A method for preparing a zr-doped ru-based oxide anode catalyst for efficient and durable acidic water electrolysis

Abstract

The application relates to a preparation method of a Zr-doped RuO2 acidic water electrolysis anode catalyst, which can be realized only by means of room-temperature stirring and subsequent low-temperature annealing, that is, first, metal precursors are fully dissolved under stirring, then the solvent is evaporated in a vacuum drying box and the solid powder is centrifugally washed for several times, finally, the dried solid powder is placed in a muffle furnace for annealing, the crucible is taken out and naturally cooled, and the Zr-doped RuO2 acidic water electrolysis anode catalyst can be obtained. Compared with the existing preparation method, the preparation method provided by the application is simple and easy to implement, the reaction condition is mild, the preparation method is easy to control and has high repeatability, is suitable for large-scale production, and solves the technical problems of high cost of the electrolytic water catalyst, complex process flow and difficulty in batch synthesis in the prior art; the prepared catalyst exhibits significantly enhanced catalytic activity and stability as an anode material in acidic water electrolysis, is superior to self-prepared RuO2 and commercial RuO2, exhibits good application potential in large-scale water electrolysis, and has high industrial research prospect.

Description

Technical Field

[0001] This invention belongs to the field of catalyst and its preparation technology, specifically relating to a method for preparing a Zr-doped RuO2 anode catalyst that can be used for efficient and persistent acidic water electrolysis. Background Technology

[0002] Water electrolysis is a promising method for producing hydrogen, converting sustainable energy-driven electrical energy into chemical energy stored in hydrogen bonds. Compared to traditional alkaline electrolyzers, proton exchange membrane electrolyzers (PEMWEs) offer lower operating temperatures, higher voltage efficiency, higher current density, and better compatibility, making them a promising green hydrogen production technology. However, the slow kinetics of the oxygen evolution reaction (OER) at the anolyte, which typically requires excessive energy consumption, severely limits the efficiency of PEMWEs. Currently, although various catalysts have been developed, iridium oxide (IrO2) remains considered the most advanced anolyte catalyst due to its ability to withstand highly oxidizing and corrosive conditions. However, its high cost and low-quality activity significantly hinder its large-scale application. Recently, ruthenium oxide (RuO2) has been considered a promising alternative to IrO2 in acidic OERs due to its high intrinsic activity and low price. Increasing the initial oxidation state of Ru in RuO2 to promote Ru-centered active oxidation is known to be an effective strategy for improving the performance of electrocatalytic OERs. For example, Qiao et al. prepared a rutile RuO2 (Re 0.06 Ru 0.94 O2) electrocatalysts, in which Re dopants can gain electrons from Ru sites at the onset potential to activate the OER, thereby significantly enhancing OER activity (Jin, H.; Liu, X.; An, P.; Tang, C.; Yu, H.; Zhang, Q.; Peng, H.; Gu, L.; Zheng, Y.; Song, T.; Davey, K.; Paik, U.; Dong, J.; Qiao, S.;. Nat. Commun. 2023, 14, 354.). Luo et al. reported a Bi-RuO2 nanocatalyst, in which the introduction of Bi increases the Bi content. 0.15 Ru 0.85The initial valence state of Ru in O2 promotes the activation of Ru active sites and enhances the reaction kinetics of acidic OER (Wu, L.; Liang, Q.; Zhao, J.; Zhu, J.; Jia, H.; Zhang, W.; Cai, P.; Luo, W.; Chinese. J. Catal. 2023, 55, 182-190.). However, during OER, Ru sites are easily over-oxidized at high potentials to form soluble RuO4. 2- The presence of Ru species often leads to the collapse of the crystal structure and the dissolution of Ru species, resulting in poor stability of RuO2 in acidic OERs. Therefore, developing an effective strategy to balance the relationship between the stability and activity of RuO2-based catalysts is crucial, but challenging, for the practical application of PEMWE. Summary of the Invention

[0003] The purpose of this invention is to solve the technical problems of existing RuO2 acidic OER electrocatalysts, such as complex preparation process, lack of large-scale application potential, low intrinsic activity, easy degradation during operation, and difficulty in using them as anode catalysts in PEM electrolyzers. This invention provides a general preparation method for Zr-doped Ru-based oxide catalysts and demonstrates the good application potential of this material as an anode catalyst for acidic water electrolysis.

