Halogen ion doped nickel-iron hydroxide oxygen evolution catalyst as well as preparation method and application thereof

Abstract

The invention relates to a halogen ion-doped nickel-iron hydroxide oxygen evolution catalyst and a preparation method thereof, and the halogen ion-doped nickel-iron hydroxide oxygen evolution catalyst is structurally characterized in that halogen ions are coordinated in a nickel-iron hydroxide laminate, and the number of atoms accounts for 20-40% of the total number of atoms; the atomic number ratio of nickel to iron is (4: 1)-(1: 4); except nickel and iron, the number of atoms of other added cations accounts for 0-20% of the total number of atoms; the halogen ion doped nickel-iron-based hydroxide nanosheet layer grows in a cross-linking manner to form an ordered hollow array, and the thickness of the nanosheet layer is 10-100 nm; the crystal system is a triclinic system, and the space group is R-3m. The catalyst can also grow on carriers such as foamed nickel, foamed nickel, a nickel net, a stainless steel net, foamed iron, an iron net and the like. Under large current density, the catalyst has low oxygen evolution overpotential and Tafel slope, has excellent cycle stability, and shows unpopular application potential in an alkaline electrolytic cell.

Description

Technical Field

[0001] This invention belongs to the technical field of catalytic electrode materials for oxygen evolution in water electrolysis, specifically relating to a halide-doped nickel-iron hydroxide oxygen evolution catalyst, its preparation method, and its application. Background Technology

[0002] Hydrogen energy, as a renewable energy source, has received widespread attention in recent years, and its importance in addressing climate change and achieving sustainable development is increasingly prominent. According to a report by the International Energy Agency (IEA), hydrogen applications include transportation, industrial production, and electricity storage. Hydrogen can be produced in various ways, with water electrolysis being the most ideal green method. Nevertheless, the development and application of hydrogen energy still face multiple challenges. Among these, the economic viability of water electrolysis for hydrogen production is significant; the high cost of electricity required by current technologies directly impacts the market competitiveness of hydrogen. Therefore, developing efficient water electrolysis catalysts to improve the efficiency of water electrolysis and reduce the production cost of hydrogen is crucial for the widespread application of hydrogen energy. The oxygen evolution reaction (OER) is a key reaction determining the efficiency of hydrogen production in the water electrolysis process. In recent years, nickel-iron-based hydroxide catalysts grown on nickel foam or nickel mesh have become a research hotspot for alkaline OER catalysts due to their excellent OER performance and low cost, but some problems still need to be solved. On the one hand, attention needs to be paid to optimizing the synthesis process, controlling costs, and further improving its catalytic activity. On the other hand, the structure and stability of the catalyst also face challenges. Some catalysts are prone to structural reconstruction during long-term operation, leading to the dissolution of active centers. How to further improve its stability is also a key point for nickel-iron-based hydroxide catalysts to be applied in practice. At the same time, its reaction mechanism also urgently needs in-depth theoretical research and experimental verification to optimize the design and promotion of alkaline oxygen evolution electrocatalysts.

[0003] Halogen ion doping has been proven to be an effective method for altering the electronic structure and structural stability of materials. Previous studies have demonstrated that halogen ion doping can change the surface charge distribution and enhance the ionic conductivity of materials. Particularly in energy storage applications: Han et al. synthesized a Cl-doped NiMn LDH lithium-ion battery anode material (with Cl ions accounting for 7.7% of the atomic percentage). The small amount of Cl acts as an active ion carrier, participating in reversible intercalation / deintercalation, providing stable ion channels, and forming a rigid network that restricts the volume change during phase transitions (less than 3%), thus enhancing the material's cycle stability (ACS Appl. Energy Mater. 2020, 3, 4559-4568). Park et al. synthesized a Co2(OH)3Cl material as an energy storage electrode material; Cl ion doping improved the electrode's ionic conductivity (Sci. Rep. 2014, 4, 5785).

