A C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst derived from MOF material and its preparation method

Abstract

This invention discloses a MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst. The MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst is composed of Cu and Cu₂O supports, Pd particles, and high specific surface area Pd-Cu flowers. In the C@Cu-Pd catalyst, C@Cu not only serves as a support to disperse Pd particles and prevent aggregation, but the Cu in the support can also interact with Pd to form high specific surface area Pd-Cu flowers. This results in a more uniform dispersion of Cu within the support, constrained by the original framework structure. Furthermore, the growth of high specific surface area Pd-Cu flower structures on the Cu support surface via a simple chemical reduction method increases the specific surface area of ​​the material, thereby increasing the effective active surface area of ​​the catalyst and improving its electrocatalytic hydrogen evolution activity.

Description

Technical Field

[0001] This invention relates to the field of electrocatalytic chemistry, specifically to a high specific surface area Pd-Cu hydrogen evolution catalyst derived from MOF material and its preparation method. Background Technology

[0002] With the continuous development of industrialization, the demand for fossil fuels from large-scale industries has further expanded. However, the non-renewable nature of fossil fuels and the environmental pollution caused by their combustion severely restrict the sustainable development of human society, making the development of clean and sustainable energy urgently needed. Electrolysis of water to produce hydrogen holds promise as an effective and clean alternative to traditional fossil fuels. In the process of water electrolysis, a catalyst is needed to reduce the high overpotential and improve electrolysis efficiency and energy conversion rate. Although platinum (Pt) has high catalytic activity for the hydrogen evolution reaction (HER), its limited reserves on Earth and high cost restrict its widespread industrial application. To improve the utilization rate of HER, it is essential to develop a low-cost, durable, and efficient electrocatalyst that can meet future practical applications.

[0003] In existing research, metal-organic framework (MOF)-derived carbon nanomaterials have been shown to possess high specific surface area, large pore volume, suitable thermal and chemical stability, and good electrical conductivity. This makes them suitable as supports for electrocatalyst preparation, effectively suppressing nanomaterial aggregation. The introduction of supports can effectively limit the size and spatial distribution of metal nanoparticles, enhancing their stability and environmental adaptability. MOF-199 (also known as HKUST-1), a stable octporous cage structure composed of copper clusters interconnected by trimesic acid, is highly suitable for the derivation and preparation of noble metal-based electrocatalyst supports.

[0004] Meanwhile, based on Hammer and Nørskov's d-band center theory, Cu can be used as an ideal alloying element for Pd to lower its d-band center relative to its Fermi level or alter the binding strength of adsorbates on the catalyst surface. Loading nano-Pd particles onto the surface of porous carbon materials derived from MOF-199 not only stabilizes the Pd nanoparticles but also modulates the electronic structure and adsorption properties of the noble metal particles, further enhancing the catalytic performance of Pd nanoparticles.

[0005] The morphology and structure of the supporting material or nanoparticles can significantly affect the electrochemical performance of catalysts. Catalysts with structures such as micro / nanoleaf, nanoflower, nanowire, layered hollow microspheres, and flower / grass-like structures have been reported in the literature. High specific surface area nanocatalysts can be obtained by changing the morphology of the nanoparticle loading method, thereby further improving the electrocatalytic hydrogen evolution performance of the catalyst. Pd-Cu nanocatalysts with different morphologies and structures have also been successfully prepared. For example, CN 114471615 A ​​reports the preparation of a Pd-Cu nano-urchin structure catalyst using ionic liquids in an aqueous system. Zhulan Gu et al. obtained a Pd-Cu nanoflower structure catalyst by heating and stirring in an ethylene glycol aqueous system at 85°C for 6 h using the colloidal stabilizer PVP and some inorganic additives. In known reported work, Pd-Cu nanoflower structures are partially grown on the surface of hollow nanospheres, partially obtained by using a large amount of organic and inorganic additives to assist in the formation of flower structures, or prepared through long-term high-temperature and high-pressure reactions. The above-mentioned catalyst preparation process not only increases energy consumption and causes environmental pollution, but also makes the catalyst preparation process extremely dangerous.

