Catalyst particles for hydrogen generation, method for preparing the same, and electrode comprising the same

Abstract

The present invention relates to catalyst particles for hydrogen generation, a method for manufacturing the same, and an electrode comprising the same. More specifically, it relates to catalyst particles for hydrogen generation having excellent durability and electrochemical properties, a method for manufacturing the same, and an electrode comprising the same.

Description

Technology Field

[0001] The present invention relates to catalyst particles for hydrogen generation, a method for manufacturing the same, and an electrode comprising the same. More specifically, it relates to catalyst particles for hydrogen generation having excellent durability and electrochemical properties, a method for manufacturing the same, and an electrode comprising the same. Background Technology

[0002] Electrochemical water splitting is a technology that converts electrical energy obtained from new and renewable energy into environmentally friendly hydrogen. The electrolysis of water is generally carried out in an acid or base electrolyte and includes the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER).

[0003] A representative technology for water electrolysis is Proton-exchange-membrane water electrolysis (PEMWE), which features the advantages of a small reactor and excellent energy efficiency. However, the electrochemical catalysts that can be used in PEMWE are limited to precious metals due to the oxygen evolution reaction. Therefore, Anion-exchange-membrane water electrolysis (AEMWE), which allows for the application of transition metals, is emerging as a new alternative technology.

[0004] Although platinum is primarily used as a catalyst in hydrogen evolution reactions, the reaction under basic conditions exhibits slower reaction kinetics than under acidic conditions due to the high energy barrier of the water dissociation step. Furthermore, platinum presents a problem in that its high cost limits its practical applications.

[0005] Therefore, in order to address the aforementioned problems, the inventors recognized the urgent need to develop a low-cost and high-efficiency platinum-substitute hydrogen generation catalyst and completed the present invention. Prior art literature

[0006] Republic of Korea Published Patent Application No. 10-2024-0079666

[0007] Confining Sub-Nanometer Pt Clusters in Hollow Mesoporous Carbon Spheres for Boosting Hydrogen Evolution Activity, Adv. Mater. 32 (2020) 1901349. The problem to be solved

[0008] The problem that the present invention aims to solve is to protect the core metal and lower the energy barrier for water splitting using porous titania (tiO₂). x The present invention provides a catalyst particle for hydrogen generation that includes ) as a shell and ruthenium as a core, which has superior catalytic activity compared to platinum and a cost advantage, and a method for manufacturing the same.

[0009] Another problem that the present invention aims to solve is to provide a hydrogen generation electrode comprising hydrogen generation catalyst particles having excellent durability and electrochemical properties.

[0010] The technical problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0011] To achieve the above objective, according to one aspect of the present invention, a catalyst particle for hydrogen generation is provided, comprising a ruthenium (Ru) metal core; a porous titania shell; and a molybdenum (Mo) metal located at the interface between the core and the shell.

[0012] According to another aspect of the present invention, a method for producing catalyst particles for hydrogen generation is provided, comprising: a step of hydrothermally reacting a first mixture comprising titanium dioxide (TiO2), a titanium precursor, and a molybdenum precursor to produce molybdenum-doped titanium oxide nanoparticles; a step of hydrothermally reacting a second mixture comprising the molybdenum-doped titanium nanoparticles and a ruthenium precursor to produce molybdenum-doped titanium-ruthenium oxide nanoparticles; a step of heat-treating the molybdenum-doped titanium-ruthenium oxide nanoparticles to produce core-shell structured composite oxide particles; and a step of electrochemically reducing the composite oxide particles.

[0013] According to another aspect of the present invention, a hydrogen generation electrode comprising the hydrogen generation catalyst particles is provided.

[0014] The technical problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art to which the present invention belongs from the description below. Effects of the invention

[0015] A catalyst particle for hydrogen generation and a method for manufacturing the same according to one embodiment of the present invention is a porous titania (tiO₂). x By including ) as a shell, it can protect the core metal and lower the energy barrier for water splitting to exhibit excellent catalytic activity. By including ruthenium (Ru) metal as a core, it can have superior catalytic activity compared to platinum and has a cost advantage, making it easy to apply to mass industries. Additionally, molybdenum metal is located at the interface between the core and the shell to receive electrons from the ruthenium metal and rapidly proceed with water splitting.

