Nickel-cobalt-iron alkaline electrolyzed water catalyst based on quenching process and preparation method

Abstract

The invention provides a nickel-cobalt-iron alkaline electrolytic water catalyst based on a quenching process, the chemical general formula is NixCoyFezOx + y + z + 1, x + y + z is more than 0 and less than or equal to 4, x + y + z is more than 0 and less than or equal to 2, y is more than or equal to 0 and less than or equal to 1, and z is more than or equal to 0 and less than or equal to 1, and the preparation method comprises the following steps: pre-treating a nickel base material, preparing a precursor solution, dipping, calcining and quenching, and repeatedly dipping, calcining and quenching. The invention further provides application, and the nickel-cobalt-iron alkaline electrolyzed water catalyst based on the quenching process is used for electrolyzed water catalysis. The metal-oxygen strong bonding effect is formed through cooperation of multiple metal components, and a large number of oxygen vacancies and surface defects are generated through induction of quenching treatment. According to the present invention, the number of the active sites is increased, the electronic structure is optimized, the adsorption and the dissociation of the water molecules are promoted, and the dissolution and the shedding of the active components during the long-time operation are effectively prevented.

Description

Technical Field

[0001] This invention belongs to the field of catalyst technology, specifically relating to a nickel-cobalt-iron alkaline water electrolysis catalyst based on a quenching process, its preparation method, and its application. Background Technology

[0002] With the advancement of the green energy transition, hydrogen energy, as a clean energy carrier, has received widespread attention. Alkaline water electrolysis for hydrogen production is one of the most mature large-scale hydrogen production technologies, but its widespread application is limited by high overpotential and energy consumption. Developing efficient, stable, and low-cost water electrolysis catalysts is key to reducing the cost of hydrogen production.

[0003] Currently, while noble metal-based catalysts (such as Pt / C, IrO2, and RuO2) exhibit excellent performance, their high cost and scarcity limit their large-scale industrial application. Transition metals (Ni, Co, Fe, etc.) have become ideal alternative materials due to their abundant reserves, low cost, and tunable electronic structures. Existing research shows that the synergistic effect of multiple metals can significantly improve catalytic performance; for example, the nickel-iron system has good oxygen evolution reaction (OER) activity, the cobalt-iron combination can optimize the electronic structure, and the nickel-cobalt composite can improve hydrogen evolution reaction (HER) performance.

[0004] The alkaline water electrolysis hydrogen production industry generally faces the challenges of catalyst performance degradation and insufficient catalytic efficiency. Specifically, this manifests in the following three aspects: (1) Insufficient exposure of catalytic active sites, leading to limited intrinsic activity; (2) Poor catalyst stability, with active components easily dissolving or detaching after prolonged operation; (3) Complex catalyst preparation processes, making it difficult to precisely control the structure and composition of active sites. Patent CN118773654A discloses a Ni... m Fe n LDH / CeO 2-x / NF catalysts, through electrodeposition and high-temperature annealing processes, introduce low-spin Fe doping, heterogeneous interfaces, and abundant oxygen vacancies to enhance the catalytic activity of the electrode. Patent CN120738705A proposes a cobalt-manganese oxide-porous anion exchange membrane composite system, which introduces different oxygen vacancy concentrations through acid etching to optimize the electronic structure, improving the catalyst's stability and catalytic activity in high-temperature, strongly alkaline environments, thereby accelerating the catalytic water electrolysis reaction rate. Patent CN115478290B proposes a method for rapidly preparing NiFe-LDH nickel-based electrodes, which can firmly bind the catalyst to the nickel substrate, contributing to improved catalyst stability. However, these methods still suffer from complex preparation processes, limited catalytic efficiency, and high costs.

[0005] Quenching, as an effective material treatment method, can optimize the electronic structure and surface properties of catalysts by inducing lattice distortion, increasing surface defects and oxygen vacancies through rapid cooling. However, there are currently no reports on applying this technology to regulate the entire process of alkaline water electrolysis in a nickel-cobalt-iron system. Summary of the Invention

[0006] The technical problem this invention aims to solve is to address the shortcomings of the prior art by providing a nickel-cobalt-iron alkaline water electrolysis catalyst based on a quenching process, its preparation method, and its application. This method utilizes the synergistic formation of strong metal-oxygen bonds by multiple metal components, along with the large number of oxygen vacancies and surface defects induced by the quenching treatment. This not only increases the number of active sites but also optimizes the electronic structure, promotes the adsorption and dissociation of water molecules, and effectively prevents the dissolution and shedding of active components during long-term operation.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a nickel-cobalt-iron alkaline water electrolysis catalyst based on a quenching process, wherein the general chemical formula of the nickel-cobalt-iron alkaline water electrolysis catalyst based on the quenching process is Ni. x Co y Fe z O x+y+z+1 , where 0 < x + y + z ≤ 4, and 0 ≤ x ≤ 2, 0 ≤ y ≤ 1, 0 ≤ z ≤ 1.

