Catalytic electrode for PEM water electrolysis hydrogen production and preparation method

Abstract

According to the catalytic electrode for PEM water electrolysis hydrogen production and the preparation method, the manganese-based oxide serves as a basic active component and is matched with rhenium element doping to form a non-noble metal catalytic system, and dependence on rare noble metal such as iridium and ruthenium is thoroughly eliminated. The raw materials of manganese and rhenium are wide in source and low in cost, and the stability of the framework structure of manganese oxide is fundamentally enhanced by precisely doping the rhenium element and utilizing the chemical inertness and corrosion resistance of rhenium. Due to introduction of rhenium, conversion of manganese to high-valence soluble ions in an acidic high-potential environment is effectively inhibited, and collapse of a catalyst structure and loss of active components are avoided. Experimental data show that the accelerated service life of the rhenium-manganese composite gold-based composite metal oxide catalytic electrode provided by the invention reaches up to 80 hours in a 0.5 M H2SO4 strong acid electrolyte under the current density of 1A. Cm <-2 >, the stability requirement of long-period operation of a PEM electrolytic bath is completely met, and the core short plate of a traditional manganese-based non-noble metal catalyst is solved.

Description

Technical Field

[0001] This invention relates to the field of PEM water electrolysis hydrogen production technology, and particularly to a catalytic electrode for PEM water electrolysis hydrogen production and its preparation method. Background Technology

[0002] Proton exchange membrane (PEM) water electrolysis hydrogen production technology has irreplaceable strategic value in new energy storage and the construction of the hydrogen energy industry chain due to its ability to efficiently produce high-purity green hydrogen. However, the oxygen evolution reaction (OER) of this technology faces an extremely harsh working environment. The combined effects of a strongly acidic electrolyte and a high oxidation potential require the anode catalyst to possess both excellent catalytic activity and structural stability. This makes the current industry heavily reliant on scarce precious metals such as iridium and ruthenium and their oxides as core catalyst components.

[0003] The limited reserves of precious metal catalysts and the high costs of mining and purification directly increase the overall cost of PEM water electrolysis for hydrogen production, becoming a core bottleneck restricting the large-scale promotion and application of this technology.

[0004] Therefore, developing non-precious metal anode catalysts that combine high catalytic activity, long-term stability, and low cost is a key breakthrough for promoting the industrialization of PEM water electrolysis hydrogen production technology. Summary of the Invention

[0005] To address the problems existing in the background art, the present invention provides a catalytic electrode for PEM water electrolysis hydrogen production and its preparation method.

[0006] The specific details of the invention are as follows: In a first aspect, the present invention provides a method for preparing a catalytic electrode for PEM water electrolysis hydrogen production, the method comprising: A homogeneous active layer coating solution is obtained by mixing a soluble manganese salt solution and a soluble rhenium salt solution, and then applying a combination of ultrasonic and mechanical stirring to the resulting mixture. After coating the homogeneous active layer coating liquid onto the surface of the conductive substrate, a programmed temperature rise heat treatment is performed under an oxidizing atmosphere to cause the homogeneous active layer coating liquid coated on the surface of the conductive substrate to undergo thermal decomposition at 250 ℃-600 ℃, forming a crystalline rhenium-manganese composite gold oxide catalytic active layer.

[0007] Optionally, the concentration of total metal ions in the homogeneous active layer coating solution is 0.01 mol / L-5.0 mol / L.

[0008] Optionally, in the homogeneous active layer coating solution, the molar ratio of rhenium ions to manganese ions is 0.01-2.

[0009] Optionally, the coating method is brushing, spraying, spin coating, or dip-coating.

[0010] Optionally, the thermal decomposition is carried out in an oxidizing atmosphere, and the programmed temperature heat treatment includes: heating to 100 ℃-150 ℃ at a heating rate of 1 ℃ / min to 20 ℃ / min, holding at that temperature for 10 min to 30 min, and then continuing to heat to 250 ℃-600 ℃ at a heating rate of 1 ℃ / min to 20 ℃ / min, holding at that temperature for 1 h to 8 h.

