Calcination-based preparation method of copper-iron alloy type catalyst for hydrogen production by electrolysis of water

Abstract

The invention discloses a preparation method of a calcined copper-iron alloy type catalyst for hydrogen production by electrolysis of water, which has the advantages that a synergistic effect is generated through interaction of various metal elements, the hydrogen evolution activity, stability and tolerance of the catalyst in high-corrosivity high-concentration alkaline electrolyte are improved, the dependence on single noble metal is reduced, and the hydrogen production efficiency is improved. The cost is further reduced, and the utilization efficiency of resources is improved.

Description

Technical Field

[0001] The invention relates to the technical field of water electrolysis hydrogen production, and in particular to a method for preparing a calcined copper-iron alloy type water electrolysis hydrogen production catalyst. Background Art

[0002] As the global demand for clean energy increases, especially in the context of addressing climate change and reducing greenhouse gas emissions, hydrogen energy as a clean energy carrier has received widespread attention. The advancement of water electrolysis technology has gradually reduced the cost of hydrogen production, especially in the research and development of electrolytes and electrode materials. Alkaline water electrolysis technology has become a research hotspot with its high efficiency and low cost.

[0003] Although alkaline water electrolysis technology has many advantages, there are still some problems in practical applications. The cost of water electrolysis has been reduced, but it is still not economical compared with traditional hydrogen production methods (such as natural gas reforming), especially in areas with high electricity costs. At the same time, the corrosion resistance and durability of electrode materials remain a challenge. Many electrodes will experience performance degradation after long-term operation, affecting the overall efficiency. Therefore, in the process of promoting the development of alkaline water electrolysis technology, the following challenges are faced: it is necessary to continuously develop new electrode materials and electrolytes to improve electrolysis efficiency and reduce costs, while improving the durability of equipment. Despite the challenges, the development of alkaline water electrolysis technology also contains many opportunities. In order to solve the above challenges, it is necessary to design and develop low-cost alloy catalysts suitable for high-concentration alkaline water electrolysis. Summary of the invention

[0004] In order to solve the above technical problems, a technical solution adopted by the present invention is: Provided is a method for preparing a calcined copper-iron alloy type water electrolysis hydrogen production catalyst, the steps comprising: (1) Preparation of precursor (1.1) Prepare a solution by mixing copper salt, iron salt and deionized water, so that the concentration of iron salt in the solution is 0.1 mol / L~0.5 mol / L, the concentration of copper salt is 0.3 mol / L~3 mol / L, and the molar ratio of iron to copper is 1:3~6; (1.2) adding sodium hydroxide to the above solution and mixing and stirring to obtain a mixed solution, wherein the concentration of sodium hydroxide in the mixed solution is 0.2-2 mol / L; (1.3) immersing the nickel substrate in the mixed solution and performing ultrasound treatment, taking out the treated nickel substrate and drying it; (1.4) The dried nickel substrate is transferred to a muffle furnace and calcined at high temperature for 3 to 5 hours at a temperature of 300 to 900°C. After the reaction cools to room temperature, a precursor loaded on the nickel mesh is obtained; (2) Preparation of copper-iron alloy catalyst on precursor (2.1) Disperse the iron salt in water and stir evenly to obtain an iron salt solution, the concentration of which is 0.3 mol / L~2 mol / L; (2.2) After the precursor is placed in the iron salt solution, it is all transferred to a vacuum drying oven for drying. After the solvent is evaporated, the dried material is placed in a tubular furnace and calcined under a protective atmosphere before being taken out. The calcination temperature is 400~600℃ and the calcination time is 2~5h to obtain a double-sided supported copper-iron alloy catalyst.

[0005] In a preferred embodiment of the present invention, in step (1.1), the iron salt includes one or more of ferric chloride, ferric nitrate, ferric sulfate, ferric acetate, and ferric acetylacetonate.

[0006] In a preferred embodiment of the present invention, in step (1.1), the copper salt includes one or more of copper chloride, copper nitrate, copper sulfate, and copper acetate.