[0008] This invention also provides a method for preparing the above-mentioned nickel-cobalt-iron alkaline water electrolysis catalyst based on a quenching process, the method being: S1. Pretreatment of nickel substrate: After cleaning and drying the nickel substrate, a pretreated nickel substrate is obtained. S2. Preparation of precursor solution: The main salt, dispersant, and antioxidant were added to deionized water and mixed thoroughly to obtain the precursor solution. The main salt is a mixture of nickel salt, cobalt salt and ferrous salt or a mixture of nickel salt, cobalt salt and ferrous salt; S3, Impregnation-calcination-quenching: S301, Impregnation: The pretreated nickel substrate obtained in S1 is immersed in the precursor solution obtained in S2 for 2 min to 10 min, then removed and dried to obtain the dried substrate. S302, calcination: The dried substrate obtained in S301 was heated from room temperature to 300℃~750℃ at a heating rate of 5℃ / min~20℃ / min and calcined at a constant temperature for 0.5h~1h to obtain the calcined substrate. S303, Quenching: The calcined substrate obtained from S302 is rapidly immersed in an ice-water mixture or liquid nitrogen for quenching, washed with deionized water, and dried to obtain the catalyst precursor. The present invention involves fully calcining the dried substrate under a certain heating and holding time to ensure the orderly transformation of the crystal structure, and then rapidly immersing it in a low temperature source for quenching, using the extreme temperature difference to induce lattice distortion.

[0009] S4. Repeat the impregnation-calcination-quenching process in step S3 multiple times to obtain a nickel-cobalt-iron alkaline water electrolysis catalyst based on the quenching process.

[0010] This invention utilizes the similar ionic radii of iron, cobalt, and nickel, allowing ions to randomly replace each other through a thermally activated diffusion process at high temperatures. The system maintains electroneutrality by adjusting cation vacancy concentration and ion valence states, ultimately forming a thermodynamically stable and homogeneous solid solution phase driven by entropy increase. In this solid solution phase, the electronegativity of the metal and oxygen, along with the overlap of metal d orbitals and oxygen 2p orbitals, results in a mixture of ionic and covalent metal-oxygen bonds. Within this solid solution system, Fe, Co, and Ni all possess multiple valence states. 2+ / Fe 3+ Co 2+ / Co 3+ Ni 2+ / Ni 3+ When ions of different valence states coexist, in order to maintain the overall electroneutrality of the crystal, the system spontaneously compensates for defects (cation vacancy defects) or undergoes charge transfer (charge compensation), synergistically forming strong metal-oxygen bonds in multi-metal components. The ingenious use of extreme temperature differences to induce lattice distortion is based on the principle that high temperatures provide sufficient energy for the long-range diffusion of metal ions in the lattice, allowing different types of ions to be evenly distributed, forming a uniform thermodynamically stable state. Rapid cooling disrupts the thermodynamically dominated process, transforming it into a kinetically controlled process. This timely suppression of long-range migration and rearrangement of metal ions freezes the transition of metal ions from different high-energy states to low-energy states, forming numerous oxygen vacancies and surface defects. This not only increases the number of active sites but also optimizes the electronic structure, promoting the adsorption and dissociation of water molecules. The rapid quenching process of this invention disrupts the equilibrium state of crystal growth in metal oxides, altering the integrity of the crystal cycle. Specifically, this manifests as the formation of metal ion vacancies and oxygen vacancies, resulting in delocalized electrons and electronic energy level defects. These defects are reflected in the crystal structure as changes in the coordination number of metal atoms and the appearance of dangling bonds. Ultimately, this leads to more effective overlap and charge transfer between the 2p orbitals of water molecules and the localized states of these delocalized electron orbitals or defects, optimizing the adsorption energy of the material for water molecules. Furthermore, it can weaken the chemical bonds of water molecules, providing a lower-energy pathway for the reaction, thereby significantly improving catalytic efficiency.

[0011] The alkaline water electrolysis catalyst of the present invention undergoes multiple impregnation-calcination-quenching processes, which can effectively solve the problem of catalyst coating peeling caused by local stress concentration, effectively prevent the dissolution and peeling of active components during long-term operation, improve the adhesion of the catalyst coating, and solve the problems of low catalytic activity, poor stability and high preparation cost in the prior art.

[0012] Preferably, the nickel substrate is nickel foam, nickel felt, nickel mesh, or nickel-plated stainless steel mesh.

[0013] Preferably, in step S1, the surface of the nickel substrate is sandblasted before cleaning. The sandblasting method is as follows: the nickel substrate is passed through a sandblasting material with a pressure of 0.1MPa to 0.5MPa at a speed of 5cm / s to 20cm / s. The sandblasting material is alumina, glass beads, or ceramic beads. The particle size of the sandblasting material is 60 mesh to 200 mesh.

