Electrocatalyst for brine electrolysis and manufacturing method thereof

Abstract

The present invention provides a method for manufacturing an electrocatalyst for brine electrolyte water electrolysis and an electrocatalyst for brine electrolyte water electrolysis manufactured thereby, comprising: a) a step of synthesizing a nickel-molybdenum oxide hydrate complex containing ruthenium by hydrothermally treating a solution containing a nickel (Ni) precursor, a molybdenum (Mo) precursor, and a ruthenium (Ru) precursor; and b) a step of forming a structure containing ruthenium-doped molybdenum oxide, ruthenium particles, and a nickel-molybdenum alloy by reducing heat treatment of the complex; wherein step b) is a step of exsolving at least a portion of the ruthenium, nickel, and molybdenum contained in the complex.

Description

Technology Field

[0001] The present invention relates to an electrocatalyst for brine electrolyte water electrolysis and a method for manufacturing the same, and more specifically, to an electrode catalyst for ensuring the activity and durability of a catalyst in a water electrolysis cell using brine as an electrolyte and a method for manufacturing the same. Background Technology

[0002] The technology of producing hydroxides, hydrogen, and chlorine by electrolyzing low-cost brine, such as seawater, is widely known. This electrolysis process (brine electrolysis or chloride-alkali process) can be considered a process whose performance and technological reliability have already been proven through decades of commercial operation.

[0003] Water electrolysis is largely a hydrogen generation reaction (HER, 2H + (aq) + 2e - → H2(g)) and oxygen evolution reaction (OER, 2H2O (l) → 4e - + 4H + It consists of two half-reactions: (aq) + O2(g)). To achieve high efficiency in water electrolysis, excellent electrode materials with low overpotential and durability are required. Although platinum (Pt) has been known as the best catalyst for HER, it is limited in terms of mass production and commercialization of hydrogen energy due to its limited reserves and high cost.

[0004] For this reason, ruthenium (Ru), which is cheaper than platinum yet exhibits similar levels of activity, is widely used as a constituent element in water electrolysis catalysts. Furthermore, many studies are being reported on the synthesis of catalysts using transition metals such as nickel (Ni) and molybdenum (Mo), which have the advantage of being abundant on Earth and significantly cheaper than precious metals. In particular, catalysts such as transition metal-based oxides and alloys are being actively researched as water electrolysis catalysts due to their excellent activity.

[0005] However, to ensure economic feasibility and efficiency during catalyst manufacturing, it is necessary to ensure that the active material is well exposed on the surface and to suppress the ionization of transition metals. Therefore, there is a need to develop catalysts applicable to the hydrogen evolution reaction (HER) that possess excellent catalytic activity and high durability. The problem to be solved

[0006] The present invention aims to solve such conventional problems by providing an electrocatalyst and a method for manufacturing the same that can lower the hydrogen generation reaction overpotential in brine electrolyte water electrolysis and suppress the degradation of durability caused by the ionization of metals. However, these problems are exemplary and the scope of the present invention is not limited by them. means of solving the problem

[0007] According to one aspect of the present invention, a method for manufacturing an electrocatalyst for brine electrolyte water electrolysis is provided.

[0008] The above method for manufacturing an electrocatalyst for brine electrolyte water electrolysis comprises: a) a step of synthesizing a ruthenium-containing nickel-molybdenum oxide hydrate complex by hydrothermally treating a solution containing a nickel (Ni) precursor, a molybdenum (Mo) precursor, and a ruthenium (Ru) precursor; and b) a step of forming a structure containing ruthenium-doped molybdenum oxide, ruthenium particles, and a nickel-molybdenum alloy by reducing heat treatment of the complex; wherein step b) may be a step of exsolving at least a portion of the ruthenium, nickel, and molybdenum contained in the complex.

[0009] According to one embodiment, in step a), the hydrothermal treatment may be performed at a temperature of 50°C to 300°C for 4 to 12 hours.

[0010] According to one embodiment, the reduction heat treatment in step b) may be performed under hydrogen gas and an inert gas.

