WO2024010287A1 - Carbon support-based porous hydrolysis catalyst and manufacturing method therefor - Google Patents

Abstract

The present invention relates to a carbon support-based porous hydrolysis catalyst and a manufacturing method therefor and, more specifically, to a porous hydrolysis catalyst including a conductive carbon support derived from textile materials, and a manufacturing method therefor. With a porous structure that makes it easy for hydrogen or oxygen generated on the catalyst surface to escape, the porous hydrolysis catalyst including a conductive carbon support derived from textile materials according to the present invention possesses excellent charge transport capabilities, allows for easy penetration of the electrolyte, and exhibits high hydrolysis performance. Moreover, the hydrolysis catalyst manufactured in the present invention maintains low voltage over a long period even at high currents, indicating high operational stability. In addition, the present invention is used for manufacturing hydrolysis catalysts without restrictions on size or shape and thus can be advantageously applied to the manufacture of hydrolysis electrodes.

Description

Carbon support-based porous water decomposition catalyst and method for manufacturing the same

The present invention relates to a porous water decomposition catalyst based on a carbon support and a method for manufacturing the same, and more specifically, to a porous water decomposition catalyst comprising a conductive carbon support derived from a textile material and a method for manufacturing the same.

As industrial development increases, the use of fossil fuels increases and carbon dioxide generation increases, leading to serious environmental problems. Therefore, much research is being conducted around the world to develop energy to replace the use of fossil fuels. In particular, interest in hydrogen energy is increasing as various countries and groups announce hydrogen development roadmaps. Hydrogen is attracting attention as a next-generation energy source because it does not emit toxic gases when used as a fuel and can produce high energy-to-weight ratio. Reforming is the most commonly used method to produce hydrogen, but it has the disadvantage of being carried out under high temperature and pressure and ultimately emitting carbon dioxide to produce hydrogen. On the other hand, the water decomposition method can produce high purity hydrogen without producing by-products, so many researchers are paying attention to efficient water decomposition methods.

The components of the water splitting catalyst can be divided into a hydrogen generation catalyst at the cathode and an oxygen generation catalyst at the anode. Not only the hydrogen generation catalyst but also the oxygen generation catalyst must have high performance in the same electrolyte to reduce the total moisture. High efficiency can be expected. In addition, water decomposes and intermediates repeatedly attach to and fall off the catalyst surface, which represents catalyst activation energy, so providing abundant active sites on the catalyst surface, rapid charge transfer, and driving stability are important factors for efficient hydrogen production. It can be seen that

The metals most commonly used as existing water decomposition catalysts are platinum (Pt) for the cathode and iridium (Ir) and ruthenium (Ru) for the anode. It is used by making it into particles or powder, but since this form cannot be used alone, it is used by blending carbon black and Nafion polymer and dropping it on glassy carbon (GC) (N. Cheng et al . , Nat. Commun., 2016, 7, 13638). The above metals are very expensive, and the low hygroscopicity of carbon black affects the contact area between the electrolyte and the catalytic active site. Nafion, an insulating material, reduces charge transfer, ultimately reducing catalyst efficiency. It falls.

Currently, Ni(OH) ₂ (nickel hydroxide) as a water decomposition catalyst plays the role of breaking the HO-H bond, and Ni is a key material for recombining the decomposed intermediate H _ad into hydrogen after it is adsorbed, and Pt It is known to have similar performance (R. Subbaramn et al. , Science , 2011, 334, 1256). Therefore, research is being actively conducted on the development of a porous catalyst that can realize Ni and Ni(OH) ₂ with high catalytic activity with a high surface area and be used as a stand-alone catalytic electrode without the need for an additional binder.

In previous studies, NiV (Nickel Vanadium) was grown on Ni foam using a hydrothermal method (D. Wang et al. , Nat. Commun. , 2019, 10, 3899), or NiMo-N ( Nickel Molybdenum-Nitride nanoplates were grown directly on carbon fabric cloth using hydrothermal synthesis (F. Yu et al. , Nat. Commun. , 2018, 9, 2551). Furthermore, NiFe-P was grown directly on Ni foam using CVD (chemical vapor deposition) method and used as an electrode for two reactions, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), and cellulose paper filter as an insulator. Ni-P was electroless deposited on top, and NiFe and NiMo were adsorbed on top of it using a three-electrode electroplating method and used as oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) catalysts, respectively ( A. Sahasrabudhe et al. , Nat. Commun ., 2018, 9, 2014).

Materials such as Ni foam have the same conductivity as metal, enabling rapid charge transfer, but the process is very dangerous because pores are formed through an etching process using a strong acid such as HF (hydrogen fluoride). And because the price is quite expensive, there are limitations in producing large-capacity catalysts. In the case of hydrothermal synthesis, expensive equipment is required and it is difficult to uniformly coat the desired metal. Carbon fabric cloth has strong hydrophobic properties as most of its elemental content is made up of carbon, so when used as a support, even if hydrothermal synthesis is used, the catalyst layer is not evenly formed on the fibril strands inside. No. In addition, it is difficult for the metal to grow inside the Ni fibrils made through electroless plating, and it is very difficult to control its thickness consistently. Therefore, even if NiFe and NiMo are grown on top of it by electroplating, the inner Ni-P cannot be grown on the non-stacked fibril strands, so not only is the surface area of the porous structure not fully utilized, agglomeration is observed on the surface, and it is in powder form. Because it is easy to fall, it has limitations in stability.

In addition, in order to use water splitting as a means of industrially generating hydrogen, the water splitting electrode must maintain a low voltage under a high current for a long time (F. Yu et al. , Nat. Commun. , 2018, 9, 2551) . However, in general, water decomposition electrodes generate pressure due to gas generation inside the electrode as hydrogen and oxygen are generated (R. Iwata et al ., Joule , 2021, 5, 887-900), and at this time, the electrode is laminated on the support. This has the limitation that the catalyst layer is desorbed or peeled off, ultimately reducing the stability of the electrode.

In particular, when using the existing water-decomposition metal catalyst by making it into nanoparticles or powder, Nafion polymer is used as described above. This is simply a method of physically coating the electrode support, so it is used on the water-decomposition electrode under a high current. There is a limitation that when a lot of gas is generated, high pressure is generated and it is difficult to operate for a long time. Therefore, research on the development of a porous catalyst that can be used as a stand-alone catalyst electrode without the need for an additional binder is required.

Accordingly, the present inventors have made diligent efforts to solve the problems of the water-decomposing electrode, and as a result, a uniform and stable metal coating has been applied to an insulating fabric material through a simple plating method through an interface design based on a carbonization process and hydrogen bonding, resulting in a high A water decomposition catalyst with catalytic performance and excellent stability was manufactured, and the present invention was completed.