[0007] In a preferred embodiment of the present invention, in step (1.1), the amount of deionized water is 200-1000 mL.

[0008] In a preferred embodiment of the present invention, the nickel substrate includes a nickel mesh, a nickel plate or a titanium film.

[0009] In a preferred embodiment of the present invention, the ultrasonic time is 10-30 minutes, and the ultrasonic power is 300-500W.

[0010] In a preferred embodiment of the present invention, in step (2.1), the iron salt includes one or more of ferric chloride, ferric nitrate, ferric sulfate, ferric acetate, and ferric acetylacetonate.

[0011] In a preferred embodiment of the present invention, in step (2.1), the amount of deionized water is 30 mL to 100 mL.

[0012] In a preferred embodiment of the present invention, the calcination temperature in the tubular furnace is 200-900°C.

[0013] In a preferred embodiment of the present invention, the protective atmosphere includes one or more of nitrogen, argon, and helium.

[0014] The beneficial effects of the present invention are: a synergistic effect is produced through the interaction of multiple metal elements, thereby improving the hydrogen evolution activity, stability and tolerance of the catalyst in a highly corrosive and high-concentration alkaline electrolyte, reducing dependence on a single precious metal, further reducing costs and improving resource utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which: Figure 1 is a comparison chart of HER performance of CuFe catalyst in Example 1 of the present invention; Figure 2 This is a comparison chart of the OER performance of the CuFe catalyst in Example 1 of the present invention; Figure 3 This is a graph showing the stability test of the CuFe catalyst in Example 1 of the present invention. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] See also Figure 1-3 , the embodiment of the present invention includes: A method for preparing a calcined copper-iron alloy type water electrolysis hydrogen production catalyst, wherein a CuFe metal catalyst is loaded on a nickel substrate, and the steps include: (1) Preparation of precursor (1.1) Take a certain amount of copper salt and iron salt and deionized water to prepare a solution, so that the concentration of iron salt in the solution is 0.1 mol / L~0.5 mol / L, the concentration of copper salt is 0.3 mol / L~3 mol / L, and the molar ratio of iron to copper is 1:3~6.

[0018] Further preferably, the iron salt includes one or more of ferric chloride, ferric nitrate, ferric sulfate, ferric acetate, and ferric acetylacetonate.

[0019] Further preferably, the copper salt includes one or more of copper chloride, copper nitrate, copper sulfate and copper acetate.

[0020] Further preferably, in step (1.1), the amount of deionized water is 200-1000 mL.

[0021] (1.2) Sodium hydroxide is added to the above solution and mixed with stirring to obtain a mixed solution, wherein the concentration of sodium hydroxide in the mixed solution is 0.2~2 mol / L.

[0022] (1.3) Immerse the nickel substrate in the mixed solution and perform ultrasound treatment. Take out the treated nickel substrate and dry it.

[0023] Further preferably, the nickel substrate includes a nickel mesh, a nickel plate or a titanium film.

[0024] More preferably, the ultrasonic time is 10-30 minutes, and the ultrasonic power is 300-500W.

[0025] (1.4) The dried nickel substrate is transferred to a porcelain boat and placed in a muffle furnace for high-temperature calcination for 3 to 5 hours. After the reaction cools to room temperature, a precursor loaded on the nickel mesh is obtained.

[0026] More preferably, the calcination temperature of the muffle furnace is 300-900°C.

[0027] (2) Preparation of copper-iron alloy catalyst on precursor (2.1) Weigh iron salt, disperse it in water and stir it evenly to obtain an iron salt solution with a concentration of 0.3 mol / L~2 mol / L; (2.2) The precursor is placed in an iron salt solution and then placed in a vacuum drying oven for drying. After the solvent is evaporated, the dried material is placed in a tubular furnace and calcined under a protective atmosphere, and then taken out to obtain a double-sided supported copper-iron alloy catalyst.

