Catalyst for chlorine evolution reaction, catalyst structure for chlorine evolution reaction, and method for manufacturing catalyst for chlorine evolution reaction

Abstract

A catalyst for a chlorine evolution reaction, according to an embodiment of the present invention, comprises: nanoparticles including cobalt oxide having a composition formula of CoxO1-x (0.33 < x < 0.50); and transition metal particles including at least one from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt) and palladium (Pd), which are present on the surface of the nanoparticles.

Description

Catalyst for chlorine generation reaction, catalyst structure for chlorine generation reaction, and method for producing catalyst for chlorine generation reaction

[0001] The present invention relates to a catalyst for a chlorine generation reaction, a catalyst structure for a chlorine generation reaction, and a method for producing a catalyst for a chlorine generation reaction, and more particularly, to a catalyst for a chlorine generation reaction comprising cobalt oxide nanoparticles, a catalyst structure for a chlorine generation reaction comprising the catalyst, and a method for producing the catalyst for the chlorine generation reaction.

[0002] Chlorine is a key raw material used in diverse fields, including plastics, chemical materials, pulp production, and water disinfection, and is a chemical raw material with a massive global market. In particular, the recently adopted Ballast Water Management Convention is expected to revitalize the ballast water treatment market, fueled by increased international demand and interest in ballast water treatment systems. Chlorine-based ballast water treatment is expected to dominate the global ballast water treatment market, highlighting the importance of chlorine production.

[0003] The chlorine currently produced industrially is obtained by electrochemically oxidizing brine. Because the chlorine oxidation reaction competes with the oxygen evolution reaction, a water oxidation reaction, the development of a catalyst that simultaneously suppresses the oxygen evolution reaction and promotes the chlorine oxidation reaction is essential for efficient and stable chlorine production.

[0004] [Prior Art Document]: (Patent Document 1) Korean Patent Publication No. 10-2017-7014187

[0005] One of the technical tasks to be achieved by the technical idea of ​​the present invention is to provide a catalyst for chlorine generation reaction in which the efficiency and stability of the catalyst are secured, a catalyst structure for chlorine generation reaction including the catalyst, and a method for producing a catalyst for chlorine generation reaction.

[0006] A catalyst for chlorine generation reaction according to an embodiment of the present invention is Co x O 1-x A nanoparticle comprising cobalt oxide having a composition formula of (0.33 < x < 0.50), and a transition metal particle comprising at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), and palladium (Pd) present on the surface of the nanoparticle.

[0007] A catalyst structure for a chlorine generation reaction according to an embodiment of the present invention comprises a catalyst layer comprising a metal oxide, nanoparticles comprising cobalt oxide dispersed in the metal oxide, and transition metal particles comprising at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), and palladium (Pd).

[0008] A catalyst structure for a chlorine generation reaction according to an embodiment of the present invention comprises an intermediate layer including at least one selected from the group consisting of titanium (Ti) and tin (Sn), and a catalyst layer disposed on the intermediate layer and including nanoparticles including cobalt oxide.

[0009] A method for producing a catalyst for a chlorine generation reaction according to an embodiment of the present invention includes the steps of: dissolving an antimony (Sb) precursor in a mixed solvent of isopropyl alcohol (IPA) and water to prepare an antimony (Sb) precursor solution; dispersing a tin (Sn) precursor in the antimony (Sb) precursor solution; introducing a solution in which a ruthenium (Ru) precursor is dissolved into the antimony (Sb) and tin (Sn) precursor solutions; and introducing a solution in which nanoparticles containing cobalt oxide are dissolved in isopropyl alcohol (IPA) into the solution in which the antimony (Sb) precursor, the tin (Sn) precursor, and the ruthenium (Ru) precursor are dissolved to prepare a catalyst composition.

[0010] By including cobalt oxide nanoparticles, a catalyst for chlorine generation reaction with secured catalytic efficiency and stability can be provided.

[0011] In addition, by optimizing the structure of a catalyst structure including the catalyst, a catalyst structure for a chlorine generation reaction in which the efficiency and stability of the catalyst are secured, and a method for manufacturing the catalyst for the chlorine generation reaction can be provided.

[0012] The various advantageous and beneficial effects of the present invention are not limited to the above-described contents, and will be more easily understood in the course of explaining specific embodiments of the present invention.

[0013] FIG. 1 is a TEM image and (c) a size distribution graph of cobalt oxide nanoparticles synthesized by (a) hot injection and (b) hydrothermal synthesis according to one embodiment of the present invention.

[0014] FIGS. 2a and 2b are graphs of electron energy loss spectroscopy (EELS) analysis of a catalyst layer according to one embodiment of the present invention.

[0015] FIGS. 3A to 3C are electron micrographs of transition metals disposed on the surface or within the crystal structure of cobalt oxide nanoparticles according to one embodiment of the present invention.

[0016] FIG. 4 is a drawing showing the efficiency of a catalyst structure for a chlorine generation reaction according to one embodiment of the present invention under low salt conditions.

[0017] FIG. 5 is an electron microscope photograph of cobalt oxide nanoparticles according to one embodiment of the present invention.

[0018] FIG. 6 is a graph showing the results of X-ray diffraction analysis (XRD) of a catalyst for a chlorine generation reaction according to one embodiment of the present invention.

[0019] FIGS. 7A to 7E are schematic cross-sectional views each showing a catalyst structure for a chlorine generation reaction according to one embodiment of the present invention.

[0020] FIG. 8 is a drawing showing the chlorine generation efficiency of a catalyst structure for a chlorine generation reaction according to one embodiment of the present invention.

[0021] FIGS. 9A to 9D are EELS analysis graphs and electron microscope photographs of a catalyst layer according to one embodiment of the present invention.

[0022] Figure 10 is a schematic perspective view of an electrochemical system for chlorine generation reaction according to one embodiment of the present invention.

[0023] Figure 11 is an electron microscope photograph showing the results of surface analysis of intermediate layers according to one embodiment of the present invention.

[0024] FIG. 12 is a photograph showing the results of a mechanical stability analysis of intermediate layers in catalyst structures for a chlorine generation reaction according to one embodiment of the present invention.

[0025] FIGS. 13a and 13b are graphs showing the results of catalyst stability evaluations for catalyst structures for chlorine generation reactions according to one embodiment of the present invention.

[0026] Figures 14a to 14d are graphs showing the results of catalyst stability evaluation for catalyst structures for chlorine generation reaction according to one embodiment of the present invention.

[0027] Figure 15 is a photograph showing the acid stability of a catalyst structure for a chlorine generation reaction according to one embodiment of the present invention.

[0028] FIGS. 16a and 16b are photographs showing the results of mechanical stability analysis of catalyst layers in catalyst structures for chlorine generation reactions according to one embodiment of the present invention.

[0029] Figure 17 is a graph showing the results of a catalyst stability evaluation for catalyst structures for a chlorine generation reaction according to one embodiment of the present invention.

[0030] Figure 18 is an electron microscope photograph showing the results of surface analysis of intermediate layers according to one embodiment of the present invention.

[0031] FIG. 19 is a photograph showing the results of a mechanical stability analysis according to heat treatment conditions of a catalyst layer in catalyst structures for a chlorine generation reaction according to one embodiment of the present invention.

[0032] FIGS. 20a and 20b are graphs showing the results of evaluating the catalytic activity according to the heat treatment conditions of the catalyst layer in catalyst structures for a chlorine generation reaction according to one embodiment of the present invention.

[0033] FIGS. 21a to 21c are scanning electron microscope (SEM) photographs showing the thickness of a catalyst layer and an intermediate layer in a catalyst structure for a chlorine generation reaction according to one embodiment of the present invention.

[0034] Figures 22a to 22c are scanning electron microscope (SEM) photographs showing differences in the morphology of a catalyst layer according to heat treatment conditions in a catalyst structure for a chlorine generation reaction according to one embodiment of the present invention.

[0035] Hereinafter, preferred embodiments of the present invention will be described with reference to the attached drawings.

[0036] The embodiments of the present invention may be modified in various different forms or various embodiments may be combined, and the scope of the present invention is not limited to the embodiments described below. Furthermore, the embodiments of the present invention are provided to more completely explain the present invention to those with average knowledge in the relevant technical field. Accordingly, the shapes and sizes of elements in the drawings may be exaggerated for clarity, and elements indicated by the same reference numerals in the drawings are identical elements.

[0037] Throughout this specification, “catalyst” may mean a material that constitutes a catalyst layer and is used in a chlorine generation reaction.

[0038] Throughout the present specification, "catalyst structure" may mean a structure including a catalyst layer for a chlorine generation reaction, and may mean a structure including an intermediate layer and a metal oxide layer that may be additionally disposed below the catalyst layer.

[0039] Throughout the present specification, "catalyst layer" may mean a layer distinct from an intermediate layer and a metal oxide layer that may be additionally disposed below the catalyst layer, or may mean the entire layer including the catalyst layer, the intermediate layer, and the metal oxide layer.

[0040] Catalyst for chlorine generation reaction

[0041] A catalyst for chlorine generation reaction according to one embodiment of the present invention is Co x O 1-x The catalyst for chlorine generation reaction according to one embodiment of the present invention may further include nanoparticles comprising cobalt oxide having a composition formula of (0.33 < x < 0.50). The catalyst for chlorine generation reaction according to one embodiment of the present invention may further include transition metal particles present on the surface of the nanoparticles. The transition metal particles may include at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), and palladium (Pd). The nanoparticles may have a diameter in the range of about 5 nm to about 50 nm (Fig. 1).