[0014] Preferably, the cleaning solution used for cleaning in S1 includes an acid solution A with a mass fraction of 1% to 5% or an alkaline solution B with a mass fraction of 10% to 20%; the acid solution A is one or more of sulfuric acid aqueous solution, oxalic acid aqueous solution and hydrochloric acid aqueous solution; the alkaline solution B is sodium hydroxide aqueous solution and / or potassium hydroxide aqueous solution.

[0015] Preferably, the nickel salt in S2 is nickel sulfate, nickel chloride, nickel nitrate, or nickel acetate; the cobalt salt is cobalt sulfate, cobalt chloride, cobalt nitrate, or cobalt acetate; the ferrous salt is ferrous sulfate or ferrous chloride; the ferric salt is ferric sulfate, ferric chloride, or ferric nitrate; and the Ni in the precursor solution... 2+ The molar concentration is 0.1 mol / L to 0.5 mol / L; Co 2+ The molar concentration is 0.1 mol / L to 0.25 mol / L; Fe 2+ Or Fe 3+ The molar concentration is 0 mol / L to 0.1 mol / L.

[0016] Preferably, the dispersant in S2 is citric acid, sodium citrate, disodium ethylenediaminetetraacetate, or tartaric acid; the molar concentration of the dispersant in the precursor solution is 0.05 mol / L to 0.45 mol / L.

[0017] Preferably, the antioxidant in S2 is ascorbic acid, sodium ascorbate, or nano-carbon powder; the mass concentration of the antioxidant in the precursor solution is 0.2 g / L to 2 g / L.

[0018] Preferably, the number of times the impregnation-calcination-quenching process is carried out in S4 is 5 to 20 times; the coating thickness of the nickel-cobalt-iron alkaline water electrolysis catalyst based on the quenching process in S4 is 2 μm to 15 μm.

[0019] The present invention also provides the application of the nickel-cobalt-iron alkaline water electrolysis catalyst prepared by the above preparation method based on quenching process, characterized in that the nickel-cobalt-iron alkaline water electrolysis catalyst based on quenching process is used for water electrolysis catalysis.

[0020] Compared with the prior art, the present invention has the following advantages: 1. This invention utilizes the similar ionic radii of iron, cobalt, and nickel to synergistically form strong metal-oxygen bonds in multiple metal components. It cleverly employs extreme temperature differences to induce lattice distortion, creating numerous oxygen vacancies and surface defects. This not only increases the number of active sites but also optimizes the electronic structure, promoting the adsorption and dissociation of water molecules. The alkaline water electrolysis catalyst of this invention undergoes multiple impregnation-calcination-quenching processes, effectively solving the problem of catalyst coating detachment caused by localized stress concentration. It effectively prevents the dissolution and detachment of active components during long-term operation, enhances the adhesion of the catalyst coating, and addresses the problems of low catalytic activity, poor stability, and high preparation costs in existing technologies.

[0021] 2. The non-precious metal raw materials used in this invention are inexpensive, the process is simple to operate, and it is easy to scale up production, thus having great potential for promotion. The nickel-cobalt-iron ternary alkaline water electrolysis catalyst prepared by this invention based on the quenching process has high activity and strong binding force, and can effectively solve the problem of catalyst performance degradation.

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0023] Figure 1 This is an electron microscope image of the nickel-cobalt-iron ternary alkaline water electrolysis catalyst prepared by quenching process in Example 1 of the present invention.

[0024] Figure 2 This is a comparison chart of the operational stability curves of the catalysts prepared in Example 1 and the comparative example of the present invention when used for long-term water electrolysis.

[0025] Figure 3 This is a comparison of the ultrasonic shedding rate and the shedding rate after long-term operation of the catalysts prepared in Example 1 and the comparative example of the present invention. Detailed Implementation

[0026] Example 1 This embodiment describes a nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on a quenching process. The chemical formula of the quenching-process-based nickel-cobalt-iron ternary alkaline water electrolysis catalyst is Ni₂CoFe. 0.04 O 4.04 .