[0011] According to one embodiment, in step b), the reduction heat treatment may be performed at a temperature of 300°C to 700°C for 5 minutes to 4 hours.

[0012] According to one embodiment, the nickel precursor may be one or more selected from the group consisting of nickel (II) nitrate hexahydrate (Ni(NO3)2·6H2O), nickel sulfate (NiSO4) and nickel chloride (NiCl2).

[0013] According to one embodiment, the molybdenum precursor is molybdenum diacetylacetonate dioxide (MoO2(acac)2) and ammonium heptamolybdate ((NH4)6Mo7O 24 It may be one or more types selected from a group consisting of ).

[0014] According to one embodiment, the ruthenium precursor may be one or more selected from the group consisting of ruthenium hexafluoride (RuF6), ruthenium (III) chloride (RuCl3), ruthenium (III) chloride hydrate (RuCl3·xH2O), ruthenium (III) bromide (RuBr3), ruthenium (III) bromide hydrate (RuBr3·xH2O), ruthenium iodide (RuI3), and ruthenium acetate salt.

[0015] According to another aspect of the present invention, an electrocatalyst for brine electrolyte water electrolysis is provided.

[0016] The above electrocatalyst for brine electrolyte water electrolysis may comprise ruthenium-doped molybdenum oxide manufactured by the above manufacturing method; ruthenium particles located between the crystal grains of the ruthenium-doped molybdenum oxide; and a nickel-molybdenum alloy located on the surface of the crystal grains of the ruthenium-doped molybdenum oxide.

[0017] According to one embodiment, the nickel-molybdenum alloy may be represented by [Chemical Formula 1], and the molybdenum oxide may be represented by [Chemical Formula 2].

[0018] [Chemical Formula 1]

[0019] Ni x Mo (where, 1≤x≤10)

[0020] [Chemical Formula 2]

[0021] MoO x (Here, 2≤x≤3)

[0022] According to one embodiment, the size of the ruthenium particles may be 0.1 nm to 3 nm.

[0023] According to one embodiment, the ruthenium-doped molybdenum oxide may be in a form where ruthenium is embedded in the surface of the molybdenum oxide. Effects of the invention

[0024] According to an embodiment of the present invention as described above, by using a nickel-molybdenum catalyst to which ruthenium elution is applied, the dissociation of water molecules in a brine electrolyte-based hydrogen generation reaction is promoted and the ionization of molybdenum elements is suppressed, thereby achieving the effect of securing high catalytic activity and durability.

[0025] Of course, the scope of the present invention is not limited by these effects. Brief explanation of the drawing

[0026] FIG. 1 is a process diagram illustrating the manufacturing process of an electrocatalyst for brine electrolyte water electrolysis according to an embodiment of the present invention. Figure 2 is an image of a scanning electron microscope (SEM) analysis of an electrocatalyst for brine electrolyte water electrolysis prepared according to an embodiment of the present invention. Figure 3 is an X-ray photoelectron spectroscopy (XPS) graph of an electrocatalyst for brine electrolyte water electrolysis according to an embodiment of the present invention. Figure 4 is a graph showing the results of an activity test for the hydrogen generation reaction of an electrocatalyst for brine electrolyte water electrolysis according to an embodiment of the present invention. Figure 5 is a graph showing the results of a durability test on the hydrogen generation reaction of an electrocatalyst for brine electrolyte water electrolysis according to an embodiment of the present invention. Figure 6 is a graph showing the results of an activity test for the hydrogen generation reaction of an electrocatalyst for brine electrolyte water electrolysis according to an embodiment of the present invention. Specific details for implementing the invention

[0027] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings. The embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art, and the following embodiments may be modified in various different forms, and the scope of the present invention is not limited to the following embodiments. Rather, these embodiments are provided to make the present disclosure more faithful and complete and to fully convey the spirit of the present invention to those skilled in the art. In addition, the thickness or size of each layer in the drawings is exaggerated for convenience and clarity of explanation.

