CN115161690A

CN115161690A - Preparation method of nickel-molybdenum-iron water electrolysis catalyst, obtained product and application

Info

Publication number: CN115161690A
Application number: CN202210782486.3A
Authority: CN
Inventors: 李纪红; 邓意达; 邵礼; 郑学荣; 王同洲; 王杨; 王浩志; 石沐玲
Original assignee: Hainan University
Current assignee: Hainan University
Priority date: 2022-07-05
Filing date: 2022-07-05
Publication date: 2022-10-11
Anticipated expiration: 2042-07-05

Abstract

The invention discloses a preparation method of a nickel-molybdenum-iron water electrolysis catalyst, an obtained product and application thereof, wherein the method can heat a precursor to the temperature (700-1000 ℃) required by reaction within a few seconds by a rapid thermal impact method, and then rapidly cools the precursor to rapidly generate a substance layer with reaction activity on the surface of a substrate. The method is simple and convenient to operate, rapid in synthesis, and good in property and high in repeatability of the prepared sample. The catalyst has good catalytic activity and excellent catalytic stability in simulated seawater and alkaline seawater, and has wide application prospect.

Description

Preparation method of nickel-molybdenum-iron water electrolysis catalyst, obtained product and application

Technical Field

The invention relates to a preparation method of a nickel-molybdenum-iron water electrolysis catalyst and an obtained product, and also relates to application of the nickel-molybdenum-iron water electrolysis catalyst in the aspect of hydrogen production by electro-catalysis seawater cracking, belonging to the technical field of inorganic functional materials.

Background

Since the introduction of the hydrogen economy by John boccris in the 70's 20 th century, hydrogen energy has been considered one of the cleanest and most promising modes of energy utilization. There are three main synthetic routes to hydrogen fuel: steam reforming of methane, coal gasification and water electrolysis. In steam reforming of methane and coal gasification, methane or coal reacts with steam at high temperature to produce hydrogen and carbon dioxide. Although both methods account for over 95% of the global hydrogen fuel production, it is clear that both methods consume large amounts of fossil fuels and cause environmental pollution problems such as carbon emissions. In contrast, hydrogen production by water splitting as the reverse reaction of hydrogen combustion, with water as the sole feedstock, achieves a closed hydrogen cycle with zero carbon emissions and is therefore considered the greenest and sustainable process, with the current hydrogen consumer market totaling $ 1150 billion and projected to reach $ 1550 billion rapidly by 2022, indicating an increasing interest in hydrogen as an energy carrier. (adv. Mater. 2021, 33, 2007100)

For electrocatalytic water splitting, the anode side Oxygen Evolution Reaction (OER) becomes the bottleneck of the technology due to its slow kinetics due to proton coupled multiple electron transfer steps. To accelerate this process, highly active catalysts are required. Currently, the commonly used oxygen evolution catalysts are iridium-based and ruthenium-based catalysts, but the stability problem caused by long-time catalysis and the expensive production cost restrict the large-scale application of the iridium-based and ruthenium-based catalysts. With the continuous development, a plurality of materials are in the range of 10 mA cm in the non-noble metal catalyst ^-2 The catalytic activity of the catalyst is better than that of a noble metal iridium-based ruthenium-based catalyst under the current density. Such as nickel-based catalytic materials, so far, hybrid catalysis containing active nickel-based compounds and other functional additivesAgents are receiving increasing attention for their advantages of enhanced reaction kinetics and improved structural/performance stability (chem. Eur. J. 2019, 25, 703-713).

Although the research on the activity and stability of nickel-based catalysts in alkaline media has been very intensive, there have been limited reports on the development of nickel-based catalysts in seawater, particularly, on the effective improvement of stability. Seawater accounts for 96.5% of the total water reserves of the earth and is therefore an almost unlimited resource. However, seawater is complex in composition compared to fresh water, and contains a large amount of impurity ions and microorganisms which seriously interfere with the normal electrocatalytic process. According to the literature, the main impurities, namely chloride ions, magnesium ions and calcium ions, have the greatest influence on the catalytic material (ACS Energy Lett. 4, 933-942 (2019)). Chlorine evolution reaction (CLER) at low pH of chloride ions and hypochlorite generation reaction (HCFR) in high pH solutions are the main OER competition reactions, and the presence of chloride ions also destroys the metal passivation film. Magnesium ions and calcium ions form insoluble precipitates on the surface of the catalyst, thereby deactivating the catalyst (Energy environ, sci., 2020, 13, 3253-3268). Therefore, under the background that seawater electrolysis faces many challenges and fresh water resources are increasingly scarce, it is necessary to develop a catalyst for hydrogen production by electrolysis in seawater.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a preparation method of a nickel-molybdenum-iron water electrolysis catalyst and an obtained product, the method adopts a thermal shock method (TSS technology) to convert a metal precursor into a metal catalyst, the operation is simple, the time consumption is short, the preparation process is rapid, and the obtained catalyst has excellent stability in simulated seawater and alkaline seawater and can play a catalytic effect for a long time.

