Symmetric ammonia electrolysis system based on plasmonic phenomenon

Abstract

The present application relates to a plasmonic phenomenon-based symmetric ammonia electrolysis system and an ammonia electrolysis method using same. A hybrid electrode, according to embodiments of the present application and the symmetric ammonia electrolysis system comprising same, may reactivate the surface of a catalyst by utilizing plasmonic phenomena during an electrochemical reaction by using a plasmonic-active electrode (antenna-reactor) composite electrode.

Description

Symmetric ammonia electrolysis system based on plasmonic phenomena

[0001] The present invention relates to a symmetric ammonia electrolysis system based on a plasmonic phenomenon and an ammonia electrolysis method using the same.

[0002] To increase the volumetric energy density of hydrogen during transport, it is typically converted to a liquid hydrogen carrier. This is because gaseous hydrogen has a limited storage capacity, making it difficult to transport large quantities. Consequently, methods for storing and transporting hydrogen, such as liquefied hydrogen, ammonia, and liquid organic hydrogen carriers (LOHC), are gaining attention. Among these, ammonia-based hydrogen storage, transportation, and extraction are attracting particular attention. Ammonia storage allows for approximately 1.7 times more hydrogen to be stored than liquefied hydrogen. Furthermore, the global export and import of ammonia is actively taking place, and the infrastructure, including production facilities and transport vessels, is in place. Therefore, utilizing ammonia as a hydrogen carrier can ensure economical hydrogen supply.

[0003] Methods for producing hydrogen from ammonia can be broadly categorized into thermal decomposition, alkali metal amide process, and electrolysis. Thermal decomposition utilizes high temperatures exceeding 400°C to decompose ammonia, necessitating the use of a catalyst. Alkali metal amide process utilizes an exothermic reaction with alkali metal hydride to decompose ammonia at room temperature, but has the disadvantage of low economic efficiency. Electrolysis utilizes ammonia as an electrolyte, and operates at low temperatures, resulting in good stability and efficiency. However, most prior inventions related to ammonia electrolysis have simply utilized the activity of metal catalysts, such as the development of gold-platinum mixed catalysts, photoreaction-based hydrogen production, and use as electrochemical ammonia electrolysis catalysts.

[0004] [Prior Art Literature]

[0005] [Patent Document]

[0006] Republic of Korea Patent Publication No. 2160870.

[0007] The present invention aims to provide a symmetric ammonia electrolysis system based on plasmonic phenomena and an ammonia electrolysis method using the same.

[0008] However, the problems that the present invention seeks to solve are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

[0009] The first aspect of the present invention provides a symmetrical ammonia electrolysis system comprising: an electrolyte section including an electrolyte solution containing ammonia; a first hybrid electrode including a hybrid electrode; and a second hybrid electrode including a hybrid electrode, wherein the first hybrid electrode and the second hybrid electrode are symmetrically positioned with respect to the electrolyte section, the hybrid electrode includes a substrate, a catalyst layer formed on the substrate, and plasmonic nanoparticles formed on the catalyst layer, and electrons excited by a plasmon phenomenon of the plasmonic nanoparticles are transferred to the catalyst layer.

[0010] The second aspect of the present invention provides an ammonia electrolysis method using a symmetrical ammonia electrolysis system according to the first aspect.

[0011] The hybrid electrode and the symmetric ammonia electrolysis system including the same according to the embodiments of the present invention may reactivate the catalyst surface by utilizing the plasmonic phenomenon during an electrochemical reaction using a plasmonic-active electrode (antenna-reactor) composite electrode.

[0012] The symmetric ammonia electrolysis system according to the embodiments of the present invention can improve the activity and life of the electrode by transferring electrons generated by plasmonic excitation of plasmonic nanoparticles to the catalyst layer and removing oxidation reaction intermediates from the catalyst layer.

[0013] A symmetrical ammonia electrolysis system according to embodiments of the present invention comprises two identical hybrid electrodes symmetrically arranged around the electrolyte portion, wherein the two hybrid electrodes function as a cathode and an anode, respectively, and their roles may be switched by changing the voltage direction of an external power source. Accordingly, poisoning caused by nitrogen oxides generated at the anode can be prevented, and the performance and stability of the electrolysis system can be significantly improved.

