Electrochemical functionalization modification methods, materials, and electrodes for supported catalysts

Abstract

The application discloses an electrochemical functional modification method of a supported catalyst, a material and an electrode, relates to the cross technical field of new energy materials and high-value utilization of chemical resources, and the method comprises the following steps: pretreating a supported catalyst to obtain a catalyst matrix; uniformly mixing and compounding the catalyst matrix, an organic carbon source and a solid nitrogen source to prepare a precursor composite; placing the precursor composite in an inert or weakly reducing atmosphere, performing multi-stage programmed temperature heating treatment to obtain a pyrolysis product; and performing post-treatment on the pyrolysis product after cooling to obtain an electrochemical functional modification material. The scheme can solve the intrinsic functional defects of the industrial supported catalyst, convert the supported catalyst into a high-performance electrochemical functional modification material, and directly use the material as an electrochemical oxygen electrode, thereby greatly reducing the preparation cost of the oxygen electrode material and being beneficial to large-scale commercial application of electrochemical energy devices.

Description

Technical Field

[0001] This application relates to the interdisciplinary technical field of new energy materials and high-value utilization of chemical resources, and in particular to an electrochemical functionalization modification method, materials and electrodes for supported catalysts. Background Technology

[0002] In the field of electrochemical energy, the slow kinetics of oxygen reduction and oxygen evolution reactions severely restrict the energy conversion efficiency of devices such as fuel cells and metal-air batteries. Although noble metal catalysts such as platinum and iridium exhibit excellent activity, their high cost and scarcity make large-scale commercialization difficult. Therefore, developing low-cost, highly active, and highly stable non-noble metal oxygen electrode catalysts has become a core research focus. In the chemical industry, supported catalysts using transition metals such as nickel, molybdenum, and cobalt as active components and porous materials such as γ-alumina as supports have achieved large-scale industrial applications in processes such as hydrogenation and dehydrogenation, possessing significant advantages such as readily available raw materials and low cost.

[0003] However, these catalysts cannot be directly used as electrochemical oxygen electrodes due to their intrinsic properties, mainly due to the following drawbacks: First, the active component and the support have poor conductivity, making it impossible to construct a fast electron transport channel; second, the channels are mainly micropores, which are not conducive to the wetting of aqueous electrolytes and the mass transfer of gaseous reactants; in addition, the surface active sites are adapted to hydrocarbon reactions, but are inactive for the adsorption and activation of oxygen molecules, and are easily corroded and deactivated under the electrochemical window. Existing technologies mostly synthesize non-precious metal catalysts de novo. Although carbon coating modification has been attempted, the raw material cost is high, and it is difficult to solve the structural and stability problems. Summary of the Invention

[0004] The purpose of this application is to provide a method, material, and electrode for electrochemical functionalization modification of supported catalysts, aiming to solve the technical problem that industrial supported catalysts cannot be directly used as electrochemical oxygen electrodes in the prior art.

[0005] To achieve the above objectives, this application provides a method for electrochemical functionalization modification of supported catalysts, comprising: The supported catalyst is pretreated to obtain a catalyst matrix; wherein the supported catalyst comprises a transition metal active component and a porous support; The catalyst matrix, organic carbon source and solid nitrogen source are uniformly mixed and compounded to prepare the precursor complex; The precursor complex is placed in an inert or weakly reducing atmosphere and subjected to multi-stage programmed temperature rise heat treatment to obtain pyrolysis products; wherein, the pyrolysis products are composite structures with conductive networks, metal-carbon-nitrogen active interfaces, optimized mass transfer structures and rigid skeleton coating functional coatings. The pyrolysis products are cooled and then post-processed to obtain electrochemically functionalized modified materials.

[0006] In one embodiment, the transition metal active component includes at least two of nickel, molybdenum, cobalt, tungsten, iron, manganese, and copper; the porous support includes at least one of γ-alumina, molecular sieve, silica, activated carbon, and diatomaceous earth.

