A Ru-doped SrFeO 3-δ Trifunctional perovskite electrocatalytic material and preparation method and application thereof

Abstract

This invention belongs to the field of electrocatalytic materials technology, and particularly relates to a Ru-doped SrFeO 3‑δ Trifunctional perovskite electrocatalytic materials, their preparation methods, and applications. The electrocatalytic material is Ru-doped SrFeO. 3‑δ Perovskite oxides containing trace amounts of the noble metal Ru effectively enhance the performance of SrFeO. 3‑δ The electrocatalytic activity of perovskite oxides alleviates the problem of the scarcity of precious metals in nature. The electrocatalyst provided by this invention exhibits excellent HER, OER, and ORR catalytic activity, and can be used in technologies such as water electrolysis, fuel cells, and metal-air batteries, possessing good catalytic activity and stability. The preparation method of this invention is simple, safe, environmentally friendly, and has good economic benefits. The Ru-doped SrFeO prepared by this method... 3‑δ The trifunctional perovskite electrocatalytic material has a nanoparticle structure with a small particle size, which increases the electrochemical active area of ​​the catalyst and thus improves its electrocatalytic activity. It has good application potential in the field of new energy.

Description

Technical Field

[0001] This invention belongs to the field of electrocatalytic materials technology, and particularly relates to a Ru-doped SrFeO 3-δ Trifunctional perovskite electrocatalytic materials, their preparation methods, and applications. Background Technology

[0002] The hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) are key electrode reactions in many new energy technologies (such as water electrolysis, fuel cell technology, and metal-air battery technology). However, their slow kinetics greatly limit their application. Therefore, the development of efficient and stable electrocatalysts plays a crucial role in the field of new energy storage and conversion. In particular, the development of bifunctional or even trifunctional electrocatalysts with simultaneous HER, OER, and ORR activities has attracted widespread attention. In recent years, noble metal-based electrocatalysts (such as IrO2, RuO2, Pt, and Pt alloys) have been considered the best catalysts for HER, OER, and ORR processes. However, their industrial production is limited by drawbacks such as high cost, low storage capacity, low stability, and limited functionality, and they are still not widely used. To overcome these problems, non-noble metal compounds (such as perovskite oxides and spinel oxides), which are abundant in raw materials, low in cost, diverse in variety, and have excellent electrocatalytic performance, are gradually becoming alternative electrocatalysts.

[0003] However, the electrocatalytic performance of most non-noble metal catalysts is still inferior to that of commercial catalysts. To further improve their electrocatalytic activity and reduce the overpotential of energy conversion processes, appropriate noble metal doping is an effective strategy. Among noble metals, Ru has a metal-hydrogen bond strength similar to Pt, but Ru is much cheaper than Pt (approximately 1 / 5 the price of Pt). Therefore, doping non-noble metal catalysts with Ru is an effective way to improve performance and reduce costs. For example, a Ru-doped CoS catalyst is disclosed in the prior art. 1.097 The catalyst preparation method uses ZIF-67 as a precursor. Ru is doped into ZIF-67 via an oil bath immersion method, followed by a one-step hydrothermal reaction at 200℃ for 20 h. After washing and drying, the catalyst is obtained. Results show that the catalyst exhibits excellent electrocatalytic hydrogen evolution performance and good stability in an alkaline environment. A Ru-doped W catalyst is also disclosed in the prior art. 4.6 A method for preparing N4 particles@nitrogen-doped graphene tube hydrogen evolution electrocatalysts is described, which first utilizes a hydrothermal method to in-situ grow Ru-doped WO3 on a nitrogen-doped graphene tube support. x The precursor was then heated and nitrided in a tube furnace to obtain nitrogen-doped graphene tubes and Ru-doped W grown in situ on their surface. 4.6Hydrogen evolution electrocatalyst composed of N4 nanoparticles, based on Ru doping of W 4.6 The effective modulation of the N4 electronic structure and the synergistic effect of the good conductivity of the nitrogen-doped graphene tube support resulted in this electrocatalyst exhibiting good electrocatalytic activity and stability in alkaline media. However, the electrocatalytic performance of the aforementioned Ru-doped electrocatalysts still suffers from limitations such as a single activity type. Therefore, developing a Ru-doped electrocatalyst with excellent HER / ORR / OER trifunctional properties is an urgent problem to be solved. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a SrFe 1-x Ru x O 3-δ Trifunctional perovskite electrocatalytic materials, their preparation methods and applications, and the SrFe described in this invention. 1-x Ru x O 3-δ Perovskite electrocatalytic materials exhibit excellent electrocatalytic activities for HER, OER, and ORR, making them a trifunctional electrocatalyst with good stability.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A Ru-doped SrFeO 3-δ Trifunctional perovskite electrocatalytic material, wherein the material is SrFe 1-x Ru x O 3-δ The perovskite oxide has a x of 0.05–0.40; its microstructure is a nanoparticle structure with a particle size of 10–100 nm; the material belongs to the tetragonal crystal system; the overpotential of the perovskite material HER is 40–180 mV vs. RHE, the overpotential of OER is 330–370 mV vs. RHE, and the half-wave potential of ORR is 0.58–0.63 V vs. RHE.

[0007] Preferably, x is 0.3, 0.4, or 0.05.