[0042] The above transition metal particles may be attached to the surface of the nanoparticles with a size of about 0.1 nm to about 3 nm. Alternatively, the transition metal particles may be present within the crystal structure of the nanoparticles.

[0043] According to one embodiment of the present invention, the transition metal particles may exist in a metallic transition metal state on the surface or within the crystal structure of the nanoparticles, but not all transition metal particles exist in a metallic transition metal state, and some may exist in the form of oxides or hydroxides (Figs. 2a and 2b).

[0044] Additionally, the transition metal particles may exist in a single-atom form or a nanocluster form on the surface or within the crystal structure of the cobalt oxide nanoparticles (Figs. 3a to 3c).

[0045] The content of palladium (Pd) in the above transition metal particles may be, for example, 0.1 at% to 5.0 at%. Preferably, the content of palladium (Pd) in the above transition metal particles may be 0.2 at% to 4.0 at% or 0.3 at% to 3.0 at%, more preferably 0.1 at% to 1.0 at%, and more preferably 0.9 at%.

[0046] In the case of electrodes for chlorine generation reactions currently being commercialized, the content of palladium (Pd) is 10 at% or more, but in one embodiment of the present invention, the content of palladium (Pd) among the transition metal particles is characterized by being 5.0 at% or less.

[0047] According to one embodiment of the present invention, even if the content of palladium (Pd) among the transition metal particles is added in a small amount of 1.0 at% or less, 500 mA / cm 2 Excellent effects can be obtained, such as electrochemical long-term stability of 500 h or more at current density, chlorine generation efficiency of 95% or more under 0.6 M NaCl conditions, and chlorine generation efficiency of 80% or more under 20 mM NaCl conditions.

[0048] In particular, when the content of palladium (Pd) among the above transition metal particles is increased to 3.0 at% or less, an even better effect of chlorine generation efficiency of 95% or more under low-salt (20 mM NaCl) conditions can be obtained in addition to the above effect (Fig. 4).

[0049] FIG. 5 is an electron microscope photograph of cobalt oxide nanoparticles according to one embodiment of the present invention.

[0050] Referring to Fig. 5, Cox O 1-x Cobalt oxide nanoparticles having a composition of (0.33 < x < 0.50) were analyzed by a transmission electron microscope (TEM). According to this, the nanoparticles have a diameter in the range of about 5 nm to about 50 nm, for example, in the range of about 10 nm to about 30 nm. The cobalt oxidation number of the manufactured cobalt oxide nanoparticles was measured to be in the range of about 2.67 to about 2.75, from which the above composition can be derived.

[0051] FIG. 6 is a graph showing the results of X-ray diffraction analysis (XRD) of a catalyst for a chlorine generation reaction according to one embodiment of the present invention.

[0052] Referring to FIG. 6, the crystal structure analysis results of the catalysts for the chlorine generation reaction of Examples 1 to 3 are shown. Example 1 is cobalt oxide nanoparticles having a composition of Co3O4, and Examples 2 and 3 are M-cobalt oxide nanoparticles. Specifically, Example 2 is M-cobalt oxide nanoparticles of Ru(5 at%)-Co3O4, and Example 3 is M-cobalt oxide nanoparticles of Ru(10 at%)-Co3O4. Examples 2 and 3 were measured after the synthesized Ru-Co3O4 nanoparticles were coated on a titanium (Ti) substrate and heat-treated at a temperature of 300°C to 500°C for 1 hour. Therefore, the peak for the titanium (Ti) substrate was indicated.

[0053] As illustrated in Fig. 6, in Example 3 where the molar number of Ru(acac)3 relative to Co3O4 is 10 at%, the peak of RuO2 can be confirmed in the XRD data. From this, it can be confirmed that M-cobalt oxide nanoparticles having a structure in which a transition metal is bonded to cobalt oxide nanoparticles were formed.

[0054] Additionally, the main peak shift in the XRD data of the cobalt oxide nanoparticles confirmed that Ru exists within the cobalt oxide lattice.

[0055] Method for producing a catalyst for chlorine generation reaction

[0056] A method for producing a catalyst for a chlorine generation reaction according to an embodiment of the present invention comprises the steps of: dissolving an antimony (Sb) precursor in a mixed solvent of isopropyl alcohol (IPA) and water to prepare an antimony (Sb) precursor solution; dispersing a tin (Sn) precursor in the antimony (Sb) precursor solution; introducing a solution in which a ruthenium (Ru) precursor is dissolved into the antimony (Sb) and tin (Sn) precursor solutions; and introducing a solution in which nanoparticles containing cobalt oxide are dispersed in isopropyl alcohol (IPA) into the solution in which the antimony (Sb) precursor, the tin (Sn) precursor, and the ruthenium (Ru) precursor are dissolved, thereby preparing a catalyst composition.

[0057] In one embodiment, a method for preparing a catalyst for a chlorine generation reaction is as follows.

[0058] First, a step of preparing an antimony (Sb) precursor solution by dissolving the antimony (Sb) precursor in a mixed solvent of isopropyl alcohol (IPA) and water, and a step of dispersing a tin (Sn) precursor in the antimony (Sb) precursor solution are performed.

[0059] Specifically, when the metal oxide is ATO, 44.7 mg of SbCl3 is dissolved in a solvent (weighed in a 50 mL Falcon tube) containing 38.7 mL of IPA and 7.8 mL of deionized water to prepare an antimony (Sb) precursor solution (after weighing in a weighing dish, use a portion of the solution to completely dissolve SbCl3 and then place it back in the Falcon tube).

[0060] The above antimony (Sb) precursor solution is diluted 10 times with a mixed solvent of IPA and deionized water.

[0061] Add 457.8 mg of SnCl4*5H2O to 15.5 mL of the above diluted antimony (Sb) precursor solution and disperse. The step of dispersing the tin (Sn) precursor is performed only by vortexing. In addition to IPA, ethanol can also be used as the solvent.

[0062] Next, a step is performed in which a solution containing a ruthenium (Ru) precursor is dissolved and added to the antimony (Sb) and tin (Sn) precursor solutions.

[0063] Specifically, in the above step, after quantifying 357.9 mg of Ru(acac) and 24.8 mg of PdCl in a 70 mL vial, the antimony (Sb) and tin (Sn) precursor solution is poured therein.

[0064] Next, a step of preparing a catalyst composition is performed by adding a solution containing nanoparticles containing cobalt oxide dissolved in isopropyl alcohol (IPA) to a solution containing the antimony (Sb) precursor, tin (Sn) precursor, and ruthenium (Ru) precursor.

[0065] Specifically, 1 mL (0.438 mmol) of Co3O4NPs solution is added, and 1 mL of IPA is additionally added. Thus, the solution prepared has a concentration of Co3O425 mM.

[0066] Additionally, a step of ultrasonically treating the catalyst composition may be further included after the step of preparing the catalyst composition.

[0067] The above step involves ultrasonically dispersing the dispersed catalyst composition in a table ultrasonic disperser (sonicator) for 20 minutes.

[0068] Meanwhile, when the metal oxide is NTO, 7.5 ml of titanium butoxide is dispersed in 10 ml of ethanol, and 0.56 ml of niobium ethoxide is added and dispersed therein. 2.5 ml of hydrochloric acid (HCl) (37%) diluted in 5 ml of ethanol is added dropwise to the solution at 50°C and 1500 rpm. 1.2 g of hexadecyl trimethylammonium bromide (CTAB) dispersed in 15 mL of ethanol is added dropwise to the solution, and the mixture is maintained for about 1 hour. 5 mL of water is added and the mixture is further maintained for about 1 hour. Next, the solution is maintained in a water bath at 60°C and 1500 rpm for about 12 hours. 1.2 mL of the gel thus formed is dissolved in 15.3 ml of a solvent containing IPA and deionized water. Next, 1 mL of a cobalt nanoparticle solution dispersed in IPA is added to the above solution. The resulting solution has a concentration of Co3O425 mM.

[0069] The volume ratio of isopropyl alcohol (IPA):water used in the above catalyst manufacturing method may be 4:1 to 20:1.

[0070] The above catalyst composition may further include palladium (Pd) in an amount of 0.1 to 5 at% relative to 100 at% of the metal contained in the catalyst composition.

[0071] The above antimony (Sb) precursor may be antimony trichloride (SbCl3), the above tin (Sn) precursor may be tin tetrachloride pentahydrate (SnCl4*5H2O), and the above ruthenium (Ru) precursor may be ruthenium acetylacetonate (Ru(acac)3), but is not necessarily limited thereto.

[0072] Catalyst structure for chlorine generation reaction

[0073] FIGS. 7A to 7E are schematic cross-sectional views each showing a catalyst structure for a chlorine generation reaction according to one embodiment of the present invention.

[0074] Referring to FIG. 7a, a catalyst structure (100a) for a chlorine generation reaction may include a substrate (110) and a catalyst layer (CL) including nanoparticles (120) including cobalt oxide.

[0075] The substrate (110) may be made of a conductive material, for example, a metal material, a carbon material, or an oxide. The substrate (110) may include, for example, at least one of titanium (Ti), copper (Cu), mercury (Hg), gold (Au), silver (Ag), platinum (Pt), tin (Sn), zinc (Zn), iron (Fe), nickel (Ni), and alloys thereof. Alternatively, the substrate (110) may include, for example, at least one of carbon paper, glassy carbon, fluorine-doped tin oxide (FTO), and indium-doped tin oxide (ITO).

[0076] Among the above-described materials, the titanium (Ti) substrate may be a porous titanium (Ti) substrate, a plate-shaped titanium (Ti) substrate, or a mesh-shaped titanium (Ti) substrate.