[0007] In one embodiment, the organic carbon source includes at least one of glucose, sucrose, citric acid, starch, phenolic resin, and polyacrylonitrile; the solid nitrogen source includes at least one of urea, melamine, dicyandiamide, polyaniline, and polydopamine.

[0008] In one embodiment, the mass ratio of the catalyst matrix, organic carbon source and solid nitrogen source is 1: (1.0~2.0): (2.0~4.0).

[0009] In one embodiment, the multi-stage programmed temperature rise heat treatment includes a first stage treatment and a second stage treatment. The first stage treatment includes heating to 200°C at a heating rate of 3°C / min and holding at 200°C for 30 minutes. The second stage treatment includes heating to 700~900°C at a heating rate of 5°C / min and holding at 700~900°C for 2 hours.

[0010] In one embodiment, the supported catalyst is pretreated to obtain a catalyst matrix, which includes: sequentially crushing, ball milling and sieving the supported catalyst to obtain a powdered catalyst matrix.

[0011] In one embodiment, the pyrolysis product is cooled and then post-processed, including grinding and sieving the cooled pyrolysis product to obtain a powdered electrochemically functionalized modified material.

[0012] In addition, this application also provides an electrochemically functionalized modified material, which is prepared by the electrochemical functionalization modification method of the supported catalyst described above.

[0013] In one embodiment, the material is a composite structure with a rigid framework coated with a functional coating. The material uses the porous support of the supported catalyst as a rigid framework. The surface and pores of the rigid framework are coated with a nitrogen-doped carbon functional coating, and the surface of the rigid framework has a metal-carbon-nitrogen composite catalytic interface.

[0014] In addition, this application also provides an electrode for an electrochemical energy device, the electrode comprising a catalytically active material, a conductive agent, and a binder; the catalytically active material comprises the electrochemically functionalized modified material as described above.

[0015] The above-mentioned technical solution of this application has at least the following beneficial technical effects: The technical solution of this application, through pretreatment of industrial supported catalysts, carbon-nitrogen source compositing, and multi-stage temperature-controlled pyrolysis, simultaneously constructs a composite structure consisting of a conductive network, a metal-carbon-nitrogen active interface, an optimized mass transfer structure, and a rigid framework coated with a functional coating. This addresses the intrinsic functional defects of industrial supported catalysts, transforming them into high-performance electrochemically functionalized modified materials that can be directly used as electrochemical oxygen electrodes. Furthermore, this method utilizes low-cost industrial catalysts as raw materials, eliminating the need for de novo synthesis of new materials, significantly reducing the preparation cost of oxygen electrode materials. The resulting materials possess high conductivity, abundant catalytic active sites, and excellent structural and chemical stability, which is beneficial for the large-scale commercial application of electrochemical energy devices. Attached Figure Description

[0016] Figure 1 This is a schematic flowchart of an embodiment of the electrochemical functionalization modification method for supported catalysts provided in this application; Figure 2 This is a process flow diagram of a specific embodiment of the electrochemical functionalization modification method for supported catalysts provided in this application; Figure 3 These are the zinc-air battery test polarization curves of the materials prepared in Examples 1-7 and Comparative Examples 1-2; Figure 4 This is a stepped constant current discharge curve of a zinc-air battery assembled with M-Cat samples; Figure 5 The graph shows the constant current discharge curves of the zinc-air battery assembled with the modified material (M-Cat) obtained in Example 1 at current densities of 10 mA / cm² and 50 mA / cm². Figure 6 This is a comparison of scanning electron microscope images of the modified material (M-Cat) obtained in Example 1 and the original commercial catalyst (Original-Cat) in Comparative Example 1. Figure 7 Here are the XPS spectra of M-Cat: (a) full spectrum scan; (b) Ni 2p spectrum; (c) Mo 3d spectrum; (d) O 1s spectrum; (e) C 1s spectrum; (f) N 1s spectrum. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of this application. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0018] The embodiments described in this application are only some, not all, of the embodiments described herein. All other embodiments obtained by those skilled in the art based on the embodiments described herein without inventive effort are within the scope of protection of this application.

