KR102582005B1 - Method for manufacturing a nano-catalyst film including a nano-porous graphene membrane, and a method for manufacturing a nano-catalyst electrode including the same - Google Patents

Abstract

One embodiment of the present invention includes (i) preparing a graphene sheet dispersion; (ii) forming a nanoporous graphene membrane by applying the graphene sheet dispersion on a filtration membrane and vacuum filtering; (iii) forming a catalyst film by applying a catalyst dispersion on the nanoporous graphene membrane and vacuum filtering; and (iv) removing the filtration membrane.
According to the above configuration, regardless of the type of catalyst material, the catalyst can be loaded onto the nanoporous graphene membrane as a support without binding to a conductive material or binder, and even a nano-sized catalyst can be loaded into the nanoporous graphene as a support without loss. It is possible to provide a nano catalyst film manufacturing method that can be loaded onto a membrane and can be easily manufactured in a large area at low cost.

Description

Method for manufacturing a nano catalyst film containing a nano-porous graphene membrane and a method for manufacturing a nano catalyst electrode containing the same THE SAME}

The present invention relates to a method of manufacturing a nano catalyst film containing a nano-porous graphene membrane, and more specifically, to a nano-catalyst film comprising a nano-porous graphene membrane capable of effectively containing any nano catalyst and a nano catalyst contained therein. It relates to a method of manufacturing a catalyst film.

Catalysts are used in many reactions, including hydrogen production reactions.

The active site of the catalyst is located on the surface of the particle, and therefore, the surface area of the catalyst particle must be expanded for efficient utilization of the catalyst. As the size of the catalyst particles decreases, the overall surface area of the catalyst increases. However, depending on the reaction environment, there are often limits to the increase in surface area of catalyst particles.

For example, in a gas phase reaction such as a hydrogen production reaction, the reaction gas passes through a catalyst membrane (filter) and is converted into a product gas. In this case, the catalyst generally does not form a membrane by itself, but is combined with a conductive material and a binder in the support membrane. Since they are used in combination, there is a loss in surface area.

Additionally, existing methods of loading a catalyst onto a support membrane had a high catalyst loss rate as the size of the catalyst decreased to nano-sized, and as a result, the efficiency of the catalytic reaction using it decreased.

Since the material that is generally considered an ideal catalyst is a rare and expensive Pt-based material, the surface area loss that occurs when the catalyst is used together with a conductive material and binder in a support membrane is a problem that must be solved in terms of commercialization of the technology.

In order to solve the above problem, US Patent No. 10689537 (Dispersions of holey graphene materials and applications thereof) provides (1) processing a mixture containing an etchant and a graphene oxide sheet to form a porous graphene oxide sheet and (2) dispersing the porous graphene oxide sheet in a solvent to form a porous graphene oxide dispersion containing the porous graphene oxide sheet, and then (3) treating the porous graphene oxide dispersion under reducing conditions to form a graphene- A method for making a graphene-based material is disclosed comprising obtaining self-assembly of porous graphene oxide sheets into a base material.

However, the technology disclosed in the prior invention has the problem of greatly damaging the high electrical conductivity of graphene itself in the process of reducing graphene after oxidizing it.

Therefore, there is an urgent need to develop technology that minimizes the loss of catalyst surface area while not damaging the unique properties of the catalyst and support.

US Patent No. 10689537

The purpose of the present invention to solve the above problems is to provide a support that can utilize a catalyst without a binder and a method of manufacturing a catalyst film containing the same.

Another object of the present invention is to provide a support that can contain a nano-sized catalyst without loss and a method for manufacturing a nano catalyst film containing the same, since the smaller the size of the catalyst, the better the catalytic properties.

Another object of the present invention is to provide a method for manufacturing a support that is simple, large-area, and low-cost, and a method for manufacturing a nanocatalyst film containing the same.

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the description below. There will be.