[0014] Figure 1 is a schematic diagram of a synthesis process of a deposited Pt(reactor)-Au(antenna) catalyst in one embodiment of the present invention (a); XRD patterns of each electrode including Ti fiber felt, Pt on Ti felt, and Pt-Au on Ti felt (b); SEM images of Pt on Ti felt (c and d); and SEM images of Pt-Au on Ti felt (e and f) (the inset in f indicates the atomic ratio of each element in the SEM-EDS profile).

[0015] Figure 2 is a schematic diagram of a symmetrical ammonia electrolyzer according to one embodiment of the present invention.

[0016] Figure 3 shows a design diagram of a symmetrical ammonia electrolyzer according to one embodiment of the present invention.

[0017] Figures 4a and 4b are a photograph (a) of a symmetrical ammonia electrolyzer and a photograph (b) of the electrolyzer being operated while irradiating light, in one embodiment of the present invention.

[0018] Figures 5 a and b show current values ​​according to applied voltage under low-concentration ammonia (a) and high-concentration ammonia (b) conditions of a symmetrical ammonia electrolyzer in one embodiment of the present invention.

[0019] Figure 6 shows the ammonia concentration and ammonia removal efficiency according to the operating time of a symmetrical ammonia electrolyzer in one embodiment of the present invention.

[0020] FIG. 7 shows, in one embodiment of the present invention, the driving voltage in the ammonia oxidation (anodic potential), hydrogen production (cathodic potential), and electrode reactivation (cell potential) reactions of a symmetrical ammonia electrolyzer is evaluated.

[0021] Figures 8a to 8f show, in one embodiment of the present invention, UV-vis absorbance (a, c, e) according to the operating time when a symmetrical ammonia electrolyzer is operated; and absorbance and ammonia concentration (b, d, f) according to the time in each measurement.

[0022] Figure 9 shows, in one embodiment of the present invention, the ammonia removal efficiency and average value (a) according to the measurement order when operating a symmetrical ammonia electrolysis; and the ammonia concentration (b).

[0023] Figure 10 shows, in one embodiment of the present invention, the ammonia removal rate according to the plasmonic thermal ignition effect and the ammonia removal rate when the symmetric ammonia electrolysis of the present invention is driven.

[0024] Hereinafter, with reference to the attached drawings, implementation examples and embodiments of the present invention will be described in detail so that those skilled in the art can easily practice the present invention. However, the present invention may be implemented in various different forms and is not limited to the implementation examples and embodiments described herein. In addition, in the drawings, parts irrelevant to the description have been omitted to clearly explain the present invention, and similar parts have been designated with similar drawing reference numerals throughout the specification.

[0025] Throughout this specification, when a part is said to be "connected" to another part, this includes not only cases where it is "directly connected" but also cases where it is "electrically connected" with another element in between.

[0026] Throughout this specification, when it is said that an element is "on" another element, this includes not only cases where the element is in contact with the other element, but also cases where another element exists between the two elements.

[0027] Throughout this specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0028] The terms "about," "substantially," and the like used in this specification are used in a meaning that is at or close to the numerical value when manufacturing and material tolerances inherent in the meanings mentioned are presented, and are used to prevent unscrupulous infringers from unfairly exploiting the disclosure in which exact or absolute values ​​are mentioned to aid understanding of the present application.

[0029] The terms “step of ~” or “step of ~” as used throughout this specification do not mean “step for ~.”

[0030] Throughout this specification, the term "combination(s) thereof" included in the expressions in the Makushi format means one or more mixtures or combinations selected from the group consisting of the components described in the expressions in the Makushi format, and means including one or more selected from the group consisting of said components.

[0031] Throughout this specification, references to “A and / or B” mean “A or B, or A and B.”

[0032] Below, the implementation examples of the present invention are described in detail, but the present invention may not be limited thereto.

[0033] The first aspect of the present invention provides a symmetrical ammonia electrolysis system comprising: an electrolyte section including an electrolyte solution containing ammonia; a first hybrid electrode including a hybrid electrode; and a second hybrid electrode including a hybrid electrode, wherein the first hybrid electrode and the second hybrid electrode are symmetrically positioned with respect to the electrolyte section, the hybrid electrode includes a substrate, a catalyst layer formed on the substrate, and plasmonic nanoparticles formed on the catalyst layer, and electrons excited by a plasmon phenomenon of the plasmonic nanoparticles are transferred to the catalyst layer.

[0034] In one embodiment of the present invention, the substrate may be used without limitation as long as it is used as a substrate for an electrode in the relevant industry, and non-limiting examples thereof include carbon-based materials; metals including Ti, Ni, or Cu; inorganic oxides including oxides such as Ti, Zr, Al, or Si; or perovskite oxides and zeolites.