[0016] In addition, a hydrogen generation electrode comprising a hydrogen generation catalyst particle according to another embodiment of the present invention may have excellent durability and electrochemical properties.

[0017] The effects of the present invention are not limited to those described above, and unmentioned effects will be clearly understood by those skilled in the art from the present specification and the accompanying drawings. Brief explanation of the drawing

[0018] Figure 1 is an XPS (X-ray Photoelectron Spectroscopy) spectrum of particles before (Pre-HER) and after (Post-HER) the electrochemical reduction step when manufacturing hydrogen generation catalyst particles (Example 1) according to the present invention. FIG. 2 shows (a) a dark-field scanning transmission electron microscopy (HAADF-STEM) image and (b) a selected area electron diffraction (SAED) pattern of a hydrogen generation catalyst particle (Example 1) according to the present invention. Figure 3 is an EELS (Electron Energy Loss Spectroscopy) spectrum of a hydrogen generation catalyst particle (Example 1) according to the present invention. Figure 4 is the result of visually converting five line-scan profiles based on Energy Dispersive Spectroscopy (EDS) of the hydrogen generation catalyst particles (Example 1) according to the present invention. Figure 5 is an EDS (Energy Dispersive Spectroscopy) mapping image of a hydrogen generation catalyst particle (Example 1) according to the present invention. FIG. 6 is a schematic diagram showing the application of hydrogen generation catalyst particles (Example 1) according to the present invention to an anion-exchange-membrane water electrolysis device. Figure 7 is a graph confirming the current-voltage characteristics of an anion exchange membrane water electrolysis device to which the hydrogen generation catalyst particles (Example 1) according to the present invention are applied. Figure 8 is a graph confirming the breakdown voltage characteristics of an anion exchange membrane water electrolysis device to which the hydrogen generation catalyst particles (Example 1) according to the present invention are applied. FIG. 9 shows an anion exchange membrane water electrolysis device with a hydrogen generation catalyst particle (Example 1) according to the present invention applied thereto at 0.5 A / cm² 2 This is a graph confirming durability under current density and a temperature of 60 ℃. Specific details for implementing the invention

[0019] Specific details for implementing the present invention will be described in detail below with reference to the attached drawings.

[0020] When a part of the entire specification is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0021] Throughout the entire specification, when it is said that a component is located "on" another component, this includes not only cases where a component is in contact with another component, but also cases where another component exists between the two components.

[0022] Throughout the present specification, terms including ordinal numbers, such as “first” and “second,” are used for the purpose of distinguishing one component from another and are not limited by said ordinal number.

[0023] Throughout this specification, at% may represent an atomic percentage, wt% may represent a weight percentage or parts by weight, and mol% may represent a molar percentage.

[0024] In describing the principles of a preferred embodiment of the present invention in detail, if it is determined that a specific description of related known functions or configurations could unnecessarily obscure the essence of the present invention, such detailed description is omitted.

[0025] Catalyst particles for hydrogen generation, a method for manufacturing the same, and an electrode including the same

[0026] According to one aspect of the present invention, the invention comprises a ruthenium (Ru) metal core; porous titania (TiO₂). x The present invention provides a catalyst particle for hydrogen generation comprising a shell; and molybdenum (Mo) metal located at the interface between the core and the shell.

[0027] Hereinafter, the catalyst particles for hydrogen generation according to the present invention will be described in more detail.

[0028] According to one embodiment of the present invention, the catalyst particle for hydrogen generation is a reduction product of a composite oxide particle comprising a ruthenium dioxide core and a titanium dioxide shell doped with molybdenum metal.

