Ru-mn2o3 / mno2 composite material as acidic oer electrocatalyst and preparation method thereof

Abstract

The application discloses a Ru-Mn2O3 / MnO2 composite material as an acidic OER electrocatalyst and a preparation method thereof. The preparation method of the composite material comprises the following steps: using an ultrafast sintering technology, taking prepared MnO2 nano powder as a reaction precursor, and performing calcination treatment to obtain the Mn2O3 / MnO2 composite material; then, the composite material is configured into a uniformly dispersed aqueous solution with hydrated ruthenium chloride, and Ru-Mn2O3 / MnO2 is obtained by using the principle of an electrochemical displacement reaction. The preparation method has the advantages of low raw material cost, mild reaction condition, fast reaction rate, energy saving, environmental protection and the like; in the preparation method, the preparation of the Mn2O3 / MnO2 composite material is controlled by regulating the ultrafast sintering reaction temperature; and the prepared Ru-Mn2O3 / MnO2 composite material as the OER electrocatalyst has a low overpotential for the oxygen evolution reaction under acidic conditions, and has a good application prospect in acidic electrocatalytic oxygen production.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of new energy, and particularly relates to a Ru-Mn2O3 / MnO2 composite material as an acidic OER electrocatalyst and a preparation method thereof. BACKGROUND

[0002] For water decomposition hydrogen production technology, the proton exchange membrane (PEM) method has many advantages. This acidic electrolysis process can adapt to intermittent power supply mode, produce high-purity hydrogen, improve hydrogen production efficiency, does not need alkali treatment, and can be quickly started and stopped to match the volatility of renewable energy.

[0003] However, compared with the hydrogen evolution reaction (HER), the oxygen evolution reaction (OER) needs to undergo a slow four-electron transfer step, so a high overpotential needs to be applied to achieve the required hydrogen production rate. In order to improve the energy conversion efficiency and reduce the cost of hydrogen production, it is urgent to develop an OER catalyst with low cost and excellent catalytic activity and stability, and the acidic reaction medium has more stringent requirements for the activity and corrosion resistance of the catalyst. Although RuO2 shows excellent oxygen evolution catalytic activity, and Ru is relatively low in price among noble metals, it still faces the challenges of serious activity decay and insufficient stability, which restricts the application prospect of this type of catalyst in large-scale commercial water electrolysis hydrogen production. In acidic OER, transition metal oxides with stable chemical properties are used as carriers to anchor single dispersed Ru atoms through metal M-O-Ru bonding, which has lower overpotential and better cycle stability than commercial RuO2. The advantages of single dispersed Ru atoms are as follows: (1) each metal atom can be fully utilized as an active center, maximizing atom utilization; (2) unique low coordination / defect structure and special electronic structure endow it with unique activity; (3) active sites are uniformly dispersed on the surface of the carrier, which maximizes the exposure of active sites and avoids agglomeration; (4) metal-carrier interaction can regulate the charge transfer between metal atoms and the carrier, thereby significantly affecting the reaction activity of the catalyst.

[0004] An ideal carrier material not only needs to meet the higher chemical stability to ensure that the structure is not destroyed or dissolved under electrocatalytic conditions, but also needs to have a high specific surface area and an open atomic structure to achieve high uniform dispersion of doped atoms, and has a strong chemical bonding effect on the doped atoms to fix and stabilize them. In addition, in the acidic OER reaction system, the carrier material should also have certain OER catalytic activity and conductivity, aiming to fully exert the synergistic catalytic effect between single atoms and the carrier. Manganese-based oxides have rich valence states and crystal structures, among which α-MnO2 and β-MnO2 with tunnel structures show considerable electrocatalytic performance in acidic OER, and they can realize the anchoring of Ru atoms through electrochemical oxidation and reduction.

[0005] Most of the current studies on Mn-based oxides as single-atom Ru carriers are relatively single in composition, which to some extent restricts the electronic coupling effect between single-atom active centers and the carrier. Based on the flexible and adjustable characteristics of the ratio of Mn and O in Mn-based oxides, constructing multi-component allotropic Mn-based oxides as carrier materials is expected to optimize the electronic interaction between Ru atoms and Mn-based oxide carriers, and thus enhance the activity and stability of the electrocatalyst. SUMMARY

[0006] The present application aims to overcome the above-mentioned deficiencies existing in the prior art, and provides a Ru-Mn2O3 / MnO2 composite material as an acidic OER electrocatalyst and a preparation method thereof. The allotropic Mn2O3 / MnO2 has a rich heterogeneous structure, which can accelerate the transmission rate of electrons through the built-in electric field generated by the interface, and thus optimize the charge interaction between single-atom Ru and Mn-based oxide carriers, and realize the improvement of OER performance under acidic conditions.

