KR102144722B1 - Catalyst complex for hydrogen production using 3-dimensional polymer and method for producing the same - Google Patents

Abstract

[일반식 (3)]

상기 일반식 (1) 및 (3)에서, Ra₁ 내지 Ra₆과 Rb₁ 내지 Rb₆은 각각 탄소(C)이고,
상기 일반식 (1)에서, X₁ 내지 X₆은 각각 독립적으로 산소 또는 아민기로 선택되고,
상기 일반식 (3)에서, Y₁ 내지 Y₆은 X₁ 내지 X₆와 이민결합을 형성하는 것을 전제로 각각 종속적으로 산소 또는 아민기로 선택된다(X_A, Y_A가 산소일 때, R_aA-X_A, R_bA-Y_A는 카르보닐기이고, A는 1 내지 6 이하의 자연수).The present specification provides a carrier comprising 1 to 99 mol% of monomer a represented by the following general formula (1) and 1 to 99 mol% of monomer b represented by the following general formula (3); And a catalyst complex for generating hydrogen containing a metal atom.
[General Formula (1)]

[General Formula (3)]

In the general formulas (1) and (3), Ra ₁ to Ra ₆ and Rb ₁ to Rb ₆ are each carbon (C),
In the general formula (1), X ₁ to X ₆ are each independently selected from an oxygen or amine group,
In the general formula (3), Y ₁ to Y ₆ are each independently selected as an oxygen or amine group on the premise of forming an imine bond with X ₁ to X ₆ (when X _{A and} Y _A are oxygen, R _aA -X _A , R _bA -Y _A is a carbonyl group, and A is a natural number of 1 to 6 or less).

Description

Catalyst complex for hydrogen production using 3-dimensional polymer and method for producing the same}

The present invention relates to the production of a catalyst using a three-dimensional polymer structure containing nitrogen and a metal, and a hydrogen generation method using the same.

Hydrogen is evaluated as a clean energy resource, and as an alternative energy, it is a gas required in many energy conversion and storage fields such as hydrogen fuel cell vehicles and fuel cells. Hydrogen evolution reaction (HER) using water electrolysis is a method to obtain hydrogen gas cleanly, but it is difficult to commercialize it because it is more expensive than that obtained through fossil fuel reforming in terms of manufacturing cost. In order to be applied to the actual industrial field, excellent durability, high efficiency, and price competitiveness are required, and it is essential that the catalyst proceeds with minimum overvoltage and rapid reaction. However, the catalyst used in the present hydrogen generation reaction has a low stability and thus has limitations in that the catalyst is lost and the electrode must be frequently replaced after the reaction.

Platinum-based catalysts are known as the most efficient catalysts in an acidic environment, and they show fast reaction rates due to strong binding with protons. However, precious metals such as platinum have low stability in a fugitive environment, which inevitably increases the burden in industries with high demand for platinum. Recently, a nonmetal-based catalyst has been studied to solve this problem, but it has a problem of corrosion in an acidic environment, and has a problem in terms of low performance, cost and productivity due to high overvoltage compared to platinum (Nat. Commun., 2014) , 5, 3783, Nat. Mater., 2012, 11, 802-807). Among the noble metal-based catalysts, ruthenium and iridium-based catalysts show comparable performance to platinum, but the stability problem has not been solved.

In order to improve the stability, studies of loading nano-sized metal particles on a two-dimensional polymer structure are actively taking place (Nat. Nanotech., 2017, 12, 441-447, J. Am. Chem. Soc., 2018, 140 , 1737-1742). However, the two-dimensional structure provides stability, but at the same time has the disadvantage of offsetting part of the catalytic active space. If the stability is improved and the catalytic active space is maintained at the same time, since it has the advantage that it can be used for a long time even in a small amount, it is time to solve this technology.

Accordingly, there is a need for development of a hydrogen production catalyst having excellent catalytic activity stability while securing a catalytic activity space.

In addition, for practical application in industrial fields, development of a hydrogen production catalyst having excellent catalytic activity and stability in a wide range of pH is required.

Korean Patent Registration No. 10-1803738

An object of the present invention is to provide a hydrogen production catalyst having excellent catalytic activity stability while securing a catalytic activity space.

An object of the present invention is to provide a hydrogen production catalyst having excellent catalytic activity and stability in a wide range of pH ranges for practical application in industrial fields.

As a means for achieving the above object, the present specification includes 1 to 99 mol% of monomer a represented by one of the following general formulas (1) to (2) and 1 represented by one of the following general formulas (3) to (5) A carrier comprising to 99 mol% of monomer b; And a catalyst composite comprising a metal atom.

[General Formula (1)]

[General Formula (2)]

[General Formula (3)]

[General Formula (4)]

[General formula (5)]

In the general formulas (1) to (2), X ₁ to X ₆ are each independently selected as an oxygen or amine group,

In the general formulas (3) to (5), Y ₁ to Y ₆ are each independently selected as an oxygen or amine group on the premise of forming an imine bond with X ₁ to X ₆ (X _{A ,} Y _A is oxygen. _Wherein R _aA -X _A , R _bA -Y _A is a carbonyl group, and A is a natural number of 1 to 6 or less).

In each catalyst composite of the present invention, in general formulas (1) to (2), X ₁ to X ₆ are all selected from oxygen or amine groups, and in general formulas (3) to (5), Y ₁ to Y ₆ It is preferable that X ₁ to X ₆ are all independently selected as an oxygen or amine group on the premise of forming an imine bond.

In each of the catalyst composites of the present invention, it is preferable that the support includes cage-like voids formed by repeatedly reacting monomers a and b.

In each catalyst composite of the present invention, the metal atoms are iridium (Ir), cerium (Ce), iron (Fe), rhodium (Rh), palladium (Pd), comalt (Co), nickel (Ni), gold ( Au), silver (Ag), manganese (Mn), zinc (Zn), copper (Cu) and molybdenum (Mo) is preferably at least one selected from the group consisting of.

In each of the catalyst composites of the present invention, it is preferable that the catalytic activity is maintained at a pH concentration of 0 or more and 14 or less.

In addition, as a means for achieving the above-described object, the present specification includes a) a metal precursor, 1 to 99 mol% of monomer a represented by one of the following general formulas (1) to (2), and the following general formulas (3) to ( 5) dissolving 1 to 99 mol% of monomer b represented by one of them in an organic solvent; b) adding a reducing agent to the solution in step a) to obtain a precipitate; and a method for producing a catalyst composite comprising:

[General Formula (1)]

[General Formula (2)]

[General Formula (3)]

[General Formula (4)]

[General formula (5)]

In the general formulas (1) to (2), X ₁ to X ₆ are each independently selected as an oxygen or amine group,

In the general formulas (3) to (5), Y ₁ to Y ₆ are each independently selected as an oxygen or amine group on the premise of forming an imine bond with X ₁ to X ₆ (X _{A ,} Y _A is oxygen. _Wherein R _aA -X _A , R _bA -Y _A is a carbonyl group, and A is a natural number of 1 to 6 or less).

