Electrocatalytic material and preparation and application thereof

Abstract

The application provides an electrocatalytic material and preparation and application thereof, and particularly relates to an electrocatalytic material which has an improvement effect on the oxygen evolution reaction in electrolysis of water, wherein the active component of the electrocatalytic material comprises NiO and La2O3, the molar ratio of Ni and La is (2-10):1; and the structure is a load type structure in which the spherical-like nanoparticles composed of NiO-La2O3 composite nanosheets are loaded on the surface of a foamed nickel, wherein the loading amount of the electrocatalytic material is 0.012-0.018 g / cm 2 , the electrocatalytic material has the characteristics of strong interaction between components and uniform wrapping on the foamed nickel skeleton, and belongs to the field of preparation of electrochemical catalytic materials. The application has the advantages that: the electrocatalytic material has a simple preparation process, mild conditions and low cost; the material can effectively reduce the overpotential of the oxygen evolution reaction; only 198 mV is needed to reach a current density of 10 mA cm ‑2 ; the charge transfer resistance is only 2.38 Omega; and the material can continuously and stably work for 200 hours in a strong alkali environment.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical catalytic materials preparation, and relates to a class of transition metal oxide coupled rare earth metal oxide composite electrocatalytic materials (NiO-La2O3 / NF) that can be used to catalyze the oxygen evolution reaction (OER), as well as their preparation and application. This material has strong inter-component interactions and can effectively accelerate the kinetic performance of the oxygen evolution reaction. Background Technology

[0002] In today's world, human beings' basic needs—food, clothing, shelter, and transportation—are all closely linked to energy supply and consumption; without the energy industry, there would be no modern civilization. However, with the continuous depletion of fossil fuels, the energy crisis is becoming increasingly prominent. Traditional fossil fuels are unclean energy sources; while meeting the vast majority of human society's energy needs, they also release large amounts of wastewater, waste gas, and waste residue into nature, causing a series of global environmental problems. Hydrogen energy, as a green, high-density, and renewable energy carrier, has received widespread attention. In 2020, the National Energy Administration issued a notice on matters related to the preparation of the "14th Five-Year Plan" for renewable energy development, and hydrogen energy has been included in my country's "14th Five-Year Plan." Under the background of the "dual carbon" goal, hydrogen energy has become an indispensable secondary energy form. Hydrogen is widely recognized as an energy carrier with development potential, but in nature, hydrogen mainly exists in compounds. Therefore, developing efficient and sustainable hydrogen production technologies is imperative.

[0003] Artificial hydrogen production technologies mainly include bio-hydrogen production, photocatalytic water splitting, fossil fuel reforming, and water electrolysis. Because bio-hydrogen production and photocatalytic water splitting are relatively inefficient and highly susceptible to environmental influences, fossil fuel reforming is currently the most widely used hydrogen production method in global practice. This method produces over 90% of global hydrogen production, but it inevitably generates greenhouse gases such as carbon dioxide and acid gases such as sulfur dioxide during the reaction process, which contradicts the goal of developing new clean energy sources. Compared to other hydrogen production technologies, water electrolysis is considered a green and efficient method because its raw materials are widely available, the reaction produces only hydrogen and oxygen, and it can convert difficult-to-store electrical energy into easily stored hydrogen energy, making it the most promising sustainable hydrogen production technology.