[0006] Therefore, it is of great significance to develop a simple and effective preparation method to achieve stable growth of layered flower-like Pd-Cu nanostructure catalysts on the surface of porous carbon materials derived from MOF-199. Summary of the Invention

[0007] In order to solve one or more technical problems existing in the prior art, one of the objectives of this application is to provide a method for preparing a C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst derived from MOF material, which is simple, mild and easy to control, and the resulting catalyst has a stable structure.

[0008] The second objective of this application is to provide a C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst derived from MOF material, which has good electrocatalytic hydrogen evolution reaction activity and stability.

[0009] To address the aforementioned technical problems, one of the objectives of this application is achieved through the following technical solution:

[0010] A method for preparing a MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst, comprising: A1, preparing a MOF-derived C@Cu support: adding an organic ligand and a supporting electrolyte to an electrolyte, using copper sheets of equal area as the anode and cathode respectively in an electrochemical method, the copper ions obtained by electrolysis effectively bond with the organic ligand in the electrolyte to prepare MOF-199 material, and obtaining MOF-derived C@Cu support material after pyrolysis; A2, preparing C@Cu / GCE: dispersing C@Cu porous carbon nanomaterials in a Nafion ethanol solution, a mixed solution of ethanol and deionized water to form a suspension, and drop-coating the suspension onto a clean glassy carbon electrode surface. Afterwards, C@Cu / GCE was obtained by standing and drying at room temperature; A3. Activation of C@Cu / GCE: A three-electrode system was constructed using C@Cu / GCE as the working electrode, a platinum sheet as the counter electrode, and a saturated calomel electrode as the reference electrode. The surface of C@Cu / GCE was activated by cyclic voltammetry in 0.1 mol / L H2SO4 solution; A4. Preparation of high specific surface area C@Cu-Pd / GCE: The activated C@Cu / GCE was immersed in a mixed solution of PdCl2, sodium dodecyl sulfonate, and H2SO4 for 25 min to prepare C@Cu-Pd / GCE with high specific surface area Pd-Cu flowers on the surface.

[0011] Preferably, the organic ligand is pyromellitic acid.

[0012] Preferably, the MOF-199 material is prepared by continuously applying a constant voltage of 12V for 1.5 hours.

[0013] Preferably, the pyrolysis in step A1 involves heating the organic linker to 500°C at a rate of 2°C / min under a N2 atmosphere for 30 minutes, followed by further carbonization at 900°C for 6 hours.

[0014] Preferably, the suspension C@Cu is prepared by mixing and dispersing 60 μL of 50% Nafion ethanol solution, 125 μL of ethanol, 375 μL of deionized water, and 40 mg of C@Cu powder.

[0015] Preferably, the volume of the C@Cu porous nanocarbon material suspension dropped onto the surface of the clean glassy carbon electrode is 6 μL.

[0016] Preferably, the cyclic voltammetry in step A3 involves scanning three times at a scan rate of 50 mV / s within a potential range of -0.4 to 0.8 V to activate the C@Cu / GCE surface.

[0017] Preferably, the concentrations of PdCl2 and sodium dodecyl sulfonate in a 0.1 mol / L H2SO4 solution are both 12.5 mmol / L.

[0018] The second objective of this application is achieved through the following technical solution:

[0019] A MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst is disclosed. The MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst is composed of Cu and Cu2O support, Pd particles, and high specific surface area Pd-Cu flowers. In the C@Cu-Pd catalyst, C@Cu not only serves as a support to disperse Pd particles and prevent aggregation, but Cu in the support can also interact with Pd to form high specific surface area Pd-Cu flowers.

[0020] Preferably, the MOF-derived C@Cu-Pd catalyst exhibits performance at 10 mA•cm⁻¹ in the electrochemical hydrogen evolution reaction. -2 The overpotential at the current density is 110mV.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] A high specific surface area Pd-Cu flower structure is grown on the surface of MOF-derived C@Cu porous carbon nanocarrier using a simple chemical reduction method. The MOF-derived C@Cu porous carbon nanocarrier is obtained by electrochemical preparation of MOF-199 followed by pyrolysis. The electrode surface is electrochemically activated and then subjected to simple chemical reduction. This invention provides a simple, mild, and easy-to-control method for preparing catalysts, and the resulting catalyst has a stable structure.