In the method for preparing each catalyst composite of the present invention, the metal precursors in step a) are iridium (Ir), cerium (Ce), iron (Fe), rhodium (Rh), palladium (Pd), comalt (Co), It is preferable to include at least one metal selected from the group consisting of nickel (Ni), gold (Au), silver (Ag), manganese (Mn), zinc (Zn), copper (Cu), and molybdenum (Mo).

In the method for preparing each catalyst composite of the present invention, the monomer a and the monomer b in step a) are preferably dissolved in a molar ratio of 1:2 to 2:1.

In the method for preparing each catalyst complex of the present invention, the organic solvent in step a) is N,N-dimethylforamide (DEF), N,N-dimethylacetamide (N,N- It is preferable to include at least one from the group consisting of dimethylacetamide, DMAC), dimethylsulfoxide (DMSO), hexamethylphosphoramide (HMPA), and N-methylpyrrolidone (NMP). .

In the method for preparing each catalyst composite of the present invention, the reducing agent in step b) is from the group consisting of lithium borohydride (LiBH ₄ ), lithium aluminum hydride (LiAlH ₄ ), sodium borohydride (NaBH ₄ ), or hydrazine. It is preferable to include one or more.

In the method for preparing each catalyst composite of the present invention, the precipitate in step b) is preferably obtained by filtering using a polytetrafluoroethylene (PTFE) membrane.

In the method for preparing each catalyst composite of the present invention, it is preferable that reflux is performed in step b).

In the method for preparing each catalyst composite of the present invention, it is preferable to further include a step in which reflux is performed at 150 to 200°C between steps a) and b).

In the method for preparing each catalyst composite of the present invention, after step b), heat treatment at 700 to 900° C. for 1 to 3 hours in an inert gas atmosphere; it is preferable to further include.

The present invention provides a catalyst composite having excellent catalytic activity and stability by allowing the cage-like voids of the three-dimensional polymer carrier to be supported on the carrier in a uniform distribution of metal atoms.

In addition, the present invention provides a catalyst composite having excellent catalytic activity and stability in a wide range of pH.

1 is a simplified diagram of the manufacturing process of the catalyst composite of the present invention.
2A is a plan view as viewed from the x, y, and z axes of the present invention carrier.
2B is an xy plan view of the carrier of the present invention.
2C is a yz plan view of the carrier of the present invention.
3A is a plan view as viewed from the x, y, and z axes of the amount of the catalyst composite of the present invention.
3B is an xy plan view of the catalyst composite of the present invention.
3C is a plan view yz of the catalyst composite of the present invention.
4A is an SEM image of Example 1. (Scale bar: 2㎛)
4B is an SEM image of Example 1. (Scale bar: 0.5㎛)
5 is an X-ray diffraction pattern of Example 1. FIG.
6 is a nitrogen-adsorption-desorption isotherm of Example 1.
7 is a graph of pore size distribution in Example 1.
8 is an AR-TEM image of Example 1. (Scale bar: 4nm)
9 is a HAADF image and an EDX image (C, Ir, N) of Example 1 in turn from the left.
10A is a graph of polarization curves for hydrogen reduction reactions of Example 1 and Comparative Examples in an acidic environment (pH 0 to 0.3).
10B is an enlarged graph of FIG. 10A.
FIG. 10C shows a Tafel slope graph of Example 1 and each of the comparative examples from the results of FIG. 10A.
10D is a graph comparing overvoltage and exchange current density in Example 1 and each of the comparative examples from the results of FIG. 10A.
10E is a polarization curve graph for the hydrogen reduction reaction of Example 1 and Comparative Examples after 10,000 hydrogen generation tests in an acidic environment (pH 0 to 0.3).
10F is an image for confirming that the structure of Example 1 is stably maintained after the hydrogen generation test of FIG. 10E. It is the HAADF image and the EDX image (C,Ir,N) of Example 1, each of which was tested 10,000 times in order from the left.
10g is a table for comparing overvoltages of Example 1 and Comparative Examples 1 and 2, and known catalysts in an acidic environment (pH 0 to 0.3) (aqueous sulfuric acid solution of 0.5M).
10H is a table for comparing the overvoltage and TOF of Example 1 and Comparative Examples 1 and 2, and known hydrogen generation reaction catalysts in an acidic environment (pH 0 to 0.3) (sulfuric acid aqueous solution 0.5M).
11A is a graph of polarization curves for hydrogen reduction reactions of Example 1 and Comparative Examples in a basic environment (pH 14).
11B is an enlarged graph of FIG. 11A.
FIG. 11C shows a Tafel slope graph of Example 1 and each of the comparative examples from the results of FIG. 11A.
11D is a graph comparing overvoltage and exchange current density in Example 1 and each of the comparative examples from the results of FIG. 11A.
11E is a polarization curve graph for the hydrogen reduction reaction of Example 1 and Comparative Examples after 10,000 hydrogen generation tests in a basic environment (pH 14).
11F is an image for confirming that the structure of Example 1 is stably maintained after the hydrogen generation test of FIG. 11E. It is the HAADF image and the EDX image (C,Ir,N) of Example 1, each of which was tested 10,000 times in order from the left.
11G is a table for comparing overvoltages of Example 1 and Comparative Examples 1 and 2 and known catalysts in a basic environment (pH 14) (aqueous potassium hydroxide solution of 1.0M).
11H is a table for comparing the overvoltage and TOF of Example 1 and Comparative Examples 1 and 2 and known hydrogen generation reaction catalysts in a basic environment (pH 14) (aqueous potassium hydroxide solution of 1.0M).

The terms used in this application are only used to describe specific examples. So, for example, a singular expression includes a plural expression unless the context clearly has to be singular. In addition, terms such as "include" or "include" used in the present application are used to clearly refer to the existence of features, steps, functions, components, or combinations thereof described in the specification, but other features It should be noted that it is not used to preliminarily exclude the presence of elements, steps, functions, components, or combinations thereof.

Meanwhile, unless otherwise defined, all terms used in this specification should be viewed as having the same meaning as commonly understood by a person of ordinary skill in the art to which the present invention belongs. Therefore, unless clearly defined in the specification, specific terms should not be interpreted in an excessively ideal or formal meaning.

In addition, "about", "substantially" and the like in the present specification are used at or close to the numerical value when manufacturing and material tolerances specific to the stated meaning are presented, and are accurate to aid understanding of the present invention. Or absolute figures are used to prevent unfair use of the stated disclosure by unconscionable infringers.

In addition, "CON" in the present specification is a three-dimensional polymer carrier manufactured according to the manufacturing method of the present invention, including the polymer carrier manufactured according to the manufacturing method described in Examples, It may be interpreted as a three-dimensional polymer carrier capable of carrying metal atoms within an understandable range.

In addition, in the present specification, "monomer a" is a monomer of a carrier (CON) and may be represented by one of the following general formulas (1) to (2).

[General Formula (1)]

[General Formula (2)]

In the general formulas (1) to (2), X ₁ to X ₆ are each independently selected from oxygen or an amine group (when X _A is oxygen, R _aA -X _A is a carbonyl group, and A is 1 to 6 or less Natural number).

In addition, in the present specification, "monomer b" is a monomer of a carrier (CON), and may be represented by one of the following general formulas (3) to (5).

