Preparation method of electrolytic water hydrogen production catalyst based on rare earth composite CoP / NF

Abstract

The application discloses a preparation method of an electrolytic water hydrogen production catalyst based on a rare earth composite CoP / NF. The preparation method comprises the following steps: growing Co / NF on foam nickel, converting the Co / NF into CoP / NF, and then adopting an electrodeposition method to obtain the rare earth composite CoP / NF. The electrolytic water hydrogen production catalyst based on the rare earth composite CoP / NF prepared by the method can efficiently electrocatalyze water decomposition to produce hydrogen, and the preparation method is simple, low in cost and suitable for large-area popularization and application.

Description

Technical Field

[0001] This invention relates to the field of green hydrogen production technology, and in particular to a method for preparing a rare earth composite CoP / NF-based catalyst for hydrogen production by water electrolysis. Background Technology

[0002] The growing global energy demand and the increasingly severe environmental problems caused by fossil fuel consumption have made the development of clean and sustainable alternative energy sources a core challenge. Hydrogen energy, due to its high energy density and lack of pollution, is considered a highly promising next-generation energy carrier. Electrocatalytic water splitting is an important pathway for green hydrogen production. However, its cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER) involve high thermodynamic barriers and slow kinetic processes, requiring highly efficient, stable, and low-cost bifunctional electrocatalysts, which is crucial for its commercialization.

[0003] Currently, the best-performing electrocatalysts are made of noble metals, but their high cost and scarcity limit their widespread application. Transition metal phosphides (TMPs) have attracted much attention as non-noble metal electrocatalysts. Among them, nickel-based and cobalt-based phosphides (such as CoP) have shown excellent catalytic activity in HER and OER, making them ideal alternatives to noble metal catalysts. However, single transition metal phosphides have bottlenecks such as insufficient intrinsic activity of active sites, difficulty in electronic structure regulation, and poor long-term stability.

[0004] Rare earth elements, with their unique 4f electronic structure, variable valence states, and "lanthanide contraction" effect, can act as "electron modulators" to optimize the electronic structure of transition metal sites, induce lattice distortion, increase defect sites, and enhance catalytic activity. Furthermore, rare earth elements readily form stable chelate structures with phosphorus, providing theoretical support for catalyst design. Existing research has confirmed that rare earth composites can significantly improve the catalytic performance of phosphides; however, this field is still in its early stages, and further systematic and in-depth research on rare earth composite CoP-based catalysts is needed.

[0005] Therefore, designing and preparing rare earth composite CoP / NF water electrolysis hydrogen production catalysts, exploring the regulation mechanism of rare earth composites, and optimizing catalytic performance are of great research significance and application value for breaking through the bottleneck of non-precious metal catalysts and promoting the commercialization of electrocatalytic water electrolysis technology.

[0006] This invention addresses the shortcomings of existing technologies by preparing a rare-earth composite CoP / NF-based catalyst for hydrogen production through water electrolysis and applying it to a water splitting system. This catalyst can efficiently produce green hydrogen, providing a new path for the development of green energy and helping to alleviate the energy crisis.

[0007] Based on the above technical background, this invention develops a method for preparing a rare earth composite CoP / NF catalyst for hydrogen production through water electrolysis, which has not been reported before. Summary of the Invention

[0008] The purpose of this invention is to solve the technical problems existing in the prior art and to provide a method for preparing a rare earth composite CoP / NF-based catalyst for hydrogen production by water electrolysis.

[0009] To achieve the above objectives, the technical solution provided by this invention is: a method for preparing a rare-earth composite CoP / NF catalyst for hydrogen production through water electrolysis, characterized in that: the preparation method first grows Co / NF on nickel foam, then converts it to CoP / NF, and then obtains the rare-earth composite CoP / NF by electrodeposition. Specifically, it includes the following steps:

[0010] Step (1): Preparation of Co / NF

[0011] Cut the nickel foam (NF) into small pieces (2×3 cm). 2 The material was pretreated with acetone, dilute hydrochloric acid, deionized water, and anhydrous ethanol using ultrasonication, and then freeze-dried. Subsequently, 0.054 g Co(NO3)2·6H2O, 0.243 g urea, and 0.060 g NH4F were added to 18 mL of deionized water and stirred on a magnetic stirrer for 30 min to form a homogeneous solution. During stirring, 160 μL of hydrogen peroxide solution was added dropwise. A piece of pretreated nickel foam (NF) was immersed in the above solution, and the solution was transferred to a reaction vessel and subjected to hydrothermal reaction at a specific temperature for a certain time. After the reaction was completed, the product was collected after rinsing several times with deionized water and anhydrous ethanol, and then freeze-dried.