[0008] This invention also provides a Ru-doped SrFeO as described above. 3-δ A method for preparing trifunctional perovskite electrocatalytic materials. The method is characterized by using polyvinylpyrrolidone as a complex and nitric acid-treated ruthenium dioxide as a ruthenium source, employing a modified sol-gel method to prepare nanoscale Ru-doped perovskite oxide materials.

[0009] The above Ru-doped SrFeO 3-δ The preparation method of the trifunctional perovskite electrocatalytic material includes the following steps:

[0010] (1) Strontium nitrate, ferric nitrate and ruthenium dioxide are mixed with polyvinylpyrrolidone at room temperature, and then deionized water, nitric acid, N,N-dimethylformamide and anhydrous ethanol are added and stirred until uniform to obtain a sol;

[0011] (2) The sol described in step (1) is dried under vacuum to obtain a gel;

[0012] (3) Sinter the gel described in step (2) to obtain the Ru-doped SrFeO. 3-δ Trifunctional perovskite electrocatalytic materials.

[0013] The room temperature mentioned in this invention refers to 20-25℃.

[0014] Preferably, the molar ratio of strontium nitrate, ferric nitrate and ruthenium dioxide in step (1) is 10:(6-10):(0-4).

[0015] Preferably, the mass ratio of strontium nitrate to polyvinylpyrrolidone in step (1) is (0.96-1.33):1.

[0016] Preferably, the volume ratio of deionized water, nitric acid, N,N-dimethylformamide and anhydrous ethanol in step (1) is 2:(0-0.3):1:(3-9).

[0017] Preferably, the stirring time in step (1) is 8-10 hours and the stirring speed is 600 rpm / min.

[0018] Preferably, the drying temperature in step (2) is 80-100℃ and the drying time is 12-14h.

[0019] Preferably, in step (3), the first sintering is performed by heating from room temperature to 200-350°C at a rate of 2-5°C / min for 1-2 hours, followed by cooling and grinding; the second sintering is performed by heating from room temperature to 750-900°C at a rate of 2-5°C / min for 5-8 hours.

[0020] The present invention also provides the above-mentioned Ru-doped SrFeO 3-δ Applications of trifunctional perovskite electrocatalytic materials in water electrolysis, fuel cell technology, and metal-air battery technology.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] (1) The Ru-doped SrFeO provided by this invention 3-δTrifunctional perovskite electrocatalysts improve catalytic efficiency by adjusting the ratio of Fe to Ru, which not only alleviates the problem of the scarcity of precious metals in nature, but also enhances the electrocatalytic activity and stability of perovskite oxides.

[0023] (2) Ru-doped SrFeO prepared in this invention 3-δ The trifunctional perovskite electrocatalytic material has a nanoparticle structure and a small particle size, which increases the active surface area of ​​the catalyst and thus improves its electrocatalytic activity.

[0024] (3) The electrocatalyst described in this invention has excellent HER, OER and ORR catalytic activity, and can be used in technologies such as water electrolysis, fuel cells and metal-air batteries with good catalytic activity. It has good application prospects in new energy fields such as water electrolysis and batteries.

[0025] (4) The preparation method described in this invention improves the traditional sol-gel method by using polyvinylpyrrolidone as a complex and ruthenium dioxide treated with nitric acid as a ruthenium source, thus simply and effectively preparing a three-functional perovskite electrocatalytic material with nanoscale. Compared with solid-phase synthesis and other chemical synthesis methods, this method significantly reduces the catalyst synthesis temperature and synthesis time. Moreover, the preparation method is simple, the conditions are easy to achieve, the cost is low, it is safe and environmentally friendly, and it has good economic benefits. It can be produced on a large scale and has good application prospects. Attached Figure Description

[0026] Figure 1 The SrFe prepared in Examples 1, 2, 3, 4, 5, and 6 of this invention 1-x Ru x O 3-δ Comparative SrFeO 3-δ X-ray diffraction pattern of perovskite electrocatalytic materials.

[0027] Figure 2 The SrFe prepared in Examples 1, 2, and 4 of this invention 1-x Ru x O 3-δ Comparative SrFeO 3-δ Scanning electron microscope image of perovskite electrocatalytic materials.

[0028] Figure 3 The SrFe prepared in Example 1 of this invention 1-x Ru x O 3-δ Transmission electron microscope image of a trifunctional perovskite electrocatalytic material.

[0029] Figure 4 The SrFe prepared in Examples 1, 2, 3, 4, 5, and 6 of this invention1-x Ru x O 3-δ Comparative SrFeO 3-δ HER polarization curves of perovskite electrocatalysts in N2-saturated 1M KOH solution at a scan rate of 10 mV / s.

[0030] Figure 5 The SrFe prepared in Example 1 of the present invention 1-x Ru x O 3-δ Trifunctional perovskite electrocatalyst material in 1 M KOH solution at -10 mA / cm -2 The stability test diagram was obtained under the current density conditions.

[0031] Figure 6 The SrFe prepared in Examples 1, 2, 3, 4, 5, and 6 of this invention 1-x Ru x O 3-δ Comparative SrFeO 3-δ OER polarization curves of perovskite electrocatalysts in O2-saturated 1M KOH solution at a scan rate of 10 mV / s.