[0007] The object of the present application is achieved by the following technical solutions.

[0008] A Ru-MnO x material as an acidic OER electrocatalyst, wherein the Ru-MnO x material has a nanorod morphology, the nanorod diameter is ~ 250 nm, and the nanorod length is ~ 3 μm; wherein the Ru-MnO x material is any one of Ru-Mn2O3 / MnO2 composite material, Ru-MnO2 or Ru-Mn2O3, wherein the diffraction peak position of the Ru-Mn2O3 / MnO2 composite material is completely consistent with the standard card diffraction peak position of β-MnO2 and Mn2O3, and there is no RuO2 diffraction peak and other impurity peaks; wherein the diffraction peak position of the Ru-MnO2 is completely consistent with the standard card diffraction peak position of β-MnO2; the diffraction peak position of the Ru-Mn2O3 is completely consistent with the standard card diffraction peak position of Mn2O3. And the Ru-MnO x material has no RuO2 diffraction peak and other impurity peaks in the diffraction peak, and the Ru element exists in the form of single dispersion in the Mn-based oxide and does not form RuO2.

[0009] The present application also provides a preparation method of the above-mentioned Ru-MnO x material as an acidic OER electrocatalyst, comprising the following steps:

[0010] Step (1): MnSO4·H2O, (NH4)2S2O8 and Na2SO4·10H2O are mixed into a homogeneous aqueous solution, and reacted in a high-pressure reaction kettle at 140℃ for 12h. After cooling, centrifugation, washing and drying treatment, MnO2 nanopowder is obtained.

[0011] Step (2): The MnO2 nanopowder in step (1) is placed in the center of a 5*13 cm*cm graphite paper, and is folded into three folds along the short edge direction of the graphite paper. The folded graphite paper is fixed on the heating element of the ultrafast sintering furnace, and the sample is placed in the center position between the two heating bodies. In the long pulse heating mode, the heating temperature is set to 500℃-650℃, and the heating time (including the heating and holding stages) is 10min. The heating rate is 1℃ / ms. Different heating temperatures obtain β-MnO2, β-MnO2 / Mn2O3 or Mn2O3 nanorod powder.

[0012] Step (3): The nanorod powder obtained in step (2) is dispersed with RuCl3 in water to form a stable suspension. The reaction is carried out in a water bath at 35℃ for 12h. After centrifugation, washing and drying treatment, a series of Ru-MnO2, Ru-Mn2O3 / MnO2 or Ru-Mn2O3 nanorods are obtained.

[0013] The molar ratio of MnSO4·H2O, (NH4)2S2O8 and Na2SO4·10H2O in step (1) is 1:1:3.

[0014] Preferably, the heating temperature in step (2) is 580-620℃, and β-MnO2 / Mn2O3 nanorod powder is obtained in step (2). Then, Ru-Mn2O3 / MnO2 composite material is obtained in step (3).

[0015] The molar ratio of RuCl3 and MnO x in step (3) is 1:10.

[0016] The application also provides the use of the above Ru-Mn2O3 / MnO2 composite material as an electrode material for an acidic OER working electrode.

[0017] The use mode is as follows: Ru-Mn2O3 / MnO2 composite material is dispersed in a mixed solution of ultrapure water and ethanol with 5wt% Nafion aqueous solution, and the obtained slurry is uniformly coated on the surface of carbon paper. The working electrode for acidic OER electrocatalytic reaction is obtained by infrared lamp irradiation and drying.

[0018] The ratio of the amount of Ru-Mn2O3 / MnO2 composite material to the amount of Nafion aqueous solution is 0.33mg / μL.

[0019] The volume ratio of the ultra-pure water and the ethanol is 37:60.

[0020] The volume ratio of the Nafion aqueous solution and the ethanol is 1:20.

[0021] The loading capacity of the composite material is between 1 and 3.3 mg / cm 2 .

