A method for optimizing a solid oxide ammonia electrolyzer with improved hydrogen production capacity of cathode

Abstract

The application provides a solid oxide ammonia electrolysis cell optimization method for improving hydrogen production capacity of a cathode, comprising constructing a base reaction model of a proton conductor type solid oxide ammonia electrolysis cell, verifying the base reaction model through experimental data, and optimizing and regulating operation parameters and / or material characteristics of the electrolysis cell based on the verified base reaction model; the optimization and regulation comprises at least one of the following methods: reducing a hydrogen adsorption and desorption rate of an anode material; improving a charge transfer reaction capacity of the anode material; increasing a cathode thickness; improving an ionic conductivity of an electrolyte; improving a charge transfer reaction capacity of a cathode material; and optimizing a hydrogen adsorption and desorption capacity of the cathode material. The technical solution can solve the problems of serious anode hydrogen escape, low cathode hydrogen production efficiency and high electrolysis energy consumption in the existing proton conductor type solid oxide ammonia electrolysis process, and realizes the improvement of hydrogen product selectivity and the optimization of operation efficiency.

Description

Technical Field

[0001] This invention relates to the field of solid oxide electrolysis technology, and in particular to an optimization method for solid oxide ammonia electrolyzers that improves the hydrogen production capacity of the cathode. Background Technology

[0002] Hydrogen energy is a promising clean energy source to replace traditional fossil fuels, but its storage and transportation costs are relatively high. Ammonia, a carbon-free fuel rich in hydrogen, boasts advantages such as high safety and mature production and storage technologies, making it a highly advantageous carrier for hydrogen storage. Traditional ammonia pyrolysis for hydrogen production requires multiple separation steps to obtain the product, while solid oxide electrolysis hydrogen production technology allows for simultaneous reaction and separation, yielding pure hydrogen in a single step. Due to its high-temperature operating characteristics, solid oxide electrolysis technology offers advantages in reaction energy consumption, efficiency, and fuel yield. Thermodynamically, neglecting phase transitions, the total energy requirement of the electrolysis reaction remains essentially constant with increasing temperature, while the electrical energy requirement gradually decreases and the corresponding heat requirement gradually increases. Kinetically, high temperatures help improve reaction kinetics, reduce electrolysis polarization losses, thereby increasing the electrolysis rate and reducing electrolysis energy consumption.

[0003] For hydrogen production via solid oxide ammonia electrolysis, the required external voltage is much lower than that required for hydrogen production via water electrolysis. Solid oxide electrolysis technology includes two categories: oxygen ion conductor type and proton conductor type. Among them, proton conductor type ammonia oxide electrolysis (NH3-PCEC) has the advantages of low reaction temperature, no need for external water vapor, and hydrogen source from NH3. Currently, NH3-PCEC is still a new technology in the laboratory stage and has great potential for development.

[0004] The existing technology has problems or needs improvement in the following areas: 1. In the NH3-PCEC, hydrogen ions are generated at the anode three-phase interface, transported by the electrolyte, and reduced to hydrogen gas at the cathode. This electrolyzer can produce hydrogen in one step under this operating mode; therefore, obtaining a large amount of hydrogen gas at the cathode is the primary objective of the NH3-PCEC.

[0005] 2. The NH3-PCEC operates at temperatures between 400-700 ℃. Since the feedstock is NH3, ammonia pyrolysis is unavoidable at the anode. This causes hydrogen atoms generated at the anode active sites to fail to enter the electrolyte transport channels and instead directly convert into hydrogen gas and escape. The hydrogen gas produced at the anode is mixed with ammonia and nitrogen and cannot be directly utilized. Therefore, reducing the anode hydrogen production capacity can effectively improve the utilization rate of anode hydrogen atoms and enhance the selectivity of hydrogen products.

