High-performance ammonia catalytic material and application thereof in proton conductor fuel cell

Abstract

The invention discloses a high-performance ammonia catalytic material and application of the high-performance ammonia catalytic material to a proton conductor fuel cell, and particularly relates to an anode catalytic layer based on a FeNi / BaZr0. 8Y0. 2O3-delta supported catalyst and application of the anode catalytic layer to a direct ammonia proton ceramic fuel cell (DA-PCFC). The single cell achieves a peak power density of up to 745 mWcm <-2 > under direct ammonia fuel cell operating conditions at 600 DEG C. The method avoids a traditional separated ammonia cracking device, has the advantages of high system integration level, high thermal efficiency, simple structure and the like, is simple and convenient in process and controllable in cost, has excellent large-scale preparation potential, provides a solution thought for direct ammonia fuel cells, and has important practical value and popularization prospect.

Description

Technical Field

[0001] This invention relates to the field of new energy materials and applications, specifically to an anode catalyst layer material for direct ammonia proton ceramic fuel cells, and more specifically to the use of a supported catalyst FeNi / BaZr. 0.8 Y 0.2 O 3-δ The material is applied as a catalyst layer on the anode side of a proton conductor fuel cell. Background Technology

[0002] Currently, the world is facing severe energy shortages and environmental pollution problems, making the development of green, efficient, and sustainable energy conversion and utilization technologies a research hotspot. Among numerous new energy technologies, fuel cells are considered an important direction for replacing traditional fossil fuels due to their efficient and clean energy conversion characteristics. Among these, proton ceramic fuel cells (PCFCs) have received widespread attention in recent years due to their advantages in low- and medium-temperature operation, good thermal matching, and excellent fuel adaptability. While traditional hydrogen fuels have advantages such as zero carbon emissions, their low volumetric energy density, high-pressure storage and transportation requirements, and stringent liquefaction conditions greatly limit the large-scale application of hydrogen energy technology. In contrast, ammonia (NH3), as a hydrocarbon-free hydrogen carrier, has a high volumetric energy density (12.9 MJ / L). -1 Ammonia fuel cells possess significant advantages, including easy liquefaction (requiring only 0.8 MPa at room temperature) and mature infrastructure (global annual production capacity exceeding 200 million tons), making them a promising alternative to hydrogen fuels. Ammonia can generate hydrogen through pyrolysis or catalytic decomposition, which is then used to release electricity via an electrochemical reaction, achieving a closed-loop "hydrogen storage-discharge" process. With major economies such as Japan, South Korea, and the European Union incorporating ammonia into their energy strategies, ammonia fuel cells are experiencing rapid development.

[0003] In direct ammonia PCFC (DA-PCFC) systems, the anode performs dual functions of ammonia decomposition and hydrogen oxidation. While widely used Ni-based anodes exhibit good electrocatalytic activity for hydrogen and demonstrate some ammonia decomposition capability, Ni particles are prone to coarsening, agglomeration, or nitriding under high ammonia concentrations or long-term operating conditions, leading to anode structural degradation and rapid performance decline. Therefore, improving the anti-coarsening ability and enhancing the ammonia decomposition activity of Ni-based anodes is crucial for achieving efficient and stable ammonia fuel PCFC operation.

[0004] In recent years, various noble metals (such as Pd and Rh) have been extensively studied due to their excellent ammonia cracking activity, but their high cost has limited their large-scale application. Therefore, it is necessary to develop a new technology to achieve efficient catalytic decomposition of NH3 and electrochemical oxidation of H2, in order to solve the problem of coarsening and deactivation of traditional Ni anodes and improve the power output and durability of DA-PCFC systems. Summary of the Invention

[0005] Purpose of the invention: The technical problem to be solved by the present invention is to provide a high-performance ammonia catalyst and its application in proton conductor fuel cells, which addresses the shortcomings of the prior art.

[0006] To solve the above-mentioned technical problems, the present invention discloses the following technical solution:

[0007] In a first aspect, the present invention discloses a high-performance ammonia catalytic material, namely a supported catalyst.

[0008] Among them, the supported catalyst is BaZr 0.8 Y 0.2 O 3-δ The catalyst is supported on a substrate containing Fe and Ni metals; the total loading of Fe and Ni is 2–7 wt%; the molar ratio of Fe to Ni is 1:1; and the molecular formula of the supported catalyst is 2–7 wt% FeNi / BaZr. 0.8 Y 0.2 O 3-δ In some embodiments, the total loading of the metals Fe and Ni is preferably 5 wt%, and the molecular formula of the supported catalyst is 5 wt% FeNi / BaZr. 0.8 Y 0.2 O 3-δ .

