A synthesis method for anchoring and growing ultrafine metal nanoparticles based on single-molecule dispersion coordination molecules

Abstract

This invention relates to a method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth. The method involves immobilizing metal coordination molecules or metal-free central coordination molecules on the surface of a carbon-based conductive carrier in a monomolecular dispersion manner, resulting in M-N nanoparticles. x Coordination structure or N x A molecular anchoring site complex with a coordination structure is prepared; the molecular anchoring site complex is mixed and reacted with a target metal precursor solution, so that the target metal precursor is selectively adsorbed and enriched at the coordination sites to obtain an intermediate product; the intermediate product is added to a mixed atmosphere of inert atmosphere and reducing atmosphere for reduction treatment to obtain the ultrafine metal nanoparticles grown based on monomolecular dispersed coordination molecular anchoring, which effectively inhibits agglomeration and improves metal utilization.

Description

Technical Field

[0001] This invention relates to the fields of nanocatalytic materials and interface chemistry, and in particular to a method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth. Background Technology

[0002] Transition metal nanoparticles, represented by noble metals, are widely used in electrocatalysis, fuel cells, water electrolysis, CO2 electroreduction, nitrate reduction, and organic synthesis due to their abundant surface active sites and excellent electron transport capabilities. The smaller the nanoparticle size and the higher its dispersion, the more effective exposed sites a unit mass of metal can provide, thus significantly improving metal utilization and mass activity. When the particle size enters the sub-2 nm or even cluster / atomic scale, the electronic structure and adsorption behavior of the material may also change, resulting in higher intrinsic activity and selectivity. Therefore, achieving the controllable synthesis and stable loading of ultrafine metal nanoparticles has become one of the core issues in the design of high-performance catalytic materials.

[0003] In existing technologies, ultrafine nanoparticles are typically prepared using routes such as impregnation reduction, chemical reduction, colloidal methods, in-situ growth, or high-temperature pyrolysis, and rely on carbon supports, metal oxides, or porous materials for dispersion and fixation. However, due to the high surface energy of metal particles, especially under low loading and high-temperature / electrochemical conditions, they are prone to migration, sintering, agglomeration, or detachment, leading to particle size increase, activity decay, and decreased stability. To improve anchoring ability, traditional methods often construct anchoring points through carrier defect engineering (such as introducing vacancies or edge sites), heteroatom doping (such as N, S, and P doping), or the introduction of coordinating groups (such as -NH2, -COOH, etc.); there are also reports on constructing MN x (M represents a transition metal) The structure enhances the interaction between the metal and the support, inhibiting the growth of noble metal particles. However, the above methods still have several limitations: First, the spatial distribution and chemical environment of defects and doping sites are often uneven, making it difficult to achieve precise control over the metal nucleation site and growth process; Second, pyrolysis or high-temperature treatment can easily cause site reconstruction, resulting in unclear anchoring site structures and insufficient repeatability; Third, although some methods can achieve strong anchoring, they can easily cause excessive fixation of metal sites or uncontrollable interface environment, thereby limiting the accessibility of active sites and the transport of reaction intermediates.

[0004] Therefore, there is an urgent need to develop a well-defined, tunable, and versatile anchoring and growth strategy to selectively capture, locally enrich, and control the nucleation of metal precursors under mild conditions, thereby constructing ultrafine metal nanoparticles with small particle size, narrow distribution, and strong anti-agglomeration ability, while also ensuring high activity and long-term stability. Metal coordination molecules such as phthalocyanines and metalloporphyrins possess stable M-N4 coordination structures, designable electronic effects, and good structural tunability, and are considered potential solutions for constructing well-defined anchoring sites. However, these planar large π-conjugated molecules are prone to π-π stacking or van der Waals interactions on carbon-based surfaces, leading to aggregation, which reduces their dispersibility and effective anchoring ability, making it difficult to achieve precise control over the nucleation and growth of nanoparticles.