In order to achieve the above technical problem, a nano catalyst film manufacturing method according to an embodiment of the present invention includes the steps of: (i) preparing a graphene sheet dispersion; (ii) forming a nanoporous graphene membrane by applying the graphene sheet dispersion on a filtration membrane and vacuum filtering; (iii) forming a catalyst film by applying a catalyst dispersion on the nanoporous graphene membrane and vacuum filtering; and (iv) removing the filtration membrane.

In an embodiment of the present invention, the step of drying the nanoporous graphene membrane in a vacuum between steps (ii) and (iii) may be further included.

In an embodiment of the present invention, the nanoporous graphene membrane may be formed to have a thickness of 10 nm or more and less than 100 nm.

In an embodiment of the present invention, the vacuum filtration of the graphene sheet dispersion in step (ii) may be performed at a rate of 1 ml/min or more and less than 2 ml/min.

In an embodiment of the present invention, the catalyst in step (iii) may include one or more selected from the group of MoS _2, LSCO, and a combination thereof.

In order to achieve the above technical problem, another embodiment of the present invention, a nano catalyst electrode manufacturing method, includes the steps of: (i) preparing a graphene sheet dispersion; (ii) forming a nanoporous graphene membrane by applying the graphene sheet dispersion on a filtration membrane and vacuum filtering; (iii) forming a catalyst film by applying a catalyst dispersion on the nanoporous graphene membrane and vacuum filtering; (iv) removing the filtration membrane; and (v) transferring the catalyst film to an electrode.

In an embodiment of the present invention, the step of drying the nanoporous graphene membrane in a vacuum between steps (ii) and (iii) may be further included.

In an embodiment of the present invention, the nanoporous graphene membrane may be formed to have a thickness of 10 nm or more and less than 100 nm.

In an embodiment of the present invention, the vacuum filtration of the graphene sheet dispersion in step (ii) may be performed at a rate of 1 ml/min or more and less than 2 ml/min.

In an embodiment of the present invention, the catalyst in step (iii) may include one or more selected from the group of MoS _2, LSCO, and a combination thereof.

In order to achieve the above technical problem, another embodiment of the present invention provides a nano catalyst film manufactured according to the nano catalyst film manufacturing method.

In order to achieve the above technical problem, another embodiment of the present invention provides a nano catalyst electrode manufactured according to the nano catalyst electrode manufacturing method.

According to the above configuration, the effect of the present invention is that the catalyst can be loaded onto the nanoporous graphene membrane, which is a support, without being restricted by the type of catalyst material and without binding to a conductive material or binder.

Another effect is that even nano-sized catalysts can be loaded onto the support nanoporous graphene membrane without loss.

Another effect is that it can provide a nano catalyst film manufacturing method that can be easily manufactured in a large area at a low cost.

The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

Figure 1 is a flowchart of a nano catalyst film manufacturing method according to an embodiment of the present invention.
Figure 2 is a flowchart of a nano catalyst electrode manufacturing method according to an embodiment of the present invention.
Figure 3 is a schematic diagram of a nano catalyst electrode manufacturing method according to an embodiment of the present invention.
Figure 4 is an image showing comparison of (a) catalyst loading without a nanoporous graphene membrane and (b) catalyst loading with a nanoporous graphene membrane.
Figure 5 is an SEM image showing a cross section of a nano catalyst film prepared according to an example of the present invention.
Figure 6 shows data comparing the catalyst loading performance of the membranes by measuring the absorbance of the nanocatalyst dispersion itself, AAO membrane, nanoporous graphene membrane-AAO membrane, and nanocatalyst dispersion filtered through carbon paper.
Figure 7 is a linear sweep voltammogram measuring the electrical properties of a nano catalyst film prepared using (a) MoS ₂ and (b) LSCO as a catalyst to measure the performance of the nano catalyst film prepared according to an example of the present invention. .