[0012] Step (2): Preparation of CoP / NF

[0013] One piece of Co / NF sheet prepared in step (1) and 1 g of anhydrous sodium hypophosphite were placed in two separate ceramic boats. The two boats were then transferred to a tube furnace, with the boat containing the anhydrous sodium hypophosphite upstream of the aeration stream and the boat containing the Co / NF sheet downstream of the aeration stream, and heated in a N2 atmosphere at 3 °C for 3 min. -1 The product CoP / NF is obtained by heating to a certain temperature at a certain heating rate, holding it at that temperature for a certain time, and then cooling it.

[0014] Step (3): Preparation of rare earth composite CoP / NF

[0015] Deposition is typically carried out in a typical three-electrode setup, with CoP / NF as the working electrode, a stone rod as the counter electrode, and Ag / AgCl as the reference electrode, in a configuration consisting of 36 × 10⁻⁶ electrodes. −3 mol Ni(NO3)2·6 H2O, 4 × 10 -3In an electrolyte consisting of 0.15 mol rare earth salt solution and 0.15 mol urea solution, a constant potential deposition was carried out at -0.85 V relative to Ag / AgCl, and the reaction was carried out at 85 °C for 800 s. After the reaction was completed, the product was washed several times with deionized water and anhydrous ethanol, and then collected and freeze-dried in a freeze dryer to obtain the rare earth composite CoP / NF product.

[0016] Preferably, the hydrothermal reaction temperature range in step (1) is 100-160 ℃.

[0017] Preferably, the hydrothermal reaction time in step (1) is 10-20 hours.

[0018] Preferably, in step (2), the temperature is 3℃ min. -1 The heating rate allows for a temperature range of 300-500 ℃.

[0019] Preferably, in step (2), the temperature is 3℃ min. -1 After heating to the specified temperature at the specified heating rate, the holding time ranges from 1 to 4 hours.

[0020] Preferably, the 4 × 10 added in step (3) -3 The rare earth salt solutions are Y(NO3)3·6 H2O, Ce(NO3)3·6 H2O, Yb(NO3)3·6 H2O, and La(NO3)3·6 H2O.

[0021] Beneficial effects of this invention:

[0022] 1. The rare earth composite CoP / NF-based water electrolysis hydrogen production catalyst prepared in this invention can efficiently electrocatalyze water splitting to produce hydrogen.

[0023] 2. The rare earth composite CoP / NF-based water electrolysis hydrogen production catalyst prepared in this invention is simple to prepare, low in cost, and suitable for large-scale application. Attached Figure Description

[0024] The accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, are illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention.

[0025] Figure 1 Transmission electron microscopy image of the rare earth composite CoP / NF-based hydrogen production catalyst for water electrolysis prepared in Specific Example 1 of the present invention;

[0026] Figure 2 The image shows the electrocatalytic total water splitting hydrogen production LSV of the rare earth composite CoP / NF-based water electrolysis hydrogen production catalyst prepared in Specific Example 2 of this invention. Detailed Implementation

[0027] This section will describe in detail specific embodiments of the present invention. Preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but they should not be construed as limiting the scope of protection of the present invention. Specific Implementation Example 1

[0029] Step (1): Preparation of Co / NF

[0030] Cut the nickel foam (NF) into small pieces (2×3 cm). 2 The material was pretreated with acetone, dilute hydrochloric acid, deionized water, and anhydrous ethanol using ultrasonication, and then freeze-dried. Subsequently, 0.054 g Co(NO3)2·6H2O, 0.243 g urea, and 0.060 g NH4F were added to 18 mL of deionized water and stirred on a magnetic stirrer for 30 min to form a homogeneous solution. During stirring, 160 μL of hydrogen peroxide solution was added dropwise. A piece of pretreated nickel foam (NF) was immersed in the above solution, and the solution was transferred to a reaction vessel and subjected to hydrothermal reaction at 100 °C for 10 hours. After the reaction, the product was washed several times with deionized water and anhydrous ethanol, collected, and freeze-dried.