[0005] Therefore, there is an urgent need to propose a new technical solution to meet the requirements of high-performance catalysis and device applications for material consistency, scalable preparation and stability. Summary of the Invention

[0006] This invention relates to a method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth. The method involves immobilizing metal coordination molecules or metal-free central coordination molecules on the surface of a carbon-based conductive carrier in a monomolecular dispersion manner, resulting in nanoparticles with MN... x Coordination structure or N x A molecular anchoring site complex with a coordination structure is prepared; the molecular anchoring site complex is mixed and reacted with a target metal precursor solution, so that the target metal precursor is selectively adsorbed and enriched at the coordination sites to obtain an intermediate product; the intermediate product is added to a mixed atmosphere of inert atmosphere and reducing atmosphere for reduction treatment to obtain the ultrafine metal nanoparticles grown based on monomolecular dispersed coordination molecular anchoring, which effectively inhibits agglomeration and improves metal utilization.

[0007] The purpose of this invention is to provide a method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth, wherein the method comprises: S1. Metal-coordinated molecules or metal-free central coordination molecules are immobilized on the surface of a carbon-based conductive carrier in a monomolecular dispersion manner to obtain molecules with MN. x Coordination structure or N x Molecular anchoring site complexes with coordination structures; S2. Mix the molecular anchoring site complex described in S1 with the target metal precursor solution to react, so that the target metal precursor is selectively adsorbed and enriched at the coordination site to obtain the intermediate product. S3. The intermediate product is added to a mixture of inert and reducing atmospheres for reduction treatment to obtain the ultrafine metal nanoparticles grown based on monomolecular dispersed coordination molecules. in, M is selected from one or more of Co, Fe, Ni, Cu, Mn, Cr, and Zn.

[0008] Furthermore, the metal coordination molecule is selected from one or more of metal phthalocyanines, metal porphyrins, or their derivatives; The metal-free central coordinating molecule is selected from one or more of the following: metal-free central phthalocyanine (H2Pc) and metal-free central porphyrin (H2Por).

[0009] Furthermore, the metal coordination molecule is preferably a macrocyclic conjugated complex of a metal phthalocyanine or metal porphyrin with a defined M-N4 structure.

[0010] Furthermore, the single-molecule dispersion method is as follows: a carbon-based conductive carrier is dispersed in a solvent to obtain a carbon-based conductive carrier dispersion, and a metal coordination molecule or a metal-free central coordination molecule is dispersed in a solvent to obtain a coordination molecule dispersion. The carbon-based conductive carrier dispersion and the coordination molecule dispersion are mixed and subjected to ultrasonic dispersion treatment.

[0011] Furthermore, the ultrasonic dispersion time is 1-4 h.

[0012] Furthermore, the carbon-based conductive carrier is selected from one or more of carbon nanotubes, graphene, carbon black, mesoporous carbon, carbon fiber cloth, and carbon paper.

[0013] Furthermore, the mixing reaction involves dispersing the molecular anchoring site complex in a solvent, adding a target metal precursor solution, and ultrasonically treating it to obtain an intermediate product.

[0014] Furthermore, the mixing reaction takes place over a period of 1-3 hours.

[0015] Furthermore, the target metal precursor is selected from one or more salts or complexes of Pt, Pd, Au, Ru, Ir, and Ag.

[0016] Furthermore, the reduction treatment is carried out at a temperature of 200-400℃ to suppress the migration and aggregation of ultrafine metal nanoparticles.

[0017] Furthermore, the reduction process takes 1-3 hours.

[0018] Furthermore, the metal coordination molecule contains peripheral substituents for regulating electronic effects and / or steric hindrance and inhibiting molecule aggregation on the carbon support, wherein the peripheral substituents are selected from one or more of halogens, -CF3, -SO3H, -COOH, -NH2, methoxy, and alkyl.