[0006] 3. NH3-PCEC exhibits different unique modes, including coexistence of power generation and hydrogen production, no power consumption and no power generation, and power consumption. The applied voltage generates energy consumption. Therefore, reducing electrolysis energy consumption and improving operating efficiency are important improvement measures for controlling the cost of NH3-PCEC. Summary of the Invention

[0007] In view of this, the purpose of this invention is to provide an optimization method for solid oxide ammonia electrolyzers that improves the hydrogen production capacity of the cathode, so as to solve the problems of severe hydrogen loss at the anode, low hydrogen production efficiency at the cathode, and high electrolysis energy consumption in the existing proton conductor type solid oxide ammonia electrolysis process, and to achieve improved hydrogen product selectivity and optimized operating efficiency.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: an optimization method for a solid oxide ammonia electrolyzer to improve the hydrogen production capacity of the cathode, comprising constructing a basic reaction model of a proton conductor type solid oxide ammonia electrolyzer, verifying the basic reaction model through experimental data, and optimizing and controlling the operating parameters and / or material properties of the electrolyzer based on the verified basic reaction model to improve the hydrogen production capacity and operating efficiency of the cathode; the optimization and control includes at least one of the following methods: reducing the hydrogen adsorption and desorption rate of the anode material; improving the charge transfer reaction capability of the anode material; increasing the cathode thickness; improving the ionic conductivity of the electrolyte; improving the charge transfer reaction capability of the cathode material; and optimizing the hydrogen adsorption and desorption capability of the cathode material.

[0009] In a preferred embodiment, reducing the hydrogen adsorption-desorption rate of the anode material specifically involves selecting a material with weak hydrogen adsorption-desorption capacity as the anode, so that the adsorbed hydrogen generated after the ammonia reaction is directly used for the anode electrochemical reaction, thereby reducing the desorption of adsorbed hydrogen into hydrogen gas that escapes from the anode.

[0010] In a preferred embodiment, the improvement of the charge transfer reaction capability of the anode material specifically involves: increasing the reaction rate of the anode charge transfer reaction to promote the demand for adsorbed hydrogen in the electrochemical region, increasing the proton flux, and thereby improving the hydrogen evolution rate of the cathode.

[0011] In a preferred embodiment, increasing the cathode thickness specifically means increasing the cathode thickness to exceed the initial thickness, thereby increasing the total number of cathode active sites and the total area of ​​the three-phase interface, and thus improving the cathode hydrogen production.

[0012] In a preferred embodiment, the improvement of the ionic conductivity of the electrolyte specifically involves: enhancing the electrolyte's ability to conduct protons, enabling protons to be rapidly transferred to the cathode after generation at the anode, reducing the anodic polarization overpotential, and ensuring that protons are uniformly transported to all parts of the cathode interface, thereby reducing concentration polarization.

[0013] In a preferred embodiment, improving the charge transfer reactivity of the cathode material specifically involves selecting a cathode material with strong charge transfer capability to reduce the overpotential of the cathode hydrogen evolution reaction and achieve efficient hydrogen production at a lower cell voltage.

[0014] In a preferred embodiment, the optimization of the hydrogen adsorption-desorption capacity of the cathode material specifically involves selecting a cathode material with moderate hydrogen adsorption-desorption energy, enabling hydrogen atoms to rapidly form, combine, and release at the active sites, thereby reducing the additional overpotential caused by slow desorption.

[0015] In a preferred embodiment, the construction of the elementary reaction model includes: simplifying the electrolytic cell into a one-dimensional elementary reaction model, setting boundary conditions, describing the gas diffusion behavior according to Fick's law in the mass transfer module, establishing the microscopic kinetic equations for surface adsorption and catalytic reactions in the chemical reaction module, and using a secondary current distribution model to describe the charge transfer process in the electrochemical module.

[0016] In a preferred embodiment, the elementary reaction model is verified by experimental data, specifically by adjusting the charge transfer coefficient, exchange current density, and parameters related to the charge transfer reaction and the ammonia decomposition reaction, so that the simulation results match the experimental data, and ensuring that the correlation between the exchange current density and the parameters related to the ammonia decomposition reaction and temperature conforms to the Arrhenius equation.

