Ti net substrate loaded manganese ruthenium oxide composite electrode material and preparation method and application thereof

Abstract

The invention belongs to the technical field of electro-catalysis, and particularly relates to a Ti net substrate loaded manganese ruthenium oxide composite electrode material and a preparation method and application thereof.The preparation method mainly comprises the steps that a pretreated Ti net substrate is placed in an electrolyte containing manganese salt, acetate and sulfate, electro-deposition is conducted on the Ti net substrate, and the Ti net substrate loaded manganese ruthenium oxide composite electrode material is obtained; then putting into a muffle furnace for annealing to obtain Ti / MnOx; and then, soaking and drying in a ruthenium salt solution for multiple times, and annealing in a muffle furnace to obtain Ti / MnOx-RuOy. The preparation method has the advantages of simple and convenient process, mild reaction conditions and low cost, and the prepared composite electrode material has excellent acidic OER performance and stability when being used as a water electrolysis anode.

Description

Technical Field

[0001] This invention relates to the field of electrode materials technology, specifically to a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate, its preparation method, and its application. Background Technology

[0002] With the continued growth of global energy demand and the accelerated consumption of fossil fuels, energy security and environmental sustainability have become core challenges for human societal development. Against this backdrop, clean and renewable energy sources, represented by hydrogen energy, are considered key supports for future energy structure transformation due to their high energy density and zero carbon emissions. Water electrolysis for hydrogen production, as the core pathway for green hydrogen production, directly impacts the large-scale application of hydrogen energy in terms of efficiency and economics. The oxygen evolution reaction (OER), as the rate-controlling step in the overall water electrolysis reaction, is a crucial half-reaction that restricts overall performance.

[0003] Compared to alkaline media, acidic OER systems have become a research hotspot due to their advantages such as high current density and fast kinetics. However, OER reactions in this system face the dual challenges of strong acid corrosion and high overpotential, placing stringent requirements on electrode materials. Currently, Ir-based materials (such as IrO2) are considered the best catalysts for acidic OERs due to their excellent performance, but their low abundance in the Earth's crust and high material cost severely hinder their large-scale application in acidic water electrolysis. Ru-based materials, while exhibiting high intrinsic activity and relatively low cost, suffer from fatal flaws such as easy solubility in acidic environments and poor long-term stability under high current. Although current research attempts to improve the performance of Ru-based materials through metal cation doping, oxygen vacancy defect engineering, and the construction of heterogeneous composite structures, a common contradiction exists: "activity enhancement - difficulty in maintaining stability," and a synergistic optimization of both has not yet been achieved. Summary of the Invention

[0004] In view of this, and in view of the shortcomings of existing research, the purpose of this invention is to provide a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate, its preparation method and application. The preparation method has the advantages of simple and convenient process, mild reaction conditions and economical cost. The composite electrode material obtained has excellent acidic OER performance and stability when used as an anode for water electrolysis.

[0005] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows:

[0006] On one hand, the present invention provides a method for preparing a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate, comprising the following steps:

[0007] S1. Substrate pretreatment: A Ti mesh with a size of 2.5 cm × 2 cm was used as the electrodeposition substrate. The Ti mesh was placed in an oxalic acid solution for ultrasonic treatment, then washed and dried to obtain the pretreated Ti mesh.

[0008] S2. Preparation of electrodeposition solution: Add manganese salt, acetate, and sulfate to water, mix and obtain the electrodeposition solution;

[0009] S3, Manganese oxide electrodeposition: The pretreated Ti mesh was used as the working electrode with an area of ​​1 cm × 1 cm. A graphite rod was used as the counter electrode and a mercurous sulfate electrode was used as the reference electrode. The three-electrode electrodeposition system was constructed and electrodeposition was performed. Then the mesh was washed and dried.

[0010] S4. Manganese oxide annealing: The electrodeposited Ti mesh is placed in a muffle furnace for annealing to obtain Ti / MnO. x ;

[0011] S5, Ruthenium oxide support: Ti / MnO obtained after annealing x The sample was repeatedly soaked and dried in a ruthenium salt solution. After drying, the sample was annealed again in a muffle furnace to obtain Ti / MnO. x -RuO y ;

[0012] The three-electrode system used in this invention during the acidic oxygen evolution reaction is a Ti / MnO working electrode. x -RuO y (Working electrode area is 1 cm × 1 cm), counter electrode is graphite rod, reference electrode is mercurous sulfate electrode, and electrolyte is 0.5 MH2SO4.

[0013] Preferably, the concentration of the oxalic acid solution in step S1 is 0.03~0.08 g / mL; and the ultrasonic treatment time in the oxalic acid solution is 10~40 min.