[0023] The C@Cu porous carbon nanofiber catalyst support, constrained by the MOF-199 material, restricts the spatial position and size of Cu particles within the original framework structure, resulting in more uniform dispersion and maintaining a homogeneous and highly dispersed state during the reaction. Simultaneously, in this C@Cu-Pd nanocatalyst, a high specific surface area Pd-Cu flower structure is grown on the Cu support surface via a simple chemical reduction method, increasing the material's specific surface area and thus the effective active surface area of ​​the catalyst. This enhances the catalyst's electrocatalytic hydrogen evolution activity. C@Cu not only effectively disperses Pd particles as a support, preventing aggregation, but the Cu particles within the support also interact with Pd, resulting in excellent electrocatalytic hydrogen evolution reaction activity and stability. Attached Figure Description

[0024] Figure 1 Images (a) and (b) are SEM images of Example 2 of this invention;

[0025] Figure 2 This is the SEM image of Comparative Example 2 in this invention;

[0026] Figure 3 For Cu and Pd elements in Figure 1 b. Surface element distribution diagram;

[0027] Figure 4 The electrocatalytic hydrogen evolution activity evaluation graphs (electrochemical linear voltammetry scans of C@Cu / GCE in 1 M KOH) of the catalysts obtained in Comparative Example 1, Comparative Example 2, Example 1, Example 2 and Example 3 of this invention are shown.

[0028] Figure 5 The images show the XRD patterns of the catalysts obtained in Comparative Example 1 and Example 2 of this invention. Detailed Implementation

[0029] The present application will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0030] In the description of this application, it should be understood that the terms "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0031] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0032] A method for preparing a high specific surface area Pd (palladium)-Cu (copper) hydrogen evolution catalyst (C@Cu-Pd) supported on a MOF (metal-organic framework) material-derived C@Cu (copper nanoporous carbon material), the method comprising: A1, preparing a MOF-derived C@Cu support: adding an organic ligand and a supporting electrolyte to an electrolyte, using copper sheets of equal area as the anode and cathode respectively in an electrochemical method, the copper ions obtained by electrolysis are effectively bonded to the organic ligand in the electrolyte to prepare a MOF-199 material, the MOF-199 material is prepared by continuous energization at a constant voltage of 12V for 1.5 hours, and after pyrolysis, the MOF-derived C@Cu support material is obtained; the organic ligand is pyromellitic acid; the pyrolysis is carried out under a N2 atmosphere at a heating rate of 2℃ / min to 500℃ to pyrolyze the organic linker for 30 min, and then further carbonizing at the same rate to 900℃ for 6 h; A2, Preparation of C@Cu / GCE: C@Cu porous carbon nanomaterials were dispersed in a mixed solution of Nafion ethanol, ethanol, and deionized water to form a suspension. The C@Cu suspension was prepared by mixing and dispersing 60 μL of 50% (v / v) Nafion ethanol solution, 125 μL of ethanol, 375 μL of deionized water, and 40 mg of C@Cu powder. The suspension was drop-coated onto a clean glassy carbon electrode surface and allowed to dry at room temperature to obtain C@Cu / GCE. The volume of the C@Cu porous carbon nanomaterial suspension drop-coated onto the clean glassy carbon electrode surface was 6 μL. A3. Activation of C@Cu / GCE: A three-electrode system was constructed using C@Cu / GCE as the working electrode, a platinum sheet as the counter electrode, and a saturated calomel electrode as the reference electrode. The C@Cu / GCE surface was activated using cyclic voltammetry with a mol / L H2SO4 solution. The cyclic voltammetry involved scanning three times at a scan rate of 50 mV / s within a potential range of -0.4 to 0.8 V to activate the C@Cu / GCE surface. A4. Preparation of high specific surface area C@Cu-Pd / GCE: The activated C@Cu / GCE was immersed in a mixed solution of PdCl2, sodium dodecyl sulfonate, and H2SO4 for 25 min to obtain C@Cu-Pd / GCE with high specific surface area Pd-Cu flowers on the surface. The concentrations of PdCl2 and sodium dodecyl sulfonate in the 0.1 mol / L H2SO4 solution were both 12.5 mmol / L.