Therefore, the object of the present invention relates to a porous water decomposition catalyst comprising a conductive carbon support derived from a textile material and a method for producing the same.

To achieve the above-mentioned purpose,

The present invention provides a conductive carbon support derived from a textile material;

It includes a catalytically active layer formed on the conductive carbon support,

The conductive carbon support provides a hydrophilic porous water decomposition catalyst.

In a preferred embodiment of the present invention, the conductive carbon support derived from a fabric material may be a conductive carbon support formed through carbonization by heat treatment of a fabric material.

In another preferred embodiment of the present invention, the fabric material may include any one or more selected from the group consisting of cotton fibers, silk fibers, cellulose, polyester, nylon, acrylic fibers, and polyacrylonitrile fibers. there is.

In another preferred embodiment of the present invention, the sheet resistance of the carbon support may be 10 ⁰ to 10 ⁴ Ω/sq.

In another preferred embodiment of the present invention, the conductive carbon support derived from a textile material may have its surface modified with a thiol group (-SH), a carboxyl group (-COOH), or an amine group (-NH ₂ ).

In another preferred embodiment of the present invention, the catalytically active layer may include a catalyst metal layer and a hydroxide layer or oxyhydroxide layer formed on the catalyst metal layer.

In another preferred embodiment of the present invention, the catalyst metal layer is nickel (Ni), cobalt (Co), iron (Fe), molybdenum (Mo), copper (Cu), vanadium (V), and tungsten (W ) may include any one or more selected from the group consisting of.

In another preferred embodiment of the present invention, the hydroxide layer includes Ni(OH) ₂ , and the beta phase of Ni(OH) ₂ may be dominant over the alpha phase.

In another preferred embodiment of the present invention, if the catalytic active layer of the porous water decomposition catalyst includes a hydroxide layer, it is a hydrogen generation reaction water decomposition catalyst,

If the catalytically active layer includes an oxyhydroxide layer, it may be an oxygen generation reaction water decomposition catalyst.

Additionally, the present invention provides a porous water decomposition electrode including the porous water decomposition catalyst.

In addition, the present invention includes the steps of (a) carbonizing a fabric material by heat treatment to form a conductive carbon support; and

(b) electroplating the carbon support with a catalytic metal to coat a catalytically active layer,

The carbon support formed in step (a) is hydrophilic, providing a method for producing a porous water decomposition catalyst.

In a preferred embodiment of the present invention, the textile material may include any one or more selected from the group consisting of cellulose, polyester, nylon, acrylic fiber, and polyacrylonitrile fiber.

In another preferred embodiment of the present invention, the heat treatment in step (a) may be performed at 600 to 1000°C.

In another preferred embodiment of the present invention, step (a) further includes modifying the surface of the carbon support with a thiol group (-SH), carboxyl group (-COOH), or amine group (-NH ₂ ). It can be included.

In another preferred embodiment of the present invention, the catalyst metal in step (b) is nickel (Ni), cobalt (Co), iron (Fe), molybdenum (Mo), copper (Cu), and vanadium (V). , and may include any one or more selected from the group consisting of tungsten (W).

In another preferred embodiment of the present invention, when the catalyst metal in step (b) is nickel (Ni), a porous water decomposition catalyst for hydrogen generation reaction in which a hydroxide layer containing Ni (OH) ₂ is formed is prepared. The beta phase of Ni(OH) ₂ may be dominant over the alpha phase.

In another preferred embodiment of the present invention, when the catalyst metal in step (b) contains two or more selected from the group consisting of nickel (Ni), cobalt (Co), and iron (Fe), NiOOH is included. An oxygen generation reaction porous water decomposition catalyst having an oxyhydroxide layer formed can be manufactured.

In another preferred embodiment of the present invention, the oxyhydroxide layer containing NiOOH is formed by forming a hydroxide layer containing Ni(OH) ₂ and then forming a hydroxide layer containing nickel (Ni), cobalt (Co), and iron (Fe). An oxygen-generating water decomposition catalyst can be manufactured by secondary plating with two or more metals selected from the group consisting of to form an oxyhydroxide layer containing NiOOH.

The porous water decomposition catalyst comprising a conductive carbon support derived from a textile material according to the present invention has a porous structure so that hydrogen or oxygen generated on the catalyst surface can easily escape, and has excellent charge transport ability, easy penetration of electrolyte, and high water decomposition. It has a performance effect. In addition, the water decomposition catalyst produced in the present invention has high driving stability, capable of maintaining a low voltage for a long time even at high currents, and can be used to manufacture water decomposition electrodes without size or shape restrictions, so it can be usefully used in the manufacture of water decomposition electrodes. You can.

Figure 1 is a schematic diagram showing the manufacturing process of a porous water decomposition catalyst containing a conductive carbon support derived from a textile material of the present invention.

Figure 2 is a diagram comparing the contact angle of a conventional carbon fiber fabric (Carbon fabric cloth) and a carbon support based on a fabric material of the present invention.

Figure 3 is a diagram showing the conductivity and sheet resistance of the carbon support according to the type of fabric material and the temperature at which carbonization occurs.

Figure 4 is a diagram showing a Fourier transform infrared spectroscopy graph (FT-IR) for carboxyl groups and amine groups on the surface of a surface-modified carbon support.

Figure 5 shows the crystal structure shape of Ni(OH) ₂ (A), Ni electroplated porous water splitting catalyst (EP Ni-CST) (B), and Ni electroless plated porous water splitting catalyst (EL Ni-CST) ( C) This is a diagram showing the crystal structure of Ni(OH) ₂ .

Figure 6 is a diagram showing conductivity and sheet resistance according to electroplating time.

Figure 7 is a SEM (Scanning Electron Microscopy) image according to the manufacturing process of the porous water decomposition catalyst of the present invention.

Figure 8 is a scanning electron microscopy (SEM) image of the Ni electroplated porous water decomposition catalyst (A), NiFeCo electroplated porous water decomposition catalyst (B), and commercial Ni foam (C).

Figure 9 is an Energy Dispersive X-Ray Analysis (EDX) image of the Ni electroplated porous water splitting catalyst (A) and Ni electroplated carbon fiber fabric (B) of the present invention.

Figure 10 is an SEM and EDX image of the Ni electroplated porous water decomposition catalyst (A) and Ni electroless plated porous water decomposition catalyst (B) of the present invention.

Figure 11 is an SEM and EDX image of the NiFeCo electroplated porous water decomposition catalyst (A) of the present invention and the NiFeCo porous water decomposition catalyst (B) prepared by hydrothermal synthesis.