[0019] In the field of electrochemical energy, the slow kinetics of oxygen reduction and oxygen evolution reactions severely restrict the energy conversion efficiency of devices such as fuel cells and metal-air batteries. Although noble metal catalysts such as platinum and iridium exhibit excellent activity, their high cost and scarcity make large-scale commercialization difficult. Therefore, developing low-cost, highly active, and highly stable non-noble metal oxygen electrode catalysts has become a core research focus. In the chemical industry, supported catalysts using transition metals such as nickel, molybdenum, and cobalt as active components and porous materials such as γ-alumina as supports have achieved large-scale industrial applications in processes such as hydrogenation and dehydrogenation, possessing significant advantages such as readily available raw materials and low cost.

[0020] However, these catalysts cannot be directly used as electrochemical oxygen electrodes due to their intrinsic properties, mainly due to the following drawbacks: First, the active component and the support have poor conductivity, making it impossible to construct a fast electron transport channel; second, the channels are mainly micropores, which are not conducive to the wetting of aqueous electrolytes and the mass transfer of gaseous reactants; in addition, the surface active sites are adapted to hydrocarbon reactions, but are inactive for the adsorption and activation of oxygen molecules, and are easily corroded and deactivated under the electrochemical window. Existing technologies mostly synthesize non-precious metal catalysts de novo. Although carbon coating modification has been attempted, the raw material cost is high, and it is difficult to solve the structural and stability problems.

[0021] To address the aforementioned technical problems, this application provides an electrochemical functionalization modification method for supported catalysts. By pretreating industrial supported catalysts, combining them with carbon and nitrogen sources, and performing multi-stage temperature-controlled pyrolysis, a composite structure is simultaneously constructed, comprising a conductive network, a metal-carbon-nitrogen active interface, an optimized mass transfer structure, and a rigid framework coated with a functional coating. This method overcomes the intrinsic functional defects of industrial supported catalysts, transforming them into high-performance electrochemically functionalized modified materials that can be directly used as electrochemical oxygen electrodes. Furthermore, this method utilizes low-cost industrial catalysts as raw materials, eliminating the need for de novo synthesis of new materials, significantly reducing the preparation cost of oxygen electrode materials. The resulting materials possess high conductivity, abundant catalytic active sites, and excellent structural and chemical stability, which is beneficial for the large-scale commercial application of electrochemical energy devices.

[0022] In one implementation, please refer to Figure 1 The electrochemical functionalization modification method of this supported catalyst includes the following steps: Step S1: Pretreatment of the supported catalyst to obtain a catalyst matrix; wherein the supported catalyst comprises a transition metal active component and a porous support. Specifically, the transition metal active component includes at least two of nickel, molybdenum, cobalt, tungsten, iron, manganese, and copper; the porous support includes at least one of γ-alumina, molecular sieve, silica, activated carbon, and diatomaceous earth. The pretreatment process of the supported catalyst is as follows: the supported catalyst is sequentially crushed, ball-milled, and sieved to obtain a powdered catalyst matrix. In step S1, commercially available spherical catalysts are selected. Hydrogenated supported catalysts are crushed, ball-milled, and sieved through a 200-mesh sieve to obtain a powdered catalyst matrix. This pretreatment method can refine the catalyst particle size, increase its contact area with the carbon and nitrogen sources, facilitate subsequent uniform compounding, and remove impurities between particles to ensure the purity of the matrix.

[0023] Step S2: The catalyst matrix, organic carbon source, and solid nitrogen source are uniformly mixed and composited to prepare a precursor composite. In one embodiment, the organic carbon source includes at least one of glucose, sucrose, citric acid, starch, phenolic resin, and polyacrylonitrile; the solid nitrogen source includes at least one of urea, melamine, dicyandiamide, polyaniline, and polydopamine. In one embodiment, the mass ratio of the catalyst matrix, organic carbon source, and solid nitrogen source is 1:(1.0~2.0):(2.0~4.0). In this step S2, the catalyst matrix powder and glucose are ball-milled and mixed in a certain proportion, dried to obtain a composite powder, and then uniformly mixed with urea in a mass ratio of 1:(1.0~2.0):(2.0~4.0) to obtain the precursor composite. By precisely controlling the carbon and nitrogen source ratio, a suitable raw material basis can be provided for the subsequent pyrolysis to construct the active interface, and the stepwise composite method allows for more uniform dispersion of each component, avoiding local agglomeration.