[0004] There are also reports on halide ion-doped catalysts used in the field of water electrolysis catalysis. For example, Haq et al. synthesized a Cl-doped PA-Gd-Ni(OH)2, which can improve the catalyst activity and durability. However, the Cl ion doping amount is low and does not change the intrinsic structure of nickel hydroxide (atomic percentage of about 5%, ACS Appl. Mater. Interfaces 2021, 13, 468-479). When testing in seawater electrolyte, Yu et al. promoted the reconstruction of the amorphous NiFeCoP surface into a highly active Cl ion-doped NiFeCo(OH) phase (accounting for about 10% of Cl ions) by Cl adsorbing on the Fe / Co active sites of the catalyst, which significantly improved the OER activity and stability (ACS Catal. 2024, 14, 18322-18332). Sha et al. reported an Ir / NiOOH-Se@OH catalyst, which, when tested in seawater electrolyte, adsorbed Cl on highly dispersed Ir sites (content less than 5%) to form Cl-Ir-O-Ni. Electron bridging enhances the covalent nature of the Ni-O bond, increases the valence state of Ni, and thus activates lattice oxygen around Ni sites to participate in the oxygen evolution reaction (J. Am. Chem. Soc. 2025, 147, 24, 20716–20724). However, in related reported works, halogen doping mainly involves small amounts adsorbed on the hydroxide surface. While this can improve the catalyst's adsorption capacity for oxygen-containing intermediates to some extent and enhance oxygen evolution activity, it cannot guarantee that high-content halide ions will coordinate with metal ions within the layers. No related work has yet been reported to ensure sustained stability while improving performance. In summary, for halogen-doped hydroxide electrolysis oxygen evolution catalysts, halogen ions are usually only adsorbed on the catalyst surface. How to further achieve controllable doping of high-content (atom percentage greater than 20%) halide ions, forming a coordination structure of halide ions within the metal hydroxide layers, fundamentally changing the electronic structure of the material, and improving its oxygen evolution activity while maintaining good stability remains a challenge in this field. Summary of the Invention

[0005] The purpose of this invention is to address the problems of poor conductivity and stability of nickel-iron-based catalysts during oxygen evolution. This invention provides a nickel-iron-based hydroxide oxygen evolution electrocatalyst that can achieve coordination doping of a large number of halide ions between layers, thereby optimizing the overall electron distribution within the layers, improving the adsorption capacity of nickel-iron active centers for oxygen-containing intermediates, and enhancing the electronic conductivity of the material. Its dense cross-linked nanoarray is conducive to increasing the full contact between the material and the electrolyte and the rapid desorption of oxygen, giving the catalyst long-term stability under high current density.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows.

[0007] A halide-doped nickel-iron hydroxide oxygen evolution catalyst, wherein the catalyst material has the following structural characteristics: it has high content of halide-doped nickel-iron hydroxide nanosheets, wherein the number of halogen atoms accounts for 20% to 40% of the total number of atoms; wherein the halogen is one or more combinations of Cl, Br, I, and F.

[0008] Preferably, the halide ions coordinate with nickel and iron in the layer in the form of ionic bonds, and are anchored in the nickel-iron-based hydroxide layer.

[0009] Preferably, the catalyst material has a layer thickness of 10–100 nm; a triclinic crystal system with space group R-3m; and unit cell parameters of a=b=3.27–3.47 Å, c=17.09–17.49 Å; α=β=90°, γ=120°, and a unit cell volume of 159.2–165.2 Å. 3 The halide-doped nickel-iron-based hydroxide nanosheets are cross-linked and grown to form an array structure with a sheet thickness of 10–100 nm.

[0010] Preferably, the atomic ratio of nickel to iron is 4:1 to 1:4; in addition to nickel and iron, metal salts containing cobalt, manganese, chromium, platinum, ruthenium, iridium, lanthanum and cerium cations may also be doped, with the number of doped cations accounting for 0 to 20% of the total number of atoms.