[0022] The application further provides an electrolytic cell for an acidic OER electrocatalytic reaction, which adopts the working electrode, a platinum sheet as a counter electrode, an Ag / AgCl as a reference electrode, and an H2SO4 aqueous solution with pH=0 as an electrolyte.

[0023] The application has the following beneficial effects:

[0024] The preparation method is simple and efficient: the Ru-Mn2O3 / MnO2 composite material is prepared by using the ultrafast sintering technology and the electrochemical displacement reaction, the reaction condition is mild, the reaction rate is fast, the raw material cost is low, and the energy saving and environmental protection are achieved.

[0025] The Ru-Mn2O3 / MnO2 composite material has excellent electrocatalytic performance: the Ru-Mn2O3 / MnO2 composite material prepared by the application can be used as an excellent acidic oxygen ionization electrocatalyst, has a low oxygen evolution reaction overpotential and good stability under acidic conditions, and has a good application prospect in the field of acidic electrocatalytic oxygen production.

[0026] The Ru-Mn2O3 / MnO2 allotrope composite material has a unique heterostructure advantage: the Ru-Mn2O3 / MnO2 allotrope composite material has a rich heterojunction structure, the interface can generate a built-in electric field, accelerate the transmission rate of electrons, optimize the charge interaction between the monodisperse Ru atom-manganese-based oxide carrier, and further improve the overall catalytic activity. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The SEM image of the Ru-MnO2 prepared in the embodiment 1 of the application.

[0028] Figure 2 The XRD spectrum of the Ru-MnO2 prepared in the embodiment 1 of the application.

[0029] Figure 3 The linear voltammetry scanning curve of the Ru-MnO2 prepared in the embodiment 1 of the application as the working electrode material for an OER electrocatalytic reaction.

[0030] Figure 4 The SEM image of the Ru-Mn2O3 / MnO2 prepared in the embodiment 2 of the application.

[0031] Figure 5 XRD pattern of Ru-Mn2O3 / MnO2 prepared for Example 2 of the present application.

[0032] Figure 6 Linear voltammetry scan curve of Ru-Mn2O3 / MnO2 prepared for Example 2 of the present application as working electrode material for OER electrocatalytic reaction.

[0033] Figure 7 SEM image of Ru-Mn2O3 prepared for Example 3 of the present application.

[0034] Figure 8 XRD pattern of Ru-Mn2O3 prepared for Example 3 of the present application.

[0035] Figure 9 Linear voltammetry scan curve of Ru-Mn2O3 prepared for Example 3 of the present application as working electrode material for OER electrocatalytic reaction. DETAILED DESCRIPTION

[0036] In order to make the above objectives and advantages of the present application clear and easy to understand, the technical solutions in the embodiments of the present application will be described in detail below with reference to the accompanying drawings of the embodiments of the present application. However, the present application is not limited to the specific embodiments. The materials, if not specifically stated, can be obtained in a commercial way.

[0037] Example 1

[0038] The Ru-MnO2 material is prepared as follows:

[0039] (1) 2 mmol of MnSO4·H2O, 2 mmol of (NH4)2S2O8 and 6 mmol of Na2SO4·10H2O are weighed and dissolved in 70 mL of deionized water, and then reacted in a high-pressure reaction kettle at 140℃ for 12 h. After cooling, centrifugation, washing and drying treatment, MnO2nanopowder is obtained.

[0040] (2) 30 mg of the MnO2nanopowder is placed in the center of a 5*13 cm*cm graphite paper, and is folded into three folds along the short edge direction of the graphite paper. The folded graphite paper is fixed on the heating element of a super-fast sintering furnace, and the sample is ensured to be placed at the center position between the two heating bodies. In the long pulse heating mode, the heating temperature is set to 500℃, and the heating time (including the heating-up and holding stages) is 10 min, wherein the heating-up rate is 1℃ / ms. The calcined β-MnO2nanorod is obtained.

[0041] (3) 24 mg of the calcined β-MnO2 was ultrasonically dispersed in 20 mL of deionized water to form a stable suspension, which was transferred to a 50 mL single-neck glass flask and stirred in a water bath at 35°C until the temperature was stable. Then 2 mL of 0.01 M RuCl3 aqueous solution was slowly added dropwise into the above suspension, and the reaction time was 12 h. After centrifugation, washing and drying, Ru-MnO2 nanorods were obtained.