[0024] Step S3: Place the precursor composite in an inert or weakly reducing atmosphere and perform a multi-stage programmed temperature heat treatment to obtain a pyrolysis product; wherein the pyrolysis product is a composite structure with a conductive network, a metal-carbon-nitrogen active interface, an optimized mass transfer structure, and a rigid skeleton coating. In one embodiment, the multi-stage programmed temperature heat treatment includes a first stage treatment and a second stage treatment. The first stage treatment includes heating to 200°C at a heating rate of 3°C / min and holding at 200°C for 30 minutes; the second stage treatment includes continuing to heat to 700~900°C at a heating rate of 5°C / min and holding at 700~900°C for 2 hours. In step S3, the precursor complex is spread on a quartz boat and placed in a tube furnace. After replacing the air with high-purity argon, the temperature is first raised to 200°C at 3°C / min and held for 30 minutes, and then raised to 700~900°C at 5°C / min and held for 2 hours. Through this multi-stage temperature-controlled pyrolysis, the construction of the conductive network, the reconstruction of the active interface and the optimization of the mass transfer structure can be achieved simultaneously. The precisely controlled heating rate and temperature avoid structural collapse or aggregation of active components.

[0025] Step S4: After cooling the pyrolysis products, post-processing is performed to obtain the electrochemically functionalized modified material. The post-processing process is as follows: the cooled pyrolysis products are ground and sieved to obtain powdered electrochemically functionalized modified materials. In step S4, the pyrolysis products that have been naturally cooled to room temperature in the tube furnace are taken out, gently ground in an agate mortar, and then sieved through a 200-mesh sieve to obtain powdered electrochemically functionalized modified materials. Through gentle grinding and sieving, modified materials with uniform particle size can be obtained, improving the dispersibility of the material, while avoiding excessive grinding force that may damage the constructed composite structure and ensuring the electrochemical performance of the material.

[0026] In addition, this application also provides an electrochemically functionalized modified material, which is prepared by the electrochemical functionalization modification method of the supported catalyst described above.

[0027] In one embodiment, the material is a composite structure with a rigid framework coated with a functional coating. The material uses a porous support for a supported catalyst as a rigid framework. The surface and pores of the rigid framework are coated with a nitrogen-doped carbon functional coating, and the surface of the rigid framework has a metal-carbon-nitrogen composite catalytic interface.

[0028] The technical solution of this application will be further described below with reference to specific embodiments.

[0029] Example 1: Electrochemically Functionalized Modified Materials Please see Figure 2 Example 1 provides an electrochemical functionalization modification method for a supported catalyst, which specifically includes the following steps: Step A1, Precursor Preparation. Take 10g of commercially available spherical... The hydrogenation catalyst was crushed, ball-milled, and sieved through a 200-mesh sieve to obtain a catalyst matrix powder. 2.0 g of the matrix powder was weighed and placed in a ball mill jar with 2.0 g of glucose. Anhydrous ethanol was added, and the mixture was ball-milled at 300 rpm for 6 hours. After separating the zirconia balls, the slurry was dried at 60°C for 24 hours to obtain a catalyst-glucose composite powder. 2.0 g of the composite powder (containing 1.0 g of catalyst and 1.0 g of glucose) was weighed and mixed with 3.0 g of urea powder in a 1:1:3 ratio to obtain a light green precursor.