[0011] This invention also provides a method for preparing a halide-doped nickel-iron hydroxide oxygen evolution catalyst. The steps are as follows: weigh nickel, iron, a catalyst growth support that can be added, and other cation metal salts at room temperature, and add them sequentially to a solvent to disperse them evenly by ultrasonication; add the above solution and support into a polytetrafluoroethylene liner, place it in a stainless steel reactor, maintain it at 120-250°C, and react for 5-72 hours; filter to obtain the product, wash it sequentially with methanol and distilled water, and vacuum dry it to obtain a halide-doped nickel-iron hydroxide oxygen evolution electrocatalyst.

[0012] Preferably, in the above preparation method, the anionic composition of the metal salt used in the preparation is one or a combination of two or more of the following: chloride salt, bromide salt, iodide salt, fluoride salt, and nitrate salt.

[0013] Preferably, in the above preparation method, the catalyst growth support that can be added includes nickel foam, nickel mesh, stainless steel mesh, iron foam, and iron mesh.

[0014] Preferably, the solvent used in the preparation is any one or a mixture of two or more of water, methanol, ethanol, ethylene glycol, glycerol, and terpineol.

[0015] The present invention also provides an application of a halide-doped nickel-iron hydroxide oxygen evolution catalyst, wherein the electrocatalyst is used as the working electrode, the electrolyte is a 1M KOH solution, and the counter electrode is a platinum electrode.

[0016] Furthermore, the electrocatalyst requires an overpotential of 222 mV to reach 100 mA cm⁻¹ in a 1 M KOH electrolyte. -2 The current density was measured; after a 1000-hour stability test, the catalyst current decreased by less than 28 mA.

[0017] The beneficial effects of this invention are as follows: This invention provides a method for preparing and applying a halide-doped nickel-iron-based hydroxide catalyst for electrocatalytic oxygen evolution. During the synthesis of the metal hydroxide, the polarity and acidity / alkalinity of the solution are controlled, and the substitution of hydroxyl groups for halide ions in the original metal salt is rationally controlled to achieve a high concentration of halide ion doping, thereby improving the electronic layout of the nickel-iron hydroxide and enhancing its oxygen evolution activity and stability. The features and advantages of this invention are: (1) First, select suitable metal salts and reaction solvents to ensure that the metal salts are fully dissolved, and use a one-step solvothermal reaction to carry out anion exchange while synthesizing metal hydroxides; (2) Screening suitable reaction temperature and reaction time to ensure sufficient anions are anchored between the layers, while synthesizing a nanoarray with a highly cross-linked structure; (3) The prepared nickel-iron-based hydroxide electrode was used for electrocatalytic oxygen evolution reaction and showed good oxygen evolution kinetics and stability. (4) The method of the present invention is simple to operate, low in cost, novel in concept, and suitable for large-scale production synthesis.

[0018] Compared with the prior art, the present invention has the following advantages: (1) This method anchors halide ions in situ to the interlayer of metal hydroxide during the synthesis process. Compared with conventional precipitation and deposition, it can achieve sufficient halide ions to participate in the intralayer coordination, which affects the electron distribution of oxygen evolution active centers in the layer, thereby enabling it to generate oxygen-containing intermediates and precipitate oxygen more quickly, thus improving its oxygen evolution kinetics. (2) By controlling the appropriate solvent, reaction temperature and reaction time, a thin and dense nano array can be formed on the surface of nickel foam, which ensures rapid electron transport and is particularly beneficial for the desorption of micro and nano bubbles and the rapid rupture of large bubbles under high current density, thereby increasing the contact between the electrolyte and the catalyst and having good oxygen evolution stability. (3) The raw materials used in this method are widely available and have low cost; (4) The synthesis process and conditions of this method are relatively simple, which is conducive to large-scale preparation and production; (5) This method has a high utilization rate of raw materials and the synthesis process is pollution-free. Attached Figure Description

[0019] Figure 1 This is a structural diagram of the unit cell structure of Embodiment 1 of the present invention.

