Aza-hybridized honeycomb carbon loaded FeOOH / FeNiCo-LDH heterostructure nanocomposite, a preparation method and application thereof

Abstract

The application provides a kind of nitrogen hetero honeycomb carbon loaded FeOOH / FeNiCo-LDH heterostructure nanocomposite, its preparation method and application, belong to nanocomposite field.The preparation method has such characteristics, including the following steps, organic salt and nitrogen-containing small molecule are completely dissolved in solvent, heated evaporation, high temperature calcination and acid etching, obtain nitrogen hetero honeycomb carbon, the obtained nitrogen hetero honeycomb carbon and metal cobalt precursor are mixed uniformly in solvent, add organic ligand to obtain metal organic framework / nitrogen hetero honeycomb carbon, the obtained metal organic framework / nitrogen hetero honeycomb carbon, metal nickel precursor and metal iron precursor are mixed uniformly in solvent to obtain mixed solution, then transfer to reaction kettle, reaction obtains the nanocomposite with excellent performance, good stability, typical honeycomb morphology and scale FeOOH / FeNiCo-LDH heterostructure.

Description

Technical Field

[0001] This invention belongs to the field of nanocomposite materials, specifically relating to a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material, its preparation method, and its applications. Background Technology

[0002] Faced with the dual challenges of energy shortages and environmental pollution, developing green, sustainable, low-cost, and efficient new energy systems is of paramount importance. Hydrogen, as a clean energy carrier with high energy density, is considered to play a crucial role in the construction of these new energy systems. Among these technologies, water electrolysis for hydrogen production, especially anion exchange membrane electrolyzers, has attracted significant attention due to its environmental friendliness, sustainability, safety, and stability. The water electrolysis reaction consists of two half-reactions: hydrogen evolution and oxygen evolution. The oxygen evolution reaction, as a key half-reaction, involves a complex multi-step proton-electron coupling process with slow kinetics and high overpotential, significantly impacting the efficiency of electrocatalytic water splitting. Although noble metal-based catalysts, such as RuO2 and IrO2, exhibit high catalytic activity, their high cost, scarcity, and poor stability limit their further development and application in water electrolysis energy devices.

[0003] Transition metal layered bimetallic hydroxides (TM-LDHs) and porous carbon materials are widely used as electrocatalysts for oxygen evolution reaction (OER) due to their wide availability, low cost, and ease of preparation. However, TM-LDHs suffer from poor conductivity, easy aggregation and stacking, and masking of active sites, which severely limit their intrinsic electrocatalytic activity. Effectively combining TM-LDHs and porous carbon can significantly improve the physicochemical properties such as the active site microenvironment and catalyst surface energy, thereby achieving a significant enhancement in electrocatalytic activity and stability. However, conventional hard or soft template methods for preparing porous carbon often require the introduction of additional template agents, such as silicon spheres, polystyrene spheres, and mesoporous silica, followed by a series of cumbersome steps including reverse casting, polymerization, high-temperature pyrolysis, and acid-base etching, which are not conducive to industrial-scale production.

[0004] Therefore, designing a low-cost, high-performance, high-durability, and simple-to-prepare electrocatalyst for oxygen evolution reaction has become an urgent problem to be solved. Summary of the Invention

[0005] This invention is made to solve the above-mentioned problems, and aims to provide a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material, its preparation method, and its application.

[0006] This invention provides a method for preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material, characterized by the following steps: Step S1, organic salt and nitrogen-containing small molecules are completely dissolved in a solvent, and then subjected to heating evaporation, high-temperature calcination and acid etching processes to obtain nitrogen-hybridized honeycomb carbon; Step S2, nitrogen-hybridized honeycomb carbon and a cobalt precursor are mixed uniformly in a solvent, and then an organic ligand is added to react, resulting in a metal-organic framework / nitrogen-hybridized honeycomb carbon; Step S3, the metal-organic framework / nitrogen-hybridized honeycomb carbon, a nickel precursor and an iron precursor are mixed uniformly in a solvent to obtain a mixed solution, and the mixed solution is transferred to a reaction vessel and reacted under a preset temperature control program to obtain a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0007] The method for preparing the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material provided by the present invention may also have the following characteristics: in step S1, the organic salt is any one or more of sodium gluconate, sodium acetate, ammonium citrate, potassium citrate, and sodium citrate; the nitrogen-containing small molecule is any one or more of aniline, alanine, glycine, urea, melamine, and hexamethylenetetramine; the solvent is any one or more of deionized water, methanol, ethanol, diethyl ether, N,N-dimethylacetamide, and N,N-dimethylformamide; and the molar ratio of the organic salt to the nitrogen-containing small molecule is 0.1 to 5.0.