The specific technical scheme of the invention is as follows:

a preparation method of a nickel-molybdenum-iron water electrolysis catalyst comprises the following steps:

(1) Grinding an iron source, a molybdenum source, a nickel source and urea in the presence of a solvent to obtain a precursor paste;

(2) Attaching the precursor paste to a substrate, and naturally drying;

(3) And putting the substrate attached with the precursor on a carbon cloth, electrifying two ends of the carbon cloth, and carrying out at least one thermal shock on the substrate attached with the precursor until the precursor is completely converted into corresponding metal to obtain the nickel-molybdenum-iron electrolytic water catalyst.

Further, the molar ratio of the iron source to the molybdenum source to the nickel source to the urea to the solvent is 5.

Further, the iron source is ferric chloride, the molybdenum source is ammonium molybdate, the nickel source is nickel chloride, and the solvent is absolute ethyl alcohol.

Further, the substrate is nickel mesh, foamed nickel or foamed nickel molybdenum. When the substrate is a nickel mesh, the mesh number of the nickel mesh is generally 40-100.

Further, the grinding was performed at room temperature. After milling, the particles in the paste have an average particle size of less than 150 microns.

Further, the substrate is cleaned prior to use to remove surface impurities. The cleaning step can be as follows: and (3) respectively carrying out ultrasonic treatment on the substrate by using hydrochloric acid, acetone, ethanol and water in sequence.

Further, the precursor paste may be attached to the substrate by coating, dipping, or the like. In one embodiment of the present invention, the precursor paste is fully attached to the substrate by dipping the substrate into the precursor paste for 3-5 min.

Further, the thermal shock is carried out under the protection of gas, and the protection gas is argon, helium or a mixture of the argon and the helium.

Further, when the substrate is nickel mesh, the voltage is set to be 5-20V when the substrate is thermally shocked, and the voltage is set to be 5-10V when the substrate is nickel foam or nickel molybdenum foam. The voltage is provided by a direct current stabilized power supply, and the voltage can enable the precursor to obtain instantaneous high temperature. The heat impact time is 0.1-4 seconds each time. Preferably, the voltage per thermal shock is set to 10v, and the time per shock is 2-4s.

Further, the number of thermal shocks is only required to ensure that the precursor is completely reacted, and the number of thermal shocks can be 1, 2, 3, 4 and the like.

The invention also provides the nickel-molybdenum-iron electrolytic water catalyst obtained by the method, and the catalyst structure is composed of a nickel net substrate and a substance layer which is attached to the substrate and contains a nickel-molybdenum-iron mixed phase. Experiments prove that the nickel-molybdenum-iron electrolyzed water catalyst has high electro-catalytic oxygen evolution activity under an alkaline condition, can keep the stability of catalytic performance for a long time in simulated seawater and alkaline seawater, and has excellent stability.

Further, based on the excellent performance of the nickel-molybdenum-iron water electrolysis catalyst, the invention also provides the application of the nickel-molybdenum-iron catalyst in the fields of water cracking hydrogen production and seawater cracking hydrogen production, wherein the water or seawater cracking hydrogen production is carried out under the alkaline condition.

The invention provides a method for quickly and efficiently preparing a nickel-molybdenum iron electrolysis water catalyst with high activity and high stability for the first time, and compared with a hydrothermal synthesis method and an electrochemical deposition method reported in the prior art, the method has the following beneficial effects:

1. the thermal shock method has simple process flow, simple and convenient operation and rapid preparation process, can heat the precursor to the temperature (700-1000 ℃) required by the reaction within a few seconds, then rapidly cool the precursor, and can rapidly generate a substance layer with reaction activity on the surface of the substrate, and the prepared sample has good property and high repeatability.