[0077] The surface of the porous titanium (Ti) substrate, plate-shaped titanium (Ti) substrate, or mesh-shaped titanium (Ti) substrate may be roughened to improve adhesion with the catalyst layer.

[0078] In order to improve adhesion to the catalyst layer, the surface of the porous titanium (Ti) substrate, plate titanium (Ti) substrate, or mesh titanium (Ti) substrate can be roughened using etching, grit blasting, or a combination thereof.

[0079] In one embodiment of the present invention, the substrate (110) is a porous titanium (Ti) substrate, a plate-shaped titanium (Ti) substrate, or a mesh-shaped titanium (Ti) substrate, and by forming a roughness on the surface of the substrate, the adhesive strength with the catalyst layer (CL) can be further improved.

[0080] The catalyst layer (CL) may be a layer composed of nanoparticles (120). The nanoparticles (120) may be cobalt oxide nanoparticles that have not been treated with a transition metal, or the M-cobalt oxide nanoparticles described above. The catalyst layer (CL) may be manufactured by coating the nanoparticles (120) on a substrate (110) by a method such as brush coating, spraying, spin coating, drop coating, or dip coating, or by manufacturing them in the form of a paste or ink and applying them. The thickness of the catalyst layer (CL) may be, for example, in a range of about 100 nm to about 10 μm.

[0081] Referring to FIG. 7b, a catalyst structure (100b) for a chlorine generation reaction may include a substrate (110), and a catalyst layer (CL) including nanoparticles (120) including cobalt oxide and a metal oxide (130) in which the nanoparticles (120) are dispersed.

[0082] The catalyst layer (CL) of the present embodiment may be a state in which nanoparticles (120) are dispersed or mixed in a metal oxide (130). The metal oxide (130) may include at least one of antimony doped tin oxide (ATO), indium-doped tin oxide (ITO), and niobium doped titanium oxide (NTO). Since the catalyst layer (CL) has a structure in which nanoparticles (120) are mixed in the metal oxide (130), the catalyst layer (CL) can be formed into various 3D structures, and the conductivity of the catalyst structure (100b) can be improved. In addition, the catalyst layer (CL) is characterized by having a porous 3D structure in which nanoparticles (120) are dispersed in the form of particles in the metal oxide (130).

[0083] In this case, for example, the atomic ratio of antimony (Sb):tin (Sn) in ATO may be in the range of about 1:20 to about 1:200, and the atomic ratio of niobium (Nb):titanium (Ti) in NTO may be in the range of about 1:6 to about 1:12. When the metal oxide (130) is ATO, in the catalyst layer (CL), the atomic ratio of cobalt (Co) of the nanoparticles (120) to tin (Sn) of the metal oxide (130) (Co: Sn) may be in the range of 1:1 to 3:1. This will be described in more detail with reference to FIG. 7a below. Since the catalyst layer (CL) has a structure in which nanoparticles (120) are mixed with the metal oxide (130), the catalyst layer (CL) can be formed into various 3D structures, and the conductivity of the catalyst structure (100a) can be improved.

[0084] The thickness of the catalyst layer (CL) may be, for example, in the range of about 100 nm to about 10 μm. Preferably, the thickness of the catalyst layer (CL) may be in the range of about 200 nm to about 5 μm or about 300 nm to about 2 μm, and more preferably in the range of about 100 nm to less than 1 μm.

[0085] According to one embodiment of the present invention, even when the thickness of the catalyst layer (CL) is less than 1 ㎛, 500 mA / cm 2 The electrochemical long-term stability at current density is more than 500 h, and the chlorine generation efficiency is more than 95% under 0.6 M NaCl conditions (Fig. 8), and an excellent effect of more than 80% of the chlorine generation efficiency under 20 mM NaCl conditions can be obtained.

[0086] According to one embodiment of the present invention, when the transition metal particle is ruthenium (Ru) and the metal oxide is antimony doped tin oxide (ATO), the metal oxide is SnO2, ruthenium (Ru) doped SnO in the catalyst layer. x (1≤x≤2) and Co-SnO x (0 <x≤2)(Co:Sn= 1:10~5:1) 금속간 산화물(Intermetallic oxide) 형태 중 어느 하나 이상의 형태를 가질 수 있다(도 9a 내지 도 9d).

[0087] The content of antimony (Sb) contained in the metal oxide may be, for example, 0.1 at% to 5.0 at%. Preferably, the content of antimony (Sb) contained in the metal oxide may be 0.2 at% to 4.0 at% or 0.3 at% to 3.0 at%, more preferably 0.1 at% to 1.0 at%, and more preferably 0.2 at%.

[0088] In the case of existing commercialized ATO (Antimony doped Tin Oxide), the content of antimony (Sb) is 10 at% or more, but in one embodiment of the present invention, the content of antimony (Sb) included in the metal oxide is characterized by being 5.0 at% or less.

[0089] According to one embodiment of the present invention, even if the content of antimony (Sb) included in the metal oxide is added in a small amount of 1.0 at% or less, 500 mA / cm 2 Excellent effects can be obtained, such as electrochemical long-term stability of 500 h or more at current density, chlorine generation efficiency of 95% or more under 0.6 M NaCl conditions, and chlorine generation efficiency of 80% or more under 20 mM NaCl conditions.

[0090] In particular, when the content of antimony (Sb) included in the metal oxide is increased to 3.0 at% or less, an even better effect of chlorine generation efficiency of 95% or more under low-salt (20 mM NaCl) conditions can be obtained in addition to the above effect.

[0091] According to embodiments, the catalyst layer (CL) may further include a binder to prevent cracking of the surface. The binder may include at least one of polyvinyl alcohol (PVA), ethyl cellulose (EC), and hydroxypropyl cellulose (HPC). In exemplary embodiments, the catalyst layer (CL) may have a structure in which layers each including a metal oxide (130) and nanoparticles (120) are alternately laminated.

[0092] According to embodiments, the catalyst layer (CL) may further include a heterogeneous element. The heterogeneous element may be, for example, at least one of aluminum (Al), palladium (Pd), tungsten (W), iridium (Ir), and tantalum (Ta). In the catalyst layer (CL), the heterogeneous element may be contained in a range of about 4 at% to about 18 at% of the total metal elements in the metal oxide (130). By further including the heterogeneous element, the chlorine generation efficiency of the catalyst layer (CL) may be further improved. This will be described in more detail with reference to Table 4 below.

[0093] Referring to FIG. 7c, a catalyst structure (100c) for a chlorine generation reaction may include a substrate (110), an interlayer (140) disposed on the substrate (110) and including a conductive material, and a catalyst layer (CL) including nanoparticles (120) including cobalt oxide.

[0094] The conductive material included in the interlayer (140) may be at least one selected from the group consisting of titanium (Ti) and tin (Sn).

[0095] Unlike the embodiment of FIG. 7a, the catalyst structure (100c) of the present embodiment may further include an intermediate layer (140) interposed between the substrate (110) and the catalyst layer (CL). The intermediate layer (140) may include at least one conductive material selected from the group consisting of titanium (Ti) and tin (Sn), and may further include at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), palladium (Pd), aluminum (Al), tungsten (W), tantalum (Ta), antimony (Sb), and niobium (Nb).

[0096] The above intermediate layer (140) is Ru a Sn b Ti c O d (0 < a ≤ 0.4, 0 ≤ b ≤ 0.7, 0 ≤ c ≤ 0.7, a+b+c=1, d=2) may include a metal oxide having a composition formula. For example, the intermediate layer (140) may be Ru a Sn b Ti c It may include a metal oxide having a composition formula of O2(0 < a ≤ 0.4, 0 < b ≤ 0.7, 0 < c ≤ 0.7, a+b+c=1), for example, Ru a Sn b Ti cIt may include a metal oxide having a composition formula of O2(0 < a ≤0.4, 0 < b < 0.5, 0 < c < 0.5, b=c, a+b+c=1). The intermediate layer (140) may perform a function of reducing the resistance between the substrate (110) and the catalyst layer (CL). The thickness of the intermediate layer (140) may be, for example, in a range of about 100 nm to about 10 μm.

[0097] According to embodiments, the intermediate layer (140) may further include a heterogeneous element. The heterogeneous element may be, for example, at least one of aluminum (Al), palladium (Pd), tungsten (W), iridium (Ir), and tantalum (Ta). In the intermediate layer (140), the heterogeneous element may be contained in a range of about 4 at% to about 18 at% of the total metal elements in the metal oxide. By further including the heterogeneous element in the intermediate layer (140), the chlorine generation efficiency may be improved. This will be described in more detail with reference to Table 2 below.

[0098] The above catalyst layer (CL) may be a layer composed of nanoparticles (120). The nanoparticles (120) may be cobalt oxide particles treated with a transition metal. For example, the nanoparticles (120) may be Co x O 1-x (0.33 < x < 0.50), for example, cobalt oxide particles having a composition of Co3O4. The nanoparticles (120) may further include relatively small-sized transition metal particles present on the surface of the cobalt oxide particles. Accordingly, the composition of the nanoparticles (120) is expressed as M-Co, indicating the transition metal (M) element. x O 1-x(0.33 < x < 0.50). The transition metal particles may include at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), and palladium (Pd). The transition metal particles may have a size of about 0.1 nm to about 3 nm. The nanoparticles (120) may have a diameter in the range of about 10 nm to about 50 nm.

[0099] The catalyst layer (CL) can be manufactured by coating nanoparticles (120) on a substrate (110) by brush-coating, spraying, spin-coating, drop-coating, dip-coating, etc., or by manufacturing them in the form of a paste or ink and applying them. The thickness of the catalyst layer (CL) can be, for example, in the range of about 100 nm to about 10 μm.

