Chiral metal oxide-based anion exchange membrane water electrolysis device and manufacturing method therefor

Abstract

Provided are a chiral metal oxide-based anion exchange membrane water electrolysis device and a manufacturing method therefor. The chiral metal oxide-based anion exchange membrane water electrolysis device includes an L-type or D-type chiral metal oxide, which may possess chirality-induced spin selectivity, and thus, when used in a water electrolysis device including same, spin polarization may be controlled without an additional external magnetic field, and the efficiency of an electrode and the device may be improved.

Description

Chiral metal oxide-based anion exchange membrane water electrolysis device, and method for manufacturing the same

[0001] The present invention relates to a water electrolysis device, and more specifically, to a chiral metal oxide-based anion exchange membrane water electrolysis device and a method for manufacturing the same.

[0002] As hydrogen gains prominence as an alternative energy source to address environmental issues such as global warming, the demand for green hydrogen technology is rapidly increasing. Currently, one technology available for practical application is the production of green hydrogen using water electrolysis. Water electrolysis (WE) is a technology developed to convert water into hydrogen and oxygen. Water electrolysis can be broadly classified into conventional alkaline water electrolysis (CAWE) and polymer electrolyte membrane water electrolysis (PEMWE), which utilizes hydrogen ion exchange membranes (PEMs) or anion exchange membranes (AEMs). Recently, anion exchange membrane water electrolysis (AEMWE) has been gaining attention as a promising technology for future hydrogen production due to its applicability to inexpensive non-precious metal catalysts, hydrocarbon-based membranes, and alkaline solutions.

[0003] In particular, research is being conducted on metal oxide-based electrodes that can be used in anion exchange membrane water electrolysis devices. Metal oxides are very stable even under extreme conditions such as high temperatures, strong acids, and strong bases, and in particular, oxygen vacancies in metal oxides can improve the electrical conductivity of the material and facilitate the adsorption and conversion of water, thereby exhibiting high efficiency in oxygen and hydrogen production.

[0004] However, due to the characteristics of oxygen having a triplet-state spin structure, randomly arranged hydroxyl radicals are generated during the water electrolysis reaction, and hydrogen peroxide is produced as a reaction byproduct along with oxygen and hydrogen, which leads to a problem of reduced selectivity for the material and decreased water electrolysis efficiency. Accordingly, there is a need for performance improvement of the anion exchange membrane water electrolysis (AEMWE).

[0005] Chiral molecules (or chiral structures) can control spin without an external magnetic field due to the phenomenon where spins in one direction selectively pass through when electrons pass, caused by the interaction between the charge and the chiral molecule.

[0006] Accordingly, the present invention aims to provide a chiral metal oxide-based anion exchange membrane water electrolysis device that can suppress the generation of hydrogen peroxide, a reaction byproduct of an anion exchange membrane water electrolysis device, and improve the efficiency of the electrode by utilizing chirality, and a method for manufacturing the same.

[0007] The technical problems of the present invention are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below.

[0008] To achieve the above objective, one aspect of the present invention provides an anion exchange membrane water electrolysis device comprising: a first electrode including an L-type or D-type chiral metal oxide-based catalyst layer; a second electrode spaced apart from the first electrode; an anion exchange membrane provided between the first electrode and the second electrode; and an electrolyte filled within the first electrode, the anion exchange membrane, and the second electrode, wherein the chiral metal oxide is represented by the following chemical formula 1.

[0009] [Chemical Formula 1]

[0010] M 1 M 2O x

[0011] In the above chemical formula 1, the M 1 and the above M 2 is composed of two different metallic elements, and the above M 1 is any one selected from Co, Ni, and Mn, and said M 2 is the above M 1 It is a metal atom having an atomic radius that is greater than 0% and less than 15% of the difference from the atomic radius of, and x is an integer from 1 to 10.

[0012] The above M 2 It may be any one metal atom selected from Co, Mn, Ni, Li, Mg, Al, Sc, Ti, V, Cr, Fe, Cu, Zn, Ga, Ge, As, Se, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Sn, Sb, Te, Hf, Ta, W, Re, Os, Ir, Pt, Au, Bi, Po, At, U, Np, and Pu.

[0013] Specifically, the chiral metal oxide is CoMnO x , CoNiO x , NiCoO x , and NiMnO x It may include any one selected from among. More specifically, the chiral metal oxide is Co 1-y Mn y O x And, the above y may be 0.01 to 0.8. Preferably, the chiral metal oxide is Co 0.9 Mn 0.1 O x It could be.

[0014] The above porous transport layer may include one or more of metals, polymers, and carbon bodies.

[0015] The above anion exchange membrane comprises one or more polymers selected from poly(phenylene oxide), poly(ether ether ketone), poly(acryl ether sulfone), polybenzimidazole, polyimide, polystyrene, polylynorbornene, polyethylene, and polysiloxane, and on a backbone made of said polymer, among quaternary ammonium, imidazolium, benzimidazolium, piperidinium, guanidinium, phosphonium, sulfonium, and triazolium It may include one or more functional groups.

[0016] Another aspect of the present invention provides a method for manufacturing an anion exchange membrane water electrolysis device, comprising the steps of: mixing a metal oxide precursor, a chiral organic material, and an alkalizing agent to form a mixed solution; electrodepositing the mixed solution onto a substrate to form an L-type or D-type chiral metal oxide-based catalyst layer to form a first electrode; forming an anion exchange membrane on one side of the first electrode; forming a second electrode spaced apart from the first electrode and on one side of the anion exchange membrane; and filling the first electrode, the anion exchange membrane, and the second electrode with an electrolyte, wherein the chiral metal oxide is represented by the following chemical formula 1.

[0017] [Chemical Formula 1]

[0018] M 1 M 2 O x

[0019] In the above chemical formula 1, the M 1 and the above M 2 is composed of two different metallic elements, and the above M 1 is any one selected from Co, Ni, and Mn, and said M 2 is the above M 1 It is a metal atom having an atomic radius that is greater than 0% and less than 15% of the difference from the atomic radius of, and x is an integer from 1 to 10.

[0020] The above chiral organic material may be L-type tartaric acid or D-type tartaric acid.

[0021] The above alkalizing agents are sodium carbonate (Na2CO3), potassium carbonate (K2CO3), sodium bicarbonate (NaHCO3), and sodium phosphate (Na5P3O2). 10 It may include one or more selected from sodium pyrophosphate (Na4P2O7), disodium phosphate (K2HPO4), disodium phosphate (Na2HPO4), sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), trisodium citrate (C6Na3H5O7) and sodium metaphosphate (NaPO3)6).

[0022] The above substrate may be a porous transport layer.

[0023] The chiral metal oxide-based anion exchange membrane water electrolysis device of the present invention can control the direction of spins passing through according to the spin direction by forming an ion complex by adding a chiral organic material to an ion electrolyte in which a metal is dissolved and depositing it on a substrate by an electrodeposition method to form a metal oxide having a chiral structure.

[0024] By controlling the direction of the spin in this way, the water electrolysis efficiency of the water electrolysis device can be increased, and the generation of hydrogen peroxide during the water electrolysis reaction can be suppressed, thereby enabling the production of high-purity gas.

[0025] In addition, by forming the above chiral metal oxide-based catalyst layer on the porous transport layer to form an electrode, the transport of charge carriers and reactant gases through the porous transport layer can be facilitated during the operation of the water electrolysis device.

[0026] In addition, the method for manufacturing a chiral metal oxide-based anion exchange membrane water electrolysis device of the present invention forms a metal oxide using an electrodeposition method, thereby enabling uniform deposition regardless of the electrode size and allowing easy control of the electrode thickness, which can enable large-area production.

[0027] In addition, the characteristics of the manufactured chiral metal oxide-based anion exchange membrane water electrolysis device can be formed more uniformly.

[0028] The technical effects of the present invention are not limited to those mentioned above, and other unmentioned technical effects will be clearly understood by those skilled in the art from the description below.

[0029] FIG. 1 is a schematic diagram showing the structure of a chiral metal oxide-based anion exchange membrane water electrolysis device according to one embodiment of the present invention.

[0030] FIG. 2 is a schematic diagram showing the water electrolysis reaction mechanism and the oxygen evolution reaction (OER) process in a chiral metal oxide-based anion exchange membrane water electrolysis device according to one embodiment of the present invention.

[0031] FIG. 3 is a flowchart illustrating a method for manufacturing a chiral metal oxide-based anion exchange membrane water electrolysis device according to one embodiment of the present invention.

[0032] FIGS. 4(a) and FIGS. 4(b) show the L- / D-CoO of Preparation Example 1-1 of the present invention. x and L- / D-MnO of Preparation Example 1-11 x This is an image of a metal oxide thin film on an electrode.

[0033] FIG. 5 shows the L-Co of Preparation Examples 1-2 to 1-10 of the present invention. 1-yMn y O x (y=0.01, 0.05, 0.1, 0.15, 0.2, 0.25, 0.4, 0.6, and 0.8) This is an image showing a metal oxide thin film of an electrode.

[0034] FIGS. 6(a) to 6(c) are images showing the analysis results of the contact angles of the electrodes of Preparation Example 1-1 (Co 100%), Preparation Example 1-4 (Co 90% + Mn 10%), and Preparation Example 1-11 (Mn 100%) of the present invention.

[0035] Figure 7 is an image showing the thin film shapes of the electrodes of Preparation Examples 1-1 to 1-11 of the present invention and the control group (nickel foam) observed using a scanning electron microscope (SEM).

[0036] FIG. 8(a) is a graph showing the analysis of the electrodes of Preparation Examples 1-1 to 1-11 of the present invention using linear sweep voltammetry (LSV), and FIG. 8(b) is a graph showing the correlation between the contact angle and the overpotential required for the oxygen evolution reaction (OER) according to the ratio of manganese dopant (Mn dopant) of the electrodes of Preparation Examples 1-1 to 1-11 of the present invention.

[0037] FIGS. 9(a) to 9(c) show the L- / D-CoO of Preparation Example 1-1 of the present invention. x Electrode, L- / D-Co of Preparation Example 1-4 0.9 Mn 0.1 O x Electrode and L- / D-MnO of Preparation Example 11 x This is a graph showing the circular dichroism and UV-Vis spectrophotometric measurement data of the electrode.

[0038] FIG. 10 is Preparation Example 1-1 of the present invention (L- / D-CoO x ) Electrode and Preparation Example 1-4 (L- / D-Co 0.9 Mn0.1 O x This is a graph comparing the g-factors of the electrodes.

[0039] FIG. 11 is a graph showing the ratio of cobalt ions to manganese ions according to the manganese doping content of the electrodes of Preparation Example 1-3 (Mn 5), Preparation Example 1-4 (Mn 10), Preparation Example 1-5 (Mn 15), Preparation Example 1-6 (Mn 20), and Preparation Example 1-7 (Mn 25) of the present invention.

[0040] FIG. 12(a) is a schematic diagram of a measurement method using a magnetic conductive probe atomic force microscopy (mCP-AFM) according to an embodiment of the present invention, and FIG. 12(b) and FIG. 12(c) are of the L- / D-CoO of Preparation Example 1-1 of the present invention. x and L- / D-Co of Preparation Examples 1-4 0.9 Mn 0.1 O x This is a graph showing the chiral-induced spin selectivity of the electrode.

[0041] FIGS. 13(a) and FIGS. 13(b) show the L- / D-CoO of Preparation Example 1-12 of the present invention. x Electrode, Meso-CoO of Comparative Examples 1-3 x Electrode, L- / D-Co of Preparation Example 1-13 0.9 Mn 0.1 O x Electrode and Meso-Co of Comparative Examples 1-4 0.9 Mn 0.1 O x This is a graph showing the results of analyzing the extent of hydrogen peroxide generation via UV-Vis depending on the presence or absence of spin after the oxygen evolution reaction (OER) at the electrode.

[0042] FIGS. 14(a) to 14(c) show the electrodes (L-NiO) of Preparation Examples 1-14 to 1-20 of the present invention. x , L-Ni 0.9 Mn 0.1 O x , L-Ni 0.8 Mn 0.2 Ox , L-Ni 0.9 Co 0.1 O x , L-Ni 0.8 Co 0.2 O x , L-Co 0.9 Ni 0.1 O x , L-Co 0.8 Ni 0.2 O x This is a graph showing the result of analyzing ) using linear scanning potential (LSV).

[0043] FIG. 15 is the L-IrO of Preparation Example 1-21 of the present invention. x and D-IrO x This is an image showing the metal oxide thin film of the electrode.

[0044] FIG. 16(a) is an image showing nickel foam according to one embodiment of the present invention, and FIG. 16(b) is L-IrO of Preparation Example 1-22 of the present invention. x and D-IrO x This is an image showing the electrode.

[0045] FIG. 17 shows the L-IrO of Preparation Example 1-22 of the present invention. x and D-IrO x This is a graph showing the results of analyzing the electrode and control group (nickel foam) using linear scanning potentiometry (LSV).

[0046] Figure 18 is a graph showing the electrode of Manufacturing Example 2-1 of the present invention analyzed by linear scanning potential (LSV).

[0047] FIG. 19(a) shows the thin film shape of Preparation Example 2-7 of the present invention, and FIG. 19(b) is a graph showing the electrodes of Preparation Example 1-4, Preparation Example 1-5, Preparation Example 2-7, Preparation Example 2-8, and the control group (nickel foam) of the present invention analyzed by linear scanning potential (LSV).

[0048] FIG. 20 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) Electrode and Preparation Example 1-4 (L-Mn 0.1-Co 0.9 O x ) electrode and, (b) Preparation Example 1-11 (L-MnO x This is a graph showing the results of analyzing the electrode using X-ray photoelectron spectroscopy (XPS).

[0049] FIG. 21 is Preparation Example 1-1 of the present invention (L-CoO x ) Electrode, Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) electrode, and Preparation Example 1-11 (L-MnO x (a) UV-Vis spectrophotometric measurement results and (b) photoluminescence (PL) measurement results for the electrode.

[0050] FIG. 22 is Preparation Example 1-1 of the present invention (L-CoO x ) Electrode and Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x This is a graph showing the electrode analyzed by Raman spectroscopy.

[0051] FIG. 23 is Preparation Example 1-1 of the present invention (L-CoO x ) Electrode, Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) Electrode and Preparation Example 1-11 (L-MnO x (a) a graph showing the change in current density according to pH and (b) the change in slope of the efficiency according to pH at 1.6 V (vs. RHE), analyzed in electrolytes with various pH values.

[0052] FIG. 24 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) electrode and (b) Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O xThis is a graph showing the results of analyzing the electrodes using linear scanning potentiometry (LSV) in 1M KOH and 1M tetramethylammonium hydroxide (TMAOH), respectively.

[0053] FIG. 25 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) electrode and (b) Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x This is a graph showing the results of real-time Raman analysis (in situ Raman spectroscopy) performed by applying a voltage (0V to 1.7V) to the electrode in the electrolyte.

[0054] FIG. 26 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) electrode and (b) Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) electrode in 1M KOH solution and 100mA·cm -2 This is a graph showing the results of analyzing the potential over time under constant current conditions.

