A misfit-loaded praseodymium-based anode catalyst for direct ammonia solid oxide fuel cells and a preparation method thereof

Abstract

The application belongs to the field of preparation of anode catalysts for solid oxide direct ammonia fuel cells, and particularly relates to a misfit-loaded praseodymium-based anode catalyst for direct ammonia solid oxide fuel cells and a preparation method thereof. 2+ doping Pr2NiO4 to prepare a perovskite Pr2Ni 1‑x Zn x O4 precursor, which is subjected to in-situ precipitation of Ni under a reducing atmosphere, is anchored on the catalyst surface in the form of an element, and is converted into Pr2O3 with the destruction of the structure of the precursor, and Zn 2+ with a high segregation Gibbs free energy is retained in the Pr2O3 lattice, realizing the rearrangement of each element, and forming a misfit-loaded Ni / Pr 2‑x Zn x O3 (PNZx), 0

Description

Technical Field

[0001] The present invention belongs to the field of preparation of anode catalysts for direct ammonia solid oxide fuel cells, and in particular relates to the preparation and application of a dislocation-supported praseodymium-based anode catalyst for direct ammonia solid oxide fuel cells. Background Art

[0002] A solid oxide fuel cell (SOFC) is a device that can directly and efficiently convert chemical energy into electrical energy, unconstrained by the Carnot cycle and boasting energy conversion efficiencies as high as 60-80%. An SOFC is a concentration cell, utilizing the chemical potential difference between the fuel and air electrodes to generate an open-circuit voltage, thereby driving external circuit components. A SOFC employs a solid-state "sandwich" structure consisting of an anode layer, an electrolyte layer, and a cathode layer. This structure avoids the leakage problems common in liquid-phase batteries and is therefore safer and more stable. Traditionally, research on anode materials has focused on nickel-based perovskite oxides, which offer excellent fuel conversion efficiency. However, nickel-based perovskite oxides are prone to coarsening and agglomeration under high-temperature operating conditions, which reduces the cycle life of the fuel cell. Current research on anode materials focuses on exposing more surface active sites, improving fuel conversion efficiency, and enhancing the stability of nickel-based materials. A common approach involves in-situ precipitation of nickel-based anode perovskite materials. In-situ precipitation involves the in-situ formation of nanoparticles of readily reducible elements such as Ni, Co, and Fe on the anode surface under a reducing atmosphere. Surface nanoparticles provide more active sites for catalytic reactions. This strategy can reduce polarization resistance and improve output density, surface conductivity, stability, and catalytic performance. The MPD of traditional NiO-based anodes in H₂ is much higher than that in NH₃. This is primarily due to two factors: first, the slow kinetics of N₂ dissociative adsorption. Second, the intermediate H₂ produced by NH₃ decomposition competes with NH₃ for active sites, a phenomenon known as the "hydrogen poisoning" effect. Traditional perovskite anode materials are often synthesized using high-temperature solid-phase methods or coprecipitation methods. The high-temperature solid-phase method has a long synthesis cycle and high synthesis temperature, resulting in low powder purity. While the coprecipitation method is simpler to synthesize, it produces larger powders. The sol-gel method uses inorganic or metal alkoxide precursors, uniformly mixing these raw materials in a liquid phase and subjecting them to hydrolysis and condensation reactions. This forms a stable, transparent sol system in solution. Upon aging, the colloidal particles slowly aggregate, forming a gel with a three-dimensional network structure. The gel network is filled with solvent, which has lost its fluidity, forming a gel. The gel is dried, sintered and solidified to produce molecular and even sub-nanostructured materials.

[0003] CN115377430A discloses a highly active and durable direct ammonia solid oxide fuel cell anode and its preparation method.2-δ Nanoparticles are loaded on the Ni-YSZ anode of a direct ammonia solid oxide fuel cell, which greatly improves the ammonia catalytic decomposition activity and stability of the Ni-YSZ anode and has a low cost, but its power density still needs to be improved.

[0004] CN115621473A discloses a solid oxide fuel cell anode material, its preparation method, and its application. The outer layer comprises Ni-Fe alloy particles formed by in-situ exsolution. While this anode material possesses a three-dimensional ordered macroporous structure, its long-term stability and carrier purity require further improvement.