Figure 12 shows the NiFeCo electroplated porous water decomposition catalyst (EP NiFeCo-CST) (A) and the NiFeCo porous water decomposition catalyst (Hyd NiFeCo-CST) (B) prepared by hydrothermal synthesis through X-ray diffraction (XRD) analysis. This is a drawing confirming the crystal structure.

Figure 13 is a diagram showing the results of a bending test of the Ni electroplated porous water decomposition catalyst (A) and the NiFeCo electroplated porous water decomposition catalyst (B).

Figure 14 in 1M KOH electrolyte This is a diagram confirming the hydrogen generation performance (A) and overpotential degree (B) of the Ni electroplated porous water decomposition catalyst (hydrogen generation catalyst).

In the above figure, Pt/C/Ni foam represents a commercially sold hydrogen generation electrode, CST represents a carbon support derived from a textile material, EL Ni-CST represents a porous water decomposition catalyst electroless plated with Ni, and EP Ni-CST represents a carbon support derived from a textile material. It refers to the Ni electroplated porous water decomposition catalyst of the invention.

Figure 15 shows the oxygen generation performance (A) of the NiFeCo electroplated porous water decomposition catalyst (oxygen generation catalyst) in 1M KOH electrolyte, the oxygen generation performance (B) according to the type of metal catalyst, and the degree of overvoltage (C) according to the type of metal catalyst. ) is a drawing confirming this.

In Figure 15(A), IrO ₂ /Ni foam is a commercially available oxygen generating electrode, EP Ni-CST is a Ni electroplated porous water decomposition catalyst of the present invention, and Hyd NiFeCo-CST is a hydrothermal synthesis method. NiFeCo porous water decomposition catalyst, EP NiFeCo-CST refers to the NiFeCo electroplated porous water decomposition catalyst of the present invention.

In addition, in Figure 15(B), EP NiFeCo-CST refers to the NiFeCo electroplated porous water decomposition catalyst of the present invention, EP NiFe-CST refers to the NiFe electroplated porous water decomposition catalyst, and EP Ni-CST refers to the Ni Fe electroplated porous water decomposition catalyst of the present invention. It refers to an electroplated porous water decomposition catalyst.

Figure 16 is an image of a two-electrode system connecting the Ni electroplated porous water decomposition catalyst as the cathode and the NiFeCo electroplated porous water decomposition catalyst as the anode [EP Ni(-)∥EP NiFeCo/Ni(+)](A ), Current density performance analysis of the two-electrode system (B) and (C) are diagrams evaluating the electrode efficiency of the two-electrode system.

As a control, a water decomposition electrode [Pt/C(-)∥ ₂ (+)] connected with Pt/C/Ni foam as the cathode and IrO ₂ /Ni foam as the anode, and a porous water decomposition catalyst with Ni electroless plating were used. As a cathode, a water decomposition electrode [EL Ni(-)∥Hyd NiFeCo/Ni(+)] was used, in which a NiFeCo porous water decomposition catalyst prepared by hydrothermal synthesis was connected to the anode.

Figure 17 is a diagram comparing the performance of the water-splitting electrode composed of the two-electrode system of the present invention and other water-splitting electrodes.

Figure 18 is a diagram showing a cell voltage measurement graph according to the current density of the water splitting electrode composed of the two-electrode system of the present invention and SEM images (red box) before and after the electrode reaction.

Figure 19 shows a water splitting electrode [Pt/C(-)∥ ₂ (+)] (A) connecting Pt/C/Ni foam as a cathode and IrO ₂ /Ni foam as an anode, and a porous Ni electroless plated. Cell voltage according to the current density of the water decomposition electrode [EL Ni(-)∥Hyd NiFeCo/Ni(+)](B), which connects the water decomposition catalyst as the cathode and the NiFeCo porous water decomposition catalyst prepared by hydrothermal synthesis as the anode. This is a drawing showing the measurement graph.

Hereinafter, the present invention will be described in detail.

Consistently, the present invention provides a conductive carbon support derived from a textile material;

It includes a catalytically active layer formed on the conductive carbon support,

The conductive carbon support relates to a hydrophilic porous water decomposition catalyst.

In the present invention, the conductive carbon support derived from a fabric material refers to a conductive support formed by heat treatment of a fabric material and carbonization. More specifically, the textile material may be formed of a carbon support imparted with insulation or conductivity due to carbonization due to heat treatment.

The textile material is a porous structure with pores formed by fibrill strands, and can be selected from animal fibers including vegetable fibers or animal fibers, or artificial fibers including synthetic fibers or regenerated fibers. Specifically, It may include, but is not necessarily limited to, any one or more selected from the group consisting of cotton fibers, silk fibers, cellulose, polyester, nylon, acrylic fibers, and polyacrylonitrile fibers, and may have porosity depending on the fibril structure. As long as it corresponds to a structure, it falls within the scope of the present invention.

Unlike the existing carbonization technology, the carbonization process according to the heat treatment performed in the present invention is carried out at a relatively low temperature in order to have the minimum electrical conductivity possible for electroplating, so that some of the hydrophilic reactors originally contained in the fabric material still remain. exist. Accordingly, the carbon support produced in the present invention is hydrophilic and has a contact angle of 0 to 60°, and preferably, is superhydrophilic and has a contact angle of 0 to 10°.

The contact angle is the angle at which a liquid is thermodynamically balanced on a solid surface and is a measure of the wettability of the solid surface. If the liquid is water, the smaller the contact angle, the higher the wettability and higher surface energy, making it hydrophilic. The higher the contact angle, the lower the wettability and low surface energy, making it hydrophobic. That is, the carbon support has a very low contact angle and high hydrophilicity, so that during electroplating, which will be described later, a catalytic active layer can be evenly formed on the fibril strands inside and the electrolyte can easily penetrate.

In the present invention, the sheet resistance of the carbon support may be 10 ⁰ to 10 ⁴ Ω/sq.

The carbon support may have a minimum sheet resistance that allows electroplating to form a catalytically active layer, which will be described later, and the sheet resistance varies depending on the heat treatment temperature of the fabric material. Therefore, the sheet resistance of the carbon support is preferably 10 ⁰ to 10 ⁴ Ω/sq, and the heat treatment temperature for this is preferably 600 to 1000 ° C. In this range, unlike existing carbonization technology, as the carbonization process progresses at low temperature, the carbon support has hydrophilicity. A conductive carbon support can be formed.

In the present invention, the carbon support may have a surface modified with a thiol group (-SH), a carboxyl group (-COOH), or an amine group (-NH ₂ ).

The fabric-derived conductive carbon support can have its surface modified with various reactors through hydrogen bonding of polymers and single molecules with thiol groups (-SH), carboxyl groups (-COOH), or amine groups (-NH ₂ ). A water decomposition catalyst with excellent stability can be manufactured through chemical bonding with various functional groups of the modified carbon support and the metal catalyst layer.

