A boron and metal co-doped modified ruthenium oxide anode catalyst, a preparation method and application thereof

Abstract

The application provides a boron and metal double-doped modified ruthenium oxide anode catalyst, a preparation method and application thereof, and belongs to the technical field of new energy materials and electrochemical catalysis. First, urea and glucose are dissolved in deionized water as a structure directing agent, and then boric acid, ruthenium chloride and hydrated gallium nitrate are added; the mixture is stirred at room temperature until dissolved; a gel solid precursor is obtained by using a hydrothermal method; after washing treatment and vacuum drying, the precursor is subjected to heat treatment in an atmosphere to obtain a boron and metal double-doped ruthenium oxide electrocatalyst. The synthesis process is simple and easy to implement; the boron and metal doping modification not only reduces the loading amount of the noble metal ruthenium, but also improves the activity and stability of the catalyst, thereby providing a good idea for double-element doped ruthenium oxide and having industrial application potential.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of new energy materials and electrochemical catalysis, and particularly relates to a boron and metal double-doped modified ruthenium oxide anode catalyst, a preparation method and application thereof. BACKGROUND

[0002] With the development of economy and society, the consumption of non-renewable energy such as coal, oil and natural gas has seriously led to problems such as environmental damage, air pollution and greenhouse effect. When these problems come one after another, people begin to increase the demand for green and sustainable energy such as wind energy, tidal energy and solar energy. But as we all know, these energies are currently intermittent energies, which often cannot be reasonably transported and stored for use, causing a certain waste. Hydrogen energy can be used as an energy carrier for these intermittent energies, which has high energy density and is clean and pollution-free, and is currently one of the most popular secondary energies. By converting these intermittent electric energy into hydrogen energy through water electrolysis, it is crucial to establish a hydrogen society. Using proton exchange membrane to electrolyze water to produce hydrogen can well solve many problems existing in alkaline water splitting, such as low hydrogen production efficiency, low upper limit of current density and high impedance. However, due to the strong acidity and strong oxidizing characteristics of the electrolytic environment of acidic water splitting, the acidic oxygen evolution reaction (OER) faces great challenges in stability.

[0003] Currently, the Ir-based catalyst with high stability and performance is commonly used in industrial water electrolysis, but the price of Ir catalyst is relatively high and the overpotential is relatively high. The current overpotential at 10 mAcm -2 -250mV and above (Ailong Li, et al. Atomically dispersed hexavalent iridium oxide from MnO2 reduction for oxygen evolution catalysis [J]. Science, 2024, 384(5193): 666-670). At this time, the relatively low-cost and low-overpotential Ru-based catalyst is attracting more and more attention. However, the stability problem of Ru-based catalysts has been plaguing researchers, and the problem of how to handle the relationship between stability and voltage needs to be solved. Ru cations are easily oxidized in the acidic environment during the OER process to produce soluble substances, which causes the collapse of the crystal structure of the catalyst, which greatly limits its service life in practical applications. Researchers have tried various strategies, including metal doping, strain effect, surface reconstruction, morphology control and electronic structure adjustment, to improve the activity and durability of Ru-based electrocatalysts. Although some progress has been made, most Ru-based catalysts have an overpotential of 10 mAcm -2only a few hours, far from meeting the needs of commercial applications. Liu Jingjun (Jingjun Liu, et al. Oxygen vacancy-electron polarons featured InSnRuOz oxides: orderly and concerted In-Ov-Ru-O-Sn substructures for acidic water oxidation[J]. Advanced Materials, 2024, 36(52): 2414579) team first synthesized InSnRuO2controlling the density of oxygen defects (O v ) by isomorphic substitution strategy, the overpotential of the catalyst is 183mV at 10mAcm -2 , and it can be stably operated for 200h. However, the problems of low catalytic activity and poor sustained stability in acidic environment have not been completely solved, making it difficult to meet the strong acid resistance and high activity under industrial conditions. Therefore, it is of great practical significance to develop Ru-based OER catalysts that can work stably in acidic environment for a long time. SUMMARY

[0004] In order to break free from the shackles of the above-mentioned prior art and solve the problems of poor stability and high overpotential of the anode catalyst in current acidic OER, the present application proposes a boron and metal double-doped modified ruthenium oxide anode catalyst, its preparation method and application, which can be directly applied to electrocatalytic oxygen evolution reaction in acidic environment and exhibit excellent activity and stability.