[0028] FIG. 1 is a flowchart illustrating the manufacturing process of an electrocatalyst for brine electrolyte water electrolysis according to an embodiment of the present invention. Hereinafter, a method for manufacturing an electrocatalyst for brine electrolyte water electrolysis according to the present invention will be described with reference to FIG. 1.

[0029] First, a ruthenium-containing nickel-molybdenum oxide hydrate complex (e.g., Ru-incorporated NiMoO4·xH2O) is synthesized by hydrothermal treatment of a solution containing a nickel (Ni) precursor, a molybdenum (Mo) precursor, and a ruthenium (Ru) precursor.

[0030] The above nickel precursor may include one or more selected from the group consisting of nickel (II) nitrate hexahydrate (Ni(NO3)2·6H2O), nickel sulfate (NiSO4), and nickel chloride (NiCl2), and preferably may include nickel (II) nitrate hexahydrate (Ni(NO3)2·6H2O).

[0031] The above molybdenum precursor is molybdenum diacetylacetonate dioxide (MoO2(acac)2) and ammonium heptamolybdate ((NH4)6Mo7O 24 It may include one or more selected from the group consisting of ), preferably ammonium heptamolybdate ((NH4)6Mo7O 24 It may include ).

[0032] The above ruthenium precursor may include one or more selected from the group consisting of ruthenium hexafluoride (RuF6), ruthenium (III) chloride (RuCl3), ruthenium (III) chloride hydrate (RuCl3·xH2O), ruthenium (III) bromide (RuBr3), ruthenium (III) bromide hydrate (RuBr3·xH2O), ruthenium iodide (RuI3), and ruthenium acetate salt, and preferably may include ruthenium (III) chloride hydrate (RuCl3·xH2O).

[0033] The above nickel precursor, molybdenum precursor, and ruthenium precursor may be dissolved or dispersed in water, which is a solvent, and may be hydrolyzed by heat without separate additives.

[0034] The hydrothermal treatment of the solution containing the nickel (Ni) precursor, molybdenum (Mo) precursor and ruthenium (Ru) precursor can be performed at a temperature of 50°C to 300°C for 4 to 12 hours, and specifically, at a temperature of 100°C to 200°C for 5 to 7 hours.

[0035] In this way, a ruthenium-containing complex can be synthesized by hydrothermally reacting a nickel (Ni) precursor, a molybdenum (Mo) precursor, and a ruthenium (Ru) precursor without a separate pretreatment process.

[0036] Next, the above composite is subjected to reduction heat treatment.

[0037] In the present invention, a reduction heat treatment was performed to reduce the composite under high-temperature reducing conditions to induce the elution of ruthenium, nickel, and molybdenum.

[0038] At least a portion of the ruthenium, nickel, and molybdenum contained in the composite may be exsolved by the above reduction heat treatment. For example, the exsolved ruthenium (Exsolved Ru) particles are those in which a portion of the ruthenium element contained within the composite has been exsolved and exposed, thereby forming ruthenium particles.

[0039] The above reduction conditions are a hydrogen gas and an inert gas atmosphere, and the inert gas is one or more selected from the group consisting of nitrogen (N2), helium (He), and argon (Ar). In one embodiment, the reduction heat treatment can be performed under 5% (v / v) to 30% (v / v) H2 / Ar gas, and specifically under 10% (v / v) H2 / Ar gas.

[0040] The above heat treatment can be performed at a temperature of 300°C to 700°C for 5 minutes to 4 hours. If the temperature is below 300°C, it is undesirable because the ruthenium particles are not eluted, and if it exceeds 700°C, it is undesirable because the composite structure collapses.

[0041] Under the reduction heat treatment conditions described above, nickel and molybdenum dissolve into each other to form a nickel-molybdenum alloy represented by the following [Chemical Formula 1]. Accordingly, alloys of various compositions (NiMo, Ni2Mo, Ni 2.5 Mo, Ni3Mo, Ni4Mo and Ni 10Mo) can be formed.