[0027] This embodiment also provides a method for preparing the above-mentioned nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on quenching process, the method being as follows: S1. Pretreatment of nickel substrate: The nickel substrate is a nickel mesh woven with 40 mesh, 0.19mm wire diameter, and plain weave. The surface of the nickel substrate is sandblasted and cleaned, and then dried at 80°C for 2 hours to obtain the pretreated nickel substrate. The sandblasting method is as follows: the nickel substrate is passed through a sandblasting material with a pressure of 0.2 MPa at a speed of 20 cm / s, and then the floating dust and powder on the surface of the substrate are blown away with compressed air; the sandblasting material is glass beads with a particle size of 80 mesh; The cleaning method is as follows: First, immerse the nickel substrate in a 1% sulfuric acid aqueous solution for 5 minutes, rinse it with deionized water, then immerse it in a 10% sodium hydroxide aqueous solution for 25 minutes, and rinse it with deionized water. S2. Preparation of precursor solution: The main salt (a mixture of nickel sulfate hexahydrate, cobalt chloride hexahydrate, and ferrous sulfate heptahydrate), dispersant (sodium citrate), and antioxidant (ascorbic acid) are added to deionized water and mixed evenly to obtain a precursor solution. Ni in the precursor solution 2+ The molar concentration is 0.5 mol / L, Co 2+ The molar concentration is 0.25 mol / L, Fe 2+ The molar concentration of the agent is 0.01 mol / L, the molar concentration of the dispersant is 0.05 mol / L, and the mass concentration of the antioxidant is 0.25 g / L. S3, Impregnation-calcination-quenching: S301, Impregnation: The pretreated nickel substrate obtained in S1 was immersed in the precursor solution obtained in S2 for 3 minutes, then removed and dried at 80°C for 2 hours to obtain the dried substrate. S302, calcination: The dried substrate obtained in S301 was heated from room temperature to 650℃ at a heating rate of 20℃ / min and calcined at a constant temperature for 1 hour to obtain the calcined substrate. S303, Quenching: The calcined substrate obtained in S302 was rapidly immersed in an ice-water mixture at 0°C for quenching, washed with deionized water, and dried to obtain the catalyst precursor. S4. Repeat the impregnation-calcination-quenching process in step S3 15 times to obtain a Ni2CoFe ternary alkaline water electrolysis catalyst with a coating thickness of 12μm based on the quenching process. 0.04 O 4.04 .

[0028] like Figure 1As shown, the coating on the surface of the material is uniformly distributed, and the low-temperature structure inhibits the formation of large particles, with no obvious traces of excessive crystal growth.

[0029] This embodiment also provides the application of the nickel-cobalt-iron ternary alkaline water electrolysis catalyst prepared by the above preparation method, which is used for water electrolysis catalysis.

[0030] Comparative Example 1 This comparative example describes a nickel-cobalt-iron ternary alkaline water electrolysis catalyst, the chemical formula of which is Ni₂CoFe. 0.04 O 4.04 .

[0031] This comparative example also provides a method for preparing the above-mentioned nickel-cobalt-iron ternary alkaline water electrolysis catalyst, the method being as follows: S1. Pretreatment of nickel substrate: Same as step S1 in Example 1; S2. Preparation of precursor solution: Same as step S2 in Example 1; S3, Impregnation-calcination: S301, Impregnation: Same as step S301 in Example 1; S302, calcination: The dried substrate obtained in S301 was heated from room temperature to 650℃ at a heating rate of 20℃ / min, calcined at a constant temperature for 1 hour, and then naturally cooled to room temperature to obtain the calcined substrate. S4. Repeat the impregnation-calcination process in step S3 15 times to obtain a Ni2CoFe ternary alkaline water electrolysis catalyst with a coating thickness of 11.5 μm based on a quenching process. 0.04 O 4.04 .

[0032] For overpotential and ultrasonic shedding rate testing of materials, refer to National Standard GB / T45092-2024, Parts VI and V. The weight loss rate after operation is [not specified] for a 3cm × 3cm electrode at 3000 A / m. 2 The weight difference of the electrode before and after testing at current density for 268 hours is the percentage of the electrode's weight before testing.

[0033] like Figure 2 As shown, the nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni2CoFe prepared in Example 1 0.04 O 4.04 As an electrode material, at 3000 A / m 2 The hydrogen evolution and oxygen evolution overpotentials at the current density were 433 mV and 587 mV, respectively, which were 199 mV and 103 mV lower than those of the control group under the same conditions, indicating that the quenching process improved the activity of the three-way catalyst in Example 1.

[0034] like Figure 3 As shown, the nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni2CoFe prepared in Example 1 0.04 O 4.04 The catalyst was used as both the cathode and anode, at 3000 A / m 2 Electrolysis of water at current density for 268 hours also showed excellent stability, with the voltage after stable operation being 90mV lower than that of the control group (Table 1).

[0035] As shown in Table 1, the nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni2CoFe prepared in Example 1 0.04 O 4.04 As an electrode material, it operates stably at 1.90V, and after 268 hours of water electrolysis, its weight loss rate is only 0.27%. Furthermore, after 1 hour of ultrasonication at a frequency of 40kHz, Ni₂CoFe... 0.04 O 4.04 The catalyst ultrasonic shedding rate was 0.74%, which was also much lower than that of Comparative Example 1 (1.31%), indicating that the catalyst of Comparative Example 1 had better binding force.

[0036] Table 1. Comparison of catalyst ultrasonic shedding rate and long-term operation shedding rate in Example 1 and Comparative Example 1 Example 2 This embodiment describes a nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on a quenching process. The chemical formula of the catalyst is NiCoFe. 0.4 O 3.4 .