[0035] In one embodiment of the present invention, the carbon-based material may include one or more selected from graphite, carbon fiber, carbon sheet, carbon black, carbon nanotube (CNT), carbon sphere, carbon ribbon, fullerene, active carbon, carbon nanowire, and graphene, but may not be limited thereto.

[0036] In one embodiment of the present invention, the substrate may be in the form of a fluid passage, but may not be limited thereto. Here, the fluid passage may be included in the substrate at least once. In one embodiment of the present invention, the substrate may be in the form of a mesh structure, but may not be limited thereto.

[0037] In one embodiment of the present invention, the substrate may be formed of Ti fibers, Ni fibers, or Pt fibers in a mesh structure, but may not be limited thereto.

[0038] In one embodiment of the present invention, the catalyst layer may include one or more selected from Pt, Pd, Ir, Ag, Ru, Ni, Cu, Mn, Co, Fe, and alloys thereof, but may not be limited thereto.

[0039] In one embodiment of the present invention, the plasmonic nanoparticles may include one or more selected from Au, Ag, Pt, Pd, Rh, Re, Cu, Al, Mg, In, Ga, Ni, and Rb, but may not be limited thereto.

[0040] In one embodiment of the present invention, the diameter distribution of the plasmonic nanoparticles may be from about 5 nm to about 140 nm, and the number of the plasmonic nanoparticles having a diameter of from about 40 nm to about 90 nm may be at least about 50% of the total number of the plasmonic nanoparticles.

[0041] In one embodiment of the present invention, the diameter of the plasmonic nanoparticles may vary depending on the light irradiation conditions (light wavelength or light type, etc.) when driving the hybrid electrode and / or the type of the plasmonic nanoparticles. In one embodiment of the present invention, as a structural design capable of increasing surface plasmonic efficiency under actual solar irradiation conditions (1 Sun), the average diameter of the plasmonic nanoparticles may be about 60 nm to about 80 nm.

[0042] In one embodiment of the present invention, when the first hybrid electrode operates as an anode, the second hybrid electrode operates as a cathode; or when the first hybrid electrode operates as a cathode, the second hybrid electrode may operate as an anode.

[0043] The symmetric ammonia electrolysis system according to the embodiments of the present invention includes two identical hybrid electrodes symmetrically centered around the electrolyte portion, and the two hybrid electrodes operate as a cathode and an anode, respectively, and then their roles can be switched by changing the voltage direction of an external power source.

[0044] In one embodiment of the present invention, an ammonia oxidation reaction may occur at the anode to form nitrogen gas and water, and a water reduction reaction may occur at the cathode to form hydrogen gas. In this case, the reaction formulas at the anode and cathode are as follows:

[0045] Anode: 2NH3+ 6OH -→ N2+ 6H2O + 6e -

[0046] Cathode: 6H2O + 6e - → 3H2+ 6OH -

[0047] In one embodiment of the present invention, continuous nitrogen oxide (NO) is formed on the catalyst layer due to the strong N bond generated at the anode. x ) intermediates may be generated, resulting in a poisoning phenomenon. The nitrogen oxides may block the catalytically active surface, thereby causing a decrease in the catalytic activity of the electrode. The symmetric ammonia electrolysis system according to the embodiments of the present disclosure can improve the activity and life of the electrode by transferring electrons generated by the plasmon excitation of the plasmonic nanoparticles to the catalyst layer, thereby removing nitrogen oxide intermediates from the catalyst layer.

[0048] In addition, in the symmetrical ammonia electrolysis system according to the embodiments of the present invention, since the first hybrid electrode and the second hybrid electrode alternately operate as an anode and a cathode, respectively, the poisoning phenomenon due to nitrogen oxides is prevented, and the performance and stability of the electrolysis system can be significantly improved.

[0049] In one embodiment of the present invention, the ammonia concentration of the electrolyte may be, but is not limited to, about 0.01 M to about 2 M. In one embodiment of the present invention, the ammonia concentration of the electrolyte may be, but is not limited to, about 0.01 M to about 2 M, about 0.01 M to about 1.5 M, about 0.01 M to about 1 M, about 0.01 M to about 0.5 M, about 0.1 M to about 2 M, about 0.1 M to about 1.5 M, about 0.1 M to about 1 M, or about 0.1 M to about 0.5 M.