[0004] The water electrolysis reaction consists of the hydrogen evolution reaction (HER) at the cathode and the oxygen evolution reaction (OER) at the anode. Compared to HER, the OER at the anode is a more complex process, requiring four electron transfers and catalytic kinetic lag, which limits the overall efficiency of the water splitting reaction. This necessitates a potential higher than 1.23V to drive the reaction, and overcoming this limitation typically requires highly active catalysts to achieve efficient water splitting. Currently, noble metal Ir-based or Ru-based materials, such as IrO2 and RuO2, are mainly used to catalyze the OER reaction. Li et al. (ACS Nano, 2023, 18(1): 1214-1225) prepared α-RuO2 / NiO supported on nickel foam through a hydrothermal-calcination-etching-calcination process. Experiments showed that the amorphous / crystalline structure allowed for the introduction of a large number of oxygen vacancies, thereby improving the catalyst's conductivity. Adjusting the d-band center optimized the adsorption and desorption of intermediates, achieving excellent total water splitting reaction kinetics, requiring only 1.75 V to reach 100 mA cm⁻¹. -2 While OER catalysts offer high current density, Ru is relatively expensive. Therefore, developing efficient, readily available, and inexpensive non-precious metal catalysts for OER is one of the current research topics in renewable energy.

[0005] Studies have shown that catalysts represented by transition metals such as Fe, Co, and Ni have great potential in the field of water electrolysis. Due to the abundant reserves of Ni on the Earth's surface, the cost of nickel-based materials is relatively low. Yang et al. (Small, 2021, 17(32): 2101727) used carbon cloth as a substrate and obtained NiO / CeO2 NW@CC by a one-step hydrothermal method followed by calcination of the hydrothermal product in a tube furnace. Only 330mV overpotential was required to reach 50mA cm⁻¹. -2 The results showed that this simple hydrothermal calcination method lattice coupling between CeO2 and NiO was achieved, thereby promoting the generation of oxygen vacancies and accelerating the deep phase reconstruction from NiO to NiOOH, exhibiting good OER catalytic activity. However, it could only operate stably at low current densities for 72 hours, which is not suitable for industrial-grade water electrolysis for hydrogen production under long-term, high-current-density conditions.

[0006] Clearly, the above literature demonstrates that introducing another phase material coupled with a nickel-based compound can effectively improve the catalytic activity and stability of nickel-based catalysts, making it a promising catalyst modification method. However, few studies have focused on developing highly efficient transition metal-based catalysts for hydrogen production via water electrolysis at high current densities. Although nickel-based transition metal catalysts have been extensively studied in alkaline media, they still face several challenges, such as low intrinsic activity and susceptibility to catalyst remodeling. Research indicates that the OER activity of nickel-based transition metal oxides is highly dependent on the degree and extent of their conversion to the corresponding hydroxide, or the active material generated by complete phase transition, thereby improving OER performance. Further structural optimization is still needed to improve the conductivity and long-term stability of nickel-based catalysts, thereby achieving superior electrocatalytic performance to meet practical application requirements. Summary of the Invention

[0007] The purpose of this invention is to provide an electrocatalytic material that improves the electrochemical performance of the oxygen evolution reaction (OER) occurring at the anode of water electrolysis, addressing the problems of high applied potential and poor kinetic performance. Another objective is to provide a method for preparing the aforementioned electrocatalytic material. A further objective is to provide applications of the aforementioned electrocatalytic material. The OER electrocatalytic material prepared according to this method enables the water electrolysis reaction to proceed efficiently under a relatively small applied bias voltage.

[0008] The technical solution of this invention is: an electrocatalytic material, characterized in that the structure of the electrocatalytic material is a supported structure in which spherical nanoparticles composed of NiO-La2O3 composite nanosheets are supported on the surface of nickel foam NF, wherein the loading amount of the active component of the electrocatalytic material is 0.012 ~ 0.018 g / cm³. 2 It features strong inter-component interactions and excellent dispersion of the supported material; the active components are NiO and La₂O₃, with a molar ratio of Ni to La of (2 ~ 10):1. This electrocatalytic material requires only 198 mV overpotential to reach 10 mA cm⁻¹. -2 The current density is such that the charge transfer resistance is only 2.38Ω.

