IrxCo3-xO4 / Ir-Co3O4 heterostructure electrocatalyst as well as preparation method and application of IrxCo3-xO4 / Ir-Co3O4 heterostructure electrocatalyst in combination with co-deposition and defect regulation

Abstract

The invention discloses an IrxCo3-xO4 / Ir-Co3O4 heterostructure electrocatalyst as well as a preparation method and application of the IrxCo3-xO4 / Ir-Co3O4 heterostructure electrocatalyst in combination with co-deposition and defect regulation, and belongs to the technical field of catalyst preparation. Comprising the following steps: dissolving an iridium-containing compound and a cobalt-containing compound in deionized water to prepare a precursor solution, and carrying out cathode co-deposition treatment in a three-electrode system; calcining the sample, creating abundant anion and cation vacancies in the material through plasma treatment, and calcining again to eliminate oxygen ion vacancies; the treated sample is soaked in an IrCl3 solution, heat treatment is carried out after the solvent is evaporated to dryness, and the IrxCo < 3-x > O < 4 > / Ir-Co3O4 heterostructure electrocatalyst is prepared. The heterostructure catalyst can effectively improve an electronic structure around an Ir active center, strengthen interaction of a metal-metal oxide carrier, inhibit over-oxidation of atoms in the Ir active center, greatly improve the activity and stability of the catalyst, and improve the catalytic activity of the catalyst. Therefore, the technical problems of low activity, low quality activity and poor stability of a noble metal-based catalyst in the prior art can be effectively solved.

Description

Technical Field

[0001] This invention belongs to the field of catalyst preparation technology, specifically relating to an Ir x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalysts, their preparation methods and applications based on co-deposition and bonding defect regulation. Background Technology

[0002] With the increasing global demand for clean energy, hydrogen production through water electrolysis using renewable energy is considered an important path to achieving sustainable development. Among these technologies, acidic water electrolysis shows great application potential due to its high efficiency, high current density, compact equipment structure, and high purity of the produced hydrogen. However, the large-scale commercial application of this technology is severely limited by the oxygen evolution reaction (OER). OER is a complex process involving the transfer of four electrons, characterized by slow kinetics and high overpotential, becoming a bottleneck restricting the overall efficiency of water splitting.

[0003] Currently, iridium (Ir)-based and ruthenium (Ru)-based noble metal oxides are recognized as OER electrocatalysts capable of maintaining high activity and stability in strongly acidic and corrosive environments. However, the scarcity and high cost of noble metals such as iridium greatly limit their widespread application. Therefore, developing catalytic materials that can maximize the utilization of noble metal atoms, thereby significantly reducing the amount of noble metals used while ensuring high performance, is one of the core challenges currently facing this field.

[0004] One effective strategy is to combine trace amounts of noble metals with inexpensive transition metals (such as cobalt, Co) to construct catalysts with heterostructures, aiming to improve the mass-specific activity of noble metals through synergistic effects between components. In existing technologies, the preparation of such noble metal-based catalysts often employs traditional hydrothermal or co-precipitation methods combined with high-temperature annealing. A typical process involves mixing a noble metal salt with a non-noble metal salt solution, obtaining a precursor through hydrothermal reaction or co-precipitation, followed by high-temperature calcination to obtain a metal oxide catalyst, and finally loading the catalyst powder onto an electrode substrate using physical methods such as spraying or drop coating. However, this method has several inherent drawbacks: First, during high-temperature calcination, noble metals are prone to agglomeration, forming larger particles, leading to a reduction in the number of active sites and low utilization of noble metals; second, physical coating results in weak bonding between the catalyst and the substrate, making the catalyst prone to detachment from the electrode surface during vigorous OER reactions (especially oxygen evolution bubble impacts under acidic conditions), leading to rapid catalytic performance degradation and poor stability. These issues collectively result in low precious metal specific activity in the final catalyst and limited device lifespan, making it difficult to meet the application requirements of high-quality integrated electrolysis devices. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide an Ir x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalysts and their co-deposition bonding defect control preparation method and applications enable the direct construction of highly active and stable noble metal-based catalysts on conductive substrates. This method should achieve high dispersion of noble metal atoms, effectively preventing their aggregation and strengthening the bonding force between the catalyst and the substrate, fundamentally solving the technical problems of low noble metal specific activity and poor electrode stability in existing technologies.