[0033] Example 1

[0034] The first step involved preparing the precursor MOF-199 material using an electrochemical method. In the electrochemical synthesis of MOF-199, two copper sheets of equal area (2 × 4 cm) were used as the anode and cathode, respectively. The copper sheets were coated with insulating adhesive to maintain an immersion area of ​​4 cm² in the solution. 2Dissolve 0.1M organic linker pyromellitic acid (H3BTC) and 0.1M supporting electrolyte tetrabutylammonium tetrafluoroborate (TBATFB) in 50 ml of methanol solution in an electrolytic cell and stir for 15 minutes to achieve complete dispersion.

[0035] The second step involves continuously energizing the electrolytic cell at a constant voltage of 12V for 1.5 hours. After the reaction is complete, a sky-blue flocculent precipitate of MOF-199 is collected from the electrolytic cell. The obtained flocculent precipitate is washed with methanol and deionized water, respectively, and finally dried in a vacuum oven at 80℃ for 6 hours to obtain the blue MOF-199 precipitate. Compared with the traditional chemical method for preparing MOF-199 crystals, the MOF-199 material prepared by the electrochemical method initially presents as flocculent material with more uniform Cu dispersion.

[0036] The third step involves preparing C@Cu porous carbon nanomaterials using a high-temperature carbonization method under a nitrogen atmosphere. The dried MOF-199 material is evenly spread in a covered alumina-corundum crucible, which is then transferred to a quartz tube in a tube furnace. Air is purged using a stable N2 flow for 30 minutes, and the furnace temperature is increased to 550°C at a rate of 2°C / min to pyrolyze the organic linker and supporting electrolyte in MOF-199. The temperature is then further increased to 900°C at a rate of 2°C / min under a nitrogen atmosphere for 6 hours to achieve further carbonization. Due to the influence of the precursor framework structure, the C@Cu porous carbon nanomaterials prepared at this stage exhibit high Cu dispersion and an increased number of exposed active sites.

[0037] Step 4: Prepare a suspension of C@Cu porous carbon nanomaterials using Nafion solution. Collect the black powder obtained after carbonization; this is the C@Cu porous carbon nanomaterial. Mix 60 μL of 50% Nafion ethanol solution, 125 μL of ethanol, and 375 μL of deionized water thoroughly and let stand. Take 40 mg of C@Cu powder and mix it with the above mixture. Disperse thoroughly using a shaker and then sonicate for 20 minutes.

[0038] Step 5: Polish the 4mm diameter glassy carbon electrode to a mirror finish using an Al2O3 suspension on a polishing machine. After ultrasonic cleaning with deionized water for 5 minutes, allow it to stand and air dry. Use a pipette to drop 6μL of C@Cu suspension onto the pretreated glassy carbon electrode surface and allow it to air dry at room temperature to form a film, thus obtaining C@Cu / GCE.

[0039] Step 6: After immersing the electrode in a 0.1 mol / L H₂SO₄ solution for 5 minutes, a three-electrode system was constructed using C@Cu / GCE as the working electrode, a platinum sheet as the counter electrode, and a saturated calomel electrode as the reference electrode. Cyclic voltammetry was used to activate the electrode surface by scanning at a rate of 50 mV / s for 3 cycles within a potential range of -0.4 to 0.8 V. The activated electrode surface exposed more active sites, which is beneficial for the subsequent formation of the layered flower-like Pd-Cu nanophase.

[0040] Step 7: Pour 0.25 mmol of PdCl2 and 0.25 mmol of sodium dodecyl sulfate (SDS) into 20 mL of a 0.1 mol / L H2SO4 mixed solution and stir thoroughly until homogeneous. Immerse the activated C@Cu / GCE in the mixed solution, ensuring the solution completely covers the modified electrode surface, and remove after 25 minutes. After standing and air drying, the C@Cu-Pd modified glassy carbon electrode is obtained, denoted as C@Cu-Pd / GCE. At this point, the Pd-Cu nanophase on the electrode surface exhibits a layered flower-like structure.