[0020] Figure 2 This is a high-magnification scanning electron microscope image of Embodiment 1 of the present invention.

[0021] Figure 3 This is a high-magnification scanning electron microscope image of Embodiment 2 of the present invention.

[0022] Figure 4 This is a high-magnification scanning electron microscope image of Embodiment 3 of the present invention.

[0023] Figure 5 This is a high-magnification scanning electron microscope image of Embodiment 4 of the present invention.

[0024] Figure 6 This is a high-magnification scanning electron microscope image of Embodiment 7 of the present invention.

[0025] Figure 7 This is a scanning electron microscope (SEM) image of the Cl element distribution in Embodiment 1 of the present invention.

[0026] Figure 8 This is the X-ray photoelectron spectrum of Embodiment 1 of the present invention.

[0027] Figure 9 This is a high-resolution transmission electron microscope image of Embodiment 1 of the present invention.

[0028] Figure 10 The X-ray images are those of embodiments 1, 2, 3, and 4 of the present invention.

[0029] Figure 11 The figures are linear scanning voltammetry curves for embodiments 1, 2, 3, 4, and 5 of the present invention.

[0030] Figure 12 The diagrams are Tafel curves for embodiments 1, 2, 3, 4, and 5 of this invention.

[0031] Figure 13 This is a graph showing the constant potential stability of Embodiment 1 of the present invention.

[0032] Figure 14 This is a schematic diagram of the water decomposition equipment assembled in Embodiment 1 of the present invention.

[0033] Figure 15 This is a linear scanning voltammetric curve of the water electrolysis device assembled in Embodiment 1 of the present invention.

[0034] Figure 16 This is a constant current stability curve of the water electrolysis device assembled in Embodiment 1 of the present invention. Detailed Implementation

[0035] The specific embodiments of the present invention will now be described in conjunction with the accompanying drawings and examples to provide a better understanding of the invention. Example

[0036] The preparation method of the halide-doped nickel-iron hydroxide oxygen evolution catalyst in this embodiment is as follows: nickel chloride and ferric chloride are mixed and dissolved in a mixed solvent of water and ethanol at a molar ratio of 1:1, and the concentration of both salts is 0.5 mol / L; the solution is added to a polytetrafluoroethylene liner and reacted at 120°C for 48 h; the solution is then filtered and washed three times with deionized water to obtain the corresponding oxygen evolution catalyst. Example

[0037] The halide-doped nickel-iron hydroxide oxygen evolution catalyst in this embodiment is prepared by the following steps: Sodium bromide, nickel nitrate, and ferric bromide are mixed and dissolved in water at a molar ratio of 4:1, wherein the concentrations of sodium bromide, nickel nitrate, and ferric bromide are 0.8 mol / L, 0.8 mol / L, and 0.2 mol / L, respectively; then an appropriate amount of cobalt chloride is added and fully dissolved, with its concentration controlled at 0.02 mmol / L; the solution is added to a polytetrafluoroethylene liner and subjected to a solvothermal reaction at 150°C for 5 hours, followed by filtration and washing three times with deionized water to obtain the corresponding oxygen evolution catalyst. Example

[0038] The halide-doped nickel-iron hydroxide oxygen evolution catalyst in this embodiment is prepared by the following steps: Sodium iodide, nickel nitrate, and iron iodide are mixed and dissolved in methanol solvent at a molar ratio of 3:1, wherein the concentration of sodium iodide is 0.75 mol / L, the concentration of nickel nitrate is 0.75 mol / L, and the concentration of iron iodide is 0.25 mol / L; then an appropriate amount of manganese bromide is added to dissolve it completely, and its concentration is controlled to be 0.05 mmol / L; the solution is added to a polytetrafluoroethylene liner and reacted solvothermically at 180°C for 12 h; the solution is then washed three times with deionized water to obtain the corresponding oxygen evolution catalyst. Example