[0042] The inventors found in repeated experiments that adjusting the heating temperature in the ultrafast sintering furnace in step (2) resulted in different compositions of the nanorods after calcination. When the heating temperature was 500°C to 580°C, step (2) resulted in pure β-MnO2 nanorods after calcination. When the heating temperature was higher than 580°C and lower than 620°C, step (2) resulted in β-MnO2 / Mn2O3 nanorod powder. When the heating temperature was increased to 620°C to 650°C, step (2) resulted in pure Mn2O3 nanorod powder. These different compositions of nanorod powder obtained after step (2) resulted in Ru-MnO2 nanorods (as in Example 1), Ru-Mn2O3 / MnO2 nanorods (as in Example 2) and Ru-Mn2O3 nanorods (as in Example 3) after completing step (3) as above.

[0043] The SEM image of the Ru-MnO2 prepared in Example 1 is shown in FIG. 1, which shows a nanorod structure with a diameter of about 250 nm and a length of about 3 μm. Figure 1 The XRD pattern of the Ru-MnO2 prepared in Example 1 is shown in FIG. 2. According to the standard card JCPDS #NO. 72-1984, the diffraction peak positions of the prepared Ru-MnO2 nanorods completely matched the diffraction peak positions of the standard card, and there were no RuO2 diffraction peaks and other impurity peaks, indicating that the prepared Ru-MnO2 nanorods had high purity, and the Ru element existed in the form of monodispersion in MnO2 and did not form a RuO2 phase. Figure 2 The Ru-MnO2 material prepared in Example 1 was subjected to OER performance testing under acidic conditions, and the testing method was as follows:

[0044] (1) 10 mg of the Ru-MnO2 material was ultrasonically dispersed in 600 μL of ethanol, 370 μL of ultrapure water and 30 μL of Nafion aqueous solution (5 wt%) to form a stable dispersion slurry.

[0045] (2) The pipette was used to take 50 μL of the slurry each time and evenly spread on the surface of a 1*1.5 cm*cm hydrophilic carbon paper, and the infrared lamp was used for drying. This step was repeated 5 times to ensure that the loading amount of the active material was 2.5 mg.

[0046] ​

[0047] (3) The above prepared electrode sheet is used as the working electrode for the acid OER electrocatalytic reaction, the counter electrode is a platinum sheet, the reference electrode is Ag / AgCl, the electrolyte is a pH = 0 H2SO4 aqueous solution, the test voltage range of the linear voltammetry scan curve is 1.0-1.6 V vs. RHE, and the scanning rate is 5 mV s -1 .

[0048] The test results are shown in Table 1. Figure 3 The overpotential of the Ru-MnO2 material prepared in Example 1 is 290 mV at a current density of 10 mA cm -2 .

[0049] Example 2

[0050] The Ru-Mn2O3 / MnO2 composite material is prepared as follows:

[0051] (1) 2 mmol of MnSO4·H2O, 2 mmol of (NH4)2S2O8 and 6 mmol of Na2SO4·10H2O are weighed and dissolved in 70 mL of deionized water, and the reaction is carried out in a high-pressure reaction kettle at 140°C for 12 h. After cooling, centrifugation, washing and drying treatment, MnO2 nanometer powder is obtained.

[0052] (2) 30 mg of the MnO2 nanometer powder is placed in the center of a 5*13 cm*cm graphite paper, and the graphite paper is folded into three along the short edge direction. The folded graphite paper is fixed on the heating element of the ultrafast sintering furnace, and the sample is placed in the center between the two heating bodies. In the long pulse heating mode, the heating temperature is set to 600°C, and the heating time (including the heating and holding stages) is 10 min, wherein the heating rate is 1°C / ms. β-MnO2 / Mn2O3 nanorod powder is obtained.

[0053] (3) 24 mg of the Mn2O3 / MnO2 nanorod powder is ultrasonically dispersed in 20 mL of deionized water to form a stable suspension, and then transferred to a 50 mL single-neck glass flask. Stirring is carried out in a water bath at 35°C until the temperature is stable. Then 2 mL of 0.01M ruthenium hydrate aqueous solution is taken by a pipette and slowly added to the above suspension. The reaction time is 12 h. After centrifugation, washing and drying treatment, Ru-Mn2O3 / MnO2 nanorods are obtained.