[0030] Step A2, High-Temperature Pyrolysis. Loosely spread the precursor in a quartz boat and place it in the isothermal zone of a tube furnace. Purge with high-purity argon gas (200 mL / min) for 30 minutes to fully displace the air in the furnace, then adjust the gas flow to 50 mL / min and maintain it. Execute the heating program: increase the temperature from room temperature to 200°C at 3°C / min and hold for 30 minutes; then increase the temperature to 800°C at 5°C / min and hold for 2 hours. After the program is complete, allow it to cool naturally to room temperature under a continuous argon flow.

[0031] Step A3, Post-processing. Remove the quartz boat to obtain a black blocky product. Gently grind it in an agate mortar and pass it through a 200-mesh sieve to obtain the final functionalized modified material, denoted as M-Cat.

[0032] Example 2: Compared with Example 1, the only difference is that the mass ratio of catalyst: glucose: urea is 1:2:3.

[0033] Example 3: Compared with Example 1, the only difference is that the mass ratio of catalyst: glucose: urea is 1:3:3.

[0034] Example 4: Compared with Example 1, the only difference is that the mass ratio of catalyst: glucose: urea is 1:1:2.

[0035] Example 5: Compared with Example 1, the only difference is that the mass ratio of catalyst: glucose: urea is 1:1:4.

[0036] Example 6: Compared with Example 1, the only difference is that the pyrolysis temperature is 700°C.

[0037] Example 7: Compared with Example 1, the only difference is that the pyrolysis temperature is 900°C.

[0038] Example 8: Compared with Example 1, the only difference is that the pyrolysis temperature is 1000°C.

[0039] Comparative Example 1: Original Commercial Supported Catalyst Commercial products in the same batch The catalyst is only subjected to crushing, ball milling, and sieving through a 200-mesh sieve, without any carbon-nitrogen recombination or pyrolysis, and is designated as Original-Cat.

[0040] Comparative Example 2: Framework-less carbon and nitrogen reference sample Without the addition of a commercially available supported catalyst, glucose and urea were prepared using the method described in Example 1, denoted as C&N.

[0041] Furthermore, this application also provides an electrode for an electrochemical energy device, comprising a catalytically active material, a conductive agent, and a binder. The catalytically active material includes the electrochemically functionalized modified material mentioned above. The electrode preparation and zinc-air battery assembly process are as follows: The above materials (M-Cat, Original-Cat) are used as active materials, respectively, and mixed at a ratio of 15 mg of active material, 5 mg of conductive carbon black (acetylene black), and 1 μL of Nafion. Ethanol is added and the mixture is ultrasonically treated to form a uniform slurry. The slurry is coated onto nickel foam using a blade coating method. After the coated electrode is dried at room temperature, it is cut to the required size to serve as an air cathode. A polished zinc sheet is used as the anode. An aqueous solution was used as the electrolyte, and a liquid zinc-air battery was assembled in a standard open-type battery test cell.

[0042] The performance test and comparative analysis of the electrode are as follows: (1) Comparison test of discharge polarization curves To preliminarily evaluate and screen various materials from the perspectives of power output capability and reaction kinetics, the polarization curves of the materials prepared by the samples of Examples 1-7, Comparative Example 1 (Original-Cat), and Comparative Example 2 (C&N) were first tested. The test results are as follows: Figure 3 As shown in the figure. The samples and performance characteristics corresponding to each curve are shown in Table 1.

[0043] Table 1. Preparation conditions and performance characteristics of each embodiment Combination Figure 3 As can be seen from the polarization curves and Table 1: Effect of carbon source ratio: Under the condition that the pyrolysis temperature is 800℃, as the carbon source ratio increases from 1 to 3 (Examples 1-3), the catalytic activity shows a trend of first being optimal and then decreasing. Among them, Example 1 (1:1:3) has the best performance; the activity of Example 2 (1:2:3) begins to decrease; and the activity of Example 3 (1:3:3) further decreases due to the excessive carbon layer. This indicates that the preferred carbon source ratio is 1.0-2.5, with 1.0 being optimal.