[0055] FIG. 27 is Preparation Example 1-1 of the present invention (L-CoO x ) Electrode and Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) electrode in 1M KOH solution and 500mA cm -2 This is a graph showing the concentration of dissolved cobalt ions (concentration of Co dissolution) after reacting for 10 hours under constant current conditions.

[0056] FIG. 28 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) electrode and (b) Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) electrode in 1M KOH solution and 500mA·cm -2 This is an image of the electrode surface observed with a scanning electron microscope (SEM) after reacting for 10 hours under constant current conditions.

[0057] FIG. 29 is a graph showing the normalized absorption at 400 nm of the L-SPL electrodeposited on the FTO glass substrate and the spray-coated L-Co3O4 thin film in Preparation Example 3-1 and Comparative Example 3-1 of the present invention.

[0058] FIG. 30 is a graph showing the work function of the electrodeposited L-SPL thin film and the spray-coated L-Co3O4 thin film of FIG. 29.

[0059] Figure 31 is a 3D plot of the work function measured in Figure 30.

[0060] FIG. 32 is Preparation Example 4-1 of the present invention (L-CoO x -PTL) and Preparation Example 4-2 (L-Co 0.9 Mn 0.1 O x -PTL) anode electrode, (a) graph showing the result of linear scanning potentiometry (LSV) analysis in 1M KOH heated to 80°C, (b) 1A cm in 1M KOH heated to 60°C -2 This is a graph showing the stability analysis under constant current conditions.

[0061] FIG. 33 is a graph showing the results of linear scanning voltammetry (LSV) measurements on the anodes of the nickel foam (Ni-foam 10mmX10mm) of Comparative Example 4-1 of the present invention and Manufacturing Example 4-1 (L-SP-PTL 10mmX10mm), Manufacturing Example 4-3 (L-SP-PTL 30mmX30mm), and Manufacturing Example 4-4 (L-SP-PTL 50mmX50mm) manufactured with various areas.

[0062] FIG. 34 is Manufacturing Example 4-4 of the present invention (large area (2500mm²) 2 L-SP-PTL (area = 100 mm) cut from the anode of ) L-SP-PTL) 2 This is the LSV curve of ).

[0063] FIG. 35 shows a 100 mm section cut from the electrodeposited large-area L-SPL of Preparation Example 3-2 of the present invention and the spray-coated large-area L-Co3O4 electrode of Comparative Example 3-2. 2This is the result of measuring the overvoltage of a thin film having an area.

[0064] FIG. 36 is a graph comparing the polarization curves of the anion exchange membrane water electrolysis device based on chiral L-NiFe-SP-PTL and D-NiFe-SP-PTL of Preparation Example 5-1 of the present invention and the anion exchange membrane water electrolysis device based on non-chiral meso-NiFe-PTL of Comparative Example 5-1.

[0065] FIG. 37 is an EIS Nyquist plot of an anion exchange membrane water electrolysis apparatus based on the chiral L-NiFe-SP-PTL and D-NiFe-SP-PTL of Preparation Example 5-1 of the present invention and the non-chiral meso-NiFe-PTL of Comparative Example 5-1.

[0066] FIG. 38 shows 1M KOH and 1A cm at 60°C for an anion exchange membrane water electrolysis apparatus based on the chiral L-NiFe-SP-PTL and D-NiFe-SP-PTL of Preparation Example 5-1 of the present invention and the achiral meso-NiFe-PTL of Comparative Example 5-1. -2 This is the result of a durability test performed using [method].

[0067] Hereinafter, embodiments according to the present invention will be described in detail with reference to the attached drawings.

[0068] While the present invention allows for various modifications and variations, specific embodiments are illustrated in the drawings and will be described in detail below. However, it is not intended to limit the invention to the particular forms disclosed, but rather the invention includes all modifications, equivalents, and substitutions consistent with the spirit of the invention as defined by the claims.

[0069] When elements such as layers, regions, or porous supports are referred to as existing "on" other components, it can be understood that this may exist directly on the other elements or that there may be an intermediate element between them.

[0070] Although terms such as first, second, etc., may be used to describe various elements, components, regions, layers, and / or regions, it will be understood that these elements, components, regions, layers, and / or regions should not be limited by these terms.

[0071]

[0072] Chiral metal oxide-based anion exchange membrane water electrolysis device

[0073] One aspect of the present invention can provide a chiral metal oxide-based anion exchange membrane water electrolysis device.

[0074] FIG. 1 is a schematic diagram showing the structure of an anion exchange membrane water electrolysis device according to one embodiment of the present invention.

[0075] Referring to FIG. 1, the anion exchange membrane water electrolysis device may be equipped with a first electrode (100) comprising an L-type or D-type chiral metal oxide-based catalyst layer. Depending on the embodiment, the first electrode (100) may function as a cathode or an anode. When the first electrode (100) acts as a cathode, water receives electrons to produce hydrogen gas (H2) and hydroxide ions (OH). - It can function as a hydrogen generating electrode responsible for the Hydrogen Evolution Reaction (HER), which is a reduction reaction that produces ). Alternatively, when the first electrode (100) functions as an anode, hydroxide ions (OH) generated at the cathode - It can function as an oxygen evolution electrode that promotes the Oxygen Evolution Reaction (OER), which is an oxidation reaction that releases electrons and generates water and oxygen gas (O2). In this embodiment, the case where the first electrode (100) is used as an anode is given as an example.

[0076] The above L-type or D-type chiral metal oxide is formed directly on the substrate and may not be accompanied by a separate conductive additive or binder.

[0077] The first electrode (100) may further include a porous transport layer (PTL) that supports the catalyst layer and is disposed on one side of the chiral metal oxide-based catalyst layer. That is, the first electrode (100) may include the catalyst layer and the porous transport layer on which the catalyst layer is formed. Accordingly, the L-type or D-type chiral metal oxide may be disposed on the surface of the porous transport layer and / or on the surface of the internal structure of the porous transport layer.

[0078] The porous transport layer may support the chiral metal oxide-based catalyst layer and support the chiral metal oxide-based catalyst layer. The porous transport layer may perform the function of transporting material to and from the first electrode (100). The porous transport layer may be in the form of a foam having a porous structure with a large specific surface area and an easy mass transfer pathway for reactants and products.

[0079] Specifically, for example, the porous transport layer may include one or more of metal, polymer, and carbonaceous material. More specifically, the porous transport layer may be a porous metal support in the form of foam or felt, comprising one or more of nickel (Ni), cobalt (Co), iron (Fe), titanium (Ti), tantalum (Ta), and alloys thereof. The porous transport layer may be a porous polymer structure comprising one or more of polyethylene, polypropylene, polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, and polyperfluoroalkyl vinyl ether. The porous transport layer may be a porous carbon structure comprising carbon paper or carbon cloth. In this embodiment, nickel foam (Ni foam) was used as the porous transport layer. The porosity of the nickel foam may be 50 to 200 PPI (Pores per inch), specifically 70 to 170 PPI, more specifically 110 PPI, but is not limited thereto.

[0080] The L-type or D-type chiral metal oxide-based catalyst layer may include chiral metal oxide nanoparticles (NP). According to an embodiment, the L-type or D-type chiral metal oxide-based catalyst layer may be disposed on the substrate in a zero-dimensional, one-dimensional, or two-dimensional structure. Specifically, the L-type or D-type chiral metal oxide-based catalyst layer may be provided on the substrate in the form of a thin film having a two-dimensional structure. In this case, the chiral metal oxide-based catalyst layer in the form of a thin film may have a thickness of 1 nm to 1 μm.

[0081] The L-type or D-type chiral metal oxide constituting the catalyst layer may exhibit chirality, and such chirality may be formed by transferring chiral properties to the metal oxide from an L-type or D-type chiral organic compound added during the manufacturing process. Chirality refers to asymmetry distinguishable from the mirror image of an object, and may exhibit molecular structures that cannot overlap each other in the mirror image. The L-type or D-type chiral metal oxide may refer to enantiomers of the metal oxide, namely L- and D-type isomers.

[0082] The above L-type or D-type chiral metal oxide is chiral and can have the characteristics of a spin filter, which is a chiral-induced spin-selectivity effect (CISS effect) that allows specific spins to pass through in the chiral direction and restricts spins in the opposite direction. Accordingly, the chiral metal oxide-based anion exchange membrane water electrolysis device of the present invention can effectively suppress hydrogen peroxide, a reaction byproduct formed during the operation of the anion exchange membrane water electrolysis device, and can increase the efficiency of oxygen and hydrogen generation.

[0083] The above L-type or D-type chiral metal oxide can be represented by the following chemical formula 1.

[0084] [Chemical Formula 1]

[0085] M 1 M 2 O x

[0086] In the above chemical formula 1, the M 1 and the above M 2 is composed of two different metallic elements, and the above M 1 is any one selected from Co, Ni, and Mn, and said M 2 is the above M 1 It is a metal atom having an atomic radius that is greater than 0% and less than 15% of the difference from the atomic radius of, and x is an integer from 1 to 10.

[0087] More specifically, metals with d-orbitals can have five d-orbital structures consisting of dz2, dx2-y2, dxy, dxz, and dyz. According to crystal field theory, when six ligands attempt to bind to the octahedral structure of the central metal, the energy levels of the dz and dx2-y2 orbitals can rise due to the interaction between the ligand electrons and the d-orbitals, which are the two relatively higher energy levels of the d-orbitals, known as equally degenerated (e g It is called ).

[0088] Furthermore, the dxy, dxz, and dyz orbitals can have relatively lower energy levels as the d orbitals bind slightly offset from the direction in which the ligand binds; this is referred to as the triply degenerated (t2g) d orbitals, which are three relatively low energy levels of the d orbitals. The difference between these two energy levels is the crystal field splitting energy (β o It is called ).

[0089] As such, depending on the crystal field splitting energy between the metal and the ligand and the oxidation state of the metal, e is a relatively high energy. g and t, which has relatively low energy 2g Spin comes into existence in it.

[0090] At this time, ligands that induce a strong field can form low-spin complexes because they have a smaller coupling energy and, according to Hund's rule, have a relatively smaller number of unpaired electrons.

[0091] Furthermore, since ligands that induce a weak field have a higher coupling energy, they have a larger number of unpaired electrons, so they do not satisfy Hund's rule and e having a higher energy level g Electrons can be placed there. In metal oxides, oxygen acts as a ligand forming a relatively weak field, with a small crystal field splitting energy (β). o The role of having ) to have a low-spin or high-spin state can be influenced by the oxidation state of the metal.

[0092] In addition, for electron transfer to occur more easily by increasing the overlap between oxygen (O) 2p orbitals and metal orbitals in the oxygen evolution reaction (OER) of the aforementioned anion exchange membrane water electrolysis device, e g t compared to a high-spin state where spin exists in (anti-bonding) 2g A low-spin state with spin can increase overlap with the oxygen (O) 2p orbital.

[0093] Accordingly, the present invention comprises the above-mentioned L-type or D-type chiral metal oxide to increase the oxygen evolution reaction (OER) by increasing overlap with the oxygen (O) 2p orbital through spin control. That is, M represented by the above-mentioned chemical formula 1 1 M 2 O xM of the above L-type or D-type chiral metal oxide 1 as cobalt (Co), nickel (Ni), It can be composed of any one metal atom selected from manganese (Mn). These may be metal atoms that exist in a low-spin state according to theoretical values ​​among metal atoms having d4-7 orbitals.

[0094] In addition, to enhance chirality, the present invention doped the L-type or D-type chiral metal oxide with metal atoms capable of further increasing lattice distortion. That is, M represented by Chemical Formula 1. 1 M 2 O x M of the above L-type or D-type chiral metal oxide 2 As mentioned above M 1 It can be doped with a metal element different from and. At this time, the above M 2 is the above M 1 It is possible to constitute metal atoms having an atomic radius that is greater than 0% and less than 15% of the difference from the atomic radius of. That is, the above M 1 The atomic radius of and the above M 2 The difference in the atomic radius of may be greater than 0% and less than 15%. The above M 1 M having an atomic radius within the range described above 2 The chiral lattice distortion of the L-type or D-type chiral metal oxide can be further increased by doping.

[0095] Specifically, for example, the above M 2may be any one metal atom selected from Co, Mn, Ni, Li, Mg, Al, Sc, Ti, V, Cr, Fe, Cu, Zn, Ga, Ge, As, Se, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Sn, Sb, Te, Hf, Ta, W, Re, Os, Ir, Pt, Au, Bi, Po, At, U, Np, and Pu. For this, reference may be made to the experimental examples described below.

[0096] In one embodiment, the M 1 When this is Co, Co 2+ The atomic radius of is 79 pm, and Co 3+ The atomic radius of can be 68.5 pm. Accordingly, the above M 2 It can be composed of metal atoms having an atomic radius of 58.23 pm or more and 90.85 pm or less.

[0097] Specifically, for example, the above L-type or D-type chiral metal oxide is CoMnO x , CoNiO x , NiCoO x , and NiMnO x It may include any one selected from among. More specifically, the L-type or D-type chiral metal oxide is Co 1-y Mn y O x And, the above y may be 0.01 to 0.8. Preferably, the L-type or D-type chiral metal oxide is Co 0.9 Mn 0.1 O x It could be.

[0098] The above anion exchange membrane water electrolysis device may further include a single-atom catalyst deposited on the L-type or D-type chiral metal oxide. The single-atom catalyst may be a single-atom catalyst used in anion exchange membrane water electrolysis devices. Specifically, for example, the above-mentioned single-atom catalyst may be one or more selected from transition metals, alkaline earth metals, and rare earth metals, and the above-mentioned single-atom catalyst may be one or more selected from Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Rb, Sr, Y, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Bi, Th, Pa, U, Pu, and Am, but is not limited thereto. More specifically, the above-mentioned single-atom catalyst may use one or more selected from ruthenium (Ru), iridium (Ir), platinum (Pt), silver (Ag), copper (Cu), and iron (Fe). Preferably, the above-mentioned single-atom catalyst may be iridium (Ir).

[0099] The anion exchange membrane water electrolysis device described above can exhibit circular dichroism in the range of 200 nm to 1000 nm. Circular polarization is light with a polarization state that possesses chirality and has a polarization form different from that of linear polarization, which is commonly known. The fact that the anion exchange membrane water electrolysis device of the present invention exhibits circular dichroism can be attributed to the effective transfer of chirality to the metal oxide by the chiral organic material during the manufacturing process. Additionally, the anion exchange membrane water electrolysis device may exhibit circular dichroism over a relatively wide wavelength range as its chirality is enhanced.

[0100] As described above, the anion exchange membrane water electrolysis device of the present invention has chiral-induced spin selectivity and can control spin polarization without an additional external magnetic field. In addition, the anion exchange membrane water electrolysis device can synthesize various chiral metal oxide structures of new structures having high activity by using various types of chiral organic materials and metal ions.