[0032] Figure 7 The SrFe prepared in Example 1 of the present invention 1-x Ru x O 3-δ Perovskite electrocatalyst material in 1M KOH solution at 10 mA / cm² -2 The stability test diagram was obtained under the current density conditions.

[0033] Figure 8 The Ru-doped SrFeO prepared in Examples 1, 2, 3, 4, 5, and 6 of this invention 3-δ Comparative SrFeO 3-δ ORR polarization curves of perovskite electrocatalysts in O2-saturated 0.1M KOH solution at a scan rate of 10 mV / s.

[0034] Figure 9 The Ru-doped SrFeO prepared in Examples 1, 2, 3, 4, 5, and 6 of this invention 3-δ Comparative SrFeO 3-δ Impedance diagram of perovskite electrocatalytic materials.

[0035] Figure 10 The Ru-doped SrFeO prepared in Example 1 of this invention 3-δPolarization curves of a water electrolysis system composed of a trifunctional perovskite electrocatalyst and a water electrolysis system composed of commercial Pt / C and commercial RuO2 in 1M KOH solution, with a scan rate of 10mV / s.

[0036] Figure 11 The Ru-doped SrFeO prepared in Example 1 of this invention 3-δ An electrolysis system composed of a trifunctional perovskite electrocatalyst and an electrolysis system composed of commercial Pt / C and commercial RuO2 were tested in 1M KOH solution at 10 mA cm⁻¹. -2 The stability test diagram was obtained under the current density conditions. Detailed Implementation

[0037] The present invention will now be described in detail. The following embodiments are merely examples illustrating implementations of the present invention and do not constitute any limitation thereof. Those skilled in the art will understand that modifications made without departing from the spirit and concept of the present invention fall within its protection scope. Unless otherwise specified, the reagents and instruments used in the following embodiments are commercially available products.

[0038] Terminology Explanation:

[0039] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0040] Example 1

[0041] This embodiment provides a Ru-doped SrFeO 3-δ Trifunctional perovskite electrocatalyst material SrFe 0.7 Ru 0.3 O 3-δ It is prepared by the following method:

[0042] (1) Weigh 10 mmol of strontium nitrate, 7 mmol of ferric nitrate, 3 mmol of ruthenium dioxide, and 1.9 g of polyvinylpyrrolidone and dissolve them in a mixed solution of 8 mL of deionized water, 1.2 mL of nitric acid, 4 mL of N,N-dimethylformamide and 16 mL of anhydrous ethanol. Stir magnetically at room temperature for 9 h to obtain a uniformly mixed sol.

[0043] (2) The sol obtained in step (1) is transferred to a vacuum drying oven and dried at 90°C for 12 hours to obtain a brown gel.

[0044] (3) The brown gel obtained in step (2) is placed in a tube furnace for the first step of sintering. The temperature is set to rise from room temperature to 300℃ at a rate of 3℃ / min. Then, it is calcined at 300℃ for 1 hour. After cooling, it is ground to obtain a black powder sample.

[0045] (4) The black powder sample obtained in step (3) is placed in a tube furnace for the second sintering step. The temperature is set to rise from room temperature to 800℃ at a rate of 3℃ / min. Then, it is calcined at 800℃ for 6 hours. After cooling, it is ground to obtain the final sample.

[0046] Upon testing, the phase structure of the sample in this embodiment is as follows: Figure 1 As shown in the figure, the material is a perovskite oxide.

[0047] The perovskite electrocatalyst material SrFe prepared in this embodiment 0.7 Ru 0.3 O 3-δ The scanning electron microscope (SEM) and transmission electron microscope (TEM) results are as follows: Figure 2 , 3 As shown in the figure, the prepared sample has a nanoparticle structure with a particle size of 10-100 nm.

[0048] The perovskite electrocatalyst material SrFe prepared in this embodiment 0.7 Ru 0.3 O 3-δ Electrocatalytic performance such as Figures 4-8 As shown in the figure, the perovskite electrocatalyst material SrFe prepared in this example can be seen from the figure. 0.7 Ru 0.3 O 3-δ It exhibits excellent electrocatalytic performance in HER, OER, and ORR, and good stability. Its impedance results are as follows: Figure 9 As shown, the results demonstrate that the perovskite electrocatalyst material SrFe 0.7 Ru 0.3 O 3-δ It has a very small charge transfer rate.

[0049] Example 2

[0050] This embodiment provides a Ru-doped SrFeO 3-δ Trifunctional perovskite electrocatalyst material SrFe 0.8 Ru 0.2 O 3-δ It is prepared by the following method:

[0051] (1) Weigh 10 mmol of strontium nitrate, 8 mmol of ferric nitrate, 2 mmol of ruthenium dioxide, and 2.0 g of polyvinylpyrrolidone and dissolve them in a mixed solution of 8 mL of deionized water, 0.8 mL of nitric acid, 4 mL of N,N-dimethylformamide and 20 mL of anhydrous ethanol. Stir magnetically at room temperature for 8 h to obtain a uniformly mixed sol.

[0052] (2) The sol obtained in step (1) is transferred to a vacuum drying oven and dried at 80°C for 12 hours to obtain a brown gel.

[0053] (3) The brown gel obtained in step (2) was placed in a tube furnace for the first step of sintering. The temperature was set to rise from room temperature to 350°C at a rate of 5°C / min. Then, it was calcined at 350°C for 1.5 hours. After cooling, it was ground to obtain a black powder sample.

