A RuO2 / MnO2 heterostructure material, its preparation method, and its applications

Abstract

The application discloses a RuO2 / MnO2 heterostructure material and a preparation method and application thereof, and belongs to the technical field of functional materials; the application is used for solving the technical problems of low activity and insufficient stability of an electrolytic seawater chlorine evolution reaction catalytic material in the prior art; the preparation method of the RuO2 / MnO2 heterostructure material comprises the following steps: mixing soluble ruthenium salt, soluble manganese salt and an oxidizing agent in water to obtain a mixed solution, performing a hydrothermal reaction, washing, drying, and obtaining a precursor; the precursor is heated from room temperature to 100-250 DEG C in an air atmosphere and is kept for 3-5 hours to obtain the RuO2 / MnO2 heterostructure material; in the RuO2 / MnO2 heterostructure material, the MnO2 is gamma-MnO2; in the RuO2 / MnO2 heterostructure material, the RuO2 is amorphous RuO2; the preparation method of the RuO2 / MnO2 heterostructure material has the characteristics of simple operation and cost reduction, and the prepared RuO2 / MnO2 heterostructure material exhibits excellent catalytic activity and stability in the electrolytic seawater chlorine evolution reaction.

Description

Technical Field

[0001] This invention relates to the field of functional materials technology, specifically to a RuO2 / MnO2 heterostructure material, its preparation method, and its applications. Background Technology

[0002] Seawater is the most abundant natural chlorine resource on Earth. Electrolysis of seawater to produce active chlorine not only eliminates the need for brine purification, reducing raw material costs, but also enables on-site resource utilization. The core of this method is the chlorine evolution reaction, which directly converts Cl₂ into chlorine. - The conversion of chlorine into active chlorine has attracted widespread attention due to its advantages such as simple operation, mild and readily available reaction conditions, and reliance on renewable energy. Active chlorine (mainly including Cl2, HClO, and ClO) is an effective pathway for this process. - As a highly efficient and economical disinfectant, chlorine has wide applications in drinking water purification, medical and health care, and aquaculture. Commonly used chlorine evolution catalysts mainly include noble metal-based materials (such as RuO2 and IrO2) and transition metal oxides (such as MnO2 and CO3O4). RuO2 possesses excellent electronic conductivity and chlorine evolution catalytic activity, but crystalline RuO2 is prone to dissolution and loss under strong oxidizing and high-salt environments, resulting in insufficient stability; simultaneously, pure RuO2 has limited ability to inhibit OER (oxidative chlorination). MnO2, as a low-cost transition metal oxide, has good chemical stability and certain chlorine evolution catalytic activity, but its catalytic activity is far lower than that of RuO2, making it difficult to meet the requirements of efficient electrolysis. Therefore, there is an urgent need to develop a new material that can solve the problems of low activity and insufficient stability of existing active chlorine evolution catalysts for seawater electrolysis.

[0003] Chinese patent CN116377505A discloses a MnO2 / RuO2 heterogeneous oxygen evolution reaction electrocatalyst, its preparation method, and its application. The preparation steps of the MnO2 / RuO2 heterogeneous oxygen evolution reaction electrocatalyst include: ultrasonically homogenizing α-MnO2 powder in deionized water, adding RuCl3 aqueous solution, stirring, drying, and calcining the composite product at high temperature; the composite product is then etched, filtered, and dried to obtain the final product. This invention utilizes the structurally stable α-MnO2 as a support to load noble metal oxide RuO2 nanoparticles, thereby improving the utilization efficiency and stability of the noble metal oxide active material. However, the MnO2 / RuO2 heterogeneous oxygen evolution reaction electrocatalyst prepared by this invention exhibits good stability in the oxygen evolution reaction, but not in the chlorine evolution reaction. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a RuO2 / MnO2 heterostructure material, its preparation method, and its application, solving the issues of low catalyst activity and insufficient stability in the electrolysis of seawater to produce active chlorine. The preparation method of the RuO2 / MnO2 heterostructure material proposed in this invention is characterized by simple operation and reduced cost. The prepared RuO2 / MnO2 heterostructure material meets the requirements for the electrolysis of seawater to produce active chlorine due to its high catalytic activity, good stability, and low overpotential.