[0009] The present invention also provides a method for preparing the above-mentioned electrocatalytic material, the specific steps of which are as follows:

[0010] (1) Take nickel foam NF and pretreat it in an acid solution, then sonicate, wash and dry it for later use;

[0011] (2) Weigh out soluble nickel salt, soluble lanthanum salt and urea in proportion, add deionized water to prepare electrodeposition solution;

[0012] (3) The treated nickel foam NF in step (1) is immersed in the prepared electrodeposition solution as the cathode and the platinum mesh as the anode. It is deposited for a certain time under constant voltage conditions. Then the obtained nickel foam is washed and dried in sequence to obtain NiLa-LDH / NF precursor.

[0013] (4) The NiLa-LDH / NF precursor obtained in step (3) is calcined to obtain NiO-La2O3 / NF electrocatalytic material.

[0014] Preferably, the acid solution is hydrochloric acid or sulfuric acid solution; the concentration of the acid solution is 0.5 mol / L to 1 mol / L; the ultrasonic temperature is 0 to 5℃, the ultrasonic power is 300 to 400W, and the ultrasonic time is 0.5h to 2h; the drying temperature is 40 to 50℃, and the drying time is 6 to 12h.

[0015] Preferably, the soluble nickel salt is nickel nitrate or nickel chloride; the soluble lanthanum salt is lanthanum nitrate or lanthanum chloride.

[0016] Preferably, the molar ratio of the soluble nickel salt, the soluble lanthanum salt, and urea is (6 ~ 30):3:(0.5 ~ 3); the concentration of the soluble nickel salt in the electrodeposition solution is 0.12 ~ 0.6 mol / L.

[0017] The preferred step (3) has a constant deposition voltage of -0.8V to -1.2V and a deposition time of 300s to 1200s; a drying temperature of 50 to 80℃ and a drying time of 6 to 12h.

[0018] The preferred calcination temperature in step (4) is 300 ~ 400°C, and the calcination time is 1 ~ 3h.

[0019] The present invention also provides an application of the above-mentioned electrocatalytic material in the oxygen evolution reaction during the electrolysis of water to produce hydrogen under alkaline conditions.

[0020] This invention relates to a one-step electrodeposition method to obtain NiLa-LDH supported on nickel foam, followed by vacuum drying and calcination in air to obtain NiO-La2O3 / NF. NiO and La2O3 exhibit synergistic catalytic activity. This electrocatalytic material requires no secondary processing and can be directly applied to electrochemical testing. This electrocatalytic material significantly reduces overpotential in the electrocatalytic water splitting for hydrogen production. Electrochemical performance tests demonstrate that NiO-La2O3 has excellent promoting effects on the electrocatalytic water splitting for hydrogen production and exhibits synergistic catalytic characteristics between the components of the catalytic material.

[0021] Beneficial effects:

[0022] Compared with existing technologies, the present invention has the following advantages and beneficial effects:

[0023] (1) The method for preparing NiO-La2O3 / NF electrocatalytic material described in this invention solves some of the problems existing in nickel-based materials, such as easy aggregation, large catalyst particle size, small specific surface area, and active sites being covered or not fully exposed. It exhibits excellent characteristics of simple preparation method, large specific surface area, uniform particle distribution and good stability, and effectively reduces the starting voltage of oxygen evolution reaction.

[0024] (2) The NiO-La2O3 / NF electrocatalytic material described in this invention is grown in situ on nickel foam and can be directly used for electrochemical testing. This avoids the need to add binders, which would affect the conductivity of the catalyst and improve the electrocatalytic performance.

[0025] (3) In the NiO-La2O3 / NF electrocatalytic material of the present invention, the synergistic effect between NiO and La2O3 enhances the charge transport capability of nickel-based nanocatalysts, solves the shortcomings of poor conductivity and easy aggregation of nickel-based nanocatalysts, and effectively improves the electrocatalytic capability of composite nanocatalysts.

[0026] (4) The NiO-La2O3 / NF electrocatalytic material of the present invention only requires an overpotential of 198 mV to reach 10 mA cm⁻¹. -2 With an overpotential of only 2.38Ω and a charge transfer resistance of only 2.38Ω, it offers broad prospects for the application of water electrolysis in hydrogen production. Attached Figure Description

[0027] Figure 1 The XRD pattern of NiO-La2O3 / NF prepared in Example 1 is shown.