[0014] Oxalic acid, as a weak organic acid, etches Ti fibers in the Ti mesh to a much lower degree than strong inorganic acids such as hydrochloric acid. This ensures appropriate etching of the Ti mesh, maintaining the integrity of the three-dimensional network structure, preventing framework collapse, and guaranteeing the stability of the electrode during long-term electrochemical operation. Ultrasonic treatment accelerates the etching of Ti fibers in the Ti mesh, removes the oxide film from the Ti mesh surface, and improves surface roughness and hydrophilicity without damaging the Ti fiber framework. Increased hydrophilicity increases the contact area between the Ti mesh and the electrolyte, optimizing the interfacial contact.

[0015] Preferably, the manganese salt in step S2 is manganese sulfate with a concentration of 0.1~0.3 M; the acetate is sodium acetate with a concentration of 0.1~0.6 M; and the sulfate is sodium sulfate with a concentration of 0.05~0.2 M.

[0016] Preferably, the electrodeposition method used in step S3 is cyclic voltammetry (CV), with 30 to 60 deposition cycles and a deposition rate of 0.01 to 2 V / s.

[0017] Preferably, in the muffle furnace annealing described in step S4, the annealing atmosphere is air, the heating rate is 3~8℃ / min, the annealing temperature is 200~250℃, and the annealing time is 4~8 h.

[0018] Preferably, the ruthenium salt solution in step S5 is a ruthenium trichloride solution with a concentration of 3~8 mg / mL.

[0019] Preferably, the soaking time is 5-8 minutes, and the drying operation is performed under an infrared lamp for 2-5 minutes, repeated 2-5 times. Multiple soaking and drying processes are to allow for better loading of ruthenium oxide.

[0020] Preferably, in step S5, a muffle furnace is used for annealing, the annealing atmosphere is air, the heating rate is 1~5℃ / min, the annealing temperature is 200~350℃, and the annealing time is 1~4 h.

[0021] On the other hand, the present invention provides a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate obtained according to the above preparation method.

[0022] Furthermore, this invention also provides an application of the Ti mesh substrate-loaded manganese ruthenium oxide composite electrode material obtained according to the preparation method described above in the acidic oxygen evolution process of hydrogen production by water electrolysis.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] (1) A method for preparing a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate according to the present invention, wherein a Ti mesh is used as the substrate material and an electrodeposition-annealing strategy is adopted to construct MnO. x -RuO y The active component was innovatively designed and constructed from three dimensions: structural support, stability enhancement, and activity enhancement. Through Ti network support, utilizing the chemical inertness and conductivity of Ti, MnO was stabilized. x -RuO y The active component, on the other hand, enhances charge separation efficiency, providing a "rigid framework" for the long-term stable operation of the anode in acidic environments. MnO x -RuO yThe active component can effectively reduce the use of the noble metal Ru through the participation of the Mn component, and can also improve the acid stability of the active component through the interaction between the two components, ultimately resulting in a better Ti / MnO product. x -RuO y It exhibits excellent acidic OER activity and stability. Furthermore, the Ti / MnO prepared on the substrate material in this invention... x -RuO y When conducting acidic water electrolysis tests, it can be used directly as the anode without any subsequent steps, making the operation simple.

[0025] (2) The preparation method of the present invention has significant advantages such as mild synthesis conditions, simple process and low cost, which have significant advantages for subsequent large-scale production.

[0026] (3) Ti / MnO prepared by this invention x -RuO y It exhibits excellent acidic OER activity at 10 mA cm⁻¹. -2 At current density, its overpotential is only 200 mV, which is lower than that of the control electrode materials.

[0027] (4) Ti / MnO prepared by the present invention x -RuO y It exhibits excellent acidic OER stability at 50 mA cm⁻¹. -2 It can operate stably for 120 hours under constant current density. Attached Figure Description

[0028] Figure 1 The Ti / MnO prepared in Example 1 of this invention x -RuO y SEM image of the composite electrode material.

[0029] Figure 2 The Ti / MnO prepared in Comparative Example 1 of this invention x SEM image.

[0030] Figure 3 The Ti / MnO prepared in Example 1 of this invention x -RuO y EDS elemental distribution diagram of composite electrode material.

[0031] Figure 4 The Ti / MnO prepared in Example 1 of this invention x -RuO y EDS scan of composite electrode material.

[0032] Figure 5This is the LSV diagram of the composite electrode material prepared in Examples 1-4 of the present invention.

[0033] Figure 6 These are LSV diagrams of the electrode materials prepared in Embodiment 1 and Comparative Examples 1-3 of the present invention.

[0034] Figure 7 The graph shows the stability chronopotential test results of Embodiment 1, Comparative Example 1, and Comparative Example 3 of the present invention. Detailed Implementation

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0036] In this invention, unless otherwise specified, all raw materials used are commercially available products in the art, and all operations are performed at room temperature.