[0019] Furthermore, the metal coordination molecule contains an axial coordination group or introduces an axial ligand to enhance the capture of the target metal precursor or regulate the nucleation site density. The axial ligand is selected from one or more of pyridine, imidazole, amine, halogen ligand, and hydroxyl ligand.

[0020] Furthermore, S1 achieves the fixation of the metal coordination molecule or the metal-free central coordination molecule in a monomolecular dispersion manner through solvent regulation, self-assembly adsorption, surface functionalization or covalent bonding, and the surface functionalization includes the introduction of nitrogen-containing functional groups and / or oxygen-containing functional groups.

[0021] Furthermore, a second target metal precursor is introduced in S3 to obtain the bimetallic or alloy ultrafine metal nanoparticles grown based on monomolecular dispersed coordination molecule anchoring.

[0022] Furthermore, the second target metal precursor is selected from one or more of Co, Ni, Fe, Cu, Pd, and Au.

[0023] Another object of the present invention is to provide a product obtained by the above-described synthesis method based on monomolecular dispersed coordination molecule anchoring growth of ultrafine metal nanoparticles, the product comprising a carbon-based conductive support, a coordination molecule monomolecularly dispersed on the surface of the support, and ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth.

[0024] Furthermore, the average particle size of the ultrafine metal nanoparticles grown based on monomolecular dispersed coordination molecular anchoring is ≤2 nm, and they exhibit a highly dispersed distribution on the carrier surface.

[0025] Furthermore, the metal coordinating molecule in the product is cobalt phthalocyanine (CoPc) or iron phthalocyanine (FePc).

[0026] Furthermore, the ultrafine metal nanoparticles in the product are Pt ultrafine nanoparticles.

[0027] Furthermore, the product contains one or more of the following structures between the ultrafine metal nanoparticles and the metal coordination molecules: Pt-N coordination and Pt-M (where M is the central metal of the coordination molecule) proximity coupling structures.

[0028] Furthermore, the application of the product in electrocatalytic reactions includes one or more of the following: alkaline hydrogen evolution reaction, anion exchange membrane water electrolysis, oxygen reduction reaction, oxygen evolution reaction, hydrogen oxidation reaction, carbon dioxide reduction reaction, or nitrate reduction reaction.

[0029] The present invention has the following beneficial effects: (1) Using single-molecule dispersed coordination molecules as well-defined anchoring points, precise molecular-level control of metal nucleation sites and growth processes can be achieved, significantly improving particle size controllability and repeatability.

[0030] (2) Through the capture and local enrichment of M-N4 sites, ultrafine nanoparticles can be constructed with low metal loading, thereby improving metal utilization and mass activity potential.

[0031] (3) By introducing molecular engineering techniques such as substituents and axial coordination, anchoring strength, dispersion stability, interfacial wettability and electronic structure can be controlled simultaneously to achieve “structure controllability and performance orientation optimization”.

[0032] (4) The obtained ultrafine nanoparticles form a strong interfacial interaction with the carrier, which effectively inhibits migration, sintering and shedding under thermal / electrochemical conditions and enhances long-term stability.

[0033] (5) It can be extended to a variety of coordination molecules and a variety of metal systems, and is suitable for applications such as electrocatalysis and energy device electrodes, and has the potential for scaled-up preparation. Attached Figure Description

[0034] Figure 1 A schematic diagram of a synthesis method for the controllable growth of ultrafine metal nanoparticles based on monomolecular dispersed coordination molecules is shown.

[0035] Figure 2 The diagram shows a schematic of the synthesis method for controlling the growth of ultrafine Pt nanoparticles based on monomolecular dispersed coordination molecules, as illustrated in Examples 1-3.

[0036] Figure 3 A schematic diagram of the structure of Pt nanoparticles grown based on carbon nanotubes is shown in Comparative Example 1.