[0006] To achieve the above objectives, the present invention employs the following technical solution: In the first aspect, this application discloses a method for preparing Ir by controlling defects in co-deposition. x Co 3-x A method for developing an O4 / Ir-Co3O4 heterostructure electrocatalyst includes the following steps: 1) Dissolve the iridium-containing compound and the cobalt-containing compound together in water, mix thoroughly, and prepare a transparent solution A; 2) Using the transparent solution A obtained in step 1) as the electrolyte, a cathode co-deposition treatment was performed in a three-electrode system, followed by drying to obtain sample A; 3) Sample A was calcined once, then plasma-cleaned to create ion vacancy defects, and then calcined a second time to eliminate oxygen ion vacancies, thus obtaining sample B. 4) Dissolve the iridium-containing compound in water, mix thoroughly, and prepare a transparent solution B; 5) Immerse sample B obtained in step 3) in transparent solution B, then dry to remove the solvent, and then perform three calcination treatments to obtain Ir. x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalyst.

[0007] Furthermore, this application also proposes that, in step 1), the iridium-containing compound is IrCl4 powder, and the cobalt-containing compound is Co(NO3)2. . 6H2O powder; IrCl4 powder, Co(NO3)2 . The ratio of 6H2O powder to water is (20-40) mg: (1-2) g: (30-50) mL; in step 1), thorough mixing is achieved by stirring under ultrasonic conditions for 10-20 min.

[0008] The preferred embodiment of this application constructs a highly synergistic solution preparation system by selecting specific iridium- and cobalt-containing compounds, strictly limiting their proportions, and implementing an ultrasonic mixing process. The stable solubility of IrCl4 powder provides a continuous and uniform supply of iridium ions for co-deposition, while Co(NO3)2... . The rapid dissociation of 6H₂O powder facilitated homogeneous mixing with iridium ions. The set dosage ratio range optimized ion migration efficiency and film composition matching, while ultrasonic stirring eliminated local concentration differences through cavitation. This operation ensured the synchronous adsorption and deposition of metal ions during cathode co-deposition, effectively suppressing the risk of agglomeration caused by excessively high local concentrations, and laying the foundation for the subsequent preparation of heterogeneous precursor films with uniform structures. Furthermore, this application also proposes that, in step 2), the three-electrode system includes: The acid-treated platinum-titanium plating felt is sandwiched between platinum sheet electrode clips to serve as the working electrode. A carbon rod is used as the counter electrode. A silver / silver chloride electrode is used as a reference electrode.

[0009] Acid treatment refers to the chemical cleaning of the substrate surface by means of an acidic solution, which can be carried out using common inorganic acid solutions such as dilute hydrochloric acid or dilute nitric acid. Its purpose is to remove surface oxides and organic contaminants, and increase micro-roughness to promote uniform nucleation and attachment of catalyst precursors.

[0010] The platinum electrode clip is a metal clamping device used to fix the working electrode, and can be made of platinum or platinum-plated metal. The carbon rod can be a rod-shaped conductor made of high-purity graphite material, which can provide a chemically inert and stable current channel, avoiding the counter electrode from participating in side reactions and contaminating the electrolyte. The silver / silver chloride electrode is specifically a reference electrode structure based on a silver wire substrate coated with a silver chloride layer. Its electrolyte can be a saturated potassium chloride solution, the purpose of which is to provide a long-term stable reference potential benchmark and ensure the accuracy of working electrode potential control. The components of the three-electrode system form a complete closed loop through an electrochemical circuit. The optimization of the working electrode surface state, the stability of the counter electrode current conduction, and the accuracy of the reference electrode potential work together to ensure uniform current distribution and controllable metal ion reduction process during cathode co-deposition, thereby obtaining a dense and strongly adherent catalyst layer.

[0011] Furthermore, the substrate is a 1 cm × 1 cm × 0.25 mm platinum-plated titanium felt.

[0012] Furthermore, this application also proposes that, in step 2), the deposition current for the co-deposition treatment is 5-10 mA and the time is 30-60 min.

[0013] The deposition current refers to the constant current value applied during the cathodic co-deposition process. It can be 5 mA, 7 mA, or 10 mA, etc., to control the ion reduction rate and avoid the agglomeration of precious metal particles caused by excessively high current or incomplete deposition caused by excessively low current. The deposition time can be understood as the duration of the cathodic co-deposition process. It can be 30 min, 45 min, or 60 min, etc., to ensure that the deposition layer obtains a suitable thickness, while avoiding excessive particle growth caused by excessive time or insufficient coverage caused by excessive time.