[0101] Referring to FIG. 1, the anion exchange membrane water electrolysis device may be provided with an anion exchange membrane (200) provided on one side of the first electrode (100). Specifically, the anion exchange membrane (200) may be provided between the first electrode (100) and the second electrode (300) described later. The anion exchange membrane (200) is an anion, specifically a hydroxide ion (OH-). - It can perform the role of ion transport that moves ) from the cathode to the anode. That is, the anion exchange membrane (200) can act as a solid electrolyte.

[0102] In addition, the anion exchange membrane (200) prevents the hydrogen gas generated at the cathode and the oxygen gas generated at the anode from mixing, and can be provided between the two electrodes to act as a barrier to prevent direct contact between them. Furthermore, according to an embodiment, the chiral metal oxide-based catalyst layer of the first electrode (100) may be bonded to one side of the anion exchange membrane (200), and in this case, the mechanical stability of the device may be increased.

[0103] Specifically, for example, the anion exchange membrane (200) is based on a polymer backbone composed of poly(phenylene oxide), poly(ether ether ketone), poly(acryl ether sulfone), polybenzimidazole, polyimide, polystyrene, polylynorbornene, polyethylene, and polysiloxane, and is one of quaternary ammonium, imidazolium, benzimidazolium, piperidinium, guanidinium, phosphonium, sulfonium, and triazolium It may include one or more.

[0104] Referring to FIG. 1, the anion exchange membrane water electrolysis device may be provided with a second electrode (300) spaced apart from the first electrode (100). That is, the first electrode (100) may be provided on one side and the second electrode (300) on the other side, centered on the anion exchange membrane (200). The second electrode (300) collects current and conducts electricity within the device together with the first electrode (100), and can perform the electrochemical reaction of decomposing water into hydrogen and oxygen separately. When the first electrode (100) is an anode, the second electrode (300) may act as a cathode, and when the first electrode (100) is a cathode, the second electrode (300) may act as an anode.

[0105] Specifically, for example, the second electrode (300) may have a structure similar to the first electrode (100) and may include an electrode catalyst and a support therefor. The support may include a carbon support such as carbon paper, porous carbon paper, carbon cloth, or porous carbon cloth, or a metal support such as a foam composed of Ni, Co, Fe, Ti, Ta, or an alloy thereof. The support may have a porous structure, and in this case, the support may also serve as a channel for material transport and electron transfer. The electrode catalyst may be applied differently depending on the type of the second electrode (300). For example, when the first electrode (100) is an anode and the second electrode (300) is a cathode, the electrode catalyst may be a hydrogen generation reaction catalyst, and specifically, for example, may include one or more of a metal, alloy, or metal oxide including Pt, Ru, Ni, Co, Fe, or Mn. In this embodiment, a material having a platinum-ruthenium alloy (PtRu) deposited on carbon paper was used as the second electrode (300).

[0106] Referring to FIG. 1, the anion exchange membrane water electrolysis device may be equipped with the first electrode (100), the anion exchange membrane (200), and an electrolyte (not shown) filled within the second electrode (300). The electrolyte may be a liquid electrolyte. Specifically, the electrolyte may include a neutral or basic (alkaline) solution. More specifically, the electrolyte may include one or more of water, an aqueous potassium hydroxide solution (KOH(aq)), an aqueous sodium hydroxide solution (NaOH(aq)), and sodium sulfate (Na2SO4(aq)). The aqueous potassium hydroxide solution and the aqueous sodium hydroxide solution may have a concentration of 0.1 to 1 M. The electrolyte contains hydroxide ions (OH) surrounding the anion exchange membrane (200). -The ion conductivity of the anion exchange membrane (200) can be improved by increasing the concentration. In addition, the electrolyte can provide an alkaline environment to increase the activity of the hydrogen generation reaction and the oxygen generation reaction.

[0107] As shown in FIG. 1, the anion exchange membrane water electrolysis device may have a stack structure, which is an assembly in which multiple unit cells composed of each component are stacked and connected in series. This stack structure facilitates securing the total voltage by connecting multiple unit cells in series, and allows for flexible expansion of output, such as increasing the number of cells to match the required hydrogen production volume according to the embodiment.

[0108] As shown in FIG. 1, the anion exchange membrane water electrolysis device may further be provided with a first end plate (711) and a second end plate (713) located on the outer side of the first electrode (100) and the second electrode (300), respectively. The first end plate (711) and the second end plate (713) are also called end plates and may be plates that mechanically support the entire structure at the outermost edge of the anion exchange membrane water electrolysis device, specifically the anion exchange membrane water electrolysis device. A plurality of bolt mounting grooves may be arranged on the first end plate (711) and the second end plate (713) to compress and seal each component.

[0109] Referring to FIG. 1, a first current collector (611) and a second current collector (613) may be further provided between the first electrode (100) and the first end plate (711), and between the second electrode (300) and the second end plate (713), respectively. The first current collector (611) and the second current collector (613) can perform the function of collecting electrical energy by efficiently transferring electrons between the electrodes (100, 300) and an external circuit. The first current collector (611) and the second current collector (613) may use non-precious metal-based metals such as nickel (Ni) or stainless steel (SUS), but are not limited thereto.

[0110] Referring to FIG. 1, a first gasket (411) and a second gasket (413) may be further provided between the first electrode (100) and the first current collector (611), and between the second electrode (300) and the second current collector (613), respectively. The first gasket (411) and the second gasket (413) can seal the electrodes (the first electrode (100) and the second electrode (300)) and the current collectors (the first current collector (611) and the second current collector (613)). Accordingly, the first gasket (411) and the second gasket (413) can prevent water and electrolyte, which are water electrolysis reactants, and hydrogen gas and oxygen gas, which are products, from leaking out or mixing with each other inside the device. Additionally, the first gasket (411) and the second gasket (413) may also function as insulators to prevent electrical short circuits between components. Specifically, for example, the first gasket (411) and the second gasket (413) may be made of rubber (elastomer) or polymer composites, but are not limited thereto.

[0111] Referring to FIG. 1, a first separator plate (511) may be further provided between the first gasket (411) and the first current collector (611). Additionally, a second separator plate (513) may be further provided between the second gasket (413) and the second current collector (613). The separator plates (511, 513) are also called bipolar plates and can perform an electrical role of receiving current generated at the cathode and transmitting it to the anode. Specifically, for example, when the anion exchange membrane water electrolysis device is implemented as a stack structure by stacking multiple unit cells including an anode, a cathode, and an anion exchange membrane disposed between them, the separator plates (511, 513) can transmit current generated at the cathode of one cell to the anode of the next adjacent cell, thereby enabling multiple unit cells to be connected in series. In addition, the separator plates (511, 513) can physically separate adjacent unit cells, thereby preventing hydrogen and oxygen, which are water electrolysis products, from mixing.

[0112] FIG. 2 is a schematic diagram illustrating the water electrolysis reaction mechanism and the oxygen evolution reaction (OER) process in a chiral metal oxide-based anion exchange membrane water electrolysis device according to one embodiment of the present invention. As illustrated in FIG. 2, SP-PTL may refer to the first electrode (100) comprising the chiral metal oxide-based catalyst layer and the porous transport layer on which the catalyst layer is formed. In FIG. 2, the first electrode (100) is described as acting as an anode, and the second electrode (300), composed of an electrode catalyst (310) and a support (320), is described as acting as a cathode.

[0113] The following equations (1) to (3) are equations for the OER at the anode and the HER at the cathode in the anion exchange membrane water electrolysis device of the present invention, and the overall reaction equation.

[0114] OER : 4OH -→ O2 + 2H2O + 4e - (E0=1.23 V vs. RHE) … … Equation (1)

[0115] HER : 4H2O + 4e - → 2H2+ 4OH - (E0=0 V vs. RHE) … … Equation (2)

[0116] Overall: 2H2O → 2H2+ O2(E0= 1.23 V vs. RHE) … … Equation (3)

[0117] Looking at the above equations (1) to (3), OER is OH - Since the transfer of an intermediate and four electrons is required, it can be a rate-limiting step.

[0118] As shown in Fig. 2, electrons OH - As it is transferred from the anode, only one specific spin state carrier can pass through the first electrode (100) which is spin-polarized (spin polarized-porous transport layer, SP-PTL), and thus the first electrode (100) can perform the role of a spin filter.

[0119] This initial reaction can be expressed as shown in the following equation (4) (for simplification, considering only one specific spin state due to spin polarization, M(↓)- * Indicated by O(↑). OH of the electrolyte - Since it can have both ↓ and ↑ spin states, the adsorbed OH - The spin state of is not considered.

[0120] M(↓)- * O(↑) + OH - → M(↓)- * O(↑)O(↑)H + (↓)e - … … Equation (4)

[0121] As shown in the above equation (4), the spin states of the newly generated ·OH radicals by electron transfer can be maintained parallel to each other. The above equation (4), which represents the initial reaction, induces spin polarization. * A triplet state intermediate of the O(↑)O(↑)H species can be produced. Subsequently, the hydrogen atom (H) is M(↓)- in the electrolyte according to the following formula (5). * O(↑)O(↑)H and OH - It can be removed by the reaction.

[0122] M(↓)- * O(↑)O(↑)H +OH - → M(↓)- * O(↑)-O(↑)+ H2O + (↓)e - … … Equation (5)

[0123] In the above equation (5), if the spins are randomly oriented, H2O2 formation * O(↑)O(↑)H and * It can be energetically favored through reactions between opposite spin states of O(↑)O(↓)H. However, spin control induced by the aforementioned CISS effect can prevent such reactions. Subsequent transfer reactions can be promoted by suppressing H2O2 generation. That is, these reactions involve adsorbed OH - It is independent of the spin state, and H2O formation occurs between completely occupied H and OH - It occurs due to the reaction between them, and can have both (↑) and (↓) spin states. Furthermore, the CISS effect occurs only at the catalyst surface, and OH in the electrolyte. - Since it does not affect the spin configuration of, such a spin-independent reaction as in the above equation (5) can occur in any situation.

[0124] The triplet intermediate spontaneously becomes triplet O2 in the following equation (6) 3 It can be converted to O2) and can take the form of the following formula (7).

[0125] M(↓)- *O(↑)-O(↑) → M(↓) + 3 O2… … formula(6)

[0126] M(↓)+O(↑)H- → M(↓)- * O(↑)H+(↓)e - … … Equation (7)

[0127] Finally, as shown in the following equation (8), the catalytic active site can be returned to its initial state by the reaction.

[0128] M(↓)- * O(↑)H+ OH - → M(↓)- * O(↑)+ H2O +(↓)e - … … Equation (8)

[0129] According to the spin-polarized oxygen evolution (OER) mechanism presented in Fig. 2, the generation of ground-state triplet oxygen (O(↑)-O(↑)) is favorable. In carrier spin polarization, since two or three hydroxyl anions with spin-parallel alignment are unlikely to react with each other, triplet oxygen (which requires four hydroxyl anions) 3 The generation of O2) may be preferred. This alignment is also preferred because the four hydroxyl anions do not easily interact due to their parallel spins, so singlet oxygen ( 1 The possibility of O2 formation can be reduced. However, if there is no spin polarization of the reaction intermediate, the formation of H2O2 requires only two hydroxyl anions in the singlet state (including paired electrons), so singlet oxygen ( 1There is a higher probability that O2) and hydrogen peroxide (H2O2) (HO(↑)-(↓)OH) will be generated. In this case, 1.76 V (reversible hydrogen electrode, RHE) is required for the formation of singlet H2O2, which may be higher than the energy required for the formation of triplet O2 (1.23 V vs. RHE). Therefore, by suppressing the formation of H2O2 through the chiral-induced spin selectivity (CISS effect) of the L-type or D-type chiral metal oxide-based electrode of the present invention and generating triplet oxygen through an electron pathway, the total overpotential can be reduced and the number of electrons available for water electrolysis can be increased, thereby increasing the hydrogen fuel production efficiency of an anion exchange membrane water electrolysis device to which this is applied.

[0130]

[0131] Method for manufacturing a chiral metal oxide-based anion exchange membrane water electrolysis device

[0132] Another aspect of the present invention may provide a method for manufacturing a chiral metal oxide-based anion exchange membrane water electrolysis device. This may be a method for manufacturing the chiral metal oxide-based anion exchange membrane water electrolysis device described above.

[0133] FIG. 3 is a flowchart illustrating a method for manufacturing a chiral metal oxide-based anion exchange membrane water electrolysis device according to one embodiment of the present invention.

[0134] Referring to FIG. 3, first, the method for manufacturing the chiral metal oxide-based anion exchange membrane water electrolysis device may form a mixed solution by mixing a metal oxide precursor, a chiral organic material, and an alkalizing agent (S100).

[0135] Specifically, the chiral metal oxide can be represented by the following chemical formula 1.

[0136] [Chemical Formula 1]

[0137] M 1 M 2 O x

[0138] In the above chemical formula 1, the M 1 and the above M 2 is composed of two different metallic elements, and the above M 1 is any one selected from Co, Ni, and Mn, and said M 2 is the above M 1 It is a metal atom having an atomic radius that is greater than 0% and less than 15% of the difference from the atomic radius of, wherein x is an integer from 1 to 10. Specifically, M 2 It may be any one metal atom selected from Co, Mn, Ni, Li, Mg, Al, Sc, Ti, V, Cr, Fe, Cu, Zn, Ga, Ge, As, Se, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Sn, Sb, Te, Hf, Ta, W, Re, Os, Ir, Pt, Au, Bi, Po, At, U, Np, and Pu.

[0139] Specifically, the step of preparing the mixed solution may include a process of preparing a solution containing the alkalizing agent, a process of mixing the metal ion and the alkalizing agent into the solution, and a process of mixing the chiral organic material into the solution.

[0140] The metal oxide precursor may be a precursor comprising one or more of transition metals, alkaline earth metals, and rare earth metals. Specifically, the metal oxide precursor may comprise one or more metals selected from Co, Mn, Ni, Li, Mg, Al, Sc, Ti, V, Cr, Fe, Cu, Zn, Ga, Ge, As, Se, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Sn, Sb, Te, Hf, Ta, W, Re, Os, Ir, Pt, Au, Bi, Po, At, U, Np, and Pu. More specifically, the metal oxide precursor may comprise at least four of cobalt (Co), nickel (Ni), and manganese (Mn). That is, the chiral metal oxide is CoMnO x , CoNiO x , NiCoO x , and NiMnO x It may include any one selected from among. Preferably, the chiral metal oxide is Co 1-y Mn y O x And, the above y may be 0.01 to 0.8. More preferably, the chiral metal oxide is Co 0.9 Mn 0.1 O x It could be.

[0141] The above chiral organic material may be a chiral ligand that transfers chirality to the metal oxide produced by forming an ionic complex with the above metal oxide precursor, and may be an organic material having chirality. The above chiral organic material may be an L-type chiral organic material and a D-type chiral organic material, respectively, depending on the sample. The above L-type chiral organic material and D-type chiral organic material may refer to enantiomers of the chiral organic material, that is, L- and D-type isomers.