[0100] Referring to FIG. 7d, a catalyst structure (100d) for a chlorine generation reaction may include a substrate (110), an intermediate layer (140) disposed on the substrate (110) and including titanium oxide, and a catalyst layer (CL) including nanoparticles (120) including cobalt oxide and a metal oxide (130) on which the nanoparticles (120) are dispersed.

[0101] Unlike the embodiment of FIG. 3b, the catalyst structure (100d) of the present embodiment may further include an intermediate layer (140) interposed between the substrate (110) and the catalyst layer (CL). The description of the intermediate layer (140) may be equally applied to the description given above with reference to FIG. 7c.

[0102] Referring to FIG. 7e, a catalyst structure (100e) for a chlorine generation reaction may include a substrate (110), an interlayer (140) disposed on the substrate (110) and including titanium oxide, a catalyst layer (CL) including nanoparticles (120) including cobalt oxide and a metal oxide (130) in which the nanoparticles (120) are dispersed, and a metal oxide layer (145) disposed between the catalyst layer (CL) and the interlayer (140) and including ruthenium oxide (RuO2).

[0103] The catalyst structure (100e) of the present embodiment may further include a metal oxide layer (145) interposed between the intermediate layer (140) and the catalyst layer (CL), unlike the embodiment of FIG. 7d. The intermediate layer (140) may have the composition described above with reference to FIG. 7c, and the metal oxide layer (145) may include a metal oxide having a different composition from that of the intermediate layer (140). For example, the intermediate layer (140) may be Ru. a Sn b Ti c O d (0 < a ≤ 0.4, 0 ≤ b ≤ 0.7, 0 ≤ c ≤ 0.7, a+b+c=1, d=2), and the metal oxide layer (145) is Ru a Sn b Ti cIt may have a composition formula of O2(0 < a ≤ 1, 0 ≤ b ≤ 0.7, 0 ≤ c ≤ 0.7, a+b+c=1) and may include, for example, RuO2. For example, the intermediate layer (140) may include ruthenium-tin-titanium oxide, and the metal oxide layer (145) may include ruthenium oxide. The metal oxide layer (145) may perform a function of reducing the resistance between the substrate (110) and the catalyst layer (CL) together with the intermediate layer (140). The thickness of the metal oxide layer (145) may be, for example, in a range of about 100 nm to about 10 μm, and may be prepared by coating in the same manner as the intermediate layer (140) described above.

[0104] According to one embodiment of the present invention, the catalyst structure (100e) for the chlorine generation reaction is disposed between the catalyst layer (CL) and the interlayer (140) and includes a metal oxide layer (145) containing ruthenium oxide (RuO2), so that acid stability can be improved by ruthenium (Ru) diffusing into the catalyst layer (CL) and the interlayer (140) by heat treatment during the manufacturing process of the catalyst structure of the present embodiment.

[0105] Specifically, when washing a catalyst structure for a chlorine generation reaction using a conventional acid, there was a problem that the catalyst structure was vulnerable to the acid, but according to one embodiment of the present invention, since ruthenium (Ru) is diffused into the catalyst layer (CL) and the interlayer (140) by heat treatment during the catalyst structure manufacturing process, the stability of the catalyst structure against the acid used in the washing process can be improved.

[0106] In addition, as the ruthenium (Ru) is diffused into the catalyst layer (CL) and the interlayer (140), the low-salt efficiency of the catalyst layer increases, and the stability of the electrode is improved, so that the lifespan can be extended.

[0107] Electrochemical system for chlorine generation reaction

[0108] Figure 10 is a schematic perspective view of an electrochemical system for chlorine generation reaction according to one embodiment of the present invention.

[0109] Referring to FIG. 10, the electrochemical system (200) for chlorine generation reaction may include a reactor (210), an electrolyte solution (220), electrode supports (230), a first electrode (cathode) (240), a second electrode (anode) (250), a catalyst layer (260) on the second electrode (250), and a power supply (270). The first electrode (240) and the second electrode (250) may be connected by the power supply (270). According to embodiments, the electrochemical system (200) for chlorine generation reaction may be a three-electrode system that further includes a reference electrode for measuring the substrate potential of the first electrode (240) and the second electrode (250), rather than a two-electrode system as in FIG. 4. In exemplary embodiments, the electrochemical system (200) for chlorine generation reaction may further include a membrane made of an ion-permeable material, such as Nafion, a cation exchange membrane, etc., dividing the first electrode (240) and the second electrode (250).

[0110] An electrochemical system (200) for chlorine generation reaction may be a system that generates chlorine (Cl2) by oxidizing chlorine ions from sodium chloride (NaCl) or the like in an electrolyte solution (220) at a second electrode (250).

[0111] The reactor (210) may be made of a material capable of accommodating an electrolyte solution (220). The reactor (210) may be made of, for example, Pyrex, acrylic, polyvinyl chloride (PVC), etc.

[0112] An electrolyte solution (220) is contained within the reactor (210) and can serve as a source of chlorine. The electrolyte solution (220) can contain chlorine (Cl), and can be, for example, a solution containing sodium chloride (NaCl), sodium perchlorate (NaClO4), or the like. The concentration of the electrolyte solution (220) can range from about 10 mM to about 4 M, for example.

[0113] The first electrode (240) and the second electrode (250) may be supported by a 'T' shaped electrode support (230) and partially or completely immersed in an electrolyte solution (220). The first electrode (240) may be a counter electrode, and the second electrode (250) may be a working electrode. The first electrode (240) and the second electrode (250) may each be made of a semiconductor material or a conductive material. For example, the first electrode (240) and the second electrode (250) may include at least one of titanium (Ti), copper (Cu), mercury (Hg), gold (Au), silver (Ag), platinum (Pt), tin (Sn), zinc (Zn), iron (Fe), nickel (Ni), and alloys thereof. In particular, the first electrode (240) and the second electrode (250) may include, for example, a titanium mesh. The first electrode (240) may be a reduction electrode, and the second electrode (250) may be an oxidation electrode. The distance between the first electrode (240) and the second electrode (250) may be in the range of about 0.6 mm to about 5 cm.

[0114] A catalyst layer (260) may be coated on the surface of the second electrode (250). The catalyst structure (100) including the second electrode (250) and the catalyst layer (260) may be the catalyst structures (100a, 100b, 100c, 100d, 100e) for chlorine generation reaction of the embodiments described above with reference to FIGS. 7a to 7e. Therefore, the above description may be equally applied to each of the catalyst structures (100a, 100b, 100c, 100d, 100e) for chlorine generation reaction.

[0115] The power supply (270) can cause an oxidation reaction of chlorine to occur by applying an electrical signal to the reactor (210).

[0116] When voltage is applied between the first electrode (240) and the second electrode (250) by the power supply (270) in the electrochemical system (200) for chlorine generation reaction, a reaction occurs in which hydrogen is generated at the first electrode (240) and a chlorine (Cl)-containing substance is generated at the second electrode (250). The reaction at the second electrode (250) is expressed by the following reaction formulas 1 to 3.

[0117] [Reaction Scheme 1] 2 Cl - → Cl2+ 2e -

[0118] [Reaction Formula 2] Cl2+ H2O → HClO + Cl - + H +

[0119] [Reaction Scheme 3] HOCl + H2O → OCl - + H3O +

[0120] The chlorine evolution reaction is a two-electron participation reaction, and the thermodynamic potential is 1.36 V vs. SHE. As shown in the above reaction equations, chlorine (Cl2) produced by the chlorine evolution reaction is converted into active chlorine, hypochlorous acid (HClO) or hypochlorite (ClO - ) can be converted to.

[0121] Catalytic properties according to the intermediate layer in the catalyst structure for chlorine generation reaction

[0122] Hereinafter, with reference to FIGS. 11 to 14d, the mechanical properties and catalytic properties analysis results according to the composition and structure of the intermediate layer in the above-described catalyst structure for chlorine generation reaction are described.

[0123] Figure 11 is an electron microscope photograph showing the results of surface analysis of intermediate layers according to one embodiment of the present invention.

[0124] Referring to Figure 11, the results of analyzing the surfaces of intermediate layers with different compositions using a scanning electron microscope (SEM) are shown. The intermediate layers used in the analysis are Ru:Sn:Ti with a ratio of 30:0:70, 30:70:0, and 30:35:35, respectively. 0.3 Ti 0.7 O2, Ru 0.3 Sn 0.7 O2, and Ru 0.3 Sn 0.35 Ti 0.35 It has a composition of O2. For each intermediate layer, the two left columns represent the surface on the plane of the titanium (Ti) mesh forming the electrode, and the right column represents the surface on the inclined plane of the titanium (Ti) mesh.

[0125] As shown in Fig. 11, the intermediate layers may have a shape composed of nanoparticles of several to several hundred nanometers, and the specific surface morphology may be changed depending on the composition of the intermediate layers. In particular, it is analyzed that the surface has high stability without cracks in the embodiment in which the composition of Sn and Ti is the same, that is, Ru:Sn:Ti = 30:35:35. Accordingly, the composition of the intermediate layer is particularly Ru. a Sn b Ti c O d(0 < a ≤ 0.4, 0 ≤ b ≤ 0.7, 0 ≤ c ≤ 0.7, a+b+c=1, d=2) can be.

[0126] FIG. 12 is a photograph showing the results of mechanical stability analysis of intermediate layers in catalyst structures according to one embodiment of the present invention.