[0054] (4) The black powder sample obtained in step (3) is placed in a tube furnace for the second sintering step. The temperature is set to rise from room temperature to 750°C at a rate of 5°C / min. Then, it is calcined at 750°C for 6 hours. After cooling, it is ground to obtain the final sample.

[0055] Upon testing, the phase structure of the sample in this embodiment is as follows: Figure 1 As shown in the figure, the material is a perovskite oxide.

[0056] The perovskite electrocatalyst material SrFe prepared in this embodiment 0.8 Ru 0.2 O 3-δ The scanning electron microscope (SEM) results are as follows: Figure 2 As shown in the figure, the prepared sample has a nanoparticle structure with a particle size of 10-100 nm.

[0057] The perovskite electrocatalyst material SrFe prepared in this embodiment 0.8 Ru 0.2 O 3-δ Electrocatalytic performance such as Figure 4 , 6 As shown in Figure 8, the perovskite electrocatalyst material SrFe prepared in this example can be seen from the figure. 0.8 Ru 0.2 O 3-δ It exhibits superior electrocatalytic performance in HER, OER, and ORR. Its impedance results are as follows: Figure 9 As shown, the results demonstrate that the perovskite electrocatalyst material SrFe 0.8 Ru 0.2 O 3-δ It has a relatively small charge transfer rate.

[0058] Example 3

[0059] This embodiment provides a Ru-doped SrFeO 3-δ Trifunctional perovskite electrocatalyst material SrFe 0.85 Ru 0.15 O 3-δ It is prepared by the following method:

[0060] (1) Weigh 10 mmol of strontium nitrate, 8.5 mmol of ferric nitrate, 1.5 mmol of ruthenium dioxide and 1.8 g of polyvinylpyrrolidone and dissolve them in a mixed solution of 8 mL of deionized water, 0.4 mL of nitric acid, 4 mL of N,N-dimethylformamide and 32 mL of anhydrous ethanol. Stir magnetically at room temperature for 9 h to obtain a uniformly mixed sol.

[0061] (2) The sol obtained in step (1) was transferred to a vacuum drying oven and dried at 80°C for 13 hours to obtain a brown gel.

[0062] (3) The brown gel obtained in step (2) is placed in a tube furnace for the first step of sintering. The temperature is set to rise from room temperature to 300°C at a rate of 4°C / min. Then, it is calcined at 300°C for 1 hour. After cooling, it is ground to obtain a black powder sample.

[0063] (4) The black powder sample obtained in step (3) is placed in a tube furnace for the second sintering step. The temperature is set to rise from room temperature to 850°C at a rate of 4°C / min. Then, it is calcined at 850°C for 7 hours. After cooling, it is ground to obtain the final sample.

[0064] Upon testing, the phase structure of the sample in this embodiment is as follows: Figure 1 As shown in the figure, the material is a perovskite oxide.

[0065] The perovskite electrocatalyst material SrFe prepared in this embodiment 0.85 Ru 0.15 O 3-δ Electrocatalytic performance such as Figure 4 , 6 As shown in Figure 8, the perovskite electrocatalyst material SrFe prepared in this example can be seen from the figure. 0.85 Ru 0.15 O 3-δ It exhibits superior electrocatalytic performance in HER, OER, and ORR. Its impedance results are as follows: Figure 9 As shown, the results demonstrate that the perovskite electrocatalyst material SrFe 0.85 Ru 0.15 O 3-δ It has a large charge transfer rate.

[0066] Example 4

[0067] This embodiment provides a Ru-doped SrFeO 3-δ Trifunctional perovskite electrocatalyst material SrFe 0.9 Ru 0.1 O 3-δ It is prepared by the following method:

[0068] (1) Weigh 10 mmol of strontium nitrate, 9 mmol of ferric nitrate, 1 mmol of ruthenium dioxide, and 2.1 g of polyvinylpyrrolidone and dissolve them in a mixed solution of 8 mL of deionized water, 0.4 mL of nitric acid, 4 mL of N,N-dimethylformamide and 24 mL of anhydrous ethanol. Stir magnetically at room temperature for 10 h to obtain a uniformly mixed sol.

[0069] (2) The sol obtained in step (1) is transferred to a vacuum drying oven and dried at 100°C for 14 hours to obtain a brown gel.

[0070] (3) The brown gel obtained in step (2) is placed in a tube furnace for the first step of sintering. The temperature is set to rise from room temperature to 200°C at a rate of 4°C / min. Then, it is calcined at 200°C for 2 hours. After cooling, it is ground to obtain a black powder sample.

[0071] (4) The black powder sample obtained in step (3) is placed in a tube furnace for the second sintering step. The temperature is set to rise from room temperature to 900℃ at a rate of 4℃ / min. Then, it is calcined at 900℃ for 8 hours. After cooling, it is ground to obtain the final sample.

[0072] Upon testing, the phase structure of the sample in this embodiment is as follows: Figure 1 As shown in the figure, the material is a perovskite oxide.

[0073] The perovskite electrocatalyst material SrFe prepared in this embodiment 0.9 Ru 0.1 O 3-δ The scanning electron microscope (SEM) results are as follows: Figure 2 As shown. From Figure 2 It can be seen that the prepared sample has a nanoparticle structure with a particle size of 10-100 nm.