[0014] Therefore, the scheme in this application ensures that the cathode co-deposition process is carried out under stable and controllable conditions by precisely controlling the deposition current and time parameters of the co-deposition treatment. Defining the deposition current range balances ion migration and reduction rates, preventing the formation of coarse particles from localized over-deposition, while ensuring the continuity and uniformity of the deposited layer; setting a time window optimizes the thickness and structural integrity of the deposited layer. The synergistic effect of these parameters strengthens the bonding force between the catalyst and the substrate, improves the uniformity of noble metal distribution, and provides a high-quality precursor for subsequent defect control and heterostructure formation.

[0015] Furthermore, this application also proposes that, in step 3), the plasma cleaning is performed using a plasma cleaner at 100-300 W for 4-15 minutes, with the chamber pressure set to 20-40 Pa and the Ar flow rate at 2-4 L / min. -1 . The proposed solution ensures moderate plasma energy by controlling the plasma cleaning power within the range of 100-300 W, effectively activating ion vacancy defects on the material surface while avoiding structural damage caused by localized overheating. The processing time is controlled within the range of 4-15 min, guaranteeing uniform defect distribution on the material surface and preventing material degradation caused by excessive defect aggregation. The chamber pressure is maintained at 20-40 Pa, optimizing plasma stability and spatial distribution uniformity. Simultaneously, the argon flow rate is fixed at 2-4 L / min. -1 This maintains the dynamic balance of the gas environment. The precise control of these parameters works together to make the generation process of ion vacancy defects highly controllable, providing an ideal precursor state for subsequent secondary calcination treatment.

[0016] Furthermore, this application also proposes that, in step 4), the iridium-containing compound is selected as IrCl3 powder, and the ratio of IrCl3 powder to water is (5-10) mg: (5-10) mL.

[0017] The selection of IrCl3 powder for iridium-containing compounds refers to the use of iridium trichloride as the iridium source. It can be commercially available high-purity IrCl3 powder. Because IrCl3 has high solubility and chemical stability in aqueous solution, it is not prone to rapid hydrolysis and can form a uniform and transparent solution, thereby ensuring the uniform distribution of iridium ions during the impregnation process.

[0018] Furthermore, this application also proposes that the first calcination treatment, the second calcination treatment, and the third calcination treatment all start from room temperature, increase the temperature to 300°C at a heating rate of 3-5°C min⁻¹, and then hold at that temperature for 1-2 hours.

[0019] Specifically, the solution in this application avoids thermal stress shock and achieves uniform heating by starting the temperature increase from room temperature, preventing localized overheating that could lead to rapid migration and aggregation of noble metal atoms; combined with 3-5 ℃ min -1 The slow heating rate ensures stable heat conduction, effectively suppressing the coarsening of noble metal particles and maintaining their nanoscale dispersion. The temperature setting of 300℃ satisfies the energy requirements for oxide crystal phase formation while preventing excessive migration of noble metals at higher temperatures. The controlled holding time of 1-2 hours allows the material to fully restructure at the target temperature, but the strict limitation of the holding time prevents excessive particle growth. This organic combination of parameters ensures the integrity of the heterostructure and the retention of high-density active sites.

[0020] Furthermore, this application also proposes that, in step 5), the drying is carried out at 50-80 °C.

[0021] Secondly, this application also discloses Ir prepared using the above method. x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalyst.

[0022] Thirdly, this application also discloses Ir x Co 3-x Application of O4 / Ir-Co3O4 heterostructure electrocatalyst in PEMWE water electrolysis. PEMWE is an abbreviation for Proton Exchange Membrane Water Electrolyzer.