[0009] Secondly, the present invention discloses a method for preparing the supported catalyst described in the first aspect above.

[0010] The preparation method includes: (1) preparing the carrier BaZr by sol-gel method. 0.8 Y 0.2 O 3-δ (2) The supported catalyst FeNi / BaZr was prepared by impregnation method. 0.8 Y 0.2 O 3-δ .

[0011] In step (1), the preparation method of the carrier includes: dissolving Ba(NO3)2, Zr(NO3)4·5H2O and Y(NO3)3·6H2O in deionized water, heating and stirring until homogeneous to obtain a first solution; mixing ethylenediaminetetraacetic acid and citric acid monohydrate with the first solution to obtain a second solution; adjusting the pH of the second solution to 6-8, heating and stirring until the second solution becomes a viscous gel state, drying to obtain a precursor, and calcining the obtained precursor to obtain the carrier BaZr. 0.8 Y 0.2 O 3-δ (Abbreviated as carrier BZY).

[0012] The molar ratio of Ba(NO3)2, Zr(NO3)4·5H2O and Y(NO3)3·6H2O is 1:0.8:0.2; the molar ratio of the total metal ions in Ba(NO3)2, Zr(NO3)4·5H2O and Y(NO3)3·6H2O to ethylenediaminetetraacetic acid and citric acid monohydrate is 1:0.8-1.2:1.5-2.5, preferably 1:1:2.

[0013] The drying process involves drying at 150–200°C for 1–10 hours, or at 180°C for 5 hours.

[0014] The calcination is carried out at 800-1200℃ for 4-6 hours, or at 1000℃ for 5 hours.

[0015] In step (2), Fe(NO3)3·9H2O and Ni(NO3)2·6H2O are dissolved in deionized water and stirred until homogeneous to form a Fe and Ni nitrate solution; the resulting solution is then mixed with the carrier powder BaZr. 0.8 Y 0.2 O 3-δ After thorough mixing, drying, and calcination, the resulting powder is the supported catalyst FeNi / BaZr. 0.8 Y 0.2 O 3-δ .

[0016] The molar ratio of Fe(NO3)3·9H2O and Ni(NO3)2·6H2O is 1:1.

[0017] The total mass of Fe(NO3)3·9H2O and Ni(NO3)2·6H2O, and the mass of the carrier powder BaZr 0.8 Y 0.2 O 3-δ The mass ratio is 0.1 to 0.5:1; for example, 0.3:1.

[0018] The drying process involves drying at 120–180°C for 0.2–5 hours, or at 150°C for 30 minutes.

[0019] The calcination is carried out at 400-800℃ for 4-6 hours, such as at 600℃ for 5 hours.

[0020] Thirdly, the present invention discloses a supported catalyst comprising the first aspect described above or the second aspect described above. The slurry of the supported catalyst prepared by the method.

[0021] The solvent for the slurry is an alcohol-based organic solvent, preferably a mixture of isopropanol, ethylene glycol, and glycerol. More preferably, the volume ratio of isopropanol, ethylene glycol, and glycerol is 8–12:1–3:1, such as 10:2:1.

[0022] The mass-to-volume ratio of the supported catalyst to the solvent is 1g:10-16mL, such as 1g:13mL.

[0023] The slurry needs to be ultrasonicated for 20 to 40 minutes, such as 30 minutes.

[0024] Fourthly, the present invention discloses an anode for an ammonia proton conductor fuel cell.

[0025] The anode is a supported catalyst described in the first aspect or a supported catalyst prepared by the method described in the second aspect, which is loaded onto the surface of an anode material.

[0026] The anode material is NiO, and the electrolyte is BaZr. 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ A composite anode composed of soluble starch.

[0027] Among them, NiO and BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ The mass ratio of the soluble starch to the soluble starch is 5.5–7.5:2.5–4.5:1, preferably 6.5:3.5:1.

[0028] The anode material is prepared by the following method: NiO, BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ After adding soluble starch to an alcohol solvent, the mixture was ball-milled. Once the alcohol solvent evaporated, the mixture was dried to obtain Ni-BaZr. 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ Anode material (abbreviated as Ni-BZCYYb anode material).

[0029] Fifthly, the present invention discloses an ammonia proton conductor fuel cell.

[0030] The battery includes an electrolyte, and an anode and a cathode located on both sides of the electrolyte; the anode is the anode described in the fourth aspect.