[0050] In one embodiment of the present invention, the electrolyte may further include an electrolyte comprising an alkali hydroxide.

[0051] In one embodiment of the present invention, the alkali hydroxide may include one or more selected from KOH, NaOH, and Ca(OH)2, but may not be limited thereto.

[0052] In one embodiment of the present invention, the concentration of the alkali hydroxide may be from about 0.1 M to about 10 M, but may not be limited thereto.

[0053] In one embodiment of the present invention, the electrolyte may flow within the electrolyte portion and contact the first hybrid electrode and the second hybrid electrode, respectively.

[0054] In one embodiment of the present invention, the flow rate of the electrolyte may be from about 1 mL / min to about 300 mL / min, but may not be limited thereto. In one embodiment of the present invention, the flow rate of the electrolyte is from about 1 mL / min to about 300 mL / min, from about 1 mL / min to about 250 mL / min, from about 1 mL / min to about 200 mL / min, from about 1 mL / min to about 150 mL / min, from about 1 mL / min to about 100 mL / min, from about 1 mL / min to about 80 mL / min, from about 10 mL / min to about 300 mL / min, from about 10 mL / min to about 250 mL / min, from about 10 mL / min to about 200 mL / min, from about 10 mL / min to about 150 mL / min, from about 10 mL / min to about 100 mL / min, from about 10 mL / min to about 80 mL / min, from about 30 mL / min to about 300 mL / min, from about 30 mL / min to about 250 mL / min, about 30 mL / min to about 200 mL / min, about 30 mL / min to about 150 mL / min, about 30 mL / min to about 100 mL / min, about 30 mL / min to about 80 mL / min, about 40 mL / min to about 300 mL / min, about 40 mL / min to about 250 mL / min, about 40 mL / min to about 200 mL / min, about 40 mL / min to about 150 mL / min, about 40 mL / min to about 100 mL / min, or about 40 mL / min to about 80 mL / min, but may not be limited thereto.

[0055] In one embodiment of the present invention, the symmetrical ammonia electrolysis system may further include an inlet and an outlet for the electrolyte. In one embodiment of the present invention, the inlet and the outlet may be formed on the upper and / or lower portions of the first hybrid electrode or the second hybrid electrode. For example, the symmetrical ammonia electrolysis system may include a first outlet on the upper portion and a first inlet on the lower portion of the first hybrid electrode, and a second outlet on the upper portion and a second inlet on the lower portion of the second hybrid electrode.

[0056] In one embodiment of the present invention, the outlet may be an outlet for not only the electrolyte but also N2 gas and / or H2 gas generated from the first hybrid electrode and the second hybrid electrode. In one embodiment of the present invention, the electrolyte may be introduced into the inlet, and the product gas, which is N2 gas or H2 gas, and / or the remaining electrolyte after the reaction may be introduced into the outlet.

[0057] In one embodiment of the present invention, the symmetrical ammonia electrolysis system may additionally include a power supply unit.

[0058] In one embodiment of the present invention, the symmetrical ammonia electrolysis system may additionally include a light irradiation unit.

[0059] In one embodiment of the present invention, the symmetric ammonia electrolysis system may further include a window that transmits light on at least one side of the first hybrid electrode and the second hybrid electrode.

[0060] The second aspect of the present invention provides an ammonia electrolysis method using a symmetrical ammonia electrolysis system according to the first aspect.

[0061] Detailed explanations of parts that overlap with the first aspect of the present application have been omitted, but the contents described in the first aspect of the present application may be equally applied even if the explanation is omitted in the second aspect of the present application.

[0062] In one embodiment of the present invention, the ammonia electrolysis method may apply a voltage of about |1| V or more to the symmetrical ammonia electrolysis system.

[0063] In one embodiment of the present invention, the ammonia electrolysis method may apply a voltage of about |1| V or more, about |1| V to about |10| V, about |1| V to about |9| V, about |1| V to about |8| V, about |1| V to about |7| V, about |1| V to about |6| V, about |1| V to about |5| V, about |1| V to about |4| V, about |1| V to about |3| V, or about |1| V to about |2| V to the symmetrical ammonia electrolysis system.

[0064] In one embodiment of the present invention, the voltage range may be a range in which all three reactions of ammonia oxidation at the anode, hydrogen production at the cathode, and electrode reactivation can occur during ammonia electrolysis.