[General Formula (3)]

[General Formula (4)]

[General formula (5)]

In the general formulas (3) to (5), Y ₁ to Y ₆ are each independently selected as an oxygen or amine group on the premise of forming an imine bond with X ₁ to X ₆ (when Y _A is oxygen, R _bA -Y _A is a carbonyl group, A is a natural number of 1 to 6 or less).

In addition, in the present specification, "cage-type voids" are voids formed in the carrier (CON) formed as a result of growth with symmetry in three directions as the monomer b adheres to the edge of the monomer a, surrounding metal atoms in all directions. It is a void that can be tightly fixed by being wrapped.

Hereinafter, the problem solving means of the present invention will be described in detail.

<Catalyst composite of the present invention>

The catalyst composite of the present invention may include a support including 1 to 99 mol% of monomer a and 1 to 99 mol% of monomer b and a metal atom. Hereinafter, each configuration of the catalyst composite of the present invention will be described in detail.

Carrier (CON)

In the present invention, the carrier (CON) may be a reactant of a monomer a represented by one of formulas (1) to (2) and a monomer b represented by one of formulas (3) to (5).

In the present invention, the monomer a represented by one of the following general formulas (1) to (2) may contain a bicyclo unit. X ₁ to X ₆ of the monomer a may each independently be selected with an oxygen or amine group, but preferably all of X ₁ to X ₆ of the monomer a may be selected with an oxygen or amine group so that the monomer a may have a C _3v symmetry. _Yes (when X _A is oxygen, R _aA -X _A is a carbonyl group, and A is a natural number of 1 to 6 or less).

[General Formula (1)]

[General Formula (2)]

However, monomer a is not interpreted as being limited to the compound represented by one of the general formulas (1) to (2) of monomer a as described above, and monomer a is imine through a Schiff base reaction with the functional group of monomer b. Assuming that it is cyclized by a bond, it can be expressed as a compound of various cyclic structures having symmetry while including a bicyclo unit.

As an example of the present invention monomer a, the monomer a may be represented by the following formula (1) (triptycene hexamine (THA), molecular weight 344.42 g/mole).

[Formula (1)]

In the present invention, the monomer b may be represented by one of the following general formulas (3) to (5). Y ₁ to Y ₆ of the monomer b may be independently selected as an oxygen or amine group on the premise that X ₁ to X ₆ and an imine bond are formed. Monomer b is preferably, when all of X ₁ to X ₆ of the monomer a are selected as oxygen or amine groups, on the premise that Y ₁ to Y ₆ of the monomer b forms an imine bond with X ₁ to X ₆ All may be selected from oxygen or amine groups (when Y _A is oxygen, R _bA -Y _A is a carbonyl group, and A is a natural number of 1 to 6 or less).

[General Formula (3)]

[General Formula (4)]

[General formula (5)]

However, the monomer b is not limited to the compound represented by one of the general formulas (3) to (5) of the monomer b as described above and is not interpreted, and is a ring as an imine bond through the functional group of the monomer a and Schiff base reaction. It may be expressed as a cyclic compound of C ₆ , C ₉ , C ₁₂ or a compound of various cyclic structures having symmetry while including a hexane unit.

As an example of the present invention monomer b, the monomer b may be represented by the following formula (2) (hexaketocyclohexane (HKH), molecular weight 168.06 g/mole).

[Formula (2)]

The carrier (CON) of the present invention may be an organic structure obtained by repeatedly reacting monomer a and monomer b. The monomer a and the monomer b may form a carrier (CON) through an irreversible reaction, and when the two molecules start the reaction, the monomer b adheres to the edge of the monomer a and grows with symmetry in three directions. The carbonyl group and the amine group of the monomers a and b in which the reaction is performed may be cyclized by an imine bond through a Schiff base reaction.

2A to 2C of the present specification are a plan view, an x-y plan, and a y-z plan view as viewed from the positive x, y, and z axes of the present invention carrier CON. 2A to 2C, the carrier (CON) of the present invention is structurally stable because all bonds are formed in a hexagonal ring shape. Further, the carrier (CON) of the present invention is an organic structure and may be superior to other known carriers in terms of stability. The carrier (CON) of the present invention does not react with water and has high heat resistance as a carrier for a hydrogen generation reaction catalyst.

The carrier (CON) of the present invention is a porous organic structure, and has excellent gas adsorption ability by stably adsorbing hydrogen gas. In addition, due to the regularly arranged nitrogen atoms included in the carrier CON, adsorption and desorption of hydrogen gas can be efficiently performed.

The carrier (CON) of the present invention may include cage-type voids, and metal atoms are supported in the cage-like voids of the carrier (CON) to form a catalyst composite.

Cage-type pores of the present invention are pores formed in a carrier (CON) formed as a result of growth with symmetry in three directions as monomer b adheres to the edge of monomer a, and is tightly fixed by surrounding metal atoms in all directions. It is a void that can be made.

The cage-type voids of the present invention form nuclei of metal atoms in the process of refluxing a metal precursor, thereby providing an anchoring site for carrying the metal atoms on the carrier CON in a uniform distribution.

In addition, since the cage-like voids of the present invention contain nitrogen, metal atoms can be more rigidly fixed. Preferably, in order to more rigidly fix the metal atoms in the cage-like voids of the carrier, the cage-like voids may contain more nitrogen. In order to contain more nitrogen in the cage-like pores, the monomer a and the monomer b, which are monomers of the carrier (CON), may have one or more carbons of the ring substituted with nitrogen.

Metal atom

The metal atom of the present invention is supported on the carrier (CON) of the present invention, and thus a catalyst complex in which the metal atom is supported on the carrier (CON) may be formed.

The metal atom of the present invention may include a metal generally used in a hydrogen generation reaction catalyst in its configuration. Hereinafter, examples of the metal atoms of the present invention are listed, but are not necessarily limited thereto. Metal atoms of the present invention are iridium (Ir), cerium (Ce), iron (Fe), rhodium (Rh), palladium (Pd), comalt (Co), nickel (Ni), gold (Au), silver (Ag ), manganese (Mn), zinc (Zn), copper (Cu), and molybdenum (Mo) may include at least one selected from the group consisting of.

The metal atom of the present invention may be formed by refluxing a metal precursor. The metal precursors form nuclei of metal atoms while refluxing in the cage-like voids of the carrier CON, and as a result, the metal atoms can be supported in the cage-like voids of the carrier with uniform distribution.

Catalyst complex

The catalyst composite of the present invention may be a catalyst composite in which a metal atom is supported on a carrier (CON). 3A to 3C are plan views as viewed from various angles of the catalyst composite of the present invention. 3A is a plan view as viewed from the x, y, and z axes of the amount of the catalyst composite of the present invention. 3B is an x-y plan view of the catalyst composite of the present invention. 3C is a y-z plan view of the catalyst composite of the present invention.

Referring to FIGS. 3A to 3C, it can be seen a form in which a metal atom is supported in the cage-like voids of the carrier CON of the present invention. The catalyst composite of the present invention supports a metal atom in the cage-like voids of the carrier (CON). The carrier CON provides a cage-like void surrounding the outer surface of the metal atom. Cage-type voids form nuclei of metal atoms in the process of refluxing the metal precursor, so that the metal atoms can be supported in a uniform distribution on the carrier. Since the metal atoms are uniformly distributed and supported on the carrier (CON), and the cage-type pores contain nitrogen to strongly fix the metal atoms, the catalyst composite of the present invention has excellent catalytic activity and stability.