[0142] That is, the above L-type or D-type chiral metal oxide may be formed as a chiral metal oxide through the transfer of chiral properties via the formation of a complex between a chiral organic and a metal ion constituting the metal oxide. In other words, a chiral organic having L-type or D-type chirality acts as a chiral ligand and binds to the surface of the metal oxide nanoparticle, causing its structural symmetry to collapse and the crystal structure to become distorted. Consequently, the metal oxide nanoparticle may align in a specific direction, and a transfer of chiral properties may occur.

[0143] Specifically, for example, the above chiral organic material is tartaric acid, amino acid, sugar, phenylalanine, valine, cysteine, glutamate, serine, threonine, leucine, isoleucine, tyrosine, tryptophan, proline, methionine, asparagine, glutamine, glutathione, aspartic acid, glutamic acid, arginine, lysine, histidine, ornithine, glyceraldehyde, glucose, Alanine, Ribose, Fructose, Erythrose, Threose, Arabinose, Xylose, Lyxose, Talose, Galactose, Gulose, Allose, Altrose, Idose, Mannose, Methylbenzylamine (C6H5CH(CH3)NH2), 2-amino-3-methylbutane (C5H 13 N), ethylbenzylamine (C6H5CH(C2H5)NH2), 3,3-dimethyl-2-butylamine (((CH3)3C)CH(NH2)CH3), 1-cyclohexylethylamine (C6H 11 CH(CH3)NH2), 1-(1-naphthyl)ethylamine(C 10 H7CH(CH3)NH2), sec-butylamine(CH3CH2CH(NH2)CH3), 1-(2-naphthyl)ethylamine(C 12 H 13N), fluoromethylbenzylamine (FC6H4CH(CH3)NH2), chloromethylbenzylamine (ClC6H4CH(CH3)NH2), bromomethylbenzylamine (BrC6H4CH(CH3)NH2), iodomethylbenzylamine (IC6H4CH(CH3)NH2), 1,2,3,4-tetrahydro-3-isoquinolinecarboxylic acid (C 10 H 11 NO2), 3-cyclohexene-1-carboxylic acid (C7H 10 O2), 3-amino-1-quadrubutyloxycarbonyl-piperidine(C 10 H2ON2O2), 1,2,3,4-tetrahydro-1-naphthylamine((C 10 H 11 )NH2), 1-aminoindene(C9H 11 N), 1-amino-2-(methoxymethyl)pyrrolidine(C6H 14 N2O), 1-cyclopropylethylamine (C5H 11 N), bornylamine (C 10 H 19 N), 1-(m-tolyl)etheneamine (C9H 13 N), (S)-1,4-benzodioxane-2-carboxylic acid (C9H8O4), 1-methoxy-2-propylamine (CH3OCH2CH(CH3)NH2), (S)-1,2,3,4-tetrahydro-1-naphthoic acid (C 12 H 14 O2), 1-methyl-3-phenylpropylamine(C6H5CH2CH2CH(NH2)CH3), (R)-(-)-1,2,3,4-tetrahydro-1-naphthylamine((C 10 H 11 )NH2), 1-amino-2-propanol(CH3CH(OH)CH2NH2), (R)-(+)-1,2-dithiolan-3-pentanoic acid(C8H 14 O2S2), (S)-1-Boc-4-oxopiperidine-2-carboxylic acid(C 11 H 17 NO5), β-methylphenylamine (C6H5CH(CH3)CH2NH2), 2-methylpiperidine (C6H 13 N), 3-quinuclideinol (C7H 13 NO), and 3-aminopiperidine (C5H 12It may include one or more selected from N2).

[0144] More specifically, the chiral organic material may be L-type tartaric acid or D-type tartaric acid. When using tartaric acid (or a tartaric acid derivative) as the chiral organic material, L-type and D-type may be used separately or in combination; however, in the present invention, it may be preferable to use them separately without mixing them. This may be because the optical purity value when the L-type tartaric acid and the D-type tartaric acid are used in combination may be lower than when the L-type tartaric acid and the D-type tartaric acid are used separately.

[0145] The above alkalizing agents are sodium carbonate (Na2CO3), potassium carbonate (K2CO3), sodium bicarbonate (NaHCO3), and sodium phosphate (Na5P3O2). 10 It may include one or more selected from sodium pyrophosphate (Na4P2O7), disodium phosphate (K2HPO4), disodium phosphate (Na2HPO4), sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), trisodium citrate (C6Na3H5O7), and sodium metaphosphate (NaPO3)6). In this embodiment, sodium carbonate (Na2CO3) was used as the alkalizing agent.

[0146] Next, the above-mentioned mixed solution can be electrodeposited onto a substrate to form an L-type or D-type chiral metal oxide-based catalyst layer, thereby providing a first electrode (S200). That is, the L-type or D-type chiral metal oxide-based catalyst layer can be formed on the substrate using the above-mentioned electrodeposition.

[0147] Conventional methods for fabricating chiral metal oxide electrodes include hydrothermal synthesis and self-assembly monolayer methods. Hydrothermal synthesis has limitations, such as a very restricted application area due to the use of specialized synthesis equipment, the necessity of high temperature and pressure conditions, and extremely long synthesis times. Additionally, the self-assembly monolayer method may be limited in its application due to the long synthesis time required and limitations in controlling electrode thickness. Other methods for electrode deposition include chemical vapor deposition (CVD) and physical vapor deposition (PVD); however, these require expensive deposition equipment, making it somewhat difficult to fabricate chiral metal oxide electrodes using these technologies.

[0148] To solve this, the present invention can provide a method for synthesizing a first electrode based on a chiral metal oxide at room temperature by electrodeposition (electrochemical deposition), which can utilize various metal ions without expensive deposition equipment or complex processes like conventional deposition methods. That is, by forming a chiral metal oxide-based anion exchange membrane water electrolysis device using an electrodeposition method, the use of chiral organic materials and metal ions can be facilitated.

[0149] Accordingly, the present invention can provide a chiral metal oxide-based anion exchange membrane water electrolysis device with a uniform thickness on any conductor, regardless of the shape of the porous support. In addition, by introducing one or more materials, it is possible to control the characteristics of the electrode, and since uniform deposition is possible regardless of the electrode size, it is very easy to scale up to a large area and exhibit uniform characteristics. Furthermore, since deposition is performed while maintaining the shape of the electrode structure, deposition can be performed without deformation.

[0150] The chiral metal oxide-based catalyst layer described above can be formed with a thickness of 1 nm to 1 µm. When configured within the above range, it can be easily made into an anion exchange membrane water electrolysis device, and the effect due to chirality can be increased through an appropriate thickness.

[0151] After the step of forming the L-type or D-type chiral metal oxide-based catalyst layer, the method may further include the step of depositing a single-atom catalyst on the chiral metal oxide-based catalyst layer. That is, a single-atom catalyst can be deposited on the metal oxide formed on the porous support using an electrodeposition method. For a description of the single-atom catalyst, refer to the previously described content. In one embodiment, the content of the single-atom catalyst may be 1 wt% to 10 wt%. Within the above-described range, the intrinsic properties of the electrode can be effectively realized while maintaining chirality when depositing the single-atom catalyst.

[0152] Next, an anion exchange membrane may be provided on one side of the first electrode (S300). The first electrode and the anion exchange membrane may be joined using a method for manufacturing a membrane electrode assembly through thermal compression. Alternatively, when assembling the anion exchange membrane water electrolysis device into a stack structure, the first electrode and the anion exchange membrane may be brought into contact with each other by pressure for assembly, specifically, for example, clamping pressure using a terminal plate described later without separate adhesive, but are not limited thereto.

[0153] The above anion exchange membrane may include one or more of quaternary ammonium, imidazolium, benzimidazole, polyimide, polystyrene, polylynorbornene, polyethylene, and triazolium based on a polymer backbone composed of poly(phenylene oxide), poly(ether ether ketone), poly(acryl ether sulfone), polybenzimidazole, polyimide, polystyrene, polylynorbornene, polyethylene, and polysiloxane.

[0154] Next, a second electrode may be provided on one side of the anion exchange membrane, spaced apart from the first electrode (S400). The second electrode may be joined using a method for manufacturing a membrane electrode assembly through thermal compression with the anion exchange membrane. Alternatively, when assembling the anion exchange membrane water electrolysis device into a stack structure, the second electrode and the anion exchange membrane may come into contact with each other by pressure for assembly, specifically, for example, clamping pressure using a terminal plate described later without separate adhesive, but are not limited thereto.

[0155] The second electrode may include an electrode catalyst and a support therefor. The support may include a carbon support such as carbon paper, porous carbon paper, carbon cloth, or porous carbon cloth, or a metal support such as a foam composed of Ni, Co, Fe, Ti, Ta, or an alloy thereof. The electrode catalyst may be applied differently depending on the type of the second electrode. For example, when the first electrode (100) is an anode and the second electrode (300) is a cathode, the electrode catalyst may be a hydrogen generation reaction catalyst, and specifically, may include one or more of a metal, alloy, or metal oxide including, for example, Pt, Ru, Ni, Co, Fe, or Mn. In this embodiment, a material in which a platinum-ruthenium alloy is deposited on carbon paper was used as the second electrode (300).

[0156] Next, an electrolyte can be filled into the first electrode, the anion exchange membrane, and the second electrode (S500). The electrolyte can be filled by connecting an external pipe inside the anion exchange membrane water electrolysis device after the first electrode, the anion exchange membrane, and the second electrode are provided. Alternatively, depending on the embodiment, the electrolyte may be filled immediately before or during the operation of the anion exchange membrane water electrolysis device. Specifically, for example, the electrolyte may include one or more of water, an aqueous potassium hydroxide solution (KOH(aq)), an aqueous sodium hydroxide solution (NaOH(aq)), and sodium sulfate (Na2SO4(aq)). The aqueous potassium hydroxide solution and the aqueous sodium hydroxide solution may have a concentration of 0.1 to 1 M.

[0157] Hereinafter, preferred experimental examples are presented to aid in understanding the present invention. However, the following experimental examples are intended only to aid in understanding the present invention, and the present invention is not limited by the following experimental examples.

[0158] Sample preparation

[0159] Cobalt chloride hexahydrate (CoCl2·6H2O, 98%), ferrous nitrate ahydrate (Fe(NO3)3·6H2O, 98%), nickel nitrate hexahydrate (Ni(NO3)2·6H2O, 98%), L-tartaric acid (99.5%), D-tartaric acid (99.0%), mesotartaric acid monohydrate (97.0%), and sodium carbonate (Na2CO3, 99.5%) were purchased from Sigma-Aldrich (USA). Potassium hydroxide (KOH, 85.0%) was purchased from Duksan Co., Ltd., Korea. PtRu / C (20wt% Ru, 40wt% Pt) was obtained from Alfa Aesar, USA. Nickel foam (Ni-foams) (thickness 1.6mm, 110ppi) was purchased from MTI Co., Ltd., USA. The nickel fiber porous transport layer (PTL) was purchased from Dioxide Materials, USA. The carbon paper PTL was purchased from SGL Carbon, Germany.

[0160] Measuring equipment and measurement methods

[0161] Absorption spectra were measured using a Jasco V-730 UV-Vis spectrophotometer. Circular dichroism (CD) measurements were performed using a Jasco J-1500 spectrophotometer with electrodeposited ITO glass in the beam path. CD spectra were recorded between wavelengths of 300–500 nm at a scanning speed of 100 nm / min. Magnetic conduction probe atomic force microscopy (mCP-AFM) measurements were performed using a Park Systems XE-70 equipped with an NSC-18 / Co-Cr tip (spring constant, ~2.8 N / m). For cantilever magnetization prior to measurement, the tip was magnetized in an upward or downward direction for at least 30 minutes using a permanent magnet of ~3500 Gauss. IV curve measurements were performed by sweeping voltages between -5 V and 5 V at different points at least 50 times. Work functions were measured using an AFM-based Kelvin probe force microscope (KPFM).

[0162] X-ray photoelectron spectroscopy (XPS) was performed using a Thermo Fisher Scientific Theta probe VASE system (USA). Scanning electron microscopy (SEM) and elemental mapping images were obtained using a ZEISS GeminiSEM 560 in conjunction with an SDD EDS system (Germany). Transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), and elemental mapping images were acquired using a dual SDD EDS system (Japan) and a 100 kV JEOL NEO ARM.

[0163]

[0164] Preparation Examples 1-1 to 1-11: Chiral cobalt-manganese oxide-based water electrolysis electrodes

[0165] The total amount of cobalt chloride hexahydrate (CoCl2-6H2O) and manganese chloride (MnCl2) was set to 0.16 mmol, and the addition ratio of cobalt chloride hexahydrate (CoCl2-6H2O) and manganese chloride (MnCl2) was adjusted so that the mixing ratio of cobalt and manganese was as shown in Table 1 below. After adding this mixture to 40 ml of ultrapure water, it was stirred for 10 minutes.

[0166] 1.6 mmol of L- and D-type tartaric acid (L- / D-tartaric acid) were each added to the above mixed solution and dissolved, then 4 mmol of sodium carbonate (Na2CO3) was added and stirred for 10 minutes. At this time, L- and D- represent chiral oxides.

[0167] With a clear solution prepared, a washed indium tin oxide (ITO) porous support is connected to the working electrode of a three-electrode system, a platinum (Pt) electrode is connected to the counter electrode, and a silver chloride (Ag / AgCl) electrode is connected to the reference electrode, with a constant current of 0.1 mA cm⁻¹. -2Water electrolysis electrodes were prepared by performing electrochemical deposition for 30 minutes, in which an L-type chiral metal oxide thin film and a D-type chiral metal oxide thin film were formed, respectively.

[0168] Classification Cobalt Manganese Preparation Example 1-11000 Preparation Example 1-2991 Preparation Example 1-3955 Preparation Example 1-49010 Preparation Example 1-58515 Preparation Example 1-68020 Preparation Example 1-77525 Preparation Example 1-86040 Preparation Example 1-94060 Preparation Example 1-102080 Preparation Example 1-110100

[0169]

[0170] Comparative Examples 1-1 and 1-2: Nickel-manganese oxide-based water electrolysis electrodes

[0171] A water electrolysis electrode having a meso-type metal oxide thin film was prepared by performing the same procedure as in Preparation Examples 1-1 and 1-4 above, except that a meso-type tartaric acid (L- / D- / Meso-tartaric acid) was used. Meso- refers to an oxide without chiral properties.

[0172]

[0173] FIGS. 4(a) and FIGS. 4(b) show the L- / D-CoO of Preparation Example 1-1 of the present invention. x and L- / D-MnO of Preparation Example 1-11 x This is an image showing the metal oxide thin film of the electrode.

[0174] Referring to FIGS. 4(a) and FIGS. 4(b), the L- / D-CoO of Preparation Example 1-1 x and L- / D-MnO of Preparation Example 1-11 x Through the electrode photographs, it can be confirmed that the colors of cobalt oxide and manganese oxide are brown.