[0031] Sixthly, the present invention discloses the supported catalyst described in the first aspect or the method described in the second aspect. The use of the slurry of the supported catalyst or the slurry described in the third aspect in the preparation of ammonia proton conductor fuel cells.

[0032] In a seventh aspect, the present invention discloses the ammonia proton conductor fuel cell described in the fifth and sixth aspects above. Preparation method.

[0033] The method includes the following steps:

[0034] (1) Ni-BZCYYb anode material is pressed into a mold to prepare an anode support layer and obtain a Ni-BZCYYb substrate;

[0035] (2) Spread BZCYYb evenly on the Ni-BZCYYb substrate and co-press to obtain Ni-BZCYYb|BZCYYb bilayer green sheet; calcination to obtain Ni-BZCYYb|BZCYYb half-cell bilayer sheet.

[0036] (3) The cathode paste containing BCFZY is sprayed onto the electrolyte surface of the preheated Ni-BZCYYb|BZCYYb half-cell double layer sheet to obtain Ni-BZCYYb|BZCYYb|BCFZY triple layer sheet; calcined to obtain a full cell; silver wires are connected to the cathode and anode surfaces of the obtained full cell to obtain a bare anode full cell sheet;

[0037] (4) Spraying a slurry containing the supported catalyst described in the first aspect or the supported catalyst prepared by the method described in the second aspect or the slurry described in the third aspect onto the anode surface of a preheated bare anode full cell to obtain the ammonia proton conductor fuel cell.

[0038] In step (2), the double-layer sheet is calcined at 1300-1700℃ for 2-8 hours, such as calcined at 1450℃ for 5 hours.

[0039] In step (3), the three-layer sheet is calcined at 800-1200℃ for 1-4 hours, such as 1000℃ for 2 hours.

[0040] In this invention, δ represents the oxygen vacancy content.

[0041] In this invention, the electrolyte BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ (BZCYYb) and the cathode BCFZY can be prepared according to existing technologies.

[0042] This invention provides a high-performance supported catalyst of 2-7 wt% FeNi / BaZr 0.8 Y 0.2 O 3-δThe catalyst is prepared by an impregnation-reduction method, in which Fe and Ni metal nanoparticles with synergistic catalytic capabilities are highly dispersedly loaded onto the surface of a proton conductor BZY oxide support, forming a catalyst with a metal-proton conductor heterostructure. Transition metals Fe and Ni have advantages such as low cost and complementary catalytic performance. By constructing a FeNi alloy structure, a better "nitrogen binding energy" is achieved during ammonia decomposition, improving anode catalytic efficiency. Utilizing the excellent proton conduction properties of BZY and the ammonia decomposition activity of Fe-Ni metals, the transport of hydrogen species during ammonia decomposition is effectively promoted, enhancing the hydrogen concentration at the anode and effectively improving ammonia conversion efficiency and battery output performance. Furthermore, proton conductors such as BaZr... 0.8 Y 0.2 O 3-δ (BZY) not only possesses excellent proton conductivity but also synergistically promotes hydrogen spillover at the metal / oxide interface. Therefore, a supported ammonia catalyst layer material with FeNi bimetal supported on the BZY surface was developed to construct a synergistic effect at the metal-proton conductor heterojunction interface. This solves the problems of roughening, poor structural stability, and insufficient catalytic activity of traditional Ni-based anodes under high-concentration ammonia environments, thus improving the performance and durability of fuel cells. The FeNi alloy nanoparticles in the catalyst layer of this invention effectively enhance ammonia decomposition activity, forming a rich metal-proton conductor interface with the BZY support, and interacting with the Gd support... 0.2 Ce 0.8 O 2.9-δ Compared to the (GDC) supported catalyst FN / GDC, the FN / BZY provided by this invention can effectively promote hydrogen diffusion and hydrogen species transfer, achieving the dual goals of high ammonia conversion efficiency and high power output.

[0043] The present invention provides a FeNi / BZY supported ammonia decomposition catalyst with high catalytic activity and excellent thermal stability, and its application in direct ammonia proton ceramic fuel cells, which is of great significance for promoting the application of ammonia fuel in the field of clean energy.