[0037] This embodiment also provides a method for preparing the above-mentioned nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on quenching process, the method being as follows: S1. Pretreatment of nickel substrate: The nickel substrate is foamed nickel, which does not require sandblasting; The nickel substrate was cleaned and dried at 80°C for 2 hours to obtain the pretreated nickel substrate. The cleaning method is as follows: First, immerse the nickel substrate in one or more hydrochloric acid solutions with a mass fraction of 1.5% for 1 minute, rinse it with deionized water, and then immerse it in a sodium hydroxide solution with a mass fraction of 20% for 10 minutes, and rinse it with deionized water. S2. Preparation of precursor solution: The main salt (a mixture of nickel acetate tetrahydrate, cobalt sulfate heptahydrate and ferric chloride hexahydrate), dispersant (citric acid) and antioxidant (nano-carbon powder with an average particle size of 30 nm) were added to deionized water and mixed evenly to obtain a precursor solution. Ni in the precursor solution 2+ The molar concentration of Co is 0.25 mol / L. 2+ The molar concentration is 0.25 mol / L, Fe 3 + The molar concentration of the agent is 0.1 mol / L, the molar concentration of the dispersant is 0.45 mol / L, and the mass concentration of the antioxidant is 0.2 g / L. S3, Impregnation-calcination-quenching: S301, Impregnation: The pretreated nickel substrate obtained in S1 is immersed in the precursor solution obtained in S2 for 10 min, taken out, and dried at 80℃ for 2 h to obtain the dried substrate. S302, calcination: The dried substrate obtained in S301 was heated from room temperature to 300℃ at a heating rate of 5℃ / min and calcined at a constant temperature for 0.5h to obtain the calcined substrate. S303, Quenching: The calcined substrate obtained in S302 was rapidly immersed in an ice-water mixture at 0°C for quenching, washed with deionized water, and dried at 80°C for 2 hours to obtain the catalyst precursor. S4. Repeat the impregnation-calcination-quenching process in step S3 five times to obtain a nickel-cobalt-iron ternary alkaline water electrolysis catalyst NiCoFe with a coating thickness of 2μm based on the quenching process. 0.4 O 3.4 .

[0038] The nickel-cobalt-iron ternary alkaline water electrolysis catalyst NiCoFe prepared in this embodiment is based on a quenching process. 0.4 O 3.4 Used for water electrolysis catalysis.

[0039] The nickel-cobalt-iron ternary alkaline water electrolysis catalyst NiCoFe prepared in this embodiment 0.4 O 3.4 As an electrode material, it operates at a stable voltage of 1.94V and has a weight loss rate of only 0.66% after 268 hours of water electrolysis. Under ultrasonic conditions of 40kHz for 1 hour, the ultrasonic shedding rate is 0.89%, demonstrating excellent bonding strength.

[0040] Example 3 This embodiment describes a nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on a quenching process. The chemical formula of the nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on the quenching process is Ni. 0.4 Co 0.8 Fe 0.06 O 2.26 .

[0041] This embodiment also provides a method for preparing the above-mentioned nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on quenching process, the method being as follows: S1. Pretreatment of nickel substrate: The nickel substrate is nickel felt, which does not require sandblasting; The nickel substrate was cleaned and dried at 80°C for 2 hours to obtain the pretreated nickel substrate. The cleaning method is as follows: Immerse the nickel substrate in a mixture of 10% sodium hydroxide aqueous solution and 10% potassium hydroxide aqueous solution (volume ratio 1:1) for 10 minutes, and then rinse it with deionized water. S2. Preparation of precursor solution: The main salt (a mixture of nickel chloride hexahydrate, cobalt acetate tetrahydrate and ferrous sulfate heptahydrate), dispersant (tartaric acid) and antioxidant (ascorbic acid) are added to deionized water and mixed evenly to obtain a precursor solution. Ni in the precursor solution 2+ The molar concentration of Co is 0.1 mol / L. 2+ The molar concentration is 0.2 mol / L, Fe 2+ The molar concentration of the agent is 0.015 mol / L, the molar concentration of the dispersant is 0.05 mol / L, and the mass concentration of the antioxidant is 0.2 g / L. S3, Impregnation-calcination-quenching: S301, Impregnation: The pretreated nickel substrate obtained in S1 was immersed in the precursor solution obtained in S2 for 5 minutes, then removed and dried at 80°C for 2 hours to obtain the dried substrate. S302, calcination: The dried substrate obtained in S301 was heated from room temperature to 350℃ at a heating rate of 5℃ / min and calcined at a constant temperature for 0.5h to obtain the calcined substrate. S303, Quenching: The calcined substrate obtained in S302 was rapidly immersed in an ice-water mixture at 0°C for quenching, washed with deionized water, and dried at 80°C for 2 hours to obtain the catalyst precursor. S4. Repeat the impregnation-calcination-quenching process in step S3 20 times to obtain a nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni based on the quenching process with a coating thickness of 15μm. 0.4 Co 0.8 Fe 0.06 O 2.26 .

[0042] The nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni prepared in this embodiment is based on a quenching process. 0.4 Co 0.8 Fe 0.06 O 2.26 Used for water electrolysis catalysis.