[0005] The application adopts the following technical solutions:

[0006] A boron and metal double-doped modified ruthenium oxide anode catalyst, the anode catalyst has a morphology of close nanospheres, the size of the nanospheres is 40-60nm, and the molar ratio of boron, doped metal and ruthenium is (3-3.3):(3-0.2):1.

[0007] A preparation method of a boron and metal double-doped modified ruthenium oxide anode catalyst, the preparation method comprises the following steps:

[0008] Step 1: weigh a certain amount of glucose and urea, dissolve them in deionized water, stir until completely dissolved, and obtain a mixed solution A.

[0009] Step 2: weigh a certain amount of ruthenium chloride, nitrate hydrate and boric acid, dissolve them in deionized water, stir until completely dissolved, and obtain a mixed solution B.

[0010] Step 3, mix the mixed solution A with the mixed solution B, stir until dissolved to obtain a precursor mixed solution C.

[0011] Step 4, place the precursor solution C in a hydrothermal kettle, and perform a hydrothermal operation in an oven, and after washing, obtain a gel solid precursor.

[0012] Step 5, dry the obtained gel solid precursor in a vacuum drying box, and grind the obtained solid product into a powder.

[0013] Step 6, sinter the powder in a tube furnace with air as the gas atmosphere to form a black powder, and cool to room temperature to obtain a boron and metal double-doped modified ruthenium oxide anode catalyst.

[0014] Further, in step 1, the concentrations of glucose and urea in the mixed solution A are 0.4-1 mol / L and 0.1-0.6 mol / L, respectively.

[0015] Further, in step 2, the concentrations of ruthenium chloride, nitrate hydrate, and boric acid in the mixed solution B are 0.05-0.1 mol / L, 0.02-0.15 mol / L, and 0.15-0.33 mol / L, respectively, wherein the nitrate hydrate is gallium nitrate hydrate, indium nitrate hydrate, or aluminum nitrate hydrate, and is preferably gallium nitrate hydrate, and the concentration of gallium nitrate hydrate is preferably 0.05-0.1 mol / L.

[0016] Further, in step 3, the volume ratio of the mixed solution A to the mixed solution B is 1:1-2:1.

[0017] Further, in step 4, the hydrothermal temperature is 100-180℃, the hydrothermal time is 6-12h, and after hydrothermal treatment, the gel is washed with anhydrous ethanol and deionized water in a centrifuge for 3-5 times until the upper liquid is clear and transparent.

[0018] Further, in step 5, the drying time is 6-18h, and the drying temperature is 50-70℃.

[0019] Further, in step 6, the sintering process is as follows: heat to 400-500℃ at a heating rate of 2-5℃ / min, and keep the temperature for 8-16h.

[0020] An application of a boron and metal double-doped modified ruthenium oxide anode catalyst is used in the electrolysis of water to produce hydrogen. The specific process of electrolysis of water to produce hydrogen is as follows: using the prepared anode catalyst as the working electrode, an Ag / AgCl electrode as the reference electrode, and a carbon rod as the counter electrode, performing an acid electrolysis water oxygen evolution reaction in an oxygen-saturated 0.5 mol / L sulfuric acid solution.

[0021] The innovation of the present application is that: the present application promotes the synergistic effect between the doped metal elements and ruthenium Ru by introducing boron B. On the one hand, the introduction of boron reduces the crystal structure of the catalyst. Compared with the crystalline structure, the amorphous structure can not only provide significant active sites, but also can actively adjust the Ru-O bond and optimize the oxygen intermediate adsorption energy, so as to achieve the effect of significantly improving the activity; on the other hand, the electronic space regulation of B optimizes the synergistic effect between the doped metal elements and ruthenium Ru. The common synergistic effect between non-metallic B and the doped metal elements optimizes the catalytic activity of RuO2, and after doping, the dissolution effect of Ru is inhibited, and the acid resistance of RuO2 in the OER process is effectively improved and the stability is improved.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] (1) The synthesis process of the present application is simple and easy to operate, and the boron and metal element co-doped modified ruthenium oxide can be prepared by gel method combined with calcination method. Compared with the existing methods such as molten salt method and electrospinning method, it can be prepared on a large scale and at low cost.