[0127] Referring to FIG. 12, in a catalyst structure having a structure such as FIG. 7d, the mechanical stability was analyzed by changing the composition of the intermediate layer (140) and performing a taping test for the case where the catalyst layer (CL) includes ATO as a metal oxide (130) and Ru-Co3O4 as nanoparticles (120). In the catalyst layer (CL), the atomic ratio of cobalt (Co) of Ru-Co3O4 to tin (Sn) of ATO was 1:1, and unless otherwise stated in the following analyses, it can be seen that the analyses were performed under the conditions that the atomic ratio of cobalt (Co) to tin (Sn) was 1:1 and the content ratio of Co3O4 to ATO was 1:3.

[0128] As shown in Fig. 12, the intermediate layers are Ru oxide (Ru 0.3 Ti 0.7 O2), Ru-Ir oxide (Ru 0.15 Ir 0.15 Ti 0.7 O2), Ru-Pd oxide (Ru 0.15 Pd 0.15 Ti 0.7 O2), Ru-Sn oxide (Ru 0.3 Sn 0.7 O2), Ru-Sn-Ti oxide (Ru 0.3 Sn 0.35 Ti 0.35O2) was performed. The taping test was performed by attaching and removing tape on the catalyst structure to measure the mechanical stability. The intermediate layers that were least likely to be detached by taping were Ru-Sn oxide and Ru-Sn-Ti oxide. From this, it can be seen that the mechanical stability is improved when the intermediate layers include ruthenium (Ru) and tin (Sn).

[0129] FIGS. 13a and 13b are graphs showing the results of catalyst stability evaluations for catalyst structures according to one embodiment of the present invention.

[0130] In Fig. 13a, the results of the catalyst stability evaluation for the first to fourth embodiments (A, B, C, D) of the catalyst structure having the structure as in Fig. 7d are shown. In the first to fourth embodiments (A, B, C, D), the catalyst layer (CL) commonly includes ATO as a metal oxide (130) and further includes 0.9 at % of a palladium (Pd) heteroatom based on the total metal atoms, and the nanoparticles (120) include Ru-Co3O4. In the catalyst layer (CL), the atomic ratio of cobalt (Co) of Ru-Co3O4 to tin (Sn) of ATO was 1:1. In the first to fourth embodiments (A, B, C, D), the composition of the intermediate layer (140) was Ru, respectively. 0.3 Ti 0.7 O2, Ru 0.15 Ir 0.15 Ti 0.7 O2, Ru 0.3 Sn 0.35 Ti 0.35 O2, and Ru 0.3 Ti 0.7 It's O2.

[0131] The catalyst stability in the chlorine generation reaction was measured using a constant current method in a two-electrode system as shown in Fig. 4. The first electrode (240) and the second electrode (250) used titanium (Ti) mesh, the second electrode (250) used a titanium (Ti) substrate, and 1 L of 600 mM NaCl was used as the electrolyte solution (220). The area of ​​the first electrode (240) was 25 cm 2 And, The area of ​​the second electrode (250) is 1 cm 2 , and the current density is 500 mA / cm 2 The time for the potential to reach 16 V under these conditions was analyzed. In the following, unless otherwise stated, it can be understood that the above conditions are equally applied in the catalyst stability evaluation.

[0132] Stability evaluation results: 500 mA / cm 2The time required for the voltage to reach 16 V at the current density was the longest in the second embodiment (B) at about 480 hours, followed by the third embodiment (C) at about 320 hours. The chlorine generation efficiency was about 87.9% in the first embodiment (A), about 84.1% in the second embodiment (B), about 81.8% in the third embodiment (C), and about 77.3% in the fourth embodiment (D). The chlorine generation efficiency means the ratio of the amount of charge (e.g., the number of electrons) participating in the chlorine generation reaction to the amount of charge consumed (e.g., the number of electrons). The chlorine generation efficiency was measured as follows. Using 20 mM NaCl, the amount of charge participating in the chlorine generation reaction was calculated by multiplying the current value (200 mA) that flowed for a certain period of time (e.g., 60 seconds), and the amount of chlorine generated in the oxidation reaction was measured by the DPD (N,N-diethyl-p-phenylenediamine) colorimetry method, and the ratio of the amount of charge participating in the chlorine generation reaction was calculated and expressed as the Faradaic efficiency or current efficiency. According to this, in the case of the second embodiment (B), excellent catalytic properties were shown in terms of both stability and efficiency, but since it included iridium (Ir), its price competitiveness was somewhat low. In the case of the third embodiment (C), excellent results were shown in terms of stability and efficiency even though iridium (Ir) was not included. In addition, considering that the intermediate layer made of Ru-Sn-Ti oxide showed mechanically stable results as described above with reference to FIG. 4, an intermediate layer having the composition of the third embodiment (C) and a similar composition may be employed in a catalyst structure.

[0133] According to one embodiment of the present invention, the electrolyte is 20 mM sodium chloride (NaCl), and the faradaic efficiency of the chlorine generation reaction in the catalyst structure satisfies a range of 80% or more. For example, it can be interpreted as being in the range of about 75% to about 95%.

[0134] Figure 13b illustrates the results of catalyst stability evaluations for first and second embodiments (A, B) of a catalyst structure having the same structure as Figure 7d. Hereinafter, expressions such as "first embodiment" and "second embodiment" may be understood as terms used only within the description of the corresponding drawings. Accordingly, the first and second embodiments (A, B) of Figure 7b may correspond to separate embodiments from the embodiments of Figure 7a.

[0135] In the first and second embodiments (A, B), the catalyst layer (CL) commonly includes ATO as a metal oxide (130) and the nanoparticles (120) include Ru-Co3O4. In the catalyst layer (CL), the atomic ratio of cobalt (Co) of Ru-Co3O4 to tin (Sn) of ATO was 3:1. In the first and second embodiments (A, B), the composition of the intermediate layer (140) was Ru 0.3 Ti 0.7 O2 and Ru 0.3 Sn 0.7 It's O2.

[0136] Stability evaluation results: 500 mA / cm 2 The time required for the voltage to reach 10 V at a current density was longer for the second embodiment (B) at approximately 920 hours or more, followed by the first embodiment (A) at approximately 660 hours or more. Therefore, it can be seen that the case where the intermediate layer includes tin (Sn) in addition to ruthenium (Ru) is advantageous in terms of stability compared to the case where the intermediate layer includes titanium (Ti) in addition to ruthenium (Ru).

[0137] Figures 14a to 14d are graphs showing the results of catalyst stability evaluation for catalyst structures according to one embodiment of the present invention.

[0138] Figure 14a shows the results of evaluating the catalyst stability for a first embodiment (A) of a catalyst structure for a chlorine generation reaction having a structure like Figure 7d and a second embodiment (B) of a catalyst structure for a chlorine generation reaction having a structure like Figure 7e. In the first and second embodiments (A, B), the catalyst layer (CL) commonly includes ATO as a metal oxide (130) and further includes 0.9 at % of a palladium (Pd) heteroatom based on the total metal atoms, and the nanoparticles (120) include Ru-Co3O4. In the first and second embodiments (A, B), the intermediate layer (140) is Ru 0.3 Sn 0.35 Ti 0.35 It is made of O2, and in the second embodiment (B), the metal oxide layer (145) is made of RuO2.

[0139] Stability evaluation results: 500 mA / cm 2 The time required for the voltage to reach 10 V at the current density was longer in the second embodiment (B) at about 900 hours, while it was about 680 hours in the first embodiment (A). That is, the second embodiment (B) showed stability of more than 850 hours. In the case of the second embodiment (B), the chlorine generation efficiency was analyzed to be about 88.6%, while in the case of the first embodiment (A), it was about 81.8%. Accordingly, the second embodiment (B) showed excellent catalytic properties in terms of both stability and chlorine generation efficiency. This is because ruthenium (Ru) is diffused into the intermediate layer (140) and the catalyst layer (CL) by the metal oxide layer (145), and ruthenium (Ru) is contained in a stable form in the catalyst layer (CL), thereby contributing to the improvement of conductivity and increasing the lifespan and acid stability of the electrode structure.

[0140] Figure 14b shows the results of the catalyst stability evaluation for a comparative example (black) having a general intermediate layer composition and an example (red) of a catalyst structure for a chlorine generation reaction having a structure similar to that of Figure 7d.

[0141] Stability evaluation results: 500 mA / cm 2 The time required for the voltage to reach 10 V at a current density was longer for the embodiment at about 2947 hours, while it was about 750 hours for the comparative example. In other words, the embodiment showed stability of about 2200 hours or more.

[0142] Figures 14c and 14d show the results of a catalyst stability evaluation for an example of a catalyst structure for a chlorine generation reaction having a structure similar to that of Figure 7e.

[0143] Stability evaluation results: 500 mA / cm 2 The times required for the voltage to reach 10 V at the current density were approximately 1432 hours and 1309 hours, respectively, indicating excellent stability.

[0144] Additionally, as a result of the acid safety evaluation using a hydrochloric acid (HCl) solution of 5 wt% or less, the structure for the chlorine generation reaction of the second embodiment (B) did not dissolve for more than 300 hours and there was no change in color (Fig. 15).

[0145] Catalytic characteristics according to catalyst layer in catalyst structure for chlorine generation reaction

[0146] Hereinafter, with reference to FIGS. 16a to 16b and FIG. 17, the mechanical properties and catalytic property analysis results according to the composition of the catalyst layer in the above-described catalyst structure for chlorine generation reaction are described.

[0147] FIGS. 16a and 16b are photographs showing the results of mechanical stability analysis of catalyst layers in catalyst structures according to one embodiment of the present invention.