[0011] Optionally, the conductive substrate is selected from porous titanium or titanium alloy sintered plates, titanium fiber felt, carbon paper, carbon cloth, or glass / ceramic substrates with a conductive oxide film on the surface.

[0012] Optionally, the duration of the ultrasonic and mechanical stirring interaction is 30 min to 120 min; Continuous stirring is carried out at 40 ℃-80 ℃; The power of the ultrasound is 20 W-1000 W.

[0013] The mechanical stirring speed is 100 rpm-3000 rpm.

[0014] Optionally, the soluble manganese salt is selected from at least one of manganese nitrate, manganese acetate, and manganese sulfate; The soluble rhenium salt is selected from at least one of ammonium perrhenate, sodium perrhenate, and potassium perrhenate.

[0015] Optionally, the solvents used to prepare the soluble manganese salt solution and the soluble rhenium salt solution are each independently selected from water, ethanol, isopropanol, or ethylene glycol.

[0016] In a second aspect, the present invention provides a catalytic electrode for hydrogen production by PEM water electrolysis, wherein the catalytic electrode for hydrogen production by PEM water electrolysis is obtained by the preparation method described in the first aspect above.

[0017] This invention provides a method for preparing a catalytic electrode for PEM water electrolysis hydrogen production. The method includes: mixing a soluble manganese salt solution and a soluble rhenium salt solution, and applying a combination of ultrasonic and mechanical stirring to the resulting mixture to obtain a homogeneous active layer coating solution; coating the homogeneous active layer coating solution onto the surface of a conductive substrate, and then performing a programmed temperature rise heat treatment to cause thermal decomposition of the homogeneous active layer coating solution on the conductive substrate surface, forming a crystalline rhenium-manganese composite gold oxide catalytic active layer, thus completing the preparation of the catalytic electrode for PEM water electrolysis hydrogen production. Compared with the prior art, this invention has the following advantages: This invention uses manganese-based oxides as the basic active component, combined with rhenium doping to form a non-precious metal catalytic system, completely eliminating dependence on scarce precious metals such as iridium and ruthenium. Manganese and rhenium have wider raw material sources and lower mining and purification costs, significantly reducing the material cost of PEM water electrolysis hydrogen production anode catalysts, providing economic feasibility support for the large-scale promotion of this technology. Through precise doping of rhenium, utilizing its excellent chemical inertness and corrosion resistance, the skeletal stability of manganese oxides is fundamentally enhanced. The introduction of rhenium effectively inhibits the conversion of manganese into high-valence soluble ions under acidic high-potential environments, preventing catalyst structural collapse and loss of active components. Experimental data show that the rhenium-manganese composite gold-based composite metal oxide catalytic electrode provided by this invention, in a 0.5 M H₂SO₄ strongly acidic electrolyte, at 1 A·cm⁻¹… -2 At current density, the accelerated service life reaches up to 80 hours, fully meeting the stability requirements for long-term operation of PEM electrolyzers and solving the core shortcomings of traditional manganese-based non-precious metal catalysts. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A flowchart illustrating the preparation method of the catalytic electrode for PEM water electrolysis hydrogen production provided in an embodiment of the present invention is shown; Figure 2 The diagram shows a comparison of the linear voltammetry curves and oxygen evolution activity of the catalytic electrode for PEM water electrolysis hydrogen production provided in this embodiment of the invention. Figure 3 The following is a comparison diagram of the current step curve activity of the catalytic electrode for PEM water electrolysis hydrogen production provided in the embodiments of the present invention; Figure 4 The 1 A / cm value of the catalytic electrode for PEM water electrolysis hydrogen production provided in this embodiment of the invention is shown. 2 The following is a comparison chart of service life. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention. Furthermore, all other embodiments obtained by those skilled in the art without inventive effort are within the protection scope of the present invention.

[0021] Specific experimental steps or conditions are not specified in the embodiments; they can be performed according to the conventional experimental steps or conditions described in the prior art. Reagents and other instruments used, unless otherwise specified, are all commercially available conventional reagent products. Furthermore, the accompanying drawings are merely illustrative diagrams of the embodiments of the present invention and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore, repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0022] Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of this specification.