[0005] CN113889629A discloses a method for preparing a platinum-ruthenium alloy catalyst for a fuel cell anode. The anode material has a high power density, but its noble metal content is high and the manufacturing cost is high.

[0006] CN113299933A discloses a method for preparing a non-precious metal direct methanol fuel cell anode catalyst. The anode is made by mixing Cu-BTC and Ni-MOF, which improves the catalytic activity of the direct methanol fuel cell catalyst. However, the preparation method is complex and difficult to industrialize.

[0007] CN113178587A discloses a solid oxide fuel cell anode material, its preparation method, and application. The anode loads Cu and Ni onto LSCM, and the preparation process is simple, but its power density and long-term stability need to be improved.

[0008] The above reports have problems that need to be solved urgently, such as insufficient power density of anode materials, expensive synthetic materials, complex synthesis process, and poor cycle stability. Summary of the Invention

[0009] The purpose of this invention is to address the shortcomings of the existing technology and provide a staggered supported praseodymium-based anode catalyst for direct ammonia solid oxide fuel cells and its preparation method, so as to achieve a solid oxide direct ammonia fuel cell anode with high catalytic activity, high ammonia utilization rate and good stability for ammonia fuel gas. 2- x Zn x O3, 0≤x≤0.15 anode material, its preparation method is simple, energy consumption is low, and Ni can be precipitated in situ under reducing atmosphere, thereby improving catalytic activity and regulating ammonia utilization rate. 2-x Zn x O3 is used as the anode of solid oxide direct ammonia fuel cells. Under conditions simulating pure ammonia, the output power density of hydrogen fuel SOFC is similar to that of ammonia fuel SOFC. It is an anode catalyst for solid oxide direct ammonia fuel cells suitable for large-scale promotion and application.

[0010] To achieve the above object, the present invention adopts the following technical solutions:

[0011] A dislocation-supported praseodymium-based anode catalyst for a direct ammonia solid oxide fuel cell, wherein the chemical formula of the praseodymium-based anode catalyst is Ni / Pr 2-x Zn x O3, 0≤x≤0.15.

[0012] A method for preparing a dislocation-supported praseodymium-based anode catalyst for a direct ammonia solid oxide fuel cell comprises the following steps:

[0013] (1) Precursor Pr2Ni 1-x Zn x Synthesis of O4 oxide

[0014] According to stoichiometric requirements, weigh 8.71 g of praseodymium nitrate hexahydrate and 2.52-2.97 g of nickel salt into a beaker. Pour in 250 ml of water to dissolve. Stir the solution for 50-70 minutes. This is referred to as Solution A. In Solution A, maintain a molar ratio of total metal ions to complexing agent of 1:1-2. According to stoichiometric requirements, weigh 0-0.45 g of zinc salt into a beaker and dissolve in 50 ml of water and 10-20 ml of aqueous ammonia. Once the solution is completely dissolved, add 10-20 ml of surfactant. This is referred to as Solution B. After the solution is prepared, adjust the speed of the magnetic stirrer to 200-700r / min, quickly pour solution A into solution B, continue stirring for 3-6 hours, stop stirring, put it in a water bath, keep the temperature at 70-100℃, maintain for 4-6 hours, wait until the solvent evaporates completely and the solution becomes a transparent gel, stop heating and stirring, then put the gel into an oven, set the temperature to 180-220℃, maintain for 12-24 hours, cool, grind, and calcine to obtain Pr2Ni 1-x Zn x O4, 0≤x≤0.15 perovskite precursor.

[0015] (2) Dislocation load Ni / Pr 2-x Zn x O3(PNZx), 0≤x≤0.15, synthesis of catalyst

[0016] Pr2Ni 1-x Zn x O4, 0≤x≤0.15 perovskite precursor was reduced in a reducing atmosphere to obtain dislocation-loaded Ni / Pr 2-x Zn x O3 catalyst.

[0017] (3) Preparation of anode slurry

[0018] First, a viscosifier solution containing a thickener at a mass fraction of 4% to 10% is prepared: the thickener and the viscosifier are mixed in a mass ratio of (4-10): (96-90), and heated in a water bath at a temperature of 40-80°C. When the viscosifier becomes clear and transparent, the water bath is removed, and the solution is cooled and refrigerated in a refrigerator at a temperature of 0-5°C.