In addition, the catalyst composite of the present invention is advantageous in adsorption and desorption of hydrogen gas by supporting metal atoms on the porous support (CON), and thus has excellent performance as a catalyst for hydrogen evolution. Hereinafter, a method for producing the catalyst composite of the present invention will be described.

<Method for producing the catalyst composite of the present invention>

The method for preparing the catalyst composite of the present invention comprises: a) dissolving a metal precursor, 1 to 99 mol% of monomer a and 1 to 99 mol% of monomer b in an organic solvent; And b) obtaining a precipitate by adding a reducing agent to the solution in step a).

Hereinafter, each step of the method for producing a catalyst composite according to the present invention will be described in detail.

a) step: metal precursor, 1 to 99 mol% Monomers a and 1 to 99 mol% Dissolving monomer b in an organic solvent;

The metal precursor of the present invention may include a metal generally used for a hydrogen generation reaction catalyst in its configuration. Hereinafter, metals that may be included in the metal precursor of the present invention are listed, but the present invention is not limited thereto. Metal precursors of the present invention are iridium (Ir), cerium (Ce), iron (Fe), rhodium (Rh), palladium (Pd), comalt (Co), nickel (Ni), gold (Au), silver (Ag ), manganese (Mn), zinc (Zn), copper (Cu), and molybdenum (Mo) may include at least one metal selected from the group consisting of.

The metal precursor of the present invention is not limited in its constitution as long as it can be dissolved in an organic solvent as a salt of the metal described above. Hereinafter, salts of metals that may be included in the metal precursor of the present invention are listed, but are not necessarily limited thereto. The metal precursor of the present invention may further include one or more selected from the group consisting of the above-described metal fluoride, chloride, nitrate, sulfate, ammonium salt, acetate, and carbonate.

In step a) of the present invention, 1 to 99 mol% of monomer a and 1 to 99 mol% of monomer b may be dissolved in an organic solvent, but preferably, monomer a and monomer b are 1:2 to 2:1 It can be dissolved in a molar ratio of

In step a) of the present invention, the metal precursor, the monomer a and the monomer b may be dissolved in the solvent, and the composition of the solvent is not limited. As an example of the solvent of the present invention, N,N-dimethylformamide (N,N-dimethylforamide, DEF), N,N-dimethylacetamide (N,N-dimethylacetamide, DMAC), dimethylsulfoxide, DMSO), hexamethylphosphoramide (HMPA), and N-methylpyrrolidone (NMP).

Reflux may be performed at 150 to 200°C between step a) and step b) of the present invention. Reflux can be made for 2 to 5 hours. It may further include the step of cooling to 70 ~ 90 ℃ after reflux.

In step a) of the present invention, the monomer a and the monomer b may form a carrier (CON) through an irreversible reaction, and the carbonyl group or amine group of the monomer a and the monomer b undergoes a Schiff base reaction. It can be cyclized through an imine bond.

b) Step: Step a) to obtain a precipitate by adding a reducing agent to the solution

In the present invention, step b) may be a step of obtaining a precipitate by adding a reducing agent to the solution of step a). In step b), a precipitate which is a catalyst complex in which a metal atom is supported on a carrier (CON) can be obtained. Hereinafter, each configuration of step b) will be described.

In step b) of the present invention, the composition is not limited on the premise that the reducing agent can form metal nanoparticles by refluxing the metal precursor. Examples of the reducing agent include lithium borohydride (LiBH ₄ ), lithium aluminum hydride (LiAlH ₄ ), sodium borohydride (NaBH ₄ ), or hydrazine. Sodium borohydride (NaBH ₄ ) is preferably used.

The reflux of step b) of the present invention may be performed at 150 to 200° C. for 2 to 4 hours. It may further include the step of cooling to 20 ~ 30 ℃ after reflux.

The catalyst composite, which is the precipitate of step b) of the present invention, can be obtained by filtration using a polytetrafluoroethylene (PTFE) membrane before heat treatment. After the filtering process, as an example of the present invention, a process of removing impurities and low molecular weight substances by Soxhlet extraction with acetone and methanol solvents for 2 to 4 days, respectively, may be further included. The obtained final products can be removed from the solvent using a lyophilization method.

After step b) of the present invention, it may further include a step of heat treatment for 1 to 3 hours at 700 ~ 900 ℃ in an inert gas atmosphere.

In step b) of the present invention, the metal precursor is refluxed and supported on the carrier CON as a metal atom. The cage-like voids of the carrier (CON) provide an anchoring site to form a nucleus of metal atoms in the process of refluxing the metal precursor, so that the metal atoms can be supported on the carrier (CON) with a uniform distribution. do.

1 is a simplified diagram summarizing the manufacturing process of the catalyst composite of the present invention. Referring to FIG. 1, a carrier (CON ) Is synthesized. The metal precursor may be refluxed to a metal atom with a reducing agent. The cage-type pores of the carrier CON of the present invention form nuclei of metal atoms during the reflux process of the metal precursor, so that the metal atoms can be supported on the carrier CON in a uniform distribution. As an example of the present invention, the final product may be a catalyst complex in which a metal atom is supported on a carrier (CON) on the right of the arrow in FIG. 1.

{Example}

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, this is provided so that those skilled in the art can easily implement the present invention, and the present invention may be implemented in various different forms, and the spirit of the present invention is necessarily limited to the embodiments. no.

Example 1: Preparation of catalyst composite (Ir@CON)

In a nitrogen atmosphere, iridium chloride (IrCl3, 1.5g) and 70 ml of N-methylpyrrolidone (NMP) are mixed in a flask installed in an ice bucket. To the stirred solution, triptycene hexaamine hexahydrochloride (THA, 2 g) and hexaketocyclohexane octahydrate (HKH, 1.108 g) were added. Raise the temperature to room temperature, stir continuously for 2 hours, and then replace it with an oil tank to raise the temperature. After slowly raising the temperature to 175°C, the mixture was stirred for 3 hours. After the polymer reaction is over, cool to 80° C., and slowly drop a sodium borohydride solution (NaBH4, 60 ml, 10 wt% in NMP). The mixture was again raised to 175°C, stirred for 3 hours, cooled to room temperature, and poured into acetone to precipitate. The black precipitates are filtered with an appropriate filter paper, and impurities and low molecular weight substances are removed in a Soxhlet extractor for 3 days each with acetone and methanol solvents. The collected final products are subjected to a lyophilization method to remove the solvent and heat treatment in an inert gas atmosphere within the range of 700-900°C for 2 hours.

Comparative Example 1: Preparation of graphene/iridium catalyst (Ir/C)

It is a graphene/iridium (Ir) catalyst in which iridium (Ir) is supported on carbon black. Iridium was supported by 20% by weight based on the total weight of the graphene/iridium (Ir) catalyst.

Comparative Example 2: Preparation of graphene/platinum catalyst (Pt/C)

It is a graphene/platinum (Pt) catalyst in which platinum (Pt) is supported on carbon black. Platinum was supported in 20% by weight based on the total weight of the graphene/platinum (Pt) catalyst.