[0042] [Chemical Formula 1]

[0043] Ni x Mo (where, 1≤x≤10)

[0044] In addition, molybdenum can form crystal particles in the form of molybdenum oxide represented by the following [Chemical Formula 2]. For example, MoO2 and MoO3 may be included.

[0045] [Chemical Formula 2]

[0046] MoO x (Here, 2≤x≤3)

[0047] As described above, at least a portion of ruthenium, nickel, and molybdenum is eluted by reduction heat treatment, and a structure containing ruthenium-doped molybdenum oxide, ruthenium particles, and a nickel-molybdenum alloy can be formed.

[0048] The eluted ruthenium particles are located between the molybdenum oxide and act as catalytic active sites, which can promote the dissociation of water (H2O) molecules in the water electrolysis cell. Meanwhile, the ruthenium particles remaining uneluted form ruthenium-doped molybdenum oxide and, together with the nickel-molybdenum alloy, form the framework of the structure itself, thereby maintaining a stable structure. Furthermore, the molybdenum oxide forms molybate (MoO4 2- It can inhibit ionization into molybate. Through this, the effect of securing high catalytic activity and durability can be achieved.

[0049] According to another aspect of the present invention, an electrocatalyst for brine electrolyte water electrolysis is provided.

[0050] The electrocatalyst for brine electrolyte water electrolysis according to the present invention refers to a catalyst comprising: ruthenium-doped molybdenum oxide; ruthenium particles located between the crystal grains of the ruthenium-doped molybdenum oxide; and a nickel-molybdenum alloy located on the surface of the crystal grains of the ruthenium-doped molybdenum oxide; and refers to a catalyst prepared by the hydrothermal treatment and reduction heat treatment described above.

[0051] Specifically, the above-mentioned electrocatalyst for brine electrolyte water electrolysis is a catalyst for the hydrogen evolution reaction (HER) in a water electrolysis cell using a liquid brine electrolyte.

[0052] For example, the above-mentioned electrocatalyst for brine electrolyte water electrolysis can be used at the cathode electrode in a water electrolysis cell.

[0053] As one embodiment, the nickel-molybdenum alloy may contain nickel and molybdenum in a molar ratio ranging from 1:1 to 10:1 and may be represented by [Chemical Formula 1] below. For example, alloys of various compositions (NiMo, Ni2Mo, Ni 2.5 Mo, Ni3Mo, Ni4Mo and Ni 10 Mo) may be included.

[0054] [Chemical Formula 1]

[0055] Ni x Mo (where, 1≤x≤10)

[0056] As an example, the molybdenum oxide may be represented by [Chemical Formula 2]. For example, MoO2 and MoO3 may be included.

[0057] [Chemical Formula 2]

[0058] MoO x (Here, 2≤x≤3)

[0059] As such, the electrocatalyst for brine electrolyte water electrolysis according to the present invention can obtain high activity for the hydrogen evolution reaction (HER) by including ruthenium-doped molybdenum oxide, a nickel-molybdenum alloy, and ruthenium particles.

[0060] The ruthenium particles located between the crystal grains of the ruthenium-doped molybdenum oxide may have a size of 0.1 nm to 3 nm. If the size is less than 0.1 nm, the ruthenium may not be able to function as an active site, and if it exceeds 3 nm, it may block catalytic activity by excessively covering the surface of the molybdenum oxide, which is undesirable.

[0061] The doped ruthenium remaining inside the above electrocatalyst can increase catalyst durability by inhibiting the ionization of molybdenum, and the ruthenium particles can increase catalytic activity by promoting the dissociation of water (H2O) molecules.

[0062] Specifically, the ruthenium-doped molybdenum oxide may be formed in such a way that at least a portion of the ruthenium is eluted and the ruthenium is embedded in the surface of the molybdenum oxide. This is distinct from a state in which the ruthenium is superficially placed on the surface of the molybdenum oxide particles. In this way, the ruthenium metal has a structure bonded to the surface of the molybdenum oxide crystal particles and can participate in the hydrogen generation reaction to produce a synergistic effect in terms of catalytic activity.