[0175] FIG. 5 shows the L-Co of Preparation Examples 1-2 to 1-10 of the present invention. 1-y Mn y O x (y = 0.01, 0.05, 0.1, 0.15, 0.2, 0.25, 0.4, 0.6 and 0.8) This is an image showing the metal oxide thin film of the electrode.

[0176] Referring to FIG. 5, the L-Co of Preparation Examples 1-2 to 1-10 1-y Mn y O x (y = 0.01, 0.05, 0.1, 0.15, 0.2, 0.25, 0.4, 0.6 and 0.8) Through the electrode photographs, it can be seen that as the manganese doping content in the cobalt increases, a change to a gradually dark brown color occurs.

[0177] FIGS. 6(a) to 6(c) are images showing the results of contact angle analysis for the electrodes of Preparation Example 1-1 (Co 100%), Preparation Example 1-4 (Co 90% + Mn 10%), and Preparation Example 1-11 (Mn 100%) of the present invention. Specifically, the moment a drop of water was dropped onto the chiral metal oxide thin film of the electrodes of Preparation Example 1-1, Preparation Example 1-4, and Preparation Example 1-11 was photographed, and the contact angle was measured. The scale bar is 1 μm. The average angle, left angle, right angle, drop volume, and temperature of the contact angle are shown together in the figure.

[0178] Figures 6(a) to 6(c) show the extent to which surface roughness affects hydrophilicity according to the cobalt-manganese content. Specifically, it can be seen that the electrode of Preparation Example 1-1 (Co 100%) in Figure 6(a) and the electrode of Preparation Example 1-11 (Mn 100%) in Figure 6(c) exhibit very low contact angles due to their strong hydrophilicity and ability to adsorb water well. On the other hand, in the electrode of Preparation Example 1-4 (Co 90% + Mn 10%) in Figure 6(b), when cobalt and manganese are mixed, it can be seen that the contact angle becomes very high while relatively low hydrophilicity is exhibited due to the difference in surface roughness. Additionally, it can be seen that a uniform surface is formed in the electrode of Preparation Example 1-4 (Co 90% + Mn 10%) in Figure 6(b) as 10 to 20% of manganese is doped into the cobalt.

[0179] FIG. 7 is an image of the thin film shape of the electrodes of Preparation Examples 1-1 to 1-11 of the present invention and the control group (nickel foam) observed using a scanning electron microscope (SEM).

[0180] Referring to FIG. 7, it can be seen that the surface roughness differs as the amount of manganese gradually increases, as in Preparation Examples 1-2 to 10, compared to the 100% cobalt of Preparation Example 1-1. Additionally, it can be seen that a rough surface appears when the manganese content is low, as in the electrodes of Preparation Example 1-2 and Preparation Example 1-3, but a uniform surface is exhibited when the manganese doping content is 10 to 20%, as in the electrodes of Preparation Examples 1-4 to 1-6. Furthermore, it can be seen that as the manganese content increases further, as in Preparation Examples 1-7 to 1-11, spherical particles are formed, resulting in an uneven electrode surface.

[0181] In metal oxides, the diffusion rate varies depending on the bond strength of metal-oxygen (metal-O), and the higher the bond strength, the lower the diffusion rate may be. The bond energy of manganese-oxygen (Mn-O) is 402 kJ / mol, while the bond energy of cobalt-oxygen (Co-O) is 368 kJ / mol, indicating that the bond energy of manganese-oxygen is higher. As mobility decreases due to manganese doping, the degree of particle aggregation caused by collisions is reduced, allowing for the formation of a uniform thin film of small particles. Consequently, roughness can be reduced up to a certain level depending on the manganese doping content.

[0182] FIG. 8(a) is a graph showing the electrodes of Preparation Examples 1-1 to 1-11 of the present invention analyzed by linear scanning potential (LSV), and FIG. 8(b) is a graph showing the correlation between the contact angle and the overpotential required for the oxygen evolution reaction (OER) according to the manganese dopant (Mn dopant) ratio of the electrodes of Preparation Examples 1-1 to 1-11 of the present invention.

[0183] FIG. 8(a) shows the electrodes of Preparation Examples 1-1 to 1-11 at a length of 1 cm 2 After cutting the electrode into an area and placing it in a 1M KOH solution, the working electrode was connected, the platinum electrode was connected to the counter electrode, and the silver chloride electrode (Ag / AgCl) was connected to the reference electrode. A portion of the electrodes was immersed in 40ml of a 1M KOH solution, and the measurement range was set from 1.2V to 2.0V (V Vs. RHE) in linear scanning potential (LSV) mode and measurements were taken.

[0184] Specifically, OH radicals, which are intermediate products of the oxygen evolution reaction (OER), are slow reactions that determine the reaction rate and are relatively hydrophobic, repelling water from the surroundings and reducing the total charge required for the reaction. However, if the surface is partially made hydrophobic, this process is omitted, and a state is created where OH radicals can be generated immediately, allowing for a rapid reaction and lowering the overpotential. Accordingly, the efficiency of the electrode can be confirmed by comparing the current density at the same voltage in the results measured by the linear scanning potential (LSV) method, which is data measuring current density according to voltage as shown in Fig. 8(a).

[0185] Referring to FIG. 8(a), the electrode of Preparation Example 1-4 (L-Co) in which 10% manganese is doped into cobalt 0.9 Mn 0.1 O x It can be seen that it exhibits the lowest overpotential in ). In addition, Preparation Example 1-7 (L-Co 0.75 Mn 0.25 O x ) and, Preparation Example 1-8 (L-Co 0.6 Mn 0.4 O x ) and, Preparation Example 1-10 (L-Co 0.2 Mn 0.8 O x ) is Preparation Example 1-6 (L-Co 0.8 Mn 0.2 O x It appeared as a value similar to ).

[0186] Figure 8(b) shows the relationship between the contact angle and the overpotential, and it can be seen that when the manganese doping ratio in Preparation Example 1-4 is 10%, the highest contact angle and the lowest overpotential are observed. As shown in the following equation (9), as manganese is doped into a hydrophilic surface, the surface roughness decreases, and the surface becomes hydrophobic. When the manganese doping ratio is 1 to 5%, the surface roughness is non-uniform, so the contact angle increases slightly, whereas when it is 10%, the surface is very uniform, so the roughness decreases and the contact angle is formed highest, and from 10% or more, the roughness increases due to the formation of large particles, so the contact angle may decrease again.

[0187] … … Equation (9)

[0188] In the above equation (9), θ real : Actual observed contact angle, θ ideal : It is the contact angle measured on a physically smooth surface.

[0189] Since the surface of Preparation Example 1-4 in Fig. 7 described above is uniform, it can be considered that the roughness has decreased. In addition, it is determined that the contact angle has increased due to the decrease in hydrophilicity. When hydrophilicity decreases, OH during the oxygen evolution reaction (OER) - During the reaction from ions to ·OH radicals, the ·OH radicals are relatively hydrophobic, so the overpotential can be reduced through the effect of lowering the reaction energy.

[0190] FIGS. 9(a) to 9(c) show the L- / D-CoO of Preparation Example 1-1 of the present invention. x Electrode, L- / D-Co of Preparation Example 1-4 0.9 Mn 0.1 O x Electrode and L- / D-MnO of Preparation Example 11 xThis is a graph showing the circular dichroism (CD) and ultraviolet-visible (UV-Vis) spectrophotometric measurement data of the electrodes. After placing the electrodes in the circular dichroism apparatus, measurements were taken after setting the measurement range to 300 to 500 nm. Chiral characteristics were measured by irradiating two different lights, left circular polarization and right circular polarization, and measuring the CD as the difference in absorption for one of the lights.

[0191] In the left graphs of Figures 9(a) to 9(c), when aligned in one direction, a skewed graph can be observed.

[0192]

[0193] The right graphs of Figures 9(a) to 9(c) are typical absorption wavelengths, and the thickness of the thin film can be determined according to the degree of absorption.

[0194] … … Equation (10)

[0195] According to the CD values ​​of FIGS. 9(a) to 9(c) and the g-factor calculation formula of Equation (10), the L-CoO of Preparation Example 1-1 x The g-factor is 8.95 x 10⁻⁶ -5 and, D-CoO x The g-factor is 6.79 x 10⁻⁶ -5 is. In addition, the L-Co of Preparation Examples 1-4 0.9 Mn 0.1 O x The g-factor of is 1.29 x 10⁻⁶ -4 is, and D-Co 0.9 Mn 0.1 O x The g-factor of is 1.47 x 10 -4 am.

[0196] FIG. 10 is Preparation Example 1-1 of the present invention (L- / D-CoO x ) Electrode and Preparation Example 1-4 (L- / D-Co 0.9 Mn 0.1 O x This is a graph showing the g-factor of the electrodes compared.

[0197] Referring to FIG. 10, the atomic radius of manganese is 161 pm, and the atomic radius of cobalt is 152 pm, so the atomic radius of manganese is larger. Accordingly, the distortion of the electrode of Preparation Example 1-4 increased as manganese was doped into cobalt. The electrode of Preparation Example 1-1 (CoO x The electrode of Preparation Example 1-4 (Co) is better than ) 1-y Mn y O x The increase in the distortion of ) can be confirmed through the g-factor. As such, spin selectivity and oxygen evolution reaction (OER) efficiency can be increased through the enhancement of chirality by manganese.

[0198] FIG. 11 is a graph showing the ratio of cobalt ions to manganese ions according to the manganese doping content of the electrodes of Preparation Example 1-3 (Mn 5), Preparation Example 1-4 (Mn 10), Preparation Example 1-5 (Mn 15), Preparation Example 1-6 (Mn 20), and Preparation Example 1-7 (Mn 25) of the present invention.

[0199] Referring to Fig. 11, manganese is Mn 2+ , Mn 3+ , and Mn 4+ It is a representative material of the Jahn-Teller effect, which twists the structure of substances with various oxidation states. Among them, Mn 3+ is (t 2g 3 e g 1 The orbital of ), Mn 4+ is (t 2g 3 e g 0 It has an orbital of ) so Mn 3+ Distortion increases due to the antibonding of ions, and Mn 4+ ...can reduce distortion. When the manganese doping ratio in the electrode of Preparation Example 1-4 of the present invention is 10%, as the electron withdrawing effect increases, Co on the XPS analysis result of Fig. 11 3+ / Co 2+ The ratio of is high, and Mn 4+ / Mn 3+ Since the ratio of decreases, Mn 3+ It can be seen that the distortion increases with the increase in ions. This is consistent with the g-factor results in Fig. 9 described above, and through this, the oxygen evolution reaction (OER) efficiency can also be increased.

[0200] FIG. 12(a) is a schematic diagram of a measurement method using a magnetic conductive probe atomic force microscopy (mCP-AFM) according to an embodiment of the present invention, and FIG. 12(b) and FIG. 12(c) are of the L- / D-CoO of Preparation Example 1-1 of the present invention. x and L- / D-Co of Preparation Examples 1-4 0.9 Mn 0.1 O x This is a graph showing the chiral-induced spin selectivity of the electrode.

[0201] As shown in Fig. 12(a), electrical characteristics were analyzed using a magnetic conductive probe atomic force microscope (mCP-AFM). Depending on the chiral direction, a centripetal force acts on the Lorentz force, causing electrons to rotate in a specific direction and forming a magnetic field. Consequently, when electrons with an up or down spin pass through, only those electrons that match the magnetic field in one direction formed by the chirals pass through, while electrons with the opposite spin are prevented from passing through, thus acting as a spin filter.

[0202] In FIG. 12(a), the Co-Cr tip is a tip capable of exhibiting magnetism, and the tip is magnetized according to the N or S pole of a permanent magnet. When this is brought into contact with a chiral thin film and current flows, if electrons transmitted through the magnetized Co-Cr tip flow in a direction consistent with the chiral direction, the signal is amplified, and if the opposite is true, the signal is weakened. Accordingly, the electrodes of Preparation Example 1-1 and Preparation Example 1-4 of the present invention were positioned in the center of the scanning probe microscope in the left image of FIG. 12, and currents from -5V to 5V were measured using the magnetized ferromagnetic tip.

[0203] Referring to the measurement result in Fig. 12(b), it can be seen that the trends of the current flow in L- and D- are opposite when up and when down, which confirms the chiral characteristics as a phenomenon where the signal is amplified or weakened depending on the N or S pole. The same measurement result can be confirmed when manganese is doped in Fig. 12(c).

[0204]

[0205] Preparation Examples 1-12 and 1-13: Chiral metal oxide-based water electrolysis electrodes deposited on nickel foam

[0206] Water electrolysis electrodes were prepared by performing the same procedure as in Preparation Examples 1-1 and 1-4 above, except that nickel foam (Ni foam) was used as the porous support, thereby forming L-type chiral metal oxide thin films and D-type chiral metal oxide thin films, respectively.

[0207] Comparative Examples 1-3 and 1-4: Metal oxide-based water electrolysis electrodes deposited on nickel foam

[0208] A water electrolysis electrode having a meso-type metal oxide thin film formed thereon was prepared by performing the same procedure as in Comparative Examples 1-1 and 1-2 above, except that nickel foam (Ni foam) was used as the porous support.

[0209] FIGS. 13(a) and FIGS. 13(b) show the L- / D-CoO of Preparation Example 1-12 of the present invention. x Electrode, Meso-CoO of Comparative Examples 1-3 x Electrode, L- / D-Co of Preparation Example 1-13 0.9 Mn 0.1 O x Electrode and Meso-Co of Comparative Examples 1-4 0.9 Mn 0.1 O x This graph shows the results of analyzing the extent of hydrogen peroxide generation via UV-Vis depending on the presence or absence of spin after the oxygen evolution reaction (OER) at the electrode. Through this, the results of hydrogen peroxide generation according to reaction time in cobalt and cobalt-manganese oxides can be confirmed.

[0210] Specifically, for analysis, the L- / D-CoO of Preparation Example 1-12 x Electrode, Meso-CoO of Comparative Examples 1-3 x Electrode, L- / D-Co of Preparation Example 1-13 0.9 Mn 0.1 O x Electrode and Meso-Co of Comparative Examples 1-4 0.9 Mn 0.1 O x The electrode was connected to the working electrode, the platinum electrode to the counter electrode, and the silver chloride electrode to the reference electrode. These were immersed in 40 ml of 0.1 M Na2SO4 solution, and 1 ml of the reaction solution was extracted at 30-minute intervals. The solution was then mixed with a 0.1% w / v aqueous ortho-tolidine solution in a 5:1 ratio and analyzed using a UV-Vis spectrophotometer. When the electrode was reacted in a 0.1 M Na2SO4 electrolyte for 180 minutes, the reaction with the electrode resulted in the generation of hydrogen peroxide. When mixed with the ortho-tolidine indicator (0.1% w / v in 1 M HCl), the solution turned yellow, and the absorbance of hydrogen peroxide could be confirmed by measuring the absorbance of the solution.