[0074] The perovskite electrocatalyst material SrFe prepared in this embodiment 0.9 Ru 0.1 O 3-δ Electrocatalytic performance such as Figure 4 , 6 As shown in Figure 8, the perovskite electrocatalyst material SrFe prepared in this example can be seen from the figure.0.9 Ru 01 O 3-δ It exhibits good electrocatalytic performance in HER, OER, and ORR. Its impedance results are as follows: Figure 9 As shown, the results demonstrate that the perovskite electrocatalyst material SrFe 0.9 Ru 0.1 O 3-δ It has a large charge transfer rate.

[0075] Example 5

[0076] This embodiment provides a Ru-doped SrFeO 3-δ Trifunctional perovskite electrocatalyst material SrFe 0.95 Ru 0.05 O 3-δ It is prepared by the following method:

[0077] (1) Weigh 10 mmol of strontium nitrate, 9.5 mmol of ferric nitrate, 0.5 mmol of ruthenium dioxide, and 1.6 g of polyvinylpyrrolidone and dissolve them in a mixed solution of 8 mL of deionized water, 0.8 mL of nitric acid, 4 mL of N,N-dimethylformamide and 12 mL of anhydrous ethanol. Stir magnetically at room temperature for 10 h to obtain a uniformly mixed sol.

[0078] (2) The sol obtained in step (1) is transferred to a vacuum drying oven and dried at 80°C for 12 hours to obtain a brown gel.

[0079] (3) The brown gel obtained in step (2) is placed in a tube furnace for the first step of sintering. The temperature is set to rise from room temperature to 350°C at a rate of 3°C / min. Then, it is calcined at 350°C for 2 hours. After cooling, it is ground to obtain a black powder sample.

[0080] (4) The black powder sample obtained in step (3) is placed in a tube furnace for the second sintering step. The temperature is set to rise from room temperature to 750°C at a rate of 3°C / min. Then, it is calcined at 750°C for 8 hours. After cooling, it is ground to obtain the final sample.

[0081] Upon testing, the phase structure of the sample in this embodiment is as follows: Figure 1 As shown in the figure, the material is a perovskite oxide.

[0082] The perovskite electrocatalyst material SrFe prepared in this embodiment 0.95 Ru 0.05 O 3-δ Electrocatalytic performance such as Figure 4 , 6As shown in Figure 8, the perovskite electrocatalyst material SrFe prepared in this example can be seen from the figure. 0.95 Ru 0.05 O 3-δ It exhibits superior electrocatalytic performance in HER, OER, and ORR. Its impedance results are as follows: Figure 9 As shown, the results demonstrate that the perovskite electrocatalyst material SrFe 0.95 Ru 0.05 O 3-δ It has a large charge transfer rate.

[0083] Example 6

[0084] This embodiment provides a Ru-doped SrFeO 3-δ Trifunctional perovskite electrocatalyst material SrFe 0.6 Ru 0.4 O 3-δ It is prepared by the following method:

[0085] (1) Weigh 10 mmol of strontium nitrate, 6 mmol of ferric nitrate, 4 mmol of ruthenium dioxide, and 1.7 g of polyvinylpyrrolidone and dissolve them in a mixed solution of 8 mL of deionized water, 1.2 mL of nitric acid, 4 mL of N,N-dimethylformamide and 36 mL of anhydrous ethanol. Stir magnetically at room temperature for 8 h to obtain a uniformly mixed sol.

[0086] (2) The sol obtained in step (1) was transferred to a vacuum drying oven and dried at 90°C for 14 hours to obtain a brown gel.

[0087] (3) The brown gel obtained in step (2) is placed in a tube furnace for the first step of sintering. The temperature is set to rise from room temperature to 250°C at a rate of 5°C / min. Then, it is calcined at 250°C for 2 hours. After cooling, it is ground to obtain a black powder sample.

[0088] (4) The black powder sample obtained in step (3) is placed in a tube furnace for the second sintering step. The temperature is set to rise from room temperature to 900℃ at a rate of 5℃ / min. Then, it is calcined at 900℃ for 8 hours. After cooling, it is ground to obtain the final sample.

[0089] Upon testing, the phase structure of the sample in this embodiment is as follows: Figure 1 As shown in the figure, the material is a perovskite oxide.

[0090] The perovskite electrocatalyst material SrFe prepared in this embodiment 0.6 Ru 0.4 O 3-δ Electrocatalytic performance such as Figure 4 , 6As shown in Figure 8, the perovskite electrocatalyst material SrFe prepared in this example can be seen from the figure. 0.6 Ru 0.4 O 3-δ It exhibits superior electrocatalytic performance in HER, OER, and ORR. Its impedance results are as follows: Figure 9 As shown, the results demonstrate that the perovskite electrocatalyst material SrFe 0.6 Ru 0.4 O 3-δ It has a relatively small charge transfer rate.