[0031] Step (2): Preparation of CoP / NF

[0032] One piece of Co / NF sheet prepared in step (1) and 1 g of anhydrous sodium hypophosphite were placed in two separate ceramic boats. The two boats were then transferred to a tube furnace, with the boat containing the anhydrous sodium hypophosphite upstream of the aeration stream and the boat containing the Co / NF sheet downstream of the aeration stream, and heated in a N2 atmosphere at 3 °C for 3 min. -1 The product CoP / NF was obtained by heating to 300℃ at a certain heating rate and holding for 1 hour, followed by cooling.

[0033] Step (3): Preparation of rare earth composite CoP / NF

[0034] Deposition is typically carried out in a typical three-electrode setup, with CoP / NF as the working electrode, a stone rod as the counter electrode, and Ag / AgCl as the reference electrode, in a 36 × 10⁻⁶ electrode. −3 mol Ni(NO3)2·6 H2O, 4 × 10 -3In an electrolyte consisting of 0.15 mol Y(NO3)3·6H2O and 0.15 mol urea solution, a constant potential deposition was carried out at -0.85 V relative to Ag / AgCl, and the reaction was carried out at 85 °C for 800 s. After the reaction, the product was washed several times with deionized water and anhydrous ethanol, and then collected and freeze-dried in a freeze dryer to obtain the rare earth composite CoP / NF product. Specific Implementation Example 2

[0036] Step (1): Preparation of Co / NF

[0037] Cut the nickel foam (NF) into small pieces (2×3 cm). 2 The material was pretreated with acetone, dilute hydrochloric acid, deionized water, and anhydrous ethanol using ultrasonication, and then freeze-dried. Subsequently, 0.054 g Co(NO3)2·6H2O, 0.243 g urea, and 0.060 g NH4F were added to 18 mL of deionized water and stirred on a magnetic stirrer for 30 min to form a homogeneous solution. During stirring, 160 μL of hydrogen peroxide solution was added dropwise. A piece of pretreated nickel foam (NF) was immersed in the above solution, and the solution was transferred to a reaction vessel and subjected to hydrothermal reaction at 120 °C for 16 hours. After the reaction was completed, the product was collected after rinsing several times with deionized water and anhydrous ethanol, and then freeze-dried.

[0038] Step (2): Preparation of CoP / NF

[0039] One piece of Co / NF sheet prepared in step (1) and 1 g of anhydrous sodium hypophosphite were placed in two separate ceramic boats. The two boats were then transferred to a tube furnace, with the boat containing the anhydrous sodium hypophosphite upstream of the aeration stream and the boat containing the Co / NF sheet downstream of the aeration stream, and heated in a N2 atmosphere at 3 °C for 3 min. -1 The product CoP / NF was obtained by heating to 350°C and holding for 2 hours at a certain heating rate and then cooling.

[0040] Step (3): Preparation of rare earth composite CoP / NF

[0041] Deposition is typically carried out in a typical three-electrode setup, with CoP / NF as the working electrode, a stone rod as the counter electrode, and Ag / AgCl as the reference electrode, in a 36 × 10⁻⁶ electrode. −3 mol Ni(NO3)2·6 H2O, 4 × 10 -3In an electrolyte consisting of 0.15 mol Ce(NO3)3·6H2O and 0.15 mol urea solution, a constant potential deposition was carried out at -0.85 V relative to Ag / AgCl, and the reaction was carried out at 85 °C for 800 s. After the reaction, the product was washed several times with deionized water and anhydrous ethanol, and then collected and freeze-dried in a freeze dryer to obtain the rare earth composite CoP / NF product. Specific Implementation Example 3