[0024] (2) The boron and metal element co-doped modified ruthenium oxide catalyst prepared by the present application has excellent activity and stability in the acid OER process. The present application solves the problems of poor activity and stability of the ruthenium oxide catalyst by co-doping B and metal elements, so that the overpotential at 10 mAcm -2 of the present application is reduced to about 170 mV, and the stability is improved from 100 hours to more than 1400 hours, greatly improving the catalytic activity and stability of the ruthenium oxide catalyst in acidic medium.

[0025] (3) The iridium-based catalyst commonly used in industrial acidic electrolytic water is expensive, and the present application uses Ru-based catalyst to replace the noble metal iridium, greatly reducing the cost and having more excellent performance. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is the SEM graph of BGa-RuO2 in Example 1.

[0027] Figure 2 It is the element mapping graph of BGa-RuO2 in Example 1.

[0028] Figure 3 It is the XRD diffraction graph of Example 1 (BGa-RuO2), Comparative Example 1 (B-RuO2), Comparative Example 2 (Ga-RuO2), Comparative Example 3 (Home-RuO2) material and standard pdf card comparison graph.

[0029] Figure 4OER polarization curves for Example 1 (BGa-RuO2), Comparative Example 1 (B-RuO2), Comparative Example 2 (Ga-RuO2), Comparative Example 3 (Home-RuO2), and commercial RuO2 (Com-RuO2) materials.

[0030] Figure 5 Stability plot for Example 1 (BGa-RuO2)

[0031] Figure 6 Stability plot for Comparative Example 3 (Home-RuO2) DETAILED DESCRIPTION

[0032] In order to further understand the present application, the technical solutions in the embodiments of the present application are described clearly and completely. Meanwhile, the examples described below are only a part of the present application, not all. The following description is only for further illustrating the advantages and features of the present application, not for limiting the claimed rights of the present application. Other embodiments obtained by the ordinary skilled in the art without making creative efforts are within the scope of protection of the present application.

[0033] The technical solutions of the present application will be further described below in combination with specific examples.

[0034] Example 1

[0035] A boron and gallium double-doped modified ruthenium oxide anode catalyst, the preparation method thereof comprises the following steps:

[0036] (1) Cut the carbon paper into an area of 1 cm x 2 cm, and then hydrothermally treat the cut carbon paper in diluted concentrated nitric acid (HNO3:H2O volume ratio of 1:1) at 150°C for 6h. After taking out, sequentially place in ethanol and water for ultrasonic treatment for 30min, and then dry at 70°C for 6h to obtain a treated conductive carbon paper substrate.

[0037] (2) Weigh 3g of glucose and 0.6g of urea into 10mL of deionized water, and stir to dissolve at room temperature to obtain a mixed solution A.

[0038] (3) Weigh 30mg of ruthenium chloride, 36.8mg of gallium nitrate and 26mg of boric acid into 10mL of deionized water, and stir to dissolve at room temperature to obtain a mixed solution B.

[0039] (4) Mix the mixed solutions A and B uniformly, and stir at room temperature for 30min until completely dissolved. Transfer to a 50mL hydrothermal kettle, set the hydrothermal temperature to 160°C and the hydrothermal time to 8h to obtain a sol solid precursor.

[0040] (5) The sol solid precursor was washed three times by centrifugation with deionized water and anhydrous ethanol respectively. The supernatant was discarded. The sol solid was dried in a vacuum drying oven at 70°C for 12 hours and then ground into powder in a mortar.

[0041] (6) The powder was sintered in a tube furnace with air as the gas atmosphere to form a black powder. The reaction temperature was set at 400℃, the heating rate was 5℃ / min, and the sintering time was 12h to obtain a boron and gallium dual-element doped and modified ruthenium oxide BGa-RuO2 catalyst.