[0008] The method for preparing the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material provided by the present invention may also have the following characteristics: In step S1, during the heating and evaporation process, the heating method is an oil bath, water bath, or sand bath, and the heating temperature is 50℃~200℃. During the high-temperature calcination process, the solid obtained from the heating and evaporation process is directly placed into a tube furnace for calcination without the need for additional template agent. The gas atmosphere is air, hydrogen, nitrogen, or argon, the temperature is 400℃~1200℃, the heating rate is 2℃ / min~20℃ / min, and the calcination time is 0.5h~8h. During the acid etching process, the acid solution used for etching is hydrochloric acid, sulfuric acid, or nitric acid, the acid concentration is 0.1M~2M, the etching temperature is 20℃~100℃, and the etching time is 10min~120min.

[0009] The method for preparing nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite materials provided by the present invention may also have the following characteristics: in step S2, the reaction temperature is 20℃~100℃, the reaction time is 1h~12h, the cobalt precursor is any one or more of cobalt oxalate, cobalt sulfate heptahydrate, cobalt nitrate hexahydrate, cobalt chloride hexahydrate, cobalt acetate tetrahydrate, and cobalt acetylacetonate, the organic ligand is any one or more of 2-aminoterephthalic acid, imidazole, 2-methylimidazolium, and 2-ethylimidazolium terephthalic acid, and the solvent is any one or more of deionized water, methanol, ethanol, diethyl ether, N,N-dimethylacetamide, and N,N-dimethylformamide.

[0010] The method for preparing the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material provided by the present invention may also have the following characteristics: in step S2, the amount of nitrogen-hybridized honeycomb carbon is 10 mg to 200 mg, the amount of metal precursor is 1-5 mmol, the amount of organic ligand is 0.5-50 mmol, the molar ratio of metal precursor to organic ligand is 0.1 to 2.0, and the amount of solvent is 10 mL to 200 mL.

[0011] The method for preparing nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite materials provided by the present invention may also have the following characteristics: in step S3, the preset temperature control program conditions are set as follows: reaction temperature 20℃~300℃, heating rate 1℃ / min~15℃ / min, reaction time 2h~20h, the nickel precursor is any one or more of nickel chloride hexahydrate, nickel acetate tetrahydrate, nickel sulfate hexahydrate, nickel nitrate hexahydrate, nickel oxalate, and nickel acetylacetonate, the iron precursor is any one or more of ferrous chloride tetrahydrate, ferrous sulfate heptahydrate, ferric nitrate nonahydrate, ferric acetate, anhydrous ferric chloride, ferric citrate, ferric acetate, and ferric acetylacetonate, and the solvent is any one or more of deionized water, methanol, ethanol ether, N,N-dimethylacetamide, and N,N-dimethylformamide.

[0012] The method for preparing the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material provided by the present invention may also have the following characteristics: in step S3, the amount of metal-organic framework / nitrogen-hybridized honeycomb carbon is 10 mg to 200 mg, the amount of solvent is 10 mL to 200 mL, the amount of nickel precursor is 0.5 to 3.0 mmol, and the amount of iron precursor is 0.01 to 0.2 mmol.

[0013] This invention provides a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material, characterized in that it is prepared by the method provided by this invention.

[0014] This invention provides the application of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material described in any of the above-described embodiments as an electrocatalyst.