[0017] In a preferred embodiment, the optimization control includes: reducing the anodic hydrogen adsorption-desorption rate at the anode near the electrolyte interface to a specific proportion of the initial value; or increasing the anodic charge transfer reaction rate at the anode near the electrolyte interface by a specific factor; or increasing the cathode thickness to a specific proportion of the initial thickness; or increasing the ionic conductivity of the electrolyte by a specific factor; or increasing the cathode charge transfer reaction rate at the cathode near the electrolyte interface by a specific factor.

[0018] Compared with the prior art, the present invention has the following beneficial effects: (1) Improve the selectivity of hydrogen products: By reducing the hydrogen adsorption and desorption rate at the anode or improving the charge transfer reaction capability at the anode, the direct escape of hydrogen on the anode side can be effectively reduced, allowing more hydrogen elements to be transported to the cathode in the form of protons through the electrolyte, thereby improving the one-step hydrogen production capability.

[0019] (2) Significantly improve the hydrogen production capacity of the cathode: By increasing the cathode thickness, improving the electrolyte ion conductivity, optimizing the cathode charge transfer capacity and hydrogen adsorption and desorption capacity, the hydrogen evolution efficiency and yield of the cathode can be improved in a synergistic way.

[0020] (3) Reduce electrolysis energy consumption and improve operating efficiency: By reducing the anodic polarization overpotential, cathode overpotential and concentration polarization, a higher current density can be achieved at a lower cell voltage, which can effectively improve electrolysis efficiency.

[0021] (4) Provides a systematic optimization method: This invention combines numerical simulation and experimental verification to establish an elementary reaction model, which can systematically evaluate the impact of different optimization strategies on the performance of the electrolytic cell, providing a scientific basis and quantifiable optimization path for the design and development of high-performance proton conductor solid oxide ammonia electrolytic cells. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the proton conductor type solid oxide ammonia electrolysis experimental apparatus in an embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of the structure of the one-dimensional elementary reaction model established in an embodiment of the present invention.

[0024] Figure 3 This is a comparison chart of model calibration results and experimental data in an embodiment of the present invention.

[0025] Figure 4 The figure shows the simulation results of the effect of the anodic hydrogen adsorption-desorption rate on hydrogen production performance in an embodiment of the present invention.

[0026] Figure 5 The figure shows the simulation results of the effect of the anodic charge transfer reaction rate on hydrogen production performance in an embodiment of the present invention.

[0027] Figure 6 The figure shows the simulation results of the effect of the cathode charge transfer reaction rate on hydrogen production performance in an embodiment of the present invention.

[0028] Figure 7 This is a simulation result diagram showing the effect of cathode thickness on hydrogen production performance in an embodiment of the present invention. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0030] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0031] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application; as used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise; furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0032] An optimization method for solid oxide ammonia electrolyzers to improve cathode hydrogen production capacity, referenced Figure 1-7 The process includes constructing a basic reaction model for a proton-conducting solid oxide ammonia electrolyzer, validating the basic reaction model using experimental data, and optimizing and controlling the operating parameters and / or material properties of the electrolyzer based on the validated basic reaction model to improve the cathode hydrogen production capacity and operating efficiency. The optimization and control includes at least one of the following methods: reducing the hydrogen adsorption / desorption rate of the anode material; improving the charge transfer reaction capability of the anode material; increasing the cathode thickness; improving the ionic conductivity of the electrolyte; improving the charge transfer reaction capability of the cathode material; and optimizing the hydrogen adsorption / desorption capability of the cathode material.