In the present invention, the catalytically active layer may include a catalyst metal layer and a hydroxide layer or oxyhydroxide layer formed on the catalyst metal layer.

In the present invention, the water decomposition catalyst with a hydroxide layer formed can be used as a cathode for the hydrogen evolution reaction, and the water decomposition catalyst with the oxyhydroxide layer formed as an oxidation electrode for the oxygen evolution reaction.

The catalyst metal layer can be formed by electroplating a catalyst metal on the carbon support, and the catalyst metal is nickel (Ni), cobalt (Co), iron (Fe), molybdenum (Mo), copper (Cu), and vanadium. (V), and tungsten (W).

At this time, when the water decomposition catalyst according to the present invention is used as a reduction electrode for the Hydrogen Evolution Reaction (HER), Ni electroplating is preferable, and the hydrogen generation performance is improved by Ni and Ni(OH) ₂ to be described later. Very excellent. In addition, when the water decomposition catalyst according to the present invention is used as an oxidizing electrode for oxygen evolution reaction (OER), electroplating of Ni, Co, and Fe complex is preferred, and oxides of Ni, Fe, and Co, i.e. NiOOH is formed under the influence of Fe and Co, providing excellent oxygen generation performance.

In the present invention, the hydroxide layer includes Ni(OH) ₂ , and the beta phase of Ni(OH) ₂ may be dominant over the alpha phase. Additionally, the oxyhydroxide layer includes NiOOH. Specifically, the oxyhydroxide layer (Ni(OH) ₂ ) may be formed first, and then the oxyhydroxide layer containing NiOOH may be formed using Ni, Fe, and Co.

In particular, Ni(OH) ₂ is a catalytically active material that plays a role in separating hydrogen from the HO-H bond of water, and affects hydrogen generation and oxygen generation.

Figure 5(A) is a diagram showing the crystal structure of Ni(OH) _2. Ni(OH) ₂ is divided into a) alpha phase and b) beta phase depending on the crystal structure. The hydroxide layer according to the present invention consists of Ni The beta phase of (OH) ₂ appears more dominant than the alpha phase, thereby improving hydrogen generation and oxygen generation performance (Xiaowen Yu et al., ACS Energy Lett., 2018).

The alpha phase of Ni(OH) ₂ is a structure in which H ₂ O is inserted between each Ni(OH) ₂ layer. Due to the bond with H ₂ O inside, H ₂ reacts when water decomposition occurs on the surface. The bonding force with O is weakened, the water decomposition ability is reduced, and the amount of H ₂ O adsorption is small. However, because the beta phase of Ni(OH) ₂ does not have H ₂ O bound inside, it can bond more strongly with H ₂ O reacting on the surface, resulting in excellent water decomposition ability and a small amount of H ₂ O adsorption on the surface. It increases.

The crystal structure of Ni(OH) ₂ depends on the concentration of the nickel salt solution and the current density applied to the cathode. In particular, the alpha phase dominates at relatively low current densities, and the beta phase dominates at high current densities. is formed The electrode produced in the present invention is significant in that it allows electroplating evenly to the inside of the fabric material without over-plating under a sufficiently high current density at which a beta phase is formed.

From another aspect, the present invention relates to a porous water decomposition electrode including the porous water decomposition catalyst.

The water decomposition catalyst according to the present invention can be used as an electrode, and as described above, it can be used as a reduction electrode or an oxidation electrode depending on the catalyst metal to be electroplated.

In another consistent aspect, the present invention includes the steps of (a) carbonizing a fabric material by heat treatment to form a conductive carbon support; and

(b) electroplating the modified carbon support with a catalytic metal to coat a catalytically active layer,

The carbon support formed in step (a) relates to a method for producing a porous water decomposition catalyst having a contact angle of 0 to 60 degrees.

As the water decomposition catalyst according to the present invention has been described above, detailed descriptions of overlapping matters will be omitted or only briefly described.

Specifically, the water decomposition catalyst of the present invention can be manufactured by the same method as the schematic diagram in FIG. 1, and the porous water decomposition catalyst prepared by the above method includes the steps of (c) placing the electrode in an oven and heat treating it at 150°C for 3 hours. ; (d) immersing the electrode in a KOH solution for 1 hour after heat treatment; and (e) washing the water decomposition catalyst on which the catalytic active layer was formed with distilled water and drying it.

In step (a), an insulating fabric material is heat treated and carbonized to form a conductive carbon support. The carbon support formed at this time is hydrophilic and has a contact angle of 0 to 60°, preferably superhydrophilic, and has a contact angle of 0 to 60°. It has a contact angle of between 10 and 10 degrees. In addition, the carbon support is formed as a conductive support having a minimum sheet resistance that allows electroplating to form a catalytically active layer through heat treatment and carbonization, preferably 10 ⁰ to 10 ⁴ Ω/ through heat treatment at 600 to 1000°C. It can have a sheet resistance of sq.

In the present invention, step (a) may further include modifying the surface of the carbon support with a thiol group (-SH), carboxyl group (-COOH), or amine group (-NH ₂ ).

The above step is a step of modifying the surface of the carbon support with a thiol group (-SH), carboxyl group (-COOH), or amine group (-NH ₂ ), and the surface can be modified in various ways through hydrogen bonding between polymers and single molecules having the functional groups. It can be modified with a reactor, and a water decomposition catalyst with excellent stability can be produced through chemical bonding with various functional groups of the surface-modified carbon support and the metal catalyst layer.

In step (b), the catalytic active layer is coated by electroplating a catalytic metal on a carbon support, and the combination of the catalytic metal used and the catalytic metal according to the purpose of the water decomposition catalyst is as described above. In addition, electroplating makes it possible to coat a uniform catalytic active layer on a carbon support, and because it is done in a simple way and within a short time, the time required to manufacture the catalyst can be shortened, manufacturing costs can be lowered, and efficient control is possible. do.

In addition, when the catalyst metal in step (b) is nickel (Ni), a hydrogen generation reaction water decomposition catalyst can be manufactured. Specifically, in step (b), electroplating is performed with nickel (Ni) to produce Ni. A hydroxide layer containing (OH) ₂ can be formed.

When the catalytic metal in step (b) includes two or more selected from the group consisting of nickel (Ni), cobalt (Co), and iron (Fe), an oxygen generation reaction water decomposition catalyst can be manufactured, specifically, In step (b), first electroplating was performed with nickel (Ni) to form a hydroxide layer containing Ni(OH) ₂ , and then a hydroxide layer consisting of nickel (Ni), cobalt (Co), and iron (Fe) was formed. An oxygen-evolving water decomposition catalyst can be manufactured by secondary plating with two or more metals selected from the group to form an oxyhydroxide layer containing NiOOH.

