KR102077195B1 - Bifunctional electrocatalyst comprising manganese-iron nanocomposites for oxygen reduction and oxygen evolution, and method of manufacturing the same - Google Patents

Abstract

The present invention relates to a dual functional electrode catalyst for oxygen reduction and oxygen generation and a method for producing the same, comprising a porous structure including Mn-Fe alloy catalyst particles, in the porous structure, the content of Fe is the porous structure It provides a dual functional electrode catalyst for oxygen reduction and oxygen generation is 60 to 70% by weight relative to the total weight of.

Description

Bifunctional electrocatalyst comprising manganese-iron nanocomposites for oxygen reduction and oxygen evolution, and method of manufacturing the same

TECHNICAL FIELD The present invention relates to an electrode catalyst comprising a nanocomposite of manganese-iron and a method for producing the same, and more particularly, to a dual functional electrode catalyst and a method for producing the same, which can be used for both an oxygen reduction reaction and an oxygen generation reaction.

As energy demands increase, research into alternative high-efficiency, low-cost and eco-friendly alternative energy conversion and storage systems is active. In particular, the use of renewable energy to electrochemically think of hydrogen using electrolysis of water has been studied extensively, where the hydrogen produced can be used in fuel cells or direct combustion engines.

Since the electrolysis of water is considered to be an environmentally friendly and economical method of supplying sustainable hydrogen, the development of more effective and stable catalytic electrode material is therefore considered very important. The electrolysis of water can be divided into two half-cell reactions, one of which is the hydrogen evolution reaction (HER) in the cathode and the other is the oxygen evolution reaction in the anode. ; OER). The development of efficient and stable catalysts for oxygen generating reactions that are more complex and require more overvoltage on the mechanism of hydrogen generation is very important for the commercialization of hydrogen production through the electrolysis of large scale water. Precious metal oxide catalysts, including ruthenium (Ru) or iridium (Ir), exhibit high activity, but large scale applications are difficult because of their high cost and scarcity.

Meanwhile, research on electrode catalyst materials to replace platinum (Pt) is continuously required in the fuel cell field. In particular, the fuel cell oxygen catalyst for the oxygen reduction reaction (ORR) is considered to be one of the most important research areas, since it is mainly reduced by the sluggish oxygen reduction reaction (ORR) requiring high overvoltage in the fuel cell cathode. have. Currently, platinum or platinum based electrode catalysts are most widely used as cathode catalysts in fuel cells due to their high activity against ORR, but due to the high cost and limited supply of platinum, they do not contain low amounts of platinum-based or platinum There is a need for efficient alternative catalyst development.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a non-noble metal-based dual functional electrode catalyst which can be used in both an oxygen reduction reaction and an oxygen generation reaction and is capable of mass production.

The problem to be solved by the present invention is not limited to the above-mentioned problem, another task that is not mentioned will be clearly understood by those skilled in the art from the following description.

Including a porous structure including Mn-Fe alloy catalyst particles according to an embodiment of the present invention for achieving the above object, in the porous structure, the content of Fe is 60 to 70% by weight relative to the total weight of the porous structure to be.

According to one embodiment, in the porous structure, the weight ratio of Mn to Fe may be 1: 1.5 to 2.3.

According to one embodiment, the average particle diameter of the alloy catalyst particles may be 20 to 200nm.

According to an embodiment, the Mn-Fe alloy catalyst particles may be connected to each other in a chain structure, and the Mn-Fe alloy catalyst particles connected to the chain structure may form a plurality of pores.

According to one aspect of the present invention, there is provided a method for preparing a dual functional electrode catalyst for reducing oxygen and generating oxygen, according to an embodiment of the present invention, adding a manganese precursor and an iron precursor to an organic solvent, and stirring the reaction solution. Manufacturing step; (b) heating the reaction solution to a temperature of 180 to 250 ° C; (c) cooling the reaction solution to room temperature and washing it; (d) separating and drying the product formed in step (b) from the solution washed in step (c) to obtain a preliminary Mn-Fe alloy catalyst; And (e) heat-treating the preliminary Mn-Fe alloy catalyst at a temperature of 500 to 800 ° C. to form a Mn-Fe alloy catalyst, wherein the Mn-Fe alloy catalyst has Mn-Fe in the form of nanoparticles. Alloy catalyst particles.

According to an embodiment, the Mn-Fe alloy catalyst particles may be connected to each other in a chain structure, and the Mn-Fe alloy catalyst particles connected to the chain structure may form a plurality of pores.