[0023] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a method for co-deposition bonding defect regulation in the preparation of Ir. x Co 3-xThe method for creating an O4 / Ir-Co3O4 heterostructure electrocatalyst involves first dissolving an iridium-containing compound and a cobalt-containing compound in water to prepare a precursor solution, i.e., a transparent solution A. This precursor solution is then co-deposited in a three-electrode system using constant current cathode electrodeposition. Next, the sample is calcined to prepare Ir-doped Co3O4 as a metal oxide support. Plasma treatment is then applied to create abundant Co and oxygen ion vacancies on the material surface. Finally, calcination is performed again to eliminate oxygen ion vacancies, thus preparing the Ir-doped Co3O4. x-y Co 3-x-z O4 / Ir-Co3O4 provides the possibility for subsequent anchoring of Ir atoms. The treated sample was then immersed in an IrCl3 solution, the solvent was evaporated, and finally, it underwent a final calcination heat treatment to prepare Ir... x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalyst. This heterostructure catalyst can effectively improve the electronic structure around the Ir active center, enhance the metal-metal oxide support interaction, and inhibit the excessive oxidation of Ir active center atoms, thus greatly improving the activity and stability of the catalyst. Therefore, the method provided by this invention can effectively solve the technical problems of low activity, low quality activity, and poor stability of noble metal-based catalysts in the prior art.

[0024] Ir prepared by the present invention x Co 3-x The O4 / Ir-Co3O4 catalyst exhibits excellent activity and exceptional stability. This acidic OER catalyst can be used in a three-electrode system at 200 mA cm⁻¹. -2 Stable electrolysis at current density for over 800 h, and more importantly, Ir x Co 3-x An O4 / Ir-Co3O4 heterostructure catalyst was used as the anode catalyst, and Pt / C as the cathode catalyst. These were combined with a Nafion 115 proton exchange membrane to form a membrane electrode assembly (MEA). The MEA was then subjected to a PEMWE at 18 mA cm⁻¹. -2 It can maintain a stable current density for more than 3000 hours of water electrolysis, and therefore can be applied to PEMWE water electrolysis. Attached Figure Description

[0025] Figure 1 Ir prepared for this invention x Co 3-x Using O4 / Ir-Co3O4 as the anode catalyst and Pt / C as the cathode catalyst, in PEMWE, at 18 mA cm⁻¹ -2 The current density was subjected to a 3000-hour stability test; Figure 2 For the present invention Ir x Co 3-xA solution diagram of IrCl3 used to evaporate the solvent during the preparation of O4 / Ir-Co3O4 heterostructure electrocatalyst; Figure 3 This is a physical image of the acidic OER electrocatalyst of the present invention; Figure 4 For the present invention Ir x Co 3-x Scanning electron microscope image of O4 / Ir-Co3O4 heterostructure electrocatalyst; Figure 5 For the present invention Ir x Co 3-x The distribution images of Ir, Co, and O elements in EDS corresponding to the scanning electron microscope images of the O4 / Ir-Co3O4 heterostructure electrocatalyst; Figure 6 For the present invention Ir x Co 3-x Transmission electron microscopy image of O4 / Ir-Co3O4 heterostructure electrocatalyst; Figure 7 For the present invention Ir x Co 3-x OER polarization curves corresponding to linear sweep voltammetry for O4 / Ir-Co3O4 heterostructure electrocatalysts; Figure 8 For the present invention Ir x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalyst in a three-electrode system, 200 mA cm⁻¹ -2 Stability testing under current density; Figure 9 For the present invention Ir x Co 3-x Using O4 / Ir-Co3O4 as the anode catalyst and Pt / C as the cathode catalyst, in PEMWE, at 18 mA cm⁻¹ -2 Stability testing based on current density; Figure 10 This is a schematic diagram of the structure of the PEM electrolytic cell used in this invention. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0028] The present invention will now be described in further detail with reference to the accompanying drawings: This invention discloses a method for directly constructing highly active and stable noble metal-based catalysts on a conductive substrate, comprising: mixing IrCl4 and Co(NO3)2 . 6H₂O was dissolved in deionized water to prepare a precursor solution. Ir and Co species were uniformly co-deposited onto an acid-treated platinum-titanium felt using a cathodic co-deposition method, followed by drying. The sample was then calcined in a muffle furnace, followed by plasma treatment to create abundant anion and cation vacancies in the material, and then calcined again in a muffle furnace to eliminate oxygen ion vacancies. Afterward, the treated sample was immersed in an IrCl₃ solution, the solvent was evaporated, and finally, a final heat treatment was performed in a muffle furnace to prepare Ir. x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalyst.

[0029] Specifically, it includes the following steps: A method for preparing Ir by co-deposition and defect control x Co 3-x A method for using an O4 / Ir-Co3O4 heterostructure electrocatalyst, characterized by comprising the following steps: Step 1: Mix IrCl4 and Co(NO3)2 . Dissolve 6H2O in deionized water and ultrasonically stir to form a homogeneous and transparent solution for later use.