[0033] The optimized control method specifically includes: 1. Reduce the hydrogen adsorption / desorption rate at the anode by selecting an anode material with weaker hydrogen adsorption / desorption capacity. Anode ammonia oxidation involves both direct and indirect mechanisms, with the anode ammonia-related reactions following a stepwise dehydrogenation mechanism. When the hydrogen adsorption / desorption rate is reduced, a large proportion of the adsorbed hydrogen produced after the stepwise ammonia reaction is directly used in the anode electrochemical reaction, with very little adsorbed hydrogen desorbed into hydrogen gas. This almost transforms into a direct ammonia oxidation mechanism, reducing anode hydrogen escape while still providing sufficient hydrogen to meet electrochemical demands; therefore, the cathode hydrogen production capacity is not reduced. Thus, anode materials with weaker hydrogen adsorption / desorption capacity can be selected.

[0034] 2. Enhance the anodic charge transfer reaction capability. Adsorbed hydrogen is a reactant in the anodic charge transfer reaction. Increasing the reaction rate promotes the demand for adsorbed hydrogen in the electrochemical region, encouraging hydrogen to exist in its adsorbed form rather than as a gas. This not only drives the upstream ammonia-related reactions, allowing their gradual dehydrogenation rate to keep pace with the anodic hydroxide reaction, but also increases the proton flux to the cathode-electrolyte three-phase interface, thereby increasing the final hydrogen evolution rate at the cathode. 3. Increase the cathode thickness to a certain extent. The cathode, which is currently relatively thin, is increased by a certain amount. The cathode is where more hydrogen is produced; therefore, an electron-ion hybrid conductor is used as the cathode material. Increasing the cathode thickness linearly increases the total number of active cathodes and the total area of ​​the three-phase interface, which almost linearly increases the hydrogen production concentration at the cathode. At the same time, it is important to avoid excessive cathode thickness, which would increase the total cathode impedance, prevent areas from where electrochemical reactions do not occur, resulting in lower hydrogen evolution efficiency and material waste.

[0035] 4. Improve the ionic conductivity of the electrolyte. The electrolyte is an intermediate substance between the two electrodes. For the anode, high ionic conductivity of the electrolyte means that once protons are generated at the anode three-phase interface, they can be rapidly transferred and transported to the cathode. This avoids the accumulation of protons at the reaction interface, reduces the proton chemical potential, increases the driving force for the dissociation of ammonia molecules to generate protons, and makes it easier for the anode reaction equilibrium to move to the right, significantly reducing the anode polarization overpotential. This allows the electrolysis reaction to reach the target current at a lower cell voltage, improving energy efficiency. The cathode is generally a mixture of cathode catalyst and electrolyte material sintered together. For the cathode, high electrolyte ionic conductivity ensures that protons can be rapidly and uniformly transported from the entire electrolyte to all parts of the cathode interface. This avoids certain areas of the cathode interface from failing to react due to insufficient proton supply, ensuring the effective utilization of the entire cathode area, making the hydrogen generation reaction uniformly distributed, and improving the effective area ratio of the single cell. Maintaining a high hydrogen production rate at the cathode, while the rapid consumption and replenishment of protons maintains the relative stability of the proton concentration at the cathode interface, significantly reducing cathode concentration polarization caused by proton transport limitations.

[0036] 5. Enhance the charge transfer capability of the cathode. During electrolysis, the cathode material needs to possess strong charge transfer capability, primarily to efficiently reduce the overpotential of the hydrogen evolution reaction and improve overall energy efficiency. The Volmer step of hydrogen evolution at the cathode—the combination of protons and electrons to form adsorbed hydrogen atoms—has a high energy barrier if the charge transfer capability is weak, requiring a higher voltage and resulting in energy waste. Simultaneously, ammonia oxidation occurs at the anode, and its overpotential is usually not low. If the cathode also requires a high voltage, the total system voltage will increase significantly, and energy efficiency will drop sharply. Therefore, selecting a cathode material with strong charge transfer capability can greatly promote the rapid transfer of electrons to the interface, reducing the cathode overpotential, thereby achieving efficient hydrogen production at a lower cell voltage, and synergistically reducing the total energy consumption of the entire electrolyzer in conjunction with the anode process.