Furthermore, in step (b), a hydroxide layer located on the catalyst metal layer is formed at the same time as the catalytic active layer is coated by electroplating. In this case, the hydroxide layer includes Ni(OH) ₂ and, in particular, beta of Ni(OH) ₂ This phase dominates the alpha phase, improving hydrogen generation and oxygen generation performance. As such, in the present invention, a hydroxide layer in which the beta phase of Ni(OH) ₂ is superior to the alpha phase can be formed without a post-treatment process.

In other words, the present invention uses a porous fabric material to facilitate the inflow of electrolyte and has a large surface area, making it possible to manufacture a water decomposition catalyst with high performance per unit area, and also to enable plating using a low-temperature carbonization process. It secures minimum conductivity and at the same time has hydrophilic properties due to the remaining heteroatoms, enabling even coating of the inside of the fabric material when introducing various metal catalyst layers through water electrolysis-based electroplating. Additionally, the remaining heteroatoms are connected by chemical bonds to polymers and single molecules with various reactive groups (thiol group, carboxyl group, and amine group), making it possible to replace the surface of the carbon support with various reactive groups. The various reactors of the carbon support form chemical bonds with the metal catalyst layer, increasing the bonding force between the electrode support and the catalyst layer, ultimately maximizing the operating stability of the electrode.

In the present invention, when a water splitting electrode was manufactured by plating various metal catalysts on the interface-designed carbon support, high oxygen generation performance and hydrogen generation performance were observed, and it was confirmed that it had excellent driving stability even under high current.

Hereinafter, the present invention will be described in more detail based on preferred embodiments of the present invention. However, the technical idea of the present invention is not limited or limited thereto and may be modified and implemented in various ways by those skilled in the art.

Example 1: Preparation of water decomposition catalyst and electrode containing carbon support derived from textile material

1-1: Preparation of conductive carbon support derived from textile material

In the present invention, in order to manufacture a carbon support derived from textile fibers, silk fabric (Coasilk, Korea), an insulating fabric material, is first washed with deionized water, dried in an oven, and then heated to 950°C at a rate of 3°C/min. It was carbonized by maintaining it in a furnace under a nitrogen gas flow for 3 hours. The carbon support (CST) formed after carbonization was naturally cooled at room temperature. A carbon support was prepared in the same manner as above using cotton fabric as a control.

1-2: Textile-derived material carbon support surface modification

In order to ensure electrode stability through interfacial design, we attempted to modify the surface of the conductive carbon support derived from the fabric material of the present invention with various functional groups.

First, the conductive carbon support derived from the silk material prepared in Example 1-1 was treated with strong acid at 70°C for 2 hours with H ₂ SO ₄ /HNO ₃ to produce a carbon support modified with a carboxyl group (-COOH) (COOH-CST) ) was prepared. The COOH-CST was then washed with deionized water, dried in an oven, and treated with tris(2-aminoethyl)amine (TREN, Mw 146 g/mol, 5 mg/mol dispersed in ethanol). mL) A carbon support (NH ₂ -CST) modified with an amine group (-NH ₂ ) was prepared by immersing it in a solution for 3 hours.

1-3: Hydrogen generation reaction porous water decomposition catalyst and electrode production

A porous water decomposition catalyst for hydrogen generation reaction was prepared by performing Ni electroplating on the fabric-derived carbon support whose surface was modified with amine groups in Example 1-2. Electroplating was performed at a current density of 360 mA/cm ² for 5 minutes in a Watt bath composition of nickel plating solution (240 g/L NiSO ₄ , 45 g/L NiCl ₂ , 30 g H ₃ BO ₃ ), NH ₂ -CST was used as a cathode, and a nickel plate was used as an anode (Ni loading amount: 40.6 mg/cm ² ). At this time, the manufactured electrode formed a hydroxide layer even without post-processing. Next, the electrode on which the hydroxide layer was formed was washed with deionized water and dried at room temperature (EP Ni-CST).

1-4: Production of oxygen generation reaction porous water decomposition catalyst and electrode

Ni, Fe, and Co electroplating was performed on the fabric-derived carbon support whose surface was modified with amine groups in Example 1-2.

Specifically, an aqueous electrolyte bath containing 3mM Ni(NO ₃ ) ₂ ·6H ₂ O, 3mM Fe(NO ₃ ) ₃ ·9H ₂ O, and 3mM Co(NO ₃ ) ₃ ·6H ₂ O. A NiFeCo layer was deposited on the EP Ni-CST of Example 1-3.

The NiFeCo electroplating process was performed at a current density of 30 mA/cm ² for 10 minutes using a power supply, and EP Ni-CST was used as the cathode and a nickel plate as the anode. After electrodeposition, the coated electrode was washed three times with deionized water and dried to prepare an oxygen evolution water splitting catalyst (EP NiFeCo-CST) electroplated with NiFeCo (NiFeCo loading: 2 mg/cm ² ). .

1-5: Comparative example preparation

<Comparative Example 1: Ni electroplated basic carbon fiber fabric>

A water-splitting electrode was manufactured by electroplating Ni on a basic carbon fiber fabric (Carbon cloth HCP331, Wizmac) in the same manner as above.

<Comparative Example 2: Ni water decomposition catalyst (EL Ni-CST) manufactured by electroless plating>

A water-splitting electrode (EL Ni-CST) was manufactured by plating a textile-derived carbon support whose surface was modified with amine groups with Ni using an electroless deposition method.

Electroless plating was performed by depositing nickel on NH ₂ -CST according to a reported method. First, sensitizing solution (0.05M SnCl ₂ ·2H ₂ O and 0.15M HCl) and PdCl ₂ solution (0.6mM PdCl ₂ and 0.03M HCl) were added to NH ₂ -CST and washed three times with deionized water. Then, a solution of 45 g/L NiSO ₄ ·6H ₂ O, 240 g/L NaH ₂ PO ₂ ·H ₂ O, 30 g/L NaC ₆ H ₅ O ₇ ·2H ₂ O and 50 g/L NH ₄ Cl. were mixed together at room temperature and adjusted to pH 9 using NH ₄ OH. After raising the temperature of the solution to 80°C, NH ₂ -CST substrate was immersed in the mixture and stirred for 30 minutes. After reaction, the samples were washed repeatedly with deionized water and dried at room temperature.