[0039] The halide-doped nickel-iron hydroxide oxygen evolution catalyst in this embodiment is prepared by the following steps: Sodium fluoride, nickel nitrate, and iron fluoride are mixed and dissolved in ethylene glycol solvent at a molar ratio of 2:1, wherein the concentrations of sodium fluoride, nickel nitrate, and iron fluoride are 0.67 mol / L, 0.67 mol / L, and 0.33 mol / L; then an appropriate amount of platinum chloride is added to fully dissolve it, controlling its concentration to 0.1 mmol / L; the solution is added to a polytetrafluoroethylene liner and subjected to a solvothermal reaction at 200°C for 24 h; the solution is then washed three times with deionized water to obtain the corresponding oxygen evolution catalyst. Example

[0040] The halide-doped nickel-iron hydroxide oxygen evolution catalyst in this embodiment is prepared by the following steps: nickel chloride and ferric chloride are mixed and dissolved in glycerol solvent at a molar ratio of 1:2, wherein the concentrations of sodium chloride, nickel nitrate, and ferric chloride are 0.33 mol / L, 0.33 mol / L, and 0.67 mol / L, respectively; then an appropriate amount of ruthenium chloride is added and fully dissolved, with its concentration controlled at 0.15 mmol / L; the solution is added to a polytetrafluoroethylene liner and subjected to a solvothermal reaction at 220°C for 36 h; the solution is then washed three times with deionized water to obtain the corresponding oxygen evolution catalyst. Example

[0041] The halide-doped nickel-iron hydroxide oxygen evolution catalyst in this embodiment is prepared by the following steps: nickel chloride and ferric chloride are mixed and dissolved in terpineol solvent at a molar ratio of 1:3, wherein the concentration of nickel chloride is 0.25 mol / L and the concentration of ferric chloride is 0.75 mol / L; then an appropriate amount of cerium chloride is added to dissolve it completely, and its concentration is controlled to be 0.2 mmol / L; the solution is added to a polytetrafluoroethylene liner and reacted solvothermally at 250°C for 72 h; the solution is then washed three times with deionized water to obtain the corresponding oxygen evolution catalyst. Example

[0042] The preparation method of the chloride-doped nickel-iron hydroxide oxygen evolution electrocatalyst supported on nickel foam in this embodiment is as follows: Sodium chloride, nickel nitrate, and ferric chloride are mixed and dissolved in a mixed solvent of water and ethanol at a molar ratio of 1:4, wherein the concentrations of sodium chloride, nickel nitrate, and ferric chloride are 0.5 mol / L, 0.5 mol / L, and 0.5 mol / L, respectively; the solution is added to a polytetrafluoroethylene liner, and then nickel foam is added as a growth support. The reaction is carried out at 120°C for 48 h, and the solution is washed three times with deionized water to obtain the oxygen evolution catalyst supported on the surface of nickel foam.