[0030] Step 2: The acid-treated platinum-titanium felt is sandwiched between platinum sheet electrode holders as the working electrode, the carbon rod as the counter electrode, and the silver / silver chloride electrode as the reference electrode. The solution prepared in Step 1 is used as the electrolyte for cathode co-deposition, followed by drying and preparation for later use.

[0031] Step 3: Place the sample prepared in Step 2 into a muffle furnace for calcination, and set aside for later use.

[0032] Step 4: Place the sample prepared in Step 3 into a Plasma (plasma cleaner) for processing to create ion vacancy defects.

[0033] Step 5: Place the sample prepared in Step 4 in a muffle furnace for calcination to eliminate oxygen ion vacancies, and set aside for later use.

[0034] Step 6: Dissolve IrCl3 in deionized water and sonicate to form a homogeneous and transparent solution for later use.

[0035] Step 7: Immerse the prepared sample in the solution prepared in step 6 and place it in an oven to evaporate the solvent.

[0036] Step 8: Place the sample prepared in Step 7 into a muffle furnace for calcination to prepare the target sample, i.e., Ir. x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalyst.

[0037] Specific implementation examples are as follows: Example 1 1) Ir and Co species were uniformly deposited on acid-treated platinum-titanium felt by co-deposition method, and Ir-Co3O4 was prepared by calcination for use; Specifically, weigh out 16 mg of IrCl4 powder and 1.5 g of Co(NO3)2. . 6H₂O powder was dissolved in 60 mL of deionized water and sonicated at room temperature for 10 min to form a homogeneous and transparent mixed co-deposition precursor solution. Next, a 1 cm × 1 cm × 0.25 mm platinum-plated titanium felt was immersed in a 1:3 HNO₃:H₂SO₄ solution for 5 min, then sonicated in deionized water for 15 min and dried. This was then used as the working electrode, with a carbon rod as the counter electrode and an Ag / AgCl electrode as the reference electrode. The electrolyte was the solution prepared in step 1), the current was 8 mA, and the time was 40 min. The platinum-plated titanium felt was then removed and dried at room temperature for 1 h. The dried sample was then calcined in a muffle furnace at 300 ℃ with a heating / cooling rate of 3 ℃ / min. -1 The calcination time is 1 hour.

[0038] 2) Using the Ir-Co3O4 obtained in step 1) as a substrate, surface defects are constructed using Plasma, and surface oxygen ion vacancies are eliminated by calcination for use. Specifically, the Ir-Co3O4 obtained in step 1) was used as a substrate and placed in a Plasma (plasma cleaner) with a power of 200 W, a vacuum of 30 Pa, and an Ar flow rate of 3 L / min. -1The front and back sides of the sample were treated for 8 min each. The plasma-treated sample was then placed in a muffle furnace and calcined at 200 °C for 1 h, with a heating / cooling rate of 3 °C / min. The sample was removed after complete cooling.

[0039] 3) Prepare a 2 mM IrCl3 solution as a solution for impregnating Ir-Co3O4, and then prepare Ir by calcination. x Co 3-x O4 / Ir-Co3O4 heterostructure target sample catalyst; Specifically, 8 mg of IrCl3 powder was weighed and dissolved in 15 mL of deionized water, and the solution was sonicated at room temperature for 10 min to form a homogeneous and transparent solution. The sample treated in step 2) was then immersed in the IrCl3 solution and placed in an oven at 60 ℃ to evaporate the solvent. Subsequently, the sample was placed in a muffle furnace and calcined at 200 ℃ for 1 h, with a heating and cooling rate of 3 ℃ / min. After complete cooling, the target sample was removed.

[0040] Example 2 1) Ir and Co species were uniformly deposited on acid-treated platinum-titanium felt by co-deposition method, and Ir-Co3O4 was prepared by calcination for use; Specifically, weigh out 15 mg of IrCl4 powder and 1.8 g of Co(NO3)2. . 6H₂O powder was dissolved in 60 mL of deionized water and sonicated at room temperature for 10 min to form a homogeneous and transparent mixed co-deposition precursor solution. Next, a 1 cm × 1 cm × 0.25 mm platinum-titanium plating felt was immersed in a 1:3 HNO₃:H₂SO₄ solution for 5 min, then sonicated in deionized water for 15 min and dried. This felt was then used as the working electrode, with a carbon rod as the counter electrode and an Ag / AgCl electrode as the reference electrode. The electrolyte was the solution prepared in step 1), the current was 10 mA, and the time was 50 min. The platinum-titanium plating felt was then removed and dried at room temperature for 1 h. The dried sample was then placed in a muffle furnace and calcined at 250 °C for 1 h, with heating and cooling rates of 4 °C / min. After complete cooling, the target sample was removed.