[0044] Beneficial effects:

[0045] The material involved in this invention is 5 wt% FeNi / BaZr 0.8 Y 0.2 O 3-δ FN / BZY was used as the anode catalytic functional layer in a direct ammonia proton ceramic fuel cell. The reduced FN / BZY anode catalytic layer exhibited excellent catalytic activity for both ammonia decomposition and hydrogen electrochemical oxidation. Testing showed that the single-cell FN / BZY|Ni-BZCYYb|BZCYYb|BCFZY achieved a maximum power density of 1032 mW / cm² in H₂ atmospheres at 600℃, 550℃, 500℃, and 450℃. -2 785mW cm -2504mW cm -2 310mW cm -2 The highest power density reached 745 mW / cm³ in an NH₃ atmosphere. -2 435mW cm -2 219mW cm -2 99mW cm -2 . Attached Figure Description

[0046] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0047] Figure 1 The X-ray diffraction (XRD) patterns of the original powders of FN / BZY and FN / GDC after reduction at 700℃ for 2 hours under H2 and treatment with ammonia at 600℃ for 100 hours (r-FN / BZY-100h NH3 and r-FN / GDC-100h NH3).

[0048] Figure 2 These are the nitrogen adsorption-desorption isotherms (BET) for FN / BZY and FN / GDC catalysts.

[0049] Figure 3 The images are field emission scanning electron microscope (FE-SEM) images of the original powders of FN / BZY and FN / GDC after reduction of the original powders of FN / BZY and FN / GDC at 700℃ for 2 hours under H2, and after treatment with ammonia at 600℃ for 100 hours (r-FN / BZY-100h NH3 and r-FN / GDC-100h NH3).

[0050] Figure 4 These are high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and energy-dispersive X-ray spectroscopy (EDX) spectra of the FN / BZY catalyst.

[0051] Figure 5 This is a transmission electron microscope (TEM) image of the FN / BZY catalyst.

[0052] Figure 6 The ammonia conversion rates of FN / BZY and FN / GDC catalysts at different temperatures are shown.

[0053] Figure 7 The stability of ammonia conversion at 600℃ is measured using FN / BZY catalyst and Ni-BZCYYb anode.

[0054] Figure 8It is the temperature-programmed desorption of ammonia (NH3-TPD) using FN / BZY and FN / GDC catalysts.

[0055] Figure 9 It is hydrogen temperature-programmed desorption (H2-TPD) of FN / BZY and FN / GDC catalysts.

[0056] Figure 10 The impedance diagrams are for symmetrical cells; a. BZCYYb-based symmetrical cell with FN / BZY catalyst layer; b. BZCYYb-based symmetrical cell with bare anode; c. Stability of symmetrical cell with FN / BZY catalyst layer and bare anode.

[0057] Figure 11 These are single-cell power density diagrams: a. Proton ceramic fuel cell with FN / BZY catalyst layer - NH3; b. Proton ceramic fuel cell with bare anode - NH3; c. Proton ceramic fuel cell with FN / BZY catalyst layer - H2; d. Proton ceramic fuel cell with bare anode - H2.

[0058] Figure 12 It is the voltage stability of the FN / BZY catalyst layer proton ceramic fuel cell.

[0059] Figure 13 These are scanning electron microscope images of a single cell after testing; a. cross-section of the cell; b. cross-section of the catalyst layer. Detailed Implementation

[0060] The present invention can be better understood from the following embodiments. However, those skilled in the art will readily understand that the descriptions in the embodiments are for illustrative purposes only and should not, and will not, limit the invention as detailed in the claims.

[0061] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; unless otherwise specified, the reagents and materials are commercially available.

[0062] The silver paste described in this invention is a paste obtained by mixing silver powder, PVB, and ethanol in a certain proportion.

[0063] This invention relates to a method for preparing a highly efficient ammonia decomposition catalyst and its application in proton ceramic fuel cells, belonging to the field of new energy materials technology. The catalyst is composed of 5 wt% FeNi alloy supported on BaZr. 0.8 Y 0.2 O 3-δ The substrate is uniformly distributed on the anode surface of a proton ceramic fuel cell via spraying. This catalyst layer exhibits superior ammonia decomposition performance at high temperatures compared to FN / GDC catalysts with different supports, achieving 100% ammonia conversion at 550℃. Figure 6 The introduction of the catalyst layer enhances the reaction interface on the hydrogen side of the anode, improving electrochemical activity. Furthermore, it effectively isolates the anode from direct contact with ammonia, suppressing nitriding reactions at high temperatures and significantly improving the stability of the fuel cell operation. At 600℃, this material imparts a peak power density of 745 mW / cm³ to the fuel cell. -2 It can operate stably for 100 hours in an ambient air temperature of 550℃. Figure 12 ).