[0065] In one embodiment of the present invention, the ammonia electrolysis method may be to alternately apply the voltage in directions at intervals of about 1 minute to about 60 minutes.

[0066] In one embodiment of the present invention, the voltage may be applied alternately in directions at intervals of about 1 minute to about 60 minutes, about 1 minute to about 50 minutes, about 1 minute to about 40 minutes, about 1 minute to about 30 minutes, about 1 minute to about 20 minutes, about 1 minute to about 10 minutes, about 5 minutes to about 60 minutes, about 5 minutes to about 50 minutes, about 5 minutes to about 40 minutes, about 5 minutes to about 30 minutes, about 5 minutes to about 20 minutes, or about 5 minutes to about 10 minutes.

[0067] In one embodiment of the present invention, the voltage application in the ammonia electrolysis method may be, for example, about +1 V and about -1 V alternately driven at intervals of about 10 minutes, but may not be limited thereto.

[0068] In one embodiment of the present invention, the electrolyte flows within the electrolyte section and contacts the first hybrid electrode and the second hybrid electrode, respectively, and the flow rate of the electrolyte may be about 1 mL / min to about 300 mL / min.

[0069] Hereinafter, the present invention will be described in more detail using examples. However, the following examples are provided only to help understand the present invention, and the contents of the present invention are not limited to the following examples.

[0070] [Example]

[0071] <Example 1: Fabrication of a hybrid electrode including a plasmonic antenna (Au) and an ammonia oxidation reactor (Pt)>

[0072] A mesh-structured substrate was fabricated using Ti fibers. Subsequently, Pt was deposited on the Ti fibers through electrodeposition, and Au nanostructures were supported thereon to fabricate a hybrid electrode comprising a plasmonic antenna (Au) and an ammonia oxidation reactor (Pt) (Fig. 1a).

[0073] The detailed process of Pt electrodeposition is as follows:

[0074] 1) A batch-type three-electrode electrochemical system was constructed.

[0075] - Ti electrode (working electrode)

[0076] - Ag / AgCl electrode (reference electrode)

[0077] - Graphite electrode (counter electrode)

[0078] 2) The electrode was immersed in 5 mM H2PtCl6 electrolyte.

[0079] 3) Pt was deposited using a cyclic voltammetry method for 100 cycles at a rate of 100 mV / s in the range of -1.0 V to -0.2 V (vs. Ag / AgCl electrode).

[0080] The detailed process of depositing Au on Pt is as follows:

[0081] 1) A three-electrode electrochemical system in the form of a batch was constructed.

[0082] - Pt on Ti electrode (working electrode)

[0083] - Ag / AgCl electrode (reference electrode)

[0084] - Graphite electrode (counter electrode)

[0085] 2) The electrode was immersed in 1 mM HAuCl4+ 0.05 M PBS electrolyte.

[0086] 3) Au was deposited using 80 cycles of cyclic voltammetry at a rate of 50 mV / s in the range of -0.855 V to -0.055 V (vs. Ag / AgCl electrode).

[0087] Referring to Fig. 1b, it can be confirmed that Pt and Au are deposited on a Ti substrate. Referring to Fig. 1c to f, the average diameter of the Au nanoparticles is approximately 70 nm, and the diameter distribution ranges from a minimum of 5 nm to a maximum of 140 nm.

[0088] <Example 2: Fabrication of a plasmonic-based symmetric ammonia electrolyzer>

[0089] A plasmonic-based symmetric ammonia electrolyzer was fabricated, each including the hybrid electrode fabricated in Example 1 as a cathode and an anode. Fig. 2 is a schematic diagram of the electrolyzer, in which electrodes (anode and cathode), a current collector, a gasket, a quartz window, and a cell frame are symmetrically positioned on both sides with respect to an electrolyte flow field located at the center.

[0090] The electrolyte is injected into the lower ends of the system and flows in the form of a flow. The injected electrolyte passes through the electrolyte flow field located at the center of the system and is discharged again to the upper ends of the system on both sides. The electrolyte used was 1 M KOH + 50 mM NH4OH. The electrolyte flow field was installed to increase the contact between the electrolyte and the electrode, and the current collector serves as a circuit so that the electrode and the equipment can be connected externally. The electrolytic cell of the present invention includes hybrid electrodes in a symmetrical shape, and oxidation and reduction reactions can be performed at both electrodes, thereby changing the current flow and driving. In addition, light can pass through the quartz window to implement a plasmonic phenomenon.