[0211] Referring to FIGS. 13(a) and FIGS. 13(b), the L- / D-CoO of Preparation Example 1-12 x Electrode and L- / D-Co of Preparation Example 1-130.9 Mn 0.1 O x In cases where chiral properties are present, such as with electrodes, almost no hydrogen peroxide is generated, whereas Comparative Examples 1-3 and Meso-CoO x Electrode or Meso-Co of Comparative Examples 1-4 0.9 Mn 0.1 O x In cases where chiral properties are absent, such as with electrodes, the presence or absence of chiral properties can be confirmed through the generation of hydrogen peroxide.

[0212] Preparation Examples 1-14 to 1-16: Chiral nickel-manganese oxide-based water electrolysis electrodes

[0213]

[0214] The total amount of nickel chloride hexahydrate (NiCl2-6H2O) and manganese chloride (MnCl2) was 0.16 mmol, and the addition ratio of nickel chloride hexahydrate (NiCl2-6H2O) and manganese chloride (MnCl2) was adjusted so that the mixing ratio of nickel and manganese was as shown in Table 2 below. After adding this mixture to 40 ml of ultrapure water, it was stirred for 10 minutes.

[0215] 1.6 mmol of L-type and D-type tartaric acid were added to the above mixed solution and dissolved, then 4 mmol of sodium carbonate (Na2CO3) was added and stirred for 10 minutes.

[0216] With a clear solution prepared, the washed indium tin oxide porous support is connected to the working electrode of a three-electrode system, a platinum electrode is connected to the counter electrode, and a silver chloride (Ag / AgCl) electrode is connected to the reference electrode to a constant current of 0.1 mA cm⁻¹ -2 Water electrolysis electrodes were prepared by performing electrochemical deposition for 30 minutes, in which an L-type chiral metal oxide thin film and a D-type chiral metal oxide thin film were formed, respectively.

[0217] Classification Nickel Manganese Preparation Example 1-14 1000 Preparation Example 1-15 9010 Preparation Example 1-16 8020

[0218] Preparation Examples 1-17 to 1-20: Chiral nickel-cobalt oxide-based water electrolysis electrodes nickel chloride hexahydrate (NiCl2-6H2O) and cobalt chloride hexahydrate (CoCl 2- To ensure the total amount of 6H2O is 0.16 mmol, and to ensure the mixing ratio of nickel and cobalt is as shown in Table 3 below, nickel chloride hexahydrate (NiCl2-6H2O) and cobalt chloride hexahydrate (CoCl2-6H2O) are prepared. 2- The addition ratio of 6H2O was adjusted and added to 40 ml of ultrapure water, then stirred for 10 minutes.

[0219] 1.6 mmol of L-type and D-type tartaric acid were added to the above mixed solution and dissolved, respectively, then 4 mmol of sodium carbonate (Na2CO3) was added and stirred for 10 minutes.

[0220] With a clear solution prepared, the washed indium tin oxide porous support is connected to the working electrode of a three-electrode system, a platinum (Pt) electrode is connected to the counter electrode, and a silver chloride (Ag / AgCl) electrode is connected to the reference electrode to achieve a constant current of 0.1 mAcm -2 Water electrolysis electrodes were prepared by performing electrochemical deposition for 30 minutes, in which an L-type chiral metal oxide thin film and a D-type chiral metal oxide thin film were formed, respectively.

[0221] Classification Nickel Cobalt Manufacturing Example 1-17 90 10 Manufacturing Example 1-18 80 20 Manufacturing Example 1-19 20 80 Manufacturing Example 1-20 10 90

[0222] FIGS. 14(a) to 14(c) show the L-NiO of Preparation Examples 1-14 to 1-20 of the present invention. x , L-Ni 0.9 Mn 0.1 O x , L-Ni 0.8 Mn 0.2 O x , L-Ni 0.9 Co 0.1 O x , L-Ni 0.8 Co 0.2 O x , L-Co0.9 Ni 0.1 O x , L-Co 0.8 Ni 0.2 O x This is a graph showing the results of analyzing the electrodes using linear scanning potentiometry (LSV). For the analysis, the electrodes of Preparation Examples 1-14 to 1-20 of the present invention were 1 cm 2 After cutting the electrodes into an area and placing them in a 1M KOH solution, the working electrode was connected to the platinum electrode, the silver chloride electrode (Ag / AgCl) was connected to the reference electrode, and a portion of the electrodes was immersed in 40ml of a 1M KOH solution. Measurements were then taken using linear scanning potentiometry (LSV) mode with the measurement range set from 1.2V to 2.0V (vs. RHE). Nickel foam (Ni foam) was measured as a control. As shown in Figures 14(a) to 14(c), chiral metal oxide thin films can be easily deposited by doping with heterogeneous elements, thereby allowing verification of the difference in electrode efficiency according to the doping content.

[0223]

[0224] Specifically, as a result of measuring the oxygen evolution reaction (OER) of electrodes doped with 10% and 20% manganese relative to chiral nickel oxide in Fig. 14(a), the current density measured at 1.8 V was 130.84 mA cm⁻¹. -2 At 131.8 mA cm -2 and 147.27 mA cm -2 It was improved, and as the overvoltage decreased from 338 mV to 290 mV and 287 mV, it can be confirmed that the efficiency has increased further.

[0225] In Fig. 14(b), the oxygen evolution reaction (OER) of electrodes doped with 10% and 20% cobalt relative to chiral nickel oxide was measured, and the current density measured at 1.8 V was 130.84 mA cm⁻¹. -2 At 161.87 mA cm -2 and 191.94 mA cm -2It was improved, and as the overvoltage decreased from 338 mV to 334 mV and 332 mV, it can be confirmed that the efficiency has increased further.

[0226] In Fig. 14(c), the oxygen evolution reaction (OER) of electrodes doped with 80% and 90% cobalt relative to chiral nickel oxide was measured, and the current density measured at 1.8 V was 130.84 mA cm⁻¹. -2 At 210.02 mA cm -2 and 201.43 mA cm -2 It was improved, and it can be confirmed that the efficiency has increased further as the overvoltage decreased from 338 mV to 297 mV and 302 mV.

[0227] Preparation Example 1-21: Chiral iridium oxide-based water electrolysis electrode

[0228] A solution prepared by dissolving 1.6 mmol of L-, D-, and Meso-form tartaric acids and 32 mmol of sodium carbonate (Na2CO3) in 0.16 mmol of iridium chloride trihydrate (IrCl3-3H2O) in 40 ml of distilled water was applied to indium tin oxide (ITO) at 1.0 mA cm⁻¹. -2 An iridium oxide water electrolysis electrode was prepared by performing electrodeposition for 30 minutes.

[0229] FIG. 15 is the L-IrO of Preparation Example 1-21 of the present invention. x and D-IrO x This is an image of the metal oxide thin film of the electrode.

[0230] Referring to Fig. 15, L-IrO using iridium metal x It was electrodeposited, and it can be confirmed that it is blue, which is the color of iridium oxide.

[0231]

[0232] Preparation Example 1-22: Chiral iridium oxide-based water electrolysis electrode

[0233] A solution prepared by dissolving 1.6 mmol of L-, D-, and Meso-form tartaric acids and 32 mmol of sodium carbonate (Na2CO3) in 0.16 mmol of iridium chloride trihydrate (IrCl3-3H2O) in 40 ml of distilled water was applied to nickel foam (Ni foam) at 1.0 mA cm⁻¹ -2 An iridium oxide water electrolysis electrode was prepared by performing electrodeposition for 30 minutes.

[0234] FIG. 16(a) is a nickel foam image, FIG. 16(b) is the L-IrO of Preparation Example 1-22 of the present invention. x and D-IrO x This is an image showing the electrode.

[0235] Figure 16(a) shows a nickel foam electrode used for oxygen evolution (OER), and as shown in Figure 16(b), it can be seen that chiral iridium oxide is well deposited on the nickel foam electrode.

[0236] FIG. 17 shows the L-IrO of Preparation Example 1-22 of the present invention. x and D-IrO x This is a graph showing the results of analyzing the electrode and control group (nickel foam) using linear scanning potentiometry (LSV). The electrode of Preparation Example 1-22 is 1 cm 2 After cutting the electrode into an area and placing it in a 1M KOH solution, the working electrode was connected, the platinum electrode was connected to the counter electrode, and the silver chloride electrode (Ag / AgCl) was connected to the reference electrode. A portion of the electrodes was immersed in 40ml of a 1M KOH solution, and measurements were taken using linear scanning potentiometry (LSV) mode with the measurement range set from 1.2V to 2.0V (vs. RHE). Nickel foam (Ni foam) was also measured as a control.

[0237] Referring to FIG. 17, the current density measured at 1.8 V for the electrode of Preparation Example 1-22 with deposited chiral L- and D-iridium oxide and the nickel foam control without deposited chiral iridium oxide is 27.47 mA cm⁻¹. -2 L-iridium oxide at 352.88 mA cm⁻¹ -2 and D-iridium oxide 303.36 mA cm-2 It was improved, and it can be confirmed that the efficiency increased further as the overvoltage decreased from 484 mV to 142 mV for L-iridium oxide and 181 mV for D-iridium oxide.

[0238] Preparation Example 2-1: Chiral metal oxide-based water electrolysis electrode equipped with Ir monatomic catalyst

[0239] A solution of 100 µM iridium chloride trihydrate (IrCl3-3H2O) dissolved in a 1 M aqueous potassium hydroxide (KOH) solution was used with the L- / D-CoO prepared in Preparation Example 1-1 above. x Water electrolysis electrodes were prepared by performing 10 cycles of electrochemical deposition in -0.4V to 0.1V (vs. Standard hydrogen electrode, SHE) cyclic voltammetry mode on an anion exchange membrane water electrolysis device, thereby forming L-type chiral metal oxide thin films and D-type chiral metal oxide thin films equipped with an Ir single-atom catalyst, respectively.

[0240] Preparation Example 2-2: Chiral metal oxide-based anion exchange membrane water electrolysis electrode equipped with Ru monatomic catalyst

[0241] Water electrolysis electrodes were prepared by performing the same procedure as in Preparation Example 2-1 above, except that ruthenium chloride trihydrate (RuCl3-3H2O) was used instead of iridium chloride trihydrate (IrCl3-3H2O), thereby forming L-type chiral metal oxide thin films and D-type chiral metal oxide thin films equipped with Ru monatom catalysts.

[0242] Preparation Example 2-3: Chiral metal oxide-based anion exchange membrane water electrolysis electrode equipped with a Pt monatomic catalyst

[0243] Water electrolysis electrodes were prepared by performing the same procedure as in Preparation Example 2-1 above, except that platinum chloride (PtCl2) was used instead of iridium chloride trihydrate (IrCl3-3H2O), thereby forming L-type chiral metal oxide thin films and D-type chiral metal oxide thin films equipped with a Pt monatomic catalyst.

[0244] Preparation Example 2-4: Chiral metal oxide-based anion exchange membrane water electrolysis electrode equipped with an Ag monatomic catalyst

[0245] Water electrolysis electrodes were prepared by performing the same procedure as in Preparation Example 2-1 above, except that silver chloride (AgCl) was used instead of iridium chloride trihydrate (IrCl3-3H2O), and L-type chiral metal oxide thin films and D-type chiral metal oxide thin films equipped with an Ag single-atom catalyst were formed, respectively.

[0246] Preparation Example 2-5: Chiral metal oxide-based anion exchange membrane water electrolysis electrode equipped with a Cu monatomic catalyst

[0247] In the above Preparation Example 2-1, copper chloride dihydrate (CuCl₂) instead of iridium chloride trihydrate (IrCl₃-3H₂O) 2- Water electrolysis electrodes were prepared by performing the same procedure except that 2H2O) was used, in which an L-type chiral metal oxide thin film and a D-type chiral metal oxide thin film equipped with a Cu single-atom catalyst were formed, respectively.

[0248] Preparation Example 2-6: Chiral metal oxide-based anion exchange membrane water electrolysis electrode equipped with Fe monatomic catalyst

[0249] Water electrolysis electrodes were prepared by performing the same procedure as in Preparation Example 2-1 above, except that iron chloride hexahydrate (FeCl3-6H2O) was used instead of iridium chloride trihydrate (IrCl3-3H2O), thereby forming L-type chiral metal oxide thin films and D-type chiral metal oxide thin films equipped with Fe monoatom catalysts.

[0250]

[0251] FIG. 18 is a graph showing the electrode of Preparation Example 2-1 of the present invention analyzed by linear scanning potential (LSV). Specifically, the electrode of Preparation Example 2-1 is 1 cm 2After cutting the electrodes into sections and placing them in a 1M KOH solution, the working electrode was connected to the platinum electrode, the counter electrode to the silver chloride electrode (Ag / AgCl) to the reference electrode. A portion of the electrodes was immersed in 40ml of a 1M KOH solution, and measurements were taken using linear scanning potentiometry (LSV) mode with the measurement range set from 1.2V to 2.0V (vs. RHE). Nickel foam (Ni foam) was also measured as a control.

[0252] L-CoO via Fig. 18 x It can be confirmed that single-atom catalysts or heterogeneous or multi-atom catalysts can be easily deposited by additionally electrodepositing iridium (Ir) after deposition. Furthermore, as shown in Fig. 18, the oxygen evolution reaction (OER) of the electrode deposited with an iridium single-atom catalyst compared to chiral cobalt oxide was measured, and the current density measured at 1.8 V was 178.04 -2 At 221.54 mA cm -2 It was improved, and as the overvoltage decreased from 350 mV to 287 mV, it can be confirmed that the efficiency has increased further.

[0253]

[0254] Preparation Example 2-7: Chiral metal oxide-based anion exchange membrane water electrolysis electrode equipped with an Ir monatomic catalyst

[0255] In the above Preparation Example 2-1, the L-Co of Preparation Example 1-4, not Preparation Example 1-1. 0.9 Mn 0.1 O x A water electrolysis electrode was prepared by performing the same procedure except for using Ir single-atom catalyst, thereby forming an L-type chiral metal oxide thin film.

[0256] Preparation Example 2-8: Chiral metal oxide-based anion exchange membrane water electrolysis electrode equipped with an Ir monatomic catalyst

[0257] In the above Preparation Example 2-1, the L-Co of Preparation Example 1-5, not Preparation Example 1-1. 0.85 Mn 0.15 O xA water electrolysis electrode was prepared by performing the same procedure except for using Ir single-atom catalyst, thereby forming an L-type chiral metal oxide thin film.

[0258] FIG. 19(a) shows the thin film shape of Preparation Example 2-7 of the present invention, and FIG. 19(b) is a graph showing the linear scanning potentiometry (LSV) analysis of the electrodes of Preparation Examples 1-4, 1-5, 2-7, 2-8, and the control group (nickel foam) of the present invention. Specifically, the electrodes of Preparation Examples 1-4, 1-5, 2-7, 2-8, and the control group (nickel foam) are 1 cm 2 After cutting the area to a specific size and placing it in a 1M KOH solution, it was connected to the working electrode, the platinum electrode was connected to the counter electrode, and the silver chloride electrode (Ag / AgCl) was connected to the reference electrode. It was then immersed in 40ml of a 1M KOH solution, and the measurement range was set from 1.2V to 2.0V (vs. RHE) in linear scanning potential (LSV) mode.