[0091] Comparative Example

[0092] This embodiment provides an undoped Ru SrFeO 3-δ Trifunctional perovskite electrocatalyst material SrFeO 3-δ It is prepared by the following method:

[0093] (1) Weigh 10 mmol of strontium nitrate, 10 mmol of ferric nitrate and 2.2 g of polyvinylpyrrolidone and dissolve them in a mixed solution of 8 mL of deionized water, 4 mL of N,N-dimethylformamide and 28 mL of anhydrous ethanol. Stir magnetically at room temperature for 600 rpm / min for 10 h to obtain a uniformly mixed sol.

[0094] (2) The sol obtained in step (1) was transferred to a vacuum drying oven and dried at 95°C for 14 hours to obtain a yellowish-brown gel precursor.

[0095] (3) The yellowish-brown gel precursor obtained in step (2) was placed in a tube furnace for the first step of sintering. The temperature was programmed to rise from room temperature to 250°C at a rate of 2°C / min. Then, it was calcined at 250°C for 1.5 hours. After cooling, it was ground to obtain a black powder sample.

[0096] (4) The black powder sample obtained in step (3) is placed in a tube furnace for the second sintering step. The temperature is set to rise from room temperature to 850°C at a rate of 2°C / min. Then, it is calcined at 850°C for 5 hours. After cooling, it is ground to obtain the final sample.

[0097] Upon testing, the phase structure of the sample in this embodiment is as follows: Figure 1 As shown in the figure, the material is a perovskite oxide.

[0098] The perovskite electrocatalyst material SrFeO prepared in this embodiment 3-δ The scanning electron microscope (SEM) results are as follows: Figure 2 As shown in the figure, the prepared sample has a nanoparticle structure with a particle size of 10-100 nm.

[0099] The perovskite electrocatalyst material SrFeO prepared in this embodiment 3-δ Electrocatalytic performance such as Figure 4 , 6 As shown in Figure 8, the perovskite electrocatalyst material SrFeO prepared in this example can be seen from the figure. 3-δ It exhibits certain electrocatalytic performance in HER, OER, and ORR. Its impedance results are as follows: Figure 9 As shown, the results indicate that the perovskite electrocatalyst material SrFeO 3-δ It has a greater charge transfer rate.

[0100] Application Example 1

[0101] The HER performance testing method is as follows: a three-electrode system is used, with a glassy carbon electrode coated on the sample as the working electrode, a graphite rod as the counter electrode, and an Hg / HgO electrode as the reference electrode. The electrolyte used is a 1M KOH solution. Nitrogen gas is introduced before the test to saturate the electrolyte with nitrogen, and the scan rate is 10 mV / s.

[0102] Figure 4 The trifunctional perovskite electrocatalyst SrFe prepared in Examples 1, 2, 3, 4, 5, and 6 0.7 Ru 0.3 O 3-δ SrFe 0.8 Ru 0.2 O 3-δ SrFe 0.85 Ru 0.15 O 3-δ SrFe 0.9 Ru 0.1 O 3-δ SrFe 0.95 Ru 0.05 O 3-δ SrFe 0.6 Ru 0.4 O 3-δ Comparative SrFeO 3-δ HER polarization curves in N2-saturated 1M KOH solution at a scan rate of 10 mV / s.

[0103] Depend on Figure 4 It can be seen that the SrFe prepared in Examples 1 and 6 0.7 Ru 0.3 O 3-δ and SrFe 0.6 Ru 0.4 O 3-δ The trifunctional perovskite electrocatalyst material is compared with the SrFe prepared in Examples 2, 3, 4, and 5. 0.8 Ru 0.2 O 3-δ SrFe0.85 Ru 0.15 O 3-δ SrFe 0.9 Ru 0.1 O 3-δ SrFe 0.95 Ru 0.05 O 3-δ Comparative SrFeO 3-δ Trifunctional perovskite electrocatalytic materials exhibit better HER electrocatalytic performance, comparable to commercial Pt / C, and even better than commercial Pt / C at high current densities.

[0104] Application Example 2

[0105] The HER stability test method employed a three-electrode system, using a glassy carbon electrode coated on the sample as the working electrode, a graphite rod as the counter electrode, and an Hg / HgO electrode as the reference electrode. The electrolyte used was a 1M KOH solution. Nitrogen gas was purged before the test to saturate the electrolyte with nitrogen. The test was conducted at -10 mA cm⁻¹. -2 A 24-hour chronopotential measurement experiment was conducted under a constant current density.

[0106] Figure 5 The trifunctional perovskite electrocatalyst material SrFe prepared in Example 1 0.7 Ru 0.3 O 3-δ In a 1 MkOH solution saturated with N2, at a constant current density of -10 mA cm⁻¹ -2 The results of a 24-hour time-potential test were obtained.

[0107] Depend on Figure 5 It can be seen that the SrFe prepared in Example 1 0.7 Ru 0.3 O 3-δ Trifunctional perovskite electrocatalytic materials exhibit excellent HER electrocatalytic stability.

[0108] Application Example 3

[0109] The OER performance testing method is as follows: a three-electrode system is used, with a glassy carbon electrode coated on the sample as the working electrode, a platinum wire as the counter electrode, and an Hg / HgO electrode as the reference electrode. The electrolyte used is a 1M KOH solution. Oxygen is introduced before the test to saturate the electrolyte with oxygen, and the scan rate is 10mV / s.