[0004] Modulating the electronic structure of Ru-based catalysts is a common strategy to improve their activity and stability. Metal doping can effectively alter the electronic structure of catalysts by changing the coordination environment of active sites, introducing defects, and adjusting the Ru valence state to promote Ru active centers, thereby improving the poor stability of Ru-based catalysts and enhancing their OER activity. Experimental results show that Zr doping can significantly reduce the acidic OER overpotential and prolong the stable operating time of RuO2-based catalysts.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for preparing a Zr-doped Ru-based oxide (RuO2) anode catalyst for efficient and persistent acidic water electrolysis, using a room-temperature stirring method, includes the following steps: Step 1: Disperse the Ru metal source in deionized water and stir at room temperature for a period of time to mix it evenly to obtain a Ru precursor solution; Step 2: Add Zr metal source to the Ru precursor solution synthesized in Step 1, keeping the molar ratio of Zr metal source to Ru metal source at 0.05:1-0.2:1, and then stir at room temperature to obtain a homogeneous Ru-Zr precursor solution; Step 3: Place the Ru-Zr precursor solution in a vacuum drying oven and dry for several hours to obtain a black solid powder; Step 4: After washing the obtained black solid powder by centrifugation with deionized water, dry it in a vacuum drying oven and collect the solid powder. Step 5: Place the solid powder obtained in step 4 into a muffle furnace and calcine it at high temperature, then let it cool naturally to room temperature to obtain the doped Ru-based oxide Zr-RuO2.

[0006] Preferably, in step 1, the Ru metal source is RuCl3 and C. 15 H 21 O6Ru, stirring at room temperature for 5-10 minutes.

[0007] Preferably, in step 2, the Zr metal source is ZrCl4 and Zr(NO3)4, the molar ratio of Zr metal source to Ru metal source is 0.05:1-0.2:1, and the stirring time at room temperature is 5-10 min.

[0008] Preferably, in step 3, the vacuum drying temperature is 60-80 ℃ and the drying time is 4-6 h.

[0009] Preferably, in step 4, the deionized water is used for centrifugal washing 4-6 times at a speed of 8000-13000 rpm for 1-5 minutes.

[0010] Preferably, in step 4, the vacuum drying temperature is 60-80 ℃ and the drying time is 2-3 h.

[0011] Preferably, in step 5, the calcination temperature is 270-400 ℃ and the holding time is 1-3 h.

[0012] Preferably, in steps 1 and 4, the resistivity of the deionized water used is 18.2-18.25 MΩ·cm. Advantages and beneficial effects of the present invention: Compared with existing technologies, the method of this invention uses widely available raw materials, requires mild reaction conditions, has high reproducibility, and is suitable for large-scale production. This invention provides a Zr-RuO2 material with a rutile crystal structure, exhibiting significantly enhanced catalytic activity and stability in acidic water electrolysis, superior to both homemade RuO2 and commercial RuO2. During stirring at room temperature, the Ru in RuO2... 4+ Zr diffuses from the crystal structure into the solution. 4+Metal doping is achieved by diffusion into the RuO2 crystal structure. The introduction of Zr increases the initial valence state of Ru in Zr-RuO2, thereby promoting the activation of Ru active sites and improving the reaction kinetics of acidic OER. Furthermore, the presence of Zr enhances electronic interactions to maintain structural stability. Therefore, this material exhibits good electrocatalytic OER performance under acidic conditions. Simultaneously, a PEM electrolyzer with Zr-RuO2 as the anode at 250 mA cm⁻¹... -2 It can operate stably for more than 140 hours under the operating current, demonstrating good application potential as an anode catalyst for acidic water electrolysis. The preparation method of this invention is simple, easy to implement, and environmentally friendly, with the potential for large-scale industrial production, laying the foundation for the mass production of RuO2-based catalysts. Attached Figure Description