According to one embodiment, in the step (b), the heating of the reaction solution is carried out for 5 to 7 hours, during the heating of the reaction solution may be purged with nitrogen.

According to one embodiment, the organic solvent may include oleylamine.

In some embodiments, the manganese precursor may include potassium permanganate (KMnO ₄ ), and the iron precursor may include iron (III) chloride (FeCl ₃ ).

According to embodiments of the present invention, it is possible to control the shape and size of the Mn-Fe alloy catalyst particles obtained by adjusting the content of the precursor, the reaction temperature, and the reaction time. In particular, by controlling the content of the manganese precursor and the iron precursor (for example, the weight ratio of Mn to Fe) added to the reaction solution, it is possible to easily prepare a Mn-Fe alloy catalyst having a nanoparticle form. In addition, the present invention can be easily scaled up for mass production of the alloy catalyst particles, because the alloy catalyst particles can be produced by a simple method of reacting a reaction solution obtained by dissolving a non-noble metal precursor in an organic solvent for a predetermined time at a constant reaction temperature. can be scale-up.

As a result, it may be possible to provide a non-noble metal-based bi-functional electrode catalyst that can be used for both an oxygen reduction reaction and an oxygen generation reaction, and that can produce a large size.

1 is a flowchart illustrating a method for preparing a dual functional electrode catalyst for reducing oxygen and generating oxygen according to embodiments of the present invention.
Figure 2 shows the XRD measurement results for the Mn-Fe alloy catalysts according to Preparation Examples 1-5.
3 shows SEM images of Mn-Fe alloy catalysts measured prior to heat treatment.
4 shows SEM images of Mn-Fe alloy catalysts measured after heat treatment.
FIG. 5 shows a TEM image for a Mn-Fe alloy catalyst obtained according to Preparation Example 4. FIG.
6 is a GC loaded with Mn-Fe catalyst alloys according to Preparations 1-5, recorded in 0.1 M NaOH solution saturated with oxygen (O ₂ ) at a scan rate of 10 mV / s (rotation speed = 1600 rpm) The RDE polarization curve of the glassy electrode is shown.
FIG. 7 shows the RDE polarization curve of a GC electrode loaded with Mn-Fe catalyst alloys according to Preparations 1-5, recorded in 0.1 M NaOH solution at a scan rate of 10 mV / s (rotational speed = 1600 rpm).

Advantages and features of the present invention, and methods for achieving them will be apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms. It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, 'comprises' and / or 'comprising' refers to a component, step, operation and / or element that is mentioned in the presence of one or more other components, steps, operations and / or elements. Or does not exclude additions.

Hereinafter, embodiments of the present invention will be described in detail.

The electrode catalyst according to embodiments of the present invention may include manganese-iron nanocomposites as a dual functional electrode catalyst. The manganese-iron nanocomposite may be provided as a porous structure including an alloy catalyst of manganese (Mn) and iron (Fe) (hereinafter referred to as Mn-Fe alloy catalyst). In the present specification, the dual functional electrode catalyst may refer to an electrode catalyst that can be used for both an oxygen reduction reaction (ORR) and an oxygen evolution reaction (ORER). For example, the electrode catalyst according to the embodiments of the present invention can be used for the oxygen reduction reaction occurring in the cathode of the fuel cell and can also have the catalytic activity available for the oxygen generation reaction of water electrolysis. Hereinafter, the electrode catalyst according to the embodiments of the present invention is referred to as a dual functional electrode catalyst for oxygen reduction and oxygen generation.

According to the concept of the present invention, the iron content in the porous structure may be 60 to 70% by weight relative to the total weight of the porous structure. In another aspect, in the total weight of the porous structure, the weight ratio of manganese to iron may be about 1: 1.5 to 2.3. When the iron content is less than 60% by weight of the total weight of the porous structure, the Mn-Fe alloy catalyst may have the shape of nanowires or nanorods, and when the iron content exceeds 70% by weight. The Mn-Fe alloy catalyst may have a shape of a dendritic structure. In such a case, the specific surface area of the electrode catalyst may be reduced, thereby lowering the catalytic activity.