<Physical Characteristic Analysis>

4A and 4B are SEM (Scanning Electron Microscopy) images of Example 1 in which scale bars are 2 μm and 0.5 μm, respectively. 4A and 4B, the catalyst composite of Example 1 of the present invention has a diameter of approximately 0.8 to 2 μm in a spherical shape.

5 is an X-ray diffraction pattern (XRD) of Example 1. FIG. By comparing the peak of PDF #06-0598 (Iridium (Ir) JCPDS Card No.06-0598) and the X-ray diffraction pattern of Example 1, it can be seen that iridium (Ir) is supported on the catalyst composite of Example 1 . In addition, when the Scherrer equation is used, the average particle diameter of supported iridium (Ir) is about 2.0 nm.

6 is a nitrogen-adsorption-desorption isotherm of Example 1. 6, the Brunauer-Emmett-Teller (BET) surface of Example 1 is about 193.4 m ² /g, has a total pore volume of about 110 cm ³ /g, and has an average diameter of about 2.29 nm. Includes.

7 is a graph of pore size distribution in Example 1. Referring to FIG. 7, it can be seen that the pore size distribution of Example 1 has one major peak around 0.82 nm.

8 is an Atomic-resolution transmission electron microscopy (AR-TEM) image of Example 1 (scale bar: 4 nm). Referring to FIG. 8, the average particle diameter of iridium (Ir) is about 1.3 to 2.3 nm, and the specific surface area value of Example 1 is about 193.36 m ² /g.

9 is a scanning transmission electron microscopy image (HAADF (high-angle annular dark field) image and EDX (energy dispersive X-ray spectroscopy) image (C (carbon ), Ir (iridium), N (nitrogen)) (scale bar: 10 nm). Referring to FIG. 9, it can be seen that iridium (Ir) is uniformly supported on the carrier CON.

Confirmation of structural properties of Example 1-Analysis of measurement results

4A, 4B, 5, and 8, Example 1 (Ir@CON) of the present invention has a diameter of approximately 0.8 to 2 μm in a spherical shape. In Example 1, iridium (Ir) is supported, and the average particle diameter of the supported iridium (Ir) is about 1.3 to 2.3 nm.

6, 7, and 8, the specific surface area value of Example 1 (Ir@CON) of the present invention is about 193.4 m ² /g. In addition, the total pore volume is about 110 cm ³ /g, the average pore diameter is about 2.29 nm, and the center of the main peak of the pore size distribution is about 0.82 nm.

Referring to FIG. 9, it can be seen that the iridium (Ir) supported in Example 1 of the present invention is uniformly supported on the carrier (CON), and thus Example 1 has excellent catalytic activity and stability.

<Electrochemical Characteristics Analysis-Hydrogen Generation Performance Analysis>

Electrochemical activity and stability were measured in the electrode cell using a rotating disk electrode (RDE) equipped with a potential stat. An Ag/AgCl (3.0M aq. NaCl) electrode and a graphite rod were used as a reference electrode and a counter electrode, respectively, and a rotating disk electrode loaded with each catalyst material was used as a working electrode. For the electrochemical test, 5 mg catalyst and 10 μl Nafion solution were subjected to ultrasonic treatment to form a homogeneous ink in 1 mL water and an analytical grade ethanol (v/v, 1/1) solution. The prepared electrode catalyst suspension (10 µl) was placed on a rotating disk electrode (RDE) having an area of 0.196 cm ^-2 (loading amount -0.50 mg/cm ² ), and then dried at room temperature before electrochemical testing.

Polarization curve

Figure 10a is a polarization curve for the hydrogen reduction reaction of Example 1 and each comparative example in an acidic environment (pH 0 ~ 0.3) (a sulfuric acid solution 0.5M, scan rate 5mV/s). In FIG. 10A, the polarization curves of Example 1 and each of the comparative examples are shown compared to a reversible hydrogen potential (RHE). In the graph of FIG. 10A, the horizontal axis represents the potential (V (vs RHE)), and the vertical axis represents the current density (mA/cm ² ). 10B is an enlarged graph of FIG. 10A.

The catalytic activity of Example 1 and each of the comparative examples can be compared from the value of the potential (V (vs RHE)) to produce a current density (mA/cm ² ) of the same size in FIGS. 10A and 10B. 10A and 10B, if the catalytic activity is sorted in the order of excellent catalytic activity, it can be sorted in the order of Example 1, Comparative Example 2, and Comparative Example 1.

11A is a polarization curve graph for the hydrogen reduction reaction of Example 1 and each of the comparative examples in a basic environment (pH 14) (a solution of potassium hydroxide 1.0M, a scan speed of 5mV/s). In FIG. 11A, the polarization curves of Example 1 and each of the comparative examples are shown compared to a reversible hydrogen potential (RHE). In the graph of FIG. 11A, the horizontal axis represents the potential (V (vs RHE)), and the vertical axis represents the current density (mA/cm ² ). 11B is an enlarged graph of FIG. 11A.

The catalytic activity of Example 1 and each of the comparative examples can be compared from the value of the potential (V (vs RHE)) to produce a current density (mA/cm ² ) of the same size in FIGS. 11A and 11B. 11A and 11B, if the catalytic activity is sorted in the order of excellent catalytic activity, it can be sorted in the order of Example 1, Comparative Example 2, and Comparative Example 1.

Tafel slope

10C shows a Tafel slope graph of Example 1 and each of the comparative examples from the results of FIG. 10A (acid environment, pH 0 to 0.3). The Tafel slope is the criterion of the electrode activity and represents the voltage required to increase the current 10 times. In the graph of FIG. 10C, the horizontal axis represents the logarithmic scale of the current density (mA/cm ² ), and the vertical axis represents the potential (V(vs RHE)).

Referring to FIG. 10C, the Tapel slope of Example 1 was measured to be about 27mV/decade. Tapel slopes of Comparative Example 1 and Comparative Example 2 were measured as about 30mV/decade and 29mV/decade, respectively.

The Tafel slope value of Example 1 is a lower value compared to Comparative Examples 1 and 2, and it can be seen that Example 1 has excellent catalytic activity compared to each of Comparative Examples.

11C shows a Tafel slope graph of Example 1 and each of the comparative examples from the results of FIG. 11A (basic environment, pH 14). The Tafel slope is the criterion of the electrode activity and represents the voltage required to increase the current 10 times. In the graph of FIG. 11C, the horizontal axis is the logarithmic scale of the current density (mA/cm ² ), and the vertical axis is the potential (V(vs RHE)).

Referring to FIG. 11C, the Tafel slope of Example 1 was measured to be about 29mV/decade. Tapel slopes of Comparative Example 1 and Comparative Example 2 were measured as about 32mV/decade and 37mV/decade, respectively.

The Tafel slope value of Example 1 is a lower value compared to Comparative Examples 1 and 2, and it can be seen that Example 1 has excellent catalytic activity compared to each of Comparative Examples.