[0028] Figure 2 The XRD pattern of the NiO-La2O3 powder prepared in Example 1 is shown below.

[0029] Figure 3 This is a transmission electron microscope image of the NiO-La2O3 powder prepared in Example 1;

[0030] Figure 4 This is a high-resolution transmission electron microscope image of the NiO-La2O3 powder prepared in Example 1;

[0031] Figure 5 This is a scanning electron microscope image of the NiO-La2O3 / NF prepared in Example 1;

[0032] Figure 6 This is a scanning electron microscope image of the NiO-La2O3 powder prepared in Example 1;

[0033] Figure 7The OER linear sweep voltammetric curves of the five samples obtained in Example 1, Example 2, Example 3, Example 4 and Comparative Example 1 in 1 mol / L KOH electrolyte are shown.

[0034] Figure 8 Electrochemical impedance spectroscopy of five samples obtained in Example 1, Example 2, Example 3, Example 4 and Comparative Example 1 in 1 mol / L KOH electrolyte;

[0035] Figure 9 This is a multi-step chronopotential diagram of the NiO-La2O3 / NF electrocatalytic material prepared in Example 1;

[0036] Figure 10 The NiO-La2O3 / NF electrocatalytic material prepared in Example 1 was tested at 10 mA cm⁻¹. -2 Timing potential diagram under current density. Detailed Implementation

[0037] The present invention will be further described in detail below with reference to specific embodiments. The examples and comparative examples given are only for illustrating the present invention and are not intended to limit the scope of the present invention.

[0038] Unless otherwise specified, the experimental methods used in the following examples and comparative examples are conventional methods.

[0039] Unless otherwise specified, all materials and reagents used in the following examples and comparative examples are commercially available.

[0040] Example 1

[0041] (1) Place the nickel foam in a 0.5 mol / L sulfuric acid solution and sonicate for 2 hours. The sonication temperature is 3℃ and the sonication power is 350W. After washing, dry it in an oven at 50℃ for 6 hours.

[0042] (2) In a standard three-electrode system, 15 mmol of nickel nitrate hexahydrate, 3 mmol of lanthanum nitrate hexahydrate, and 1.5 mmol of urea were dissolved in 50 mL of deionized water as the electrolyte. Using cleaned nickel foam NF and a platinum mesh as the cathode and anode, respectively, NiLa-LDH / NF was prepared by electrodeposition in the three-electrode system for 900 s at a constant potential of -1.0 V. The NF was then dried in a vacuum oven at 60°C for 10 h and then stored for later use.

[0043] (3) The dried NiLa-LDH was placed in a muffle furnace and calcined in an air atmosphere at a temperature of 350°C for 2 hours to obtain NiO-La2O3 / NF.

[0044] The results are as follows:

[0045] Figure 1 This is the XRD pattern of NiO-La2O3 / NF prepared according to the embodiments of the present invention. As can be seen from the figure, under the current process, there are obvious diffraction peaks at 44.5°, 51.7° and 76.3°, which are attributed to the diffraction peaks of the substrate nickel foam.

[0046] Figure 2 This is the XRD pattern of the NiO-La2O3 powder prepared in this embodiment. As can be seen from the figure, under the current process, there are obvious diffraction peaks at 36.9°, 43.2°, 62.9°, 75.6° and 79.5°. These diffraction peaks belong to NiO. Due to the low La content, no diffraction peaks related to La2O3 were observed.

[0047] Figure 3 This is a transmission electron microscope (TEM) image of the NiO-La2O3 powder prepared in this embodiment. As can be seen from the image, the electrocatalytic material NiO-La2O3 exhibits a nanoflower-like structure, with uniform distribution and good morphology. Figure 6 The scanning electron microscope images are consistent.