[0041] 2) Using the Ir-Co3O4 obtained in step 1) as a substrate, surface defects are constructed using Plasma, and surface oxygen ion vacancies are eliminated by calcination for use. Specifically, the Ir-Co3O4 obtained in step 1) was used as a substrate and placed in a Plasma (plasma cleaner) with a power of 250 W, a vacuum of 40 Pa, and an Ar flow rate of 4 L / min. -1The sample was treated on both sides for 8 min each. The plasma-treated sample was then placed in a muffle furnace and calcined at 250 °C for 1 h, with heating and cooling rates of 4 °C / min. The sample was removed after complete cooling.

[0042] 3) Prepare a 2 mM IrCl3 solution as a solution for impregnating Ir-Co3O4, and then prepare Ir by calcination. x Co 3-x O4 / Ir-Co3O4 heterostructure target sample catalyst; Specifically, 9 mg of IrCl3 powder was weighed and dissolved in 16 mL of deionized water. The solution was ultrasonicated at room temperature for 10 min to form a homogeneous and transparent solution. The sample treated in step 2) was then immersed in the IrCl3 solution and placed in a 60 °C oven to evaporate the solvent. Subsequently, the sample was placed in a muffle furnace and calcined at 250 °C for 1 h, with a heating and cooling rate of 4 °C / min. After complete cooling, the target sample was removed.

[0043] See Figure 1 For the present invention Ir x Co 3-x Using O4 / Ir-Co3O4 as the anode catalyst and Pt / C as the cathode catalyst, in PEMWE, at 18 mA cm⁻¹ -2 Stability tests conducted at current density for 3000 h demonstrated good stability in the electrolyzer.

[0044] See Figure 2 Prepare a 2 mM IrCl3 solution, place it in a custom container, and evaporate the solvent.

[0045] See Figure 3 , for the prepared Ir x Co 3-x Physical image of the O4 / Ir-Co3O4 heterostructure.

[0046] See Figure 4 and Figure 5 , for the prepared Ir x Co 3-x Scanning electron microscope (SEM) images of the O4 / Ir-Co3O4 heterostructure and corresponding EDS distribution images of Ir, Co, and O elements can be seen from the images. x Co 3-x The O4 / Ir-Co3O4 heterostructure exists as uniformly distributed sheet-like nanoflowers, and it can be seen that elements such as Ir, Co, and O are uniformly distributed on the nanosheets.

[0047] See Figure 6 , for the prepared Ir xCo 3-x Lorentz transmission electron microscopy (TEM) image of the O4 / Ir-Co3O4 heterostructure.

[0048] See Figure 7 and Figure 8 Ir x Co 3-x The OER polarization curves of the O4 / Ir-Co3O4 heterostructure electrocatalyst obtained by linear sweep voltammetry and in a three-electrode system at 200 mA cm⁻¹ -2 The stability test at current density, as shown in the figure, indicates that the prepared Ir x Co 3-x The O4 / Ir-Co3O4 heterostructure electrocatalyst exhibits excellent activity and stability under a three-electrode system.

[0049] See Figure 9 and Figure 10 For the present invention Ir x Co 3-x Using O4 / Ir-Co3O4 as the anode catalyst and Pt / C as the cathode catalyst, in PEMWE, at 18 mA cm⁻¹ -2 The stability test was conducted using the current density, and a schematic diagram of the structure of the PEM electrolyzer used in this invention was also shown.

[0050] In summary, this application provides a method for co-deposition bonding defect control in the preparation of Ir. x Co 3-x Methods for O4 / Ir-Co3O4 heterostructure electrocatalysts, Ir x Co 3-x The O4 / Ir-Co3O4 heterostructure electrocatalyst and its application in PEMWE water electrolysis: The catalyst layer is directly formed on the substrate through cathode co-deposition technology, avoiding the weak bonding problem caused by traditional physical coating. At the same time, the catalyst structure is optimized by combining plasma cleaning and calcination defect control processes, which effectively solves the problems of precious metal agglomeration and shedding. It has improved the utilization rate of precious metal atoms, enhanced the bonding force between the catalyst and the substrate, and effectively inhibited the shedding of the catalyst in acidic environment, thereby improving the activity and stability of the electrocatalytic oxygen evolution reaction.