[0148] Referring to Fig. 16a, in the catalyst layer (CL) of the catalyst structure having the same structure as Fig. 7d, the mechanical stability was analyzed for cases where the atomic ratio of cobalt (Co) of nanoparticles (120) Ru-Co3O4 to tin (Sn) of metal oxide (130) ATO was 12:0, 9:1, 3:2, and 1:1. In the examples, the intermediate layer (140) was all Ru 0.3 Sn 0.35 Ti 0.35 O2, and the metal oxide (130) further contained 0.9 at % of a palladium (Pd) heteroelement.

[0149] As shown in Fig. 16a, the mechanical stability is improved in the order of Co:Sn of 12:0, 9:1, 3:1, and 1:1. That is, relatively, as the amount of metal oxide (130) increases relative to the amount of nanoparticles (120) of the catalyst layer (CL), the mechanical stability can be improved. Therefore, considering the mechanical stability, the atomic ratio of Co:Sn in the catalyst layer (CL) can be selected in the range of about 1:1 to about 3:1.

[0150] Referring to Fig. 16b, in a catalyst layer (CL) having a structure similar to Fig. 7d, the mechanical stability was analyzed for cases where the composition of the metal oxide (130) was 100% ATO, 50% ATO and 50% NTO, 25% ATO and 75% NTO, 12.5% ​​ATO and 87.5% NTO, and 100% NTO. The ratio of ATO and NTO refers to the atomic ratio of the metal atoms of ATO and NTO, i.e., (Sn+Sb) / (Sn+Sb)+(Ti+Nb) to (Ti+Nb) / (Sn+Sb)+(Ti+Nb). The metal oxide (130) further contained 0.5 at% of a palladium (Pd) heterogeneous element, and other conditions in the catalyst structure are the same as in Fig. 16a.

[0151] As shown in Fig. 16b, it can be seen that when a portion of NTO is replaced with ATO, mechanical stability is improved. Therefore, the metal oxide (130) in the catalyst layer (CL) may be composed of, for example, ATO, or may be selected from a range in which NTO is mixed with ATO at 87.5% or less.

[0152] Figure 17 is a graph showing the results of catalyst stability evaluation for catalyst structures according to one embodiment of the present invention.

[0153] Referring to FIG. 17, in the catalyst layer (CL) of the catalyst structure having the same structure as FIG. 7d, the nanoparticles (120) include Ru-Co3O4 and the intermediate layer (140) includes Ru. 0.3 Sn 0.35 Ti 0.35 Catalyst stability evaluation was performed on the first to fourth examples (A, B, C, D) which consist of O2 and have different compositions of metal oxide (130). In the first to fourth examples (A, B, C, D), the metal oxide (130) further included 0.5 at % of a palladium (Pd) heterogeneous element. The first to fourth examples (A, B, C, D) are cases where ATO is 100 %, ATO is 50 %, NTO is 50 %, NTO is 100 %, and titanium oxide (TiO2) is 100 %, respectively. Here, NTO is Nb 0.1 Ti 0.9 It has a composition of O2. In this stability evaluation, 0.6 M NaCl was used as the electrolyte solution (220), and 1000 mA / cm was used for the second electrode (250). 2 A current density of was applied.

[0154] As shown in Fig. 17, the stability evaluation results are 1000 mA / cm 2The time required for the voltage to reach 16 V at a current density was the longest in Example 2 (B), at approximately 180 hours, followed by Example 3 (C) and Example 1 (A). Example 4 (D) was shorter, at less than 40 hours. This indicates that the stability of the catalyst layer can be further improved when it includes NTO. In particular, Example 2 (B), which includes 50% ATO and 50% NTO, exhibits excellent catalyst stability.

[0155] Table 1 below shows the chlorine generation efficiency according to the composition of the metal oxide (130). Examples 1 to 3 in Table 1 are the same as Examples 1 to 3 in FIG. 17, respectively. The chlorine generation efficiency increased in the order of Example 1, Example 2, and Example 3. Therefore, when combined with the results described above with reference to FIGS. 16b and 17, it can be seen that when the catalyst layer includes NTO, particularly in the case of Example 2 (B) including 50% ATO and 50% NTO, mechanical stability and chlorine generation efficiency are secured, while the catalyst stability is excellent.

[0156] Atomic chlorine generation efficiency of metal elements in the catalyst structure catalyst layer 300 rpm First embodiment Co: 49.75 %, Pd: 0.49 %, Sn: 49.50 %, Sb: 0.25 % 86.74 % ± 1.74 % Second embodiment Co: 49.75 %, Pd: 0.49 %, Sn: 24.75 %, Sb: 0.12 %, Ti: 22.39 %, Nb: 2.49 % ) 90.90 % ± 1.97 % Third embodiment Co: 49.75 %, Pd: 0.49 %, Ti: 44.78 %, Nb: 4.97 % 91.28 % ± 1.74 %

[0157] Catalytic characteristics according to the introduction of heterogeneous elements in the catalyst structure for chlorine generation reaction

[0158] Below, the results of the analysis of catalyst characteristics according to the introduction of heterogeneous elements in the intermediate layer and the catalyst layer in the above-described catalyst structure for the chlorine generation reaction are described.

[0159] Table 2 below shows the chlorine generation efficiency according to the introduction of heterogeneous elements in the intermediate layer. In the catalyst structure of Fig. 7d, the intermediate layer (140) is Ru. 0.3 Sn 0.35 Ti 0.35 The chlorine generation efficiency was analyzed for cases where aluminum (Al) was added as a heterogeneous element at 1 at%, 5 at%, 10 at%, and 20 at% relative to the entire intermediate layer (140) composition while being composed of O2. The catalyst layer (CL) includes ATO as a metal oxide (130) and the nanoparticles (120) include Ru-Co3O4.

[0160] As shown in Table 2 below, as the content of the heterogeneous element, aluminum (Al), increased, the chlorine generation efficiency also increased. When 5 at% of aluminum (Al) was added and 4.9 at% of the metal elements were contained in the intermediate layer, the chlorine generation efficiency was approximately 75%. When 10 at% and 20 at% of aluminum (Al) were added and 9.2 at% and 16.6 at% of the metal elements were contained in the intermediate layer, respectively, the chlorine generation efficiency was greater than 80%. From this, it can be seen that excellent chlorine generation efficiency is exhibited when the heterogeneous element in the intermediate layer is contained in the range of about 4 at% to about 18 at% of the metal elements.

[0161] In the case of the potentials in Table 2, the lower the potential, the less power is required to generate the same amount of chlorine, so it can be interpreted that the catalytic activity is high.

[0162] Intermediate layer compositionAtomic potential of metal elements in the intermediate layer (V)Chlorine generation efficiency (%)Ru 0.3 Sn 0.35 Ti 0.35O2Ru: 30.0 at%, Sn: 35.0 at%, Ti: 35.0 at%6.85 - 6.9462.5Ru 0.3 Sn 0.35 Ti 0.35 O2+ Al 1 at %Ru: 29.7 at%, Sn: 34.7 at%, Ti: 34.7 at%, Al: 0.9 at%6.86 - 6.9467.0Ru 0.3 Sn 0.35 Ti 0.35 O2+ Al 5 at %Ru: 28.5 at%, Sn: 33.3 at%, Ti: 33.3 at%, Al: 4.9 at%6.96 - 7.0475.0Ru 0.3 Sn 0.35 Ti 0.35 O2+ Al 10 at %Ru: 27.2 at%, Sn: 31.8 at%, Ti: 31.8 at%, Al: 9.2 at%6.96 - 7.0381.8Ru 0.3 Sn 0.35 Ti 0.35 O2+ Al 20 at %Ru: 25.0 at%, Sn: 29.2 at%, Ti: 29.2 at%, Al: 16.6 at%7.05 - 7.1386.4

[0163] Table 3 below shows the chlorine generation efficiency according to the introduction of heterogeneous elements in the intermediate layer and catalyst layer and the addition of palladium (Pd) to the catalyst layer. In the catalyst structure of Fig. 7d, the intermediate layer (140) is Ru 0.3 Sn 0.35 Ti 0.35The chlorine generation efficiency was analyzed for the cases where aluminum (Al) was added as a heterogeneous element in an amount of 20 at% relative to the entire intermediate layer (140) composition when composed of O2, and when it was not added, and for the case where the catalyst layer (CL) was composed of Ru-Co3O4-ATO, and aluminum (Al) was added as a heterogeneous element in an amount of 20 at% relative to the entire catalyst layer (CL) composition, and palladium (Pd) was added or not added in an amount of 1 at%. As shown in Table 3 below, when palladium (Pd) was added together with aluminum (Al), a heterogeneous element, to the catalyst layer (CL), the chlorine generation efficiency increased. In particular, when palladium (Pd) was added together with aluminum (Al), a heterogeneous element, to the catalyst layer (CL), the chlorine generation efficiency increased significantly under low-salt (20 mM NaCl) conditions.