[0064] Example 1: A method for preparing a high-performance supported catalyst FN / BZY

[0065] 1. Preparation method of carrier BZY

[0066] (1) Weigh 13.1327g of Ba(NO3)2, 17.1728g of Zr(NO3)4·5H2O and 3.8493g of Y(NO3)3·6H2O, and dissolve them in a small amount of deionized water. Weigh ethylenediaminetetraacetic acid and hydrated citric acid as complexing agents in deionized water according to a molar ratio of 1:2:1 of ethylenediaminetetraacetic acid:citric acid monohydrate:total metal ions.

[0067] (2) After adding the solution containing the complexing agent to the solution containing the metal ions, add an appropriate amount of ammonia water to make the pH of the solution reach about 7. Then, stir under magnetic stirring until the water is completely evaporated to obtain a gel-like substance.

[0068] (3) Remove the rotor from the gel, seal the mouth of the beaker with aluminum foil to prevent it from overflowing, and then put the gel-like substance into a forced-air drying oven and dry it at 180°C for 5 hours to obtain the desired foam-like precursor.

[0069] (4) Remove the beaker and let it cool. Then scrape the precursor into each crucible with a scraper. Place the precursor in a high-temperature muffle furnace and calcine at 1000℃ for 5 hours to obtain the desired carrier BZY.

[0070] 2. Preparation method of catalyst FN / BZY

[0071] (1) Weigh 0.1764g of Fe(NO3)3·9H2O and 0.1295g of Ni(NO3)2·6H2O, add a small amount of deionized water to dissolve them, and form a Fe and Ni nitrate solution.

[0072] (2) Weigh 1g of BZY powder and dissolve it in a centrifuge tube. Pour the above nitrate solution into the centrifuge tube and shake it well. Then place it on a vortex mixer and shake for 5 minutes before pouring it into a petri dish.

[0073] (3) Place it at 150℃ for constant temperature drying for 30 min, then take out the petri dish, scrape the precursor into each crucible with a scraper, and place the precursor in a tube furnace for calcination at 600℃ for 5 h to obtain the desired catalyst FN / BZY.

[0074] Comparative Example 1: Preparation of FN / GDC

[0075] 1. Preparation method of carrier GDC

[0076] (1) Weigh 34.7376g of Ce(NO3)3·6H2O and 9.0317g of Gd(NO3)3·6H2O, and dissolve them in a small amount of deionized water. Weigh ethylenediaminetetraacetic acid and hydrated citric acid as complexing agents in deionized water according to a molar ratio of 1:2:1 of ethylenediaminetetraacetic acid:citric acid monohydrate:total metal ions.

[0077] (2) After adding the solution containing the complexing agent to the solution containing the metal ions, add an appropriate amount of ammonia water to make the pH of the solution reach about 7. Then, stir under magnetic stirring until the water is completely evaporated to obtain a gel-like substance.

[0078] (3) Remove the rotor from the gel, seal the mouth of the beaker with aluminum foil to prevent it from overflowing, and then put the gel-like substance into a forced-air drying oven and dry it at 180°C for 5 hours to obtain the desired foam-like precursor.

[0079] (4) Remove the beaker and let it cool. Then scrape the precursor into each crucible with a scraper. Place the precursor in a high-temperature muffle furnace and calcine at 700°C for 5 hours to obtain the required carrier GDC.

[0080] 2. Preparation method of catalyst FN / GDC

[0081] (1) Weigh 0.1764g of Fe(NO3)3·9H2O and 0.1295g of Ni(NO3)2·6H2O, add a small amount of deionized water to dissolve them, and form a Fe and Ni nitrate solution.

[0082] (2) Weigh 1g of GDC powder and dissolve it in a centrifuge tube. Pour the above nitrate solution into the centrifuge tube and shake it well. Then place it on a vortex mixer and shake for 5 minutes before pouring it into a petri dish.

[0083] (3) Place it at 150℃ for constant temperature drying for 30 min, then take out the petri dish, scrape the precursor into each crucible with a scraper, and place the precursor in a tube furnace for calcination at 600℃ for 5 h to obtain the desired catalyst FN / GDC.

[0084] Experiment 1: Characterization and Results

[0085] 1. X-ray diffraction analysis (XRD)

[0086] Figure 1 These are the XRD patterns of FN / BZY and FN / GDC catalysts before and after the corresponding treatments. FN / BZY and FN / GDC exhibit a two-phase structure with the support phase BZY, GDC, and the active metal phase FeNi, respectively, and both are cubic crystal systems.