<Comparative Example 3: NiFeCo water decomposition catalyst (Hyd NiFeCo-CST) prepared by hydrothermal synthesis>

Hydrothermal synthesis of NiFeCo on EP Ni-CST was performed according to the reported procedure with slight modifications. Specifically, 4 mmol Ni(NO ₃ ) ₂ ·6H ₂ O, 0.45 mmol Fe(NO ₃ ) ₃ ·9H ₂ O, 0.45 mmol Co(NO ₃ ) ₃ ·6H ₂ O, 20 mmol urea and 8 mmol NH ₄ F were added to the magnetic It was dissolved in 80 mL of deionized water with stirring. Then, the solution was transferred to a 100 mL Teflon-lined stainless-steel autoclave, and the washed EP Ni-CST was immersed in the solution. The autoclave was sealed and maintained at 120°C for 3 hours, then the electrode was washed with deionized water and dried at 60°C for 12 hours to prepare a NiFeCo water decomposition catalyst (Hyd NiFeCo-CST) by hydrothermal synthesis.

<Comparative Example 4: NiFe water decomposition catalyst electroplated with Ni and Fe (EP NiFe-CST)>

Specifically, the EP Ni- of Example 1-3 was prepared using an aqueous electrolyte bath containing 3mM Ni(NO ₃ ) ₂ ·6H ₂ O and 3mM Fe(NO ₃ ) ₃ ·9H ₂ O. A NiFe layer was deposited on the CST.

The NiFe electroplating process was performed at a current density of 30 mA/cm ² for 10 minutes using a power supply, and EP Ni-CST was used as the cathode and a nickel plate as the anode. After electrodeposition, the coated electrode was washed three times with deionized water and dried to prepare an oxygen evolution reaction water splitting catalyst (EP NiFe-CST) electroplated with NiFe (NiFe loading amount: 2 mg/cm ² ). .

<Comparative Example 5: Pt/C electrode>

Specifically, the Pt/C electrode was prepared by dispersing 1 mg of Pt/C (20 wt% Pt in Vulcan XC-72) in 300 μL of an EtOH solution containing 10.5 μL of 5 wt% Nafion. The resulting catalyst ink solution was coated with CST or commercial Ni foam (0.5 × 0.5 cm ² , Goodfellow Cambridge Ltd, UK) and then dried at room temperature.

<Comparative Example 6: IrO ₂ electrode>

Specifically, the IrO ₂ electrode was prepared by dispersing 1 mg of IrO ₂ in 300 μL of an EtOH solution containing 10.5 μL of 5% by weight Nafion. The IrO ₂ catalyst ink solution was deposited on CST or commercial Ni foam (0.5 × 0.5 cm ² ) in the same manner as the Pt/C electrode and then dried at room temperature.

Example 2: Preparation and characterization of carbon support derived from textile material

To analyze the properties of the carbon support prepared in Example 1-1, the contact angle was measured using a Phoenix 300 instrument (S.E.O. Co., Ltd.).

As a result, as shown in Figure 2, the existing carbon fabric cloth had a very large contact angle of 117°, whereas the carbon support derived from the fabric material of the present invention had a very small contact angle of 0°, showing that it had hydrophilic properties. confirmed.

This is because the fabric-derived carbon support of the present invention is heat-treated at a relatively lower temperature than the existing carbonization process, and heteroatoms (nitrogen and oxygen) are present, resulting in hydrophilic properties.

In addition, the degree of conductivity and sheet resistance according to the type of fabric and carbonization temperature was confirmed.

As a result, as shown in Figure 3, it was possible to manufacture a carbon support with conductivity capable of electroplating through carbonization through heat treatment for both silk and cotton materials. In particular, as the heat treatment temperature increased, sheet resistance decreased and conductivity increased. In the case of silk material, it was possible to form a carbon support with high electrical conductivity of 4.3 S/cm due to a low sheet resistance of 6.6 Ω/sq at 950℃, and in the case of cotton material, it was possible to form a carbon support of 1.1×10 ² Ω/sq at 950℃. It was possible to form a carbon support with high electrical conductivity of 0.23 S/cm due to low sheet resistance.

Example 3: Characterization of surface-modified carbon support

The surface of the carbon support derived from the surface-modified textile material of Example 1-2 was analyzed using Fourier transform infrared spectroscopy (FT-IR). Fourier transform infrared (FTIR) spectroscopy results were obtained with a Cary 600 spectrometer (Agilent Technology) operated at 4/cm resolution in attenuated total reflection (ATR) mode, and the obtained data were plotted using spectral analysis software (OMNIC, Nicolet). .

As shown in Figure 4, when the surface of the carbon support is modified with a carboxyl group, a C=O peak can be confirmed in the FT-IR graph, and when combined with a polymer or single molecule having an amine group, an N-H peak appears. did.

Example 4: Analysis of the structure of the catalyst metal layer formed by electroplating

In the present invention, the hydroxide layer structure of the hydrogen generation reaction porous water decomposition catalyst prepared in Examples 1-3 was analyzed using X-ray diffraction (XRD). X-ray diffraction (XRD) analysis was performed on a SmartLab instrument (Rigaku) with a Cu Kα radiation source.

As a result _of performing an It was confirmed that Ni(OH) ₂ was formed.

Example 5: Evaluation of conductivity and sheet resistance according to electroplating

In the present invention, the conductivity and sheet resistance of the water decomposition catalyst prepared in Examples 1-3 were measured according to the electroplating time.

As a result of electroplating a conductive hydrophilic carbon support with a nickel plating solution of a Watt bath composition, it was possible to manufacture a hydrogen generating electrode with electrical conductivity similar to that of metal. Electroplating was performed for a short period of 5 minutes to produce a 0.05 Ω Due to the low sheet resistance of /sq, high electrical conductivity of 476.2 S/cm could be provided.

Example 6: Evaluation of the microstructure of the carbon support and the coating of the catalyst metal layer

To evaluate the microstructure of the carbon support and the coating of the catalyst metal layer of the porous water decomposition catalyst prepared in the present invention, SEM (Scanning Electron Microscopy) and EDX (Energy Dispersive X-Ray Analysis) were used. ) analysis was performed. SEM and EDX images were obtained via field emission SEM (FE-SEM) (Quanta 250 FEG, FEI).

Figure 7 is an image of the surface of the carbon support measured by SEM at each stage of manufacturing the porous water decomposition catalyst, and Figure 8 shows the surface of the carbon support of the Ni electroplated porous water decomposition catalyst, NiFeCo electroplated porous water decomposition catalyst, and commercial Ni foam. This is an image measured with SEM.

As shown in Figures 7 and 8, it was confirmed that the pore structure of the fabric material was maintained even after electroplating, facilitating electrolyte inflow, and that the metal was adsorbed very uniformly.

In addition, it was confirmed through SEM high-magnification images that a protruding structure and a nano sheet array were formed, and the high surface area resulting from this structure is expected to maximize performance per unit area (cm ² ).