[0037] 6. Optimize the hydrogen adsorption and desorption capacity of the cathode. In the electrolytic hydrogen production process, improving the hydrogen adsorption and desorption capacity of the cathode material is crucial. Ideally, the material should possess "moderate" hydrogen adsorption and desorption energy: if adsorption is too strong, the generated hydrogen atoms will remain excessively on the surface, poisoning the active sites and hindering subsequent reactions; if desorption is too weak, hydrogen atoms will have difficulty effectively combining to form hydrogen molecules. Therefore, optimizing the adsorption and desorption capacity aims to enable hydrogen atoms to "form rapidly, combine rapidly, and release rapidly" at the active sites, efficiently clearing the reaction pathway and reducing the additional overpotential caused by slow desorption, thereby achieving stable hydrogen production with high current density at lower energy consumption.

[0038] This example provides the experimental testing process, model establishment, and optimization scheme obtained from the prediction of a proton conductor-type solid ammonia oxidant electrolysis experiment at 550 ℃.

[0039] refer to Figure 1 The experimental setup specifically includes: a first pressure reducing valve 2, a first flow meter 3, a second pressure reducing valve 5, a second flow meter 6, a reactor 7, a heating furnace 8, a desiccant 9, a soap film flow meter 10, a gas chromatograph 11, a tail gas collection unit 12, an electrochemical workstation 13, and a battery cell 14; the first pressure reducing valve 2 is connected to the first flow meter 3, and the second pressure reducing valve 5 is connected to the second flow meter 6; the first flow meter 3 and the second flow meter 6 are connected to the reactor 7; the reactor 7 is located inside the heating furnace 8, and the battery cell 14 is placed inside the reactor 7; During the experiment, H2 / NH3 was introduced into the anode inlet 1, passed through the first pressure reducing valve 2, and entered the reactor 7 under the control of the first flow meter 3. Ar was introduced into the cathode inlet 4, passed through the second pressure reducing valve 5, and entered the reactor 7 under the control of the second flow meter 6. The cathode side of the solar cell 14 was at the bottom, and the anode side of the solar cell 14 was at the top, and they were fixed with ceramic adhesive. The reactor 7 was heated in the heating furnace 8. The experimental data were obtained using an electrochemical workstation 13 when testing the gas flow performance. The tail gas was collected at the anode outlet 12, and the cathode outlet passed through a desiccant 9 and a soap film flow meter 10. The hydrogen production was tested using a gas chromatograph 11.

[0040] During this experiment, the reaction occurring at the anode is as follows:

[0041] The reaction that occurs at the cathode is:

[0042] A model is established, with the following assumptions: the gas involved in the reaction is assumed to be an ideal gas; the mixed ion-electron conductor and ion conductor in the electrode are uniformly and continuously distributed; and the effects of gas phase reaction, gas flow and heat transfer are ignored.

[0043] refer to Figure 2Based on the model assumptions, the battery is simplified into a one-dimensional elementary reaction model, including anode 21, electrolyte 22 and cathode 23, including mass transfer within the anode channel, charge transfer reaction at the anode-electrolyte interface, electron-ion current density distribution inside the battery and cathode reaction.

[0044] Boundary condition settings: Based on the principle of charge conservation, ion transport boundaries exist in the model. The anode surface and the outer surface of the cathode are set as insulating boundaries, while the anode / electrolyte interface and the electrolyte / cathode interface are set as continuous boundaries. Based on the principle of electron charge conservation, the anode surface is set as a zero potential reference, and a working voltage is applied to the outer surface of the cathode.

[0045] In the mass transfer module, a custom control equation is used to describe the gas diffusion behavior in the electrode region according to Fick's law. The simulated components of the anode include NH3, H2, and N2, while the components of the cathode include H2 and Ar.

[0046] Surface reaction kinetics and electrochemical reaction model equations were established: In the chemical reaction module, microscopic kinetic equations for surface adsorption and catalytic reactions were established in the anodic region. The reaction rate constants adopted the Arrhenius equation form, and the kinetic parameters were obtained from a professional database. The elementary reactions at the anodic region included ammonia adsorption-desorption, ammonia stepwise dehydrogenation, hydrogen adsorption-desorption, nitrogen adsorption-desorption, and charge transfer reactions. In the electrochemical module, a secondary current distribution model was used to describe the charge transfer process at the three-phase interface through a hydrogen overflow mechanism.