In the present invention, as the manganese and iron of the porous structure has a weight ratio as described above, the Mn-Fe alloy catalyst may be provided in the form of nanoparticles. Hereinafter, the Mn-Fe alloy catalyst in the form of nanoparticles may be referred to as Mn-Fe alloy catalyst particles. Mn-Fe alloy catalyst particles may have an average particle diameter of, for example, 20 to 200 nm. If the average particle diameter of the Mn-Fe alloy catalyst particles is smaller than 20 mm, the particles tend to aggregate easily, and if the average particle diameter is larger than 200 nm, the specific surface area becomes small, which may lower the catalyst activity. In addition, the Mn-Fe alloy catalyst particles may be connected to each other in a chain structure to form a plurality of pores. That is, the porous structure may include a plurality of pores defined by Mn-Fe alloy catalyst particles and Mn-Fe alloy catalyst particles connected in a chain structure. The pore size is non-uniform, so that the specific surface area can be further increased.

According to one embodiment, the dual functional electrode catalyst for oxygen reduction and oxygen generation may further include a carbon-based support for fixing the porous structure. In the present invention, the carbon-based support is not particularly limited, and may be a carbon structure having secured conductivity. For example, the carbon-based support may include one or more selected from the group consisting of carbon black, ketjen black (KB), acetylene black, activated carbon powder, carbon molecules, carbon nanotubes, activated carbon having fine pores, and mesoporous carbon. have.

The dual functional electrode catalyst for reducing oxygen and generating oxygen according to an embodiment of the present invention may be increased in resistance to alcohol, but is not limited thereto. For example, when alcohol (for example, methanol or ethanol) is used as fuel in a fuel cell, the alcohol may react at the anode, which is the anode, and the reaction product may be transferred to the cathode, which is the oxygen cathode. Because of the reaction with the product, a voltage drop of the entire fuel cell occurs, which may reduce the efficiency of the fuel cell. However, the electrode catalyst including the Mn-Fe alloy catalyst particles of the present application can maintain the efficiency of the fuel cell by minimizing the reaction with alcohol.

Hereinafter, the manufacturing method of the dual functional electrode catalyst for oxygen reduction and oxygen generation mentioned above is demonstrated. 1 is a flowchart illustrating a method for preparing a dual functional electrode catalyst for reducing oxygen and generating oxygen according to embodiments of the present invention.

Referring to FIG. 1, a manganese precursor and an iron precursor are added to an organic solvent, and the reaction solution may be prepared by stirring (S110). The manganese precursor and the iron precursor may be provided as a material having high solubility in the organic solvent used. For example, the manganese precursor may comprise potassium permanganate (KMnO ₄ ), and the iron precursor may comprise iron (III) chloride (FeCl ₃ ). However, embodiments of the present invention are not limited thereto.

The organic solvent may be provided as a material capable of high temperature synthesis in addition to promoting the reduction reaction of the metal precursor. For example, the organic solvent may be provided as an amine solvent including an alkyl group having 4 to 18 carbon atoms. Preferably, the amine solvent may include butyl amine (butylamine), octyl amine (octylamine), dodecyl amine (dodecylamine) or oleyl amine (Oleylamine). More preferably, oleylamine may be used as the organic solvent. Oleyl amine is an amine of oleic acid, a fatty acid, and because of its relatively high molecular weight, it can form a layer on the surface of the reduced metal. As a result, oxidative stability of the metal particles can be increased by preventing external oxygen from diffusing into the metal particles. Olein amines can also facilitate the dispersion of metal particles in organic solvents.

Subsequently, the reaction solution may be heated to a first temperature (S120). The first temperature is required to be high enough to accelerate the reduction reaction of the metal precursors and to allow the reduced metals to bond with one another to form an alloy. For example, the first temperature may be 180 to 250 ° C. Preferably, the first temperature may be 200 ° C. When the first temperature is less than 180 ° C, the reduction reaction may not be performed properly, and thus metal particles may not be easily formed, and when the first temperature is higher than 250 ° C, decomposition and evaporation of constituents of the reaction solution may occur. The reaction can be difficult, and excessively high temperature reactions can also be economically disadvantageous. In addition, the heating of the reaction solution may proceed for 5 to 7 hours. If the heating time of the reaction solution is less than 5 hours, it is difficult to form particles of the required size and amount, and if the heating time exceeds 7 hours, aggregation of particles may occur due to prolonged reaction. In addition, as the heating time (in other words, the reaction time) increases, the overall particle size tends to increase.

On the other hand, during the reaction of the reaction liquid, the reactor may be maintained in a vacuum atmosphere, a reducing atmosphere or an inert gas atmosphere. When the reaction proceeds in the atmosphere, the metal particles may be oxidized. Therefore, it may be desirable to proceed with the reaction while maintaining nitrogen (N ₂ ) purging to control the oxidation of the metal from the atmosphere during the reaction and further aid the reduction of the metal. Metal particles with controlled oxidation may have improved electrical properties. As a result, the reduced manganese (Mn) and iron (Fe) from each precursor during the step (S120) can be combined to produce preliminary Mn-Fe alloy catalyst particles.

