Molybdenum carbide nano flower ball-loaded low-platinum-loading-capacity hydroxide catalyst and preparation method thereof

Abstract

The invention discloses a molybdenum carbide nano flower ball-loaded low-platinum-loading-capacity hydroxide catalyst and a preparation method thereof, and belongs to the technical field of new energy materials. The invention designs and synthesizes a molybdenum carbide carrier with a porous nanoflower structure for providing anchoring positioning for a platinum-nickel electric load. The invention finds that the alkaline HOR performance of the Pt / Ni-coated Mo2C catalyst is the best when the content ratio of platinum to nickel is 10: 1. Structural characterization and electrochemical hydrogen oxidation performance tests of the system show that the Pt / Ni-coated Mo2C catalyst can reach the current density of 2mA cm <-2 > under the overpotential of 50mV, and the performance of the Pt / Ni-coated Mo2C catalyst is equivalent to that of a commercial platinum-carbon (20wt.% Pt / C) catalyst. The invention provides a new thought for developing an efficient and stable hydroxide catalyst with low platinum (0.3364 wt.%) loading capacity. The supported electrocatalyst has very strong electrocatalytic hydrogen oxidation performance and very good electrocatalytic application potential.

Description

Technical Field

[0001] This invention belongs to the field of new materials technology, specifically relating to a low-platinum-loaded hydroxide catalyst supported on molybdenum carbide nanoflowers and its preparation method. Background Art

[0003] Fuel cells can efficiently convert hydrogen energy into electrical energy, which is of great significance for promoting the development of hydrogen energy. Proton exchange membrane fuel cells (PEMFCs) are one of the most advanced fuel cell technologies currently available. In acidic electrolyte environments, the catalyst for the oxygen reduction reaction (ORR) at the cathode of PEMFCs is highly dependent on platinum group metals, which significantly limits their large-scale application. With the continuous advancement of anion exchange membrane technology, alkaline electrolyte fuel cells (AEMFCs) are gradually attracting increasing attention. The ORR in alkaline electrolytes can use non-precious metals as catalysts, achieving performance comparable to platinum group metals (PGMs), making AEMFCs a promising alternative to PEMFCs. However, even with platinum group metal (PGM) catalysts, the kinetic rate of the hydrogen oxidation reaction (HOR) in alkaline media is 2-3 orders of magnitude slower than that in acidic media. This means that HOR under alkaline conditions requires a higher PGM loading to achieve the same performance as in acidic electrolytes.

[0004] Developing alkaline HOR catalysts with low noble metal content is of great significance for promoting the development of anion exchange membrane fuel cells. Constructing atomically scaled platinum group metal supported electrocatalysts is a common strategy for developing cost-effective alkaline HOR electrocatalysts. Transition metal carbides (TMCs) are widely considered one of the most promising supports for supported electrocatalysts due to their tunable structure, platinum-like electronic structure, and excellent stability. However, metal-supported alkaline HOR catalysts based on TMCs are still in their early stages. A key scientific question is how to achieve precise control of the electronic interactions between atomically scaled noble metals and carbide substrates to achieve more efficient electrocatalytic activity. With the development of hydrogen energy technology, achieving efficient HOR under alkaline conditions has become a research hotspot. Molybdenum carbide (Mo2C) has become an ideal catalyst support due to its superior conductivity and catalytic performance. However, further improving its performance and stability remains an important research direction. Summary of the Invention

[0005] The purpose of this invention is to provide a low-platinum-loading hydrogenation catalyst supported on molybdenum carbide nanoflowers and its preparation method. This method designs and synthesizes a molybdenum carbide support with a porous nanoflower structure to improve the alkaline hydrogenation reactivity (HOR) performance of a platinum-nickel electrocatalyst. This invention investigates the effect of platinum-nickel content on alkaline HOR performance, finding that the Pt / Ni@Mo2C catalyst exhibits the best alkaline HOR performance when the platinum-nickel ratio is 10:1. Systematic structural characterization and electrochemical hydrogenation performance tests show that the Pt / Ni@Mo2C catalyst can achieve a 2 mA cm⁻¹ overpotential at 50 mV. -2 The current density is comparable to that of commercial platinum-carbon (Pt / C) catalysts. This work provides a new approach for developing highly efficient and stable hydroxide catalysts with low platinum (0.3364%) loadings. To achieve the above objectives, the present invention provides the following scheme:

[0006] One of the technical solutions of the present invention is to provide a low platinum loading hydroxide catalyst supported on molybdenum carbide nanoflowers. The supported electrocatalyst includes a conductive support with a high specific surface area and a reduced-modified metal nanomaterial supported on the conductive support.