[0023] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0024] Among numerous non-precious metal catalytic systems, manganese-based oxides have become a popular research direction for replacing precious metal catalysts due to their wide availability of raw materials, low cost, and inherent oxygen evolution reaction catalytic activity. However, manganese-based oxides have a fundamental technical defect: in the strongly acidic, high-potential environment of a PEM electrolyzer, manganese is easily oxidized into soluble high-valence manganese ions, causing the catalyst's crystal structure to collapse rapidly and the active components to be continuously lost. Its stability is far from meeting the long-term operation requirements of practical applications.

[0025] To improve the acid stability of manganese-based oxides, the industry has tried various element doping modification strategies. However, due to the insufficient compatibility between the doping elements and the structure of manganese-based oxides, these methods can only slightly improve stability and have failed to fundamentally solve the problem of chemical dissolution and deactivation.

[0026] Rhenium has attracted much attention in the materials field due to its excellent chemical inertness and corrosion resistance. In electrocatalysis, it is often used as a structural stabilizer for catalysts to enhance the dissolution and oxidation resistance of catalytic materials. However, existing research on the catalytic applications of rhenium mostly focuses on the modification of noble metal catalytic systems or its use in non-acidic electrolysis environments such as alkaline and neutral environments. A mature technical solution has not yet been developed to use rhenium as a key dopant component and efficiently combine it with manganese-based oxides through suitable preparation processes to systematically solve the intrinsic instability problem of manganese-based oxides in acidic oxygen evolution reactions. Significant research gaps and room for exploration remain in this area. In view of the above-mentioned problems, this invention provides a catalytic electrode for PEM water electrolysis hydrogen production and its preparation method. Rhenium is doped into manganese oxide by high-temperature thermal decomposition of manganese and rhenium precursors in an aerobic environment. The resulting rhenium-manganese composite oxide serves as the catalytic active layer, significantly enhancing the chemical inertness of the manganese oxide framework in acidic media and inhibiting the dissolution and loss of active components. This makes non-precious metal catalysts practically applicable in the strongly acidic environment of PEM electrolyzers. Furthermore, the introduction of rhenium improves stability, optimizes the electronic structure of the material, lowers the oxygen evolution reaction energy barrier, and achieves comprehensive performance enhancement.

[0027] In a first aspect, the present invention provides a method for preparing a catalytic electrode for PEM water electrolysis hydrogen production. A crystalline rhenium-manganese composite gold oxide catalytic active layer is formed on the surface of a conductive substrate by means of a thermal decomposition preparation method. The process is simple and has good repeatability. By controlling the state of the precursor solution and the thermal decomposition program, the composition, structure and loading of the catalyst can be precisely controlled, which is conducive to large-scale production. Figure 1 A flowchart illustrating the preparation method of the catalytic electrode for PEM water electrolysis hydrogen production provided in this embodiment of the invention is shown, as follows: Figure 1 As shown, the preparation method includes: S1. A soluble manganese salt solution and a soluble rhenium salt solution are mixed and subjected to a combination of ultrasonic and mechanical stirring to obtain a homogeneous active layer coating solution. In this step, the soluble manganese salt is selected from at least one of manganese nitrate, manganese acetate, and manganese sulfate; the soluble rhenium salt is selected from at least one of ammonium perrhenate, sodium perrhenate, and potassium perrhenate; the solvent used to prepare the soluble manganese salt solution can be water, ethanol, isopropanol, or ethylene glycol, and the solvent used to prepare the soluble rhenium salt solution can also be water, ethanol, isopropanol, or ethylene glycol.

[0028] This step involves placing the mixture obtained by mixing the soluble manganese salt solution and the soluble rhenium salt solution in an ultrasonic environment. The mixture is ultrasonically treated at a temperature of 40 ℃-80 ℃ and a power of 20 W-1000 W, while mechanical stirring at 100 rpm-3000 rpm can be used simultaneously. The ultrasonic and mechanical stirring process lasts for 30 min-120 min, aiming to completely destroy any possible micelles and achieve uniform miscibility and dispersion of the rhenium and manganese precursors at the molecular level. This results in a highly uniform and stable active layer coating solution, which is a prerequisite for avoiding component segregation during subsequent thermal decomposition and obtaining a homogeneous composite oxide.