[0043] Step (1): Preparation of Co / NF

[0044] Cut the nickel foam (NF) into small pieces (2×3 cm). 2 The material was pretreated with acetone, dilute hydrochloric acid, deionized water, and anhydrous ethanol using ultrasonication, and then freeze-dried. Subsequently, 0.054 g Co(NO3)2·6H2O, 0.243 g urea, and 0.060 g NH4F were added to 18 mL of deionized water and stirred on a magnetic stirrer for 30 min to form a homogeneous solution. During stirring, 160 μL of hydrogen peroxide solution was added dropwise. A piece of pretreated nickel foam (NF) was immersed in the above solution, and the solution was transferred to a reaction vessel and subjected to hydrothermal reaction at 140 °C for 18 hours. After the reaction was completed, the product was collected after rinsing several times with deionized water and anhydrous ethanol, and then freeze-dried.

[0045] Step (2): Preparation of CoP / NF

[0046] One piece of Co / NF sheet prepared in step (1) and 1 g of anhydrous sodium hypophosphite were placed in two separate ceramic boats. The two boats were then transferred to a tube furnace, with the boat containing the anhydrous sodium hypophosphite upstream of the aeration stream and the boat containing the Co / NF sheet downstream of the aeration stream, and heated in a N2 atmosphere at 3 °C for 3 min. -1 The product CoP / NF was obtained by heating to 450℃ at a certain heating rate and holding for 3 hours, followed by cooling.

[0047] Step (3): Preparation of rare earth composite CoP / NF

[0048] Deposition is typically carried out in a typical three-electrode setup, with CoP / NF as the working electrode, a stone rod as the counter electrode, and Ag / AgCl as the reference electrode, in a 36 × 10⁻⁶ electrode. −3 mol Ni(NO3)2·6 H2O, 4 × 10 -3In an electrolyte consisting of 0.15 mol Yb(NO3)3·6H2O and 0.15 mol urea solution, a constant potential deposition was carried out at -0.85 V relative to Ag / AgCl, and the reaction was carried out at 85 °C for 800 s. After the reaction, the product was washed several times with deionized water and anhydrous ethanol, and then collected and freeze-dried in a freeze dryer to obtain the rare earth composite CoP / NF.

[0049] Specific Experiment Example 4

[0050] Step (1): Preparation of Co / NF

[0051] Cut the nickel foam (NF) into small pieces (2×3 cm). 2 The material was pretreated with acetone, dilute hydrochloric acid, deionized water, and anhydrous ethanol using ultrasonication, and then freeze-dried. Subsequently, 0.054 g Co(NO3)2·6H2O, 0.243 g urea, and 0.060 g NH4F were added to 18 mL of deionized water and stirred on a magnetic stirrer for 30 min to form a homogeneous solution. During stirring, 160 μL of hydrogen peroxide solution was added dropwise. A piece of pretreated nickel foam (NF) was immersed in the above solution, and the solution was transferred to a reaction vessel and subjected to hydrothermal reaction at 160 °C for 20 hours. After the reaction was completed, the product was collected after rinsing several times with deionized water and anhydrous ethanol, and then freeze-dried.

[0052] Step (2): Preparation of CoP / NF

[0053] One piece of Co / NF sheet prepared in step (1) and 1 g of anhydrous sodium hypophosphite were placed in two separate ceramic boats. The two boats were then transferred to a tube furnace, with the boat containing the anhydrous sodium hypophosphite upstream of the aeration stream and the boat containing the Co / NF sheet downstream of the aeration stream, and heated in a N2 atmosphere at 3 °C for 3 min. -1 The product CoP / NF was obtained by heating to 500℃ at a certain heating rate and holding for 4 hours, followed by cooling.

[0054] Step (3): Preparation of rare earth composite CoP / NF

[0055] Deposition is typically carried out in a typical three-electrode setup, with CoP / NF as the working electrode, a stone rod as the counter electrode, and Ag / AgCl as the reference electrode, in a 36 × 10⁻⁶ electrode. −3 mol Ni(NO3)2·6 H2O, 4 × 10 -3In an electrolyte consisting of 0.15 mol La(NO3)3·6H2O and 0.15 mol urea solution, a constant potential deposition was carried out at -0.85 V relative to Ag / AgCl, and the reaction was carried out at 85 °C for 800 s. After the reaction, the product was washed several times with deionized water and anhydrous ethanol, and then collected and freeze-dried in a freeze dryer to obtain the rare earth composite CoP / NF.