[0063] In addition, the ruthenium particles remaining unleached are molybdenum oxide molybate (MoO4 2- It can play a role in preventing ionization by being removed as molybate.

[0064] The present invention will be explained in more detail below with reference to examples. However, this is for illustrative purposes only and does not limit the scope of the present invention.

[0065] <Example>

[0066] First, in 50 ml of distilled water, 60 mM Ni(NO3)2·6H2O and (NH4)6Mo7O 24A reaction solution was prepared by mixing 20 mM RuCl3·xH2O and 1 mM RuCl3·xH2O. Then, hydrothermal synthesis was performed at 150°C for 6 hours. The composite obtained by hydrothermal synthesis was subjected to reduction heat treatment at 500°C for 1 hour in a 10% (v / v) H2 / Ar atmosphere. Through this process, a Ru NCs / Ni4Mo-MoO2 catalyst with eluted ruthenium was completed.

[0067] <Comparative Example>

[0068] 1. Comparative Example 1

[0069] 60 mM Ni(NO3)2·6H2O, (NH4)6Mo7O in 50 ml of distilled water 24 A reaction solution was prepared by mixing 20 mM. A nickel-molybdenum-based oxide was synthesized by hydrothermal synthesis of the reaction solution at 150°C for 6 hours. This was named Ni4Mo-MoO2.

[0070] 2. Comparative Example 2

[0071] The oxide obtained by hydrothermal synthesis in Comparative Example 1 above was immersed in a RuCl3 solution and then subjected to reduction heat treatment at 500°C for 1 hour in a 10% (v / v) H2 / Ar atmosphere. Through this, a Ru film / Ni4Mo-MoO2 catalyst with a ruthenium thin film applied to a nickel-molybdenum-based oxide was obtained.

[0072] 3. Comparative Example 3

[0073] A mixture of nickel powder, polyvinyl alcohol, and water was prepared in the form of foam using a mold. This was named Ni foam.

[0074] <Experimental Example>

[0075] 1. Surface shape evaluation

[0076] Figure 2 shows an image analyzed using scanning electron microscopy (SEM) to confirm the nanoparticle size of the catalyst synthesized in the above example.

[0077] In the image of Fig. 2, the Ru NCs / Ni4Mo-MoO2 catalyst has Ni4Mo particles distributed around MoO2 particles. Additionally, a structure in which Ru (~2 nm) particles are embedded between the boundaries of the MoO2 particles can be observed.

[0078] Figure 3 is an X-ray photoelectron spectroscopy (XPS) graph for analyzing the bonding structure on the catalyst surface. As a result, it was confirmed that ruthenium exists on the surface of the example catalyst with oxidation states of 0 and 4, respectively, and exists as ruthenium metal and ruthenium oxide (doping) on ​​the catalyst surface.

[0079] 2. Evaluation of Electrochemical Properties

[0080] All electrochemical characterizations were performed using a standard three-electrode cell system connected to an electrochemical workstation (Ivium). A mixed solution of 1 M KOH and 0.5 M NaCl, from which dissolved oxygen had been removed using nitrogen, was used as the electrolyte, and graphite and Ag / AgCl were used as the counter electrode and reference electrode, respectively. The fabricated catalyst was grown directly onto Ni foam and used as an electrode for characterization.

[0081] The electrochemical properties of the catalysts fabricated above were evaluated.

[0082] First, Figure 4 shows the results of comparing the HER characteristics of the catalysts. Figure 4(a) shows the LSV curve, and Figure 4(b) shows the current densities of -10, -100, and -1000 mA cm⁻¹ for each catalyst. -2 This is a bar graph comparing the overvoltage required to reach it.