[0029] More specifically, the hydrogen generation catalyst particle is a product obtained by electrochemical reduction reaction of a composite oxide particle comprising a ruthenium dioxide core and a molybdenum-doped titanium dioxide shell, wherein the ruthenium dioxide is reduced to ruthenium metal to form the core, and as the molybdenum-doped titanium dioxide is reduced, the molybdenum and titanium dioxide are separated to form porous titania (TiO₂). xA shell is formed, and the separated molybdenum is located at the interface between the core and the shell. At this time, the ruthenium metal core can exhibit superior catalytic activity compared to platinum as an active material for the catalyst particles, and the porous titania can protect the core metal and lower the energy barrier for water splitting, thereby increasing the activity of the catalyst.

[0030] According to one embodiment of the present invention, the ruthenium (Ru) metal core may have a particle size of 1.0 to 10 nm. If the above range is not satisfied, the specific surface area of ​​the ruthenium metal particles may decrease, thereby degrading the catalytic performance.

[0031] According to one embodiment of the present invention, the content of metal elements in the hydrogen generation catalyst particles may be 63 to 68 at% ruthenium; 30 to 35 at% titanium; and 2 to 6 at% molybdenum. The hydrogen generation catalyst particles having a metal element content within the aforementioned range can effectively improve electrochemical properties and can reduce process costs by including ruthenium, which is cheaper than platinum.

[0032] According to one embodiment of the present invention, the porous titania shell is composed of a single layer, and the thickness of the shell may be 0.2 to 0.8 nm, preferably 0.2 to 0.7 nm, more preferably 0.3 to 0.7 nm, even more preferably 0.3 to 0.6 nm, and most preferably 0.4 to 0.6 nm. By satisfying the shell thickness within the aforementioned range, excellent resistance to electrode corrosion can be achieved, and improved electrochemical properties can be expected.

[0033] The above titania is TiO x It can be explained as such, and the above x can be 0 to 2.

[0034] The hydrogen generation efficiency can be improved by including molybdenum (Mo) metal at the interface between the core and the shell in the above-mentioned catalyst particles for hydrogen generation. More specifically, the molybdenum metal receives electrons from the ruthenium metal, and as a result, the ruthenium metal atoms acquire a positive charge and react with negatively charged oxygen within the water molecules to improve the rate of water decomposition, thereby improving the hydrogen generation efficiency.

[0035] According to another aspect of the present invention, the present invention provides a method for producing catalyst particles for hydrogen generation, comprising: a step of hydrothermally reacting a first mixture comprising titanium dioxide (TiO2), a titanium precursor, and a molybdenum precursor to produce molybdenum-doped titanium oxide nanoparticles; a step of hydrothermally reacting a second mixture comprising the molybdenum-doped titanium nanoparticles and a ruthenium precursor to produce molybdenum-doped titanium-ruthenium oxide nanoparticles; a step of heat-treating the molybdenum-doped titanium-ruthenium oxide nanoparticles to produce core-shell structured composite oxide particles; and a step of electrochemically reducing the composite oxide particles.

[0036] First, the present invention comprises the step of hydrothermally reacting a first mixture comprising titanium dioxide (TiO2), a titanium precursor, and a molybdenum precursor to produce molybdenum-doped titanium oxide nanoparticles.

[0037] According to one embodiment of the present invention, the titanium precursor may be a titanium halide.

[0038] The above titanium halide may be a compound in which titanium is combined with one or more halogen elements selected from the group consisting of -F, -Cl, -Br and -I, and preferably, it may be a compound in which titanium is combined with -Cl.

[0039] According to one embodiment of the present invention, the molybdenum precursor may be a molybdenum halide.

[0040] The above molybdenum halide may be a compound in which molybdenum is combined with one or more halogen elements selected from the group consisting of -F, -Cl, -Br, and -I, and preferably, it may be a compound in which molybdenum is combined with -Cl. By applying the above molybdenum halide as a molybdenum precursor, solubility and thermal stability can be improved.

[0041] According to one embodiment of the present invention, the first mixture may be mixed with the titanium precursor and the molybdenum precursor in a molar ratio of 1:0.5 to 1.5, preferably in a molar ratio of 1:0.6 to 1.4, more preferably in a molar ratio of 1:0.7 to 1.3, even more preferably in a molar ratio of 1:0.8 to 1.2, and most preferably in a molar ratio of 1:0.6 to 1.1.