[0042] (7) Take 5 mg of the obtained BGa-RuO2 catalyst, use 460 μL of ethanol as a dispersant and 40 μL of 5 wt% Nafion 117 solution as a binder to drop-coat the BGa-RuO2 catalyst onto the carbon paper pretreated in (1), and dry it in an oven at 60 °C to obtain the BGa-RuO2 electrode.

[0043] (8) The composite electrode prepared above was used for the electrocatalytic oxygen evolution reaction (OER). The specific steps were as follows: a three-electrode system was constructed, in which the working electrode was a BGa-RuO2 electrode, the reference electrode was a silver / silver chloride electrode, and the counter electrode was a carbon rod. The OER performance was tested in an oxygen-saturated 0.5 mol / L sulfuric acid solution. The results showed that BGa-RuO2 only required an overpotential of 170 mV to achieve 10 mA cm⁻¹. -2 It has a current density that can be maintained for more than 1,400 hours without decay.

[0044] Example 2

[0045] A boron and aluminum co-doped ruthenium oxide anode catalyst is prepared by the following steps:

[0046] (1) Cut carbon paper into 1cm×2cm pieces, and then heat the cut carbon paper in diluted concentrated nitric acid (HNO3:H2O volume ratio of 1:1) at 150℃ for 6h. After taking it out, place it in ethanol and water and sonicate for 30min in sequence, and then dry it at 70℃ for 6h to obtain the treated conductive substrate carbon paper.

[0047] (2) Weigh 1.8g of glucose and 0.15g of urea and dissolve them in 15mL of deionized water. Stir at room temperature until dissolved to obtain mixed solution A.

[0048] (3) Weigh 15mg of ruthenium chloride, 20mg of aluminum nitrate and 22mg of boric acid and dissolve them in 10mL of deionized water. Stir at room temperature until dissolved to obtain mixed solution B.

[0049] (4) Mix solutions A and B thoroughly and stir at room temperature for 30 min until completely dissolved. Transfer to a 50 mL hydrothermal reactor, set the hydrothermal temperature to 180 °C and the hydrothermal time to 12 h to obtain the sol-sol precursor.

[0050] (5) The sol-sol precursor was washed four times each with deionized water and anhydrous ethanol. The supernatant was discarded. The sol-sol was dried in a vacuum drying oven at 50°C for 6 hours and then ground into powder in a mortar.

[0051] (6) The powder was sintered in a tube furnace with air as the gas atmosphere to form a black powder. The reaction temperature was set at 450℃, the heating rate was 4℃ / min, and the reaction time was 8h to obtain a boron and aluminum dual-element doped and modified ruthenium oxide BAl-RuO2 catalyst.

[0052] (7) Take 5 mg of the obtained BAl-RuO2 catalyst, use 460 μL of ethanol as a dispersant and 40 μL of 5 wt% Nafion 117 solution as a binder to drop the catalyst onto the carbon paper pretreated in (1), and put it into an oven at 60 °C to dry to obtain the BAl-RuO2 electrode.

[0053] (8) The composite electrode prepared above was used for the electrocatalytic oxygen evolution reaction (OER). The specific steps were as follows: a three-electrode system was constructed, in which the working electrode was a BAl-RuO2 electrode, the reference electrode was a silver / silver chloride electrode, and the counter electrode was a carbon rod. The OER performance was tested in an oxygen-saturated 0.5 mol / L sulfuric acid solution. The results showed that BAl-RuO2 required an overpotential of 179 mV to achieve 10 mA cm⁻¹. -2 It has a current density that can be maintained for more than 300 hours without decay.

[0054] Example 3

[0055] A boron and indium co-doped ruthenium oxide anode catalyst, the preparation method of which includes the following steps:

[0056] (1) Cut carbon paper into 1cm×2cm pieces, and then heat the cut carbon paper in diluted concentrated nitric acid (HNO3:H2O volume ratio of 1:1) at 150℃ for 6h. After taking it out, place it in ethanol and water and sonicate for 30min in sequence, and then dry it at 70℃ for 6h to obtain the treated conductive substrate carbon paper.