[0259] Referring to FIG. 19(b), in Preparation Examples 2-7 and 2-8, Ir is L-Co 1-y Mn y O x By forming an L-type chiral metal oxide thin film equipped with an Ir single-atom catalyst by electrodeposition at (y = 0.1 and 0.15), it can be seen that the efficiency of the electrode increased further, as the overpotential decreased from 310 mV to 249 mV at y=0.1 and from 309 mV to 263 mV at y=0.15.

[0260] Preparation Example 3-1: Chiral metal oxide-based water electrolysis electrode formed by electrodeposition

[0261] The total amount of cobalt chloride hexahydrate (CoCl2-6H2O) was made to 0.16 mmol, added to 40 ml of ultrapure water, and stirred for 10 minutes. 1.6 mmol of L-type tartaric acid was added to each of the above mixed solutions and dissolved, then 4 mmol of sodium carbonate (Na2CO3) was added and stirred for 10 minutes.

[0262] Fluorine-doped tin oxide (FTO) glass substrate (area = 10,000 mm²) washed in a clear mixed solution 2 Connect ) to the working electrode of the 3-electrode system, connect a platinum (Pt) electrode to the counter electrode, and connect a silver chloride (Ag / AgCl) electrode to the reference electrode to a constant current of 0.1 mA cm⁻¹ -2 An L-type chiral metal oxide thin film was prepared as a water electrolysis electrode by performing electrochemical deposition for 30 minutes. This was denoted as L-SPL.

[0263] Preparation Example 3-2: Chiral metal oxide-based water electrolysis electrode formed by electrodeposition

[0264] In the above Preparation Example 3-1, the area of ​​the chiral metal oxide thin film is 2500 mm 2 Except for the part formed as, it was performed identically.

[0265] Comparative Example 3-1: Chiral metal oxide-based water electrolysis electrode formed by spray coating

[0266] 0.2 mmol of cobalt chloride hexahydrate (CoCl2-6H2O), 0.2 mmol of L-tartaric acid, 0.25 mmol of sodium borohydride (NaBH4), 0.25 mmol of sodium citrate (Na3CH5O7), and 23 ml of deionized water were mixed. The precipitate formed during mixing was washed to form L-Co3O4 nanoparticles. The nanoparticles were dispersed in isopropyl alcohol (IPA) (10 wt%) and then spray-coated onto the fluorine-doped tin oxide to prepare an L-type chiral metal oxide thin film as a water electrolysis electrode. This was denoted as L-Co3O4.

[0267] Comparative Example 3-2: Chiral metal oxide-based water electrolysis electrode formed by spray coating

[0268] In the above Comparative Example 3-1, the area of ​​the chiral metal oxide thin film is 2500 mm 2Except for the part formed as, it was performed identically.

[0269]

[0270] Preparation Example 4-1: Chiral metal oxide-based anion exchange membrane water electrolysis device

[0271] Anode preparation: A nickel fiberboard was prepared as a porous transport layer to function as a porous transport layer (PTL). The total amount of cobalt chloride hexahydrate (CoCl2-6H2O) and manganese chloride (MnCl2) was set to 0.16 mmol, and the addition ratio of cobalt chloride hexahydrate (CoCl2-6H2O) and manganese chloride (MnCl2) was adjusted so that the mixing ratio of cobalt and manganese was as shown in Preparation Example 1-1 of Table 1 below (cobalt 100: manganese 0). After adding this mixture to 40 ml of ultrapure water, the mixture was stirred for 10 minutes.

[0272] 1.6 mmol of L-type tartaric acid was added to the above mixed solution and dissolved, then 4 mmol of sodium carbonate (Na2CO3) was added and stirred for 10 minutes.

[0273] With the above-prepared nickel fiber plate immersed in the above-mentioned mixed solution, it is connected to the working electrode of the 3-electrode system, a platinum (Pt) electrode is connected to the counter electrode, and a silver chloride (Ag / AgCl) electrode is connected to the reference electrode at room temperature (0.3 mg / cm²). -2 0.272 mA cm for 30 minutes in ) -2 L-CoO by performing electrochemical deposition under the conditions x An electrode composed of -PTL was formed. The formed electrode was washed with deionized water and dried under vacuum conditions to produce an anode electrode with an area of ​​10mm x 10mm.

[0274] Cathode Preparation: A cathode catalyst slurry was prepared by mixing platinum-ruthenium (PtRu) nanoparticles with an ionomer, isopropyl alcohol, and deionized water, and ultrasonically treating the mixture at 5°C for 1 hour. Carbon paper was used as the cathode PTL. The cathode catalyst loading amount on the carbon paper was 0.7 mg cm⁻¹. -2 A cathode was manufactured by spray-coating the above slurry to achieve this.

[0275] Preparation of anion exchange membrane: A poly(aryl-co-aryl piperidinium) (PDTP-25) membrane with a thickness of approximately 30 μm was used as the anion exchange membrane (AEM). Before the test, the AEM was immersed in a 1 M KOH solution at 60°C for 3 hours, and the solution was replaced with a fresh solution every hour.

[0276] The effective area is 5cm 2 As shown in FIG. 1, the assembly was configured to further include a PTFE gasket, a separator, a current collector, and an end plate. For the separator, a gold-coated nickel plate was used on the anode side, and a graphite plate was used on the cathode side.

[0277] Preparation Example 4-2: Chiral metal oxide-based anion exchange membrane water electrolysis device

[0278] In the above Preparation Example 4-1, the mixing ratio of cobalt and manganese as the anode electrode is set to be as in Preparation Example 1-4 of Table 1 (cobalt 90: manganese 10), and L-Co 0.9 Mn 0.1 O x The procedure was performed identically, except that an electrode composed of -PTL was formed. In some drawings, the above L-Co 0.9 Mn 0.1 O x -PTL is L-Mn 0.1 -Co 0.9 O x It may be denoted as -PTL, but it is the same material.

[0279] Preparation Example 4-3: Chiral metal oxide-based anion exchange membrane water electrolysis device

[0280] The above Manufacturing Example 4-1 was performed in the same manner, except that the anode electrode area was formed to be 30mm x 30mm.

[0281] Preparation Example 4-4: Chiral metal oxide-based anion exchange membrane water electrolysis device

[0282] The above Manufacturing Example 4-1 was performed in the same manner, except that the anode electrode area was formed to be 50mm x 50mm.

[0283] Comparative Example 4-1: Nickel Foam Preparation

[0284] As a control group, the nickel fiber board used in Preparation Example 4-1 above was prepared.

[0285] Preparation Example 5-1: Chiral nickel-iron oxide-based anion exchange membrane water electrolysis device

[0286] In the preparation of the anode in Preparation Example 4-1 above, 2 mmol of Fe(NO3)3·9H2O and 1 mmol of Ni(NO3)2·6H2O were mixed and prepared, and 3 mmol of L-tartaric acid and 3 mmol of D-tartaric acid were added to each of the mixtures. The mixtures were dissolved in 50 ml of methanol and 2.5 ml of deionized water and stirred for 30 minutes to prepare a mixed solution.

[0287] A nickel fiber plate prepared with PTL is immersed in the above mixed solution and connected to the working electrode of a 3-electrode system, a platinum electrode is connected to the counter electrode, and a silver chloride (Ag / AgCl) electrode is connected to the reference electrode, and at room temperature (0.3 mg cm⁻¹) -2 A nickel iron oxide catalyst layer was formed on the substrate using chronoamperometry (CA) mode at a voltage of -1.3V for 30 minutes. The remaining process was carried out in the same manner, except that the formed electrode was washed with ethanol and dried under vacuum conditions.

[0288] Comparative Example 5-1: Achiral nickel-iron oxide-based anion exchange membrane water electrolysis device

[0289] The procedure was carried out in the same manner as in Preparation Example 5-1 above, except that meso-tartaric acid was used instead of L-tartaric acid or D-tartaric acid.

[0290] Measurement method of anion exchange membrane water electrolysis device

[0291] The above-mentioned anion exchange membrane water electrolysis (AEMWE) was evaluated using a single-cell test. Performance was measured using an electrochemical station (VSP, BioLogic SAS, France) in conjunction with a current booster (VMP3 Booster, BioLogic SAS, France). The current range of the booster was 0 to 80 A. During the test, the anode was 36 mL min -1 It was exposed to a 1M KOH solution circulating at a flow rate. A dry cathode was used to meet industry standards. The IV curve was measured by scanning voltages from 1.3 V to 2.0 V. Electrochemical impedance spectroscopy (EIS) was performed at 60 and 80 °C at 1.6 V and 1.8 V with an amplitude of 50 mV in a frequency range of 1 Hz to 200 kHz. The stability of the AEMWE was 1.0 A cm⁻¹. -2 It was evaluated using CP mode at the current density.

[0292] Electrochemical measurements were performed using a 3-electrode potentiometer (BioLogic SP-200, France). A catalyst loaded in nickel foam (Ni-foam) was used as the working electrode, Ag / AgCl as the reference electrode, and Pt as the counter electrode. The applied voltage was converted to a reversible hydrogen electrode (RHE) scale using the following equation (11).

[0293] E RHE = E Ag / AgCl + 0.05916 Х pH + 0.197 … … Equation (11)

[0294] The scan rate of Linear Sweep Voltage-Current Method (LSV) is 10 mV s-1 was. LSV was performed in a 1M KOH solution. Electrochemical impedance spectroscopy (EIS) was analyzed in a frequency range between 100 Hz and 100 kHz at an AC amplitude of 10 mV. Electrochemical bilayer capacitance (C dl ) was measured using cyclic voltammetry (CV) at various scanning rates in the non-paradic region. The electrochemical active surface area (ECSA) was calculated using the following equation (12).

[0295] ECSA = C dl / 0.04 mF cm -2 … … Equation (12)

[0296] The Tafel slope was calculated through linear fitting based on the following equation (13).

[0297] E = A + B log j … … Equation (13)

[0298] Here, E, A, B, and j correspond to the potential, fitting parameter, Tafel slope, and current density, respectively. The stability of the OER is 100 mA cm⁻¹ for 20 hours. -2 It was tested in CP mode.

[0299] Hydrogen peroxide (H2O2) production during OER was measured using o-toluidine as a redox indicator. A 0.1 M sodium sulfate (Na2SO4) solution at pH 6.55 was used as the electrolyte. Four ml samples of the reacted solution were collected every 30 minutes during the 180-minute OER, mixed with 0.8 ml of a 0.1% (w / v) o-toluidine solution in 1 M HCl, and stirred for one hour. The mixture turned yellow if it contained H2O2, and the concentration was measured using UV-vis spectroscopy.

[0300] FIG. 20 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) Electrode and Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x) electrode and, (b) Preparation Example 1-11 (L-MnO x This is a graph showing the results of X-ray photoelectron spectroscopy (XPS) on the electrode. It can be divided into a total of three parts, analyzed from right to left as oxygen within the lattice, oxygen vacancies, and surface-adsorbed oxygen. The x-axis represents binding energy, and the y-axis represents intensity.

[0301] Preparation Example 1-11 of FIG. 20(b) (L-MnO x ) showed the lowest oxygen vacancy, and Fig. 20(a) Preparation Example 1-1 (L-CoO x ) and Preparation Examples 1-4 (L-Co 0.9 Mn 0.1 O x It can be observed that the oxygen vacancy gradually increases in the order of ). This can be seen as the result of oxygen vacancies occurring as the lattice structure is distorted due to the Jahn-Teller effect, which occurs as the oxidation number of manganese decreases due to the movement of electrons from cobalt to manganese.

[0302] FIG. 21 is Preparation Example 1-1 of the present invention (L-CoO x ) Electrode, Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) electrode, and Preparation Example 1-11 (L-MnO x (a) A graph showing the results measured by an ultraviolet-visible (UV-Vis) spectrophotometer and (b) the results measured by photoluminescence spectroscopy (PL) for the electrode.

[0303] Referring to Figure 21 (a), the electrodes of Preparation Example 1-1, Preparation Example 1-4, and Preparation Example 1-11 all exhibit similar absorbance wavelengths, confirming that the chiral metal oxide thin films formed on the electrodes have similar thicknesses.

[0304] In FIG. 21(b), despite having a similar thin film thickness, Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x It can be confirmed that the electrode of ) exhibits the highest PL intensity photoluminescence wavelength. This can be seen as a result of the fact that, as the largest number of oxygen vacancies are generated in Preparation Example 1-4, another pathway for new electrons and holes to undergo radiative recombination is provided, thereby relatively increasing the photoluminescence intensity.

[0305] FIG. 22 is Preparation Example 1-1 of the present invention (L-CoO x ) Electrode and Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x This is a graph showing the electrode analyzed by Raman spectroscopy.

[0306] Referring to FIG. 22, Preparation Example 1-1 (L-CoO x In ), it appeared as a spinel structure, and Preparation Examples 1-4 (L-Mn 0.1 -Co 0.9 O x In ), the Raman shift moved toward lower wavelengths and showed a wide distribution of wavelengths. This is judged to be the result of oxygen vacancies occurring due to lattice distortion in Preparation Examples 1-4.

[0307] FIG. 23 is Preparation Example 1-1 of the present invention (L-CoO x ) Electrode, Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) Electrode and Preparation Example 1-11 (L-MnO x (a) a graph showing the change in current density according to pH and (b) the change in slope of the efficiency according to pH at 1.6 V (vs. RHE), analyzed in electrolytes with various pH values.

[0308] Referring to FIG. 23 (a) and (b) together, Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x The highest slope was observed at the electrode. This can be interpreted as a phenomenon where the rate at which oxygen vacancies are refilled accelerates as the pH of the electrolyte increases due to the participation of oxygen vacancies in the reaction. Through this, the effect of oxygen vacancies participating in the reaction can be confirmed.

[0309] FIG. 24 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) electrode and (b) Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x This is a graph showing the results of analyzing the electrodes using linear scanning potentiometry (LSV) in 1M KOH and 1M tetramethylammonium hydroxide (TMAOH), respectively.

[0310]

[0311] * By referring to (a) and (b) of Fig. 24 together, it can be confirmed that oxygen vacancies participate in the reaction through the phenomenon of adsorption to oxygen vacancies that reduces efficiency.

[0312] FIG. 25 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) electrode and (b) Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x This is a graph showing the results of real-time Raman analysis (in situ Raman spectroscopy) performed by applying a voltage (0V to 1.7V) to the electrode in the electrolyte.

[0313] Referring to FIG. 25, Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x In the red region only at the electrode * O2 - It can be confirmed that oxygen vacancies participate in the reaction through the phenomenon in which this occurs.

[0314] FIG. 26 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) electrode and (b) Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) electrode in 1M KOH solution and 100mA·cm -2 This is a graph showing the results of analyzing the potential over time under constant current conditions.

[0315] Referring to FIG. 26, Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x In the case of the electrode, it can be confirmed that it exhibits very uniform stability without change.

[0316] FIG. 27 is Preparation Example 1-1 of the present invention (L-CoO x ) Electrode and Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) electrode in 1M KOH solution and 500mA cm -2 This is a graph showing the concentration of dissolved cobalt ions (concentration of Co dissolution) according to time after reacting for 10 hours under constant current conditions.