[0042] In one embodiment of the present invention, the hydrothermal reaction of the first mixture may be performed at a temperature of 150 to 200 ℃ for 10 to 15 hours. More specifically, the hydrothermal reaction of the first mixture may be performed preferably at a temperature of 160 to 200 ℃, more preferably at a temperature of 160 to 190 ℃, even more preferably at a temperature of 170 to 190 ℃, and most preferably at a temperature of 175 to 185 ℃. Additionally, the hydrothermal reaction of the first mixture may be performed preferably for 11 to 15 hours, more preferably for 11 to 14 hours, and even more preferably for 11 to 13 hours. By controlling the temperature and time of the hydrothermal reaction of the first mixture to the aforementioned ranges, molybdenum-doped titanium oxide nanoparticles produced thereby can be manufactured more stably and efficiently.

[0043] After the completion of the hydrothermal reaction of the first mixture, the method may further include the step of drying the molybdenum-doped titanium oxide nanoparticles; preferably, freeze-drying may be performed.

[0044] Next, the present invention comprises the step of hydrothermally reacting a second mixture comprising the molybdenum-doped titanium nanoparticles and a ruthenium precursor to produce molybdenum-doped titanium-ruthenium oxide nanoparticles.

[0045] In one embodiment of the present invention, the ruthenium precursor may be a compound in which ruthenium is combined with one or more halogen elements selected from the group consisting of -F, -Cl, -Br and -I, and preferably, it may be a compound in which ruthenium is combined with -Cl.

[0046] In one embodiment of the present invention, the hydrothermal reaction of the second mixture may be carried out at a temperature of 130 to 200 °C for 8 to 15 hours. More specifically, the hydrothermal reaction of the second mixture may be carried out preferably at a temperature of 140 to 200 °C, more preferably at a temperature of 150 to 200 °C, even more preferably at a temperature of 160 to 200 °C, and most preferably at a temperature of 170 to 200 °C. Additionally, the hydrothermal reaction of the second mixture may be carried out preferably for 8 to 14 hours, more preferably for 8 to 13 hours, even more preferably for 8 to 12 hours, and most preferably for 9 to 11 hours. By controlling the temperature and time of the hydrothermal reaction of the second mixture to the aforementioned ranges, molybdenum-doped titanium-ruthenium oxide nanoparticles can be manufactured more easily, and the cost of the entire process can be effectively reduced.

[0047] After the completion of the hydrothermal reaction of the second mixture, the method may further include the step of drying the molybdenum-doped titanium-ruthenium oxide nanoparticles; preferably, freeze-drying may be performed.

[0048] Next, the present invention comprises the step of heat-treating the molybdenum-doped titanium-ruthenium oxide nanoparticles to produce core-shell structured composite oxide particles.

[0049] In one embodiment of the present invention, the core-shell structured composite oxide particles may have a structure in which ruthenium dioxide (Ru2O) is the core and molybdenum metal (Mo) and titanium dioxide (TiO2) are the shells.

[0050] In this case, the molybdenum metal (Mo) and titanium dioxide (TiO2) shell is a single-layer shell in which molybdenum metal is doped onto titanium dioxide.

[0051] In one embodiment of the present invention, the heat treatment may be performed at a temperature of 150 to 250 ℃, preferably at a temperature of 160 to 240 ℃, more preferably at a temperature of 170 to 230 ℃, even more preferably at a temperature of 180 to 220 ℃, and most preferably at a temperature of 190 to 210 ℃. By controlling the heat treatment temperature to the aforementioned range, the molybdenum-doped titanium-ruthenium oxide nanoparticles can be effectively manufactured into core-shell structured composite oxide particles.