After completion of the reaction, the reaction solution can be cooled to room temperature and washed (S130). The washing of the reaction solution may use ethanol, but is not limited thereto. The washing of the reaction solution may proceed a plurality of times. The product is separated from the washed solution and dried to obtain preliminary Mn-Fe alloy particles (S140). Separation of the product proceeds using centrifugal separation, and the separated product can be dried in a vacuum for 12 to 24 hours.

The obtained product (ie, preliminary Mn-Fe alloy catalyst particles) may be heat-treated at a second temperature (S150). The second temperature may be, for example, 500 to 800 ° C., and the heat treatment may be performed for 4 to 6 hours. Through the heat treatment at the second temperature, the particle stability and properties are improved from the preliminary Mn-Fe alloy particles, the specific surface area is increased, and the desired Mn-Fe alloy catalyst particles can be finally obtained. The Mn-Fe alloy catalyst particles thus obtained may have an average particle diameter of 20 to 200 nm, and may be connected to each other in a chain structure to form a plurality of pores.

According to embodiments of the present invention, it is possible to control the shape and size of the Mn-Fe alloy catalyst particles obtained by adjusting the content of the precursor, the reaction temperature, and the reaction time. In particular, by controlling the content of the manganese precursor and the iron precursor (for example, the weight ratio of Mn to Fe) added to the reaction solution, it is possible to easily prepare a Mn-Fe alloy catalyst having a nanoparticle form. In addition, the present invention can be easily scaled up for mass production of the alloy catalyst particles, because the alloy catalyst particles can be produced by a simple method of reacting a reaction solution in which a non-noble metal precursor is dissolved in an organic solvent for a predetermined time at a constant reaction temperature. can be scale-up.

Hereinafter, the present invention will be described with reference to the following specific examples, but the present invention is not limited only to the following examples.

<Manufacture example 1>

To 25 mL of oleylamine, 75 mg of potassium permanganate (KMnO ₄ ) and 25 mg of iron (III) chloride (FeCl ₃ ) were added, followed by stirring to prepare a reaction solution. At this time, the reaction solution was purple. The reaction solution was heated to 200 ° C. for 6 hours while purging with nitrogen (N ₂ ) to proceed with the reaction. After 6 hours, upon completion of the reaction, the reaction solution turned black. After that, the reaction solution was cooled to room temperature and washed with ethanol. Washing of the reaction solution was repeated four more times. The washed solution was centrifuged at 3000 rpm for 30 minutes to separate the product from ethanol and dried in vacuo for 12 hours. The product was then heat treated at 700 ° C. for 5 hours to obtain a Mn-Fe alloy catalyst.

<Manufacture example 2>

In Preparation Example 1, a reaction solution was prepared by adding 67 mg of potassium permanganate (KMnO ₄ ) and 33 mg of iron (III) chloride (FeCl ₃ ) to 25 mL of oleylamine to prepare a reaction solution. The Mn-Fe alloy catalyst was obtained by the method.

<Manufacture example 3>

In Preparation Example 1, except that 50 mg of potassium permanganate (KMnO ₄ ) and 50 mg of iron (III) chloride (FeCl ₃ ) were added to 25 mL of oleylamine to prepare a reaction solution. The Mn-Fe alloy catalyst was obtained by the method.

<Manufacture example 4>

In Preparation Example 1, except that 33 mg of potassium permanganate (KMnO ₄ ) and 67 mg of iron (III) chloride (FeCl ₃ ) were added to 25 mL of oleylamine to prepare a reaction solution. The Mn-Fe alloy catalyst was obtained by the method.

Production Example 5

In Preparation Example 1, 25 mL of potassium permanganate (KMnO ₄ ) and 75 mg of iron (III) chloride (FeCl ₃ ) were added to 25 mL of oleylamine to prepare a reaction solution. The Mn-Fe alloy catalyst was obtained by the method.