[0037] Figure 4 The surface morphology scanning electron microscope images of Examples 1-3 and Comparative Example 1 are shown; in, Figure 4 (ai) shows a scanning electron microscope image of the surface morphology of Example 1; Figure 4 (a-ii) in the figure shows scanning electron microscope images of the surface morphology of Example 2; Figure 4 (a-iii) in the figure show scanning electron microscope images of the surface morphology of Example 3; Figure 4 (b) shows a scanning electron microscope image of the surface morphology of Comparative Example 1.

[0038] Figure 5 The microstructure double aberration electron microscope images of Examples 1-3 and Comparative Example 1 are shown; in, Figure 5 Image (a) shows a double spherical aberration electron microscope image of the microstructure of Comparative Example 1; Figure 5 (b) shows a double aberration electron microscope image of the microstructure of Example 1; Figure 5 (c) shows a double aberration electron microscope image of the microstructure of Example 2; Figure 5 Image (d) shows a double spherical aberration electron microscope image of the microstructure of Example 3.

[0039] Figure 6 Performance test graphs of Examples 1-3, Comparative Example 1, and a commercial platinum-carbon catalyst (Pt / C) in alkaline electrolytes are shown.

[0040] Figure 7 The diagram shows the industrial-grade current performance test of the device assembled with the water electrolysis membrane in Example 1. Detailed Implementation

[0041] To more clearly illustrate the technical solution of the present invention, the following embodiments are provided. Unless otherwise stated, the raw materials, reactions, and post-processing methods appearing in the embodiments are all commercially available raw materials and technical methods well known to those skilled in the art.

[0042] The terms "preferred," "more preferably," and "more suitable" used in this invention refer to embodiments of the invention that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this invention.

[0043] It should be understood that, except in any operational instance or otherwise indicated, the amounts or all figures representing ingredients used, for example, in the specification and claims, should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise stated, the numerical parameters set forth in the following specification and appended claims are approximate values ​​varying according to the desired performance to be obtained according to the invention.

[0044] The embodiments and comparative examples of the present invention use the following raw materials: Commercial platinum-carbon catalyst (Pt / C): Platinum loading of 20 wt%, purchased from Macklin.

[0045] Multi-walled carbon nanotubes: diameter 10-30 nm, grade FT 9000, purchased from Canano Technology.

[0046] Example 1 A method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth, the method comprising: S1. Mix 150 mg of multi-walled carbon nanotubes with 60 mL of N,N-dimethylformamide (DMF) and sonicate for 80 min; mix 8 mg of CoPc with 15 mL of DMF and sonicate for 80 min; mix the two dispersions together and sonicate for 2.5 h, then centrifuge. Wash the centrifuged dispersions with DMF, ethanol, and water, respectively, and freeze-dry to obtain a molecular anchoring site complex (CoPc MDH) with an M-N4 coordination structure. S2. Mix 50 mg of the molecular anchoring site complex with the M-N4 coordination structure with 15 mL of deionized water, sonicate for 60 min, add 1.20 mL of chloroplatinate (H2PtCl6·6H2O) solution (concentration of 2.0 mg / mL, solvent of deionized water), sonicate for 1 h, stir at 25℃ for 24 h, freeze dry to obtain intermediate product; S3. Under an Ar / H2 atmosphere (Ar:H2=9:1, v / v), the intermediate product was calcined at 400°C for 2 h at a heating rate of 5°C / min to obtain the ultrafine metal nanoparticles (Pt UN-CoPcMDHs) grown based on monomolecular dispersed coordination molecular anchoring.

[0047] The structure of the ultrafine metal nanoparticles grown based on monomolecular dispersed coordination molecular anchoring consists of, from the outside to the inside: ultrafine Pt nanoparticles (≤2 nm), CoPc, and multi-walled carbon nanotubes.

[0048] Figure 1 A schematic diagram of a synthesis method for the controllable growth of ultrafine metal nanoparticles based on monomolecular dispersed coordination molecules is shown.

[0049] Figure 2 The diagram shows a schematic of the synthesis method for controlling the growth of ultrafine Pt nanoparticles based on monomolecular dispersed coordination molecules, as illustrated in Examples 1-3.