[0013] Figure 1 The XRD patterns of the Zr-RuO2 and RuO2 catalysts prepared in Example 1 of this invention are shown below. Figure 2 The image shows the TEM morphology of the Zr-RuO2 catalyst prepared in Example 1 of this invention. Figure 3 The high-resolution XPS spectrum of the Zr-RuO2 catalyst prepared in Example 1 of this invention; Figure 4 Linear sweep voltammetric curves of the Zr-RuO2 catalyst, RuO2 catalyst, and commercial RuO2 prepared in Example 1 of this invention in 0.5 mol / L sulfuric acid solution; Figure 5 The Zr-RuO2 catalyst prepared in Example 1 of this invention and commercial RuO2 were subjected to a reaction in 0.5 mol / L sulfuric acid solution at 100 mA cm⁻¹. -2 Chronopotential curves at current density; Figure 6 (a) PEM performance test curves and (b) stability test curves of the Zr-RuO2 catalyst prepared for Example 1 of the present invention and commercial RuO2; Figure 7 Zr prepared in Examples 4, 5 and 15 of this invention 0.05 -RuO2 and Zr 0.15 -RuO 2、 Linear sweep voltammetry curve of pure RuO2 sample in 0.5 mol / L sulfuric acid solution. Detailed Implementation

[0014] The preferred embodiments of the present invention will now be described with reference to the accompanying drawings and specific embodiments. It should be noted that the embodiments described below are intended to facilitate the understanding of the present invention and do not constitute any limitation thereof.

[0015] The preparation method of Zr-doped RuO2 nanoparticle acidic water electrolysis anode catalyst is as follows: Step 1: At room temperature, disperse RuCl3 in deionized water and stir for a period of time at room temperature to mix it evenly, thus obtaining a Ru precursor solution; The metal salt can be dissolved by stirring at room temperature for more than 5 minutes; here, 10 minutes was selected after optimization. The preferred amount of RuCl3 is 0.5-1.0 mmol.

[0016] Step 2: At room temperature, add a certain proportion of ZrCl4 to the Ru precursor solution synthesized in Step 1, and then stir at room temperature to obtain a homogeneous Ru-Zr precursor solution. The metal salt can be dissolved by stirring at room temperature for more than 5 minutes; here, 10 minutes was selected after optimization. The preferred amount of Zr metal source (ZrCl4) is 0.05-0.2 mmol.

[0017] Step 3: Place the Ru-Zr precursor solution in a vacuum drying oven and dry for several hours to obtain a black solid powder; The drying temperature can be above 60 ℃. After optimization, 80 ℃ is selected here. The drying time needs to be at least 4 hours; after optimization, 6 hours is selected here.

[0018] Step 4: After washing the obtained black solid powder by centrifugation with deionized water, dry it in a vacuum drying oven and collect the solid powder. The deionized water used for centrifugation has a concentration of 18.25 MΩ·cm. The preferred number of centrifugation washes is 6, with a rotation speed of 8000-13000 rpm and a time of 1-5 min, the purpose of which is to remove unstable substances from the RuO2 surface. A drying temperature above 60 ℃ is acceptable; here, 80 ℃ has been optimized. The drying time requires 2-3 h; here, 2 h has been optimized.

[0019] Step 5: Place the solid powder obtained in Step 4 into a muffle furnace and calcine it at high temperature, then let it cool naturally to room temperature to obtain the doped Ru-based oxide Zr-RuO2; The calcination temperature needs to be above 270 ℃. After optimization, 350 ℃ has been selected. The holding time needs to be at least 1 hour; after optimization, 2 hours has been selected.

[0020] In the following examples, the reaction conditions not specified are the same as those in the preparation method above and will not be repeated. All raw materials used are analytical grade, commercially available conventional chemicals, and do not require further processing. Example

[0021] At room temperature, 1 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve it completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and then calcined in a muffle furnace at 350 °C with a heating rate of 5 °C / min for 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained.

[0022] XRD analysis was performed on the Zr-doped RuO2 catalyst obtained in Example 1, and the results are as follows: Figure 1 As shown, the oxide crystal structure in the obtained catalyst remains intact, with only the peak of the rutile phase RuO2 appearing, indicating that the introduction of Zr did not form a new phase.