[0029] S2. After coating the homogeneous active layer coating liquid onto the surface of the conductive substrate, perform programmed temperature rise heat treatment in an oxidizing atmosphere to cause thermal decomposition of the homogeneous active layer coating liquid on the surface of the conductive substrate, forming a crystalline rhenium-manganese composite gold oxide catalytic active layer.

[0030] In this step, the homogeneous active layer coating liquid can be coated by brushing, spraying, spin coating, or dip-coating. The active layer coating liquid is coated onto the surface of the conductive substrate in any of the above methods, and then subjected to programmed temperature rise heat treatment in an oxidizing atmosphere. Under the action of high temperature, the precursor of manganese (soluble manganese salt) and the precursor of rhenium (soluble rhenium salt) undergo thermal decomposition. Through solid-phase reaction at high temperature, rhenium-manganese composite metal oxide is finally formed, and the rhenium-manganese composite metal oxide forms a stable and firmly attached catalytic active layer.

[0031] In practice, an oxidizing atmosphere is crucial to ensure the full oxidation of metal ions into high-valence oxides (guaranteeing catalytic activity). Slow, programmed heating avoids component volatilization or coating peeling caused by excessively high local temperatures. The programmed heating heat treatment includes: first, heating to 100-150°C at a rate of 1-20°C / min and holding for 10-30 minutes to completely evaporate solvents such as water and ethanol in the coating solution, preventing rapid vaporization of solvents at high temperatures that could cause coating cracking, and simultaneously initially fixing the precursors to the conductive substrate surface; then, heating to 250-600°C at the same rate and holding for 1-8 hours. The high temperature causes the manganese and rhenium precursors to completely decompose and oxidize to generate manganese oxides and rhenium oxides, releasing gaseous products such as nitrogen oxides. The manganese oxides and rhenium oxides further undergo solid-phase reactions at high temperatures to form a structurally stable and firmly adhered rhenium-manganese composite metal oxide catalytic active layer on the conductive substrate surface.

[0032] In some embodiments, when the concentration of total metal ions in the homogeneous active layer coating solution is below 0.01 mol / L, the precursor solution is too dilute, making it difficult to form an effective coating thickness in a single coating, requiring multiple coatings and easily leading to uneven coating. When the concentration is above 5.0 mol / L, the solution viscosity increases sharply, easily causing precursor agglomeration and poor coating fluidity. Subsequent thermal decomposition can easily lead to component segregation or coating cracking, damaging the integrity of the catalyst layer structure. Therefore, in the preferred embodiment of the present invention, the concentration of total metal ions in the homogeneous active layer coating solution is 0.01 mol / L-5.0 mol / L. This concentration range ensures that the thickness of the catalytic active layer formed by thermal decomposition after coating is moderate (neither sparse nor stacked), and the number of active sites is sufficient and uniformly distributed, thereby ensuring that the OER reaction current density is ≥10 mA / cm². 2 The core performance indicators.

[0033] In some embodiments, to ensure that rhenium is uniformly doped into the manganese oxide lattice and forms a stable Re-Mn-O composite structure, thereby enhancing the stability of the manganese oxide framework through the chemical inertness of rhenium and optimizing the surface electronic structure of manganese through electronic regulation, a balance between cost, stability and activity is achieved. In this embodiment of the invention, the molar ratio of rhenium ions to manganese ions in the homogeneous active layer coating solution is controlled to be 0.01-2 (the molar ratio of rhenium ions to manganese ions is 1:99 to 2:1). This ensures that rhenium can fully cover the defects in the manganese oxide lattice, suppress the high-valence dissolution of manganese, and not occupy too many catalytic active sites (manganese oxide is the core active host).

[0034] In some embodiments, the coating method may be brushing, spraying, spin coating, or dip-coating.