[0052] In addition, the heat treatment can be performed for 0.1 to 2 hours, preferably for 0.2 to 1.5 hours, more preferably for 0.3 to 1.2 hours, even more preferably for 0.4 to 1.1 hours, and most preferably for 0.5 to 1.0 hours. By controlling the heat treatment to the aforementioned range, the core-shell structured composite oxide particles can be effectively formed.

[0053] Next, the present invention can produce a catalyst particle for hydrogen generation according to the present invention by including the step of electrochemically reducing the composite oxide particle.

[0054] The above electrochemical reduction can be carried out by a hydrogen evolution reaction (HER).

[0056] A catalyst particle for hydrogen generation and a method for manufacturing the same according to one embodiment of the present invention is a porous titania (tiO₂). x By including ) as a shell, it can protect the core metal and lower the energy barrier associated with water splitting, thereby exhibiting excellent catalytic activity. By including ruthenium (Ru) metal as a core, it can have superior catalytic activity compared to platinum while having a cost advantage, making it easily applicable to mass industries.

[0057] According to another aspect of the present invention, the present invention provides a hydrogen generation electrode comprising the above-mentioned hydrogen generation catalyst particles.

[0058] More specifically, the hydrogen generation electrode may be an anode in which the hydrogen generation catalyst particles are deposited on a transition metal substrate with a thickness of 0.5 to 3.0 nm, preferably with a thickness of 0.7 to 2.8 nm, more preferably with a thickness of 1.0 to 2.5 nm, even more preferably with a thickness of 1.0 to 2.2 nm, and most preferably with a thickness of 1.0 to 2.0 nm, and may be applied by depositing on one surface of the transition metal.

[0059] The above transition metal is not limited to any type applicable as an anode, but may be one or more selected from the group consisting of titanium, nickel, cobalt, manganese, copper, zinc, iron, iridium, rhodium, palladium, silver, gold, and platinum.

[0060] A hydrogen generation electrode comprising a hydrogen generation catalyst particle according to another embodiment of the present invention may have excellent durability and electrochemical properties.

[0062] Hereinafter, the present invention will be described in detail with reference to examples to specifically explain the invention. However, the embodiments according to the present invention may be modified in various different forms, and the scope of the present invention is not to be interpreted as being limited to the embodiments described below. The embodiments of this specification are provided to more completely explain the present invention to those with average knowledge in the art.

[0063] Example 1.

[0064] A first mixture was prepared by mixing titanium dioxide (TiO2, P25, Aldrich, purity 99.5%) with 0.5 mmol TiCl4 (Aldrich, 499.0%) and 0.5 mmol MoCl5 (Aldrich, 99.99%), and molybdenum-doped titanium oxide nanoparticles were prepared by hydrothermally reacting the first mixture at 180 °C for 12 hours. Afterward, the solution after the hydrothermal reaction was cooled to room temperature, washed with distilled water five times at 5,000 rpm using a centrifuge, and freeze-dried the washed solution. Then, a second mixture was prepared by mixing 1 mmol RuCl3·3H2O (Aldrich, 99.98%) with the dried molybdenum-doped titanium oxide nanoparticles, and the second mixture was hydrothermally reacted at 180 °C for 10 hours to prepare molybdenum-doped titanium-ruthenium oxide nanoparticles. The molybdenum-doped titanium-ruthenium oxide nanoparticles were freeze-dried and heat-treated in a furnace at 200 °C for 40 minutes to prepare core-shell type composite oxide nanoparticles, wherein the core is ruthenium dioxide (Ru2O) and the shell is molybdenum metal (Mo) and titanium dioxide (TiO2). Next, the core-shell type composite oxide nanoparticles were electrochemically reduced by performing 10 cycles of a hydrogen evolution reaction to produce a ruthenium (Ru) metal core according to the present invention; A hydrogen generation catalyst particle was prepared comprising a porous titania shell and molybdenum (Mo) metal located at the interface between the core and the shell.