2. The invention has high controllability of synthesis conditions, wide sources of prepared main raw materials and obvious advantages of cost compared with the traditional iridium and ruthenium base noble metal catalyst.

3. Compared with a powdery catalyst, the nickel-based catalyst obtained by the invention integrates the current collector electrode and the catalyst into a whole, and the peeling phenomenon cannot occur under the working environment.

4. The catalyst can be directly used as an anode for electrolyzing water, and has higher electrocatalytic oxygen evolution activity and stability under alkaline conditions: the current density was 10 mA cm ^-2 The desired overpotential is optimally only 201 mV.

5. The catalyst is used in simulated seawater (1M KOH + 0.5M NaCl) and 100 mA cm ^-2 The stability under conditions is optimally maintained over 1950 hours.

6. The catalyst of the invention is in alkaline seawater (1M KOH + seawater) at 100 mA cm ^-2 The stability under conditions is optimally maintained over 550 hours. Therefore, the catalyst has the performance of long-term, stable and efficient electrocatalytic water splitting to produce hydrogen in alkaline seawater, and has potential commercial value.

7. The catalyst disclosed by the invention has good catalytic activity and excellent catalytic stability in simulated seawater and alkaline seawater, and has a wide application prospect.

Drawings

FIG. 1: x-ray diffraction (XRD) pattern of NiMoFe-NM (NM is an abbreviation for Nickel Mesh, i.e.nickel Mesh) obtained in example 1.

FIG. 2: raman spectrum of NiMoFe-NM obtained in example 1.

FIG. 3: scanning Electron Microscope (SEM) photographs of the pure nickel mesh substrate in example 1.

FIG. 4: scanning Electron Microscope (SEM) picture of NiMoFe-NM sample in example 1.

FIG. 5: transmission Electron Microscopy (TEM) of the NiMoFe-NM sample from example 1.

FIG. 6: polarization curves for the water splitting evolution of oxygen in alkaline electrolyte (1M KOH) for the NiMoFe-NM sample obtained in example 1, the NiMo-NM sample obtained in comparative example 1, and the NiFe-NM sample obtained in comparative example 2.

FIG. 7: the stability curve for water splitting oxygen evolution in simulated seawater (1M KOH + 0.5M NaCl) for the NiMoFe-NM sample obtained in example 1.

FIG. 8: stability curve for water splitting oxygen evolution in alkaline seawater (1M KOH + seawater) for the NiMoFe-NM sample obtained in example 1.

Detailed Description

The present invention will be further described with reference to the following examples, but the scope of the present invention is not limited to the following examples. It will be apparent to those skilled in the art that variations or modifications of the present invention can be made without departing from the spirit and scope of the invention, and these variations or modifications are also within the scope of the invention.

Example 1

Preparation of a NiMoFe-NM (NM is an abbreviation for Nickel Mesh, nickel gauze) catalyst:

(1) Cutting the nickel screen into strips with the length and width of 1cm x 3cm, respectively ultrasonically cleaning with 0.5M HCL, acetone, ethanol and water for 10 min, and air drying for later use;

(2) Respectively weighing 0.143 g (0.6 mmol) of nickel chloride hexahydrate, 0.247 g (0.2 mmol) of ammonium molybdate, 0.0812 g (0.5 mmol) of anhydrous ferric chloride and 0.36 g (6 mmol) of urea, putting the materials into a mortar, dropwise adding about 0.5ml (8 mmol) of anhydrous ethanol by a dropper while grinding, and continuously grinding until the mixture becomes pasty;

(3) Uniformly coating the paste obtained in the step (2) on the nickel net cleaned and dried in the step (1) by using a brush, or soaking the nickel net obtained in the step (1) in the paste for fully soaking (the soaking time is 3-5 min), and naturally drying the nickel net full of the slurry for later use;

(4) Placing the nickel mesh obtained in the step (3) after drying the load slurry on carbon cloth of 4cm x 4cm under inert protective atmosphere, clamping electrodes of a direct-current stabilized power supply at two ends of the carbon cloth, setting the power supply voltage to be 10V, and thermally shocking for 3 times, wherein the time of each time is 2-3 seconds;

(5) And (5) respectively washing the sample obtained in the step (4) with ethanol and water twice to obtain the NiMoFe-NM catalyst.

