated content conflicts with the description in the present application, the present application is the priority or is modified according to the description in the present application.

[0188] The technical features of the above-described embodiments and examples can be combined in any suitable manner. In order to make the description concise, not all possible combinations of the technical features in the above-described embodiments and examples are described, however, as long as the combinations of the technical features do not contradict each other, they should be considered to be within the scope of the present disclosure.

[0189] The above-described embodiments only express several embodiments of the present application, but should not be construed as limiting the patentable scope of the present application. It should be pointed out that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, and these are within the scope of the present application. In addition, it should be understood that, after reading the above description of the present application, those skilled in the art can make various changes or modifications to the present application, and the equivalent forms are also within the scope of the present application. It should also be understood that, based on the technical solutions provided by the present application, those skilled in the art can obtain technical solutions through logical analysis, reasoning or limited experiments, and these are within the scope of the claims of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims, and the description can be used to explain the content of the claims.

Claims

1. A method for preparing an electrocatalyst material, characterized in that: The steps include: Mixing NiFe-LDH nanosheets, nickel powder and a functional additive system to obtain a first slurry; the functional additive system comprises a binder, an anionic polymer and a solvent; Ultrasonic crushing the first slurry to obtain a second slurry; Shearing and emulsifying the second slurry to obtain a third slurry; ball milling the third slurry to obtain the electrocatalyst material; The preparation method of the NiFe-LDH nanosheets comprises the following steps: A nickel-iron metal mixed salt solution is added to a supersaturated sodium bicarbonate solution, the mixture is stirred at a first speed for 20 to 40 minutes, and filtered to obtain a filter residue; the nickel-iron metal mixed salt solution has a molar ratio of nickel to iron of (6-1):1; and the concentration of the supersaturated sodium bicarbonate solution is 1.3-2.0 mol / L; Washing the filter residue and freeze-drying it to obtain the NiFe-LDH nanosheets; The first slurry, based on a total weight percentage of 100%, comprises 30%-80% of the NiFe-LDH nanosheets, 10%-60% of the nickel powder, and 10%-50% of the functional additive system; The functional additive system, based on a total weight percentage of 100%, is composed of 5%-35% of the anionic polymer, 5%-20% of the adhesive, and at least 45% of the solvent; The adhesive is selected from polyvinyl alcohol, polytetrafluoroethylene, polyolefins or polyvinylidene fluoride; The anionic polymer plays a dispersing role by carrying anionic groups.

2. The method for preparing an electrocatalyst material according to claim 1, wherein: Meet at least one of the following conditions: (1) The NiFe-LDH nanosheets are in powder form with a particle size of 100-300 mesh; (2) The NiFe-LDH nanosheets have a hierarchical porous structure; (3) The average particle size of the nickel powder is 100-300 mesh; (4) In the functional additive system, the weight ratio of the adhesive to the anionic polymer is 1:(0.25-7).

3. The method for preparing an electrocatalyst material according to claim 1, wherein: Meet at least one of the following conditions: (1) In the step of adding the nickel-iron metal mixed salt solution to the supersaturated sodium bicarbonate solution, the addition rate of the nickel-iron metal mixed salt solution is 1-10 mL / min; (2) in the step of adding the nickel-iron metal mixed salt solution to the supersaturated sodium bicarbonate solution, maintaining the pH of the mixed solution at 7.0-8.5; (3) The first rotation speed is 200-800 rpm.

4. The method for preparing an electrocatalyst material according to claim 1 or 2, characterized in that: The first slurry is subjected to ultrasonic crushing to obtain a second slurry, the processing time being 10-120 min; The step of shearing and emulsifying the second slurry to obtain the third slurry includes: stirring the second slurry at a second speed for a second time; the second speed is 1000-20000 r / min; and the second time is 4-24 hours.

5. The method for preparing an electrocatalyst material according to claim 1 or 2, characterized in that: The step of ball milling the third slurry to obtain the electrocatalyst material comprises: The third slurry and zirconia grinding balls are mixed in a ball-to-material ratio of (1-10):1, and stirred at a third speed for a third time to prepare the electrocatalyst material; the third speed is 200-1000 r / min, and the third time is 12-72 h.

6. An electrocatalyst material prepared by the preparation method according to any one of claims 1 to 5.

7. A method for preparing an electrode sheet for producing hydrogen by electrolysis of water, characterized in that: The steps include: Loading the electrocatalyst material according to claim 6 on an electrode substrate, heating the loaded electrode substrate to a first temperature at a first rate under nitrogen protection, and maintaining the temperature for a third time; The first rate is 2-15°C / min; the first temperature is 120-200°C; and the third time is 30-120 min.

8. An electrode sheet for producing hydrogen by electrolyzing water prepared by the preparation method according to claim 7.

9. A water electrolysis hydrogen production device, characterized in that: The water electrolysis hydrogen production device includes the water electrolysis hydrogen production electrode sheet according to claim 8.

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