[0035] In some embodiments, the conductive substrate is selected from porous titanium or titanium alloy sintered plates, titanium fiber felt, carbon paper, carbon cloth, or glass / ceramic substrates with a conductive oxide film on the surface.

[0036] In some embodiments, the solvents used to prepare the soluble manganese salt solution and the soluble rhenium salt solution are each independently selected from water, ethanol, isopropanol, or ethylene glycol.

[0037] In a second aspect, the present invention provides a catalytic electrode for hydrogen production by PEM water electrolysis, wherein the catalytic electrode for hydrogen production by PEM water electrolysis is obtained by the preparation method described in the first aspect above.

[0038] To enable those skilled in the art to more clearly understand the present invention, the following embodiments are provided to illustrate in detail a catalytic electrode for PEM water electrolysis hydrogen production and its preparation method.

[0039] Example 1 Preparation of the precursor solution: Weigh 0.495 g of manganese nitrate tetrahydrate (Mn(NO3)2·4H2O, as the manganese source) and 0.027 g of ammonium perrhenate (NH4ReO4, as the rhenium source). Dissolve both in a mixed solvent consisting of 5 mL of anhydrous ethanol and 5 mL of deionized water. This mixed solvent was chosen to utilize ethanol to reduce surface tension and improve subsequent wettability and spreading on the titanium substrate. At room temperature (25°C), stir continuously at 400 rpm using a magnetic stirrer for 30 minutes until the solid is completely dissolved, obtaining a clear, transparent, homogeneous solution free of visible particles or phase separation. The total metal ion (Mn + Re) concentration in this mixed precursor solution was calculated to be 0.20 mol / L, with an atomic molar ratio of rhenium (Re) to manganese (Mn) of 5:95.

[0040] Coating solution dispersion treatment: The obtained solution was transferred to a 50 mL PTFE-lined reaction flask. The flask was placed in a constant-temperature ultrasonic water bath at 50℃±2℃. The ultrasonic processor was started, and ultrasonic treatment was performed at a frequency of 40 kHz and an output power of 300 W, while continuous mechanical stirring at 500 rpm was carried out. This combined treatment was performed for 60 minutes.

[0041] Substrate pretreatment and catalyst layer preparation: A porous titanium plate with a thickness of 1.0 mm and a porosity of approximately 35% was selected as the conductive substrate. First, it underwent surface pretreatment: roughening was achieved by sandblasting with 180-mesh quartz sand, followed by alkaline washing at 80°C for 20 minutes in a 10 wt.% NaOH solution to remove oil, and finally etching in a 10 wt.% boiling oxalic acid solution for 2 hours. After treatment, the substrate surface exhibited a uniform silver-gray matte texture. It was then rinsed with deionized water and dried for later use.

[0042] The homogeneous coating solution prepared above was repeatedly and uniformly coated onto the pretreated titanium plate surface (1 cm × 1 cm) using a soft-bristle brush coating method until the desired wet film thickness was achieved. The coated sample was placed horizontally on a clean ceramic sheet and then transferred to a box-type muffle furnace. The following temperature-progressive thermal decomposition was performed under static air atmosphere: the temperature was increased from room temperature to 120°C at a rate of 3°C / min and held at 120°C for 20 minutes to allow for complete solvent evaporation; then the temperature was increased to the target temperature of 450°C at a rate of 3°C / min and calcined at this temperature for 120 minutes. This calcination process completely decomposed and oxidized the organic precursor, converted the inorganic salt into the corresponding metal oxide, and promoted crystallization. After calcination, the power was turned off, and the furnace was allowed to cool naturally to below 80°C before removal, yielding a rhenium-doped manganese-based composite metal oxide catalytic electrode (Re) firmly supported on a porous titanium plate. 0.05 Mn 0.95 O xThe electrode coating is uniform, brownish-black, and firmly bonded to the substrate.

[0043] Example 2 Preparation of the precursor solution: Weigh 0.487 g of manganese nitrate tetrahydrate and 0.054 g of ammonium perrhenate, and dissolve them in 10 mL of the same ethanol-water mixed solvent. The total metal ion concentration of the resulting mixed precursor solution is calculated to be 0.20 mol / L, but the atomic molar ratio of rhenium (Re) to manganese (Mn) is adjusted to 10:90.