Hereinafter, the present invention will be described with reference to the attached drawings. However, the present invention may be implemented in various different forms and, therefore, is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts that are not related to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

Throughout the specification, when a part is said to be "connected (connected, contacted, combined)" with another part, this means not only "directly connected" but also "indirectly connected" with another member in between. "Includes cases where it is. Additionally, when a part is said to “include” a certain component, this does not mean that other components are excluded, but that other components can be added, unless specifically stated to the contrary.

The terms used herein are only used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to indicate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

Figure 1 is a flowchart of a nano catalyst film manufacturing method according to an embodiment of the present invention.

When described with reference to Figure 1, a nano catalyst film manufacturing method according to an embodiment of the present invention includes (i) preparing a graphene sheet dispersion (S100); (ii) forming a nano-porous graphene membrane by applying the graphene sheet dispersion on a filtration membrane and vacuum filtering (S200); (iii) forming a catalyst film by applying a catalyst dispersion on the nanoporous graphene membrane and vacuum filtering (S300); and (iv) removing the filtration membrane (S400).

At this time, between steps (ii) (S200) and (iii) (S300), a step (S210) of drying the nanoporous graphene membrane in a vacuum is further included.

In an embodiment of the present invention, in the step (S100) of preparing the graphene sheet dispersion in step (i), graphite can be obtained by electrochemical method in a solvent. For example, in the production example of the present invention, graphite from Sigma Aldrich was electrochemically exfoliated in N,N-dimethylformamide, and as a post-treatment, centrifugation was performed at 4500 rpm for 30 minutes to remove non-exfoliated powder to produce graphene. Got the sheet.

Additionally, the graphene sheet can be prepared by purchasing a commercially available product.

When forming a nanoporous graphene membrane using the graphene sheet, a stable film can be formed even after removing the filtration membrane based on the physical properties of graphene, and the conductivity of the graphene sheet is better than that of the existing nano catalyst film. Since the required bonding between the catalyst and the conductive material is not required, the surface area loss of the catalyst is minimized, and as a result, the nano catalyst film of the present invention has the advantage of showing relatively high catalytic efficiency.

Additionally, the graphene sheet has an advantage in terms of cost. Graphene powder or graphene flakes available on the market cost tens of thousands of won per ton, and the present invention can be said to have a great advantage in terms of commercialization of the technology, as multiple membranes can be manufactured with 1 mg of graphene powder.

In an embodiment of the present invention, the filtration membrane of step (ii) (S200) serves as a substrate or support on which the nanoporous graphene membrane is formed and as a filter, and has a porous structure for this purpose.

A filtration membrane that can perform this role may be, for example, anodic aluminum oxide (AAO).

In an embodiment of the present invention, the graphene sheet dispersion of step (ii) (S200) is applied on the filtration membrane and then formed on the filtration membrane by vacuum filtration.

By using the vacuum filtration method, it does not go through the oxidation and reduction processes adopted in the existing prior art, and therefore forms a nano-porous graphene membrane on the filtration membrane without damaging the high electrical conductivity of graphene itself due to oxidation and reduction. There are advantages to doing this. In addition, using the above filtration method has the advantage of being able to manufacture large areas at low cost and with a simple process.

At this time, vacuum filtration of the graphene sheet dispersion is characterized in that it is performed at a rate of 1 ml/min or more and less than 2 ml/min. Vacuum filtration of the graphene sheet dispersion should be more than 1ml/min to save process time and prevent solution leakage between gaps in the filtration device, and less than 2ml/min to minimize aggregation and ensure the graphene membrane. This is because it is formed, and as a result, it has the advantage of being able to efficiently manufacture a uniform membrane.

At this time, the nanoporous graphene membrane is characterized in that it is formed with a thickness of 10 nm or more and less than 100 nm. The thickness of the nanoporous graphene membrane must be 10 nm or more to be entirely filled with graphene to serve as a support, and less than 100 nm because pores in the graphene membrane remain so that the catalyst solution can be filtered later, resulting in the graphene membrane It has the advantage of being able to adjust the size of the pores depending on the thickness.