[0007] Furthermore, the conductive carrier is molybdenum carbide;

[0008] Furthermore, the molybdenum carbide support used in this invention has a high specific surface area;

[0009] Furthermore, the morphology of the molybdenum carbide conductive carrier is a nano-flower-like structure;

[0010] Furthermore, the metal nanomaterial is Pt or Ni.

[0011] The second technical solution of this invention: provides a low-platinum-loading hydroxide catalyst supported on molybdenum carbide nanospheres and its preparation method, comprising the following steps:

[0012] We designed and synthesized alkaline electrocatalysts for hydrogenation supported on molybdenum carbide and platinum acetylacetone and nickel acetylacetone. After metal loading, we obtained molybdenum carbide electrocatalysts with different metal atomic-level doping. Then, we systematically studied the structure-activity relationship between the structure composition of the catalyst and its electrocatalytic hydrogenation performance.

[0013] The synthesis of the catalyst (Pt / Ni@Mo2C) includes the following steps:

[0014] The synthesized Mo7-PDA was placed in a tube furnace and kept at 450℃ for 2 hours and 800℃ for 3 hours under an Ar atmosphere to obtain Mo2C nanoflower carrier with high specific surface area.

[0015] A metal material solution is added to the carrier solution and stirred to obtain a mixed solution. After filtration and drying, a molybdenum carbide carrier-loaded metal material is obtained.

[0016] The metal material supported on the molybdenum carbide support was reduced at 400°C for 2 hours in an H2 / Ar atmosphere to obtain a supported catalyst.

[0017] The concentration of the molybdenum carbide carrier solution was 3.33 mg / ml;

[0018] The concentration of the metal nanomaterial solution is 0.46-0.69 mg / ml.

[0019] Furthermore, the mass ratio of the loaded metal nanoparticles (platinum to nickel) is 10:1;

[0020] Furthermore, the metal nanomaterials include platinum acetylacetonate and / or nickel acetylacetonate;

[0021] Furthermore, the drying process is vacuum drying.

[0022] Addressing the issues of easy aggregation, poor binding force, and poor hydrophilicity inherent in metal nanoparticles, this invention utilizes a high specific surface area carrier to inhibit aggregation, stabilize dispersion, and increase the active specific surface area of ​​metal nanoparticles. Simultaneously, during the formation of molybdenum carbide-supported metal nanoparticles, the metal nanoparticles provide active sites. The high specific surface area of ​​the molybdenum carbide nanospheres provides anchoring points for the loading of metal nanoparticles, allowing for the control of nanoparticle size and the acquisition of different quantum effects, thus achieving stable high-metal-quality activity. Furthermore, the molybdenum carbide carrier enables the formation of a highly negatively charged shell on the surface of the metal particles, significantly inhibiting aggregation under storage, catalytic, and harsh conditions.

[0023] The third technical solution of the present invention provides an application of the above-mentioned metal nanoparticles anchored on molybdenum carbide nanoflowers as an electrode modification material in the preparation of electrocatalytic reaction electrodes.

[0024] Furthermore, the electrocatalytic reaction includes electrocatalytic hydrogenation.

[0025] The fourth technical solution of the present invention provides an electrode for electrocatalytic hydrogenation, wherein the active component of the electrode includes a supported catalyst anchored on molybdenum carbide nanospheres as described above.

[0026] Fifth technical solution of the present invention: a method for electrocatalytic hydrogenation, wherein the above-mentioned electrode is used as the working electrode.