[0047] Initial model parameter settings: temperature 550℃, pressure 101.325kPa (standard atmospheric pressure), anode inlet gas 100% NH3, cathode inlet gas 100% Ar, gas diffusion coefficient calculated by the software's built-in database, and other physical property parameters obtained through experimental testing and literature review.

[0048] The simulation results are made to match the experimental data by adjusting the following key parameters: the charge transfer coefficients alpha_an and alpha_ca related to the charge transfer reaction, the exchange current densities i0_an and i0_ca, and β related to the ammonia decomposition reaction. When satisfactory agreement is achieved between the experimental and model results, the model validation at that temperature point is complete. It is important to ensure that the correlation between i0 and β and temperature conforms to the Arrhenius equation. If the validation results do not conform to this mathematical relationship, the entire validation process must be repeated. This process involves calibrating the model's IV curve through charge transfer reaction kinetics and ammonia decomposition reaction kinetics. For the calibrated and validated model, parameter adjustment is performed, and the results are quantified to obtain a clear optimization scheme: 1) When the applied voltage is 0.6 V, the anodic hydrogen adsorption-desorption rate (R1) near the electrolyte interface is: The rate was reduced to the initial 3 × 10 -8 At this point, the anode hydrogen production capacity decreased by 99% compared to the original situation, while the cathode hydrogen production maintained its upward trend and even increased by 5%. (690 mA / cm) 2 Efficiency increased from 75% to 76%.

[0049] 2) At an applied voltage of 0.6 V, the anodic charge transfer reaction rate (CTR, an) near the electrolyte interface is: This increases the rate tenfold, to 690 mA / cm². 2 The efficiency increased from 75% to 80%, with anode hydrogen production decreasing by 4% and cathode hydrogen production increasing by 35%. The anode charge transfer reaction rate increased 100-fold, with anode hydrogen production decreasing by 7% and cathode hydrogen production increasing by 71%. 690 mA / cm² 2 Efficiency increased from 75% to 84%.

[0050] 3) As the cathode thickness increased from 7 μm to 17 μm, hydrogen production at the anode decreased by only 0.5%, while hydrogen production at the cathode increased. 179%. 690mA / cm 2 Efficiency increased from 75% to 76%.

[0051] 4) The ionic conductivity of the electrolyte is After a 10-fold increase, anode hydrogen production decreased by 15%, while cathode hydrogen production increased by 177%. 690 mA / cm² 2 Efficiency increased from 75% to 83%.

[0052] 5) At an applied voltage of 0.6 V, the cathodic charge transfer reaction rate (CTR,ca) near the cathode electrolyte interface is: After a 10-fold increase, anode hydrogen production decreased by 3%, while cathode hydrogen production increased by 22%. 690 mA / cm² 2 Efficiency increased from 75% to 79%.

Claims

1. An optimization method for a solid oxide ammonia electrolyzer to improve the cathode hydrogen production capacity, characterized in that, The method includes constructing a basic reaction model for a proton-conducting solid oxide ammonia electrolyzer, validating the basic reaction model through experimental data, and optimizing and controlling the operating parameters and / or material properties of the electrolyzer based on the validated basic reaction model to improve the cathode hydrogen production capacity and operating efficiency. The optimization and control includes at least one of the following methods: reducing the hydrogen adsorption and desorption rate of the anode material; improving the charge transfer reaction capability of the anode material; and increasing the cathode thickness. Improve the ionic conductivity of the electrolyte; enhance the charge transfer reaction capability of the cathode material; optimize the hydrogen adsorption and desorption capability of the cathode material.