Example 7: Comparison of properties of the porous water decomposition catalyst of the present invention and a catalyst manufactured by existing technology

7-1: Analysis of water decomposition catalyst characteristics according to type of carbon support

The Ni electroplated porous water splitting catalyst (EP Ni-CST) prepared in Examples 1-3 of the present invention and the Ni electroplated basic carbon fiber fabric of Comparative Example 1 were analyzed by EDX.

As shown in Figure 9, it was confirmed that the catalyst metal layer was uniformly coated even on the fibril strands inside the hydrophilic carbon support derived from the textile material produced in the present invention. This leads to maximization of the amount of catalyst per unit area and can improve the electrical conductivity and water decomposition ability of the electrode.

7-2: Electroless plating method and analysis of water decomposition catalyst characteristics according to the present invention

The Ni electroplated porous water decomposition catalyst (EP Ni-CST) prepared in Examples 1-3 of the present invention and the Ni electroless-plated water decomposition catalyst (EL Ni-CST) of Comparative Example 2 were examined by SEM and EDX. analyzed.

As shown in Figure 10, unlike the catalyst electrode manufactured through the existing electroless plating method, the porous water decomposition catalyst according to the present invention uses a hydrophilic carbon support, so when performing water electrolysis-based electroplating, the metal catalyst layer becomes a fabric. It was confirmed that plating progressed evenly to the inside while maintaining the porosity. In addition, it was confirmed that a plating layer was formed in the form of protrusions on the surface of the electrode fibrils, increasing the overall surface area of the electrode.

7-3: Hydrothermal synthesis method and analysis of water decomposition catalyst characteristics according to the present invention

The NiFeCo electroplated porous water decomposition catalyst (Electroplated NiFeCo. oxygen evolution reaction) prepared in Examples 1-4 of the present invention and the NiFeCo water decomposition catalyst (Hyd NiFeCo-CST) prepared by the hydrothermal synthesis method of Comparative Example 3 were examined by SEM and Analyzed by EDX.

As shown in Figure 11, unlike the catalyst electrode manufactured by hydrothermal synthesis, the porous water decomposition catalyst according to the present invention was confirmed to be evenly plated to the inside of Ni, Fe, and Co while maintaining the porosity of the fabric, and the electrode fibril It was confirmed that a plating layer was formed on the surface in the form of a nano array, increasing the surface area of the electrode.

The porosity of such fabric materials facilitates electrolyte inflow, and the increase in the surface area of the electrode due to additional plating has the advantage of maximizing performance per unit area (cm ² ).

In addition, as shown in Figure 12, the NiFeCo electroplated porous water decomposition catalyst (EP NiFeCo-CST) and the NiFeCo porous water decomposition catalyst (Hyd NiFeCo-CST) prepared by hydrothermal synthesis were analyzed through As a result of checking the crystal structure, it was confirmed that EP NiFeCo-CST had an amorphous structure and Hyd NiFeCo-CST had a crystalline structure.

Example 8: Bending test analysis of the porous water splitting catalyst of the present invention

In the present invention, a bending test of the Ni electroplated porous water decomposition catalyst (EP Ni-CST) and NiFeCo electroplated porous water decomposition catalyst (EP NiFeCo-CST) prepared in Examples 1-3 and 1-4 (bending test) was performed.

As a result, as shown in Figure 13, unlike existing carbon and metal electrodes, the water-splitting electrode manufactured in the present invention retains the flexibility of the fabric material even after metal electroplating, and can be tested in a bending test of about 5,000 sides. It was confirmed that high electrical conductivity was maintained even after this and that stability was excellent.

Example 9: Confirmation of water decomposition ability of the porous water decomposition catalyst of the present invention

9-1: Checking hydrogen generation reaction performance

To confirm the hydrogen generation performance and overpotential degree of the hydrogen generation reaction porous water splitting catalyst (EP Ni-CST) prepared in Examples 1-3 of the present invention, linear sweep voltammetry was performed in 1M KOH electrolyte. , LSV) was used to analyze it. All reported current densities are based on the geometric surface area of the electrode.

Inductively coupled plasma mass spectrometry (ICP-MS, Agilent Technologies 7700) was performed to measure the amount of Ni ions dissolved in the electrolyte after the hydrogen evolution reaction (HER).

As a control, the carbon support (CST) derived from a textile material prepared in Example 1-1 was used, and Comparative Example 2 (EL Ni-CST) and Comparative Example 5 (Pt/C/Ni foam) of Example 1-5 were used. The hydrogen generation performance and overvoltage level of the water decomposition catalyst were analyzed in the same manner as above.

As a result, as shown in Figure 14, the EP Ni-CST of the present invention was confirmed to have significantly better hydrogen generation performance compared to commercially sold Pt/C/Ni foam, and the EL Ni-CST manufactured by the existing method It was confirmed to have a much lower overvoltage compared to .

9-2: Checking oxygen generation reaction performance

To confirm the oxygen generation performance and overpotential degree of the oxygen generation reaction porous water splitting catalyst (EP NiFeCo-CST) prepared in Examples 1-4 of the present invention, linear sweep voltammetry was performed in 1M KOH electrolyte. , LSV) was used to analyze it.

Inductively coupled plasma mass spectrometry (ICP-MS, Agilent Technologies 7700) was performed to measure the amounts of Ni, Fe, and Co ions dissolved in the electrolyte after the oxygen evolution reaction (OER).

EP Ni-CST, a porous water splitting catalyst for hydrogen generation reaction of the present invention, was used as a control, and Comparative Example 3 (Hyd NiFeCo-CST), Comparative Example 4 (EP NiFe-CST) and Comparative Examples of Examples 1-5 were used as a control group. The water decomposition catalyst of 6 (IrO ₂ /Ni foam) was also analyzed for oxygen generation performance and overvoltage level in the same manner as above.

As shown in Figure 15, it was confirmed that the EP NiFeCo-CST of the present invention has superior oxygen generation performance than commercially sold IrO ₂ /Ni foam. In addition, it was confirmed that the EP NiFeCo-CST of the present invention has much higher oxygen generation performance than Hyd NiFeCo-CST (Comparative Example 3) and the NiFe water decomposition catalyst known to have high oxygen generation performance (Comparative Example 4).

Example 10: Evaluation of properties of water decomposition electrode manufactured with the porous water decomposition catalyst of the present invention

In the present invention, the Ni electroplated porous water decomposition catalyst of Example 1-3 is connected as a cathode, and the NiFeCo electroplated porous water decomposition catalyst of Example 1-4 is connected as an anode. [EP Ni(-)∥EP NiFeCo/Ni(+)] was prepared (FIG. 16(A)), and the current density and electrode efficiency of the two-electrode system were analyzed.