[0065] Experimental Example 1. Characteristics of Catalyst Particles

[0066] 1.1. XPS (X-ray Photoelectron Spectroscopy)

[0067] In order to confirm the chemical bonding state of elements before and after the electrochemical reduction step when manufacturing the hydrogen generation catalyst particles according to the present invention, the chemical bonding state of elements was measured using XPS (X-ray Photoelectron Spectroscopy, Versaprobe III, UL-PHI) in the Ti 2p and Ru 3p regions for the particles before (Pre-HER) and after (Post-HER) the electrochemical reduction step when manufacturing the hydrogen generation catalyst particles prepared in Example 1, and the bonding energy was corrected to the C 1s peak of 284.6 eV, and the results are as shown in Fig. 1.

[0068] Referring to FIG. 1, according to the present invention, the catalytic particles after the electrochemical reduction step (Post-HER) have a core in the ruthenium oxide (RuO2) state of the particles before the electrochemical reduction step (Pre-HER) reduced to metallic ruthenium (Ru), and at 461.1 eV, Ru 0 It can be confirmed that the peak intensity has increased. In addition, the catalyst particles after the electrochemical reduction step (Post-HER) are Ti 4+ It can be observed that the peak shifts toward lower binding energies, and through this, Ti 4+ Ions are partially dissolved and reduced to porous TiO x It can be seen that a shell has been configured.

[0069] 1.2. HAADF-STEM (high-angle annular dark-field scanning transmis-sion electron microscopy)

[0070] To confirm the morphology of the hydrogen generation catalyst particles according to the present invention, dark-field scanning transmission electron microscopy (HAADF-STEM) and selected area electron diffraction (SAED) were measured using a TEM (Themis Z, Thermo Fisher) at an acceleration voltage of 200 kV for the hydrogen generation catalyst particles prepared in Example 1, and the results are as shown in Fig. 2.

[0071] Referring to FIG. 2, (a) it can be observed that there are d-spacings corresponding to the (100), (101), and (002) planes of the hexagonal ruthenium (Ru) metal and the (101) plane of anatase TiO2. (b) Additionally, clear diffraction patterns corresponding to the ruthenium (Ru) metal and anatase TiO2 can be observed. These results indicate that molybdenum (Mo), which constituted the shell prior to electrochemical reduction, migrated from the surface toward the core, and through electrochemical reduction, porous TiO x This suggests that a single-layer shell has been formed.

[0072] 1.3. EELS (Electron Energy Loss Spectroscopy)

[0073] To confirm the characteristics of the porous TiOx constituting the shell of the hydrogen generation catalyst particles according to the present invention, Electron Energy Loss Spectroscopy (EELS) was measured using a TEM (Themis Z, Thermo Fisher) at an acceleration voltage of 200 kV for the hydrogen generation catalyst particles prepared in Example 1, and the results are as shown in Fig. 3.

[0074] Referring to FIG. 3, the Ti L-edge signal was partially observed in specific regions on the surface of the hydrogen generation catalyst particles, and its intensity varied depending on the location, which is because the shell of the hydrogen generation catalyst particles according to the present invention is a porous TiO x It can be said that this supports the existence of.

[0075] 1.4. 3D elemental distribution

[0076] To confirm the elemental distribution of the hydrogen generation catalyst particles according to the present invention, five line-scan profiles were visually digitized based on Energy Dispersive Spectroscopy (EDS) equipped with a TEM (Themis Z, Thermo Fisher) at an acceleration voltage of 200 kV for the hydrogen generation catalyst particles prepared in Example 1, and the results are as shown in Fig. 4.

[0077] Referring to FIG. 4, it can be confirmed that during the preparation of hydrogen generation catalyst particles according to the present invention, the composition of the metals present before and after the electrochemical reduction step—consisting of a ruthenium (Ru)-based core, a titanium (Ti)-based shell, and molybdenum (Mo) metal located at the interface between the core and the shell—remains unchanged. However, after electrochemical reduction (Post-HER), the titanium (Ti) intensity ratio in the core region decreases, indicating porous TiO x It can be seen that this strongly supports shell formation. In addition, it can be confirmed that the shell thickness is almost identical, at 0.45 nm and 0.48 nm before and after electrochemical reduction, respectively.