[0015] The role and effect of invention

[0016] According to the present invention, a nitrogen-hybridized honeycomb carbon negative FeOOH / FeNiCo-LDH heterostructure nanocomposite material, its preparation method, and its application are disclosed. In the preparation process of the nitrogen-hybridized honeycomb carbon negative FeOOH / FeNiCo-LDH heterostructure nanocomposite material provided by the present invention, the first step involves completely dissolving organic salts and nitrogen-containing small molecules in a solvent, followed by heating and evaporation. Then, without the addition of an additional template agent, the solid obtained from the heating and evaporation process is directly placed into a tube furnace for high-temperature calcination. Finally, a simple acid etching process is performed to quickly and conveniently obtain nitrogen-hybridized honeycomb carbon. The second step involves combining the nitrogen-hybridized honeycomb carbon with gold... The cobalt precursor is uniformly mixed in a solvent, and then an organic ligand is added to react, resulting in a metal-organic framework / nitrogen-hybridized honeycomb carbon. In this step, the target metal-organic framework / nitrogen-hybridized honeycomb carbon can be obtained by effectively controlling the reaction conditions of the cobalt precursor and the organic ligand. In the third step, the metal-organic framework / nitrogen-hybridized honeycomb carbon, the nickel precursor, and the iron precursor are uniformly mixed in a solvent to obtain a mixed solution. By precisely controlling the reaction conditions of the nickel precursor, the iron precursor, and the metal-organic framework / nitrogen-hybridized honeycomb carbon, a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material is prepared.

[0017] Furthermore, the template-free high-temperature carbonization strategy employed in the preparation method of nitrogen-hybridized honeycomb carbon negative FeOOH / FeNiCo-LDH heterostructure nanocomposite material provided by this invention is more convenient and faster than the traditional hard template method or soft template method. The process is simple and the product processing is also relatively convenient and fast. It is suitable for preparing non-noble metal heterostructure catalysts with both high activity and high stability, such as Fe, Ni, and Cu.

[0018] Furthermore, this invention uses non-precious metal precursors and small organic molecules as synthetic raw materials, which are abundant in reserves and have low industrial costs, making them suitable for medium-scale industrial production.

[0019] Furthermore, the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material prepared in this invention has a typical honeycomb morphology and a scaly FeOOH / FeNiCo-LDH heterostructure, which can be used as a high-performance catalytic material with excellent performance and good stability. It has broad development prospects and application space in the catalytic conversion of energy and environment. Attached Figure Description

[0020] Figure 1 This is a scanning electron microscope image of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention;

[0021] Figure 2 This is a transmission electron microscope (TEM) image of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention.

[0022] Figure 3 This is a selected area electron diffraction pattern of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention;

[0023] Figure 4 This is an X-ray diffraction pattern of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention;

[0024] Figure 5 This is a graph showing the performance test data of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention. Detailed Implementation

[0025] To facilitate understanding of the technical means, creative features, objectives, and effects of this invention, the following embodiments, in conjunction with the accompanying drawings, illustrate a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material, its preparation method, and its applications.

[0026] To elaborate further.

[0027] <Example 1>

[0028] The preparation method of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in this embodiment includes the following steps:

[0029] Step 1: Dissolve any one or more of sodium gluconate, sodium acetate, ammonium citrate, potassium citrate, and sodium citrate, and any one or more of aniline, alanine, glycine, urea, melamine, and hexamethylenetetramine in deionized water, methanol, ethanol, diethyl ether, N,N-dimethylacetamide, and N,N-dimethylformamide. Then, heat and evaporate the solution in an oil bath, water bath, or sand bath at 50℃~200℃. Next, in an atmosphere of air, hydrogen, nitrogen, or argon, raise the temperature to 400℃~1200℃ at a rate of 2℃ / min~20℃ / min, and perform a high-temperature calcination process for 0.5h~8h. Finally, perform an acid etching process for 10min~120min in a hydrochloric acid, sulfuric acid, or nitric acid solution with an etching temperature of 20℃~100℃ and an acid concentration of 0.1M~2M to obtain nitrogen-hybridized honeycomb carbon. In this embodiment, the specific experimental process is as follows:

[0030] 7.90 g of sodium citrate and 0.91 g of urea were completely dissolved in 30 mL of deionized water. The solvent was evaporated in an oil bath at 110 °C. The resulting white powder was placed in a tube furnace and calcined at 800 °C for 1 h in an argon atmosphere. Then, it was etched with 0.1 M dilute hydrochloric acid, filtered, washed with water, and dried to obtain nitrogen-hybridized honeycomb carbon.