[0110] Figure 6 The trifunctional perovskite electrocatalyst SrFe prepared in Examples 1, 2, 3, 4, 5, and 6 0.7 Ru 0.3 O 3-δ SrFe 0.8Ru 0.2 O 3-δ SrFe 0.85 Ru 0.15 O 3-δ SrFe 0.9 Ru 0.1 O 3-δ SrFe 0.95 Ru 0.05 O 3-δ SrFe 0.6 Ru 0.4 O 3-δ Comparative SrFeO 3-δ OER polarization curves in O2-saturated 1M KOH solution with a scan rate of 10mV / s.

[0111] Depend on Figure 6 It can be seen that the SrFe prepared in Example 1 0.7 Ru 0.3 O 3-δ The trifunctional perovskite electrocatalyst material is compared with the SrFe prepared in Examples 2, 3, 4, 5, and 6. 0.8 Ru 0.2 O 3-δ SrFe 0.85 Ru 0.15 O 3-δ SrFe 0.9 Ru 0.1 O 3-δ SrFe 0.95 Ru 0.05 O 3-δ SrFe 0.6 Ru 0.4 O 3-δ Comparative SrFeO 3-δ Trifunctional perovskite electrocatalytic materials have better OER electrocatalytic performance.

[0112] Application Example 4

[0113] The OER stability test method is as follows: a three-electrode system is used, with a glassy carbon electrode coated on the sample as the working electrode, a platinum wire as the counter electrode, and a Hg / HgO electrode as the reference electrode. The electrolyte used is a 1M KOH solution. Oxygen is bubbled through the electrolyte before testing to saturate it with oxygen. The test is conducted at 10 mA cm⁻¹. -2 A 24-hour chronopotential measurement experiment was conducted under a constant current density.

[0114] Figure 7 The trifunctional perovskite electrocatalyst material SrFe prepared in Example 1 0.7 Ru 0.3 O 3-δIn an O2-saturated 1 M KOH solution, at a constant current density of 10 mA cm⁻¹ -2 The results of a 24-hour time-potential test were obtained.

[0115] Depend on Figure 7 It can be seen that the SrFe prepared in Example 1 0.7 Ru 0.3 O 3-δ Trifunctional perovskite electrocatalytic materials exhibit excellent OER electrocatalytic stability.

[0116] Application Example 5

[0117] The ORR performance test method is as follows: a three-electrode system is used, with a glassy carbon electrode coated on the sample as the working electrode, a platinum wire as the counter electrode, and a Hg / HgO electrode as the reference electrode. The electrolyte used is a 0.1M KOH solution. Oxygen is introduced before the test to saturate the electrolyte with oxygen. The scan rate is 10mV / s.

[0118] Figure 8 The trifunctional perovskite electrocatalyst SrFe prepared in Examples 1, 2, 3, 4, 5, and 6 0.7 Ru 0.3 O 3-δ SrFe 0.8 Ru 0.2 O 3-δ SrFe 0.85 Ru 0.15 O 3-δ SrFe 0.9 Ru 0.1 O 3-δ SrFe 0.95 Ru 0.05 O 3-δ SrFe 0.6 Ru 0.4 O 3-δ Comparative SrFeO 3-δ ORR polarization curves in O2-saturated 0.1M KOH solution with a scan rate of 10mV / s.

[0119] Depend on Figure 8 It can be seen that the SrFe prepared in Example 5 0.95 Ru 0.05 O 3-δ The trifunctional perovskite electrocatalyst material is compared with the SrFe prepared in Examples 1, 2, 3, 4, and 6. 0.7 Ru 0.3 O 3-δ SrFe 0.8 Ru 0.2 O 3-δ SrFe 0.85 Ru0.15 O 3-δ SrFe 0.9 Ru 0.1 O 3-δ SrFe 0.6 Ru 0.4 O 3-δ Comparative SrFeO 3-δ Trifunctional perovskite electrocatalytic materials exhibit better ORR catalytic performance.

[0120] Application Example 6

[0121] The impedance performance test method is as follows: a three-electrode system is used, with the glassy carbon electrode coated on the sample as the working electrode, the platinum wire as the counter electrode, and the Hg / HgO electrode as the reference electrode. The electrolyte used is 1M KOH solution.

[0122] Figure 9 The trifunctional perovskite electrocatalyst SrFe prepared in Examples 1, 2, 3, 4, 5, and 6 0.7 Ru 0.3 O 3-δ SrFe 0.8 Ru 0.2 O 3-δ SrFe 0.85 Ru 0.15 O 3-δ SrFe 0.9 Ru 0.1 O 3-δ SrFe 0.95 Ru 0.05 O 3-δ SrFe 0.6 Ru 0.4 O 3-δ Comparative SrFeO 3-δ Impedance diagram measured in 1M KOH solution.

[0123] Depend on Figure 9 It can be seen that the SrFe prepared in Examples 1 and 6 0.7 Ru 0.3 O 3-δ and SrFe 0.6 Ru 0.4 O 3-δ The trifunctional perovskite electrocatalyst material is compared with the SrFe prepared in Examples 2, 3, 4, and 5. 0.8 Ru 0.2 O 3-δ SrFe 0.85 Ru 0.15 O 3-δ SrFe 0.9 Ru 0.1 O 3-δSrFe 0.95 Ru 0.05 O 3-δ Comparative SrFeO 3-δ Trifunctional perovskite electrocatalytic materials exhibit faster charge transfer rates.