[0078] 1.5. Energy Dispersive Spectroscopy (EDS)

[0079] To confirm the elemental distribution of the hydrogen generation catalyst particles according to the present invention, Energy Dispersive Spectroscopy (EDS) mapping was performed on the hydrogen generation catalyst particles prepared in Example 1 at an acceleration voltage of 200 kV using EDS equipped with a TEM (Themis Z, Thermo Fisher), and the results are as shown in Fig. 5.

[0080] Referring to Fig. 5, (a) ruthenium (Ru) is mainly concentrated in the core of the catalyst particle (orange square), whereas Ti and O signals are distributed across the entire region of the catalyst particle, indicating that the ruthenium (Ru) core is TiO x It can be seen that this implies being surrounded by a shell. Additionally, (b)-(e) it can be confirmed that the content of metallic elements Ti, Ru, and Mo is 31.5, 64.2, and 4.3 at%, respectively. Through the above results, it can be seen that the hydrogen generation catalyst particles according to the present invention [reduce] TiO₂ by electrochemical reduction x It can be said that this supports the partial dissolution of the shell and the resulting formation of a porous shell.

[0081] Experimental Example 2. Water Electrolysis Characteristics

[0082] For the actual application of the hydrogen generation catalyst particles according to the present invention to anion-exchange-membrane water electrolysis, the hydrogen generation catalyst particles according to the present invention (Example 1) are deposited on Ti to a thickness of 1.5 nm and used as an anode, and an IrO2 cathode and a PiperION (Versogen) are used. TM A membrane electrode assembly (MEA) was manufactured using a membrane, and a schematic diagram of a water electrolysis device to which the membrane electrode assembly is applied is shown in Fig. 6.

[0083] 2.1. Current-Voltage Characteristics

[0084] To verify the current-voltage characteristics of an anion exchange membrane water electrolysis device to which the hydrogen generation catalyst particles according to the present invention are applied, the current-voltage characteristics were evaluated using a water electrolysis device to which a 1.0 M KOH electrolyte was applied to the manufactured membrane electrode assembly. In addition, to compare the electrochemical effects of the hydrogen generation catalyst particles according to the present invention, a comparative MEA was prepared by applying commercially available platinum catalyst particles (Pt / C) to the anode, and the current-voltage characteristics were verified using a comparative water electrolysis device to which a 1.0 M KOH electrolyte was applied, and the results are shown in Fig. 7.

[0085] Referring to FIG. 7, (a) a catalyst particle for hydrogen generation (Core-Shell Ru∥IrO₂) according to the present invention 2, The water electrolysis device with the blue line applied has 3.35 A / cm at a cell voltage of 2.0 V. 2 It can be confirmed that it exhibits a high current density. On the other hand, for a water electrolysis device using commercially available platinum condensed particles (Pt / C∥IrO₂, brown line), 1.22 A / cm² at the same cell voltage 2 It can be confirmed that it exhibits a lower current density. Based on the above results, it can be expected that when the hydrogen generation catalyst particles according to the present invention are applied, they can exhibit significantly superior electrochemical characteristics compared to currently commercially sold platinum catalyst particles.

[0086] 2.2. Breakdown Voltage Characteristics

[0087] To verify the electrochemical performance of a membrane electrode assembly to which hydrogen generation catalyst particles according to the present invention are applied, the manufactured membrane electrode assembly is at 1 A / cm 2 The contribution rates of the factors contributing to the overvoltage (voltage at 1 A - 1.23 V) in the current density were determined, and the results are as shown in Figure 8.

[0088] Referring to FIG. 8, it can be seen that the water electrolysis device with the hydrogen generation catalyst particles (Core-Shell Ru∥IrO2) according to the present invention and the water electrolysis device with the platinum catalyst particles (Pt / C∥IrO2) both have electrolyte resistance, oxidation electrode performance, reduction electrode performance, and mass transport (MT) as elements. However, it can be seen that the water electrolysis device with the hydrogen generation catalyst particles (Core-Shell Ru∥IrO2) according to the present invention has significantly higher reduction electrode performance compared to the water electrolysis device with the platinum catalyst particles (Pt / C∥IrO2), and through this, excellent performance can be expected for the hydrogen generation catalyst particles.