[0027] The present invention discloses the following technical effects:

[0028] The supported catalyst prepared by this invention, with metal nanoparticles anchored on molybdenum carbide nanoflowers, exhibits strong electrocatalytic hydrogenation performance and excellent potential for electrocatalytic applications.

[0029] This invention provides a novel strategy for synthesizing high-performance hydrogenation catalysts, with the following key advantages: ① It proposes a strategy for controllably introducing Pt and Ni doping onto the surface of Mo₂C; ② Mo₂C is a nano-flower-like structure with a high specific surface area, providing active sites for metal loading; ③ By introducing nickel, the platinum content is reduced, resulting in a catalyst with a final platinum content of only 0.3364%; ④ This synthesis method is simple, efficient, and controllable, enabling large-scale synthesis and providing significant potential for practical production. In summary, this method offers a new approach for synthesizing dispersed, atomically doped Mo-based catalysts. Systematic structural characterization and electrochemical hydrogenation performance testing show that the Pt / Ni@Mo₂C catalyst can achieve an overpotential of 2 mA cm⁻¹ at 50 mV. -2 The current density is comparable to that of commercial platinum-carbon (20 wt.% Pt / C) catalysts, which is of guiding significance for the preparation and industrialization of high-performance high-current electrocatalytic hydrogenation materials. Attached Figure Description

[0030] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0031] Figure 1 These are transmission electron microscope (TEM) images obtained using a metal load on Mo2C (Pt / Ni@Mo2C) according to an embodiment of the present invention;

[0032] Figure 2 These are scanning electron microscope (SEM) images obtained using Pt / Ni@Mo2C according to embodiments of the present invention;

[0033] Figure 3 These are high-resolution transmission electron microscope (HRTEM) images obtained using Pt / Ni@Mo2C according to embodiments of the present invention.

[0034] Figure 4 These are transmission electron microscope (TEM) images obtained according to the present invention using metal loading on Mo2C (Pt@Mo2C);

[0035] Figure 5 These are scanning electron microscope (SEM) images obtained using Pt@Mo2C as a comparative example according to the present invention;

[0036] Figure 6 These are high-resolution transmission electron microscope (HRTEM) images obtained using Pt@Mo2C as a comparative example according to the present invention.

[0037] Figure 7 These are Raman spectra obtained using Pt@Mo2C and Pt / Ni@Mo2C according to embodiments and comparative examples of the present invention;

[0038] Figure 8 These are XRD patterns and JCPDS standard patterns obtained using Pt@Mo2C and Pt / Ni@Mo2C according to embodiments and comparative examples of the present invention.

[0039] Figure 9 This is a comparative performance diagram of electrocatalytic hydrogenation obtained using Pt@Mo2C and Pt / Ni@Mo2C according to the present invention;

[0040] Figure 10 This is a comparison chart of the mass activity obtained by using Pt / Ni@Mo2C and Pt / Ni@Mo2C in this invention. Detailed Implementation

[0041] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0042] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0043] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0044] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the description of the invention. The description and examples are intended to be illustrative only.

[0045] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0046] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0047] In the specific embodiments of the present invention, the room temperature and ambient temperature are both 20-30℃.

[0048] The raw materials and reagents used in the specific embodiments of this invention are all commercially available products.

[0049] It should be noted that the carriers used in the specific embodiments of the present invention can be commercially available or self-made, without affecting the realization of the technical effect.

[0050] Example

[0051] (1) Synthesis of Mo7-PDA: Weigh 0.27g of ammonium heptamolybdate tetrahydrate ((NH4)6Mo7O 24 Dissolve 0.27 g of dopamine hydrochloride (C8H4H2O, Mo7) in 72 mL of deionized water. 12 Dissolve ClNO2 (PDA) in 144 mL of anhydrous ethanol and stir until dissolved. After both reactants are completely dissolved, add dopamine hydrochloride to ammonium heptamolybdate tetrahydrate and stir for 10 min. Add 1.10 mL of ammonia water to adjust the pH. Stir for 6 h, centrifuge directly (8500 rpm, 5 min), and wash three times with anhydrous ethanol. Place in a forced-air drying oven and dry overnight at 80 °C to obtain Mo7-PDA.