[0037] Example 1

[0038] This embodiment provides a method for preparing composite electrode materials loaded on a Ti mesh substrate, the specific steps of which are as follows:

[0039] S1. Substrate pretreatment: Ti mesh was used as the electrodeposition substrate. The size of the Ti mesh was 2.5 cm × 2 cm. The Ti mesh was placed in 0.06 g / mL oxalic acid solution and ultrasonically treated for 20 min. Then it was washed 3 times and dried at 60℃ for 30 min to obtain the pretreated Ti mesh.

[0040] S2. Preparation of electrodeposition solution: Add 1.0142 g manganese sulfate, 0.9844 g sodium acetate, and 0.4262 g sodium sulfate to 30 mL of water, mix and stir to obtain the electrodeposition solution;

[0041] S3, Manganese oxide electrodeposition: A pretreated Ti mesh was used as the working electrode with an area of ​​1 cm × 1 cm. A graphite rod was used as the counter electrode and a mercurous sulfate electrode was used as the reference electrode. The three-electrode electrodeposition system was constructed by placing the electrodeposition system in the electrodeposition solution. Electrodeposition was performed by cyclic voltammetry with 40 deposition cycles and a deposition rate of 0.05 V / s. The electrodeposition was then washed and dried.

[0042] S4. Manganese oxide annealing: The electrodeposited Ti mesh was annealed in a muffle furnace under air atmosphere at a heating rate of 5℃ / min and an annealing temperature of 220℃ for 6 h to obtain Ti / MnO. x ;

[0043] S5, Ruthenium oxide support: Ti / MnO obtained after annealing x The sample was repeatedly immersed and dried three times in 5 mg / mL ruthenium trichloride solution. The immersion time was 5 min, and the drying time under an infrared lamp was 3 min. After drying, the sample was annealed again in a muffle furnace under an air atmosphere at a heating rate of 2 °C / min, an annealing temperature of 250 °C, and an annealing time of 2 h to obtain Ti / MnO. x -RuO y Composite electrode materials.

[0044] Example 2

[0045] The difference between this embodiment and Embodiment 1 is that the annealing temperature in step S5 is adjusted to 200℃, and the material is denoted as Ti / MnO. x -RuO y -200.

[0046] Example 3

[0047] The difference between this embodiment and Embodiment 1 is that the annealing temperature in step S5 is adjusted to 300℃, and the material is denoted as Ti / MnO. x -RuO y -300.

[0048] Example 4

[0049] The difference between this embodiment and Embodiment 1 is that the annealing temperature in step S5 is adjusted to 350℃, and the material is denoted as Ti / MnO. x -RuO y -350.

[0050] Comparative Example 1

[0051] A composite electrode material, the difference between this comparative example and Example 1 is that the S5 operation step is omitted, i.e., ruthenium oxide is not loaded, and the material is denoted as Ti / MnO. x .

[0052] Comparative Example 2

[0053] A composite electrode material, the difference between this comparative example and Example 1 is that, in operation step S5, after soaking and drying in ruthenium salt solution, no subsequent annealing step is performed. The material is denoted as Ti / MnO. x - RuO y -Pre.

[0054] Comparative Example 3

[0055] A composite electrode material, the difference between this comparative example and Example 1 is that it does not include the S2-S4 operation steps, i.e., it does not support manganese oxide. The material is denoted as Ti / RuO. y .

[0056] The inventors respectively tested the Ti / MnO obtained in the examples. x -RuO y The composite electrode material and the material obtained in the comparative example were characterized by scanning electron microscopy (SEM), and their structural morphology, elemental distribution, acidic oxygen evolution reaction (OER) electrocatalytic activity, and acidic OER electrocatalytic stability were tested. The results are as follows:

[0057] See Figure 1 and Figure 2 The Ti / MnO prepared in Example 1 x -RuO y Ti / MnO prepared in Comparative Example 1 x Morphological characterization was performed using scanning electron microscopy (SEM). By comparing the two images, it can be observed that the morphology of both composite electrode materials is a layer of sheet-like nanoarray material loaded on a Ti mesh substrate.

[0058] See Figure 3 and Figure 4 The Ti / MnO prepared in Example 1 x -RuO y Perform energy-dispersive spectroscopy (EDS) analysis from... Figure 3 and Figure 4 As can be seen, the three elements Mn, Ru, and O are uniformly distributed on the Ti grid substrate in the sample, indicating that MnO x -RuO y The composite active component was successfully loaded.