[0019] Then, Pr2Ni 1-x Zn x O4 perovskite precursor and 8% mol Y2O3 stabilized ZrO2 (YSZ) (purchased from Ningbo Suofer Energy Technology Co., Ltd.)

[0020] Mix according to the mass ratio of (4-6): (6-4), grind for 20-60 minutes, slowly add 4-8 drops of thickener solution, and continue grinding for 20-40 minutes to obtain pretreated anode slurry. 1-x Zn x The reduction process of the O4 perovskite precursor is carried out after the battery materials are assembled, and the PNZx anode material is obtained at the SOFC device.

[0021] Furthermore, the nickel salt in step (1) is one or more of nickel chloride hexahydrate, nickel nitrate hexahydrate, nickel acetate, and nickel sulfate.

[0022] Furthermore, the zinc salt in step (1) is one or more of zinc chloride, zinc nitrate hexahydrate, and zinc acetate.

[0023] Furthermore, the complexing agent in step (1) is one or more of citric acid, oxalic acid, salicylic acid, tartaric acid, amino acid, and ethylenediaminetetraacetic acid.

[0024] Furthermore, the surfactant in step (1) is one or more of ammonium citrate, ethylenediamine, ethylene glycol, and polyethylene glycol.

[0025] Furthermore, the calcination process in step (1) is: pre-calcination at 600-800°C for 4-8 hours, maintaining the heating rate at 1-10°C / min, and then calcination at 1200°C for 2-5 hours, maintaining the heating rate at 2-5°C / min.

[0026] Furthermore, the reduction process in step (2) is as follows: introducing 10 vol%-50 vol% hydrogen / argon mixed gas into a tube furnace and reducing at 800-1000° C. for 2-10 hours.

[0027] Furthermore, the thickener in step (3) is one of ethyl cellulose, hydroxyethyl cellulose, methyl cellulose, guar gum, hydroxypropyl methyl cellulose, and polyacrylamide.

[0028] Furthermore, the thickening agent in step (3) is one or more of turpentine alcohol, terpineol, neroli oil, orange leaf oil, camphor oil, and lemon oil.

[0029] Application: The praseodymium-based anode catalyst is used as an anode material for direct ammonia solid oxide fuel cells.

[0030] The significant advantages of the present invention are:

[0031] Select Zn 2+ Doping Pr2NiO4 to prepare Pr2Ni 1-x Zn x O4 precursor, which precipitates Ni in situ under reducing atmosphere and is anchored on the catalyst surface in the form of a single substance, and is converted into Pr2O3 along with the destruction of the precursor structure, while Zn with high segregation Gibbs free energy 2+ Retention in the Pr2O3 lattice achieves the rearrangement of the elements, forming a dislocation-loaded PNZx anode catalyst with the following advantages:

[0032] (1) Zn 2+ As a low-valent element doping, the Pr 3+ and Pr 4+ , thereby increasing the oxygen vacancy concentration;

[0033] (2) Zn 2+ The adsorption capacity of the anode catalyst to H2 is weakened, alleviating the "hydrogen poisoning" phenomenon;

[0034] (3) Ni nanoparticles provide sufficient electron transport for the reaction on the anode surface, while Pr 2-x Zn x The abundant oxygen vacancies of O3 ensure sufficient oxygen transport, which makes the anode PNZ0.1 have high electrocatalytic activity. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Pr2Ni 1-x Zn x O4 and Ni / Pr 2-x Zn x XRD spectrum of O3(PNZx), 0≤x≤0.15 sample;

[0036] Figure 2 is the SEM image of PNZ0.1 anode catalyst;

[0037] Figure 3 Pr2Ni 1-x Zn x O4 and Ni / Pr 2-x Zn xFT-IR spectrum of O3(PNZx), 0≤x≤0.15 sample. DETAILED DESCRIPTION

[0038] The present invention is further described below with reference to examples.