[0164] Intermediate layer / catalyst layer composition Atomic specific potential (V) of metal elements in the catalyst layer Low salt efficiency (%)Ru 0.3 Sn 0.35 Ti 0.35 O2 / Ru-Co3O4-ATO-Al 20 at %Co: 39.2 at%, Ru: 4.4 at%, Sn: 39.2 at%, Sb: 0.1 at%, Al: 16.7 at%6.48 - 6.5588.6Ru 0.3 Sn 0.35 Ti 0.35 O2+ Al 20 at % / Ru-Co3O4-ATO-Al 20 at %Co: 39.2 at%, Ru: 4.4 at%, Sn: 39.2 at%, Sb: 0.1 at%, Al: 16.7 at%6.54 - 6.6084.1Ru 0.3 Sn 0.35 Ti 0.35 O2+ Al 20 at % / Ru-Co3O4-ATO-Al 20 at %, Pd 1 at%Co: 38.9 at%, Ru: 4.36 at%, Sn: 38.9 at%, Sb: 0.1 at%, Al: 16.6 at%, Pd: 0.9 at%6.72 - 6.8095.5Ru 0.3 Sn 0.35 Ti 0.35O2 / Ru-Co3O4-ATO-Al 20 at%, Pd 1 at%Co: 38.9 at%, Ru: 4.36 at%, Sn: 38.9 at%, Sb: 0.1 at%, Al: 16.6 at%, Pd: 0.9 at%6.88 - 6.9596.6±1.1

[0165] Table 4 below shows the chlorine generation efficiency according to the introduction of heterogeneous elements in the catalyst layer. In the catalyst structure of Fig. 7d, the intermediate layer (140) is Ru. 0.3 Sn 0.35 Ti 0.35 The chlorine generation efficiency was analyzed for cases where the catalyst layer (CL) is composed of O2, the catalyst layer (CL) includes ATO as a metal oxide (130), and the nanoparticles (120) include Ru-Co3O4, and aluminum (Al) as a heterogeneous element is added in amounts of 1 at%, 5 at%, and 20 at% relative to the metal atoms of the entire catalyst layer (CL). As shown in Table 4 below, as the aluminum (Al) content increases, the chlorine generation efficiency also increases. When 5 at% of aluminum (Al) was added and 4.7 at% of the metal elements in the catalyst layer were contained, the chlorine generation efficiency was approximately 84.1%. When 20 at% of aluminum (Al) was added and 16.7 at% of the metal elements were contained in the catalyst layer, the chlorine generation efficiency was greater than 88%. From this, it can be seen that excellent chlorine generation efficiency is exhibited when the heterogeneous element in the catalyst layer is contained in the range of about 4 at% to about 18 at% of the metal elements.

[0166] Composition of intermediate layer and catalyst layerAtomic potential (V) of metal elements in the catalyst layerChlorine generation efficiency (%)Ru 0.3 Sn 0.35 Ti 0.35 O2 / Ru-Co3O4-ATOCo: 47.2 at%, Ru: 5.4 at%, Sn: 47.2 at%, Sb: 0.2 at%6.40 - 6.4780.7Ru 0.3 Sn 0.35 Ti 0.35O2 / Ru-Co3O4-ATO + Al 1 at %Co: 46.9 at%, Ru: 5.3 at%, Sn: 46.7 at%, Sb: 0.2 at%, Al: 0.9 at%6.27 - 6.3583.0Ru 0.3 Sn 0.35 Ti 0.35 O2 / Ru-Co3O4-ATO + Al 5 at %Co: 45.0 at%, Ru: 5.1 at%, Sn: 45.0 at%, Sb: 0.2 at%, Al: 4.7 at%6.50 - 6.5884.1Ru 0.3 Sn 0.35 Ti 0.35 O2 / Ru-Co3O4-ATO + Al 20 at %Co: 39.2 at%, Ru: 4.4 at%, Sn: 39.2 at%, Sb: 0.1 at%, Al: 16.7 at%6.48 - 6.5588.6

[0167] Catalytic properties according to manufacturing method in catalyst structures for chlorine generation reactions

[0168] Hereinafter, with reference to FIGS. 18 to 20b, the results of the catalyst characteristic analysis according to the manufacturing method in the catalyst structure for the above-described chlorine generation reaction are described.

[0169] Figure 18 is an electron microscope photograph showing the results of surface analysis of intermediate layers according to one embodiment of the present invention.

[0170] Referring to Fig. 18, the results of analyzing the surfaces of intermediate layers coated with different solutions using a scanning electron microscope (SEM) are shown. The solutions are solutions that dissolve intermediate layer precursor materials, such as SnCl3, RuCl3, and TiCl3, and contain IPA and H2O. In Fig. 18, the Ru surface when the volume ratio of IPA / H2O is 92.5:7.5, 85:15, 50:50, and 15:85 is shown. 0.3 Sn 0.35 Ti 0.35The results of analyzing the surface of the intermediate layer with O2 composition are shown. The surface is shown before and after coating the solution on a titanium (Ti) substrate and heat-treating at a temperature of 500°C for more than 1 hour.

[0171] When the volume ratio of IPA / H2O is 85:15, the intermediate layer can have a shape composed of nanoparticles measuring several to several hundred nanometers, and is analyzed to have a highly stable surface without cracks. Furthermore, in this case, a stable surface was observed even after heat treatment.

[0172] In addition, when the volume ratio of IPA / H2O was 85:15, the low-salt efficiency was evaluated at 84.4%, which was similar to the existing conditions.

[0173] FIG. 19 is a photograph showing the results of mechanical stability analysis according to heat treatment conditions in catalyst structures according to one embodiment of the present invention.

[0174] Referring to Fig. 19, in the catalyst structure, the catalyst layer (CL) includes ATO as a metal oxide (130) and Ru-Co3O4 as nanoparticles (120). The mechanical stability was analyzed through a taping test while changing the heat treatment conditions after forming the catalyst layer (CL). In the catalyst layer (CL), the atomic ratio of Co3O4 of Ru-Co3O4 to SnO2 of ATO was 1:3, and the ratio of Co:Sn was 1:1. In the catalyst structure, the intermediate layer (140) was Ru 0.3 Sn 0.35 Ti 0.35 It is made of O2.

[0175] The heat treatment conditions were performed at 400 ℃, 450 ℃, and 500 ℃, and the heating rate was 2.8 ℃ / min or 10 ℃ / min. In Fig. 17, the mechanical stability was shown to improve from right to left. Accordingly, the heat treatment temperature was 450 ℃ or higher, especially 500 ℃, and when the heating rate was 5 ℃ / min or lower, especially 2.8 ℃ / min, a catalyst layer with excellent mechanical stability was formed.

[0176] Table 5 below shows the chlorine generation efficiency according to the heat treatment conditions in the catalyst structure. The conditions of the catalyst structure were the same as in Fig. 19, and the chlorine generation efficiency according to the heat treatment temperature and heating rate was analyzed. The electrode area used in the analysis was 5 cm 2 As shown in the table below, when the heat treatment temperature was 450 ℃ or higher, especially 500 ℃, and the heating rate was 5 ℃ / min or lower, especially 2.8 ℃ / min, the chlorine generation efficiency was the highest at 85% or higher, about 89.8%.

[0177] Heat treatment conditions Atomic chlorine generation efficiency (%) of metal elements in the catalyst layer 500 ℃, 2.8 ℃ / min Co: 46.9 at%, Ru: 5.3 at%, Sn: 46.7 at%, Sb: 0.2 at%, Pd: 0.9 at% 89.8450 ℃, 2.8 ℃ / min Co: 46.9 at%, Ru: 5.3 at%, Sn: 46.7 at%, Sb: 0.2 at%, Pd: 0.9 at% 84.1400 ℃, 2.8 ℃ / min Co: 46.9 at%, Ru: 5.3 at%, Sn: 46.7 at%, Sb: 0.2 at%, Pd: 0.9 at% 77.3500 ℃, 10 ℃ / min Co: 46.9 at%, Ru: 5.3 at%, Sn: 46.7 at%, Sb: 0.2 at%, Pd: 0.9 at%84.1

[0178] FIGS. 20A and 20B are graphs showing the results of evaluating the catalytic activity according to the heat treatment conditions of the catalyst layer in catalyst structures according to one embodiment of the present invention. In FIGS. 20A and 20B, current-voltage graphs for examples having the structure of the catalyst structures of FIG. 7D are shown compared to a normal hydrogen electrode (NHE). In the examples, the substrate (110) is a titanium (Ti) mesh, the catalyst layer (CL) includes ATO as a metal oxide (130), and Ru-Co3O4 as nanoparticles (120), and the evaluation was performed at different heat treatment temperatures of 450°C and 500°C. In the catalyst structure, the intermediate layer (140) is Ru 0.3 Sn 0.35 Ti 0.35 It was O2.

[0179] The catalytic activity was measured in a three-electrode system, using 600 mM sodium chloride (NaCl) electrolyte in Fig. 20a and 17 mM NaCl electrolyte in Fig. 20b, by cyclic voltammetry. A titanium (Ti) mesh was used as the counter electrode, a titanium (Ti) mesh was used as the working electrode, and silver / silver chloride (Ag / AgCl) was used as the reference electrode.

[0180] Referring to Fig. 20a, 500 mA / cm 2 The overvoltage in was measured to be about 600 mV for the example heat-treated at 450 ℃ and about 680 mV for the example heat-treated at 500 ℃. Referring to Fig. 20b, 50 mA / cm 2The overvoltage was measured to be about 620 mV for the example heat-treated at 450 ℃ and about 710 mV for the example heat-treated at 500 ℃. The overvoltage can be calculated by adding 0.0591*7 (pH of NaCl) to the voltage value from the graph, calculating the RHE (Real Hydrogen Electrode) value from the NHE (Normal Hydrogen Electrode) value, and subtracting 1.36 V from it. 1.36 V is the thermodynamic potential of the chlorine generation reaction. Since it can be judged that the catalytic properties are better as the overvoltage is smaller, it can be interpreted that the example heat-treated at 450 ℃ has relatively better catalytic activity properties.

[0181] FIGS. 21a to 21c are cross-sectional electron microscope photographs showing the thicknesses of a catalyst layer and an intermediate layer in a catalyst structure for a chlorine generation reaction according to one embodiment of the present invention.