[0083] In Fig. 4(a), when ruthenium elution was applied, the catalytic activity in brine increased, allowing for a higher current density to be obtained when the same voltage was applied. This appears to be because ruthenium can participate in water electrolysis or hydrogen generation reactions together with the nickel-molybdenum catalyst on the surface, creating a synergistic effect in terms of catalytic activity, and the ionization of molybdenum elements is suppressed by the doped ruthenium.

[0084] On the other hand, the catalysts of the comparative example have low electron density, so HER activity is reduced.

[0085] Through this, it can be seen that in the case of Comparative Example 1, the catalytic activity is lower than that of the catalyst in the example because it does not contain ruthenium elements. In the case of Comparative Example 2, the ruthenium thin film covers the nickel-molybdenum catalyst without being doped with ruthenium elements, so the nickel-molybdenum catalyst cannot participate in the water electrolysis reaction, which appears to be why the HER activity is low.

[0086] In FIG. 4(b), the catalyst of Comparative Example 1 has current densities of -10, -100, and -1000 mA cm⁻¹ -2 It requires 12, 45, and 220 mV, respectively, to reach [value], and the catalyst of Comparative Example 2 requires 12, 49, and 238 mV, respectively. The catalyst of the Example requires the lowest overpotential among the prepared catalysts, with values ​​of 9, 34, and 183 mV, respectively. In other words, it can be seen that the HER activity of the Ru-eluted catalyst is the best.

[0087] Figure 5 is a graph showing the results of a durability test on the hydrogen generation reaction of an electrocatalyst for brine electrolyte water electrolysis according to an embodiment of the present invention.

[0088] Comparing Figures 5(a) and (b), it can be seen that in the case of the catalyst of Comparative Example 1, the catalytic activity degraded after 3,000 cycles of reactivity testing, whereas in the case of the catalyst of the Example, the catalytic activity was maintained even after 5,000 cycles.

[0089] Additionally, in FIG. 5(c), the nickel-molybdenum catalyst to which ruthenium elution was applied according to the example has 100, 500 mA cm⁻¹ -2 It was confirmed that it exhibits high durability of over 200 hours even at high current densities.

[0090] Through this, it can be seen that in the case of a nickel-molybdenum catalyst with applied ruthenium elution, high catalytic activity and durability can be secured by promoting the dissociation of water molecules and suppressing the ionization of molybdenum elements in a brine electrolyte-based hydrogen production reaction.

[0091] Figure 6 is a graph showing the results of an activity test for the hydrogen generation reaction of an electrocatalyst for brine electrolyte water electrolysis according to an embodiment of the present invention.

[0092] When comparing the Tafel slopes of the catalysts prepared as shown in Fig. 6(a), the catalyst in the example shows a slope of 23 mV dec -1 It was the smallest at , and the catalysts in Comparative Examples 1 and 2 were 36 mV dec -1 , Comparative Example 3 catalyst at 144 mV dec -1 It was found that the comparative example catalyst had a relatively slow water splitting rate, whereas the example catalyst showed a significantly improved water splitting rate and the fastest electrochemical reaction rate on the catalyst surface.

[0093] Next, the charge transfer resistance of the catalysts was compared through EIS analysis, and the results are shown in Fig. 6(b). When comparing the charge transfer resistance of the prepared catalysts, the catalyst of the example had the lowest charge transfer resistance, which means that charge transfer from the catalyst surface is the fastest and activity is high. In the case of the catalyst of Comparative Example 2, although Ru was contained, it is suggested that the nickel-molybdenum catalyst was obscured on the surface, resulting in a high Tafel slope and charge transfer resistance.

[0094] Figure 6(c) shows the electrochemical active surface area, and the ECSA (= Cdl / Cs) value, which is the actual active area participating in the reaction, was compared with the value of Cdl. As a result, it was found that the highest actual active area was obtained when Ru elution was applied.

[0095] Figure 6(d) shows the turnover frequency (TOF), and the TOF value is an indicator of how quickly a reactant can be converted per unit site of the catalyst. Since the TOF value of the example is greater than that of Comparative Example 2, it can be seen that the catalytic activity of the example is superior.