[0039] Example 1

[0040] Synthesis of PNZ0.1 Oxide

[0041] (1) Precursor Pr2Ni 1.9 Zn 0.1 Synthesis of O4 oxide

[0042] According to stoichiometric requirements, 8.71 g of praseodymium nitrate hexahydrate and 2.67 g of nickel nitrate hexahydrate were weighed into a beaker and dissolved in 250 ml of water. The solution was stirred for 60 minutes, designated Solution A. The molar ratio of total metal ions to complexing agent (citric acid) in Solution A was 1:1.2. According to stoichiometric requirements, 0.30 g of zinc nitrate hexahydrate was weighed into a beaker and dissolved in 50 ml of water and 10 ml of aqueous ammonia. After complete dissolution, 10 ml of ethylene glycol was added, designated Solution B. After the solutions were prepared, the magnetic stirrer was set to 500 rpm. Solution A was rapidly poured into Solution B. Stirring was continued for 5 hours, then the stirring was stopped and the solution was placed in a water bath at 80°C for 5 hours. Once the solvent had evaporated completely and the solution formed a transparent gel, heating and stirring were stopped. The gel was then placed in an oven at 180°C for 15 hours and then cooled. Use a medicine spoon to take out the block precursor in the beaker and place it in an agate mortar to fully grind it into powder. Place the powder in a bowl and calcine it. Pre-calculate it at 600℃ for 4 hours and then calcine it at 1200℃ (heating rate maintained at 2℃ / min) for 5 hours to obtain Pr2Ni 0.9 Zn 0.1 O4 precursor powder sample.

[0043] (2) Dislocation load Ni / Pr 1.9 Zn 0.1 Synthesis of O3 catalyst

[0044] Pr2Ni 1.9 Zn 0.1 After the battery is assembled, the O4 perovskite precursor is reduced by introducing high-purity hydrogen at 800 ° C for 2 hours to obtain Ni / Pr 1.9 Zn 0.1 O3 anode material.

[0045] (3) Ni / Pr in step (2) 1.9 Zn 0.1Before pre-treating the O3 anode catalyst, a turpentine-alcohol solution containing 4% ethyl cellulose by mass must be prepared. The basic preparation process is as follows: First, weigh the ethyl cellulose and turpentine-alcohol solution in a ratio of 4:96 and place them in a beaker. Heat the mixture in a water bath maintained at 60°C. Once the turpentine-alcohol solution becomes clear and transparent, remove it from the water bath. After cooling, refrigerate the mixture at 0°C.

[0046] Pr2Ni 0.9 Zn 0.1 O4 perovskite precursor anode slurry: according to Pr2Ni 0.9 Zn 0.1 The sample was weighed and poured into an agate mortar with a mass ratio of O4:YSZ=6:4 for preliminary mixing. Then, the sample was repeatedly mixed and ground with an agate pestle for 15 minutes. The Pr2Ni 0.9 Zn 0.1 The O4 oxide and YSZ powder are mixed evenly and the grinding can be stopped when there is no obvious granularity during the grinding process. Use a 1 ml dropper to slowly add 3 drops of the prepared turpentine alcohol solution to the ground powder and continue grinding for 30 minutes to promote the full mixing of the turpentine alcohol solution and the mixed powder. When it becomes a viscous paste, the grinding can be stopped. At this time, Pr2Ni 1.9 Zn 0.1 O4 perovskite precursor anode slurry.

[0047] Product performance test:

[0048] Direct ammonia solid oxide fuel cell sheet uses YSZ with a diameter of 15mm as electrolyte, LSM-40YSZ composite slurry as cathode material, PNZ0.1-40YSZ anode through Pr2Ni 0.9 Zn 0.1 The O4-40YSZ pre-treated composite slurry was reduced at the SOFC cell end. The single cell was prepared by screen printing. The specific preparation process is as follows: First, the pre-treated anode slurry was printed on the other side of the electrolyte (diameter 10mm, effective area 0.785cm 2 ) was dried and calcined at 1200°C for 2 hours. In the same way, the cathode slurry was printed on one side of the electrolyte (diameter 5 mm, effective area 0.196 cm 2 ), dried and then calcined at 1100°C for 2 hours. After cooling, the required LSM-40YSZ|YSZ|PNZ0.1-40YSZ pre-treated single cell sheet was obtained. Before assembling the fuel cell, a thin layer of silver paste needs to be evenly screen-printed on the cathode of the single cell to serve as a current collector during testing. 0.9 Zn0.1 O4-40YSZ pretreated single cell was reduced in SOFC device to obtain LSM-40YSZ|YSZ|Ni / Pr 1.9 Zn 0.1 O3-40YSZ single battery.