Experimental Example 1

Figure 2 shows the XRD measurement results for the Mn-Fe alloy catalysts according to Preparation Examples 1-5. For comparative evaluation, XRD results for Mn and Fe are included in FIG. 2. Referring to FIG. 2, in the case of Preparation Example 1 (g) and Preparation Example 2 (e) in which the Fe content is lower than Mn, a peak position similar to the XRD measurement result (f) for Mn is shown, and the Fe content In the case of Preparation Example 3 (a), Preparation Example 4 (c) and Preparation Example 5 (b) higher than Mn, it can be seen that the peak position similar to the XRD measurement result (d) for Fe is shown. . That is, in comparison with the XRD measurement results for Mn or Fe, in view of the fact that the XRD measurement results of the results obtained according to Preparation Examples 1 to 5 had a very slight peak position change, Able to know.

In addition, it can be seen that the peak intensity (peak intnsity) is confirmed for the result of Preparation Example 3 (a). From this, it can be inferred that the catalytic activity of the Mn-Fe alloy catalyst obtained according to Preparation Example 3 was the best.

Experimental Example 2

The Mn-Fe alloy catalysts obtained according to Preparation Examples 1 to 5 were divided into before and after heat treatment and subjected to Scanning Electron Microscope (SEM) imaging. FIG. 3 shows SEM images of Mn-Fe alloy catalysts measured before heat treatment, and FIG. 4 shows SEM images of Mn-Fe alloy catalysts measured after heat treatment. Then, using SEM-EDS, the content ratio of Mn-Fe alloy catalysts obtained according to Preparation Examples 1 to 5 (ie, the weight ratio of Mn to Fe) was analyzed and compared with SEM images of Mn-Fe alloy catalysts. . The results are summarized in Table 1 below.

KMnO ₄ (mg) FeCl ₃ (mg) Mn _x Fe _y (weight ratio) Alloy catalyst mode Preparation Example 1 75 25 Mn _0.61 Fe _0.39 nanorod Preparation Example 2 67 33 Mn _0.55 Fe _0.45 nanorod Preparation Example 3 50 50 Mn _0.37 Fe _0.63 porous nanoparticles Preparation Example 4 33 67 Mn _0.32 Fe _0.68 porous nanoparticles Preparation Example 5 25 75 Mn _0.22 Fe _0.78 dendritic structure

Referring to Table 1, when the weight ratio of Mn to Fe in the finally obtained Mn-Fe alloy catalysts is about 1: 1.5 to 2.3 (in other words, the content of Fe to the total weight of the Mn-Fe alloy catalyst is 60 to 70). It can be seen that the Mn-Fe alloy catalyst has a form of porous nanoparticles (when the wt%). Through this, it is confirmed that by controlling the contents of the manganese precursor and the iron precursor, it is possible to control the form of the Mn-Fe alloy catalyst.

In addition, when comparing the SEM images of FIG. 3 and the SEM images of FIG. 4, it can be seen that the particle stability and particle characteristics of the Mn-Fe alloy catalysts are improved and the specific surface area is increased through heat treatment.

Experimental Example 3

The TEM image of the Mn-Fe alloy catalyst obtained according to Preparation Example 4 was measured to more closely observe the structure of the Mn-Fe alloy catalyst in the form of porous nanoparticles. FIG. 5 shows a TEM image for a Mn-Fe alloy catalyst obtained according to Preparation Example 4. FIG. Referring to Figure 5, it can be seen that the Mn-Fe alloy catalyst particles are connected to each other in a chain structure to form a plurality of pores.

Experimental Example 4

In order to analyze the catalytic activity of Oxygen Reduction Reaction (ORR) of Mn-Fe catalyst alloys according to Preparation Examples 1 to 5, a rotating disk electrode (RDE) experiment was performed. For comparison, ORR activity was evaluated for carbon, carbon-based Mn / C, Fe / C, and commercialized Ir / C catalysts. 6 shows GC loaded with Mn-Fe catalyst alloys according to Preparations 1-5, recorded in 0.1 M NaOH solution saturated with oxygen (O 2) at a scan rate of 10 mV / s (rotation speed = 1600 rpm). glassy carbon) shows the RDE polarization curve of the electrode. Here, Mn _0.61 Fe _0.39 / C, Mn _0.55 Fe _0.45 / C, Mn _0.37 Fe _0.63 / C, Mn _0.32 Fe _0.68 / C, Mn _0.22 Fe _0.78 / C are Mn-Fe alloys according to Preparation Examples 1 to 5, respectively. GC electrode loaded with catalysts. For comparison purposes, the results for carbon, Mn / C, Fe / C, and Ir / C catalysts are included.