As the thickness of the nanoporous graphene membrane increases, the overlap between graphene increases, and the pore size decreases accordingly. In other words, the size of the pores can be adjusted by adjusting the thickness.

Looking at the advantage of being able to load a small catalyst by controlling the pore size through thickness, the catalyst is active on the surface, so the larger the surface area or the less surface area loss, the higher the efficiency. Therefore, there is an advantage that the catalytic efficiency of the nano catalyst film of the present invention increases as the nanoporous graphene membrane can form pores of a smaller size.

Based on the above mechanism, the thickness of the nanoporous graphene membrane is determined by considering the desired pore size and the transmittance of the nanocatalyst film of the present invention. The thickness must be 10 nm or more to load the desired nano-sized catalyst without leakage, and the thickness must be less than 100 nm to exhibit effective transmittance so that the nano catalyst film of the present invention can function as a filtration membrane rather than a blocking membrane.

In an embodiment of the present invention, a step (S210) of drying the nanoporous graphene membrane in vacuum is performed between steps (ii) (S200) and (iii) (S300). The drying step (S210) is performed for the purpose of improving the physical or mechanical quality of the nanoporous graphene membrane and increasing the adhesion between the nanoporous membrane and the filtration membrane in preparation for subsequent processing.

In an embodiment of the present invention, the catalyst in the catalyst film forming step (S300) is not limited to the type of catalyst. The present invention is a method of controlling the size of the pores by adjusting the thickness of the nanoporous graphene membrane, and is a mechanism for physically loading the catalyst, so the size of the catalyst is an issue and is not limited by the type of catalyst.

The catalyst is, for example, MoS ₂ used in HER, It may be La _0.5 Sr _0.5 CoO _3-δ (LSCO) used in OER.

Specifically, in the present invention, experiments were conducted using MoS ₂ , La _0.5 Sr _0.5 CoO _3-δ (LSCO) as a catalyst, and a 10 nm level MoS ₂ , La _0.5 Sr _0.5 CoO _3-δ (LSCO) catalyst was manufactured with a thickness of 150 nm. 100% capture or loading was possible with one nanoporous graphene membrane.

According to the above results, the nanoporous membrane of the present invention has the advantage of excellent catalyst loading and has the advantage that its application is not limited by the type of catalyst.

Therefore, in an embodiment of the present invention, the catalyst of step (iii) (S300) may include one or more selected from MoS _2, LSCO, and a combination thereof.

Next, in an embodiment of the present invention, the catalyst dispersion in the step of forming the catalyst film (S300) is applied on a nanoporous graphene membrane and then vacuum filtered to form the catalyst film. Specific vacuum filtration conditions are determined considering the catalyst.

As the catalyst is loaded onto the nanoporous graphene membrane using the vacuum filtration method, bonding with a binder required in the existing nanocatalyst film is not required. Therefore, the catalyst has the advantage of having a relatively small loss in surface area and, as a result, high catalytic efficiency.

In an embodiment of the present invention, the step of forming the catalyst film (S300) is followed by the step of removing the filtration membrane (S400). The filtration membrane is used to form the nanoporous graphene membrane, and the nanoporous graphene membrane can act as a support as a film, and the filtration membrane has more pores than the nanoporous graphene membrane. Because of its large size, it is eliminated as it cannot perform an additional filter role.

Hereinafter, a method for manufacturing a nano catalyst electrode according to another embodiment of the present invention will be described with reference to the drawings. At this time, configurations that overlap with the nano catalyst film manufacturing method described above should be interpreted in the same way, and overlapping explanations will be omitted.

Figure 2 is a flowchart of a nano catalyst electrode manufacturing method according to an embodiment of the present invention.

Figure 3 is a schematic diagram of a nano catalyst electrode manufacturing method according to an embodiment of the present invention.