[0048] Figure 4 This is a high-resolution transmission electron microscope (TEM) image of the NiO-La2O3 powder prepared in this embodiment. The lattice fringes are clearly visible in the image. The 0.207 nm lattice fringes correspond to the (101) crystal plane of NiO, the 0.254 nm lattice fringes correspond to the (110) crystal plane of La2O3, and the 0.286 nm lattice fringes correspond to the (103) crystal plane of La2O3. A distinct heterogeneous interface is also observed, proving that the NiO-La2O3 heterogeneous nanocatalytic material was successfully prepared.

[0049] Figure 5 This is a scanning electron microscope (SEM) image of the NiO-La2O3 / NF prepared in this embodiment. The image shows that the electrocatalytic material is encapsulated on the nickel foam framework and exhibits numerous microcracks, indicating that the electrocatalytic material has been successfully loaded onto the nickel foam at a loading rate of 0.0162 g / cm³. 2 .

[0050] Figure 6 This is a scanning electron microscope (SEM) image of the NiO-La2O3 powder prepared in this embodiment. As the magnification increases, the electrocatalytic material exhibits a nano-flower-like structure, indicating that the electrocatalytic material has a higher specific surface area, which is beneficial for the contact and penetration of the electrolyte.

[0051] Example 2

[0052] (1) Place the nickel foam in a 1 mol / L hydrochloric acid solution and sonicate for 0.5 h at a temperature of 0 °C and a power of 400 W. After washing, dry it in an oven at 45 °C for 8 h.

[0053] (2) In a standard three-electrode system, 30 mmol of nickel nitrate hexahydrate, 3 mmol of lanthanum nitrate hexahydrate, and 0.5 mmol of urea were dissolved in 50 mL of deionized water as the electrolyte. Using cleaned nickel foam NF and a platinum mesh as the cathode and anode, respectively, NiLa-LDH / NF was prepared by electrodeposition in the three-electrode system at a constant potential of -1.2 V for 1200 s. The NF was then dried in a vacuum oven at 80°C for 6 h and then stored for later use.

[0054] (3) The dried NiLa-LDH was placed in a muffle furnace and calcined in an air atmosphere at a temperature of 400°C for 1 hour to obtain NiO-La2O3 / NF.

[0055] The NiO-La2O3 / NF electrocatalyst material prepared in this embodiment exhibits a nanoflower-like structure, indicating that it has a higher specific surface area, which facilitates electrolyte contact and penetration. Furthermore, it is uniformly distributed and has a good morphology. A distinct heterogeneous interface was observed, and the electrocatalyst material is encapsulated on the nickel foam framework, exhibiting numerous microcracks. This indicates that the electrocatalyst material has been successfully loaded onto the nickel foam, with a loading capacity of 0.0173 g / cm³. 2 .

[0056] Example 3

[0057] (1) Place the nickel foam in a 1 mol / L sulfuric acid solution and sonicate for 0.5 h at a temperature of 5 °C and a power of 300 W. After washing, dry it in an oven at 40 °C for 12 h.

[0058] (2) In a standard three-electrode system, 6 mmol of nickel nitrate hexahydrate, 3 mmol of lanthanum nitrate hexahydrate, and 3 mmol of urea were dissolved in 50 mL of deionized water as the electrolyte. Using cleaned nickel foam NF and a platinum mesh as the cathode and anode, respectively, NiLa-LDH / NF was prepared by electrodeposition in the three-electrode system for 300 s at a constant potential of -0.8 V. The NF was then dried in a vacuum oven at 50°C for 12 h and then stored for later use.

[0059] (3) The dried NiLa-LDH was placed in a muffle furnace and calcined in an air atmosphere at a temperature of 300°C for 3 hours to obtain NiO-La2O3 / NF.