[0028] Further preferably, the iron salt includes one or more of ferric chloride, ferric nitrate, ferric sulfate, ferric acetate, and ferric acetylacetonate.

[0029] More preferably, the amount of deionized water is 30 mL to 100 mL.

[0030] More preferably, the calcination temperature in the tubular furnace is 200-900°C.

[0031] More preferably, the protective atmosphere includes one or more of nitrogen, argon and helium.

[0032] The present invention uses a porous woven nickel mesh as an electrode substrate, prepares a Cu-based bimetallic catalyst by calcining and loading, and successfully develops a catalyst membrane electrode with high efficiency and high stability. Selecting Cu as the catalyst active metal can show high stability in alkaline water electrolysis reactions, and can significantly reduce the cost of the catalyst relative to precious metal catalysts. At the same time, in order to further improve the performance and stability of the catalyst, the cheapest metal element iron is introduced as the second component, and a CuFe bimetallic catalyst system is developed at the same time. Since the charge transfer between the metals is conducive to changing the electronic structure of Cu, the catalytic activity and stability of the catalyst are improved, so as to achieve the development of an efficient and highly stable alkaline electrolysis hydrogen production HER catalyst. Example

[0033] 1) A method for preparing a calcined copper-iron alloy type water electrolysis hydrogen production catalyst, comprising the following steps: Take 0.3 mol of copper chloride and 0.1 mol of ferric chloride, dissolve them in 1 L of deionized water, stir evenly, then add 0.3 mol of NaOH, stir evenly, then add the nickel mesh substrate, and take it out after ultrasonic treatment for 20 min; place the nickel mesh in an oven at 60 °C to dry, take out the dried sample and place it in a muffle furnace, calcine it at 300 °C for 60 minutes in an air atmosphere, and the taken out sample is a CuFe alloy precursor.

[0034] The CuFe alloy precursor was immersed in 0.3 mol / L, 100 mL ferric chloride solution, and then all were transferred to a drying oven to evaporate the solvent. The remaining items were placed in a tube furnace at 10 °C min -1 The catalyst was heated at a rate of 100 °C and calcined at 600 °C for 1 h in a nitrogen atmosphere and then cooled to room temperature. The prepared catalyst was taken out to obtain the CuFe / Ni catalyst.

[0035] 2) Electrochemical testing The electrocatalytic hydrogen evolution performance of the prepared copper-iron alloy catalyst was tested by an electrochemical workstation using a three-electrode system. The CuFe / Ni catalyst obtained in step 1) was used as the working electrode, the Hg / HgO electrode was used as the reference electrode, the Pt / C was used as the counter electrode, the electrolyte was 1 mol / L KOH, and the linear sweep voltammetry method was used for the test at a scan rate of 5 mV / s.

[0036] The test results are as follows Figure 1 As shown, the CuFe alloy catalyst has a -2 Under the current density, the potential is -1.61 V, which is better than that of the single metal Fe catalyst, proving that the prepared CuFe catalyst has better electrochemical performance in alkaline solution.

[0037] The stability test was carried out in 1 mol / L KOH. The CuFe alloy catalyst could -2 It can run stably for 3000 h under high current density, which provides a new idea for the design and preparation of high-activity, low-cost alloy hydrogen evolution catalysts that are stable under large alkaline currents, and can significantly reduce the cost of the catalyst. It provides a new idea for bimetallic hydrogen evolution catalysts that are stable under large currents in alkaline environments and has broad application prospects. Example

[0038] According to the method of Example 1, except that the amounts of cupric chloride and ferric chloride added in step 1) are changed to 0.5 mol and 1 mol, and the rest are the same as in Example 1, a copper-iron alloy catalyst suitable for high-concentration alkaline water electrolysis is obtained. Example

[0039] According to the method of Example 1, except that the copper chloride added in step 1) is changed to cobalt chloride, and the rest is the same as Example 1, a copper-iron alloy catalyst suitable for high-concentration alkaline water electrolysis is obtained.