[0031] Step 2: 10 mg–200 mg of nitrogen-hybridized honeycomb carbon and 1–5 mmol of any one or more of cobalt oxalate, cobalt sulfate heptahydrate, cobalt nitrate hexahydrate, cobalt chloride hexahydrate, cobalt acetate tetrahydrate, and cobalt acetylacetonate are mixed thoroughly in 10 mL–200 mL of deionized water, methanol, ethanol, diethyl ether, N,N-dimethylacetamide, and N,N-dimethylformamide. Then, 0.5–50 mmol of any one or more of 2-aminoterephthalic acid, imidazole, 2-methylimidazolium, and 2-ethylimidazolium terephthalic acid are added to react with the mixture. After the reaction, a metal-organic framework / nitrogen-hybridized honeycomb carbon is obtained. The molar ratio of metal precursor to organic ligand is 0.1–2.0. In this example, the experimental procedure is as follows:

[0032] 294.0 mg of cobalt nitrate hexahydrate and 50 mg of nitrogen-hybridized honeycomb carbon obtained in step one were dispersed evenly in 20 mL of methanol solvent. Then, 20 mL of methanol solution containing 335.1 mg of 2-methylimidazole was added. The mixture was stirred and reacted at room temperature for 6 h. After centrifugation, methanol washing, and drying, metal-organic framework / nitrogen-hybridized honeycomb carbon was obtained.

[0033] Step 3: 10 mg–200 mg of metal-organic framework / nitrogen-hybridized honeycomb carbon and 0.5–3.0 mmol of any one or more of nickel chloride hexahydrate, nickel acetate tetrahydrate, nickel sulfate hexahydrate, nickel nitrate hexahydrate, nickel oxalate, and nickel acetylacetonate, and 0.01–0.2 mmol of any one or more of ferrous chloride tetrahydrate, ferrous sulfate heptahydrate, ferric nitrate nonahydrate, ferric acetate, anhydrous ferric chloride, ferric citrate, ferric acetate, and ferric acetylacetonate are mixed thoroughly in 10 mL–200 mL of deionized water, methanol, ethanol ether, N,N-dimethylacetamide, and N,N-dimethylformamide to obtain a mixed solution. The mixed solution is transferred to a reaction vessel, and the reaction temperature is set to 20 °C–300 °C, the heating rate is set to 1 °C / min–15 °C / min, and the reaction time is set to 2 h–20 h to carry out the reaction, thereby obtaining a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material. In this embodiment, the specific experimental process is as follows:

[0034] The 50 mg metal-organic framework / nitrogen-hybridized honeycomb carbon, 445.1 mg nickel nitrate hexahydrate, and 10.0 mg ferrous chloride tetrahydrate obtained in step 2 were dispersed evenly in 50 mL of ethanol solvent. The mixed solution was transferred to a solvothermal reactor, and the heating rate was set to 5 °C / min, the reaction temperature was set to 120 °C, and the reaction time was set to 8 h. After centrifugation, washing with ethanol, and drying, the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material was obtained.

[0035] Figure 1 This is a scanning electron microscope (SEM) image of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention. Figure 1 In the image, (a) is a scanning electron microscope image at 20K magnification, and (b) is a scanning electron microscope image at 100K magnification.

[0036] like Figure 1 As shown, the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite prepared in this embodiment has a typical honeycomb morphology and a scaly FeOOH / FeNiCo-LDH heterostructure.

[0037] Figure 2 This is a transmission electron microscope (TEM) image of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention. Figure 2 (a) is a low-magnification transmission electron microscope (TEM) image, and (b) is a high-resolution TEM image.

[0038] like Figure 2As shown, the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material prepared in this embodiment has obvious heterostructure interfaces and is uniformly distributed on the nitrogen-hybridized honeycomb carbon in the form of scales.

[0039] Figure 3 This is a selected area electron diffraction pattern of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention.

[0040] like Figure 3 As shown, the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material prepared in this embodiment has diffraction crystal forms of two phases, FeOOH and FeNiCo-LDH.

[0041] Figure 4 This is an X-ray diffraction pattern of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention.

[0042] like Figure 4 As shown, the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material prepared in this embodiment has three phase structures: graphite carbon, FeOOH, and FeNiCo-LDH.

[0043] Figure 5 This is a graph showing the performance test data of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material in Example 1 of the present invention. Figure 5 (a) shows the performance test data for the oxygen evolution reaction in freshwater, (b) shows the performance test data for the oxygen evolution reaction in seawater, (c) shows the performance test data when applied to anion exchange membrane electrolyzer for the electrolysis of freshwater, and (d) shows the performance test data when applied to anion exchange membrane electrolyzer for the electrolysis of seawater.

[0044] like Figure 5 As shown, the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material prepared in this embodiment has excellent oxygen evolution reaction performance in both freshwater and seawater. Furthermore, when used as an anode electrocatalyst in an anion exchange membrane electrolyzer for water electrolysis, it also achieves excellent water electrolysis performance.