[0087] 2. Specific Surface Area Test (BET)

[0088] like Figure 2 As shown, the FN / BZY catalyst has a specific surface area of ​​8.2 m², as revealed by the specific surface area test. 2 g -1 The specific surface area is much larger than that of the FN / GDC catalyst, which has a surface area of ​​2.3 m². 2 g -1 The higher specific surface area indicates that the FN / BZY catalyst has better porosity, which can promote gas diffusion.

[0089] 3. Scanning electron microscope (SEM)

[0090] Figure 3 These are scanning electron microscope (SEM) images of the FN / BZY and FN / GDC catalysts. The images reveal two types of particles with different sizes. The metallic phase exhibits a nanostructure distribution on the surface of the BZY support, and the catalyst also displays a certain degree of porosity, which facilitates gas diffusion. In contrast, the FN / GDC powder shows significant particle agglomeration, and the sparse distribution of surface metallic particles may limit the exposure of effective active sites, thus negatively impacting catalytic performance.

[0091] 3. Transmission electron microscopy (TEM)

[0092] Figure 4 These are transmission electron microscopy (TEM) images of the FN / BZY catalyst. The FeNi alloy is uniformly distributed on the support surface in the form of metal clusters, without obvious agglomeration. EDX mapping results show that Ba, Zr, Y, and O are uniformly distributed, while Fe and Ni are more concentrated and exist in the form of metal clusters.

[0093] Figure 5 A high-resolution electron microscope image of the FN / BZY catalyst after hydrogen reduction at 700℃ for 2 hours. FeNi alloy is clearly observed distributed on the cubic structure of BZY after hydrogen reduction at 700℃. Furthermore, the composition of BZY and FeNi alloy can be clearly distinguished in the image, with different lattice spacings of 0.294 nm and 0.212 nm, corresponding to the (011) plane of BZY and the (111) plane of FeNi, respectively.

[0094] 4. Ammonia conversion rate test

[0095] The catalytic activity of FN / BZY and FN / GDC for NH3 conversion was tested in a quartz tube reactor within a temperature range of 400-700℃. Taking the FN / BZY sample as an example, 0.1 g of the sample and 1.4 g of quartz sand were placed in the reactor and incubated in 10 vol.% NH3-Ar at 10℃ for 1 min. -1 The heating rate was increased from room temperature to 700℃, and then the temperature was reduced to 400℃ in increments of 25℃. During this process, the gaseous components after ammonia conversion at each temperature point were analyzed using a TCD gas chromatograph and chromatographic column. Figure 6 The FN / BZY and FN / GDC catalysts were used at a space velocity of 48,000 L / kg. -1 h -1 The ammonia conversion rate under the specified conditions is shown in the figure. It is clear that the FN / BZY catalyst exhibits a high ammonia conversion rate, maintaining 99% even at 575℃, indicating its excellent ammonia catalytic ability. In contrast, the FN / GDC catalyst shows a faster activity decay rate in the ammonia decomposition reaction. Figure 7 In the catalytic stability test at 600℃, the FN / BZY catalyst maintained a near 100% ammonia conversion rate without significant degradation, demonstrating excellent catalytic stability.

[0096] 5. Ammonia temperature programmed desorption (NH3-TPD) test

[0097] The NH3-TPD of catalysts FN / BZY and FN / GDC was tested. The specific test procedure is as follows:

[0098] (1) Catalyst pretreatment: in 30 mL min -1 Under high-purity helium, the temperature is first raised to 300℃ and processed for 1 hour.

[0099] (2) NH3 adsorption: in 30 mL min -1 Under high-purity helium, after cooling to 50℃ and stabilizing the spectral baseline, switch to 30mL / min. -1 A 10% NH3-Ar mixture was ventilated for 1 hour.

[0100] (3) NH3 desorption: Switch to 30 mL min -1 High-purity helium gas was used to purge the spectrum until the baseline stabilized; then the temperature was increased from 50°C to 900°C at a rate of 5°C / min. -1 Record the spectrum.