[0317] FIG. 27 shows the results of analyzing the cobalt concentration of the sample at different times (1 hour, 3 hours, 5 hours, 10 hours), and Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x It can be confirmed that the degree of dissolution of cobalt at the electrode is suppressed.

[0318] FIG. 28 is (a) Preparation Example 1-1 (L-CoO) of the present invention x ) electrode and (b) Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x ) electrode in 1M KOH solution and 500mA·cm -2 This is an image of the electrode surface observed with a scanning electron microscope (SEM) after reacting for 10 hours under constant current conditions.

[0319] Referring to FIG. 28, Preparation Example 1-1 (L-CoO x While physical detachment occurs at the ) electrode, Preparation Example 1-4 (L-Mn 0.1 -Co 0.9 O x It can be confirmed that it is maintained without significant change at the electrode.

[0320] FIG. 29 is a graph showing the normalized absorbance at 400 nm for the electrodeposited L-SPL and spray-coated L-Co3O4 thin films on an FTO glass substrate in Preparation Example 3-1 and Comparative Example 3-1 of the present invention. The X mark in the inset indicates the measurement point. In addition, FIG. 30 is a graph showing the work function of the electrodeposited L-SPL thin film and the spray-coated L-Co3O4 thin film of FIG. 29, and FIG. 31 is a three-dimensional (3D) plot of the work function measured in FIG. 30.

[0321] Referring to FIGS. 29 to 31, the L-SPL thin film electrodeposited on the FTO substrate in Preparation Example 3-1 is 10,000 mm 2 Even over a large area, it can be confirmed that the L-Co3O4 nanoparticle thin film (4.51 eV ± 0.139 eV) prepared by spray coating in Comparative Example 3-1 above exhibits a much more uniform absorption rate and work function (5.27 eV ± 0.087 eV). These results suggest that the high work function of the amorphous thin film containing the chiral metal oxide electrodeposited in Preparation Example 3-1 above may be attributed to trap states induced by defects in the disordered structure, which may imply a higher electron affinity than that of a crystalline thin film.

[0322] FIG. 32 is Preparation Example 4-1 of the present invention (L-CoO x -PTL) and Preparation Example 4-2 (L-Co 0.9 Mn 0.1 Ox -PTL) anode electrode, (a) graph showing the result of linear scanning potentiometry (LSV) analysis in 1M KOH heated to 80°C, (b) 1A cm in 1M KOH heated to 60°C -2 This is a graph showing the stability analysis under constant current conditions.

[0323] Referring to FIG. 32(a), when comparing the current density at 2V, Preparation Example 4-1 (L-CoO x The electrode is 6.21A cm -2 It showed, and Preparation Example 4-2 (L-Co 0.9 Mn 0.1 O x It can be confirmed that the electrode exhibits improved efficiency of 11.15 A cm-2.

[0324] Referring to FIG. 32 (b), Preparation Example 4-1 (L-CoO x As the reaction proceeded, the operating voltage of the electrode gradually decreased. This can be attributed to the cross-linking of oxygen and hydrogen generated at the anode and cathode, respectively, due to membrane damage. In other words, it is determined that the non-uniform electrode surface applied non-uniform pressure to the membrane, thereby accelerating the damage.

[0325] On the other hand, Preparation Example 4-2 (L-Co 0.9 Mn 0.1 O x The electrode demonstrated stable operation for over 1,000 hours. Additionally, it was confirmed that the slight increase in operating voltage was due to a small amount of catalyst layer detaching during the reaction, but it did not significantly affect overall stability.

[0326] FIG. 33 is a graph showing the results of linear scanning voltammetry (LSV) measurements for the anodes of the nickel foam (Ni-foam 10mm x 10mm) of Comparative Example 4-1 of the present invention and Preparation Example 4-1 (L-SP-PTL 10mm x 10mm), Preparation Example 4-3 (L-SP-PTL 30mm x 30mm), and Preparation Example 4-4 (L-SP-PTL 50mm x 50mm) prepared with various surface areas. The inset figure shows Preparation Example 4-1 (100mm 2 ), Preparation Example 4-3 (900mm 2 ) and, Preparation Example 4-4 (2,500mm 2 Represents the anode electrodeposited in ).

[0327]

[0328] * Referring to FIG. 33, the overvoltage of the anode of Preparation Example 4-1 was 325 mV, the overvoltage of the anode of Preparation Example 4-3 was 329 mV, and the overvoltage of the anode of Preparation Example 4-4 was 328 mV, and the electrodeposited L-SP-PTL showed consistent overvoltage across all sizes.

[0329] FIG. 34 is Manufacturing Example 4-4 of the present invention (large area (2500mm²) 2 L-SP-PTL (area = 100 mm) cut from the anode of ) L-SP-PTL) 2 This is the LSV curve of ). The inset shows the points measured at the large-area L-SP-PTL.

[0330] Referring to FIG. 34, a 100 mm cut from the large-area L-SP-PTL of Preparation Example 4-4 2 The sample showed a consistent average overvoltage of 310.8 mV ± 10.2 mV.

[0331] FIG. 35 shows a 100mm section cut from the electrodeposited large-area L-SPL of Preparation Example 3-2 of the present invention and the spray-coated large-area L-Co3O4 electrode of Comparative Example 3-2. 2 This is the result of measuring the overpotential of a thin film having an area.

[0332] Referring to Fig. 35, the overpotential deviation of the spray-coated L-Co3O4 was significantly larger compared to the electrodeposited L-SPL of Preparation Example 3-2. This is believed to be due to the local aggregation of the catalyst on the PTL surface during the spray coating process.

[0333] As described above, the method for forming a chiral metal oxide-based catalyst layer by electrodeposition presented in the present invention can be effectively applied to large-scale water electrolysis and is expected to be commercially viable for industrial use.

[0334] FIG. 36 is a graph comparing the polarization curves of the anion exchange membrane water electrolysis device based on chiral L-NiFe-SP-PTL and D-NiFe-SP-PTL of Preparation Example 5-1 of the present invention and the anion exchange membrane water electrolysis device based on non-chiral meso-NiFe-PTL of Comparative Example 5-1.

[0335] Referring to FIG. 36, the anion exchange membrane water electrolysis apparatus based on the chiral L-NiFe-SP-PTL and D-NiFe-SP-PTL of Preparation Example 5-1 showed 11.04 A cm⁻¹ at 2.0 V, respectively. -2 and 11.5 A cm -2 This represented a current density of 10.83 A cm⁻¹ for the anion exchange membrane water electrolysis device based on the avichiral meso-NiFe-PTL of Comparative Example 5-1. -2 It is a higher value.

[0336] FIG. 37 is an EIS Nyquist plot of an anion exchange membrane water electrolysis apparatus based on the chiral L-NiFe-SP-PTL and D-NiFe-SP-PTL of Preparation Example 5-1 of the present invention and the non-chiral meso-NiFe-PTL of Comparative Example 5-1.

[0337] Referring to FIG. 37, the RCT values ​​of the anion exchange membrane water electrolysis devices using the L-NiFe-SP-PTL and D-NiFe-SP-PTL of Preparation Example 5-1 are 0.014 Ω·cm, respectively. -2and 0.0136 Ω·cm -2 As for the RCT value of the anion exchange membrane water electrolysis device using the avichiral meso-NiFe-PTL of Comparative Example 5-1, it is 0.0177 Ω·cm -2 It was found to be lower. Through this, it can be seen that the chiral NiFe-SP-PTL electrode presented in the present invention exhibits better interfacial charge transfer compared to the non-chiral NiFe-PTL electrode.

[0338] FIG. 38 shows 1M KOH and 1A cm at 60°C for an anion exchange membrane water electrolysis apparatus based on the chiral L-NiFe-SP-PTL and D-NiFe-SP-PTL of Preparation Example 5-1 of the present invention and the achiral meso-NiFe-PTL of Comparative Example 5-1. -2 This is the result of a durability test performed using [method].

[0339] Referring to FIG. 38, the anion exchange membrane water electrolysis device using the L-NiFe-SP-PTL of Preparation Example 5-1 shows a lower operating bias (1.8 V) than the anion exchange membrane water electrolysis device using the meso-NiFe-PTL (1.88 V) of Comparative Example 5-1, with 1 A cm -2 A current density was achieved. In addition, the anion exchange membrane water electrolysis device of Preparation Example 5-1 operated very stably for more than 1,000 hours in a 1 M KOH solution. These results suggest that the chiral metal oxide-based electrode of the present invention is promising for further improving the efficiency of anion exchange membrane water electrolysis devices having spin polarization.

[0340] As described above, the present invention comprises a water electrolysis electrode including a chiral metal oxide-based catalyst layer and effectively introduces it into an anion exchange membrane water electrolysis device. Since the chiral metal oxide-based catalyst layer acts as a spin polarization layer, the electrode including this catalyst layer can inject spin polarization carriers having a high spin polarization rate of 81.4% through chiral-induced spin selectivity (CISS). A high spin polarization rate can promote the generation of spin-polarized hydroxyl radicals, thereby effectively suppressing the generation of byproducts such as hydrogen peroxide (H2O2).

[0341] In addition, the chiral metal oxide-based anion exchange membrane water electrolysis device of the present invention has 8.21 A·cm at 2.0 V (80℃). -2 It exhibited a current of , showing a 52% improved performance compared to a spin nonpolarization, avichiral anode-based spin nonpolarization anion exchange membrane water electrolysis device.

[0342] In addition, the chiral metal oxide-based anion exchange membrane water electrolysis device of the present invention is applicable to industrial applications up to a maximum of 10,000 mm 2 A uniform water electrolysis electrode with a large surface area was realized. These results suggest a new approach to designing spin-polarized anodes for efficient water electrolysis in anion exchange membrane water electrolysis devices.

[0343] Although the present invention has been described in detail with reference to preferred embodiments, the present invention is not limited to the above embodiments, and various modifications and changes are possible by those skilled in the art within the technical spirit and scope of the present invention.

Claims

1. A first electrode comprising an L-type or D-type chiral metal oxide-based catalyst layer; A second electrode provided spaced apart from the first electrode; An anion exchange membrane provided between the first electrode and the second electrode; and The apparatus comprises the first electrode, the anion exchange membrane, and an electrolyte filled within the second electrode; An anion exchange membrane water electrolysis device, wherein the above chiral metal oxide is represented by the following chemical formula 1: [Chemical Formula 1] M 1 M 2 O x In the above chemical formula 1, The above M 1 and the above M 2 It is composed of two different metallic elements, and The above M 1 It is any one selected from Co, Ni, and Mn, and The above M 2 is the above M 1 It is a metal atom having an atomic radius that is greater than 0% and less than 15% of the difference from the atomic radius of, and The above x is an integer from 1 to 10.

2. In Paragraph 1, The above M 2 An anion exchange membrane water electrolysis device, wherein is any one metal atom selected from Co, Mn, Ni, Li, Mg, Al, Sc, Ti, V, Cr, Fe, Cu, Zn, Ga, Ge, As, Se, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Sn, Sb, Te, Hf, Ta, W, Re, Os, Ir, Pt, Au, Bi, Po, At, U, Np, and Pu.

3. In Paragraph 1, The above chiral metal oxide is CoMnO x , CoNiO x , NiCoO x , and NiMnO x An anion exchange membrane water electrolysis device comprising any one selected from among.

4. In Paragraph 3, The above chiral metal oxide is Co 1-y Mn y O x is, An anion exchange membrane water electrolysis device in which y is 0.01 to 0.

8.

5. In Paragraph 4, The above chiral metal oxide is Co 0.9 Mn 0.1 O x Phosphorus, anion exchange membrane water electrolysis device.

6. In paragraph 1, the first electrode is, An anion exchange membrane water electrolysis device further comprising a porous transport layer disposed on one side of the chiral metal oxide-based catalyst layer and supporting the catalyst layer.

7. In paragraph 6, the porous transport layer is, An anion exchange membrane water electrolysis device comprising one or more of metals, polymers, and carbon bodies.

8. In paragraph 1, the anion exchange membrane is, An anion exchange membrane water electrolysis device comprising one or more of quaternary ammonium, imidazolium, benzimidazole, polyimide, polystyrene, polylynorbornene, polyethylene, and polysiloxane based on a polymer backbone composed of poly(phenylene oxide), poly(ether ether ketone), poly(acryl ether sulfone), polybenzimidazole, polyimide, polystyrene, polylynorbornene, polyethylene, and polysiloxane.

9. A step of forming a mixed solution by mixing a metal oxide precursor, a chiral organic material, and an alkalizing agent; A step of forming an L-type or D-type chiral metal oxide-based catalyst layer by electrodepositing the above mixed solution onto a substrate to provide a first electrode; A step of providing an anion exchange membrane on one side of the first electrode; A step of providing a second electrode on one side of the anion exchange membrane, spaced apart from the first electrode; and The method includes the step of filling the first electrode, the anion exchange membrane, and the second electrode with an electrolyte; A method for manufacturing an anion exchange membrane water electrolysis device, wherein the above chiral metal oxide is represented by the following chemical formula 1: [Chemical Formula 1] M 1 M 2 O x In the above chemical formula 1, The above M 1 and the above M 2 It is composed of two different metallic elements, and The above M 1 It is any one selected from Co, Ni, and Mn, and The above M 2 is the above M 1 It is a metal atom having an atomic radius that is greater than 0% and less than 15% of the difference from the atomic radius of, and The above x is an integer from 1 to 10.

10. In Paragraph 9, A method for manufacturing an anion exchange membrane water electrolysis device, wherein the chiral organic material is L-type tartaric acid or D-type tartaric acid.

11. In Paragraph 9, The above alkalizing agents are sodium carbonate (Na2CO3), potassium carbonate (K2CO3), sodium bicarbonate (NaHCO3), and sodium phosphate (Na5P3O2). 10 A method for manufacturing an anion exchange membrane water electrolysis device comprising one or more selected from sodium pyrophosphate (Na4P2O7), disodium phosphate (K2HPO4), disodium phosphate (Na2HPO4), sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), trisodium citrate (C6Na3H5O7), and sodium metaphosphate (NaPO3)6).

12. In Paragraph 9, A method for manufacturing an anion exchange membrane water electrolysis device, wherein the above substrate is a porous transport layer.

13. In Clause 12, the porous transport layer is, A method for manufacturing an anion exchange membrane water electrolysis device comprising one or more of metals, polymers, and carbon bodies.

14. In claim 9, the anion exchange membrane is, A polymer comprising one or more of poly(phenylene oxide), poly(ether ether ketone), poly(acryl ether sulfone), polybenzimidazole, polyimide, polystyrene, polylynorbornene, polyethylene, and polysiloxane, wherein the backbone formed by the polymer comprises one or more functional groups selected from quaternary ammonium, imidazolium, benzimidazolium, piperidinium, guanidinium, phosphonium, sulfonium, and triazolium. Method for manufacturing an anion exchange membrane water electrolysis device.

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