[0041] A MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst was prepared by the above method. The MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst is composed of Cu and Cu₂O supports, Pd particles, and high specific surface area Pd-Cu flowers. In the C@Cu-Pd catalyst, C@Cu not only serves as a support to disperse Pd particles and prevent aggregation, but the Cu in the support can also interact with Pd to form high specific surface area Pd-Cu flowers. The MOF-derived C@Cu-Pd catalyst exhibits high specific surface area at 10 mA•cm⁻¹ in the electrochemical hydrogen evolution reaction. -2 The overpotential at the current density is 110mV.

[0042] Example 2

[0043] The main difference between this embodiment and Embodiment 1 is that the electrode immersion time is 10 minutes, while the remaining steps are the same as in Embodiment 1.

[0044] Example 3

[0045] The main difference between this embodiment and Embodiment 1 is that the electrode immersion time is 50 minutes, while the remaining steps are the same as in Embodiment 1.

[0046] The following are examples of comparisons:

[0047] The glassy carbon electrodes used in the comparative examples and embodiments of this invention all have a diameter of 4 mm; the C@Cu suspension was prepared by mixing 40 mg C@Cu, 60 μL of 50% Nafion ethanol solution, 125 μL of ethanol and 375 μL of deionized water.

[0048] Comparative Example 1

[0049] Two copper sheets of equal area (2×4 cm) were used as the anode and cathode, respectively. The copper sheets were covered with insulating glue so that the area of ​​each copper sheet immersed in the solution remained at 4 cm². 2 0.1M BTC and 0.1M TBATFB were dissolved in 50ml of methanol solution in an electrolytic cell and stirred for 15 minutes to ensure complete dispersion. The electrolytic cell was continuously energized at a constant voltage of 12V for 1.5 hours. After the reaction was completed, a sky-blue flocculent precipitate of MOF-199 was collected from the electrolytic cell. The obtained flocculent precipitate was washed and dried in a vacuum oven at 80℃ for 6 hours to obtain a blue precipitate of MOF-199. The dried MOF-199 material was evenly spread in a covered alumina corundum crucible and transferred to a quartz tube in a tube furnace. Air was purged using a stable N2 flow for 30 minutes, and then the furnace temperature was raised to 550℃, held for half an hour, and then further raised to 900℃. The temperature was maintained at 900℃ for 6 hours to achieve further carbonization, obtaining C@Cu nanoporous carbon material. After dropwise coating 6 μL of C@Cu suspension onto the clean glassy carbon electrode surface, the film is dried at room temperature to obtain C@Cu / GCE.

[0050] Comparative Example 2

[0051] Two copper sheets of equal area (2×4 cm) were used as the anode and cathode, respectively. The copper sheets were covered with insulating glue so that the area of ​​each copper sheet immersed in the solution remained at 4 cm². 20.1M BTC and 0.1M TBATFB were dissolved in 50ml of methanol solution in an electrolytic cell and stirred for 15 minutes to ensure complete dispersion. The electrolytic cell was continuously energized at a constant voltage of 12V for 1.5 hours. After the reaction was completed, a sky-blue flocculent precipitate of MOF-199 was collected from the electrolytic cell. The obtained flocculent precipitate was washed and dried in a vacuum oven at 80℃ for 6 hours to obtain a blue precipitate of MOF-199. The dried MOF-199 material was evenly spread in a covered alumina corundum crucible and transferred to a quartz tube in a tube furnace. Air was purged using a stable N2 flow for 30 minutes, and then the furnace temperature was raised to 550℃, held for half an hour, and then further raised to 900℃. The temperature was maintained at 900℃ for 6 hours to achieve further carbonization, obtaining C@Cu nanoporous carbon material. Six μL of C@Cu suspension was drop-coated onto a clean glassy carbon electrode surface and allowed to dry at room temperature to form a film, thus obtaining C@Cu / GCE. 0.25 mmol of PdCl₂ was added to 20 mL of a 0.1 mol / L H₂SO₄ mixed solution and stirred thoroughly until homogeneous. The C@Cu / GCE was then immersed in the mixed solution, ensuring the solution completely covered the modified electrode surface, and soaked for 25 minutes before being removed. After standing and drying, the C@Cu-Pd modified glassy carbon electrode was obtained, denoted as Pd / C@Cu / GCE.