[0043] Figure 1 This is a schematic diagram of the unit cell structure of Embodiment 1 of the present invention. Figure 1 It is evident that, unlike ordinary small-scale and adsorption-type doping, chlorine atoms form a regular and ordered coordination structure with metal ions within the layers containing nickel and iron, rather than simply adsorbing on the catalyst surface. Single-crystal XRD analysis of the synthesized powder yielded the crystal structure and cell parameters of the corresponding material, allowing for precise determination of the spatial positions and coordination relationships of Ni, Fe, O, and Cl. The side lengths of the cell along the x, y, and z axes are denoted as a, b, and c, respectively, and the angles between side lengths b and c, a and c, and a and b are denoted as α, β, and γ, respectively. The test results demonstrate that the crystal structures of the embodiments all belong to the triclinic crystal system, with space group R-3m, α=β=90°, and γ=120°; their cell side lengths differ, and a comparison of specific parameters can be found in Table 1. Table 1. XRD cell parameters of Examples 1–7 Figures 2 to 6The microstructures of different embodiments are shown. Example 1 shows a spherical structure formed by cross-linked nanosheets under the action of chloride ions; Example 2, a bromine-doped nickel-iron hydroxide, also exhibits a nanoarray structure, but its sheet crystallinity is low, and no obvious cross-linked structure is formed; Example 3 forms a coral-like porous structure under the action of iodide ions; Example 4 forms a rod-like structure under the action of fluoride ions; Example 7 shows a cross-linked nanosheet array of chloride-doped nickel-iron hydroxide loaded on nickel foam. This not only facilitates more thorough contact between the electrolyte and the catalyst surface but also promotes the rapid release of oxygen from its surface, rather than the continuous accumulation of large bubbles, thus increasing the contact resistance of the electrode. Figure 7 This is a scanning electron microscope (SEM) image of the elemental distribution of Cl in Example 1. It can be seen that Cl exhibits a very uniform distribution, with its atomic percentage reaching as high as 30%. Figure 8 The X-ray photoelectron spectroscopy (XPS) of Example 1 shows a very distinct Cl 2p peak near 197 eV, confirming successful high-content Cl doping. XPS analysis reveals that Cl atoms account for 26.5% of the total atoms, which is consistent with... Figure 7 The percentage of Cl atoms obtained were close to the expected values.

[0044] Figure 9 The image shown is a transmission electron microscope image of Embodiment 1 of the present invention. The lattice fringes inside the sheet are obvious, indicating good crystallinity. At the same time, the fringes at the edges are relatively blurred, indicating a certain amorphous interface, which helps electrons to conduct better through the edges of the sheet. The lattice fringes at 0.2506 nm and 0.2856 nm can be observed by measurement, corresponding to the (013) and (012) crystal planes, respectively. Figure 10 The X-ray diffraction patterns are for Examples 1-4. Compared to other anion-doped nickel-iron hydroxides, the interlayer spacing is reduced under the influence of chloride ions. This proves that a large number of chloride ions are introduced into the interlayer, further demonstrating that chloride coordinates with the metal active sites within the layer, forming a regular crystal structure.

[0045] Figure 11 Linear sweep voltammetry curves of different embodiments in 1M KOH at 100 mA cm⁻¹ -2 At the specified current density, the oxygen evolution overpotential of Example 1 is only 222 mV, which is much lower than that of other examples, and it has the best oxygen evolution performance. Figure 12 The diagram shows the Tafel curves for different embodiments, with Embodiment 1 exhibiting the smallest Tafel slope, at only 24.0 mV dec. -1 This indicates that the introduction of chloride ions can effectively improve oxygen evolution kinetics. Through optimization of synthesis conditions, compared with Comparative Examples 1-4, Example 1 also showed the smallest Tafel slope, as detailed in Table 2. Figure 13This is a potentiostatic stability curve for Example 1, showing that the catalyst can achieve a potential stability of 1 A cm⁻¹. -1 It operates stably for 1000 hours under high current density, with an average current decay rate of only 27.2 μA / h. -1 .

[0046] Table 2. Oxygen evolution overpotential and Tafel slope in Examples 1-7 Figure 14 This is a schematic diagram of the water electrolysis device assembled in Example 1. The anode is composed of the components of Example 1, the cathode is made of carbon paper loaded with a commercial Pt / C catalyst, a UTP220 cellulose membrane is placed between the anode and cathode, and the electrolyte used is a 6MKOH solution at 80°C. Figure 15 The image shows the linear sweep voltammetry curve of the water-splitting device assembled in Example 1. In a 6M KOH solution at 80°C, the device can achieve 1 A cm⁻¹ at only 1.88 V. -1 High current density. Figure 16 This is a constant current stability curve of the water splitting device assembled in Example 1. In a 6M KOH solution at 80°C, the device can achieve a constant current stability of 1 A cm⁻¹. -1 The device operated stably for 500 hours at high current density without a significant increase in cell voltage. In conclusion, the water splitting equipment assembled from nickel-iron-based hydroxide oxygen evolution electrocatalyst has good application value.