[0044] Effect of nitrogen source ratio: Under the conditions of a carbon source ratio of 1 and a pyrolysis temperature of 800°C, as the nitrogen source ratio increased from 2 to 4 (Examples 1, 4, and 5), the catalytic activity reached its optimum at a ratio of 3. The performance of Example 4 (1:1:2) decreased, indicating that an active interface could not be sufficiently constructed when the nitrogen source ratio was below 2; the performance of Example 5 (1:1:4) also decreased, indicating that excessive nitrogen source may lead to over-etching. Therefore, the preferred nitrogen source ratio is 2.0-4.0, with 3.0 being optimal.

[0045] Effect of pyrolysis temperature: At a 1:1:3 ratio, the pyrolysis temperature significantly affects performance. Example 6 (700℃) showed incomplete carbonization and decreased performance due to the low temperature; Example 1 (800℃) exhibited the best performance; Example 7 (900℃) showed slightly lower activity but still good; Example 8 (1000℃) showed a significant decrease in activity due to excessively high temperature leading to metal agglomeration or excessive graphitization of the carbon layer. Therefore, the preferred pyrolysis temperature is 700-900℃, with 800℃ being optimal.

[0046] To evaluate the power output capability of different materials, the discharge polarization curves of the original catalyst (Original-Cat), the framework-free carbon and nitrogen reference sample (C&N), and the sample of this invention (M-Cat) were tested. The results are as follows: Figure 3 As shown in Table 2.

[0047] Table 2 Comparison of electrochemical performance of each sample Combination Figure 3 As shown in Table 2, the original catalyst is essentially electrochemically inert and has almost no effective output capability. Although the framework-less reference sample gains slight activity due to the presence of the carbon-nitrogen layer, its performance improvement is limited by its easily collapsible structure. The sample of this invention maintains a high and stable discharge voltage over a wide current range, with a maximum discharge current density of 400 mA / cm², far exceeding that of the control group. This comparison clearly demonstrates that the superior power characteristics of this invention depend on a "rigid"... The synergistic construction of the "skeleton" and the "carbon-nitrogen functional layer" is indispensable in terms of both structural support and activity regulation.

[0048] (2) Stepped discharge performance test Wide current range stepped discharge and high rate performance: To evaluate the material's response capability and structural stability under high load, stepped constant current discharge tests were performed on M-Cat assembled batteries. Figure 4As shown, the current density started at 5 mA / cm² and increased in stepwise increments of 10 mA / cm² up to 100 mA / cm², with continuous discharge for 1 hour at each current density. The test results demonstrate that the material exhibits excellent stability across the entire wide current range from 5 mA / cm² to 100 mA / cm²: at each current step, the battery rapidly reaches and maintains a stable discharge voltage plateau; as the current density increases to 100 mA / cm², the voltage plateau decreases smoothly without drastic fluctuations or instantaneous collapse, proving its superior high-rate discharge capability. This result fully demonstrates that the material of this invention possesses excellent high-rate performance, rapid kinetic response, and superior structural and electrochemical stability at high current densities (up to 100 mA / cm²), enabling it to meet the demands of high-power loads.

[0049] (3) Constant current discharge performance test To further evaluate the material's continuous operating capability and lifespan under different current loads, a series of constant current discharge tests were conducted on the M-Cat assembled battery. The results are as follows: Figure 5 As shown: At a practical current density of 10 mA / cm², the battery can continuously and stably discharge for up to 160 hours (approximately 7 days) until the zinc active material is completely consumed, thus terminating the test and verifying its ultra-long lifespan and reliability within the typical operating range.

[0050] At a high current density of 50 mA / cm², the battery can continuously and stably discharge for 65 hours, demonstrating its ability to withstand continuous high power output.

[0051] The above series of tests demonstrate that the material of this invention exhibits excellent long-term operational stability across a wide current range, from low to high. Its unique "rigid skeleton@functional coating" structure effectively resists structural stress and chemical corrosion caused by prolonged electrochemical operation, which is the fundamental reason for its ultra-long service life.