[0050] Example 2 A method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth, the method comprising: S1. Mix 150 mg of multi-walled carbon nanotubes with 60 mL of N,N-dimethylformamide (DMF) and sonicate for 80 min; mix 8 mg of FePc with 15 mL of DMF and sonicate for 80 min; mix the two dispersions together and sonicate for 2.5 h, then centrifuge. Wash the centrifuged dispersions with DMF, ethanol, and water, respectively, and freeze-dry to obtain a molecular anchoring site complex (FePc MDH) with an M-N4 coordination structure. S2. Mix 50 mg of the molecular anchoring site complex with the M-N4 coordination structure with 15 mL of deionized water, sonicate for 60 min, add 1.20 mL of chloroplatinate (H2PtCl6·6H2O) solution (concentration of 2.0 mg / mL, solvent of deionized water), sonicate for 1 h, stir at 25℃ for 24 h, freeze dry to obtain intermediate product; S3. Under an Ar / H2 atmosphere (Ar:H2=9:1, v / v), the intermediate product was calcined at 400°C for 2 h at a heating rate of 5°C / min to obtain the ultrafine metal nanoparticles (Pt UN-FePcMDHs) grown based on monomolecular dispersed coordination molecules.

[0051] The structure of the ultrafine metal nanoparticles grown based on monomolecular dispersed coordination molecular anchoring consists of, from the outside to the inside: ultrafine Pt nanoparticles (≤2 nm), FePc, and multi-walled carbon nanotubes.

[0052] Example 3 A method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth, the method comprising: S1. Mix 150 mg of multi-walled carbon nanotubes with 60 mL of N,N-dimethylformamide (DMF) and sonicate for 80 min; mix 8 mg of H2Pc with 15 mL of DMF and sonicate for 80 min; mix the two dispersions together and sonicate for 2.5 h, then centrifuge. Wash the centrifuged dispersions with DMF, ethanol, and water, respectively, and freeze-dry to obtain a molecular anchoring site complex (H2Pc MDH) with an N4 coordination structure. S2. Mix 50 mg of the molecular anchoring site complex with the coordination structure with 15 mL of deionized water, sonicate for 60 min, add 1.20 mL of chloroplatinate (H2PtCl6·6H2O) solution (concentration of 2.0 mg / mL, solvent of deionized water), sonicate for 1 h, stir at 25℃ for 24 h, freeze dry to obtain intermediate product; S3. Under an Ar / H2 atmosphere (Ar:H2=9:1, v / v), the intermediate product was calcined at 400°C for 2 h at a heating rate of 5°C / min to obtain the ultrafine metal nanoparticles (Pt UN-H2PcMDHs) grown based on monomolecular dispersed coordination molecular anchoring.

[0053] The structure of the ultrafine metal nanoparticles based on monomolecular dispersed coordination molecular anchoring growth consists of, from the outside to the inside: ultrafine Pt nanoparticles (≤2 nm), H2Pc, and multi-walled carbon nanotubes.

[0054] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that step S1 is deleted, and the 50 mg molecular anchoring site complex with coordination structure in step S2 is replaced with 50 mg multi-walled carbon nanotubes. The rest is the same as in Example 1, and Pt nanoparticles (Pt / CNTs) are grown based on carbon nanotubes.

[0055] The Pt nanoparticles grown based on carbon nanotubes consist of, from the outside to the inside: Pt nanoparticles and multi-walled carbon nanotubes.

[0056] Figure 3 A schematic diagram of the structure of Pt nanoparticles grown based on carbon nanotubes is shown in Comparative Example 1.

[0057] Test Example 1 The surface morphology of Examples 1-3 and Comparative Example 1 was tested by scanning electron microscopy.

[0058] Test results are as follows Figure 4 As shown.