[0059] See Figure 5 The Ti / MnO prepared in Example 1 was used respectively. x -RuO y Ti / MnO prepared in Example 2 x -RuO y -200, Ti / MnO prepared in Example 3 x -RuO y -300, Ti / MnO prepared in Example 4 x -RuO y Using -350 as the working electrode, a graphite rod as the counter electrode, and a mercurous sulfate electrode as the reference electrode, LSV testing was conducted in a three-electrode system using 0.5 M H₂SO₄ as the electrolyte. As shown in the figures, the composite electrode materials prepared in Examples 1-4 all exhibit high acidic OER catalytic activity, low overpotential, and excellent oxygen evolution performance. Furthermore, the Ti / MnO₂ prepared in Example 1...x -RuO y Composite electrode materials exhibit higher catalytic activity, lower overpotential, and superior oxygen evolution performance in acidic OER.

[0060] See Figure 6 The Ti / MnO prepared in Example 1 was used respectively. x -RuO y Ti / MnO prepared in Comparative Example 1 x Ti / MnO prepared in Comparative Example 2 x -RuO y -Pre, Ti / RuO prepared in Comparative Example 3 y Using a graphite rod as the working electrode and a mercurous sulfate electrode as the reference electrode, LSV testing was performed in a three-electrode system using 0.5 M H₂SO₄ as the electrolyte. As can be seen from the figure, compared to Comparative Examples 1 to 3, the Ti / MnO₂ prepared in Example 1 of this invention… x -RuO y The composite electrode material exhibits higher catalytic activity in acidic OER at 10 mA cm⁻¹. -2 At current density, its overpotential is only 200 mV, which is lower than that of the control electrode materials.

[0061] See Figure 7 The Ti / MnO prepared in Example 1 was used respectively. x -RuO y Ti / MnO prepared in Comparative Example 1 x Ti / RuO prepared in Comparative Example 3 y A graphite rod was used as the working electrode, a mercurous sulfate electrode as the reference electrode, and 0.5 M H₂SO₄ was used as the electrolyte in the three-electrode system at 50 mA cm⁻¹. -2 Chronopotential testing was performed. As can be seen from the figure, Ti / MnO... x -RuO y Optimal stability at 50 mA cm -2 It can operate stably and sustainably for 120 hours.

[0062] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for preparing a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate, characterized in that, Includes the following steps: S1. Substrate pretreatment: Using Ti mesh as the electrodeposition substrate, the Ti mesh is placed in oxalic acid solution for ultrasonic treatment, then washed and dried to obtain the pretreated Ti mesh; S2. Preparation of electrodeposition solution: Add manganese salt, acetate, and sulfate to deionized water, mix and obtain the electrodeposition solution; S3. Electrodeposition of manganese oxides: A three-electrode electrodeposition system was constructed by using a pretreated Ti mesh as the working electrode, a graphite rod as the counter electrode, and a mercurous sulfate electrode as the reference electrode in the electrodeposition solution. Electrodeposition was then carried out, followed by washing and drying. S4. Manganese oxide annealing: The electrodeposited Ti mesh is placed in a muffle furnace for annealing to obtain Ti / MnO. x ; S5, Ruthenium oxide support: Ti / MnO obtained after annealing x The sample was repeatedly soaked and dried in a ruthenium salt solution. After drying, the sample was annealed again in a muffle furnace to obtain Ti / MnO. x -RuO y .

2. The method for preparing a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate as described in claim 1, characterized in that, The concentration of the oxalic acid solution in step S1 is 0.03~0.08 g / mL; the ultrasonic treatment time in the oxalic acid solution is 10~40 min.

3. The method for preparing a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate as described in claim 1, characterized in that, In step S2, the manganese salt is manganese sulfate with a concentration of 0.1~0.3 M; the acetate is sodium acetate with a concentration of 0.1~0.6 M; and the sulfate is sodium sulfate with a concentration of 0.05~0.2 M.

4. The method for preparing a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate as described in claim 1, characterized in that, The electrodeposition method used in step S3 is cyclic voltammetry (CV), with 30 to 60 deposition cycles and a deposition rate of 0.01 to 2 V / s.

5. The method for preparing a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate as described in claim 1, characterized in that, In the muffle furnace annealing described in step S4, the annealing atmosphere is air, the heating rate is 3~8℃ / min, the annealing temperature is 200~250℃, and the annealing time is 4~8 h.

6. The method for preparing a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate as described in claim 1, characterized in that, In step S5, the ruthenium salt solution is a ruthenium trichloride solution with a concentration of 3~8 mg / mL.

7. The method for preparing a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate as described in claim 1, characterized in that, The soaking time in step S5 is 5-8 min, the drying is carried out under an infrared lamp for 2-5 min, and the drying is repeated 2-5 times; the annealing atmosphere is air, the heating rate is 1-5℃ / min, the annealing temperature is 200-350℃, and the annealing time is 1-4 h.

8. A composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate obtained by the preparation method according to any one of claims 1 to 7.

9. The application of a composite electrode material of manganese ruthenium oxide loaded on a Ti mesh substrate obtained by the preparation method according to any one of claims 1 to 7 in the acidic oxygen evolution process of hydrogen production by water electrolysis.

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