Overvoltage and exchange current density

10D is a graph comparing the overvoltage (mV) and the exchange current density (mA/cm ² ) of Example 1 and each of the comparative examples from the results of FIG. 10A (acid environment, pH 0 to 0.3). In the graph of FIG. 10D, the horizontal axis represents Example 1 and each comparative example, the vertical axis on the left is the overvoltage (mV, calculation point: 10mA/cm ² ), and the vertical axis on the right is the exchange current density (mA/cm ² ).

Referring to the left vertical axis of FIG. 10D, the overvoltages of Example 1, Comparative Example 1, and Comparative Example 2 are about 13.4 mV (vs RHE), 20.2 mV (vs RHE), and 17.8 mV (vs RHE), respectively. From the above results, it can be seen that the overvoltage of Example 1 is a lower value compared to Comparative Examples 1 and 2, and that Example 1 has less power loss during hydrogen generation reaction compared to each of Comparative Examples.

In addition, referring to the right vertical axis of FIG. 10D, the exchange current density (mA/cm ² ) of Example 1, Comparative Example 1 and Comparative Example 2 is about 1.15 mA/cm ² , 0.76 mA/cm ² _{, and} 0.51 mA/ cm ² From the above results, it can be seen that the exchange current density of Example 1 is higher than that of Comparative Examples 1 and 2, and Example 1 has more electron exchange than each of Comparative Examples, so that hydrogen generation reaction occurs well.

It can be seen from FIG. 10D that the catalytic activity of Example 1 is superior to that of Comparative Examples 1 and 2.

11D is a graph comparing the overvoltage (mV) and the exchange current density (mA/cm ² ) of Example 1 and each of the comparative examples from the results of FIG. 11A (basic environment, pH 14). In the graph of FIG. 11D, the horizontal axis represents Example 1 and each comparative example, the vertical axis on the left is the overvoltage (mV, calculation point: 10mA/cm ² ), and the vertical axis on the right is the exchange current density (mA/cm ² ).

Referring to the left vertical axis of FIG. 11D, the overvoltages in Example 1, Comparative Example 1, and Comparative Example 2 are about 12.9 mV (vs RHE), 28.3 mV (vs RHE), and 22.5 mV (vs RHE), respectively. From the above results, it can be seen that the overvoltage of Example 1 is a lower value compared to Comparative Examples 1 and 2, and that Example 1 has less power loss during hydrogen generation reaction compared to each of Comparative Examples.

In addition, referring to the right vertical axis of FIG. 11D, the exchange current density (mA/cm ² ) of Example 1, Comparative Example 1 and Comparative Example 2 is about 1.40 mA/cm ² , 0.66 mA/cm ² _{, and} 1.29 mA/ cm ² From the above results, it can be seen that the exchange current density of Example 1 is higher than that of Comparative Examples 1 and 2, and Example 1 has more electron exchange than each of Comparative Examples, so that hydrogen generation reaction occurs well.

It can be seen from FIG. 11D that the catalytic activity of Example 1 is superior to that of Comparative Examples 1 and 2.

10,000 hydrogen generation tests

10E is a graph of polarization curves for hydrogen reduction reactions of Example 1 and Comparative Examples after 10,000 hydrogen generation tests in an acidic environment (pH 0 to 0.3). (Sulfuric acid aqueous solution 0.5M, scan rate: 5mV/s) In FIG. 10e, the initial curve is the polarization curve of the catalyst that has not been tested for hydrogen generation, and the 10,000 cycles curve is the polarization curve of the catalyst that has undergone 10,000 hydrogen generation tests. In FIG. 10E, the horizontal axis represents the potential (V (vs RHE)), and the vertical axis represents the current density (mA/cm ² ).

The catalytic activity of Example 1 and each of the comparative examples can be compared from the value of the potential (V(vs RHE)) to produce the same-sized current density (mA/cm ² ). That is, after the hydrogen generation test on the graph, the polarization curve moves to the left, and the higher the value of the potential (V(vs RHE)) for producing the same size current density (mA/cm ² ), the more catalytic activity becomes. It can be seen that it fell. It can be interpreted that the higher the degree of decrease in catalytic activity, the lower the catalytic activity stability.

In FIG. 10E, the initial polarization curve of Example 1 is located to the right of the initial polarization curves of Comparative Examples 1 and 2, and it can be seen that Example 1 has better catalytic activity than each Comparative Example in an acidic environment. In addition, the 10,000 cycles polarization curve of Example 1 almost coincides with the initial polarization curves of Comparative Examples 1 and 2 even though the hydrogen generation test was carried out, and the catalytic activity of Example 1 in an acidic environment was found in Comparative Examples 1 and 2 It can be seen that it is far superior. From FIG. 10E, it can be seen that Example 1 exhibits superior catalytic activity in an acidic environment than Comparative Examples 1 and 2 even when the hydrogen generation reaction occurs repeatedly.

In addition, since the gap between the initial polarization curve of Example 1 and the 10,000 cycles polarization curve in FIG. 10E is much smaller than the gap between the initial polarization curve of Comparative Example 2 and the 10,000 cycles polarization curve, the catalytic activity stability of Example 1 in an acidic environment It can be seen that it is superior to Comparative Example 2.

10F is an image for confirming that the structure of Example 1 is stably maintained after the hydrogen generation test of FIG. 10E. 10F is a high-angle annular dark field (HAADF) image and EDX (energy dispersive X-) of Example 1, each of which was subjected to a hydrogen generation test of 10,000 times sequentially from the left in a scanning transmission electron microscopy image. ray spectroscopy) images (C (carbon), Ir (iridium), N (nitrogen)) (scale bar: 200 nm).

Referring to FIG. 10F, it can be seen that iridium (Ir) is uniformly supported on the carrier (CON) even after 10,000 hydrogen generation tests in an acidic environment, so that the catalyst complex of Example 1 is repeatedly subjected to hydrogen generation reaction. It can be seen that the catalytic activity is stably maintained even when it occurs.

11E is a graph of polarization curves for hydrogen reduction reactions of Example 1 and Comparative Examples after 10,000 hydrogen generation tests in a basic environment (pH 14). (Potassium hydroxide aqueous solution 1.0M, scan rate: 5mV/s) In FIG. In FIG. 11E, the horizontal axis represents the potential (V (vs RHE)), and the vertical axis represents the current density (mA/cm ² ).

The catalytic activity of Example 1 and each of the comparative examples can be compared from the value of the potential (V(vs RHE)) to produce the same-sized current density (mA/cm ² ). In other words, after the hydrogen generation test on the graph, the polarization curve moves to the left, and the higher the value of the potential (V(vs RHE)) to produce the same size current density (mA/cm ² ), the more catalytic activity becomes. It can be seen that it fell. It can be interpreted that the greater the degree to which the catalytic activity falls, the lower the catalytic activity stability is.

In FIG. 11E, the initial polarization curve of Example 1 is located to the right of the initial polarization curves of Comparative Examples 1 and 2, and it can be seen that Example 1 has better catalytic activity than each Comparative Example in a basic environment. In addition, the 10,000 cycles polarization curve of Example 1 was located to the right of the initial polarization curves of Comparative Examples 1 and 2 even though the hydrogen generation test was performed, so that the catalytic activity of Example 1 in a basic environment was found in Comparative Examples 1 and Comparative Examples. It can be seen that it is far superior to 2. From FIG. 11E, it can be seen that Example 1 exhibits superior catalytic activity in a basic environment than Comparative Examples 1 and 2 even when the hydrogen generation reaction occurs repeatedly.