[0101] Figure 8The NH3-TPD spectrum shows that the FN / BZY sample exhibits a low-temperature desorption peak before 200℃, attributed to weak acid sites on the surface and physically adsorbed ammonia molecules; the main peak in the 300–450℃ region corresponds to moderately strong acid sites, primarily metal ions (such as Ni). 2+ 、Fe 3+ The sample contains Lewis acidic sites formed by the presence of oxygen and metal-oxygen groups. Furthermore, the slow desorption behavior at temperatures above 450°C indicates the presence of a certain number of strongly acidic sites, possibly related to stable metal-oxygen interactions. These widely distributed acidic sites provide favorable conditions for ammonia adsorption and activation, promoting ammonia adsorption and dissociation. In contrast, the FN / GDC catalyst only shows a weak ammonia desorption peak at intermediate temperatures, indicating weaker ammonia adsorption activity. This may lead to a shorter residence time of ammonia molecules on the catalyst surface during the reaction, thus limiting the effective interaction between the active sites and ammonia.

[0102] 6. Hydrogen temperature programmed desorption (H2-TPD) test

[0103] H2-TPD tests were performed on catalysts FN / BZY and FN / GDC. The specific test procedure is as follows:

[0104] (1) Catalyst pretreatment: in 30 mL min -1 Under high-purity helium, the temperature is first raised to 300℃ and processed for 1 hour.

[0105] (2) H2 adsorption: in 30 mL min -1 Under high-purity helium, after cooling to 50℃ and stabilizing the spectral baseline, switch to 30mL / min. -1 H2-Ar, ventilate for 1 hour.

[0106] (3) H2 desorption: Switch to 30mL min -1 High-purity helium gas was used to purge the spectrum until the baseline was stable; then the temperature was increased from 50°C to 900°C at a rate of 5°C / min. -1 Record the spectrum.

[0107] Figure 9The H2-TPD spectra of the FN / BZY catalyst show a desorption peak at approximately 350 °C, corresponding to the desorption of weakly adsorbed hydrogen from the metal surface. Secondly, the small shoulder peak in the mid-temperature range of 400–500 °C may correspond to the initial overflow process at the metal-oxide interface, where activated hydrogen partially overflows from the Ni / Fe surface and migrates to the BZY surface. Furthermore, a significant hydrogen desorption peak exists in the 550–680 °C range, corresponding to the desorption behavior of strongly adsorbed hydrogen on the Ni / Fe metal surface and at its interface with BZY, indicating that the catalyst possesses excellent hydrogen activation and overflow capabilities, suppressing the "hydrogen poisoning" effect. In contrast, the FN / GDC catalyst only shows two weak desorption peaks at approximately 250 °C and 500 °C, indicating a significantly weaker adsorption and activation capacity for hydrogen. The low-temperature peak may only correspond to the physical adsorption and desorption of a small amount of hydrogen on the metal surface, while the insufficient peak intensity in the high-temperature region indicates a lack of effective hydrogen species transport at the metal-oxide interface, reducing ammonia catalytic activity.

[0108] Example 2: A method for preparing cathode powder BCFZY

[0109] (1) Weigh 13.1327g Ba(NO3)2, 5.9092g Co(NO3)2·6H2O, 8.2449g Fe(NO3)3·9H2O, 2.1466g Zr(NO3)4·5H2O, and 1.9247g Y(NO3)3·6H2O and dissolve them in a small amount of deionized water. Weigh ethylenediaminetetraacetic acid and citric acid monohydrate as complexing agents in a molar ratio of 1:2:1 to 1:2:1.

[0110] (2) After adding the solution containing the complexing agent to the solution containing the metal ions, add an appropriate amount of ammonia water to bring the pH of the solution to between 7 and 8. Then, stir under magnetic stirring until the water is completely evaporated to obtain a gel-like substance.

[0111] (3) The gel-like substance was placed in an oven and calcined at 180°C for 12 hours to obtain the desired precursor.

[0112] (4) The precursor was placed in a high-temperature muffle furnace and calcined at 1000℃ for 5 hours to obtain the required cathode powder.

[0113] Example 3: A method for preparing BZCYYb, an electrolyte material for medium- and low-temperature solid oxide fuel cells.

[0114] (1) Weigh 13.0676 g of barium nitrate, 2.1437 g of zirconium nitrate pentahydrate, 15.2026 g of cerium nitrate hexahydrate, 1.9665 g of yttrium nitrate hexahydrate, and 2.2482 g of ytterbium nitrate pentahydrate, and dissolve them in a small amount of deionized water. Weigh ethylenediaminetetraacetic acid and citric acid monohydrate as complexing agents in deionized water according to a molar ratio of 1:2:1 of ethylenediaminetetraacetic acid: citric acid hydrate: total metal ions.

[0115] (2) After adding the solution containing the complexing agent to the solution containing the metal ions, add an appropriate amount of ammonia water to bring the pH of the solution to between 7 and 8. Then, use magnetic stirring to completely evaporate the water to obtain a gel-like substance.