[0091] Figure 3 is a schematic diagram of an electrolytic cell. Figure 4a is a photograph of the electrolytic cell, and Figure 4b is a photograph of the electrolytic cell being operated while irradiating it with light.

[0092] Experimental Example 1: Confirmation of operation of the electrolyzer under high and low ammonia concentration conditions.

[0093] The operation of the electrolytic cell manufactured in Example 2 under high and low ammonia concentration conditions was confirmed. Figures 5a and b show current values ​​according to the applied voltage under low ammonia (2210 ppm NH3) and high ammonia (0.5 M NH3) conditions, respectively. Under low ammonia concentration conditions, the maximum current value was approximately 520 mA, and under high ammonia concentration conditions, the maximum current value was approximately 600 mA.

[0094] Experimental Example 2: Confirmation of ammonia removal performance under low ammonia concentration conditions in an electrolytic cell.

[0095] The ammonia removal performance of the electrolytic cell manufactured in Example 2 was evaluated under low-concentration ammonia (2210 ppm NH3) conditions. The electrolytic cell was operated alternately at +1 V and -1 V at 10-minute intervals, and light was irradiated in both directions of the electrolytic cell using a solar simulator (1.5 M filter). Approximately 200 mL of electrolyte was used per cycle, and it flowed in the electrolytic cell at a rate of approximately 20 mL / min. The ammonia concentration in the electrolyte was measured in real time, and the ammonia removal efficiency was evaluated (Fig. 6). A total of six evaluations were performed, and an average ammonia removal efficiency of approximately 92% was achieved. Since the ammonia removal performance under low-concentration ammonia conditions was excellent, it was confirmed that the electrolytic cell of the present invention can be utilized for ammonia removal in wastewater.

[0096] Experimental Example 3: Optimization of Electrolyzer Operating Conditions

[0097] In Example 2, a three-electrode electrolysis system was established by adding an Ag / AgCl electrode as a reference electrode in the electrolytic cell, and a voltage range was confirmed in which all three reactions, ammonia oxidation reaction, hydrogen production reaction, and electrode reactivation, could occur during the ammonia electrolysis reaction. From a range of approximately 1 V or higher, the oxidation electrode was driven in the ammonia electrolysis voltage range, and the reduction electrode entered the hydrogen production reaction and electrode reactivation ranges. Therefore, referring to Fig. 7, it was confirmed that an environment suitable for all three reactions was established from a range of approximately 1 V or higher.

[0098] Experimental Example 4: Ammonia Removal Performance Verification

[0099] Under the same conditions as Experimental Example 2, the ammonia concentration in the electrolyte was measured in real time through UV-vis measurement. Figures 8a to f show the UV-vis absorbance (a, c, e) according to the operating time when a symmetrical ammonia electrolyzer is operated in one embodiment of the present invention; and the absorbance and ammonia concentration (b, d, f) according to the time in each measurement. Referring to Figure 8, it was confirmed that the ammonia concentration continuously decreased as the electrolysis system was operated. For the reproducibility experiment, tests were performed several times by grouping a and b, c and d, and e and f, and the same results were obtained.

[0100] Figure 9 shows, in one embodiment of the present invention, the ammonia removal efficiency and average value (a) according to the number of measurement orders when driving a symmetrical ammonia electrolysis; and the ammonia concentration (b). Figure 9b shows the ammonia removal rate converted by determining the reduced ammonia concentration through each electrolysis driving measurement. Referring to Figure 9, the reproducibility was confirmed by performing a total of 6 tests, and the ammonia removal rate was 2.73 uL NH on average. 3(aq) h -1 cm -2 It was.

[0101] Experimental Example 5: Ammonia Electrolysis Performance Verification

[0102] When operating an ammonia electrolysis system utilizing the plasmonic phenomenon, ammonia is electrically decomposed and heat is generated at the electrodes as a secondary effect. This heat can evaporate ammonia dissolved in the electrolyte, ultimately reducing the ammonia concentration in the electrolyte. Therefore, under the conditions of Experimental Example 2, only light was irradiated without electrolysis, and the remaining conditions were kept the same, and the ammonia removal rate according to the thermal ignition effect of the plasmonic phenomenon was confirmed.