[0005] To achieve the above objectives, the present invention provides a method for preparing RuO2 / MnO2 heterostructure materials, comprising the following steps:

[0006] Step (1) Soluble ruthenium salt, soluble manganese salt and oxidant are mixed in water to obtain a mixed solution, which is then subjected to a hydrothermal reaction, washed and dried to obtain the precursor;

[0007] Step (2) The precursor is heated from room temperature to 100-250℃ in air atmosphere and kept at that temperature for 3-5 hours to obtain RuO2 / MnO2 heterostructure material;

[0008] In the RuO2 / MnO2 heterostructure material, MnO2 is γ-MnO2;

[0009] In the RuO2 / MnO2 heterostructure material, RuO2 is amorphous RuO2;

[0010] In the RuO2 / MnO2 heterostructure material, both RuO2 and MnO2 are nanoscale.

[0011] Preferably, in step (1), the soluble ruthenium salt is RuCl3; the soluble manganese salt is MnSO4; and the oxidant is (NH4)2S2O8.

[0012] Preferably, in step (1), the molar ratio of soluble ruthenium salt, soluble manganese salt and oxidant is (1-2):(4-5):(3-6).

[0013] Preferably, in step (1), the total molar concentration of soluble ruthenium salt and soluble manganese salt in the mixture is 0.01-0.05 mol / L.

[0014] Preferably, in step (1), the temperature of the hydrothermal reaction is 80-100℃ and the reaction time is 22-26h.

[0015] Preferably, in step (2), the drying temperature is 60-70℃ and the drying time is 6-8h.

[0016] Preferably, in step (2), the heating rate during the heating process is 5-7℃ / min.

[0017] Preferably, in step (1), the washing agent is anhydrous ethanol.

[0018] Preferably, in step (2), the RuO2 / MnO2 heterostructure material is specifically an amorphous RuO2 / crystalline MnO2 heterostructure material.

[0019] Preferably, in step (2), the RuO2 in the RuO2 / MnO2 heterostructure material is amorphous RuO2.

[0020] A RuO2 / MnO2 heterostructure material is prepared by the method for preparing RuO2 / MnO2 heterostructure material.

[0021] A chlorine evolution catalyst material, comprising the aforementioned RuO2 / MnO2 heterostructure material.

[0022] A seawater electrolysis chlorine production reactor, comprising the aforementioned chlorine evolution catalyst material.

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

[0024] 1. This invention provides a method for preparing RuO2 / MnO2 heterostructure materials. This method is easy to operate, requires minimal production equipment, and is conducive to large-scale industrial production. It also reduces the amount of precious metals used, lowering production costs. The RuO2 / MnO2 heterostructure material prepared by this invention exhibits high catalytic activity and excellent corrosion resistance as a catalyst in the preparation of activated chlorine from seawater. It maintains high stability even at high current densities, and its catalytic activity is not easily attenuated, effectively extending the catalyst's lifespan. The RuO2 / MnO2 heterostructure material provided by this invention is actually an amorphous RuO2 / crystalline MnO2 heterostructure material. By controlling the phase structure and interfacial characteristics of the material, a balance between high chlorine evolution activity and high stability is achieved. Furthermore, the material is simple to prepare and the preparation method is controllable.