[0057] (2) Weigh 4.8g of glucose and 0.6g of urea and dissolve them in 20mL of deionized water. Stir at room temperature until dissolved to obtain solution A.

[0058] (3) Weigh 18 mg of ruthenium chloride, 15 mg of indium nitrate and 13 mg of boric acid and dissolve them in 10 mL of deionized water. Stir at room temperature until dissolved to obtain solution B.

[0059] (4) Mix solutions A and B thoroughly and stir at room temperature for 30 min until completely dissolved. Transfer to a 50 mL hydrothermal reactor, set the hydrothermal temperature to 100 °C and the hydrothermal time to 6 h to obtain the sol-sol precursor.

[0060] (5) The sol-sol precursor was washed five times each with deionized water and anhydrous ethanol. The supernatant was discarded. The sol-sol was dried in a vacuum drying oven at 60°C for 18 hours and then ground into powder in a mortar.

[0061] (6) The powder was sintered in a tube furnace with air as the gas atmosphere to form a black powder. The reaction temperature was set at 500℃, the heating rate was 2℃ / min, and the reaction time was 16h to obtain a boron and indium dual-element doped and modified ruthenium oxide BIn-RuO2 catalyst.

[0062] (7) Take 5 mg of the obtained BIn-RuO2 catalyst, use 460 μL of ethanol as a dispersant and 40 μL of 5 wt% Nafion 117 solution as a binder to drop the catalyst onto the carbon paper pretreated in (1), and put it into an oven at 60 °C to dry to obtain the BIn-RuO2 electrode.

[0063] (8) The composite electrode prepared above was used for the electrocatalytic oxygen evolution reaction (OER). The specific steps were as follows: a three-electrode system was constructed, in which the working electrode was a BIn-RuO2 electrode, the reference electrode was a silver / silver chloride electrode, and the counter electrode was a carbon rod. The OER performance was tested in an oxygen-saturated 0.5 mol / L sulfuric acid solution. The results showed that BIn-RuO2 required an overpotential of 182 mV to achieve 10 mA cm⁻¹. -2 It has a current density that can be maintained for more than 300 hours without decay.

[0064] Comparative Example 1

[0065] The preparation method of the boron-doped ruthenium oxide electrocatalytic electrode is as follows:

[0066] (1) Cut carbon paper into 1cm×2cm pieces, and then hydrothermally heat the cut carbon paper in diluted concentrated nitric acid (HNO3:H2O volume ratio of 1:1) at 150℃ for 6h. After taking it out, place it in ethanol and water and sonicate for 30min in sequence, and then dry it at 70℃ for 6h to obtain the treated conductive substrate carbon paper.

[0067] (2) Weigh 3g of glucose and 0.6g of urea and dissolve them in 10mL of deionized water. Stir at room temperature until dissolved to obtain solution A.

[0068] (3) Weigh 30 mg of ruthenium chloride and 26 mg of boric acid and dissolve them in 10 mL of deionized water. Stir at room temperature until dissolved to obtain solution B.

[0069] (4) Mix solutions A and B thoroughly and stir at room temperature for 30 minutes until completely dissolved. Transfer to a 50 mL hydrothermal reactor, set the hydrothermal temperature to 160 °C and the hydrothermal time to 8 h to obtain a sol solid.

[0070] (5) The sol solids were washed three times by centrifugation with deionized water and anhydrous ethanol respectively. The supernatant was discarded and the sol solids were dried in a vacuum drying oven at 70°C for 12 hours.

[0071] (6) The obtained sol solid was ground into powder in a mortar. In a tube furnace, it was sintered under an air atmosphere, with a reaction temperature of 400℃, a heating rate of 5℃ / min, and a reaction time of 12h to obtain boron-doped ruthenium oxide B-RuO2 electrocatalyst.