[0043] The nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni prepared in this embodiment 0.4 Co 0.8 Fe 0.06 O 2.26 As an electrode material, it operates at a stable voltage of 1.85V and has a weight loss rate of only 0.52% after 268 hours of water electrolysis. Under ultrasonic conditions of 40kHz for 1 hour, the ultrasonic shedding rate is 1.27%, demonstrating excellent bonding strength.

[0044] Example 4 This embodiment describes a nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on a quenching process. The chemical formula of the nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on the quenching process is Ni. 1.25 Co 0.75 Fe 0.5 O 3.5 .

[0045] This embodiment also provides a method for preparing the above-mentioned nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on quenching process, the method being as follows: S1. Pretreatment of nickel substrate: The nickel substrate is a stainless steel mesh with a 46-mesh diameter, 0.25mm wire diameter, and twill weave, plated with nickel. The nickel plating layer is 120μm thick. The surface of the nickel substrate is sandblasted and cleaned, and then dried at 80°C for 2 hours to obtain the pretreated nickel substrate. The sandblasting method is as follows: the nickel substrate is passed through a sandblasting material with a pressure of 0.1 MPa at a speed of 5 cm / s, and then the floating dust and powder on the surface of the substrate are blown away with compressed air; the sandblasting material is glass beads with a particle size of 200 mesh; The cleaning method is as follows: First, immerse the nickel substrate in a 15% potassium hydroxide aqueous solution for 10 minutes, and then rinse it with deionized water. S2. Preparation of precursor solution: The main salt (a mixture of nickel nitrate hexahydrate, cobalt nitrate hexahydrate, and ferric nitrate nonahydrate), dispersant (sodium citrate), and antioxidant (ascorbic acid) are added to deionized water and mixed evenly to obtain a precursor solution. In this embodiment, ferric nitrate nonahydrate can also be ferric sulfate pentahydrate; Ni in the precursor solution 2+ The molar concentration is 0.35 mol / L, Co 2+The molar concentration is 0.15 mol / L, Fe 3+ The molar concentration of the agent is 0.1 mol / L, the molar concentration of the dispersant is 0.22 mol / L, and the mass concentration of the antioxidant is 2 g / L. S3, Impregnation-calcination-quenching: S301, Impregnation: The pretreated nickel substrate obtained in S1 is immersed in the precursor solution obtained in S2 for 2 minutes, then removed and dried at 80°C for 2 hours to obtain the dried substrate. S302, calcination: The dried substrate obtained in S301 was heated from room temperature to 480℃ at a heating rate of 20℃ / min and calcined at a constant temperature for 0.5h to obtain the calcined substrate. S303, Quenching: The calcined substrate obtained in S302 was rapidly immersed in an ice-water mixture at 0°C for quenching, washed with deionized water, and dried at 80°C for 2 hours to obtain the catalyst precursor. S4. Repeat the impregnation-calcination-quenching process in step S3 10 times to obtain a nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni based on the quenching process with a coating thickness of 8μm. 1.25 Co 0.75 Fe 0.5 O 3.5 .

[0046] The nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni prepared in this embodiment is based on a quenching process. 1.25 Co 0.75 Fe 0.5 O 3.5 Used for water electrolysis catalysis.

[0047] The nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni prepared in this embodiment 1.25 Co 0.75 Fe 0.5 O 3.5 As an electrode material, it has a stable operating voltage of 1.94V and a weight loss rate of only 0.38% after 268 hours of water electrolysis. Under ultrasonic conditions of 40kHz for 1 hour, the ultrasonic shedding rate is 1.17%, demonstrating excellent bonding strength.

[0048] Example 5 This embodiment describes a nickel-cobalt binary alkaline water electrolysis catalyst based on a quenching process. The chemical formula of the nickel-cobalt binary alkaline water electrolysis catalyst based on the quenching process is Ni. 1.8 Co 0.8 O 3.6 .