[0025] 2. The RuO2 in the RuO2 / MnO2 heterostructure material prepared by this invention is amorphous. Its amorphous atomic arrangement structure endows the material with a larger specific surface area and abundant surface active sites, which can significantly enhance the adsorption and activation capacity of Cl⁻, thereby enhancing the kinetics of the catalytic chlorine evolution reaction. MnO2 is crystalline, with a more stable structure and a crystal form of γ-MnO2. Its internal tunnel structure contains abundant tunnels that can effectively form "confined diffusion channels," which both accelerate the migration of Cl⁻ from seawater to the catalytic active site Ru and prevent chlorine from desorbing too quickly. The tunnel structure of γ-MnO2 has better tolerance and is less prone to lattice collapse due to Cl⁻ embedding or potential fluctuations after being combined with RuO2. The stronger Ru-O-Mn bond network between γ-MnO2 and RuO2 forms a "protective barrier" to prevent corrosive ions from penetrating the RuO2 lattice, thereby enhancing the overall stability of the material. At the same time, the high redox content in γ-MnO2 has a strong redox effect on Mn 3+ / Mn 4+ It can replenish electrons in real time, preventing Ru from being over-oxidized and dissolved at high potentials, thus extending the service life of RuO2 / MnO2 heterostructure materials as chlorine evolution reaction catalysts. Amorphous RuO2 can also alleviate the crystal phase transformation and particle agglomeration phenomena of the material during long-term electrolysis, further ensuring the durability of the catalyst's catalytic performance in complex seawater environments.

[0026] 3. The RuO2 and MnO2 in the RuO2 / MnO2 heterostructure material prepared by this invention are both nanoscale, and the amorphous nanostructured RuO2 particles typically have a large specific surface area, providing more active sites and benefiting the catalytic reaction. Due to its abundant surface defects and high specific surface area, it exhibits higher catalytic activity and better cycle stability. Furthermore, the adsorption and reaction capacity of the amorphous nanostructured RuO2 for chloride ions is enhanced by the nanosize effect, enabling rapid reaction kinetics. Simultaneously, the crystalline MnO2 helps improve charge transport efficiency and structural stability, further enhancing the efficiency and stability of the RuO2 / MnO2 heterostructure material in the catalytic chloride evolution reaction. The RuO2 / MnO2 heterostructure material prepared by this invention exhibits a significantly lower overpotential, meaning that a lower applied voltage is required at the same current density, helping to reduce energy consumption and meeting the requirements of green and sustainable development. This provides strong material support for the industrialization of seawater electrolysis to produce active chlorine. In the chloride evolution reaction, the RuO2 / MnO2 heterostructure material prepared by this invention achieves a current density of 10 mA / cm². 2 At that time, the overpotential was only 26mV, and it could withstand 100mA / cm 2It can operate continuously for up to 500 hours at the highest current density. The hypochlorous acid solution produced by electrolyzing seawater using RuO2 / MnO2 heterostructure materials driven by solar photovoltaic panels can effectively disinfect Escherichia coli, Staphylococcus aureus, and Vibrio alginolyticus. Attached Figure Description

[0027] Figure 1 The image shows the XRD pattern of the RuO2 / MnO2 heterostructure material obtained in Example 3 of this invention.

[0028] Figure 2 This is a TEM image of the RuO2 / MnO2 heterostructure material obtained in Example 3 of the present invention;

[0029] Figure 3 This is the selected area electron diffraction pattern of the RuO2 / MnO2 heterostructure material obtained in Example 3 of the present invention;

[0030] Figure 4 The LSV diagram of the RuO2 / MnO2 heterostructure material obtained in Example 3 of this invention;

[0031] Figure 5 This is a selective test diagram of the chlorine evolution reaction of the RuO2 / MnO2 heterostructure material obtained in Example 3 of the present invention;

[0032] Figure 6 The RuO2 / MnO2 heterostructure material obtained in Example 3 of this invention is at 100 mA / cm 2 Stability test results at current density;

[0033] Figure 7 The precursor in Example 3 of this invention and its LSV diagram at different calcination temperatures;

[0034] Figure 8 The precursor in Example 3 of this invention and its XRD patterns at different calcination temperatures;

[0035] Figure 9 This is a graph showing the precursor in Example 3 of the present invention and its chlorine evolution selectivity at different calcination temperatures;