[0049] The assembly of the fuel cell first places the platinum wire (0.5mm diameter, 50mm length) and the nickel mesh (15mm diameter) on the corundum tube of the test device, and then places the anode side of the single cell to be tested on the nickel mesh to ensure that the anode is in contact with the fuel gas and the cathode is in contact with the air. The middle part is sealed with a high-temperature ceramic adhesive. Finally, a silver mesh and platinum wire are added to the cathode, and the platinum wire is tightly connected to the electrode material with platinum slurry. After waiting for the ceramic adhesive to be sealed, high-purity (99.999%) ammonia is used as the fuel gas for testing. The Zahner IM6 electrochemical workstation was used for power density and impedance testing.

[0050] Example 2

[0051] The specific preparation method is basically the same as that of Example 1 in this section, except that the synthesis of PNZ0.1 oxide is changed to the synthesis of PNZ0.15 oxide, 2.67 g of nickel nitrate hexahydrate is changed to 2.52 g of nickel nitrate hexahydrate, and 0.30 g of zinc nitrate hexahydrate is changed to 0.45 g of zinc nitrate hexahydrate.

[0052] Example 3

[0053] The specific preparation method is basically the same as that of Example 1 in this section, except that the synthesis of PNZ0.1 oxide is changed to the synthesis of PNZ0.05 oxide, 2.67 g of nickel nitrate hexahydrate is changed to 2.82 g of nickel nitrate hexahydrate, and 0.30 g of zinc nitrate hexahydrate is changed to 0.15 g of zinc nitrate hexahydrate.

[0054] Example 4

[0055] The specific preparation method is basically the same as that of Example 1 of this section, except that nickel nitrate hexahydrate is replaced with nickel chloride.

[0056] Example 5

[0057] The specific preparation method is basically the same as that of Example 1 in this section, except that zinc nitrate hexahydrate is replaced by zinc chloride.

[0058] Example 6

[0059] The specific preparation method is basically the same as that of Example 1 of this section, except that citric acid is replaced with ethylenediaminetetraacetic acid.

[0060] Example 7

[0061] The specific preparation method is basically the same as Example 1 of this section, except that the molar ratio of total metal ions: complexing agent = 1:1.2 is changed to 1:1.

[0062] Example 8

[0063] The specific preparation method is basically the same as that of Example 1 of this section, except that the molar ratio of total metal ions: complexing agent = 1:1.2 is changed to 1:5.

[0064] Example 9

[0065] The specific preparation method is basically the same as that of Example 1 in this section, except that the speed of the magnetic stirrer in step (1) is changed from 500 r / min to 400 r / min, and the continuous stirring time is changed from 5 hours to 6 hours.

[0066] Example 10

[0067] The specific preparation method is basically the same as that of Example 1 in this section, except that the speed of the magnetic stirrer in step (1) is changed from 500 r / min to 700 r / min, and the continuous stirring time is changed from 5 hours to 3 hours.

[0068] Example 11

[0069] The specific preparation method is basically the same as that of Example 1 in this section, except that the setting temperature in the oven in step (1) is changed from 180°C to 200°C, and the insulation time is changed from 15 hours to 12 hours.

[0070] Example 12

[0071] The specific preparation method is basically the same as that of Example 1 in this section, except that the setting temperature in the oven in step (1) is changed from 180°C to 220°C, and the insulation time is changed from 15 hours to 20 hours.

[0072] Example 13

[0073] The specific preparation method is basically the same as that of Example 1 of this section, except that the setting temperature in the oven in step (1) is changed from 180°C to 190°C, and the insulation time is changed from 15 hours to 20 hours.

[0074] Example 14

[0075] The specific preparation method is basically the same as that of Example 1 in this section, except that the setting temperature in the oven in step (1) is changed from 180°C to 210°C, and the insulation time is changed from 15 hours to 20 hours.

[0076] Example 15

[0077] The specific preparation method is basically the same as that of Example 1 in this section, except that the speed of the magnetic stirrer in step (1) is changed from 500 r / min to 600 r / min, and the continuous stirring time is changed from 5 hours to 3 hours.

[0078] Example 16

[0079] The specific preparation method is basically the same as that of Example 1 of this section, except that ethyl cellulose is replaced by hydroxyethyl cellulose.