FIG. 1 shows the XRD spectrum of the NiMoFe-NM material (NM is an abbreviation for Nickel Mesh, nickel Mesh) prepared by the thermal shock method in example 1, with the position assigned to Nickel Mesh (PDF # 25-2865).

FIG. 2 shows the Raman spectrum of the NiMoFe-NM material prepared by the thermal shock method in example 1. The chemical structure of the NiMoFe-NM material includes localized disordered Mo-O bonds, O-O bonds and Ni-O-Fe states, O-O and Ni-O-Fe vibrations, indicating the presence of mixed nickel iron (oxy) hydroxide structures, whereas Mo-O vibrations characteristic of different phases are attributed to NiMoO ₄ 。

Fig. 3 shows an SEM image of the nickel mesh substrate used in example 1. It can be seen from the figure that the nickel mesh surface is smooth and free of any adherent.

FIG. 4 shows SEM images of the surface (a) and the cross-section (b) of the NiMoFe-NM material obtained in example 1. It can be seen from fig. 4 (a) that a material layer consisting of a mixed phase of nickel, molybdenum and iron was uniformly grown on the nickel mesh substrate after the thermal shock, and fig. 4 (b) shows that the thickness of the material layer was about 0.9 to 2.5 μm.

FIG. 5 shows TEM images of the NiMoFe-NM material obtained in example 1. As can be seen from the figure, the NiMoFe-NM material has both amorphous and crystalline structures. The crystalline structure is mainly mixed nickel iron (oxygen) hydroxide by measuring different lattice fringe spacings, which is consistent with the results of fig. 2 (Raman spectrum).

NiMoFe-NM catalyst is used as a working electrode in an electrolytic cell, a mercury/mercury oxide electrode is used as a reference electrode, a platinum wire is used as a counter electrode, 1M KOH is used as electrolyte, and the current density reaches 10 mA cm ^-2 When the current is measured, the required overpotential is 241 mV, and the current density reaches 100 mA cm ^-2 The desired overpotential is 298 mV. The test needs to be explained that all potentials obtained by taking a mercury/mercury oxide electrode as a reference electrode in the electrocatalysis test are converted into reversible hydrogen electrode potentials in a property diagram, and an external power supply is a main battery of an electrochemical working station.

Example 2

NiMoFe-NF catalyst (NF is an abbreviation for nickel foam in English) was prepared in the same manner as in example 1 except that the nickel mesh was changed to nickel foam (thickness: 0.3 mm). The overpotential was tested in the manner of example 1, and the resulting catalyst was tested in 1M KOH at a current density of 10 mA cm ^-2 The overpotential required is 235 mV.

Example 3

NiMoFe-NMF catalyst (NMF is English abbreviation of foamed nickel molybdenum) was prepared the same as example 1 except that the nickel mesh was changed to foamed nickel molybdenum (thickness 0.3 mm). The overpotential was tested in the manner of example 1, and the resulting catalyst was tested in 1M KOH at a current density of 10 mA cm ^-2 The overpotential required is 201 mV.

Example 4

The same as in example 1, except that the iron source was changed to 0.5 mmol of ferric chloride hexahydrate. The overpotential was measured in the same manner as in example 1, and the obtained catalyst had a current density of 10 mA cm in 1M KOH ^-2 The overpotential required is252 mV。

Example 5

The same as in example 1 except that ammonium molybdate was replaced with 0.2 mmol of sodium molybdate. The overpotential was tested in the manner of example 1, and the resulting catalyst was tested in 1M KOH at a current density of 10 mA cm ^-2 The overpotential required is 263 mV.

Example 6

The same as example 1 except that the thermal shock voltage was changed to 20V. The overpotential was tested in the manner of example 1, and the resulting catalyst was tested in 1M KOH at a current density of 10 mA cm ^-2 The overpotential required was 249mV.

Example 7

The same as in example 1, except that the number of heat shocks was changed to 1. The overpotential was tested in the manner of example 1, and the resulting catalyst was tested in 1M KOH at a current density of 10 mA cm ^-2 The overpotential required was 314mV.

Comparative example 1

A NiMo-NM catalyst was obtained in the same manner as in example 1 except that anhydrous ferric chloride was not added. The overpotential was tested in the manner of example 1, and the resulting catalyst was tested in 1M KOH at a current density of 10 mA cm ^-2 The desired overpotential is 269 mV with a current density of 100 mA cm ^-2 The desired overpotential is 365 mV.