[0056] The rare earth composite CoP / NF-based water electrolysis hydrogen production catalyst prepared in this invention can efficiently electrocatalyze water splitting to produce hydrogen, and its preparation is simple, low-cost, and suitable for large-scale application.

[0057] Without causing conflict, those skilled in the art can freely combine and use the above-mentioned additional technical features.

[0058] The above description is only a preferred embodiment of the present invention. Any technical solution that achieves the purpose of the present invention by essentially the same means is within the protection scope of the present invention.

Claims

1. A method for preparing a rare earth composite CoP / NF-based catalyst for hydrogen production through water electrolysis. The method is characterized by the following steps: First, Co / NF is grown on nickel foam, then converted to CoP / NF, and finally, rare earth composite CoP / NF is obtained by electrodeposition. Step (1): Preparation of Co / NF Cut the nickel foam (NF) into small pieces (2×3 cm). 2 The material was pretreated with acetone, dilute hydrochloric acid, deionized water, and anhydrous ethanol using ultrasonication, and then freeze-dried. Subsequently, 0.054 g Co(NO3)2·6H2O, 0.243 g urea, and 0.060 g NH4F were added to 18 mL of deionized water and stirred on a magnetic stirrer for 30 min to form a homogeneous solution. During stirring, 160 μL of hydrogen peroxide solution was added dropwise. A piece of pretreated nickel foam (NF) was immersed in the above solution, and the solution was transferred to a reaction vessel and subjected to hydrothermal reaction at a specific temperature for a certain time. After the reaction was completed, the product was collected after rinsing several times with deionized water and anhydrous ethanol, and then freeze-dried. Step (2): Preparation of CoP / NF One piece of Co / NF sheet prepared in step (1) and 1 g of anhydrous sodium hypophosphite were placed in two separate ceramic boats. The two boats were then transferred to a tube furnace, with the boat containing the anhydrous sodium hypophosphite upstream of the aeration stream and the boat containing the Co / NF sheet downstream of the aeration stream, and heated in a N2 atmosphere at 3 °C for 3 min. -1 The product CoP / NF is obtained by heating to a certain temperature at a certain heating rate, holding it at that temperature for a certain time, and then cooling it. Step (3): Preparation of rare earth composite CoP / NF Deposition is typically carried out in a typical three-electrode setup, with CoP / NF as the working electrode, a stone rod as the counter electrode, and Ag / AgCl as the reference electrode, in a configuration consisting of 36 × 10⁻⁶ electrodes. −3 mol Ni(NO3)2·6 H2O, 4×10 -3 In an electrolyte consisting of 0.15 mol rare earth salt solution and 0.15 mol urea solution, a constant potential deposition was carried out at -0.85 V relative to Ag / AgCl, and the reaction was carried out at 85 °C for 800 s. After the reaction, the product was washed several times with deionized water and anhydrous ethanol, and then collected and freeze-dried in a freeze dryer to obtain the rare earth composite CoP / NF product.

2. The preparation method of a rare earth composite CoP / NF-based water electrolysis hydrogen production catalyst according to claim 1, characterized in that: The hydrothermal reaction temperature range in step (1) is 100-160 ℃.

3. The preparation method of a rare earth composite CoP / NF-based water electrolysis hydrogen production catalyst according to claim 1, characterized in that: The hydrothermal reaction time in step (1) is 10-20 hours.

4. The preparation method of a rare earth composite CoP / NF-based water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In step (2), the temperature is 3℃ min. -1 The heating rate allows for a temperature range of 300-500 ℃.

5. The preparation method of a rare earth composite CoP / NF-based water electrolysis hydrogen production catalyst according to claim 1, characterized in that: In step (2), the temperature is 3℃ min. -1 After heating to the specified temperature at the specified heating rate, the holding time ranges from 1 to 4 hours. Preferably, the 4 × 10 added in step (3) -3 The rare earth salt solutions are Y(NO3)3·6H2O, Ce(NO3)3·6H2O, Yb(NO3)3·6H2O, and La(NO3)3·6H2O.

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