[0059] Figure 4 The surface morphology scanning electron microscope images of Examples 1-3 and Comparative Example 1 are shown; in, Figure 4 (ai) shows a scanning electron microscope image of the surface morphology of Example 1; Figure 4 (a-ii) in the figure shows scanning electron microscope images of the surface morphology of Example 2; Figure 4 (a-iii) in the figure show scanning electron microscope images of the surface morphology of Example 3; Figure 4(b) shows a scanning electron microscope image of the surface morphology of Comparative Example 1; As can be seen from the above test results, the surface morphology of Examples 1-3 is not significantly different from that of the comparative examples.

[0060] Test Example 2 The microstructures of Examples 1-3 and Comparative Example 1 were tested using double spherical aberration electron microscopy.

[0061] Test results are as follows Figure 5 As shown.

[0062] Figure 5 The microstructure double aberration electron microscope images of Examples 1-3 and Comparative Example 1 are shown; in, Figure 5 Image (a) shows a double spherical aberration electron microscope image of the microstructure of Comparative Example 1; Figure 5 (b) shows a double aberration electron microscope image of the microstructure of Example 1; Figure 5 (c) shows a double aberration electron microscope image of the microstructure of Example 2; Figure 5 Image (d) shows a double aberration electron microscope image of the microstructure of Example 3; The test results above show that the average particle size of the Pt nanoparticles in Comparative Example 1 is 5.6 ± 1 nm, and there is obvious agglomeration; while the average particle sizes of the Pt nanoparticles in Examples 1-3 are 1.4 ± 0.5 nm, 1.5 ± 0.5 nm and 1.8 ± 0.5 nm, respectively, which are smaller, have no obvious agglomeration, and have a uniform particle size distribution.

[0063] Test Example 3 Performance tests of Examples 1-3, Comparative Example 1, and commercial platinum-carbon catalyst (Pt / C) in alkaline electrolyte.

[0064] Test Methods: Electrochemical measurements were performed on an electrochemical workstation (CHI760E, Shanghai Chenhua) using a standard three-electrode configuration with 1.0 M KOH as the electrolyte. A graphite rod was used as the counter electrode, and a saturated calomel electrode (Hg / Hg₂Cl₂, saturated KCl) was used as the reference electrode. 40 μl of catalyst ink (2.5 mg of the sample prepared in the examples or comparatives, or a commercial platinum-carbon catalyst dispersed in 1 mL of ethanol and 20 μL of 5 wt% Nafion solution) was drop-coated to an effective area of ​​0.5 cm². 2 On carbon paper (TGP-H-060, Sinero), 0.2 mg / cm³ was obtained. 2Mass-loaded working electrode. Linear sweep voltammetry (LSV) was used for testing at a scan rate of 5 mV / s. All potentials were converted to the reversible hydrogen electrode (RHE) scale and compensated for 95% ohmic drop (IR). Potential calculation formula: ERHE = E Hg2Cl2 +0.0591×pH-0.95 iR+0.241.

[0065] Test results are as follows Figure 6 As shown.

[0066] Figure 6 Performance test graphs of Examples 1-3, Comparative Example 1, and a commercial platinum-carbon catalyst (Pt / C) in alkaline electrolytes are shown.

[0067] The test results above show that the performance of Example 1 is significantly better than that of Comparative Example 1 and the commercial platinum-carbon catalyst (Pt / C). The performance of Examples 2 and 3 is significantly better than that of Comparative Example 1, but slightly worse than that of the commercial platinum-carbon catalyst (Pt / C). Comparative Example 1 has the worst performance.

[0068] Test Example 4 Industrial-grade long-term stability tests of electro-water were conducted on the device assembled in Example 1 with an electrolytic water membrane.