[0052] (2) Preparation of Mo2C substrate: The Mo7-PDA obtained in (1) was placed in a tube furnace and kept at 450℃ for 2h and 800℃ for 3h to obtain a porous nanoflower ball Mo2C substrate.

[0053] (3) Adsorption of Pt / Ni: 50 mg of Mo2C nanospheres were weighed as a substrate and ultrasonically dispersed in 15 ml of anhydrous ethanol. Then, 10.4 mg of platinum acetylacetonate and 2.304 mg of nickel acetylacetonate were weighed and ultrasonically dissolved in 15 ml and 5 ml of anhydrous ethanol, respectively. The completely dissolved platinum acetylacetonate and nickel acetylacetonate were added to the Mo2C substrate sequentially and stirred for 10 min. The mixture was then filtered, and the sample was placed in a vacuum drying oven and dried at 60 °C for 4 h.

[0054] (4) Preparation of Pt / Ni@Mo2C catalyst: The product obtained in the previous step was placed in a tube furnace and kept at 400℃ for 2 hours under H2 / Ar atmosphere to reduce the catalyst. Pt / Ni@Mo2C catalyst was obtained.

[0055] (5) Preparation of the electrocatalytic hydroxide negative electrode: Weigh 5 mg of Pt / Ni@Mo2C catalyst and grind it evenly in an agate mortar. Add a mixed dispersant of ethanol and Nafion solution, and sonicate to form a uniform dispersion. Then, heat the dispersion at 0.1963 cm⁻¹. 2 15 μL of the above solution was uniformly drop-coated onto a glassy carbon electrode and dried to form an electrode sheet.

[0056] (6) To characterize the electrocatalytic hydrogen evolution performance of the prepared electrode material, a three-electrode system was constructed using a DSR-M testing device from China National Chemical Engineering Co., Ltd. and a CHI760E electrochemical workstation from Shanghai Chenhua Co., Ltd. The hydrogen oxidation (HOR) performance of Pt / Ni@Mo2C was tested at room temperature. All electrochemical tests were conducted in a three-electrode system using a mercury / mercury oxide electrode as the reference electrode, a platinum wire as the counter electrode, the electrode prepared in step (5) as the working electrode, and 0.1 mol / L KOH solution as the electrolyte.

[0057] in, Figure 1 The transmission electron microscope (SEM) images obtained using the Mo2C-supported platinum acetylacetone catalyst (Pt / Ni@Mo2C) in the examples show that the Mo2C-supported platinum metal particles are few, uniformly distributed, and do not agglomerate.

[0058] in, Figure 2The scanning electron microscope (SEM) images obtained using Pt / Ni@Mo2C in the examples show that the synthesized catalysts retain the original morphology of the Mo2C substrate. All catalysts have good nanoflower-like structures. This nanoflower-like structure with high specific surface area is conducive to exposing more catalytic sites, thereby improving intrinsic catalytic activity.

[0059] in, Figure 3 In the example, the lattice spacing was measured using a high-resolution transmission electron microscope (HRTEM) obtained from Pt@Mo2C. The measured lattice spacing was 2.29 nm, corresponding to the (101) crystal plane of Mo2C.

[0060] Comparative Example 1

[0061] (1) Synthesis of Mo7-PDA: Weigh 0.27g of ammonium heptamolybdate tetrahydrate ((NH4)6Mo7O 24 Dissolve 0.27 g of dopamine hydrochloride (C8H4H2O, Mo7) in 72 mL of deionized water. 12 Dissolve ClNO2 (PDA) in 144 mL of anhydrous ethanol and stir until dissolved. After both reactants are completely dissolved, add dopamine hydrochloride to ammonium heptamolybdate tetrahydrate and stir for 10 min. Add 1.10 mL of ammonia water to adjust the pH. Stir for 6 h, centrifuge directly (8500 rpm, 5 min), and wash three times with anhydrous ethanol. Place in a forced-air drying oven and dry overnight at 80 °C to obtain Mo7-PDA.