[0036] Figure 10 This image shows the sterilization process of the RuO2 / MnO2 heterostructure material obtained in Example 3 of this invention after electrolysis of seawater to prepare hypochlorous acid disinfectant under the drive of a solar photovoltaic panel. Detailed Implementation

[0037] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] Example 1

[0039] This embodiment provides a method for preparing RuO2 / MnO2 heterostructure materials, including the following steps:

[0040] Step (1) Add RuCl3, MnSO4 and (NH4)2S2O8 to water in a molar ratio of 1:4:3, stir evenly to obtain a mixed solution, carry out hydrothermal reaction at 80℃ for 26h, wash 3 times with anhydrous ethanol, and dry in a drying oven at 60℃ for 8h to obtain the precursor.

[0041] Step (2) The precursor is placed in a tube furnace and heated from room temperature to 100°C in air atmosphere at a heating rate of 5°C / min. The temperature is then maintained at this temperature for 5 hours to obtain RuO2 / MnO2 heterostructure material.

[0042] The total molar concentration of RuCl3 and MnSO4 in the mixture was 0.01 mol / L.

[0043] In the RuO2 / MnO2 heterostructure material, MnO2 is γ-MnO2;

[0044] In the RuO2 / MnO2 heterostructure material, RuO2 is amorphous RuO2;

[0045] In the RuO2 / MnO2 heterostructure material, both RuO2 and MnO2 are nanoscale.

[0046] Example 2

[0047] This embodiment provides a method for preparing RuO2 / MnO2 heterostructure materials, including the following steps:

[0048] Step (1) Add RuCl3, MnSO4 and (NH4)2S2O8 to water in a molar ratio of 1.2:4.2:3.7, stir evenly to obtain a mixed solution, carry out hydrothermal reaction at 85℃ for 25h, wash three times with anhydrous ethanol, and dry in a drying oven at 62℃ for 7.5h to obtain the precursor;

[0049] Step (2) The precursor is placed in a tube furnace and heated from room temperature to 150°C in air atmosphere at a heating rate of 5.5°C / min. The temperature is then maintained at this temperature for 4.5 h to obtain RuO2 / MnO2 heterostructure material.

[0050] The total molar concentration of RuCl3 and MnSO4 in the mixture was 0.02 mol / L.

[0051] In the RuO2 / MnO2 heterostructure material, MnO2 is γ-MnO2;

[0052] In the RuO2 / MnO2 heterostructure material, RuO2 is amorphous RuO2;

[0053] In the RuO2 / MnO2 heterostructure material, both RuO2 and MnO2 are nanoscale.

[0054] Example 3

[0055] This embodiment provides a method for preparing RuO2 / MnO2 heterostructure materials, including the following steps:

[0056] Step (1) Add RuCl3, MnSO4 and (NH4)2S2O8 to water in a molar ratio of 1.5:4.5:4.4, stir evenly to obtain a mixture, carry out hydrothermal reaction at 90℃ for 24h, wash three times with anhydrous ethanol, and dry in a drying oven at 65℃ for 7h to obtain the precursor.

[0057] Step (2) The precursor is placed in a tube furnace and heated from room temperature to 200°C in air at a rate of 6°C / min, and held at this temperature for 4 hours to obtain the RuO2 / MnO2 heterostructure material (the LSV diagram of the RuO2 / MnO2 heterostructure material is shown in the figure). Figure 4 As shown, the theoretical voltage is 1.79V).

[0058] The total molar concentration of RuCl3 and MnSO4 in the mixture was 0.03 mol / L.

[0059] In the RuO2 / MnO2 heterostructure material, MnO2 is γ-MnO2;

[0060] In the RuO2 / MnO2 heterostructure material, RuO2 is amorphous RuO2;

[0061] In the RuO2 / MnO2 heterostructure material, both RuO2 and MnO2 are nanoscale.