Referring to FIG. 6, it can be seen that Mn _0.37 Fe _0.63 / C starts the oxygen reduction at the best current magnitude and the low overpotential for the oxygen reduction reaction. This allows the Mn-Fe alloy catalyst in the form of porous nanopaticles to be reduced in oxygen than the catalyst in which Mn or Fe is used alone, and in other forms (eg, nanorods or dendritic structures). It can be seen that the catalytic activity of the reaction (ORR) is excellent. On the other hand, Mn / C can be seen that the current near 0.0 V is greatly changed due to the instability of the manganese itself.

Experimental Example 5

In order to analyze the catalytic activity of Oxygen Evolution Reaction (OER) of Mn-Fe catalyst alloys according to Preparation Examples 1 to 5, a rotating disk electrode (RDE) experiment was performed. For comparison, OER activity was also evaluated for Mn / C, Fe / C, and commercialized Ir / C catalysts with carbon as a support. FIG. 7 shows RDE polarization of a glassy carbon (GC) electrode loaded with Mn-Fe catalyst alloys according to Preparations 1-5, recorded in 0.1 M NaOH solution at a scan rate of 10 mV / s (rotational speed = 1600 rpm) It shows a curve.

Here, Mn _0.61 Fe _0.39 / C, Mn _0.55 Fe _0.45 / C, Mn _0.37 Fe _0.63 / C, Mn _0.32 Fe _0.68 / C, Mn _0.22 Fe _0.778 / C are Mn- according to Preparation Examples 1-5, respectively. GC electrode loaded with Fe alloy catalysts. For comparison purposes, the results for Mn / C, Fe / C, and Ir / C catalysts were included.

To date, Ir is known as the best oxygen generation reaction catalyst among precious metals. However, referring to FIG. 7, in the case of Mn _0.37 Fe _0.63 / C, the onset potential is superior to Ir / C, and it can be confirmed that the catalyst has a catalytic activity equivalent to that of Ir / C. This allows the Mn-Fe alloy catalyst in the form of porous nanopaticles to be oxygen-producing than the catalyst in which Mn or Fe is used alone and other types of Mn-Fe alloy catalysts (eg, nanorods or dendritic structures). It can be seen that the catalytic activity of (OER) is excellent.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. You will understand that there is. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

Claims (9)

A porous structure comprising Mn-Fe alloy catalyst particles,
In the porous structure, the content of Fe is 60 to 70% by weight relative to the total weight of the porous structure,
The Mn-Fe alloy catalyst particles are connected to each other in a chain structure, the Mn-Fe alloy catalyst particles are connected to the chain structure is a dual functional electrode catalyst for oxygen reduction and oxygen generation to form a plurality of pores. The method of claim 1,
In the porous structure, the weight ratio of Mn to Fe is 1: 1.5 ~ 2.3 dual functional electrode catalyst for oxygen reduction and oxygen generation. The method of claim 1,
The average particle diameter of the alloy catalyst particles is 20 to 200nm dual functional electrode catalyst for oxygen reduction and oxygen generation. delete (a) adding a manganese precursor and an iron precursor to an organic solvent and stirring to prepare a reaction solution;
(b) heating the reaction solution to a temperature of 180 to 250 ° C;
(c) cooling the reaction solution to room temperature and washing it;
(d) separating and drying the product formed in step (b) from the solution washed in step (c) to obtain a preliminary Mn-Fe alloy catalyst; And
(e) heat treating the preliminary Mn-Fe alloy catalyst at a temperature of 500 to 800 ° C. to form an Mn-Fe alloy catalyst,
The Mn-Fe alloy catalyst is a method for producing a dual functional electrode catalyst for oxygen reduction and oxygen generation comprising Mn-Fe alloy catalyst particles having the form of nanoparticles. The method of claim 5, wherein
The Mn-Fe alloy catalyst particles are connected to each other in a chain structure,
The Mn-Fe alloy catalyst particles are connected to the chain structure to form a plurality of pores for the production of a dual functional electrode catalyst for oxygen reduction and oxygen generation. The method of claim 5, wherein
In the step (b), the heating of the reaction solution is carried out for 5 to 7 hours,
A method for producing a dual functional electrode catalyst for oxygen reduction and oxygen generation wherein the reaction solution is purged with nitrogen during heating of the reaction solution. The method of claim 5, wherein
The organic solvent is a method for producing a dual functional electrode catalyst for oxygen reduction and oxygen generation containing oleylamine. The method of claim 5, wherein
The manganese precursor comprises potassium permanganate (KMnO ₄ ), the iron precursor comprises iron (III) chloride (FeCl ₃ ) for the production of oxygen and dual-functional electrode catalyst for oxygen generation.

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