[0052] (4) Physical structure characterization SEM analysis: such as Figure 6 As shown, M-Cat particles with a diameter of tens of micrometers are coated with a uniform carbon-nitrogen layer on their surface and in their channels. From Figure 6As can be seen, the surface of this carbon-nitrogen layer exhibits a nanoscale fibrous network structure. This unique surface morphology has multiple positive effects on improving electrochemical performance: First, the fibrous network structure significantly increases the specific surface area of ​​the material, providing a richer active interface for electrochemical reactions; second, this network structure facilitates the wetting and penetration of the electrolyte, promoting the rapid transport of reactants (oxygen) and products (hydroxyl ions); in addition, the continuous carbon-nitrogen network itself constitutes a highly efficient electron conduction network, ensuring rapid charge transfer during the electrochemical reaction process. These structural features collectively explain the excellent discharge performance and rate characteristics exhibited by M-Cat in zinc-air batteries. In contrast, the surface of the unmodified Original-Cat consists of continuous, smooth alumina carrier particles with nickel-molybdenum metal particles attached, without a significant carbonaceous coating layer or nanoscale rough structure.

[0053] XPS analysis: such as Figure 7 As shown, full-spectrum scanning confirmed the presence of C, N, O, Ni, Mo, and a support in the sample. The Al element was detected without any impurity peaks. High-resolution spectral analysis showed that the Mo 3d spectrum exhibited typical peaks at 232.8 eV and 235.9 eV. Twin Peaks The Ni 2p spectrum shows a main peak at 856.5 eV, accompanied by characteristic satellite peaks at 862.2 eV and 880.9 eV, confirming that Ni exhibits high spin characteristics. The metal exists in the form of hydroxides / hydroxyoxides; the O 1s spectrum is dominated by a metallic hydroxyl (M–OH) peak at 531.5 eV, and the absence of a lattice oxygen peak at 529.5 eV indicates that the metal species are in a highly dispersed amorphous state; the N 1s spectrum can be fitted to three components, which are attributed to graphitic nitrogen (400.6 eV), pyridine nitrogen / metal-nitrogen coordination bonds (398.6 eV), and a small amount of nitride species (396.8 eV), confirming that nitrogen has been successfully incorporated into the carbon framework and interacts with the metal; the C 1s spectrum is dominated by a peak at 284.8 eV. Carbon was the dominant peak, and C–N / C–O bonds (285.6 eV) and a weak [unclear text - possibly a typo, should be "carbon" or "carbon"]. The satellite peak (~291 eV) indicates the formation of a nitrogen-doped carbon coating layer. These results collectively confirm the successful construction of a highly dispersed carbon network anchored by a nitrogen-doped carbon network. A complex structure of active hydroxyl oxide sites.

[0054] The above embodiments detail the commercial application. The process of catalyst modification and its successful application in zinc-air batteries, and its excellent results. Those skilled in the art will understand that the modification method provided by this invention has universality. The core of the method lies in fully utilizing the inherent high-strength porous support in industrial supported catalysts as a rigid framework, and constructing a "carbon-nitrogen functional coating" on its surface and within its pores through a specific process. This forms a stable composite structure where the framework support and the functional coating synergistically enhance each other, systematically solving the defects in conductivity, catalytic activity, and stability of such materials when used as electrodes.

[0055] Therefore, this method is expected to be applicable to the modification of commercially supported catalysts in other metal systems (such as Co, Mo, Fe, W-based, etc.); the resulting functionalized materials are also suitable for constructing electrodes that rely on highly efficient oxygen catalytic reactions, such as other types of metal-air batteries and fuel cell cathodes. These applications can all be achieved through conventional electrode processes, depending on the specific requirements of the target device.