As a control, a water decomposition electrode was connected with Pt/C/Ni foam as the cathode and IrO ₂ /Ni foam as the anode [Pt/C(-)∥ ₂ (+)], and a porous water decomposition catalyst electroless plated with Ni as the cathode. As a result, a water decomposition electrode [EL Ni(-)∥Hyd NiFeCo/Ni(+)] was used, in which a NiFeCo porous water decomposition catalyst prepared by hydrothermal synthesis was connected to the anode.

As shown in Figure 16(B), when the current density performance was measured by configuring a two-electrode system, the water-splitting electrode of the present invention had very excellent performance compared to existing commercialized electrodes, and had a low voltage under high current. It was confirmed that the voltage value was indicated. In addition, as shown in Figure 16 (C), as a result of conducting an electrode efficiency test, it was confirmed that the amount of oxygen and hydrogen generated from each electrode was 99.8% consistent with the theoretical amount, which is consistent with the water decomposition of the present invention. This means that the electrode is a very efficient water splitting electrode in which no other side reactions occur.

Figure 17 compares the performance of the previously disclosed water-splitting electrode and the water-splitting electrode of the present invention. It was confirmed that the water-splitting electrode of the present invention exhibits a lower overvoltage compared to other water-splitting electrodes and has excellent water-splitting performance. .

Furthermore, in order to confirm the driving stability of the water-splitting electrode of the present invention, the water-splitting electrode of the present invention was driven for a long time at various current densities, and as shown in Figures 18 and 19, unlike the control group, the water-splitting electrode of the present invention had a voltage value of It was confirmed that it remained constant. In particular, as a result of observing with SEM while maintaining a constant voltage value for more than 1,640 hours at a current density of 2,000 mA/cm ² , it was confirmed that the surface protrusion structure and nano array structure did not change and desorption and peeling did not occur even after long-term operation. did.

In the present invention, the porous water decomposition catalyst manufactured using a highly hydrophilic carbon support with minimum electrical conductivity capable of electroplating has excellent charge transport ability, facilitates electrolyte penetration, and has high water decomposition performance. There is. In addition, the water decomposition catalyst produced in the present invention has high driving stability, capable of maintaining a low voltage for a long time even at high currents, and can be used to manufacture water decomposition electrodes without size or shape restrictions, so it can be usefully used in the manufacture of water decomposition electrodes. You can.

Claims (19)

1. Conductive carbon support derived from textile material;

   It includes a catalytically active layer formed on the conductive carbon support,

   The conductive carbon support is hydrophilic, a porous water decomposition catalyst.
2. According to paragraph 1,

   The conductive carbon support derived from the fabric material is a porous water decomposition catalyst, characterized in that it is a conductive carbon support formed by carbonization by heat treatment of the fabric material.
3. According to paragraph 1,

   A porous water decomposition catalyst, wherein the fabric material includes at least one selected from the group consisting of cotton fibers, silk fibers, cellulose, polyester, nylon, acrylic fibers, and polyacrylonitrile fibers.
4. According to paragraph 1,

   A porous water decomposition catalyst, characterized in that the sheet resistance of the conductive carbon support derived from the textile material is 10 ⁰ to 10 ⁴ Ω/sq.
5. According to paragraph 1,

   The conductive carbon support derived from the textile material is a porous water decomposition catalyst, characterized in that the surface is modified with a thiol group (-SH), a carboxyl group (-COOH), or an amine group (-NH ₂ ).
6. According to paragraph 1,

   A porous water decomposition catalyst, wherein the catalytically active layer includes a catalyst metal layer and a hydroxide layer or oxyhydroxide layer formed on the catalyst metal layer.
7. According to clause 6,

   The catalyst metal layer contains at least one selected from the group consisting of nickel (Ni), cobalt (Co), iron (Fe), molybdenum (Mo), copper (Cu), vanadium (V), and tungsten (W). A porous water decomposition catalyst comprising:
8. According to clause 6,

   The hydroxide layer includes Ni(OH) ₂ ,

   A porous water decomposition catalyst, characterized in that the beta phase of Ni(OH) ₂ is dominant over the alpha phase.
9. According to clause 6,

   A porous water decomposition catalyst, characterized in that the oxyhydroxide includes NiOOH.
10. According to paragraph 1,

    The porous water decomposition catalyst is a hydrogen generation reaction water decomposition catalyst when the catalytically active layer includes a hydroxide layer,

    A porous water decomposition catalyst, characterized in that it is an oxygen evolution reaction water decomposition catalyst when the catalytically active layer includes an oxyhydroxide layer.
11. A porous water decomposition electrode comprising the porous water decomposition catalyst of any one of claims 1 to 10.
12. (a) carbonizing the fabric material through heat treatment to form a conductive carbon support; and

    (b) electroplating the carbon support with a catalytic metal to coat a catalytically active layer,

    A method for producing a porous water decomposition catalyst, wherein the carbon support formed in step (a) is hydrophilic.
13. According to clause 12,

    A method for producing a porous water decomposition catalyst, wherein the fabric material includes at least one selected from the group consisting of cotton fibers, silk fibers, cellulose, polyester, nylon, acrylic fibers, and polyacrylonitrile fibers. .
14. According to clause 12,

    A method for producing a porous water decomposition catalyst, characterized in that the heat treatment in step (a) is performed at 600 to 1000°C.
15. According to clause 12,

    The step (a) further includes the step of modifying the surface of the carbon support with a thiol group (-SH), carboxyl group (-COOH), or amine group (-NH ₂ ) of the porous water decomposition catalyst. Manufacturing method.
16. According to clause 12,

    In step (b), the catalyst metal is selected from the group consisting of nickel (Ni), cobalt (Co), iron (Fe), molybdenum (Mo), copper (Cu), vanadium (V), and tungsten (W). A method for producing a porous water decomposition catalyst, characterized in that it includes one or more of the following.
17. According to clause 12,

    When the catalyst metal in step (b) is nickel (Ni), a porous water decomposition catalyst for hydrogen generation reaction in which a hydroxide layer containing Ni(OH) ₂ is formed is manufactured,

    A method for producing a porous water decomposition catalyst, characterized in that the beta phase of Ni(OH) ₂ is superior to the alpha phase.
18. According to clause 12,

    When the catalyst metal in step (b) contains two or more selected from the group consisting of nickel (Ni), cobalt (Co), and iron (Fe), oxygen generation reaction in which an oxyhydroxide layer containing NiOOH is formed porous water decomposition A method for producing a porous water decomposition catalyst, characterized in that the catalyst is produced.
19. According to clause 18,

    The oxyhydroxide layer containing NiOOH is first electroplated with nickel (Ni) to form a hydroxide layer containing Ni(OH) ₂ , and then nickel (Ni), cobalt (Co), and iron (Fe). ) A method for producing a porous water decomposition catalyst, characterized in that it is formed by secondary plating with two or more metals selected from the group consisting of.

Images