[0096] According to an embodiment of the present invention as described above, by using a nickel-molybdenum catalyst to which ruthenium elution is applied, the dissociation of water molecules in a brine electrolyte-based hydrogen generation reaction is promoted and the ionization of molybdenum elements is suppressed, thereby achieving the effect of securing high catalytic activity and durability.

[0097] The present invention has been described with reference to the embodiments illustrated in the drawings, but this is merely illustrative, and those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom. Accordingly, the true technical scope of protection of the present invention should be determined by the technical spirit of the appended claims.

Claims

Claim 1 a) A solution containing a nickel (Ni) precursor, a molybdenum (Mo) precursor, and a ruthenium (Ru) precursor, 50 o C to 300 o a) synthesizing a ruthenium-containing nickel-molybdenum oxide hydrate complex by hydrothermal treatment at a temperature of C for 4 to 12 hours; and b) the complex at 300 o C to 700 o A method for manufacturing an electrocatalyst for brine electrolyte water electrolysis, comprising the step of forming a structure containing ruthenium-doped molybdenum oxide, ruthenium particles, and a nickel-molybdenum alloy by reducing heat treatment at a temperature of C for 5 minutes to 4 hours; wherein step b) is a step of exsolving ruthenium contained in the composite, and the ruthenium particles are located between the crystal grains of the ruthenium-doped molybdenum oxide, and the nickel-molybdenum alloy is located on the surface of the crystal grains of the ruthenium-doped molybdenum oxide. Claim 2 delete Claim 3 A method for manufacturing an electrocatalyst for brine electrolyte water electrolysis, wherein, in claim 1, the reduction heat treatment in step b) is performed under hydrogen gas and an inert gas. Claim 4 delete Claim 5 A method for manufacturing an electrocatalyst for brine electrolyte water electrolysis according to claim 1, wherein the nickel precursor is one or more selected from the group consisting of nickel(II) nitrate hexahydrate (Ni(NO3)26H2O), nickel sulfate (NiSO4), and nickel chloride (NiCl2). Claim 6 In claim 1, the molybdenum precursor is molybdenum diacetylacetonate dioxide (MoO2(acac)2) and ammonium heptamolybdate ((NH4)6Mo7O 24 A method for manufacturing an electrocatalyst for brine electrolyte water electrolysis, comprising one or more types selected from the group consisting of ). Claim 7 A method for manufacturing an electrocatalyst for brine electrolyte water electrolysis according to claim 1, wherein the ruthenium precursor is one or more selected from the group consisting of ruthenium hexafluoride (RuF6), ruthenium (III) chloride (RuCl3), ruthenium (III) chloride hydrate (RuCl3·xH2O), ruthenium (III) bromide (RuBr3), ruthenium (III) bromide hydrate (RuBr3·xH2O), ruthenium iodide (RuI3), and ruthenium acetate salt. Claim 8 An electrocatalyst for brine electrolyte water electrolysis, comprising: ruthenium-doped molybdenum oxide manufactured according to any one of claims 1, 3, 5 to 7; ruthenium particles located between the crystal grains of the ruthenium-doped molybdenum oxide; and a nickel-molybdenum alloy located on the surface of the crystal grains of the ruthenium-doped molybdenum oxide. Claim 9 An electrocatalyst for brine electrolyte water electrolysis according to claim 8, wherein the nickel-molybdenum alloy is represented by [Chemical Formula 1] and the molybdenum oxide is represented by [Chemical Formula 2]. [Chemical Formula 1] Ni x Mo (where, 1≤x≤10) [Chemical Formula 2]MoO x (Here, 2≤x≤3) Claim 10 An electrocatalyst for brine electrolyte water electrolysis according to claim 8, wherein the size of the ruthenium particles is 0.1 nm to 3 nm. Claim 11 In claim 9, the ruthenium-doped molybdenum oxide is an electrocatalyst for brine electrolyte water electrolysis in which ruthenium is embedded on the surface of the molybdenum oxide.

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