[0023] The Zr-doped RuO2 nanoparticle anode catalyst for water electrolysis obtained in Example 1 was characterized by TEM, and the results are as follows: Figure 2 As shown, the obtained catalyst exhibits a three-dimensional cross-linked network structure of nanoparticles, in which the metal is uniformly dispersed in the form of nanoparticles without agglomeration.

[0024] XPS analysis was performed on the Ru 3p spectrum of the Zr-doped RuO2 catalyst obtained in Example 1. The results are as follows: Figure 3 As shown, the high-resolution XPS spectrum of Ru 3p reveals Ru 3p 3 / 2 and Ru 3p 1 / 2 The peaks are located at 463.2 eV and 484.8 eV, respectively, indicating the presence of Ru. 4+ With the incorporation of Zr, Ru 3p in Zr-RuO2 3 / 2 and Ru 3p 1 / 2 The peak position of Ru shifts to a higher binding energy compared to RuO2. This indicates that with Zr incorporation, there are electronic interactions between Ru and surrounding atoms, and Ru... 4+ Acting as an electron donor, while simultaneously increasing the initial oxidation state of Ru, this material is beneficial for improving OER activity and promoting acidic OER kinetics. Furthermore, this dopant-induced electronic interaction has been shown to promote structural stability and enhance electrocatalytic performance by lowering the energy barrier and preventing excessive oxidation of the active material. Therefore, this material holds promise for further improvements in long-term stability of acidic OER compared to commercial RuO2.

[0025] The Zr-doped RuO2 nanoparticle anode catalyst for water electrolysis obtained in Example 1 was subjected to a reaction at 0.5 mol L⁻¹ -1 Linear sweep voltammetry was performed in sulfuric acid solution, and the results are as follows: Figure 4 As shown, the obtained catalyst exhibits superior acidic OER catalytic activity compared to commercial RuO2 catalysts.

[0026] The Zr-doped RuO2 nanoparticle anode catalyst for water electrolysis obtained in Example 1 was subjected to a reaction at 0.5 mol L⁻¹ -1 10 mA cm in sulfuric acid solution -2 Chronopotential testing was performed at current density, and the results are as follows: Figure 5 As shown, the obtained catalyst exhibits superior long-term stability compared to commercial RuO2 catalysts.

[0027] The Zr-doped RuO2 nanoparticle anode catalyst for water electrolysis obtained in Example 1 was subjected to PEMWE electrolysis tests, and the results are as follows: Figure 6 As shown in (a), a PEM electrolyzer with Zr-RuO2 as the anode operates at 500 mA cm⁻¹. -2 The voltage at the current density is 1.74 V, which is 170 mV lower than that of commercial RuO2 anodes (1.91 V). For example... Figure 6 As shown in (b), the PEM electrolyzer with Zr-RuO2 as the anode operates at 250 mA cm⁻¹. -2 It can operate stably for more than 140 hours under the working current with only a slight decrease, demonstrating excellent potential for industrial water electrolysis applications. Example

[0028] At room temperature, 0.5 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and then calcined in a muffle furnace at 350 °C with a heating rate of 5 °C / min for 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 2, and the results were similar to those of Example 1. Example

[0029] At room temperature, 0.75 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at 350 °C with a heating rate of 5 °C / min for 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 3, and the results were similar to those of Example 1. Example

[0030] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.05 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times by centrifugation with deionized water and then placed in a vacuum drying oven and dried at 80 °C for 2 h. The solid powder was collected and then calcined in a muffle furnace at a temperature of 350 °C, a heating rate of 5 °C / min, and a holding time of 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 4, and the results were similar to those of Example 1. Example

[0031] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.15 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at 350 °C with a heating rate of 5 °C / min for 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 5, and the results were similar to those of Example 1. Example

[0032] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at 270 °C with a heating rate of 5 °C / min for 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization of the Zr-doped RuO2 water electrolysis anode catalyst in Example 6 were performed, and the results were similar to those in Example 1. Example