[0051] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for preparing Ir by controlling co-deposition bonding defects x Co 3-x The method for using an O4 / Ir-Co3O4 heterostructure electrocatalyst is characterized by... Includes the following steps: 1) Dissolve the iridium-containing compound and the cobalt-containing compound in water, mix thoroughly, and prepare a transparent solution A; 2) Using the transparent solution A obtained in step 1) as the electrolyte, a cathode co-deposition treatment was performed in a three-electrode system, followed by drying to obtain sample A; 3) Sample A was calcined once, then plasma-cleaned to create ion vacancy defects, and then calcined a second time to eliminate oxygen ion vacancies, thus obtaining sample B. 4) Dissolve the iridium-containing compound in water, mix thoroughly, and prepare a transparent solution B; 5) Immerse sample B obtained in step 3) in transparent solution B, then dry to remove the solvent, and then perform three calcination treatments to obtain Ir. x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalyst.

2. The method for preparing Ir by co-deposition bonding defect control according to claim 1 x Co 3-x The method for using an O4 / Ir-Co3O4 heterostructure electrocatalyst is characterized by... In step 1), the iridium-containing compound is IrCl4 powder, and the cobalt-containing compound is Co(NO3)2. . 6H2O powder; IrCl4 powder, Co(NO3)2 . The ratio of 6H2O powder to water is (20-40) mg : (1-2) g : (30-50) mL; in step 1), thorough mixing is achieved by stirring under ultrasonic conditions for 10-20 min.

3. The method for preparing Ir by controlling co-deposition bonding defects according to claim 1 x Co 3-x The method for using an O4 / Ir-Co3O4 heterostructure electrocatalyst is characterized by... In step 2), the three-electrode system includes: The acid-treated platinum-titanium plating felt is sandwiched between platinum sheet electrode clips to serve as the working electrode. A carbon rod is used as the counter electrode. A silver / silver chloride electrode is used as a reference electrode.

4. The method for preparing Ir by co-deposition bonding defect control according to claim 1 x Co 3-x The method for using an O4 / Ir-Co3O4 heterostructure electrocatalyst is characterized by... In step 2), the deposition current for co-deposition treatment is 5-10 mA, and the time is 30-60 min.

5. The method for preparing Ir by co-deposition bonding defect control according to claim 1 x Co 3-x The method for using an O4 / Ir-Co3O4 heterostructure electrocatalyst is characterized by... In step 3), plasma cleaning is performed at 100-300 W for 4-15 min, with the chamber pressure set at 20-40 Pa and the Ar flow rate at 2-4 L / min. -1 .

6. The method for preparing Ir by co-deposition bonding defect control according to claim 1 x Co 3-x The method for using an O4 / Ir-Co3O4 heterostructure electrocatalyst is characterized by... In step 4), the iridium-containing compound is selected as IrCl3 powder, and the ratio of IrCl3 powder to water is (5-10) mg: (5-10) mL.

7. The preparation of Ir by co-deposition bonding defect control according to claim 1 x Co 3-x The method for using an O4 / Ir-Co3O4 heterostructure electrocatalyst is characterized by... The first, second, and third calcination treatments all started at room temperature and were carried out at 3-5 °C for 3 min. -1 The temperature is increased to 300℃ at a certain rate, and then held at that temperature for 1-2 hours.

8. The preparation of Ir by co-deposition bonding defect control according to claim 1 x Co 3-x The method for using an O4 / Ir-Co3O4 heterostructure electrocatalyst is characterized by... In step 5), drying is carried out at 50-80 ℃.

9. Preparation of Ir using the co-deposition bonding defect control method according to any one of claims 1-8 x Co 3-x Ir was prepared by a method using O4 / Ir-Co3O4 heterostructure electrocatalyst. x Co 3-x O4 / Ir-Co3O4 heterostructure electrocatalyst.

10. The Ir as described in claim 9 x Co 3-x Application of O4 / Ir-Co3O4 heterostructure electrocatalyst in PEMWE water electrolysis.

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