[0062] Example 4

[0063] This embodiment provides a method for preparing RuO2 / MnO2 heterostructure materials, including the following steps:

[0064] Step (1) Add RuCl3, MnSO4 and (NH4)2S2O8 to water in a molar ratio of 1.7:4.7:5.1, stir evenly to obtain a mixed solution, carry out hydrothermal reaction at 95℃ for 23h, wash three times with anhydrous ethanol, and dry at 67℃ for 6.5h in a drying oven to obtain the precursor;

[0065] Step (2) The precursor is placed in a tube furnace and heated from room temperature to 225°C in an air atmosphere at a heating rate of 6.5°C / min. The temperature is then maintained at this temperature for 3.5 h to obtain RuO2 / MnO2 heterostructure material.

[0066] The total molar concentration of RuCl3 and MnSO4 in the mixture was 0.04 mol / L.

[0067] In the RuO2 / MnO2 heterostructure material, MnO2 is γ-MnO2;

[0068] In the RuO2 / MnO2 heterostructure material, RuO2 is amorphous RuO2;

[0069] In the RuO2 / MnO2 heterostructure material, both RuO2 and MnO2 are nanoscale.

[0070] Example 5

[0071] This embodiment provides a method for preparing RuO2 / MnO2 heterostructure materials, including the following steps:

[0072] Step (1) Add RuCl3, MnSO4 and (NH4)2S2O8 to water in a molar ratio of 2:5:6, stir evenly to obtain a mixed solution, carry out hydrothermal reaction at 100℃ for 22h, wash 3 times with anhydrous ethanol, and dry in a drying oven at 70℃ for 6h to obtain the precursor.

[0073] Step (2) The precursor is placed in a tube furnace and heated from room temperature to 250°C in an air atmosphere at a heating rate of 7°C / min. The temperature is then maintained at this temperature for 3 hours to obtain RuO2 / MnO2 heterostructure material.

[0074] The total molar concentration of RuCl3 and MnSO4 in the mixture was 0.05 mol / L.

[0075] In the RuO2 / MnO2 heterostructure material, MnO2 is γ-MnO2;

[0076] In the RuO2 / MnO2 heterostructure material, RuO2 is amorphous RuO2;

[0077] In the RuO2 / MnO2 heterostructure material, both RuO2 and MnO2 are nanoscale.

[0078] Comparative Example 1

[0079] The difference between this comparative example and Example 3 is that the RuO2 / MnO2 heterostructure material used in this comparative example is the MnO2 / RuO2 heterostructure electrocatalyst for oxygen evolution reaction disclosed in Example 1 of Chinese patent application CN116377505A.

[0080] Comparative Example 2

[0081] The difference between this comparative example and Example 3 is that the calcination temperature in step (2) is different. In this comparative example, the calcination temperature is 300℃ (XRD pattern of the prepared RuO2 / MnO2 heterostructure material, specifically as shown in the figure). Figure 8 (As shown); other conditions remain unchanged.

[0082] Comparative Example 3

[0083] The difference between this comparative example and Example 3 is that in step (1), an equimolar amount of RuCl3·3H2O containing water of crystallization is used instead of RuCl3; other conditions remain unchanged.

[0084] In this invention, RuCl3·3H2O is from Shanghai Aladdin Biochemical Technology Co., Ltd.; RuCl3 is from Shanghai Maclean Biochemical Technology Co., Ltd.; (NH4)2S2O8 is from Shanghai Aladdin Biochemical Technology Co., Ltd.; MnSO4 is from Shanghai Maclean Biochemical Technology Co., Ltd.; and the others are commercially available products.

[0085] Performance testing:

[0086] Take 1 mg of each of the preparations from Examples 1-5 and Comparative Examples 1-3 and add them to 210 μl of a mixed solution (containing 100 μl of anhydrous ethanol, 100 μl of deionized water, and 10 μl of 5 wt% Nafion aqueous solution). After ultrasonic dispersion, use the resulting solution as catalyst ink. Drop 50 μl of the catalyst ink onto a 1 cm thick surface. 2 Electrodes were obtained by air-drying the carbon paper, and were labeled as samples 1-8. Corresponding tests were then performed, and the results are shown below:

[0087] (1) Three-electrode test: Samples 1-8 were used as working electrodes, seawater as electrolyte, Ag / AgCl as reference electrode, and platinum sheet as counter electrode. CHI760E electrochemical workstation was used as the test instrument. The test was carried out at room temperature and pressure. The specific test results are shown in Table 1.