[0033] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at 300 °C with a heating rate of 5 °C / min for 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 7, and the results were similar to those of Example 1. Example

[0034] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at 380 °C with a heating rate of 5 °C / min for 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization of the Zr-doped RuO2 water electrolysis anode catalyst in Example 8 were performed, and the results were similar to those in Example 1. Example

[0035] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at a temperature of 400 °C, a heating rate of 5 °C / min, and a holding time of 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 9, and the results were similar to those of Example 1. Example

[0036] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at 350 °C with a heating rate of 5 °C / min for 1 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 10, and the results were similar to those of Example 1. Example

[0037] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times by centrifugation with deionized water and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at 350 °C with a heating rate of 5 °C / min for 3 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 11, and the results were similar to those of Example 1. Example

[0038] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at 350 °C with a heating rate of 10 °C / min for 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 12, and the results were similar to those of Example 1. Example

[0039] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol ZrCl4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and then calcined in a tube furnace at a temperature of 350 °C, a heating rate of 5 °C / min, and a holding time of 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 13, and the results were similar to those of Example 1. Example

[0040] At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve completely. Then, 0.1 mmol Zr(NO3)4 was added to the resulting solution, and the mixture was stirred for 10 min at room temperature to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times by centrifugation with deionized water and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at 350 °C with a heating rate of 5 °C / min for 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 14, and the results were similar to those of Example 1. Example

[0041] At room temperature, 1.0 mmol C 15 H 21O6Ru was added to 40 mL of deionized water and stirred for 10 min to ensure complete dissolution. Then, 0.1 mmol of ZrCl4 was added to the resulting solution, followed by stirring at room temperature for 10 min to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times by centrifugation with deionized water and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and then calcined in a muffle furnace at a temperature of 350 °C, a heating rate of 5 °C / min, and a holding time of 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 15, and the results were similar to those of Example 1. Example

[0042] At room temperature, 1.0 mmol C 15 H 21 O6Ru was added to 40 mL of deionized water and stirred for 10 min to ensure complete dissolution. Then, 0.1 mmol of Zr(NO3)4 was added to the resulting solution, followed by stirring at room temperature for 10 min to obtain a homogeneous Ru-Zr precursor solution. This solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times with deionized water by centrifugation and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and then calcined in a muffle furnace at a temperature of 350 °C, a heating rate of 5 °C / min, and a holding time of 2 h. After natural cooling to room temperature, Zr-doped RuO2 was obtained. XRD analysis and TEM morphology characterization analysis were performed on the Zr-doped RuO2 water electrolysis anode catalyst of Example 16, and the results were similar to those of Example 1.

[0043] Comparative Example 1 At room temperature, 1.0 mmol RuCl3 was added to 40 mL of deionized water and stirred for 10 min to dissolve it completely. The solution was then placed in a vacuum drying oven and dried at 80 °C for 6 h to obtain a black solid powder. The obtained solid powder was washed six times by centrifugation with deionized water and then dried in a vacuum drying oven at 80 °C for 2 h. The solid powder was collected and calcined in a muffle furnace at a temperature of 350 °C, a heating rate of 5 °C / min, and a holding time of 2 h. After natural cooling to room temperature, a pure phase Ru-based oxide (RuO2) without metal doping was obtained. XRD analysis was performed on the self-made RuO2 catalyst of Comparative Example 1, and the results are as follows: Figure 1 As shown, the resulting oxide crystal structure exhibits the peaks of the standard rutile phase RuO2.

[0044] XPS analysis was performed on the Ru 3p spectrum of the self-made RuO2 catalyst in Comparative Example 1, and the results are as follows: Figure 3 As shown, Ru 3p in the high-resolution XPS spectrum of Ru 3p 3 / 2 and Ru 3p 1 / 2 The peak position of the peak is lower than that of Zr-RuO2, indicating that the incorporation of Zr leads to electronic interactions between Ru and surrounding atoms.