[0044] Coating solution dispersion treatment: The process parameters for dispersion treatment (50℃ water bath, 300W ultrasonic power, 500rpm stirring, treatment for 60 minutes) are exactly the same as those in Example 1 to ensure that all variables are consistent except for chemical composition.

[0045] Substrate pretreatment and catalyst layer preparation: Another porous titanium plate was used as the substrate, pretreated in the same manner as in Example 1. The coating method and thermal decomposition procedure (final temperature 450°C, isothermal for 120 minutes) were also strictly consistent with those in Example 1. This comparison ensures that the difference in the final electrode performance is mainly attributable to the difference in rhenium doping amount.

[0046] Example 3 Preparation of precursor solution: Using the same reagents and formulation as in Example 1, a homogeneous precursor solution with Re:Mn=5:95 and a total metal ion concentration of 0.20 mol / L was prepared.

[0047] Pretreatment of the flexible substrate: Commercial hydrophobic carbon paper (0.2 mm thick) was selected as the flexible conductive substrate. To enhance its hydrophilicity and provide more binding sites for the metal oxide coating, it underwent acidification treatment: the carbon paper was immersed in a 65% concentrated nitric acid solution and treated under reflux in an oil bath at 80°C for 60 minutes. After treatment, it was repeatedly rinsed with plenty of deionized water until the effluent was neutral (pH≈7), and then dried in an oven at 80°C for later use. This treatment can introduce oxygen-containing functional groups such as carboxyl groups onto the carbon fiber surface.

[0048] Coating and thermal decomposition of flexible substrates: Due to the porous fibrous structure of carbon paper, an dip-coating method was used for coating. The pretreated carbon paper was vertically immersed in the coating solution, held for 30 seconds, and then pulled out at a constant low speed (2 cm / min) to form a uniform liquid film on its surface. The carbon paper loaded with the coating solution was then suspended in a ventilated area to air dry naturally for 10 minutes. Subsequently, it was laid flat in a quartz boat and placed in a tube furnace. To promote complete oxidation of the precursor and prevent over-oxidation of the carbon matrix at high temperatures, oxygen was introduced as the reaction atmosphere at a flow rate of 50 standard mL / min. The thermal decomposition procedure was adjusted: the heating rate remained at 3 °C / min, and after holding at 120 °C for 20 minutes to remove residual solvent, the final calcination temperature was set to 380 °C and calcined at this temperature for 90 minutes. This slightly lower final temperature was intended to balance the crystallinity of the catalyst with the thermal stability of the carbon substrate. After calcination, the material was naturally cooled to below 150°C in an oxygen atmosphere, and then switched to inert gas protection for cooling to room temperature, ultimately obtaining a flexible rhenium-doped manganese-based composite metal oxide / carbon paper composite electrode.

[0049] Performance testing: Taking Example 1 as an example, the linear voltammetry curve oxygen evolution activity, current step curve activity, and lifespan of the catalytic electrode were tested; the specific test methods are as follows: The oxygen evolution activity of the prepared catalytic anode was analyzed by linear voltammetry and current step curve testing in a three-electrode system. The oxygen evolution activity was further analyzed by testing the prepared anode in a two-electrode system at 1 A·cm⁻¹. -2 Current density accelerated life test.

[0050] Figure 2 The following is a comparison of the linear voltammetric curves and oxygen evolution activity of the catalytic electrode for PEM water electrolysis hydrogen production provided in this embodiment of the invention; as shown in the figure. Figure 2 As shown, the linear current-voltage curves indicate that after Re doping, Re... 0.05 Mn 0.95 O x Both the overpotential and the Tafel slope are lower than those of MnO. x Its oxygen evolution activity has been effectively improved in both thermodynamic and kinetic properties.