[0088] (2) Constant current test: In the three-electrode system containing samples 1-8, seawater was used as the electrolyte, and constant current tests were performed on samples 1-8 under normal temperature and pressure conditions. A CHI760E electrochemical workstation was used as the testing instrument to monitor and record a constant current density of 100 mA / cm². 2 The stable operating time of samples 1-8 is shown in Table 1.

[0089] Table 1

[0090] As shown in Table 1, the RuO2 / MnO2 heterostructure material prepared in this invention exhibits durability and good catalytic performance when used as a catalyst for the chlorination reaction in seawater electrolysis, significantly outperforming samples 6-8. The RuO2 / MnO2 heterostructure material prepared in Example 3 demonstrates the best performance, with a current density of 10 mA / cm². 2 At this time, the overpotential was only 26 mV, demonstrating excellent catalytic performance in the chlorine evolution reaction. RuO2 is a key active component in the electrocatalytic chlorine evolution reaction, playing a crucial role in the catalytic process, and its catalytic performance directly affects the reaction activity and efficiency. The preparation in Comparative Example 1 contained α-MnO2 and RuO2, with α-MnO2 only having RuO2 loaded on its surface, resulting in uneven dispersion, weak interface, low electron transport efficiency, and fewer active sites. Therefore, the reaction kinetics were slow, requiring a higher overpotential; that is, the overpotential of Sample 6 was higher than that of Sample 3. The poor interface effect between the two made the material susceptible to corrosion during electrocatalysis, resulting in poor durability. Therefore, Sample 6 had a low overpotential at 100 mA / cm². 2 The constant current test can withstand a shorter time value than that of sample 3. The XRD pattern of the RuO2 / MnO2 heterostructure material prepared in Comparative Example 2 is shown below. Figure 8 As shown, from Figure 8 It is known that calcination at higher temperatures transforms amorphous RuO2 into crystalline RuO2, which reduces the number of active sites and weakens the buffering capacity, failing to mitigate the damage to the overall structure caused by volume changes during the reaction. Therefore, the stability of sample 7 corresponding to Comparative Example 2 is lower than that of sample 3 corresponding to Example 3. Sample 7 at 100 mA / cm 2 The time value that the constant current test can stably withstand is less than that of sample 3; calcination reduces the number of active sites, and crystallization is not conducive to interfacial coupling, resulting in poorer electron transport and intermediate adsorption, and an increased overpotential. Therefore, the overpotential of sample 7 is higher than that of sample 3. The difference between Comparative Example 3 and Example 3 is that an equimolar amount of RuCl3·3H2O containing water of crystallization is used instead of RuCl3. The water of crystallization makes RuO2 itself more fragile, weakens interfacial interaction, and reduces electron conduction efficiency, thereby increasing the overpotential of sample 8; sample 3 at 100 mA / cm 2The constant current test can withstand a longer time value than sample 8.

[0091] (2) Selectivity test of chlorine evolution reaction: Seawater was filtered through a 0.22 μm filter membrane to remove suspended particulate matter; Ag-type ion exchange resin column and activated carbon adsorption column were passed through to remove impurities, and pretreated seawater was obtained. 60 mL of pretreated seawater was used as electrolyte and transferred into the anode chamber of the ion membrane-separated H-type electrolytic cell. An equal volume of 60 mL of seawater was added to the cathode chamber. The electrolyte in the anode chamber was purged with argon gas for 20 minutes to remove dissolved oxygen. Subsequently, samples 3 and 6-8 were used as working electrodes, a platinum sheet as the counter electrode, and an Ag / AgCl electrode as the reference electrode. Under room temperature conditions, a current density of 10 mA / cm² was applied and the electrolysis time was accurately controlled for 10 min. Immediately after electrolysis, 2 mL of electrolyte from the anode chamber was transferred and quickly injected into a volumetric flask containing excess potassium iodide aqueous solution. The solution was then titrated with 0.01 mol / L sodium thiosulfate aqueous solution. When the solution turned pale yellow, starch indicator was added, and titration continued until the blue color just disappeared. The selectivity (%) of the chlorine evolution reaction was represented by recording the percentage of the experimental chlorine production rate relative to the theoretical electrochemical chlorine production rate. Specific test results are shown in Table 2.