2 and 3, the nano catalyst electrode manufacturing method according to an embodiment of the present invention includes (i) preparing a graphene sheet dispersion (S100); (ii) forming a nano-porous graphene membrane by applying the graphene sheet dispersion on a filtration membrane and vacuum filtering (S200); (iii) forming a catalyst film by applying a catalyst dispersion on the nanoporous graphene membrane and vacuum filtering (S300); (iv) removing the filtration membrane (S400); and (v) transferring the catalyst film to the electrode (S500).

At this time, between steps (ii) (S200) and (iii) (S300), a step (S210) of drying the nanoporous graphene membrane in vacuum may be further included.

In an embodiment of the present invention, the electrode in the step (S500) of transferring the catalyst film to an electrode is determined according to the purpose of use of the nano catalyst film, which is an embodiment of the present invention. Specifically, the electrode may be carbon paper. However, it is not limited to this.

In an embodiment of the present invention, similar to the nano catalyst film manufacturing method, the nano porous graphene membrane may be formed to have a thickness of 10 nm or more and less than 100 nm.

In an embodiment of the present invention, like the nano catalyst film manufacturing method, vacuum filtration of the graphene sheet dispersion in step (ii) (S200) may be performed at a rate of 1 ml/min or more and less than 2 ml/min. there is.

In an embodiment of the present invention, like the nano catalyst film manufacturing method, the catalyst in step (iii) (S300) may include one or more selected from MoS _2, LSCO, and a combination thereof.

Next, a nanocatalyst film manufactured according to the nanocatalyst film manufacturing method, which is another embodiment of the present invention, and a nanocatalyst electrode containing the same will be described.

The nanocatalyst film of the present invention is manufactured according to the above manufacturing method and includes a nanoporous graphene membrane and a catalyst positioned on the nanoporous graphene membrane, and the nanocatalyst electrode has the nanocatalyst film positioned on the electrode. It is characterized by:

The nano catalyst film of the present invention and the nano catalyst electrode containing the same minimize the surface area loss of the catalyst by including the catalyst on the membrane without a conductive material or binder, and as a result, the efficiency of the catalyst showing an active reaction on the surface is comparable to that of other catalyst films. It is excellent with a noticeable difference.

The nano catalyst film of the present invention and the nano catalyst electrode containing the same have several advantages because they are not limited by the type of catalyst. Unlike existing catalyst film technology, which requires new materials and manufacturing methods depending on the catalyst, the nano catalyst film of the present invention only needs to change the thickness of the catalyst and the nanoporous graphene membrane depending on the intended use. Therefore, it is highly usable and the cost required is low, making it very economical.

Since the nano catalyst film of the present invention and the nano catalyst electrode containing the same can control the size of the pores by adjusting the thickness of the nano-porous graphene membrane, even very small catalysts can be loaded onto the membrane. Therefore, as the size of the catalyst decreases, the surface area increases and the catalyst efficiency improves.

Experimental Example 1

Comparison experiment of catalyst loading with and without nanoporous graphene membrane

This will be explained with reference to Figure 4.

Figure 4 is an image showing comparison of (a) catalyst loading without a nanoporous graphene membrane and (b) catalyst loading with a nanoporous graphene membrane.

This experiment was performed using MoS ₂ as a catalyst and an anodic aluminum oxide (AAO) membrane as the filtration membrane. Figure 4(a) shows vacuum filtration of MoS ₂ nanocatalyst in a configuration where only an AAO membrane is present. This is the result, and Figure 4(b) is the result of vacuum filtration of the MoS ₂ nanocatalyst in a configuration where a nanoporous graphene membrane is present.

Referring to Figure 4, the amount of nano catalyst remaining after vacuum filtration can be compared. The nanoporous graphene membrane was able to load a significantly larger amount of nanocatalyst than the AAO membrane, and these results are expected to differ more significantly as the size of the nanocatalyst decreases.

Through this experiment, it was confirmed that the nanocatalyst film containing a nanoporous graphene membrane showed excellent properties for loading nanosized catalysts.