In addition, since the gap between the initial polarization curve of Example 1 and the 10,000 cycles polarization curve of Example 1 in FIG. 11E is much smaller than the gap between the initial polarization curve of Comparative Examples 1 and 2 and the 10,000 cycles polarization curve, It can be seen that the catalytic activity stability is better than that of Comparative Example 1 and Comparative Example 2.

11F is an image for confirming that the structure of Example 1 is stably maintained after the hydrogen generation test of FIG. 11E. 11F is a high-angle annular dark field (HAADF) image and EDX (energy dispersive X-) of Example 1, each subjected to a hydrogen generation test of 10,000 times sequentially from the left in a scanning transmission electron microscopy image. ray spectroscopy) images (C (carbon), Ir (iridium), N (nitrogen)) (scale bar: 200 nm).

Referring to FIG. 11F, it can be seen that iridium (Ir) is uniformly supported on the carrier (CON) even after 10,000 hydrogen generation tests in a basic environment, so that the catalyst complex of Example 1 is repeatedly subjected to a hydrogen generation reaction. It can be seen that it remains stable even when it occurs.

Comparison of catalyst performance with known catalysts

10g is a table for comparing overvoltages of Example 1 and Comparative Examples 1 and 2, and known catalysts in an acidic environment (pH 0 to 0.3) (aqueous sulfuric acid solution of 0.5M).

Referring to FIG. 10G, it can be seen that Example 1 has the lowest overvoltage among the catalysts listed in the table, and thus the power loss is the least during hydrogen generation reaction.

10H is a table for comparing the overvoltage and Turnover Frequency (TOF) of Example 1 and Comparative Examples 1 and 2, and known hydrogen generation reaction catalysts in an acidic environment (pH 0 to 0.3) (sulfuric acid aqueous solution 0.5M). The vertical axis of FIG. 10H represents TOF (H ₂ /s), which is the production amount of hydrogen molecules at the active site per second, and the horizontal axis represents the overvoltage (V). The lower the overvoltage (V), the less power consumption for the hydrogen generation reaction is, and the higher the TOF value, the better the catalytic activity for the hydrogen generation reaction.

The voltage at 25mV, in Example 1, a value of the TOF of Comparative Examples 1 and 2 is about 0.66H ₂ / s, 0.91H ₂ / s, 0.67H do not differ significantly as ₂ / s, respectively, the catalyst of Example 1 It can be seen that the activity is similar to that of Comparative Example 1 and Comparative Example 2. In addition, it can be seen from FIG. 10H that Example 1 is located on the right side compared to the known hydrogen generation reaction catalysts, and thus the overvoltage is small, so that the power consumption is small.

From FIGS. 10G and 10H above, it can be seen that the catalytic performance of Example 1 is superior to that of Comparative Examples 1 and 2 and known hydrogen generation reaction catalysts because the overvoltage is small and the TOF value is large.

11G is a table for comparing overvoltages of Example 1 and Comparative Examples 1 and 2 and known catalysts in a basic environment (pH 14) (aqueous potassium hydroxide solution of 1.0M).

Referring to FIG. 11G, it can be seen that Example 1 has the lowest overvoltage among the catalysts listed in the table, and thus the power loss during hydrogen generation reaction is the least.

11H is a table for comparing the overvoltage and turnover frequency (TOF) of Example 1 and Comparative Examples 1 and 2, and known hydrogen generation reaction catalysts in a basic environment (pH 14) (aqueous potassium hydroxide solution of 1.0M). The vertical axis of FIG. 11H represents TOF (H ₂ /s), which is the production amount of hydrogen molecules at the active site per second, and the horizontal axis represents the overvoltage (V). The lower the overvoltage (V), the less power consumption for the hydrogen generation reaction is, and the higher the TOF value, the better the catalytic activity for the hydrogen generation reaction.

The voltage at 25mV, in Example 1, a value of the TOF of Comparative Examples 1 and 2 is about 0.20H ₂ / s, 0.24H ₂ / s, 0.25H do not differ significantly as ₂ / s, respectively, the catalyst of Example 1 It can be seen that the activity is similar to that of Comparative Example 1 and Comparative Example 2. In addition, it can be seen from FIG. 11H that Example 1 has a lower overvoltage and a higher TOF value than that of known hydrogen generation reaction catalysts, so that the catalytic activity of Example 1 is excellent.

From FIGS. 11G and 11H above, it can be seen that Example 1 has a low overvoltage and a large TOF value, so that the catalyst performance is superior to that of Comparative Examples 1 and 2 and known hydrogen generation reaction catalysts.

<Evaluation of Example 1 and each comparative example>

Catalyst activity

Referring to FIG. 9, it can be seen that the iridium (Ir) supported in Example 1 of the present invention is uniformly supported on the carrier (CON), and thus the catalyst composite of the present invention has excellent catalytic activity.

10A to 10D, the catalytic activity of Example 1 in an acidic environment (pH 0 to 0.3) is better than that of each comparative example (0.5M sulfuric acid aqueous solution). From this, it can be seen that the catalyst composite of the present invention has excellent catalytic activity in an acidic environment.

11A to 11D, the catalytic activity of Example 1 in a basic environment (pH 14) is better than that of the comparative example (aqueous potassium hydroxide solution of 1.0 M). From this, it can be seen that the catalyst complex of the present invention has excellent catalytic activity in a basic environment.

When comparing the results of FIGS. 10A to 10D in an acidic environment and FIGS. 11A to 11D in a basic environment, the catalytic activity of Example 1 is superior to Comparative Examples 1 and 2 in both acidic and basic environments. From this, it can be seen that the catalytic activity of the catalyst composite of the present invention is excellent in a wide range of pH.

In addition, referring to FIG. 10G, since the overvoltage of Example 1 in the acidic environment (pH 0 to 0.3) is low and the TOF value is large, the catalyst performance is superior compared to Comparative Examples 1 and 2 and known hydrogen generation reaction catalysts. Can be seen (0.5M sulfuric acid aqueous solution).

Referring to FIG. 11G, it can be seen that the catalytic performance of Example 1 in a basic environment (pH 14) is low and the TOF value is large, so that the catalyst performance is superior to that of Comparative Examples 1 and 2 and known hydrogen generation reaction catalysts. (1.0M potassium hydroxide aqueous solution).

Referring to FIGS. 10G and 11G, in both acidic and basic environments, since Example 1 has a low overvoltage and a large TOF value, the catalyst performance is in a broader pH range compared to Comparative Examples 1 and 2 and known hydrogen generation reaction catalysts. You can see excellence in

Catalyst activity stability

10E is a polarization curve graph for the hydrogen reduction reaction of Example 1 and Comparative Examples after 10,000 hydrogen generation tests in an acidic environment (pH 0 to 0.3) (sulfuric acid aqueous solution 0.5M). 10F is an image for confirming that the structure of Example 1 is stably maintained after the hydrogen generation test of FIG. 10E. It is the HAADF image and the EDX image (C,Ir,N) of Example 1, each of which was tested 10,000 times in order from the left.