[0080] Example 17

[0081] The specific preparation method is basically the same as that of Example 1 of this section, except that ethyl cellulose is replaced by methyl cellulose.

[0082] Example 18

[0083] The specific preparation method is basically the same as that of Example 1 of this section, except that ethyl cellulose is replaced by hydroxypropyl methylcellulose.

[0084] Example 19

[0085] The specific preparation method is basically the same as that of Example 1 of this section, except that ethyl cellulose is replaced by polyacrylamide.

[0086] Example 20

[0087] The specific preparation method is basically the same as that of Example 1 of this section, except that turpentine alcohol is replaced with terpineol.

[0088] Comparative Example 1

[0089] (1) Synthesis of precursor Pr2NiO4 oxide

[0090] According to stoichiometric requirements, 8.71 g of praseodymium nitrate hexahydrate and 2.96 g of nickel nitrate hexahydrate were weighed into a beaker and dissolved in 250 ml of water. The solution was stirred for 60 minutes, designated Solution A. The molar ratio of total metal ions to complexing agent (citric acid) in Solution A was 1:1.2. In another beaker, 50 ml of water and 10 ml of ammonia were added to dissolve the ions. After complete dissolution, 10 ml of ethylene glycol was added, designated Solution B. After the solutions were prepared, the magnetic stirrer was set to 500 rpm. Solution A was rapidly poured into Solution B. Stirring was continued for 5 hours, then the stirring was stopped and the solution was placed in a water bath at 80°C for 5 hours. Once the solvent had evaporated completely and the solution formed a transparent gel, heating and stirring were stopped. The gel was then placed in an oven at 180°C for 15 hours before being removed and cooled. Use a medicine spoon to take out the block precursor in the beaker and place it in an agate mortar to fully grind it into powder. Place the precursor powder in a dish for calcination. The calcination process is pre-calcination at 600°C for 4 hours, then calcination at 1200°C for 5 hours, and the heating rate is maintained at 2°C / min to obtain the Pr2NiO4 perovskite precursor powder sample.

[0091] (2) Synthesis of dislocation-supported Ni / Pr2O3 catalyst

[0092] After assembling the battery, the reduction process of the Pr2NiO4 perovskite precursor is to introduce high-purity hydrogen and reduce it at 800°C for 2 hours to obtain Ni / Pr2O3 anode material.

[0093] Comparative Example 2

[0094] The specific preparation method is basically the same as that of Example 1 in this section, except that the anode catalyst is replaced with commercial NiO powder.

[0095] Table 1 Current density and power density of direct ammonia solid oxide fuel cell at 800℃.

[0096]

[0097]

[0098] for Figure 1 Figure A in the figure is Pr2Ni 1-x Zn x O4 precursor perovskite, XRD spectrum shows that Pr2Ni 1-x Zn x The O4 perovskite precursor structure was successfully synthesized. Figure 1 Figure B in the figure is Pr2Ni 1-x Zn xThe XRD spectrum of O4 reduced in a reducing atmosphere shows that the main phase changes from perovskite to praseodymium trioxide, and the crystal planes before and after reduction shift, indicating that Zn is incorporated into the crystal structures of both. Figure 2 Pr2Ni 1-x Zn x The SEM images after O4 reduction show that Ni particles are anchored on the surface of praseodymium trioxide, and the precipitated Ni particles are numerous and uniform, indicating that the prepared catalyst has good uniformity. Figure 3 FT-IR further proves that for the reduced praseodymium trioxide, the Zn element is doped into the lattice of praseodymium trioxide, so the final dislocation-loaded anode catalyst, namely Ni / Pr 2-x Zn x O3(PNZx, 0≤x≤0.15).