2. The method for optimizing a solid oxide ammonia electrolyzer to improve cathode hydrogen production capacity according to claim 1, characterized in that, The method to reduce the hydrogen adsorption and desorption rate of the anode material is as follows: select a material with weak hydrogen adsorption and desorption capacity as the anode, so that the adsorbed hydrogen generated after the ammonia reaction is directly used for the anode electrochemical reaction, thereby reducing the desorption of adsorbed hydrogen into hydrogen gas that escapes from the anode.

3. The method for optimizing a solid oxide ammonia electrolyzer to improve cathode hydrogen production capacity according to claim 1, characterized in that, The improvement of the charge transfer reaction capability of the anode material specifically involves: increasing the reaction rate of the anode charge transfer reaction to promote the demand for adsorbed hydrogen in the electrochemical region, increasing the proton flux, and thereby improving the hydrogen evolution rate of the cathode.

4. The method for optimizing a solid oxide ammonia electrolyzer to improve cathode hydrogen production capacity according to claim 1, characterized in that, The increase in cathode thickness specifically refers to increasing the cathode thickness beyond the initial thickness to increase the total number of cathode active sites and the total area of ​​the three-phase interface, thereby increasing the cathode hydrogen production.

5. The method for optimizing a solid oxide ammonia electrolyzer to improve cathode hydrogen production capacity according to claim 1, characterized in that, The improvement of the ionic conductivity of the electrolyte specifically involves: enhancing the electrolyte's ability to conduct protons, enabling protons to be rapidly transferred to the cathode after generation at the anode, reducing the anodic polarization overpotential, and ensuring that protons are uniformly transported to all parts of the cathode interface, thereby reducing concentration polarization.

6. The method for optimizing a solid oxide ammonia electrolyzer to improve cathode hydrogen production capacity according to claim 1, characterized in that, The improvement of the charge transfer reaction capability of the cathode material specifically involves selecting a cathode material with strong charge transfer capability to reduce the overpotential of the cathode hydrogen evolution reaction and achieve efficient hydrogen production at a lower cell voltage.

7. The method for optimizing a solid oxide ammonia electrolyzer to improve cathode hydrogen production capacity according to claim 1, characterized in that, The optimization of the hydrogen adsorption and desorption capacity of the cathode material specifically involves selecting a cathode material with moderate hydrogen adsorption and desorption capacity, enabling hydrogen atoms to rapidly form, combine, and release at the active sites, thereby reducing the additional overpotential caused by slow desorption.

8. The method for optimizing a solid oxide ammonia electrolyzer to improve cathode hydrogen production capacity according to claim 1, characterized in that, The construction of the elementary reaction model includes: simplifying the electrolytic cell into a one-dimensional elementary reaction model, setting boundary conditions, describing gas diffusion behavior according to Fick's law in the mass transfer module, establishing microscopic kinetic equations for surface adsorption and catalytic reactions in the chemical reaction module, and using a secondary current distribution model to describe the charge transfer process in the electrochemical module.

9. The method for optimizing a solid oxide ammonia electrolyzer to improve cathode hydrogen production capacity according to claim 8, characterized in that, The elementary reaction model was verified by experimental data, specifically by adjusting the charge transfer coefficient, exchange current density, and parameters related to the charge transfer reaction and the ammonia decomposition reaction, so that the simulation results matched the experimental data, and ensuring that the correlation between the exchange current density and the parameters related to the ammonia decomposition reaction and temperature conformed to the Arrhenius equation.

10. The method for optimizing a solid oxide ammonia electrolyzer to improve cathode hydrogen production capacity according to claim 1, characterized in that, The optimization control includes: reducing the anodic hydrogen adsorption-desorption rate at the anode near the electrolyte interface to a specific proportion of the initial value; or increasing the anodic charge transfer reaction rate at the anode near the electrolyte interface by a specific factor; or increasing the cathode thickness to a specific proportion of the initial thickness; or increasing the ionic conductivity of the electrolyte by a specific factor; or increasing the cathode charge transfer reaction rate at the cathode near the electrolyte interface by a specific factor.

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