Comparative example 2

The same procedure as in example 1, except that ammonium molybdate was not added, resulted in a NiFe-NM catalyst. The overpotential was tested in the manner of example 1, and the resulting catalyst was tested in 1M KOH at a current density of 10 mA cm ^-2 When the current density is 100 mA cm, the required overpotential is 272mV ^-2 The desired overpotential is 345 mV.

Comparative example 3

Preparation of a NiMoFe-NM (hydrothermal) catalyst:

(2) Respectively weighing 0.143 g (0.6 mmol) of nickel chloride hexahydrate, 0.247 g (0.2 mmol) of ammonium molybdate, 0.0812 g (0.5 mmol) of anhydrous ferric chloride and 0.36 g (6 mmol) of urea, adding 20 ml ultrapure water, uniformly stirring, placing in a 50 ml polytetrafluoroethylene lining, and then placing in the nickel net treated in the step (1);

(3) Packaging the polytetrafluoroethylene lining obtained in the step (2) in a stainless steel reaction kettle, and putting the stainless steel reaction kettle into an oven, wherein the temperature is set to be 180 ℃, and the time is set to be 15 hours;

(4) And (4) cleaning and drying the sample obtained in the step (3) to obtain the NiMoFe-NM (hydrothermal) catalyst.

The overpotential was tested in the manner of example 1, and the resulting NiMoFe-NM (hydrothermal) catalyst was subjected to a current density of 10 mA cm in 1M KOH ^-2 When the current density is 100 mA cm, the required overpotential is 268mV ^-2 The desired overpotential is 327 mV.

Comparative example 4

The same as in example 1, except that the protective atmosphere was changed to air. The overpotential was tested in the manner of example 1, and the resulting catalyst was tested in 1M KOH at a current density of 10 mA cm ^-2 The overpotentials required are 289 mV, respectively.

Performance verification

The prepared catalysts are subjected to electrocatalytic Oxygen Evolution (OER) performance study in a standard three-electrode electrolytic cell, wherein the catalysts prepared in examples and comparative examples are used as working electrodes in the electrolytic cell, a mercury/mercury oxide electrode is used as a reference electrode, a platinum wire is used as a counter electrode, and the electrolyte is 1M KOH, simulated seawater (1M KOH + 0.5M NaCl) or alkaline seawater (1M KOH + seawater). It should be noted that all potentials obtained by using a mercury/mercury oxide electrode as a reference electrode in an electrocatalysis test are converted into reversible hydrogen electrode potentials in a property diagram, and an external power supply is a main battery of an electrochemical working station.

FIG. 6 (a) shows a comparison of the electrocatalytic oxygen evolution properties of the NiMoFe-NM material obtained in example 1, the NiMo-NM material obtained in comparative example 1, the NiFe-NM material obtained in comparative example 2 and a pure nickel mesh (abbreviated as NM) without any treatment in a 1M KOH electrolyte; as can be seen from the figure, the current density reached 10 mA cm in 1M KOH ^-2 The overpotentials required for the above materials (in the order described) are 241 mV, 269 mV, 272mV, 317 m respectivelyAnd V. FIG. 6 (b) is a graph comparing the electrocatalytic oxygen evolution properties of the NiMoFe-NM material obtained in example 1 in 1M KOH, simulated seawater (1M KOH + 0.5M NaCl) and alkaline seawater (1M KOH + seawater), respectively; as can be seen from the figure, the current density of NiMoFe-NM in alkaline medium and simulated seawater reaches 10 mA cm ^-2 While the overpotential differs only by 6 mV, in alkaline seawater media, where the overpotential is 257 mV, the slight decay in activity may be due to microorganisms or bacteria present in the seawater. FIG. 6 (b) shows that the activity of the NiMoFe-NM material is still better in the presence of chloride ions. FIG. 6 (c) shows a comparison of the activity of NiMoFe-NM materials prepared by hot-stamping (NiMoFe-NM from example 1) and hydrothermal (NiMoFe-NM from comparative example 3 (hydrothermal)) respectively; as can be seen from the figure, the activity of the NiMoFe-NM synthesized by adopting the hot punching mode is obviously superior to that of the sample synthesized by adopting the hydrothermal mode, and the current density is 100 mA cm ^-2 The overpotential is different by 49mV. In addition, the activity of the nickel mesh after the heat shock is also improved compared with that of the nickel mesh without any treatment, and the results show that the heat shock method is the optimal method for synthesizing the NiMoFe-NM catalyst. FIG. 6 (d) shows the activity comparison of the samples obtained in example 1, example 2 and example 3, respectively; it can be seen from the figure that the activity of the samples using the foamed nickel molybdenum and the foamed nickel as the substrate is slightly better than that of the samples using the nickel net as the substrate, because the foamed nickel molybdenum and the foamed nickel have three-dimensional structures and have larger specific surface areas so as to be easy to expose more active sites.