Referring to FIG. 10E, since the gap between the initial polarization curve of Example 1 and the 10,000 cycles polarization curve is smaller than that of each comparative example, it can be seen that the catalytic activity stability is excellent.

Referring to FIG. 10F, it can be seen that iridium (Ir) is uniformly supported on the carrier CON even after 10,000 hydrogen generation tests.

Referring to FIGS. 10E and 10F, in Example 1, the catalytic activity is stably maintained well even when the hydrogen generation reaction occurs repeatedly. From this, it can be seen that the catalyst composite of the present invention has excellent catalytic activity stability.

11E is a polarization curve graph for the hydrogen reduction reaction of Example 1 and Comparative Examples after 10,000 hydrogen generation tests in a basic environment (pH 14) (aqueous potassium hydroxide solution of 1.0M). 11F is an image for confirming that the structure of Example 1 is stably maintained after the hydrogen generation test of FIG. 11E. It is the HAADF image and the EDX image (C,Ir,N) of Example 1, each of which was tested 10,000 times in order from the left.

Referring to FIG. 11E, since the gap between the initial polarization curve of Example 1 and the 10,000 cycles polarization curve is smaller than that of each comparative example, it can be seen that the catalytic activity stability is excellent.

Referring to FIG. 11F, it can be confirmed that iridium (Ir) is uniformly supported on the carrier CON even after 10,000 hydrogen generation tests.

Referring to FIGS. 11E and 11F, in Example 1, the catalytic activity is stably maintained well even when the hydrogen generation reaction occurs repeatedly. From this, it can be seen that the catalyst composite of the present invention has excellent catalytic activity stability.

In addition, it is important that the hydrogen generating catalyst maintains catalytic activity even in a wide pH range. When comparing the results of FIGS. 10A to 10F in an acidic environment and FIGS. 11A to 11F in a basic environment, the catalytic activity and stability of the catalytic activity of Example 1 are superior to those of Comparative Examples 1 and 2 in both acidic and basic environments. From this, it can be seen that the catalytic activity stability of the catalyst composite of the present invention is excellent in a wide pH range.

Claims (16)

A carrier comprising 1 to 99 mol% of monomer a represented by the following general formula (1) and 1 to 99 mol% of monomer b represented by the following general formula (3); And a catalyst complex for hydrogen generation comprising a metal atom:
[General Formula (1)]

[General Formula (3)]

In the general formulas (1) and (3), Ra ₁ to Ra ₆ and Rb ₁ to Rb ₆ are each carbon (C),
In the general formula (1), X ₁ to X ₆ are each independently selected from an oxygen or amine group,
In the general formula (3), Y ₁ to Y ₆ are each independently selected as an oxygen or amine group on the premise of forming an imine bond with X ₁ to X ₆ (when X _{A and} Y _A are oxygen, R _aA -X _A , R _bA -Y _A is a carbonyl group, and A is a natural number of 1 to 6 or less).
The method of claim 1,
In the general formula (1), X ₁ to X ₆ are all selected from oxygen or amine groups,
In the general formula (3), Y ₁ to Y ₆ are all dependently selected from oxygen or amine groups on the premise of forming an imine bond with X ₁ to X ₆ .
The method of claim 1,
The support is a catalyst composite for hydrogen generation, characterized in that it comprises a cage-like void formed by repeatedly reacting the monomer a and the monomer b.
The method of claim 1,
The metal atoms are iridium (Ir), cerium (Ce), iron (Fe), rhodium (Rh), palladium (Pd), comalt (Co), nickel (Ni), gold (Au), silver (Ag), Manganese (Mn), zinc (Zn), copper (Cu) and molybdenum (Mo) at least one selected from the group consisting of a catalyst composite for hydrogen generation.
The method according to any one of claims 1 to 4,
A catalyst composite for hydrogen generation, characterized in that the catalytic activity is maintained at a pH concentration of 0 or more and 14 or less.
a) dissolving a metal precursor, 1 to 99 mol% of monomer a represented by the following general formula (1) and 1 to 99 mol% of a monomer b represented by the following general formula (3) in an organic solvent;
b) adding a reducing agent to the solution in step a) to obtain a precipitate; method for producing a catalyst composite for generating hydrogen comprising:
[General Formula (1)]

[General Formula (3)]

In the general formulas (1) and (3), Ra ₁ to Ra ₆ and Rb ₁ to Rb ₆ are each carbon (C),
In the general formula (1), X ₁ to X ₆ are each independently selected from an oxygen or amine group,
In the general formula (3), Y ₁ to Y ₆ are each independently selected as an oxygen or amine group on the premise of forming an imine bond with X ₁ to X ₆ (when X _{A and} Y _A are oxygen, R _aA -X _A , R _bA -Y _A is a carbonyl group, and A is a natural number of 1 to 6 or less).
The method of claim 6,
The metal precursor in step a) is iridium (Ir), cerium (Ce), iron (Fe), rhodium (Rh), palladium (Pd), comalt (Co), nickel (Ni), gold (Au), Silver (Ag), manganese (Mn), zinc (Zn), copper (Cu) and molybdenum (Mo), characterized in that it comprises at least one metal selected from the group consisting of a method for producing a catalyst composite for hydrogen generation.
The method of claim 6,
The monomer a and the monomer b in step a) are dissolved in a molar ratio of 1:2 to 2:1.
The method of claim 6,
The organic solvent in step a) is N,N-dimethylformamide (N,N-dimethylforamide, DEF), N,N-dimethylacetamide (N,N-dimethylacetamide, DMAC), dimethylsulfoxide. , DMSO), hexamethylphosphoramide (HMPA), and N-methylpyrrolidone (NMP). A method for producing a catalyst complex for hydrogen generation, comprising at least one from the group consisting of.
The method of claim 6,
The reducing agent of step b) for generating hydrogen, characterized in that it contains at least one from the group consisting of lithium borohydride (LiBH ₄ ), lithium aluminum hydride (LiAlH ₄ ), sodium borohydride (NaBH ₄ ) or hydrazine Method for producing a catalyst composite.
The method of claim 6,
In step b), the precipitate is obtained by filtration using a polytetrafluoroethylene (PTFE) membrane.
The method of claim 6,
A method for producing a catalyst composite for hydrogen generation, characterized in that reflux is performed in step b).
The method according to any one of claims 6 to 12,
A method of producing a catalyst composite for hydrogen generation, further comprising a step of refluxing at 150 to 200°C between steps a) and b).
The method of claim 13,
After step b), heat-treating at 700 to 900° C. for 1 to 3 hours in an inert gas atmosphere.
The method of claim 1,
The monomer a is triptycene hexaamine hexahydrochloride (THA) represented by the following formula (1),
The monomer b is a catalyst complex for hydrogen generation, characterized in that hexaketocyclohexane octahydrate (HKH) represented by the following formula (2).
[Formula (1)]

[Formula (2)]

The method of claim 6,
The monomer a is triptycene hexaamine hexahydrochloride (THA) represented by the following formula (1),
The monomer b is hexaketocyclohexane octahydrate (HKH) represented by the following formula (2).
[Formula (1)]

[Formula (2)]

Images