[0124] Application Example 7

[0125] The test method for water electrolysis performance is as follows: a two-electrode system is used, with the nickel mesh coated on the sample as the working electrode, the platinum wire as the counter electrode, and the Hg / HgO electrode as the reference electrode. The electrolyte used is 1M KOH solution, and the scan rate is 10mV / s.

[0126] Figure 10 The SrFe prepared in Example 1 0.7 Ru 0.3 O 3-δ The polarization curves of a trifunctional perovskite electrocatalyst material as the cathode and anode of a dual-electrode system, and a dual-electrode system composed of commercial Pt / C and commercial RuO2, in 1M KOH solution at a scan rate of 10mV / s.

[0127] Depend on Figure 10 It can be seen that the SrFe prepared in Example 1 0.7 Ru 0.3 O 3-δ A dual-electrode system composed of trifunctional perovskite electrocatalytic materials exhibits better water electrolysis performance than a dual-electrode system composed of commercial Pt / C and commercial RuO2.

[0128] Application Example 8

[0129] The method for testing the stability of electrolyzed water is as follows: a two-electrode system is used, with a nickel mesh coated on the sample as the working electrode, a platinum wire as the counter electrode, and an Hg / HgO electrode as the reference electrode. The electrolyte used is 1M KOH solution.

[0130] Figure 11 The SrFe prepared in Example 1 0.7 Ru 0.3 O 3-δ Stability test figures of a two-electrode system composed of a trifunctional perovskite electrocatalytic material and a two-electrode system composed of commercial Pt / C and commercial RuO2 in 1M KOH solution.

[0131] Depend on Figure 11 It can be seen that the SrFe prepared in Example 1 0.7 Ru 0.3 O 3-δ The dual-electrode system composed of trifunctional perovskite electrocatalytic materials exhibits better stability than the dual-electrode system composed of commercial Pt / C and commercial RuO2.

[0132] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions claimed by the present invention.

Claims

1. A Ru-doped SrFeO 3-δ The trifunctional perovskite electrocatalytic material is characterized by... The material is SrFe 1- x Ru x O 3-δ Perovskite oxide, x: 0.05–0.40; microstructure is a nanoparticle structure, the particle size of the nanoparticles is 10–100 nm; the material belongs to the tetragonal crystal system; The overpotential of the perovskite material HER is 40–180 mV vs. RHE, the overpotential of OER is 330–370 mV vs. RHE, and the half-wave potential of ORR is 0.58–0.63 V vs. RHE.

2. The Ru-doped SrFeO according to claim 1 3-δ The trifunctional perovskite electrocatalytic material is characterized by... The x is 0.3, 0.4, or 0.

05.

3. The Ru-doped SrFeO as described in claim 1 3-δ The method for preparing trifunctional perovskite electrocatalytic materials is characterized by... Includes the following steps: (1) Strontium nitrate, ferric nitrate and ruthenium dioxide are mixed with polyvinylpyrrolidone at room temperature, and then deionized water, nitric acid, N,N-dimethylformamide and anhydrous ethanol are added and stirred until uniform to obtain a sol; (2) The sol described in step (1) is dried under vacuum to obtain a gel; (3) The gel described in step (2) is subjected to two-step sintering. The first sintering temperature is 200-350℃, and the second sintering temperature is 750-900℃, to obtain the Ru-doped SrFeO. 3-δ Trifunctional perovskite electrocatalytic materials.

4. The Ru-doped SrFeO according to claim 3 3-δ The method for preparing trifunctional perovskite electrocatalytic materials is characterized by... The molar ratio of strontium nitrate, ferric nitrate and ruthenium dioxide in step (1) is 10:(6-10):(0-4).

5. The Ru-doped SrFeO according to claim 3 3-δ The method for preparing trifunctional perovskite electrocatalytic materials is characterized by... The mass ratio of strontium nitrate and polyvinylpyrrolidone mentioned in step (1) is (0.96-1.33):

1.

6. The Ru-doped SrFeO according to claim 3 3-δ The method for preparing trifunctional perovskite electrocatalytic materials is characterized by... The volume ratio of deionized water, nitric acid, N,N-dimethylformamide and anhydrous ethanol in step (1) is 2:(0-0.3):1:(3-9).

7. The Ru-doped SrFeO according to claim 3 3-δ The method for preparing trifunctional perovskite electrocatalytic materials is characterized by... The stirring time in step (1) is 8-10 hours and the stirring speed is 600 rpm / min.

8. The Ru-doped SrFeO according to claim 3 3-δ The method for preparing trifunctional perovskite electrocatalytic materials is characterized by... The drying temperature in step (2) is 80-100℃ and the drying time is 12-14h.

9. The Ru-doped SrFeO according to claim 3 3-δ The method for preparing trifunctional perovskite electrocatalytic materials is characterized by... The first sintering step (3) involves heating from room temperature to 200-350℃ at a rate of 2-5℃ / min for 1-2 hours, followed by cooling and grinding. The second sintering step involves heating from room temperature to 750-900℃ at a rate of 2-5℃ / min for 5-8 hours.

10. The Ru-doped SrFeO as described in claim 1 3-δ Applications of trifunctional perovskite electrocatalytic materials in water electrolysis, fuel cell technology, and metal-air battery technology.

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