[0060] The NiO-La2O3 / NF electrocatalyst material prepared in this embodiment exhibits a nanoflower-like structure, indicating that it has a higher specific surface area, which facilitates electrolyte contact and penetration. Furthermore, it is uniformly distributed and has a good morphology. A distinct heterogeneous interface was observed, and the electrocatalyst material is encapsulated on the nickel foam framework, exhibiting numerous microcracks. This indicates that the electrocatalyst material has been successfully loaded onto the nickel foam, with a loading capacity of 0.0146 g / cm³. 2 .

[0061] Example 4

[0062] (1) Place the nickel foam in a 0.5 mol / L hydrochloric acid solution and sonicate for 1 h at a temperature of 5 °C and a power of 350 W. After washing, dry it in an oven at 50 °C for 10 h.

[0063] (2) In a standard three-electrode system, 15 mmol of nickel chloride hexahydrate, 3 mmol of lanthanum chloride heptahydrate, and 1.5 mmol of urea were dissolved in 50 mL of deionized water as the electrolyte. Using cleaned nickel foam NF and a platinum mesh as the cathode and anode, respectively, NiLa-LDH / NF was prepared by electrodeposition in the three-electrode system at a constant potential of -1.0 V for 600 s. The NF was then dried in a vacuum oven at 60°C for 10 h and stored for later use.

[0064] (3) The dried NiLa-LDH was placed in a muffle furnace and calcined in an air atmosphere at a temperature of 350°C for 2 hours to obtain NiO-La2O3 / NF.

[0065] The NiO-La2O3 / NF electrocatalyst material prepared in this embodiment exhibits a nanoflower-like structure, indicating that it has a higher specific surface area, which facilitates electrolyte contact and penetration. Furthermore, it is uniformly distributed and has a good morphology. A distinct heterogeneous interface was observed, and the electrocatalyst material is encapsulated on the nickel foam framework, exhibiting numerous microcracks. This indicates that the electrocatalyst material has been successfully loaded onto the nickel foam, with a loading capacity of 0.0147 g / cm³. 2 .

[0066] Comparative Example 1

[0067] Preparation of RuO2 electrode material:

[0068] Weigh 2.5 mg RuO2 (commercially available) and add it to a mixture of 400 μL deionized water, 80 μL anhydrous ethanol and 20 μL Nafion solution. Dissolve the solution by sonication for 60 minutes. Then, drop the homogenized RuO2 solution onto nickel foam and dry it at room temperature for later use.

[0069] The above electrocatalytic performance was tested using mercury / mercury oxide as the reference electrode, a graphite electrode as the counter electrode, and the prepared NiO-La2O3 / NF as the working electrode. The electrolyte was 1 mol / L KOH. In linear sweep voltammetry (LSV), the linear scan rate was 5 mV / s, and the iR compensation was 85%. In electrochemical impedance spectroscopy, the frequency range was 10... -2 to 10 5 Hz, amplitude 5 mV. All potentials are converted to potentials relative to the reversible hydrogen electrode (RHE), using the conversion formula E. RHE =E Hg / HgO +0.0592*pH+0.098 V.

[0070] The results are as follows:

[0071] Figure 7 The figures show the OER linear sweep voltammetric curves of five samples obtained in Examples 1, 2, 3, 4, and Comparative Example 1 in a 1 mol / L KOH electrolyte. The sample prepared in Example 1 has the lowest onset potential; therefore, the electrocatalyst material at this ratio exhibits the best catalytic activity. As can be seen from the figures, among these electrocatalyst materials, the NiO-La2O3 / NF electrocatalyst material prepared in Example 1 exhibits the best OER linear sweep voltammetric curve at 10 mA cm⁻¹. -2 It has the lowest onset potential at current density, requiring only 198mV overpotential, exhibits the best electrocatalytic activity, and also has excellent application potential at high current densities.

[0072] Figure 8 Electrochemical impedance spectroscopy (EIS) spectra of five samples obtained in Examples 1, 2, 3, 4, and Comparative Example 1 in 1 mol / L KOH electrolyte. Software fitting analysis revealed that the NiO-La2O3 / NF obtained in Example 1 exhibited the lowest charge transfer resistance, only 2.38 Ω. This indicates that the NiO-La2O3 / NF electrocatalyst has the fastest charge transfer rate and excellent reaction kinetics.