[0056] This application aims to protect a method, material, and electrode for the electrochemical functionalization modification of supported catalysts. The technical solution of this application involves pretreatment of industrial supported catalysts, carbon-nitrogen source compositing, and multi-stage temperature-controlled pyrolysis. This simultaneously constructs a composite structure consisting of a conductive network, a metal-carbon-nitrogen active interface, an optimized mass transfer structure, and a rigid framework coated with a functional coating. This addresses the intrinsic functional defects of industrial supported catalysts, transforming them into high-performance electrochemically functionalized modified materials that can be directly used as electrochemical oxygen electrodes. Furthermore, this method utilizes low-cost industrial catalysts as raw materials, eliminating the need for de novo synthesis of new materials, significantly reducing the preparation cost of oxygen electrode materials. The resulting materials possess high conductivity, abundant catalytic active sites, and excellent structural and chemical stability, which is beneficial for the large-scale commercial application of electrochemical energy devices.

[0057] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of this application and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of this application should be included within the protection scope of this application. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. A method for electrochemical functionalization modification of a supported catalyst, characterized in that, include: The supported catalyst is pretreated to obtain a catalyst matrix; wherein the supported catalyst comprises a transition metal active component and a porous support; The catalyst matrix, organic carbon source and solid nitrogen source are uniformly mixed and compounded to prepare the precursor complex; The precursor complex is placed in an inert or weakly reducing atmosphere and subjected to multi-stage programmed temperature rise heat treatment to obtain pyrolysis products; wherein, the pyrolysis products are composite structures with conductive networks, metal-carbon-nitrogen active interfaces, optimized mass transfer structures and rigid skeleton coating functional coatings. The pyrolysis products are cooled and then post-processed to obtain electrochemically functionalized modified materials.

2. The method for electrochemical functionalization modification of the supported catalyst according to claim 1, characterized in that, The transition metal active component includes at least two of nickel, molybdenum, cobalt, tungsten, iron, manganese, and copper; the porous support includes at least one of γ-alumina, molecular sieve, silica, activated carbon, and diatomaceous earth.

3. The method for electrochemical functionalization modification of the supported catalyst according to claim 1, characterized in that, The organic carbon source includes at least one of glucose, sucrose, citric acid, starch, phenolic resin, and polyacrylonitrile; the solid nitrogen source includes at least one of urea, melamine, dicyandiamide, polyaniline, and polydopamine.

4. The method for electrochemical functionalization modification of the supported catalyst according to claim 3, characterized in that, The mass ratio of the catalyst matrix, organic carbon source and solid nitrogen source is 1: (1.0~2.0): (2.0~4.0).

5. The method for electrochemical functionalization modification of the supported catalyst according to claim 1, characterized in that, The multi-stage programmed temperature rise heat treatment includes a first stage treatment and a second stage treatment. The first stage treatment includes heating to 200°C at a heating rate of 3°C / min and holding at 200°C for 30 minutes. The second stage treatment includes heating to 700~900°C at a heating rate of 5°C / min and holding at 700~900°C for 2 hours.

6. The method for electrochemical functionalization modification of the supported catalyst according to claim 1, characterized in that, Pretreatment of the supported catalyst to obtain a catalyst matrix includes: sequentially crushing, ball milling and sieving the supported catalyst to obtain a powdered catalyst matrix.

7. The method for electrochemical functionalization modification of the supported catalyst according to claim 1, characterized in that, The pyrolysis products are cooled and then post-processed, including grinding and sieving the cooled pyrolysis products to obtain powdered electrochemical functionalized modified materials.

8. An electrochemically functionalized modified material, characterized in that, It is prepared by the electrochemical functionalization modification method of the supported catalyst according to any one of claims 1 to 7.

9. The electrochemically functionalized modified material according to claim 8, characterized in that, The material is a composite structure with a rigid framework and a functional coating. The material uses the porous support of the supported catalyst as a rigid framework. The surface and pores of the rigid framework are coated with a nitrogen-doped carbon functional coating, and the surface of the rigid framework has a metal-carbon-nitrogen composite catalytic interface.

10. An electrode for an electrochemical energy device, characterized in that, The electrode comprises a catalytically active material, a conductive agent, and a binder; the catalytically active material comprises the electrochemically functionalized modified material as described in claim 8 or 9.

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