[0045] The self-made RuO2 catalyst obtained in Comparative Example 1 was tested at 0.5 mol L⁻¹. -1 Linear sweep voltammetry was performed in sulfuric acid solution, and the results are as follows: Figure 4 As shown, the obtained catalyst was at 10 mA cm⁻¹ -2 The overpotential at the current density is close to 300 mV, and the activity is significantly lower than that of Zr-RuO2, indicating that Zr doping has an enhancing effect on the OER activity of RuO2 catalyst.

[0046] Since changes in parameters such as the amount of RuCl3 introduced (Examples 2-3), calcination temperature (Examples 6-9), calcination holding time (Examples 10-11), calcination heating rate (Example 12), calcination apparatus (Example 13), and metal source (Examples 14-16) did not lead to significant differences in the acidic OER electrocatalytic performance of the prepared RuO2 catalyst, but after the RuCl3 addition was quantitative, changes in the ZrCl4 doping amount (Examples 1 and 4-5) led to significant differences in the acidic OER electrocatalytic performance of the RuO2-based catalyst. Therefore, the Zr-doped RuO2 water electrolysis anode catalysts described in Examples 1 and 4-5 are not considered suitable for research and application as acidic OER electrocatalysts. Figure 4 and Figure 7 As shown, at 10 mA cm -2 At the given current density, the acidic OER overpotential of the Zr-doped RuO2 catalysts obtained in Examples 1 and 4-5 was generally between 220 and 270 mV. This indicates that although the catalytic performance of RuO2 with different Zr doping amounts decreased, the overall catalytic activity was still significantly improved compared to commercial RuO2. Therefore, other batches of Zr-RuO2 prepared by this method also have the potential for acidic OER applications.

[0047] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention. Any obvious changes or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A method for preparing a Zr-doped RuO2 anode catalyst for efficient and persistent acidic water electrolysis, characterized in that, The preparation steps include the following: Step 1, Synthesis of Ru precursor solution: Disperse the Ru metal source in deionized water and stir at room temperature to mix it evenly to obtain the Ru precursor solution; Step 2: Add Zr metal source to the Ru precursor solution synthesized in Step 1. The molar ratio of Zr metal source to Ru metal source is 0.05:1 - 0.2:

1. Then stir at room temperature to obtain a homogeneous Ru-Zr precursor solution. Step 3: Place the Ru-Zr precursor solution in a vacuum drying oven and dry it at a temperature of 60-80 ℃ to obtain a black solid powder; Step 4: After washing the obtained black solid powder by centrifugation with deionized water, place it in a vacuum drying oven at a temperature of 60-80 ℃ and collect the solid powder. Step 5: Place the solid powder obtained in step 4 into a muffle furnace and calcine it at a high temperature of 270-400℃. Then, let it cool naturally to room temperature to obtain a Zr-doped RuO2 anode catalyst. The obtained catalyst exhibits a three-dimensional nanoparticle cross-linked network structure.

2. The method according to claim 1, characterized in that, In step 1, the Ru metal source is RuCl3.

3. The method according to claim 1, characterized in that, In step 1, the resistivity of the deionized water used is 18.2-18.25 MΩ·cm; the stirring time at room temperature is 5-10 min.

4. The method according to claim 1, characterized in that, In step 2, the Zr metal source is ZrCl4 or Zr(NO3)4, and the stirring time at room temperature is 5-10 min.

5. The method according to claim 1, characterized in that, The drying time in step 3 is 4-6 hours.

6. The method according to claim 1, characterized in that, In step 4, the number of centrifugal washing cycles is 4-6, the rotation speed is 8000-13000 rpm, and the time is 1-5 min; the drying time is 2-3 h.

7. The method according to claim 1, characterized in that, In step 5, the heat preservation time is 1-3 hours.

8. The application of Zr-doped RuO2 prepared by the method of any one of claims 1-7 as an acidic water electrolysis catalyst.

9. The application according to claim 8, characterized in that, At 10 mAcm -2 At a given current density, the overpotential of the Zr-doped RuO2 in the acidic oxygen evolution reaction is between 220 and 300 mV.

10. The application according to claim 8, characterized in that, A proton exchange membrane electrolyzer with Zr-doped RuO2 as the anode was used at 250 mA cm⁻¹ -2 It can operate stably for more than 140 hours under the operating current.

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