[0062] (2) Preparation of Mo2C substrate: The Mo7-PDA obtained in (1) was placed in a tube furnace and kept at 450℃ for 2h and 800℃ for 3h to obtain a porous nanoflower ball Mo2C substrate.

[0063] (3) Ni adsorption: 50 mg of Mo2C nanospheres were weighed as a substrate and ultrasonically dispersed in 15 ml of anhydrous ethanol. Then, 230.5 mg of nickel acetylacetonate was weighed and ultrasonically dissolved in 15 ml of anhydrous ethanol. The completely dissolved nickel acetylacetonate was added to the Mo2C substrate and stirred for 10 min. The sample was filtered and placed in a vacuum drying oven at 60 °C for 4 h.

[0064] (4) Preparation of Ni@Mo2C catalyst: The product obtained in the previous step was placed in a tube furnace and kept at 400℃ for 2 hours under H2 / Ar atmosphere to reduce the catalyst. Ni@Mo2C catalyst was obtained.

[0065] (5) Preparation of the electrocatalytic hydrogenation negative electrode: Weigh 5 mg of Ni@Mo2C catalyst and grind it evenly in an agate mortar. Add a mixed dispersant of ethanol and Nafion solution, and sonicate to form a uniform dispersion. Then, heat the dispersion at 0.1963 cm⁻¹. 2 15 μL of the above solution was uniformly drop-coated onto a glassy carbon electrode and dried to form an electrode sheet.

[0066] (6) To characterize the electrocatalytic hydrogen evolution performance of the prepared electrode material, a three-electrode system was constructed using a DSR-M testing device from China National Chemical Engineering Co., Ltd. and a CHI760E electrochemical workstation from Shanghai Chenhua Co., Ltd. to test the hydrogen oxidation (HOR) performance of Ni@Mo2C at room temperature. All electrochemical tests were conducted in a three-electrode system with a mercury / mercury oxide electrode as the reference electrode, a platinum wire as the counter electrode, the electrode prepared in step (5) as the working electrode, and 0.1 mol / L KOH solution as the electrolyte solution.

[0067] Comparative Example 2

[0068] (1) Synthesis of Mo7-PDA: Weigh 0.27g of ammonium heptamolybdate tetrahydrate ((NH4)6Mo7O 24 Dissolve 0.27 g of dopamine hydrochloride (C8H4H2O, Mo7) in 72 mL of deionized water. 12 Dissolve ClNO2 (PDA) in 144 mL of anhydrous ethanol and stir until dissolved. After both reactants are completely dissolved, add dopamine hydrochloride to ammonium heptamolybdate tetrahydrate and stir for 10 min. Add 1.10 mL of ammonia water to adjust the pH. Stir for 6 h, centrifuge directly (8500 rpm, 5 min), and wash three times with anhydrous ethanol. Place in a forced-air drying oven and dry overnight at 80 °C to obtain Mo7-PDA.

[0069] (2) Preparation of Mo2C substrate: The Mo7-PDA obtained in (1) was placed in a tube furnace and kept at 450℃ for 2h and 800℃ for 3h to obtain a porous nanoflower ball Mo2C substrate.

[0070] (3) Adsorption of Pt: 50 mg of Mo2C nanospheres were weighed as a substrate and ultrasonically dispersed in 15 ml of anhydrous ethanol. Then, 10.4 mg of platinum acetylacetonate was weighed and ultrasonically dissolved in 15 ml of anhydrous ethanol. The completely dissolved platinum acetylacetonate was added to the Mo2C substrate and stirred for 10 min. The sample was filtered and placed in a vacuum drying oven at 60 °C for 4 h.

[0071] (4) Preparation of Pt@Mo2C catalyst: The product obtained in the previous step was placed in a tube furnace and kept at 400℃ for 2 hours under H2 / Ar atmosphere to reduce the catalyst. Pt@Mo2C catalyst was obtained.