FIG. 7 shows the chronopotentiometric diagram of the NiMoFe-NM material prepared by thermal shock method in example 1 in simulated seawater. As can be seen from the results, the catalyst was in simulated seawater (1M KOH + 0.5M NaCl) at 100 mA cm ^-2 At current density, the stability is maintained for more than 1950 hours at the highest energy, and the potential fluctuation is only 8.3%.

FIG. 8 shows the chronopotentiometric graphs of the NiMoFe-NM material prepared by thermal shock method in example 1 in alkaline seawater. As can be seen from the results, the catalyst was in alkaline seawater (1M KOH + seawater) at 100 mA cm ^-2 At current densities, the stability is maintained for more than 550 hours at the highest energy, and the potential fluctuation is only 3.2 percent. The results of fig. 7 and 8 show that NiMoFe-NM has excellent stability and resistance to chloride ion corrosion even in simulated and alkaline seawater.

The catalysts of examples 2 to 3 and comparative examples 1 to 2 were subjected to stability test in alkaline seawater by chronopotentiometry, and when the current density was also set to 100 mA cm ^-2 The results are as follows: the stability of the NiMoFe-NF catalyst obtained in the example 2 is kept for 26 hours; the stability of the NiMoFe-NMF catalyst obtained in example 3 is maintained for 21 hours, which shows that the catalyst stability is greatly improved when the substrate is a nickel net. The stability of the NiMo-NM catalyst obtained in comparative example 1 was maintained for 245 hours, and the stability of the NiFe-NM catalyst obtained in comparative example 2 was maintained for 187 hours, which was much lower than that of the catalyst of the present invention.

Claims

1. A preparation method of a nickel-molybdenum-iron catalyst for water electrolysis is characterized by comprising the following steps:

(2) Attaching the precursor paste to a substrate, and naturally drying;

(3) And putting the substrate attached with the precursor on carbon cloth, electrifying the two ends of the carbon cloth, and carrying out thermal shock on the substrate attached with the precursor at least once until the precursor is completely converted into corresponding metal to obtain the nickel-molybdenum-iron electrolytic water catalyst.

2. The method of claim 1, wherein: the molar ratio of the iron source to the molybdenum source to the nickel source to the urea to the solvent is (1).

3. The method according to claim 1 or 2, characterized in that: the iron source is ferric chloride, the molybdenum source is ammonium molybdate or sodium molybdate, the nickel source is nickel chloride, and the solvent is absolute ethyl alcohol or ethylene glycol.

4. The method of claim 1, wherein: the substrate is nickel mesh, foamed nickel or foamed nickel molybdenum.

5. The method according to claim 4, wherein: the mesh number of the nickel screen is 40-100 meshes.

6. The method according to claim 4, wherein: when in thermal shock, when the substrate is a nickel net, the voltage is set to be 5-20V, and when the substrate is foamed nickel or foamed nickel molybdenum, the voltage is set to be 5-10V; the time of each heat shock is 0.1-4 seconds.

7. The method according to claim 1 or 6, wherein: and in thermal shock, the voltage is set to be 10V, each time is 2-4s, and the thermal shock times are 3.

8. The method of claim 1, wherein: the thermal shock is carried out under the protection of gas, and the protection gas is argon, helium or a mixture of the argon and the helium.

9. The nickel-molybdenum-iron electrolytic water catalyst obtained by the method for producing a nickel-molybdenum-iron electrolytic water catalyst according to any one of claims 1 to 8.

10. The use of the nickel-molybdenum-iron water electrolysis catalyst of claim 9 in the fields of water splitting hydrogen production and seawater splitting hydrogen production.