[0051] Figure 3 The following is a comparison of the current step curve activity of the catalytic electrode for PEM water electrolysis hydrogen production provided in an embodiment of the present invention; as shown in the figure. Figure 3 As shown, based on the comparison analysis of the same current potential, Re 0.05 Mn 0.95 O x Its oxygen evolution activity is significantly better than that of MnO. x Figure 4The 1 A / cm value of the catalytic electrode for PEM water electrolysis hydrogen production provided in this embodiment of the invention is shown. 2 The following is a comparison chart of service life; as shown. Figure 4 As shown, under high current density, Re 0.05 Mn 0.95 O x Its accelerated lifespan reaches up to 80 hours, far superior to MnO. x 18 hours.

[0052] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0053] For the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, as some steps can be performed in other orders or simultaneously according to the present invention. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and components involved are not necessarily essential to the present invention.

[0054] The present invention provides a detailed description of a PEM water electrolysis hydrogen production catalytic electrode and its preparation method. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for preparing a catalytic electrode for PEM water electrolysis hydrogen production, characterized in that, The preparation method includes: A homogeneous active layer coating solution is obtained by mixing a soluble manganese salt solution and a soluble rhenium salt solution, and then applying a combination of ultrasonic and mechanical stirring to the resulting mixture. After coating the homogeneous active layer coating liquid onto the surface of the conductive substrate, a programmed temperature rise heat treatment is performed in an oxidizing atmosphere to cause the homogeneous active layer coating liquid coated on the surface of the conductive substrate to undergo thermal decomposition, forming a crystalline rhenium-manganese composite gold oxide catalytic active layer.

2. The method for preparing the catalytic electrode for PEM water electrolysis hydrogen production according to claim 1, characterized in that, The concentration of total metal ions in the homogeneous active layer coating solution is 0.01 mol / L-5.0 mol / L.

3. The method for preparing the catalytic electrode for PEM water electrolysis hydrogen production according to claim 1 or 2, characterized in that, In the homogeneous active layer coating solution, the molar ratio of rhenium ions to manganese ions is 0.01-2.

4. The method for preparing the catalytic electrode for PEM water electrolysis hydrogen production according to claim 1, characterized in that, The coating method is brushing, spraying, spin coating, or dip-coating.

5. The method for preparing the catalytic electrode for PEM water electrolysis hydrogen production according to claim 1, characterized in that, The thermal decomposition is carried out in an oxidizing atmosphere. The programmed temperature rise heat treatment includes: heating to 100 ℃-150 ℃ at a heating rate of 1 ℃ / min to 20 ℃ / min, holding at that temperature for 10 min to 30 min, and then continuing to heat to 250 ℃-600 ℃ at a heating rate of 1 ℃ / min to 20 ℃ / min, holding at that temperature for 1 h to 8 h.

6. The method for preparing the catalytic electrode for PEM water electrolysis hydrogen production according to claim 1, characterized in that, The conductive substrate is selected from porous titanium or titanium alloy sintered plates, titanium fiber felt, carbon paper, carbon cloth, or glass / ceramic substrates with a conductive oxide film on the surface.

7. The method for preparing the catalytic electrode for PEM water electrolysis hydrogen production according to claim 1, characterized in that, The duration of ultrasonic and mechanical stirring is 30 min-120 min; Continuous stirring is carried out at 40 ℃-80 ℃; The power of the ultrasound is 20 W-1000 W; The mechanical stirring speed is 100 rpm-3000 rpm.

8. The method for preparing the catalytic electrode for PEM water electrolysis hydrogen production according to claim 1, characterized in that, The soluble manganese salt is selected from at least one of manganese nitrate, manganese acetate, and manganese sulfate; The soluble rhenium salt is selected from at least one of ammonium perrhenate, sodium perrhenate, and potassium perrhenate.

9. The method for preparing the catalytic electrode for PEM water electrolysis hydrogen production according to claim 1 or 8, characterized in that, The solvents used to prepare the soluble manganese salt solution and the soluble rhenium salt solution are each independently selected from water, ethanol, isopropanol, or ethylene glycol.

10. A catalytic electrode for PEM water electrolysis to produce hydrogen, characterized in that, The catalytic electrode for PEM water electrolysis hydrogen production is obtained by any of the preparation methods described in claims 1-9.

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