[0069] Test Method: First, the anion exchange membrane (Fumasep FAA-3-PK-75) was pretreated by immersing it in 1.0 M KOH for 24 h, then rinsed with deionized water and stored in a constant temperature and humidity oven for later use. Catalyst ink was prepared by dispersing 75 mg of finely ground catalyst powder (sample prepared in Example 1) in a mixed solvent consisting of 6 mL ethanol, 0.6 mL ion exchanger (FumionFAA-3-SOLUT-10), and 2.4 mL deionized water. The catalyst ink was stirred for 30 min and ultrasonically treated in a water bath for 1 h; this process was repeated three times to ensure uniform dispersion. The resulting ink was uniformly sprayed onto the pretreated membrane, forming an effective area of ​​5 × 5 cm². 2 The loading capacity is 0.2 mg / cm³. 2 Nickel foam was used as the cathode diffusion layer, nickel-iron hydroxide as the anode, and nickel foam as the anode diffusion layer. After assembly, the cathode was subjected to sequentially controlled tests at -0.2, -0.5, and -1.0 A / cm at room temperature. 2 Electrochemical activation of the membrane device was achieved by running it at a current density of -1.0 A / cm for 1 h until a stable voltage was reached. Then, the assembled membrane device was subjected to electrochemical activation at 40 °C at a current density of -1.0 A / cm. 2 The constant current density was tested using the constant current potential method.

[0070] Test results are as follows Figure 7 As shown.

[0071] Figure 7 The diagram shows the industrial-grade current performance test of the device assembled with the water electrolysis membrane in Example 1.

[0072] The test results above show that Example 1 can operate stably at an industrial-grade current density for more than 200 hours in a membrane device, demonstrating excellent stability.

[0073] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0074] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth, characterized in that, The method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring includes the following steps: S1. Metal-coordinated molecules or metal-free central coordination molecules are immobilized on the surface of a carbon-based conductive carrier in a monomolecular dispersion manner to obtain molecules with MN. x Coordination structure or N x Molecular anchoring site complexes with coordination structures; S2. The molecular anchoring site complex is mixed and reacted with the target metal precursor solution to selectively adsorb and enrich the target metal precursor at the coordination site to obtain the intermediate product. S3. The intermediate product is added to a mixed atmosphere of inert and reducing atmospheres for reduction treatment to obtain the ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth. in, M is selected from one or more of Co, Fe, Ni, Cu, Mn, Cr, and Zn.

2. The method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth according to claim 1, characterized in that, The metal coordination molecule is selected from one or more of metal phthalocyanine, metal porphyrin or their derivatives; The metal-free central coordinating molecule is selected from one or more of metal-free central phthalocyanines and metal-free central porphyrins.

3. The method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth according to claim 1, characterized in that, The single-molecule dispersion method is as follows: a carbon-based conductive carrier is dispersed in a solvent to obtain a carbon-based conductive carrier dispersion, a metal coordination molecule or a metal-free central coordination molecule is dispersed in a solvent to obtain a coordination molecule dispersion, and the carbon-based conductive carrier dispersion and the coordination molecule dispersion are mixed and subjected to ultrasonic dispersion treatment.

4. The method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth according to claim 3, characterized in that, The ultrasonic dispersion time is 1-4 hours.

5. The method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth according to claim 1, characterized in that, The carbon-based conductive carrier is selected from one or more of the following: multi-walled carbon nanotubes, graphene, carbon black, mesoporous carbon, carbon fiber cloth, and carbon paper.

6. The method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth according to claim 1, characterized in that, The mixing reaction involves dispersing the molecular anchoring site complex in a solvent, adding a target metal precursor solution, and then sonicating to obtain an intermediate product.

7. The method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth according to claim 6, characterized in that, The mixing reaction takes 1-3 hours.

8. The method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth according to claim 1, characterized in that, The target metal precursor is selected from one or more salts or complexes of Pt, Pd, Au, Ru, Ir, and Ag.

9. The method for synthesizing ultrafine metal nanoparticles based on monomolecular dispersed coordination molecule anchoring growth according to claim 1, characterized in that, The reduction treatment is performed at a temperature of 200-400℃.

10. The product prepared by the synthesis method of ultrafine metal nanoparticles based on monomolecular dispersed coordination molecular anchoring growth as described in any one of claims 1-9.

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