[0049] This embodiment also provides a method for preparing the above-mentioned nickel-cobalt binary alkaline water electrolysis catalyst based on quenching process, the method being as follows: S1. Pretreatment of nickel substrate: The nickel substrate is a nickel mesh woven with 46 mesh, 0.25mm wire diameter, and twill weave. The surface of the nickel substrate is sandblasted and cleaned, and then dried at 80°C for 2 hours to obtain the pretreated nickel substrate. The sandblasting method is as follows: the nickel substrate is passed through a sandblasting material with a pressure of 0.5 MPa at a speed of 17 cm / s, and then the floating dust and powder on the surface of the substrate are blown away with compressed air; the sandblasting material is white alumina with a particle size of 80 mesh. The cleaning method is as follows: First, immerse the nickel substrate in a 1% oxalic acid aqueous solution and a 4% hydrochloric acid aqueous solution with a volume ratio of 1:1 for 25 minutes, and then rinse it with deionized water. S2. Preparation of precursor solution: The main salt (a mixture of nickel sulfate hexahydrate and cobalt chloride hexahydrate), dispersant (disodium ethylenediaminetetraacetate) and antioxidant (nanocarbon powder with an average particle size of 30 nm) were added to deionized water and mixed evenly to obtain a precursor solution. Ni in the precursor solution 2+ The molar concentration is 0.45 mol / L, Co 2+ The molar concentration of the agent is 0.2 mol / L, the molar concentration of the dispersant is 0.1 mol / L, and the mass concentration of the antioxidant is 1 g / L. S3, Impregnation-calcination-quenching: S301, Impregnation: The pretreated nickel substrate obtained in S1 was immersed in the precursor solution obtained in S2 for 3 minutes, then removed and dried at 80°C for 2 hours to obtain the dried substrate. S302, calcination: The dried substrate obtained in S301 was heated from room temperature to 750℃ at a heating rate of 20℃ / min and calcined at a constant temperature for 0.5h to obtain the calcined substrate. S303, Quenching: The calcined substrate obtained in S302 was rapidly immersed in liquid nitrogen at a temperature of -196℃ for quenching, washed with deionized water, and dried at a temperature of 80℃ for 2 hours to obtain the catalyst precursor. S4. Repeat the impregnation-calcination-quenching process in step S3 12 times to obtain a nickel-cobalt binary alkaline water electrolysis catalyst Ni based on the quenching process with a coating thickness of 9.5 μm. 1.8 Co 0.8 O 3.6 .

[0050] The nickel-cobalt binary alkaline water electrolysis catalyst Ni prepared in this embodiment is based on a quenching process. 1.8 Co 0.8 O 3.6 Used for water electrolysis catalysis.

[0051] The nickel-cobalt binary alkaline water electrolysis catalyst Ni prepared in this embodiment 1.8 Co 0.8 O 3.6 As an electrode material, it has a stable operating voltage of 1.91V and a weight loss rate of only 0.41% after 268 hours of water electrolysis. Under ultrasonic conditions of 40kHz for 1 hour, the ultrasonic shedding rate is 0.52%, demonstrating excellent bonding strength.

[0052] According to the method of this embodiment, nickel-iron binary alkaline water electrolysis catalyst and cobalt-iron binary alkaline water electrolysis catalyst based on quenching process can also be prepared.

[0053] Example 6 The nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on the quenching process in this embodiment has the chemical formula Ni2CoFeO5.

[0054] This embodiment also provides a method for preparing the above-mentioned nickel-cobalt-iron ternary alkaline water electrolysis catalyst based on quenching process, the method being as follows: S1. Pretreatment of nickel substrate: The nickel substrate is a nickel mesh woven with 46 mesh, 0.25mm wire diameter, and twill weave. The surface of the nickel substrate is sandblasted and cleaned, and then dried at 80°C for 2 hours to obtain the pretreated nickel substrate. The sandblasting method is as follows: the nickel substrate is passed through a sandblasting material with a pressure of 0.4 MPa at a speed of 10 cm / s, and then the floating dust and powder on the surface of the substrate are blown away with compressed air; the sandblasting material is ceramic beads with a particle size of 60 mesh. The cleaning method is as follows: First, immerse the nickel substrate in a 5% (w / w) oxalic acid aqueous solution for 10 minutes, and then rinse it clean with deionized water. S2. Preparation of precursor solution: The main salt (a mixture of nickel sulfate hexahydrate, cobalt sulfate heptahydrate, and ferrous sulfate heptahydrate), dispersant (sodium citrate), and antioxidant (ascorbic acid) are added to deionized water and mixed evenly to obtain a precursor solution. In this embodiment, ferrous sulfate heptahydrate can also be ferrous chloride tetrahydrate; Ni in the precursor solution 2+ The molar concentration is 0.2 mol / L, Co2+ The molar concentration is 0.1 mol / L, Fe 2+ The molar concentration of the agent is 0.1 mol / L, the molar concentration of the dispersant is 0.05 mol / L, and the mass concentration of the antioxidant is 2 g / L. S3, Impregnation-calcination-quenching: S301, Impregnation: The pretreated nickel substrate obtained in S1 was immersed in the precursor solution obtained in S2 for 6 minutes, then removed and dried at 80°C for 2 hours to obtain the dried substrate. S302, calcination: The dried substrate obtained in S301 was heated from room temperature to 550℃ at a heating rate of 10℃ / min and calcined at a constant temperature for 1 hour to obtain the calcined substrate. S303, Quenching: The calcined substrate obtained in S302 was rapidly immersed in liquid nitrogen at a temperature of -196℃ for quenching, washed with deionized water, and dried at a temperature of 80℃ for 2 hours to obtain the catalyst precursor. S4. Repeat the impregnation-calcination-quenching process in step S3 20 times to obtain a nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni2CoFeO5 with a coating thickness of 15μm based on the quenching process.

[0055] The nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni2CoFeO5 prepared in this embodiment based on quenching process is used for water electrolysis catalysis.