[0073] Figure 9 This is a multi-step chronopotential curve of the NiO-La2O3 / NF electrocatalytic material prepared in Example 1. As shown in the figure, at 10 mA cm⁻¹... -2 20mA cm -2 50mA cm -2 20mA cm -2 and 10mA cm -2After continuous operation at the specified current density for 25 hours, the voltage remained stable without significant fluctuations. This indicates that the NiO-La2O3 / NF electrocatalytic material possesses excellent electrocatalytic activity and stability.

[0074] Figure 10 The NiO-La2O3 / NF electrocatalytic material prepared in Example 1 was tested at 10 mA cm⁻¹. -2 The chronopotential graph shows the chronopotential at current densities of 10 mA cm⁻¹. The graph shows that at 10 mA cm⁻¹... -2 The voltage remained stable for 200 hours under a given current density without significant fluctuations. This indicates that the NiO-La2O3 / NF electrocatalytic material exhibits excellent stability during long-term electrocatalysis.

[0075] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The embodiments and features described in these embodiments can be arbitrarily combined without conflict. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitution methods for the technical features described in the claims. That is, equivalent substitution improvements within this scope are also within the scope of protection of the present invention.

[0076] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An electrocatalytic material, characterized in that, The electrocatalytic material has a supported structure consisting of spherical nanoparticles composed of NiO-La2O3 composite nanosheets loaded onto the surface of nickel foam NF, wherein the loading amount of the active component of the electrocatalytic material is 0.012 ~ 0.018 g / cm³. 2 The active components are NiO and La2O3, with a molar ratio of Ni to La of (2 ~ 10):

1.

2. A method for preparing the electrocatalytic material as described in claim 1, comprising the following specific steps: (1) Take nickel foam NF and pretreat it in an acid solution, then sonicate, wash and dry it for later use; (2) Weigh out soluble nickel salt, soluble lanthanum salt and urea in proportion, add deionized water to prepare electrodeposition solution; (3) The treated nickel foam NF in step (1) is immersed in the prepared electrodeposition solution as the cathode and the platinum mesh as the anode. It is deposited for a certain time under constant voltage conditions. Then the obtained nickel foam is washed and dried in sequence to obtain NiLa-LDH / NF precursor. (4) The NiLa-LDH / NF precursor obtained in step (3) is calcined to obtain NiO-La2O3 / NF electrocatalytic material.

3. The method according to claim 2, characterized in that... The acid solution is hydrochloric acid or sulfuric acid solution; the concentration of the acid solution is 0.5 mol / L ~ 1 mol / L; the ultrasonic temperature is 0 ~ 5℃, the ultrasonic power is 300 ~ 400W, and the ultrasonic time is 0.5h ~ 2h; the drying temperature is 40 ~ 50℃, and the drying time is 6 ~ 12h.

4. The method according to claim 2, characterized in that... The soluble nickel salt is nickel nitrate or nickel chloride; the soluble lanthanum salt is lanthanum nitrate or lanthanum chloride.

5. The method according to claim 2, characterized in that... The molar ratio of the soluble nickel salt, soluble lanthanum salt and urea is (6 ~ 30):3:(0.5 ~ 3); the concentration of the soluble nickel salt in the electrodeposition solution is 0.12 ~ 0.6 mol / L.

6. The method according to claim 2, characterized in that... In step (3), the constant voltage for deposition is -0.8V to -1.2V, the deposition time is 300s to 1200s, the drying temperature is 50 to 80℃, and the drying time is 6 to 12h.

7. The method according to claim 2, characterized in that... The calcination temperature in step (4) is 300 ~ 400℃ and the calcination time is 1 ~ 3h.

8. The application of the electrocatalytic material as described in claim 1 in the oxygen evolution reaction during the electrolysis of water to produce hydrogen under alkaline conditions.

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