[0072] (5) Preparation of the electrocatalytic hydrogenation negative electrode: Weigh 5 mg of Pt@Mo2C catalyst and grind it evenly in an agate mortar. Add a mixed dispersant of ethanol and Nafion solution, and sonicate to form a uniform dispersion. Then, heat the dispersion at 0.1963 cm⁻¹. 2 15 μL of the above solution was uniformly drop-coated onto a glassy carbon electrode and dried to form an electrode sheet.

[0073] (6) To characterize the electrocatalytic hydrogen evolution performance of the prepared electrode material, a three-electrode system was constructed using a DSR-M testing device from China National Chemical Engineering Co., Ltd. and a CHI760E electrochemical workstation from Shanghai Chenhua Co., Ltd. The hydrogen oxidation (HOR) performance of Pt@Mo2C was tested at room temperature. All electrochemical tests were conducted in a three-electrode system using a mercury / mercury oxide electrode as the reference electrode, a platinum wire as the counter electrode, the electrode prepared in step (5) as the working electrode, and 0.1 mol / L KOH solution as the electrolyte.

[0074] in, Figure 4 The transmission electron microscope (SEM) images obtained using the Mo2C-supported platinum acetylacetone catalyst (Pt@Mo2C) in the comparative example show that the Mo2C-supported platinum metal particles are few, uniformly distributed, and do not agglomerate.

[0075] in, Figure 5 The scanning electron microscope (SEM) images obtained using Pt@Mo2C in the comparative examples show that the synthesized catalysts retain the original morphology of the Mo2C substrate. All catalysts have good nanoflower-like structures. This nanoflower-like structure with high specific surface area is conducive to exposing more catalytic sites, thereby improving intrinsic catalytic activity.

[0076] in, Figure 6 In the comparative example, the lattice spacing was measured using a high-resolution transmission electron microscope (HRTEM) obtained from Pt@Mo2C. The measured lattice spacing was 2.29 nm, corresponding to the (101) crystal plane of Mo2C.

[0077] in, Figure 7 Raman spectra obtained using Pt@Mo2C and Pt / Ni@Mo2C according to embodiments and comparative examples of the present invention, 1365 cm⁻¹ -1 Defect carbon reflecting the catalyst structure, 1598 cm -1 Corresponding sp 2 In-plane stretching vibration of hybrid carbon, 560 cm -1 Corresponding to the stretching vibration of the Mo-C bond, 1100 cm -1Corresponding to the stretching vibration of the CO bond, no obvious characteristic Raman peaks of Pt and Ni were observed. The absence of obvious characteristic peaks of Pt and Ni nanoparticles in the Raman spectrum fully demonstrates that Pt and Ni nanoparticles did not aggregate on the molybdenum carbide nanoflowers.

[0078] in, Figure 8 According to the XRD and JCPDS standard spectra obtained by Pt@Mo2C and Pt / Ni@Mo2C in the embodiments and comparative examples of the present invention, obvious characteristic diffraction peaks of Mo2C (PDF card #35-0787) were observed in both samples at 34.4°, 38.0°, 39.4°, 52.1°, 61.5°, 69.6°, 72.4° and 74.6°, respectively. These peaks correspond to the (100), (002), (101), (102), (110), (103), (200) and (112) crystal planes of Mo2C, respectively, indicating the presence of the Mo2C phase in the material and proving the successful synthesis of the hexagonal Mo2C phase. No obvious Pt or Ni XRD peaks were found in the XRD images, indicating that the Pt and Ni nanoparticles did not agglomerate.

[0079] Test case

[0080] Weigh 5 mg of catalyst powder and add it to 475 μL of deionized water, 475 μL of isopropanol, and 50 μL of Nafion membrane solution. Sonicate to form a uniform dispersion. Then, take 15 μL of the dispersion and coat it onto a glassy carbon electrode with a loading of 0.38 mg cm⁻¹. -2 After drying, the working electrode is obtained.

[0081] The electrocatalytic hydrogen evolution performance of the above working electrode was characterized by the following tests:

[0082] The hydrogen oxidative stress (HOR) performance of Pt / Ni@Mo2C, Pt@Mo2C, and 20wt.% Pt / C was tested at room temperature using a three-electrode system built with a DSR-M testing equipment from China Physicochemical Corporation and a CHI760E electrochemical workstation from Shanghai Chenhua. The electrochemical tests were conducted in a three-electrode system with a reversible hydrogen electrode as the reference electrode, a platinum wire as the counter electrode, the above-prepared electrode as the working electrode, and 0.1 mol / L KOH solution as the electrolyte solution.