[0056] The nickel-cobalt-iron ternary alkaline water electrolysis catalyst Ni2CoFeO5 prepared in this embodiment, used as the electrode material, has a stable operating voltage of 1.88V. After 268 hours of water electrolysis, the weight loss rate is only 0.43%. Under ultrasonic conditions of 40kHz for 1 hour, the ultrasonic shedding rate is 0.89%, demonstrating excellent binding force.

[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive essence shall still fall within the protection scope of the present invention.

Claims

1. A nickel-cobalt-iron alkaline water electrolysis catalyst based on a quenching process, characterized in that, The general chemical formula of the nickel-cobalt-iron alkaline water electrolysis catalyst based on the quenching process is Ni x Co y Fe z O x+y+z+1 , where 0 < x + y + z ≤ 4, and 0 ≤ x ≤ 2, 0 ≤ y ≤ 1, 0 ≤ z ≤ 1.

2. A method for preparing the nickel-cobalt-iron alkaline water electrolysis catalyst based on the quenching process as described in claim 1, characterized in that, The method is as follows: S1. Pretreatment of nickel substrate: After cleaning and drying the nickel substrate, a pretreated nickel substrate is obtained. S2. Preparation of precursor solution: The main salt, dispersant, and antioxidant were added to deionized water and mixed thoroughly to obtain the precursor solution. The main salt is a mixture of nickel salt, cobalt salt and ferrous salt or a mixture of nickel salt, cobalt salt and ferrous salt; S3, Impregnation-calcination-quenching: S301, Impregnation: The pretreated nickel substrate obtained in S1 is immersed in the precursor solution obtained in S2 for 2 min to 10 min, then removed and dried to obtain the dried substrate. S302, calcination: The dried substrate obtained in S301 was heated from room temperature to 300℃~750℃ at a heating rate of 5℃ / min~20℃ / min and calcined at a constant temperature for 0.5h~1h to obtain the calcined substrate. S303, Quenching: The calcined substrate obtained from S302 is immersed in an ice-water mixture or liquid nitrogen for quenching, washed with deionized water, and dried to obtain the catalyst precursor. S4. Repeat the impregnation-calcination-quenching process in step S3 multiple times to obtain a nickel-cobalt-iron alkaline water electrolysis catalyst based on the quenching process.

3. The method according to claim 2, characterized in that, The nickel substrate is nickel foam, nickel felt, nickel mesh, or nickel-plated stainless steel mesh.

4. The method according to claim 2, characterized in that, In step S1, before cleaning, the surface of the nickel substrate is sandblasted. The sandblasting method is as follows: the nickel substrate is passed through a sandblasting material with a pressure of 0.1MPa to 0.5MPa at a speed of 5cm / s to 20cm / s. The sandblasting material is alumina, glass beads, or ceramic beads. The particle size of the sandblasting material is 60 mesh to 200 mesh.

5. The method according to claim 2, characterized in that, The cleaning solution used in S1 includes an acid solution A with a mass fraction of 1% to 5% or an alkaline solution B with a mass fraction of 10% to 20%; the acid solution A is one or more of sulfuric acid aqueous solution, oxalic acid aqueous solution and hydrochloric acid aqueous solution; the alkaline solution B is sodium hydroxide aqueous solution and / or potassium hydroxide aqueous solution.

6. The method according to claim 2, characterized in that, The nickel salt in S2 is nickel sulfate, nickel chloride, nickel nitrate, or nickel acetate; the cobalt salt is cobalt sulfate, cobalt chloride, cobalt nitrate, or cobalt acetate; the ferrous salt is ferrous sulfate or ferrous chloride; the ferric salt is ferric sulfate, ferric chloride, or ferric nitrate; and the Ni in the precursor solution... 2+ The molar concentration is 0.1 mol / L to 0.5 mol / L; Co 2+ The molar concentration is 0.1 mol / L to 0.25 mol / L; Fe 2+ Or Fe 3+ The molar concentration is 0 mol / L to 0.1 mol / L.

7. The method according to claim 2, characterized in that, The dispersant in S2 is citric acid, sodium citrate, disodium ethylenediaminetetraacetate, or tartaric acid; the molar concentration of the dispersant in the precursor solution is 0.05 mol / L to 0.45 mol / L.

8. The method according to claim 2, characterized in that, The antioxidant mentioned in S2 is ascorbic acid, sodium ascorbate, or nano-carbon powder; the mass concentration of the antioxidant in the precursor solution is 0.2 g / L to 2 g / L.

9. The method according to claim 2, characterized in that, The number of times the impregnation-calcination-quenching process is carried out in S4 is 5 to 20 times; the coating thickness of the nickel-cobalt-iron alkaline water electrolysis catalyst based on the quenching process in S4 is 2 μm to 15 μm.

10. An application of a nickel-cobalt-iron alkaline water electrolysis catalyst prepared by the preparation method according to any one of claims 2-9, characterized in that, The nickel-cobalt-iron alkaline water electrolysis catalyst based on quenching process is used for water electrolysis catalysis.

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