[0052] Performance testing

[0053] The surface morphology of the two groups of samples, Comparative Example 2 and Example 1, was observed using a scanning electron microscope. Figure 1 It can be seen that the electrode surface of Example 1 has a flower-like structure with a high specific surface area, while Figure 2 The electrode surface of Comparative Example 2, prepared without the addition of surfactant, did not exhibit a flower-like structure. Further investigation of the surface elemental distribution of Example 1 was conducted using energy dispersive spectroscopy (EDS). Figure 3 It can be seen that the high specific surface area flower-like structure in Example 1 is mostly composed of Pd and Cu elements. The formation of the Pd-Cu high specific surface area flower-like structure is beneficial to increasing the number of effective active sites exposed on the catalyst surface, thereby further improving the electrocatalytic ability of the catalyst.

[0054] Using the above-described electrode as the working electrode, a graphite rod as the auxiliary electrode, and mercury / mercury oxide as the reference electrode, a three-electrode system was constructed. The hydrogen evolution electrocatalytic activity of each electrode prepared above was tested in 1M KOH solution. The hydrogen evolution overpotentials of Comparative Examples 1 and 2 and Examples 1-3 are shown in Table 1. It can be seen that the hydrogen evolution overpotential of Comparative Example 1 without Pd particles is 401 mV, which is worse than that of the electrode with Pd particles. Comparative Example 2 without surfactant shows a significant difference in electrocatalytic activity compared to Examples 1-3 prepared with surfactant. The presence of the high specific surface area flower-like Pd-Cu structure increases the number of effective active sites exposed on the electrode surface of Examples 1-3, thereby enhancing the electrocatalytic activity and reducing the hydrogen evolution overpotential.

[0055] from Figure 5 As can be seen from the XRD patterns of Comparative Example 1 and Example 1, Comparative Example 1 exhibits a high-intensity diffraction peak on the Cu(111) plane at 2θ = 43.472°. In contrast, the XRD pattern of Example 1, in addition to retaining the diffraction peaks of Cu, also shows strong diffraction peaks on the Pd(111) plane and diffraction peaks of the Cu2O structure.

[0056] Table 1 shows the electrocatalytic hydrogen evolution activity evaluation of the catalysts obtained by the preparation methods of Comparative Examples 1 and 2 and Examples 1-3 (comparison of catalyst hydrogen evolution overpotential).

[0057] Table 1

[0058] Sample Name Comparative Example 1 Comparative Example 2 Example 1 Example 2 Example 3 hydrogen evolution overpotential 401mV 200mV 110mV 166mV 118mV

[0059] As shown in Table 1, the hydrogen evolution overpotential of the unloaded Pd-particle C@Cu / GCE (Comparative Example 1) is 401 mV, which is significantly lower than that of the Pd-particle-loaded electrode. The Pd / C@Cu / GCE (Comparative Example 2) without surfactant shows a significant difference in electrocatalytic activity compared to Examples 1-3 prepared with surfactant. The C@Cu-Pd / GCE prepared with a chemical reduction reaction time of 25 min exhibits the best electrocatalytic hydrogen evolution activity at 10 mA·cm⁻¹. -2 The hydrogen evolution overpotential at a current density of 110 mV (Example 1) is superior to that of the metal-organic framework-derived Cu-doped CeO2-supported PdCu alloy catalyst disclosed in CN 114164446 A in the electrochemical hydrogen evolution reaction at 10 mA·cm⁻¹. -2 The hydrogen evolution overpotential at the current density is 118 mV.