[0045] Depend on Figure 1-5As shown, the method for preparing nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposites provided by this invention can successfully prepare nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposites with typical honeycomb morphology and flake-like FeOOH / FeNiCo-LDH heterostructure. This composite material has excellent catalytic activity and stability, and can be used as an efficient electrocatalyst for freshwater oxygen evolution reaction, seawater oxygen evolution reaction, and anion exchange membrane electrolyzer water electrolysis reaction.

[0046] <Example 2>

[0047] In this embodiment, based on the preparation conditions of Example 1, sodium citrate in step one of Example 1 was replaced with potassium citrate, and the other steps were the same as in Example 1, thus preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0048] <Example 3>

[0049] In this embodiment, based on the preparation conditions of Example 1, urea in step one of Example 1 was replaced with melamine, and the other steps were the same as in Example 1, to prepare a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0050] <Example 4>

[0051] In this embodiment, based on the preparation conditions of Example 1, the 0.91g urea in step one of Example 1 was replaced with 0.61g urea, and the other steps were the same as in Example 1, thus preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0052] <Example 5>

[0053] In this embodiment, based on the preparation conditions of Example 1, argon gas in step one of Example 1 was replaced with nitrogen gas, and the other steps were the same as in Example 1, thus preparing nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0054] <Example 6>

[0055] In this embodiment, based on the preparation conditions of Example 1, the dilute hydrochloric acid in step one of Example 1 was replaced with dilute sulfuric acid, and the other steps were the same as in Example 1, thus preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0056] <Example 7>

[0057] In this embodiment, based on the preparation conditions of Example 1, cobalt nitrate hexahydrate in step two of Example 1 was replaced with cobalt acetate tetrahydrate, and the other steps were the same as in Example 1, thus preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0058] <Example 8>

[0059] In this embodiment, based on the preparation conditions of Example 1, the 294.0 mg of cobalt nitrate hexahydrate in step two of Example 1 was replaced with 588.0 mg of cobalt nitrate hexahydrate. All other steps were the same as in Example 1, and nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material was prepared.

[0060] <Example 9>

[0061] In this embodiment, based on the preparation conditions of Example 1, the 50 mg of nitrogen-hybridized honeycomb carbon in step two of Example 1 was replaced with 100 mg of nitrogen-hybridized honeycomb carbon, and the other steps were the same as in Example 1, thus preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0062] <Example 10>

[0063] In this embodiment, based on the preparation conditions of Example 1, the stirring reaction time of 6h in step two of Example 1 was replaced with 12h, and the other steps were the same as in Example 1, thus preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0064] <Example 11>

[0065] In this embodiment, based on the preparation conditions of Example 1, the 50 mg metal-organic framework / nitrogen hybrid honeycomb carbon in step three of Example 1 was replaced with 100 mg metal-organic framework / nitrogen hybrid honeycomb carbon, and the other steps were the same as in Example 1, thus preparing a nitrogen hybrid honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0066] <Example 12>

[0067] In this embodiment, based on the preparation conditions of Example 1, 10.0 mg of ferrous chloride tetrahydrate in step three of Example 1 was replaced with 15.0 mg of ferrous chloride tetrahydrate, and the other steps were the same as in Example 1, thus preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0068] <Example 13>

[0069] In this embodiment, based on the preparation conditions of Example 1, the 50 mL ethanol in step three of Example 1 was replaced with 80 mL ethanol, and the other steps were the same as in Example 1, thus preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0070] <Example 14>

[0071] In this embodiment, based on the preparation conditions of Example 1, the reaction temperature of 120℃ in step three of Example 1 was replaced with 150℃, and the other steps were the same as in Example 1, so as to prepare nitrogen-hybridized honeycomb carbon supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0072] <Example 15>

[0073] In this embodiment, based on the preparation conditions of Example 1, the reaction time in step three of Example 1, which was 8h, was replaced with 10h. All other steps were the same as in Example 1, and a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material was prepared.

[0074] <Example 16>

[0075] In this embodiment, based on the preparation conditions of Example 1, the heating rate of 5℃ / min in step three of Example 1 was replaced with 8℃ / min, and the other steps were the same as in Example 1, so as to prepare nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material.