[0054] As shown in Table 2, after the ultrafast sintering calcination treatment, the morphology of the nanometer material is not fragmented, the nanorod diameter is about 250 nm, and the nanorod length is about 3 μm. Figure 4 Figure 5 ​For its corresponding XRD pattern, comparing standard card JCPDS # NO. 72-1984 and JCPDS # NO. 71-0636, the prepared Ru-Mn2O3 / MnO2 nanorod diffraction peak position is completely consistent with the standard card diffraction peak position and no RuO2 diffraction peak and other impurity peaks exist, which shows that the prepared Ru-Mn2O3 / MnO2 nanorod has high purity, and the Ru element exists in the form of monodispersion in the manganese-based oxide, and RuO2 is not formed.

[0055] The prepared Ru-Mn2O3 / MnO2 material is subjected to OER performance test under acidic condition, and the test method is the same as that in Example 1. The test results show that, as shown in Figure 6 , the Ru-Mn2O3 / MnO2 material of the present example has an overpotential of 250 mV at a current density of 10 mA cm-2. -2

[0056] Example 3

[0057] The preparation of Ru-Mn2O3 material is as follows:

[0058] (1) 2 mmol of MnSO4·H2O, 2 mmol of (NH4)2S2O8 and 6 mmol of Na2SO4·10H2O are weighed and dissolved in 70 mL of deionized water, and reacted in a high-pressure reaction kettle at 140°C for 12 h. After cooling, centrifugation, washing and drying treatment, MnO2 nanometer powder is obtained.

[0059] (2) 30 mg of MnO2 nanometer powder is placed in the center of a 5*13 cm*cm graphite paper, and is folded into three folds along the short edge direction of the graphite paper. The folded graphite paper is fixed on the heating element of the ultrafast sintering furnace, and the sample is placed in the center position between the two heating bodies. In the long pulse heating mode, the heating temperature is set to 625°C, and the heating time (including the heating and holding stages) is 5 min, wherein the heating rate is 1 ms. Mn2O3 nanorod powder after calcination treatment is obtained.

[0060] (3) 24 mg of calcined Mn2O3 is ultrasonically dispersed in 20 mL of deionized water to form a stable suspension, and is transferred to a 50 mL single-neck glass flask. Stirring is carried out in a water bath at 35°C until the temperature is stable. Then 2 mL of 0.01M RuCl3 aqueous solution is taken by a pipette and slowly added to the above suspension. The reaction time is 12 h. After centrifugation, washing and drying treatment, Ru-Mn2O3 nanorods are obtained.

[0061] As shown in Figure 7 ​It can be seen that after the ultrafast sintering calcination treatment, the morphology of the nanomaterial is not broken, the diameter of the nanorod is about 250 nm, and the length of the nanorod is about 3 μm. Figure 8 For the corresponding XRD pattern, by comparing with the standard card JCPDS # NO. 71-0636, the diffraction peak position of the prepared Ru-Mn2O3 nanorod is completely consistent with the diffraction peak position of the standard card, and there is no RuO2 diffraction peak and other impurity peaks, which indicates that the prepared Ru-Mn2O3 nanorod has high purity, and the Ru element exists in the form of monodispersion in Mn2O3, and does not form a RuO2 phase.

[0062] The Ru-Mn2O3 material prepared above is subjected to OER performance test under acidic conditions, and the test method is the same as that in Example 1. The test results show that as shown in the figure, the overpotential of the Ru-Mn2O3 material of the present example is 270 mV at a current density of 10 mA cm-2. Figure 9 -2

[0063] The inventors found in the comparative study that the Ru-Mn2O3 / MnO2 composite material prepared in the present application has a lower overpotential and more stable cycle performance when applied to acid OER electrocatalysis compared with Ru-Mn2O3 or Ru-MnO2. As shown in the test results of Examples 1, 2 and 3 above, in Example 2, the Ru-Mn2O3 / MnO2 composite material is subjected to OER performance test under acidic conditions, and the overpotential is 250 mV at a current density of 10 mA cm-2, which has the lowest overpotential compared with Ru-MnO2 of Example 1 and Ru-Mn2O3 of Example 3. This is mainly because the Ru-Mn2O3 / MnO2 composite material contains a rich hetero-interface structure of allotropic composite material, which can generate an internal electric field to accelerate the transmission rate of electrons, optimize the charge interaction between monodispersed Ru atoms and manganese-based oxide carriers, and thus improve the overall catalytic activity. -2