Experimental Example 2

Experiment to confirm the mechanical superiority of nanoporous graphene membrane

This will be explained with reference to Figure 5.

Figure 5 is an SEM image showing a cross section of a nano catalyst film prepared according to an example of the present invention.

According to Figure 5, it was confirmed that the nano catalyst film supported by the nano-porous graphene membrane could be separated without damage during the separation process from AAO and transferred to the electrode.

On the other hand, looking at the case where a nano catalyst film formed directly on the AAO membrane without a nano-porous graphene membrane is separated from the AAO membrane (not shown), if the size of the nano catalyst sheet constituting the nano catalyst film does not meet a certain size, it is damaged. This occurred, and even if the size of the nano catalyst sheet was larger than a certain size, the frequency of damage was high when the AAO membrane was separated.

According to the results of this experiment, it is not practical to form a nanocatalyst film with only nanocatalysts, so a support is needed, and since the nanoporous graphene membrane has mechanically robust properties, it can play a sufficient role as a support for the nanocatalyst film. It was confirmed that there was.

Experimental Example 3

Catalyst loading characteristics confirmation experiment

This will be explained with reference to Figure 6.

Figure 6 shows data comparing the catalyst loading performance of the membranes by measuring the absorbance of the nanocatalyst dispersion itself, AAO membrane, nanoporous graphene membrane-AAO membrane, and nanocatalyst dispersion filtered through carbon paper.

This experiment is an experiment that quantitatively analyzes how much nanocatalyst was loaded on the membrane by measuring the concentration of the MoS ₂ dispersion liquid filtered through various membranes.

According to Figure 6, the As-prepared solution showed peaks at 600 nm and 672 nm, confirming that the MoS ₂ nano catalyst sheet was stably dispersed without significant aggregation.

Based on the Beer-Lambert law and the extinction coefficient of the MoS ₂ nanocatalyst sheet dispersion (α ₆₇₂ = 3400 mL/mg m), the concentration of the unfiltered MoS ₂ dispersion (As-prepared) is analyzed to be ~0.003 mg/mL.

Next, the concentration of the MoS ₂ dispersion filtered through the AAO membrane was ~0.0005 mg/mL, which indicates that ~17% of the MoS ₂ nanocatalyst sheet passed through the AAO membrane when the pore size was 25 nm.

Next, the concentration of the MoS ₂ dispersion filtered through the nanoporous graphene membrane-AAO membrane was ~0.0002 mg/mL, which indicates that most of the MoS ₂ nanocatalyst sheets could be collected on the nanoporous graphene membrane. . For reference, since the pore size of the AAO membrane is significantly larger than that of the nanoporous graphene membrane, the amount of nanocatalyst sheets collected on the AAO membrane can be ignored in the above results.

As a comparison group, the results of direct vacuum filtration of the MoS ₂ nano catalyst sheet on carbon paper were also investigated to test the case of directly loading the nano catalyst sheet onto the electrode without the intermediate assembly and transfer steps by the membrane, and a significant amount of MoS ₂ nano catalyst was tested. Because the catalyst sheet (~67%) permeated through the microporous structure of the carbon paper, the concentration was confirmed to decrease from ~0.003 mg/mL to ~0.002 mg/mL after filtration.

The above results confirmed the excellent nanocatalyst loading characteristics of the nanoporous graphene membrane.

Experimental Example 4

Experiment to confirm electrical properties of nano catalyst film

This will be explained with reference to Figure 7.

Figure 7 shows linear sweep voltammograms measuring the electrical properties of a nanocatalyst film prepared using (a) MoS ₂ and (b) LSCO as a catalyst to measure the performance of the nanocatalyst film prepared according to an example of the present invention. .

This experiment compared the properties of nanocatalyst films with the same amount of MoS ₂ to confirm that the difference in activity of MoS ₂ nano catalysts in HER (hydrogen evolution reaction) results from differences in the size or surface area of the catalyst. HER was performed in 1M KOH solution.