[0182] Figures 21a to 21c provide cross-sectional electron micrographs showing the thicknesses of the catalyst layer and the intermediate layer for examples having the structure of the catalyst structures for the chlorine generation reaction of Figure 7d. In the example illustrated in Figure 21a, the catalyst layer was measured to be 700 nm thick and the intermediate layer to be 700 nm thick. Meanwhile, in the example illustrated in Figure 21b, the catalyst layer was measured to be 1100 nm thick and the intermediate layer to be 1500 nm thick.

[0183] Additionally, in the embodiment illustrated in Fig. 21c, the sum of the thicknesses of the catalyst layer and the intermediate layer was measured to be 886 nm. That is, it can be seen that the sum of the thicknesses of the catalyst layer and the intermediate layer can be less than 1 μm.

[0184] According to one embodiment of the present invention, even when the thickness of the catalyst layer (CL) is less than 1 ㎛, 500 mA / cm 2Excellent effects can be obtained, such as electrochemical long-term stability of 500 h or more at current density, chlorine generation efficiency of 95% or more under 0.6 M NaCl conditions, and chlorine generation efficiency of 80% or more under 20 mM NaCl conditions.

[0185] In addition, according to one embodiment of the present invention, even when the sum of the thicknesses of the catalyst layer and the intermediate layer is less than 1 ㎛, 500 mA / cm 2 Excellent effects can be obtained, such as electrochemical long-term stability of 500 h or more at current density, chlorine generation efficiency of 95% or more under 0.6 M NaCl conditions, and chlorine generation efficiency of 80% or more under 20 mM NaCl conditions.

[0186] Figures 22a to 22c are scanning electron microscope (SEM) photographs showing differences in the morphology of a catalyst layer according to heat treatment conditions in a catalyst structure for a chlorine generation reaction according to one embodiment of the present invention.

[0187] In FIG. 22a and FIG. 22b, scanning electron microscope (SEM) analysis photographs are shown showing the ruthenium (Ru) content and morphological differences of the catalyst layer according to the heat treatment conditions for examples having the structure of the catalyst structures for the chlorine generation reaction of FIG. 7d. In the examples, the substrate (110) is a titanium (Ti) mesh, the catalyst layer (CL) includes ATO as the metal oxide (130), and Ru-Co3O4 as the nanoparticles (120), and the evaluation was performed at different heat treatment temperatures of 450°C and 500°C. In the structure for the chlorine generation reaction, the intermediate layer (140) is Ru 0.3 Sn 0.35 Ti 0.35 It was O2.

[0188] Referring to Fig. 22a, the Ru / Co ratio was measured to be approximately 0.064 for the example heat-treated at 450°C, and referring to Fig. 22b, the Ru / Co ratio was measured to be approximately 0.095 for the example heat-treated at 500°C. Through these results, it can be seen that the Ru content in the catalyst layer (CL) for the example heat-treated at 500°C is 1.5 times higher than that for the example heat-treated at 450°C, and it can be seen that under the heat treatment condition of 500°C, more Ru present in the intermediate layer (140) diffused into the catalyst layer.

[0189] As the above ruthenium (Ru) is diffused into the catalyst layer (CL) and the interlayer (140), the low-salt efficiency of the catalyst layer increases, and the stability of the electrode is improved, so that the lifespan can be extended.

[0190] According to one embodiment of the present invention, lifespan deterioration can be prevented as Ru existing in the intermediate layer (140) diffuses more into the catalyst layer, and therefore, in the case of the example heat-treated at 500°C, the lifespan deterioration prevention effect is relatively better, and thus, it can be interpreted that the electrode stability is better.

[0191] Referring to FIG. 22c, it can be seen that the shape of the catalyst layer in the catalyst structure for a chlorine generation reaction according to one embodiment of the present invention does not have cracks, has a particle-like shape, and has a mat-shaped surface.

[0192] The present invention is not limited to the above-described embodiments and the attached drawings, but is intended to be defined by the appended claims. Therefore, those skilled in the art will appreciate that various substitutions, modifications, and alterations may be made without departing from the technical spirit of the present invention as defined in the claims, and such modifications are also within the scope of the present invention.

Claims

1. Co x O 1-x Nanoparticles comprising cobalt oxide having a composition formula of (0.33 < x < 0.50); ​​and A catalyst for a chlorine generation reaction comprising transition metal particles comprising at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), and palladium (Pd) present on the surface of the nanoparticles.

2. In paragraph 1, The above nanoparticles are catalysts for chlorine generation reactions having a diameter ranging from 5 nm to 50 nm.

3. A catalyst structure for a chlorine generation reaction comprising a catalyst layer comprising a metal oxide, nanoparticles comprising cobalt oxide dispersed in the metal oxide, and transition metal particles comprising at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), and palladium (Pd).

4. In paragraph 3, Nanoparticles containing the above cobalt oxide are Co x O 1-x A catalyst structure for a chlorine generation reaction, wherein the catalyst structure comprises a transition metal particle having a composition formula of (0.33 < x < 0.50) and including at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), and palladium (Pd), and is present on the surface of a nanoparticle containing cobalt oxide.

5. In paragraph 3, The above nanoparticles are catalyst structures for chlorine generation reactions having a diameter ranging from 5 nm to 50 nm.

6. In paragraph 3, The metal oxide is a catalyst structure for a chlorine generation reaction comprising at least one of ATO (Antimony doped Tin Oxide), ITO (Indium-doped Tin Oxide), and NTO (Niobium doped Titanium Oxide).

7. In paragraph 6, When the above transition metal particle is ruthenium (Ru) and the above metal oxide is ATO (antimony doped tin oxide), The above metal oxide is SnO2, ruthenium (Ru) doped SnO in the catalyst layer. x (1≤x≤2) and Co-SnO x (0 <x≤2)(Co:Sn= 1:10~5:1) 금속간 산화물(Intermetallic oxide) 형태 중 어느 하나 이상의 형태를 갖는 염소 발생 반응용 촉매 구조물.

8. In paragraph 6, A catalyst structure for a chlorine generation reaction, wherein the content of antimony (Sb) contained in the above metal oxide is 0.1 at% to 5.0 at%.

9. In paragraph 3, A catalyst structure for a chlorine generation reaction, wherein the content of palladium (Pd) among the above transition metal particles is 0.1 at% to 5.0 at%.

10. In paragraph 3, A catalyst structure for a chlorine generation reaction, wherein the above catalyst structure is disposed at the bottom of the catalyst layer and further includes an interlayer containing a conductive material.

11. In paragraph 10, A catalyst structure for a chlorine generation reaction, wherein the above-mentioned conductive material is at least one selected from the group consisting of titanium (Ti) and tin (Sn).

12. In paragraph 10, A catalyst structure for a chlorine generation reaction, wherein the interlayer further comprises at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), palladium (Pd), aluminum (Al), tungsten (W), tantalum (Ta), antimony (Sb), and niobium (Nb).

13. In paragraph 10, A catalyst structure for a chlorine generation reaction, further comprising a metal oxide layer containing ruthenium oxide (RuO2) disposed between the catalyst layer and the interlayer.

14. An interlayer comprising at least one selected from the group consisting of titanium (Ti) and tin (Sn); and A catalyst structure for a chlorine generation reaction comprising a catalyst layer disposed on the intermediate layer and including nanoparticles containing cobalt oxide.

15. In paragraph 14, A catalyst structure for a chlorine generation reaction, wherein the catalyst layer further comprises transition metal particles comprising at least one selected from the group consisting of iridium (Ir), ruthenium (Ru), rhodium (Rh), platinum (Pt), and palladium (Pd) present on the surface of the nanoparticles.

16. In paragraph 10 or paragraph 14, The above intermediate layer is Ru a Sn b Ti c O d A catalyst structure for a chlorine generation reaction having a composition formula of (0 < a ≤ 0.4, 0 ≤ b ≤ 0.7, 0 ≤ c ≤ 0.7, a+b+c=1, d=2).

17. In paragraph 14, A catalyst structure for a chlorine generation reaction, further comprising a metal oxide layer containing ruthenium oxide (RuO2) disposed between the catalyst layer and the interlayer.

18. A step of preparing an antimony (Sb) precursor solution by dissolving the antimony (Sb) precursor in a mixed solvent of isopropyl alcohol (IPA) and water; A step of dispersing a tin (Sn) precursor in an antimony (Sb) precursor solution; A step of adding a solution containing a ruthenium (Ru) precursor dissolved therein to the antimony (Sb) and tin (Sn) precursor solution; and A method for producing a catalyst for a chlorine generation reaction, comprising the step of preparing a catalyst composition by adding a solution in which nanoparticles containing cobalt oxide are dispersed in isopropyl alcohol (IPA) to a solution in which an antimony (Sb) precursor, a tin (Sn) precursor, and a ruthenium (Ru) precursor are dissolved.

19. In paragraph 18, A method for producing a catalyst for a chlorine generation reaction, further comprising a step of ultrasonicating the catalyst composition after the step of preparing the catalyst composition.

20. In paragraph 18, A catalyst manufacturing method for a chlorine generation reaction in which the volume ratio of isopropyl alcohol (IPA) and water used in the above catalyst manufacturing method is 4:1 to 20:

1.

21. In paragraph 18, A method for producing a catalyst for a chlorine generation reaction, wherein the catalyst composition further comprises palladium (Pd) in an amount of 0.1 to 5 at% relative to 100 at% of the metal contained in the catalyst composition.

22. In paragraph 18, A method for producing a catalyst for a chlorine generation reaction, wherein the antimony (Sb) precursor is antimony trichloride (SbCl3), the tin (Sn) precursor is tin tetrachloride pentahydrate (SnCl4*5H2O), and the ruthenium (Ru) precursor is ruthenium acetylacetonate (Ru(acac)3).

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