[0092] Table 2

[0093] As can be seen from the data in Table 2, the RuO2 / MnO2 heterostructure material prepared in this invention exhibits significantly better selectivity for the electrocatalytic chlorine evolution reaction than the comparative materials. Specifically, at a low current density of 10 mA / cm², the chlorine evolution reaction selectivity of sample 3 is as high as 91.78%, significantly higher than that of sample 6 (42.34%), sample 7 (87.43%), and sample 8 (86.57%). While the chlorine evolution reaction selectivity of sample 3 decreases slightly with increasing current density, it is still better than that of samples 6-8. In contrast, the selectivity of the comparative materials is significantly lower under the same conditions, and the decrease is particularly pronounced at a high current density of 100 mA / cm². This indicates that the RuO2 / MnO2 heterostructure material of this invention can more effectively suppress the competitive oxygen evolution reaction and improve the electrocatalytic yield of active chlorine.

[0094] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

[0095] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," 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, 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.

[0096] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for preparing a RuO2 / MnO2 heterostructure material, characterized in that, Includes the following steps: Step (1) Soluble ruthenium salt, soluble manganese salt and oxidant are mixed in water to obtain a mixed solution, which is then subjected to a hydrothermal reaction, washed and dried to obtain the precursor; Step (2) The precursor is heated from room temperature to 100-250℃ in air atmosphere and kept at that temperature for 3-5 hours to obtain RuO2 / MnO2 heterostructure material; In the RuO2 / MnO2 heterostructure material, MnO2 is γ-MnO2; In the RuO2 / MnO2 heterostructure material, RuO2 is amorphous RuO2; In the RuO2 / MnO2 heterostructure material, both RuO2 and MnO2 are nanoscale.

2. The method for preparing a RuO2 / MnO2 heterostructure material according to claim 1, characterized in that, In step (1), the soluble ruthenium salt is RuCl3; the soluble manganese salt is MnSO4; and the oxidant is (NH4)2S2O8.

3. The method for preparing a RuO2 / MnO2 heterostructure material according to claim 1, characterized in that, In step (1), the molar ratio of soluble ruthenium salt, soluble manganese salt and oxidant is (1-2):(4-5):(3-6).

4. The method for preparing a RuO2 / MnO2 heterostructure material according to claim 1, characterized in that, In step (1), the total molar concentration of soluble ruthenium salt and soluble manganese salt in the mixture is 0.01-0.05 mol / L.

5. The method for preparing a RuO2 / MnO2 heterostructure material according to claim 1, characterized in that, In step (1), the temperature of the hydrothermal reaction is 80-100℃ and the reaction time is 22-26h.

6. The method for preparing a RuO2 / MnO2 heterostructure material according to claim 1, characterized in that, In step (2), the drying temperature is 60-70℃ and the drying time is 6-8h.

7. The method for preparing a RuO2 / MnO2 heterostructure material according to claim 1, characterized in that, In step (2), the heating rate during the heating process is 5-7℃ / min.

8. A RuO2 / MnO2 heterostructure material, characterized in that, It is prepared by the method for preparing RuO2 / MnO2 heterostructure material according to any one of claims 1-7.

9. A chlorine evolution catalyst, characterized in that, Including the RuO2 / MnO2 heterostructure material as described in claim 8.

10. A reactor for producing chlorine by electrolysis of seawater, characterized in that, Includes the chlorine evolution catalyst material as described in claim 9.

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