[0064] The above-described examples only describe the preferred embodiments of the present application, and do not limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements to the technical solutions of the present application made by those skilled in the art shall fall within the protection scope determined by the claims of the present application.​​​

Claims

1. Ru-MnO as acidic OER electrocatalyst x Process for the preparation of a material, characterized in that, The Ru-MnO x The material presents nanorod morphology; The Ru-MnO x The material is a Ru-Mn2O3 / MnO2 composite material, and the positions of the diffraction peaks thereof are completely consistent with the positions of the standard card diffraction peaks of β-MnO2 and Mn2O3. and the Ru-MnO x There is no RuO2 diffraction peak in the diffraction peak of the material, and other impurity peaks, Ru element exists in the form of monodispersion in the manganese-based oxide, and RuO2 is not formed. The preparation method comprises the following steps: Step (1), mixing MnSO4·H2O, (NH4)2S2O8 and Na2SO4·10H2O into a uniform aqueous solution, carrying out a hydrothermal reaction in a high-pressure reaction kettle, and after cooling, centrifugation, washing and drying treatment, obtaining MnO2 nanopowder; Step (2), placing the MnO2 nanopowder in step (1) into folded graphite paper, fixing on a heating element of an ultrafast sintering furnace, and placing in the center between two heating bodies, in a long pulse heating mode, setting the heating temperature to 580-620℃, to obtain β-MnO2 / Mn2O3 nanorod powder; Step (3), dispersing the nanorod powder prepared in step (2) and RuCl3 in water to form a stable suspension, carrying out a water bath reaction, centrifugation, washing and drying treatment, to obtain Ru-Mn2O3 / MnO2 nanorods.

2. A Ru-MnOx as an acidic OER electrocatalyst according to claim 1 x Process for the preparation of a material, characterized in that: In step (1), the molar ratio of MnSO4·H2O, (NH4)2S2O8 and Na2SO4·10H2O is 1:1:3, the hydrothermal reaction temperature is 140℃, and the reaction time is 12h; in step (2), the long pulse heating is set to a heating time of 10min, the heating time includes a heating-up and a holding stage, and the heating-up rate is 1℃ / ms.

3. A Ru-MnOx as an acidic OER electrocatalyst according to claim 1 x Process for the preparation of a material, characterized in that: In step (3), the molar ratio of RuCl3 to Mn in the nanorod powder is 1:10, and the water bath reaction is carried out in a 35℃ water bath for 12h.

4. A working electrode for acidic OER electrocatalytic reactions, characterized in that: The Ru-Mn2O3 / MnO2 composite material prepared by the preparation method according to any one of claims 1-3 is used as an electrode material in an acidic OER electrocatalytic reaction working electrode.

5. The working electrode for acidic OER electrocatalytic reaction according to claim 4, wherein: The Ru-Mn2O3 / MnO2 composite material and 5wt% Nafion aqueous solution are dispersed in a mixed solution of ultrapure water and ethanol, the obtained slurry is uniformly coated on the surface of carbon paper after ultrasonic treatment, and infrared lamp irradiation drying is carried out to obtain a working electrode for acidic OER electrocatalytic reaction.

6. The working electrode for acidic OER electrocatalytic reaction according to claim 5, wherein: The ratio of the amount of the Ru-Mn2O3 / MnO2 composite material to the amount of Nafion aqueous solution is 0.33mg / μL; the volume ratio of the amount of ultrapure water to the amount of ethanol is 37:60; and the volume ratio of the amount of Nafion aqueous solution to the amount of ethanol is 1:

20.

7. The working electrode for acidic OER electrocatalytic reaction according to claim 5, characterized in that: The loading amount of the Ru-Mn2O3 / MnO2 composite material on the carbon paper is between 1 and 3.3 mg / cm2. 2 between 1 and 3.3 mg / cm2.

8. An electrolytic cell for acidic OER electrocatalytic reactions, characterized in that, The working electrode according to any one of claims 4-7 is used, the counter electrode is a platinum sheet, the reference electrode is Ag / AgCl, and the electrolyte is an H2SO4 aqueous solution with pH=0.

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