[0072] (7) Take 5 mg of the obtained B-RuO2 catalyst, use 460 μL of ethanol as a dispersant and 40 μL of 5 wt% Nafion 117 solution as a binder to drop-coat the B-RuO2 catalyst onto the carbon paper pretreated in (1). Place it in an oven at 60 °C to dry and obtain the B-RuO2 electrode for later use.

[0073] (8) The composite electrode prepared above was used for the electrocatalytic oxygen evolution reaction. The specific steps were as follows: a three-electrode system was constructed, in which the working electrode was a B-RuO2 electrode, the reference electrode was a silver / silver chloride electrode, and the counter electrode was a carbon rod. The OER performance was tested in an oxygen-saturated 0.5 mol / L sulfuric acid solution.

[0074] Comparative Example 2

[0075] The gallium-doped ruthenium oxide electrocatalytic electrode is prepared by the following method:

[0076] (1) Cut carbon paper into 1cm×2cm pieces, and then hydrothermally heat the cut carbon paper in diluted concentrated nitric acid (HNO3:H2O volume ratio of 1:1) at 150℃ for 6h. After taking it out, place it in ethanol and water and sonicate for 30min in sequence, and then dry it at 70℃ for 6h to obtain the treated conductive substrate carbon paper.

[0077] (2) Weigh 3g of glucose and 0.6g of urea and dissolve them in 10mL of deionized water. Stir at room temperature until dissolved to obtain solution A.

[0078] (3) Weigh 30 mg of ruthenium chloride and 36.8 mg of gallium nitrate and dissolve them in 10 mL of deionized water. Stir at room temperature until dissolved to obtain solution B.

[0079] (4) Mix solutions A and B thoroughly and stir at room temperature for 30 minutes until completely dissolved. Transfer to a 50 mL hydrothermal reactor, set the hydrothermal temperature to 160 °C and the hydrothermal time to 8 h to obtain a sol solid.

[0080] (5) The sol solids were washed three times by centrifugation with deionized water and anhydrous ethanol respectively. The supernatant was discarded and the sol solids were dried in a vacuum drying oven at 70°C for 12 hours.

[0081] (6) The obtained sol solid was ground into fine powder in a mortar. In a tube furnace, it was sintered under an air atmosphere, with a reaction temperature of 400℃, a heating rate of 5℃ / min, and a reaction time of 12h to obtain a gallium-doped ruthenium oxide Ga-RuO2 electrocatalyst.

[0082] (7) Take 5 mg of the obtained Ga-RuO2 catalyst, use 460 μL of ethanol as a dispersant and 40 μL of 5 wt% Nafion 117 solution as a binder to drop-coat the catalyst onto the carbon paper pretreated in (1). Place it in an oven at 60 °C to dry and obtain the Ga-RuO2 electrode for later use.

[0083] (8) The composite electrode prepared above was used for the electrocatalytic oxygen evolution reaction. The specific steps were as follows: a three-electrode system was constructed, in which the working electrode was a Ga-RuO2 electrode, the reference electrode was a silver / silver chloride electrode, and the counter electrode was a carbon rod. The OER performance was tested in an oxygen-saturated 0.5 mol / L sulfuric acid solution.

[0084] Comparative Example 3

[0085] The porous ruthenium oxide electrocatalytic electrode is prepared by the following method:

[0086] (1) Cut carbon paper into 1cm×2cm pieces, and then hydrothermally heat the cut carbon paper in diluted concentrated nitric acid (HNO3:H2O volume ratio of 1:1) at 150℃ for 6h. After taking it out, place it in ethanol and water and sonicate for 30min in sequence, and then dry it at 70℃ for 6h to obtain the treated conductive substrate carbon paper.

[0087] (2) Weigh 3g of glucose and 0.6g of urea and dissolve them in 10mL of deionized water. Stir at room temperature until dissolved to obtain solution A.

[0088] (3) Weigh 30 mg of ruthenium chloride and dissolve it in 10 mL of deionized water. Stir at room temperature until dissolved to obtain solution B.

[0089] (4) Mix solutions A and B thoroughly and stir at room temperature for 30 minutes until completely dissolved. Transfer to a 50 mL hydrothermal reactor, set the hydrothermal temperature to 160 °C and the hydrothermal time to 8 h to obtain a sol solid.