[0060] When the reaction time is 10 min, the high specific surface area Pd-Cu flowers do not grow completely, resulting in poor electrocatalytic hydrogen evolution performance at 10 mA·cm⁻¹. -2 The hydrogen evolution overpotential at the current density is 166mV (Example 2).

[0061] The above embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of protection of this application. Any non-substantial changes and substitutions made by those skilled in the art based on this application shall fall within the scope of protection claimed by this application.

Claims

1. A method for preparing a MOF material derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst, characterized in that: The preparation method includes A1, preparing MOF-derived C@Cu support: adding organic ligands and supporting electrolyte to an electrolyte, using an electrochemical method with copper sheets of equal area as the anode and cathode respectively, the copper ions obtained by electrolysis effectively bond with the organic ligands in the electrolyte to prepare MOF-199 material, and obtaining MOF-derived C@Cu support material after pyrolysis; A2, preparing C@Cu / GCE: dispersing C@Cu porous carbon nanomaterials in a mixed solution of Nafion ethanol solution, ethanol and deionized water to form a suspension, drop-coating the suspension onto a clean glassy carbon electrode surface, and then allowing it to stand and dry at room temperature to obtain C@Cu / GCE; A3. Activation of C@Cu / GCE: A three-electrode system was constructed using C@Cu / GCE as the working electrode, a platinum sheet as the counter electrode, and a saturated calomel electrode as the reference electrode. The C@Cu / GCE surface was activated using cyclic voltammetry in a 0.1 mol / L H2SO4 solution. The cyclic voltammetry was performed by scanning three times at a scan rate of 50 mV / s within a potential range of -0.4 to 0.8 V to activate the C@Cu / GCE surface. A4. Preparation of high specific surface area C@Cu-Pd / GCE: The activated C@Cu / GCE was immersed in a mixed solution of PdCl2, sodium dodecyl sulfonate, and H2SO4 for 25 min to prepare C@Cu-Pd / GCE with high specific surface area Pd-Cu flowers on the surface.

2. The preparation method of the C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst derived from the MOF material according to claim 1, characterized in that: The organic ligand is pyromellitic acid.

3. The preparation method of the C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst derived from the MOF material according to claim 1, characterized in that: The MOF-199 material was prepared by continuously applying a constant voltage of 12V for 1.5 hours.

4. The preparation method of the C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst derived from the MOF material according to claim 1, characterized in that: The pyrolysis in step A1 involves heating the organic linker to 500°C at a rate of 2°C / min under a N2 atmosphere for 30 minutes, followed by further carbonization at 900°C for 6 hours.

5. The method for preparing a C@Cu supported high specific surface Pd-Cu hydrogen evolution catalyst derived from a MOF material according to claim 1, characterized in that: The suspension C@Cu was prepared by mixing and dispersing 60 μL of 50% Nafion ethanol solution, 125 μL of ethanol, 375 μL of deionized water, and 40 mg of C@Cu powder.

6. The method for preparing a MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst according to claim 1, characterized in that: The volume of the C@Cu porous nanocarbon material suspension dropped onto the surface of the clean glassy carbon electrode is 6 μL.

7. The method for preparing a MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst according to claim 1, characterized in that: The method for preparing a C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst derived from MOF material according to claim 1 is characterized in that: the concentration of PdCl2 and sodium dodecyl sulfonate in 0.1 mol / L H2SO4 solution is 12.5 mmol / L.

8. A MOF material-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst obtained by the preparation method according to any one of claims 1 to 7, characterized in that: The MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst is composed of Cu and Cu2O support, Pd particles, and high specific surface area Pd-Cu flowers. In the C@Cu-Pd catalyst, C@Cu not only serves as a support to disperse Pd particles and prevent aggregation, but Cu in the support can also interact with Pd to form high specific surface area Pd-Cu flowers.

9. The MOF-derived C@Cu supported high specific surface area Pd-Cu hydrogen evolution catalyst according to claim 8, characterized in that: The MOF-derived C@Cu-Pd catalyst has an overpotential of 110 mV at a current density of 10 mA•cm -2 in the electrochemical hydrogen evolution reaction.

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