[0099] From the data analysis in Table 1, it can be seen that the MPDs of PNZ0, PNZ0.05, PNZ0.10 and PNZ0.15 anodes are 122, 206, 314 and 130 mW / cm, respectively. 2 The output power density of the single cell with PNZ0.1 as anode is 2.6 times that of the single cell with PNZ0 as anode, indicating that Zn 2+ The above is only a preferred embodiment of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A method for preparing a staggered supported praseodymium-based anode catalyst for a direct ammonia solid oxide fuel cell, characterized in that: The chemical formula of the dislocation-supported praseodymium-based anode catalyst is Ni / Pr 2-x Zn x O3, 0<x≤0.15; The method for preparing the praseodymium-based anode catalyst for a direct ammonia solid oxide fuel cell comprises the following steps: (1) Precursor Pr2Ni 1-x Zn x Synthesis of O4 oxide According to the requirements of stoichiometry, weigh praseodymium nitrate hexahydrate and nickel salt and place them in a beaker, pour in water to dissolve, stir the solution for 50-70 minutes, and record it as solution A; according to the molar ratio of total metal ions: complexing agent in solution A is 1:1-2; according to the requirements of stoichiometric ratio, weigh zinc salt and place it in a beaker, pour in water and ammonia water to dissolve, add surfactant after the solution is completely dissolved, and record it as solution B; after the solution is prepared, adjust the speed of the magnetic stirrer to 200-700r / min, quickly pour solution A into solution B, continue stirring for 3-6 hours, stop stirring, place in a water bath, wait until the solvent evaporates completely, and the solution becomes a transparent gel, stop heating and stirring, then place the gel in an oven, set the temperature to 180-220℃, maintain for 12-24 hours, cool, grind, and calcine to obtain Pr2Ni 1-x Zn x O4 perovskite precursor; (2) Dislocation load Ni / Pr 2-x Zn x Synthesis of O3 catalyst Pr2Ni 1-x Zn x The O4 perovskite precursor was reduced in a reducing atmosphere to obtain the dislocation-loaded Ni / Pr 2-x Zn x The specific steps are as follows: prepare a viscous agent solution containing a mass fraction of 4%-10% thickener: mix the thickener and the viscous agent, heat in a water bath, keep the water bath temperature at 40-80°C, stop the water bath when the viscous agent becomes clear and transparent, cool it and put it in a refrigerator, keep the refrigerator temperature at 0-5°C; 1-x Zn x The O4 perovskite precursor and YSZ are mixed and ground for 20-60 minutes, 4-8 drops of the thickener solution are slowly added, and the grinding is continued for 20-40 minutes to obtain the pretreated anode slurry, Pr2Ni 1-x Zn x The reduction process of the O4 perovskite precursor is carried out after the battery materials are assembled, and the PNZx anode material is obtained at the SOFC device.

2. The preparation method according to claim 1, wherein: The nickel salt in step (1) is one or more of nickel chloride hexahydrate, nickel nitrate hexahydrate, nickel acetate, and nickel sulfate.

3. The preparation method according to claim 1, wherein: The zinc salt in step (1) is one or more of zinc chloride, zinc nitrate hexahydrate, and zinc acetate.

4. The preparation method according to claim 1, wherein: The complexing agent in step (1) is one or more of citric acid, oxalic acid, salicylic acid, tartaric acid, amino acid, and ethylenediaminetetraacetic acid; the surfactant in step (1) is one or more of ammonium citrate, ethylenediamine, ethylene glycol, and polyethylene glycol.

5. The preparation method according to claim 1, wherein: In step (1), the water bath temperature is maintained at 70–100°C for 4–6 hours; the calcination process in step (1) is as follows: pre-calcination at 600–800°C for 4–8 hours, with a heating rate maintained at 1–10°C / min, and then calcination at 1200°C for 2–5 hours, with a heating rate maintained at 2–5°C / min.

6. The preparation method according to claim 1, wherein: The reduction process in step (2) is as follows: introducing 10 vol%–50 vol% hydrogen / argon mixed gas into a tubular furnace and reducing at 800–1000° C. for 2–10 hours.

7. The preparation method according to claim 1, wherein: The thickener in step (3) is one of ethyl cellulose, hydroxyethyl cellulose, methyl cellulose, guar gum, hydroxypropyl methyl cellulose, and polyacrylamide; the thickener in step (3) is one of turpentine alcohol, terpineol, neroli oil, orange leaf oil, camphor oil, and lemon oil.

8. The preparation method according to claim 1, wherein: In step (3), the thickener and the viscous agent are mixed in a mass ratio of (4–10):(96–90).

9. The preparation method according to claim 1, wherein: In step (3), Pr2Ni 1-x Zn x The O4 perovskite precursor and YSZ were mixed in a mass ratio of (4–6): (6–4).

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