[0040] The beneficial effects of the preparation method of the calcined copper-iron alloy type water electrolysis hydrogen production catalyst of the present invention are: 1. The present invention has significant energy efficiency, and the formation of the alloy structure further optimizes the surface atomic structure and electronic structure of the catalyst, thereby being more conducive to the hydrogen and oxygen evolution reactions; 2. Alloy catalysts are suitable for high-concentration alkaline electrolytes. Multiple metal elements interact with each other to produce a synergistic effect, which improves the hydrogen evolution activity, stability and tolerance (corrosion resistance) of the catalyst in highly corrosive high-concentration alkaline electrolytes. At the same time, it can also reduce dependence on a single precious metal, further reduce costs and improve resource utilization efficiency.

[0041] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing a calcined copper-iron alloy type water electrolysis hydrogen production catalyst, characterized in that the steps include: (1) Preparation of precursor (1.1) Prepare a solution by mixing copper salt, iron salt and deionized water, so that the concentration of iron salt in the solution is 0.1 mol / L~0.5 mol / L, the concentration of copper salt is 0.3 mol / L~3 mol / L, and the molar ratio of iron to copper is 1:3~6; (1.2) adding sodium hydroxide to the above solution and mixing and stirring to obtain a mixed solution, wherein the concentration of sodium hydroxide in the mixed solution is 0.2-2 mol / L; (1.3) immersing the nickel substrate in the mixed solution and performing ultrasound treatment, taking out the treated nickel substrate and drying it; (1.4) The dried nickel substrate is transferred to a muffle furnace and calcined at a high temperature of 300-900°C for 3-5 hours. After the reaction cools to room temperature, a precursor loaded on the nickel mesh is obtained. (2) Preparation of copper-iron alloy catalyst on precursor (2.1) Disperse the iron salt in water and stir evenly to obtain an iron salt solution, the concentration of which is 0.3 mol / L~2 mol / L; (2.2) After the precursor is placed in the iron salt solution, it is all transferred to a vacuum drying oven for drying. After the solvent is evaporated, the dried material is placed in a tubular furnace and calcined under a protective atmosphere before being taken out. The calcination temperature is 400-600°C and the calcination time is 2-5 hours. After the calcination, a double-sided copper-iron alloy catalyst is obtained.

2. The method for preparing a calcined copper-iron alloy-type water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In step (1.1), the iron salt includes one or more of ferric chloride, ferric nitrate, ferric sulfate, ferric acetate, and ferric acetylacetonate.

3. The method for preparing a calcined copper-iron alloy-type water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In step (1.1), the copper salt includes one or more of copper chloride, copper nitrate, copper sulfate, and copper acetate.

4. The method for preparing a calcined copper-iron alloy-type water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In step (1.1), the amount of deionized water is 200~1000 mL.

5. The method for preparing a calcined copper-iron alloy-type water electrolysis hydrogen production catalyst according to claim 1, characterized in that: The nickel substrate includes a nickel mesh, a nickel plate or a titanium film.

6. The method for preparing a calcined copper-iron alloy-type water electrolysis hydrogen production catalyst according to claim 1, characterized in that: The ultrasonic time is 10~30 minutes, and the ultrasonic power is 300~500W.

7. The method for preparing a calcined copper-iron alloy-type water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In step (2.1), the iron salt includes one or more of ferric chloride, ferric nitrate, ferric sulfate, ferric acetate, and ferric acetylacetonate.

8. The method for preparing a calcined copper-iron alloy-type water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In step (2.1), the amount of deionized water is 30 mL to 100 mL.

9. The method for preparing a calcined copper-iron alloy-type water electrolysis hydrogen production catalyst according to claim 1, characterized in that: The calcination temperature in the tubular furnace is 200~900℃.

10. The method for preparing a calcined copper-iron alloy-type water electrolysis hydrogen production catalyst according to claim 1, characterized in that: The protective atmosphere includes one or more of nitrogen, argon and helium.

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