[0083] in, Figure 9 According to the comparative performance diagram of electrocatalytic hydrogenation obtained using Pt@Mo2C, Ni@Mo2C and Pt / Ni@Mo2C, electrochemical hydrogenation tests were performed in 0.1M KOH solution at a potential range of -0.05 to 0.5V (vs RHE) with a speed of 0.001mV·s. -1 The scan rate test linear sweep voltammetry (LSV) curve was obtained. Figure 3-8 It can be seen that at 2500 rpm, the HOR of Pt / Ni@Mo2C and Pt@Mo2C catalysts is close to that of commercial 20 wt.% PtC. At 50 mV, its current density is 1.98 mA / cm². -2 .

[0084] in, Figure 10 According to the comparison chart of mass activities obtained by Pt / Ni@Mo2C and Pt / Ni@Mo2C according to the present invention, the mass activity of Pt / Ni@Mo2C catalyst reaches 275 mA mg at a voltage of 50 mV. -1 The mass activity of the Pt@Mo2C catalyst is 182 mA mg. -1 All were higher than 8mA mg -1 The PtC catalyst, and the catalyst quality activity is significantly improved after doping with nickel nanoparticles.

[0085] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0086] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A low-platinum-loading hydroxide catalyst supported on molybdenum carbide nanospheres, characterized in that, The supported electrocatalyst includes a conductive support with a high specific surface area and metal nanoparticles supported on the conductive support.

2. The supported electrocatalyst as described in claim 1, characterized in that, The conductive carrier is a molybdenum carbide nanosphere; and / or, the metal nanomaterial includes Pt, non-Pt metals, alloys, or non-metallic compounds of metals; and / or, the morphology of the metal nanomaterial is a nanosphere.

3. A method for preparing a supported electrocatalyst as described in claim 1 or 2, characterized in that: We designed and synthesized alkaline electrocatalysts for hydrogenation supported on molybdenum carbide and platinum acetylacetone and nickel acetylacetone. After metal loading, we obtained molybdenum carbide electrocatalysts with different metal atomic-level doping. Then, we systematically studied the structure-activity relationship between the structure composition of the catalyst and its electrocatalytic hydrogenation performance. The synthesis of the catalyst (Pt / Ni@Mo2C) includes the following steps: The synthesized Mo7-PDA was placed in a tube furnace and kept at 450℃ for 2 hours and 800℃ for 3 hours under an Ar atmosphere to obtain Mo2C nanoflower carrier with high specific surface area. A metal material solution is added to the carrier solution and stirred to obtain a mixed solution. After filtration and drying, a molybdenum carbide carrier-loaded metal material is obtained. The metal material supported on the molybdenum carbide support was reduced at 400°C for 2 hours in an H2 / Ar atmosphere to obtain a supported catalyst. The concentration of the molybdenum carbide carrier solution was 3.33 mg / ml; The concentration of the metal nanomaterial solution is 0.46-0.69 mg / ml.

4. The preparation method according to claim 3, characterized in that, The metal nanoparticles have a platinum-nickel mass ratio of 10:

1.

5. The method for preparing the molybdenum carbide-supported platinum-nickel electrocatalyst as described in claim 3, characterized in that: The content of the precious metal platinum is 0.3364 wt.%.

6. The application of a low-platinum-loaded hydroxide catalyst supported on molybdenum carbide nanoflowers as described in claim 1 or 2 as an electrode modification material in the preparation of electrocatalytic reaction electrodes.

7. An electrode for electrocatalytic hydrogenation, characterized in that, The active component of the electrode includes the supported catalyst described in claim 1 or 2, in which metal nanoparticles are anchored on molybdenum carbide nanoflowers.

8. A method for electrocatalytic hydrogenation, characterized in that, The method uses the electrode described in claim 7 as the working electrode.

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