[0089] 2.3. Durability Characteristics

[0090] To verify the durability characteristics of a membrane electrode assembly to which hydrogen generation catalyst particles according to the present invention are applied, 0.5 A / cm² for the manufactured membrane electrode assembly (Core-Shell Ru∥IrO2) 2 Durability was investigated under current density and a temperature of 60°C, and the results are as shown in Fig. 9.

[0091] Referring to FIG. 9, (a) it can be seen that the initial cell voltage (1.65 V) of a membrane electrode assembly (Core-Shell Ru∥IrO2) with hydrogen generation catalyst particles according to the present invention increases slightly to 1.86 V at the start of operation, then stabilizes and remains stable for up to 430 hours with a low decomposition rate of 0.18 mV / h. The above results suggest that the initial increase in cell voltage may be attributed to membrane stabilization, while the slow increase over time is attributed to corrosion of the IrO2 cathode, indicating improved durability due to the hydrogen generation catalyst particles according to the present invention. (b) In addition, it can be seen that the membrane electrode assembly (Core-Shell Ru∥IrO2) with hydrogen generation catalyst particles according to the present invention exhibits nearly similar overvoltages before and after the durability test for 530 hours.

[0092] The above results can be interpreted as indicating the excellent stability of the hydrogen generation catalyst particles according to the present invention.

[0093] From the foregoing description, those skilled in the art to which the present invention pertains will understand that the present invention may be implemented in other specific forms without altering its technical concept or essential features. In this regard, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

Claim 1 A catalyst particle for hydrogen generation comprising a ruthenium (Ru) metal core; a porous titania shell; and a molybdenum (Mo) metal located at the interface between the core and the shell. Claim 2 In claim 1, the hydrogen generation catalyst particle is a reduction product of a composite oxide particle comprising a ruthenium dioxide core and a molybdenum-doped titanium dioxide shell. Claim 3 The hydrogen generation catalyst particles according to claim 1, wherein the metal element content of the hydrogen generation catalyst particles is ruthenium 63 to 68 at%; titanium 30 to 35 at%; and molybdenum 2 to 6 at%. Claim 4 A hydrogen generation catalyst particle according to claim 1, wherein the thickness of the porous titania shell is 0.2 to 0.8 nm. Claim 5 A method for producing catalyst particles for hydrogen generation according to claim 1, comprising: a step of hydrothermally reacting a first mixture comprising titanium dioxide (TiO2), a titanium precursor, and a molybdenum precursor to produce molybdenum-doped titanium oxide nanoparticles; a step of hydrothermally reacting a second mixture comprising the molybdenum-doped titanium nanoparticles and a ruthenium precursor to produce molybdenum-doped titanium-ruthenium oxide nanoparticles; a step of heat-treating the molybdenum-doped titanium-ruthenium oxide nanoparticles to produce core-shell structured composite oxide particles; and a step of electrochemically reducing the composite oxide particles. Claim 6 A method for manufacturing catalyst particles for hydrogen generation according to claim 5, wherein the titanium precursor and the molybdenum precursor in the first mixture are mixed in a molar ratio of 1:0.5 to 1.

5. Claim 7 A method for manufacturing catalyst particles for hydrogen generation according to claim 5, wherein the hydrothermal reaction of the first mixture is carried out at a temperature of 150 to 200 ℃ for 10 to 15 hours. Claim 8 A method for manufacturing catalyst particles for hydrogen generation according to claim 5, wherein the hydrothermal reaction of the second mixture is carried out at a temperature of 130 to 200 ℃ for 8 to 15 hours. Claim 9 A method for manufacturing catalyst particles for hydrogen generation according to claim 5, wherein the heat treatment is performed at a temperature of 150 to 250 ℃. Claim 10 A hydrogen generation electrode comprising hydrogen generation catalyst particles according to claim 1.

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