[0047] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A halide-doped nickel-iron hydroxide oxygen evolution catalyst, characterized in that: The catalyst material is characterized by having high-content nickel-iron-based hydroxide nanosheets doped with halogen ions, wherein the number of halogen atoms accounts for 20% to 40% of the total number of atoms; the halogen is one or more combinations of Cl, Br, I, and F.

2. The halide-doped nickel-iron hydroxide oxygen evolution catalyst according to claim 1, characterized in that: The halide ions coordinate with nickel and iron in the layer in the form of ionic bonds, respectively, and are anchored in the nickel-iron-based hydroxide layer.

3. The halide-doped nickel-iron hydroxide oxygen evolution catalyst according to claim 1, characterized in that: Its lamellar thickness ranges from 10 to 100 nm; its crystal system is triclinic, with space group R-3m; its cell parameters are: a=b=3.27–3.47 Å, c=17.09–17.49 Å; α=β=90°, γ=120°, and its cell volume is 159.2–165.2 Å. 3 The halide-doped nickel-iron-based hydroxide nanosheets are cross-linked and grown to form an array structure with a sheet thickness of 10–100 nm.

4. The halide-doped nickel-iron hydroxide oxygen evolution catalyst according to claim 1, characterized in that: The atomic ratio of nickel to iron is 4:1 to 1:4; in addition to nickel and iron, it can also be doped with metal salts containing cobalt, manganese, chromium, platinum, ruthenium, iridium, lanthanum and cerium cations, with the number of doped cations accounting for 0% to 20% of the total number of atoms.

5. A method for preparing a halide-doped nickel-iron hydroxide oxygen evolution catalyst, characterized in that: The preparation method is as follows: weigh nickel, iron, the catalyst growth support that can be added, and other cation metal salts at room temperature, and add them to the solvent in sequence. Disperse them evenly by ultrasonication. Add the above solution and support to a polytetrafluoroethylene liner, place it in a stainless steel kettle and maintain it at 120-250°C for 5-72 hours. Filter to obtain the product, wash it with methanol and distilled water in sequence, and dry it under vacuum to obtain a halide-doped nickel-iron hydroxide oxygen evolution electrocatalyst.

6. The method for preparing a halide-doped nickel-iron hydroxide oxygen evolution catalyst according to claim 5, characterized in that: The metal salt used in the preparation has anionic composition of one or more of the following: chloride, bromide, iodide, fluoride, and nitrate.

7. The method for preparing a halide-doped nickel-iron hydroxide oxygen evolution catalyst according to claim 5, characterized in that: The catalyst growth supports that can be added include nickel foam, nickel mesh, stainless steel mesh, iron foam, and iron mesh.

8. The method for preparing a halide-doped nickel-iron hydroxide oxygen evolution catalyst according to claim 5, characterized in that: The solvent used in the preparation is any one or a mixture of two or more of the following: water, methanol, ethanol, ethylene glycol, glycerol, and terpineol.

9. The application of a halide-doped nickel-iron hydroxide oxygen evolution catalyst, characterized in that: The electrocatalyst is used as the working electrode, the electrolyte is a 1M KOH solution, and the counter electrode is a platinum electrode.

10. The application of the halide-doped nickel-iron hydroxide oxygen evolution catalyst according to claim 9, characterized in that: The electrocatalyst requires an overpotential of 222 mV to reach 100 mA cm⁻¹ in a 1 M KOH electrolyte. -2 The current density was measured; after a 1000-hour stability test, the catalyst current decreased by less than 28 mA.

Images