[0076] Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to this invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material, characterized in that, Includes the following steps: Step S1: Organic salts and nitrogen-containing small molecules are completely dissolved in a solvent, and nitrogen-hybridized honeycomb carbon is obtained through heating evaporation, high-temperature calcination and acid etching. Step S2: The nitrogen-hybridized honeycomb carbon and the cobalt precursor are mixed evenly in a solvent, and then an organic ligand is added to react. After the reaction, a metal-organic framework / nitrogen-hybridized honeycomb carbon is obtained. The organic ligand is 2-methylimidazole. The amount of nitrogen-hybridized honeycomb carbon is 10 mg to 200 mg, the amount of cobalt precursor is 1-5 mmol, the amount of organic ligand is 0.5-50 mmol, the molar ratio of cobalt precursor to organic ligand is 0.1 to 2.0, and the amount of solvent is 10 mL to 200 mL. Step S3: The metal-organic framework / nitrogen-hybridized honeycomb carbon, nickel precursor, and iron precursor are mixed uniformly in a solvent to obtain a mixed solution. The mixed solution is transferred to a reaction vessel and reacted under a preset temperature control program to obtain a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material. The amount of metal-organic framework / nitrogen-hybridized honeycomb carbon is 10 mg to 200 mg, the amount of solvent is 10 mL to 200 mL, the amount of nickel precursor is 0.5 to 3.0 mmol, and the amount of iron precursor is 0.01 to 0.2 mmol. The preset temperature control program is set as follows: reaction temperature 120℃ to 300℃, heating rate 1℃ / min to 15℃ / min, and reaction time 8 h to 20 h.

2. The method for preparing the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material according to claim 1, characterized in that: in, In step S1, the organic salt is any one or more of sodium gluconate, sodium acetate, ammonium citrate, potassium citrate, and sodium citrate. The nitrogen-containing small molecule is any one or more of aniline, alanine, glycine, urea, melamine, and hexamethylenetetramine. The solvent is any one or more selected from deionized water, methanol, ethanol, diethyl ether, N,N-dimethylacetamide, and N,N-dimethylformamide. The molar ratio of the organic salt to the nitrogen-containing small molecule is 0.1 to 5.

0.

3. The method for preparing the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material according to claim 1, characterized in that: in, In step S1, during the heating and evaporation process, the heating method is an oil bath, water bath, or sand bath, and the heating temperature is 50℃~200℃. During the high-temperature calcination process, the solid obtained from the heating and evaporation process is directly placed into a tube furnace for calcination without the addition of a template agent. The gas atmosphere is air, hydrogen, nitrogen, or argon. The temperature is 400℃~1200℃, the heating rate is 2℃ / min~20℃ / min, and the calcination time is 0.5h~8h. When performing the acid etching process, the acid solution used for etching is hydrochloric acid, sulfuric acid or nitric acid, the acid concentration is 0.1M~2M, the etching temperature is 20℃~100℃, and the etching time is 10min~120min.

4. The method for preparing the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material according to claim 1, characterized in that: in, In step S2, the reaction temperature is 20℃~100℃, and the reaction time is 1h~12h. The cobalt precursor is any one or more of cobalt oxalate, cobalt sulfate heptahydrate, cobalt nitrate hexahydrate, cobalt chloride hexahydrate, cobalt acetate tetrahydrate, and cobalt acetylacetonate. The solvent is any one or more of deionized water, methanol, ethanol, diethyl ether, N,N-dimethylacetamide, and N,N-dimethylformamide.

5. The method for preparing the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material according to claim 1, characterized in that: in, In step S3, the metallic nickel precursor is any one or more of nickel chloride hexahydrate, nickel acetate tetrahydrate, nickel sulfate hexahydrate, nickel nitrate hexahydrate, nickel oxalate, and nickel acetylacetonate. The metallic iron precursor is any one or more of ferrous chloride tetrahydrate, ferrous sulfate heptahydrate, ferric nitrate nonahydrate, ferric acetate, anhydrous ferric chloride, ferric citrate, ferric acetate, and ferric acetylacetone. The solvent is any one or more of deionized water, methanol, ethanol, diethyl ether, N,N-dimethylacetamide, and N,N-dimethylformamide.

6. A nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material, characterized in that: The composite material was prepared by the method described in any one of claims 1 to 5, which is a nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite.

7. The application of the nitrogen-hybridized honeycomb carbon-supported FeOOH / FeNiCo-LDH heterostructure nanocomposite material as described in claim 6 as an electrocatalyst.

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