[0090] (5) The sol solids were washed three times by centrifugation with deionized water and anhydrous ethanol respectively. The supernatant was discarded and the sol solids were dried in a vacuum drying oven at 70°C for 12 hours.

[0091] (6) The obtained sol solid was ground into fine powder in a mortar. In a tube furnace, it was sintered under air atmosphere, with the reaction temperature set at 400℃, the heating rate at 5℃ / min, and the reaction time at 12h to obtain the self-made porous ruthenium oxide Home-RuO2 catalyst.

[0092] (7) Take 5 mg of the obtained Home-RuO2 catalyst, use 460 μL of ethanol as a dispersant and 40 μL of 5 wt% Nafion 117 solution as a binder to drop-coat the Home-RuO2 catalyst onto the carbon paper pretreated in (1), and dry it in an oven at 60 °C to obtain the Home-RuO2 electrode for later use.

[0093] (8) The Home-RuO2 electrode prepared above was used for the electrocatalytic oxygen evolution reaction. The specific steps were as follows: a three-electrode system was constructed, in which the working electrode was the Home-RuO2 electrode, the reference electrode was a silver / silver chloride electrode, and the counter electrode was a carbon rod. The OER performance was tested in an oxygen-saturated 0.5 mol / L sulfuric acid solution.

[0094] Figure 1 The image shown is a scanning electron microscope (SEM) image of BGa-RuO2 obtained in Example 1. Figure 1 It can be observed that the BGa-RuO2 catalyst is composed of densely packed nanospheres with a size of 40-60 nm. This structure increases the electrochemical active surface area of ​​the catalyst, increases the number of active sites, and effectively improves the electrocatalytic performance of the catalyst.

[0095] Figure 2 The image shows the elemental mapping of BGa-RuO2 obtained in Example 1. The image shows the successful incorporation of B, Ga, and Ru elements, and their uniform distribution in the material.

[0096] Figure 3 The X-ray diffraction (XRD) spectra of the electrodes obtained in Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3 show that the peaks of the XRD spectra corresponding to B or Ga doping alone did not shift compared to ruthenium oxide, indicating that the crystal structure of RuO2 was not changed after doping. Similarly, the peaks of the XRD spectra of RuO2 modified with both B and Ga doping did not shift compared to ruthenium oxide, indicating that B and Ga doping resulted in amorphous or smaller forms.

[0097] Figure 4The figure shows the electrocatalytic oxygen evolution performance of electrodes obtained from Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3, and commercial RuO2. The OER linear voltammetry images were acquired at a scan rate of 5 mV / s in a 0.5 mol / L sulfuric acid solution. The figure shows that BGa-RuO2, B-RuO2, Ga-RuO2, Home-RuO2, and Com-RuO2 exhibited better performance at 10 mA / cm². -2 The overpotentials at these times were 170 mV, 183 mV, 192 mV, 232 mV, and 280 mV, respectively. In comparison, the BGa-RuO2 anode electrocatalyst electrode exhibits excellent electrocatalytic oxygen evolution performance. The introduction of boron lowers the crystal structure of the catalyst. Compared to crystalline materials, the amorphous structure not only provides significant active sites but also actively modulates the Ru-O bond and optimizes the adsorption energy of oxygen intermediates, thus achieving a significant improvement in activity. Furthermore, the electronic spatial regulation of B optimizes the bimetallic synergistic effect between the doped metal element and Ru. The combined synergistic effect between nonmetallic B and the doped metal element optimizes the catalytic activity of RuO2. Moreover, doping suppresses the dissolution effect of Ru, effectively improving the acid resistance and stability of RuO2 in the OER process. This allows the BGa-RuO2 anode to achieve 10 mA cm⁻¹ with only a 170 mV overpotential. -2 It has a high current density and excellent OER performance.