[0103] Within the graph, the graph of the plasmonic excitation condition under thermal conditions (Plasmonic excitation (Thermal)) is the ammonia removal rate when only the temperature of the electrolyte is increased (condition of only light irradiation without electrolysis), and the graph regarding the plasmonic-assisted electrochemical AOR (Plasmonic-assisted electrochemical AOR) shows the ammonia removal rate when the plasmonic phenomenon-based electrolysis system is driven. In the latter case, approximately 2.38 uL NH 3(aq) h -1 cm -2 As a speed of , the thermal ignition condition of electrons (0.56 uL NH 3(aq) h -1 cm -2 ) showed a speed about 4.25 times faster than that of conventional electrochemical electrolysis. Therefore, it can be confirmed that most ammonia removal is ammonia removal through electrochemical electrolysis.

[0104] The above description of the present invention is for illustrative purposes only, and those skilled in the art will readily appreciate that the present invention can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single entity may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined manner.

[0105] The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

Claims

1. An electrolyte part including an electrolyte solution containing ammonia; a first hybrid electrode including a hybrid electrode; and a second hybrid electrode including a hybrid electrode. A symmetrical ammonia electrolysis system comprising: The first hybrid electrode and the second hybrid electrode are symmetrically present with the electrolyte portion as the center, The above hybrid electrode includes a substrate, a catalyst layer formed on the substrate, and plasmonic nanoparticles formed on the catalyst layer. The electrons generated by the plasmon phenomenon of the above plasmonic nanoparticles are transferred to the catalyst layer. Symmetric ammonia electrolysis system.

2. In paragraph 1, The above description is a symmetrical ammonia electrolysis system having a form including a fluid movement passage.

3. In paragraph 1, A symmetrical ammonia electrolysis system, wherein the catalyst layer comprises at least one selected from Pt, Pd, Ir, Ag, Ru, Ni, Cu, Mn, Co, Fe, and alloys thereof.

4. In paragraph 1, A symmetric ammonia electrolysis system, wherein the plasmonic nanoparticles include at least one selected from Au, Ag, Pt, Pd, Rh, Re, Cu, Al, Mg, In, Ga, Ni, and Rb.

5. In paragraph 1, The diameter distribution of the above plasmonic nanoparticles is 5 nm to 140 nm, A symmetric ammonia electrolysis system, wherein the number of plasmonic nanoparticles having a diameter of 40 nm to 90 nm is 50% or more of the total number of plasmonic nanoparticles.

6. In paragraph 1, A symmetric ammonia electrolysis system, wherein the average diameter of the above plasmonic nanoparticles is 60 nm to 80 nm.

7. In paragraph 1, If the first hybrid electrode operates as an anode, the second hybrid electrode operates as a cathode; or Wherein the first hybrid electrode operates as a cathode, and the second hybrid electrode operates as an anode. Symmetric ammonia electrolysis system.

8. In paragraph 1, A symmetrical ammonia electrolysis system, wherein the ammonia concentration of the electrolyte is 0.01 M to 2 M.

9. In paragraph 1, A symmetrical ammonia electrolysis system, wherein the electrolyte further comprises an electrolyte containing an alkali hydroxide.

10. In paragraph 1, A symmetrical ammonia electrolysis system, wherein the electrolyte flows within the electrolyte section and contacts the first hybrid electrode and the second hybrid electrode, respectively.

11. In paragraph 10, A symmetrical ammonia electrolysis system, wherein the flow rate of the electrolyte is 1 mL / min to 300 mL / min.

12. In paragraph 10, A symmetrical ammonia electrolysis system further comprising an inlet and outlet for the electrolyte.

13. In paragraph 1, A symmetrical ammonia electrolysis system including an additional power supply unit.

14. In paragraph 1, A symmetrical ammonia electrolysis system including an additional light irradiation unit.

15. In paragraph 1, A symmetrical ammonia electrolysis system further comprising a window transmitting light to at least one side of the first hybrid electrode and the second hybrid electrode.

16. An ammonia electrolysis method using a symmetrical ammonia electrolysis system according to paragraph 1.

17. In paragraph 16, An ammonia electrolysis method, wherein a voltage of |1|V or more is applied to the above symmetrical ammonia electrolysis system.

18. In paragraph 16, An ammonia electrolysis method wherein the voltage is applied alternately in the direction at intervals of 1 to 60 minutes.

19. In paragraph 16, The electrolyte flows within the electrolyte portion and contacts the first hybrid electrode and the second hybrid electrode, respectively. An ammonia electrolysis method, wherein the flow rate of the electrolyte is 1 mL / min to 300 mL / min.

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