According to Figure 7(a), (1) when the electrode was coated with a nanoporous graphene membrane only (GNS only), the current density did not change significantly within the tested potential range, and the onset potential was similar to the size of the MoS ₂ nanocatalyst sheet; Alternatively, it was confirmed that it depends on the surface area. (2) Examining the results of nanocatalyst films composed of S, M, L, E-MoS ₂ nanocatalyst sheets and nanoporous graphene membranes, the onset potential for HER becomes lower as the size of MoS ₂ nanocatalyst sheets decreases. was confirmed. Additionally, since a decrease in the size of the catalyst sheet means an increase in surface area based on the same amount of catalyst, it was confirmed that the initiation potential for HER decreases as the surface area increases.

Likewise, the current characteristics depending on the presence or absence of a nanoporous graphene membrane were confirmed in OER (oxygen evolution reaction).

In this experiment, OER was performed in a 1M KOH solution, and a group in which LSCO nanocatalysts with an average diameter of 135 nm were vacuum filtered directly onto a carbon paper electrode without a membrane were compared with a group formed on a carbon paper electrode including a nanoporous graphene membrane. .

According to Figure 7(b), when the LSCO nanocatalyst was formed on a carbon paper electrode including a nanoporous graphene membrane, a lower onset potential was shown compared to when the LSCO nanocatalyst was formed directly on the electrode, which is consistent with the nanoporous graphene membrane of the present invention. This result confirms that the porous graphene membrane dramatically increases catalyst utilization.

The description of the present invention described above is for illustrative purposes, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. will be. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as single may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the patent claims described below, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention.

Claims (12)

(i) preparing a graphene sheet dispersion;
(ii) forming a nanoporous graphene membrane by applying the graphene sheet dispersion on a filtration membrane and vacuum filtering;
(iii) forming a catalyst film by applying a catalyst dispersion on the nanoporous graphene membrane and vacuum filtering; and
(iv) removing the filtration membrane;
The nano-porous graphene membrane is a nano catalyst film manufacturing method, characterized in that formed with a thickness of 10 nm or more and less than 100 nm. According to paragraph 1,
Characterized in that it further comprises a step of drying the nanoporous graphene membrane in a vacuum between steps (ii) and (iii). delete According to paragraph 1,
Vacuum filtration of the graphene sheet dispersion in step (ii) is performed at a rate of 1 ml/min or more and less than 2 ml/min. According to paragraph 1,
The catalyst in step (iii) is a nano catalyst film manufacturing method, characterized in that it includes at least one selected from the group of MoS _2, LSCO, and a combination thereof. (i) preparing a graphene sheet dispersion;
(ii) forming a nanoporous graphene membrane by applying the graphene sheet dispersion on a filtration membrane and vacuum filtering;
(iii) forming a catalyst film by applying a catalyst dispersion on the nanoporous graphene membrane and vacuum filtering;
(iv) removing the filtration membrane; and
(v) transferring the catalyst film to an electrode,
The nano-porous graphene membrane is a nano-catalyst electrode manufacturing method, characterized in that formed with a thickness of 10 nm or more and less than 100 nm. According to clause 6,
Characterized in that it further comprises a step of drying the nano-porous graphene membrane in a vacuum between steps (ii) and (iii). delete According to clause 6,
A method of manufacturing a nano catalyst electrode, characterized in that the vacuum filtration of the graphene sheet dispersion in step (ii) is performed at a rate of 1 ml/min or more and less than 2 ml/min. According to clause 6,
The catalyst in step (iii) is a nano catalyst electrode manufacturing method, characterized in that it includes at least one selected from the group of MoS _2, LSCO, and a combination thereof. A nano catalyst film manufactured according to the nano catalyst film manufacturing method of claim 1. A nano catalyst electrode manufactured according to the nano catalyst electrode manufacturing method of claim 6.

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