[0098] Figure 6 The image shows Home-RuO2 at 10 mA / cm². -2 The chronocurrent stability plot at the current density shows that Home-RuO2 is stable for about 120 hours. After that, the overpotential rises sharply and it loses its activity. Figure 5 The image shows BGa-RuO2 at 10 mA / cm². -2 The chronocurrent stability plot at a given current density shows that it maintains stability for over 1400 hours, with the overpotential increasing by only about 100 mV, demonstrating its excellent OER stability in acidic media. In contrast, other dual-element doped ruthenium oxide electrodes, such as InSnRuO2, exhibit stability at 10 mA cm⁻¹. -2 The overpotential at the anode is 183mV, and it can operate stably for 200h. Compared with BGa-RuO2 anode, it has greatly improved in terms of catalytic activity and stability, and has the value of replacing Ir-based catalysts for large-scale commercial application.

[0099] The embodiments described above are merely illustrative of implementation methods of the present invention and should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the protection scope of the present invention.

Claims

1. A method for preparing a boron and metal co-doped modified ruthenium oxide anode catalyst, characterized in that, The ruthenium oxide anode catalyst has a compact nanosphere shape, and the nanosphere size is 40-60nm, wherein the molar ratio of boron, doped metal and ruthenium is (3-3.3):(3-0.2):1, and the doped metal is gallium, indium or aluminum; and the preparation method comprises the following steps: Step 1, a certain amount of glucose and urea are dissolved in deionized water to obtain a mixed solution A; Step 2, a certain amount of ruthenium chloride, nitrate hydrate and boric acid are dissolved in deionized water to obtain a mixed solution B; the nitrate hydrate is gallium nitrate hydrate, indium nitrate hydrate or aluminum nitrate hydrate; Step 3, the mixed solution A and the mixed solution B are uniformly mixed to obtain a precursor mixed solution C; Step 4, the precursor solution C is placed in a hydrothermal kettle, and hydrothermal operation is carried out in an oven, and a gel solid precursor is obtained after washing; Step 5, the obtained gel solid precursor is dried in a vacuum drying box, and the obtained solid product is ground into powder; Step 6, the powder is sintered in a tube furnace to form a black powder with air as the gas atmosphere, and the black powder is cooled to room temperature to obtain a boron and metal double-doped modified ruthenium oxide anode catalyst.

2. The method for preparing a boron and metal co-doped modified ruthenium oxide anode catalyst according to claim 1, characterized in that, In step 1, the concentrations of glucose and urea in the mixed solution A are 0.4-1mol / L and 0.1-0.6mol / L, respectively.

3. The method for preparing a boron and metal co-doped modified ruthenium oxide anode catalyst according to claim 1, characterized in that, In step 2, the concentrations of ruthenium chloride, nitrate hydrate and boric acid in the mixed solution B are 0.05-0.1mol / L, 0.02-0.15mol / L and 0.15-0.33mol / L, respectively.

4. The method for preparing a boron and metal co-doped modified ruthenium oxide anode catalyst according to claim 3, characterized in that, The nitrate hydrate is gallium nitrate hydrate.

5. The method for preparing a boron and metal co-doped modified ruthenium oxide anode catalyst according to claim 1, characterized in that, In step 3, the volume ratio of the mixed solution A to the mixed solution B is 1:1-2:

1.

6. The method for preparing a boron and metal co-doped modified ruthenium oxide anode catalyst according to claim 1, characterized in that, In step 4, the hydrothermal temperature is 100-180℃, the hydrothermal time is 6-12h, and after hydrothermal treatment, the gel is washed with anhydrous ethanol and deionized water in a centrifuge for 3-5 times until the upper liquid is clear and transparent.

7. The method for preparing a boron and metal co-doped modified ruthenium oxide anode catalyst according to claim 1, characterized in that, In step 6, the sintering process is as follows: the temperature is raised to 400-500℃ at a temperature rising speed of 2-5℃ / min, and the temperature is kept for 8-16h.

8. A boron and metal double-doped modified ruthenium oxide anode catalyst prepared by the preparation method of any one of claims 1-7.

9. The use of a boron and metal co-doped modified ruthenium oxide anode catalyst according to claim 8, characterized in that, It is used as an electrode material for electrocatalytic oxygen evolution reaction.

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