[0116] (3) The gel-like substance was placed in an oven and calcined at 180°C for 12 hours to obtain the desired foam-like precursor.

[0117] (4) The precursor was placed in a high-temperature muffle furnace and calcined at 1000℃ for 5 hours to obtain the desired electrolyte powder.

[0118] Example 4: Fabrication of a symmetric battery supported on an FN / BZY catalyst layer

[0119] (1) The BZCYYb electrolyte powder prepared in Example 3 and 1 wt% NiO were ball-milled with alcohol for half an hour and dried with a sodium lamp for later use. Then, 0.4 g of the ball-milled mixture of BZCYYb and NiO powder was poured into a tablet press with a diameter of 15 mm and pressed into tablets at a pressure of 1 MPa. The pressed BZCYYb and NiO mixed tablets were then calcined in a muffle furnace at 1450 °C for 5 h.

[0120] (2) Weigh 6.5g of NiO, 3.5g of BZCYYb powder prepared in Example 3, and 1g of soluble starch. Pour all of these into a ball mill jar, add an appropriate amount of ethanol, and ball mill for 30 minutes. Transfer the ball-milled anode powder solution into a mortar. Use a fan to blow air onto the mortar to accelerate the evaporation of anhydrous ethanol, while continuously stirring the solution with a pestle until the ethanol has completely evaporated. Scrape the anode powder out of the mortar with a scraper and dry it in a 65℃ constant temperature drying oven for 5 hours to finally obtain the desired Ni-BZCYYb anode powder.

[0121] (3) Weigh 1g of the powder obtained in step (2), 10ml of isopropanol, 2ml of ethylene glycol and 1ml of glycerol and pour them into a glass bottle. After sonicating in an ultrasonic machine for 30 minutes, the required anode slurry is obtained.

[0122] (4) The anode paste was uniformly sprayed onto both sides of the BZCYYb and NiO mixed sheet after calcination in step (1) using a spray gun, and then calcined at 1000℃ for 2 hours to obtain an air electrode. In order to better collect current, silver paste was uniformly brushed onto the surface of the air electrode and connected with silver wires. A symmetrical battery cell with a bare anode was successfully prepared.

[0123] (5) Weigh 1g of the FN / BZY catalyst powder prepared in Example 1, 10ml of isopropanol, 2ml of ethylene glycol and 1ml of glycerol and pour them into a glass bottle. After sonicating in an ultrasonic machine for 30 minutes, the desired catalyst coating slurry is obtained.

[0124] (5) Place the symmetrical solar cell prepared in step (3) on a heating table and preheat it at 200°C. Use a spray gun to uniformly spray the catalytic coating slurry prepared in step (4) onto the anode surface of the symmetrical solar cell under the push of inert gas. After the liquid has completely evaporated, perform the next spraying. The symmetrical solar cell with the catalytic layer is obtained after 5 sprayings.

[0125] Example 5: Fabrication of an anode-supported proton ceramic single cell loaded with an FN / BZY catalyst layer

[0126] (1) Weigh 6.5g of NiO, 3.5g of BZCYYb powder prepared in Example 3, and 1g of soluble starch. Pour all of them into a ball mill jar, add an appropriate amount of ethanol, and ball mill for 30 minutes. Transfer the ball-milled anode powder solution into a mortar, use a fan to blow on the mortar to accelerate the evaporation of anhydrous ethanol, and stir the solution continuously with a pestle until the ethanol is completely evaporated. Scrape the anode powder out of the mortar with a scraper, place it in a 65℃ constant temperature drying oven and dry for 5 hours to finally obtain the required Ni-BZCYYb anode powder.

[0127] (2) 0.25g of Ni-BZCYYb powder was weighed and pre-pressed in a 15mm diameter mold at a pressure of 200MPa. Then, 0.015g of BZCYYb powder was weighed and evenly spread on the Ni-BZCYYb substrate. The substrate was co-pressed at a pressure of about 300MPa to obtain a Ni-BZCYYb|BZCYYb bilayer green sheet. The green sheet was then calcined at 1450℃ for 5h to densify the BZCYYb, thus obtaining a Ni-BZCYYb|BZCYYb half-cell bilayer sheet.

[0128] (3) Weigh 1g of the BCFZY cathode powder prepared in Example 2, 10ml of isopropanol, 2ml of ethylene glycol and 1ml of glycerol and pour them into a glass bottle. After sonicating in an ultrasonic machine for 30 minutes, the desired cathode slurry is obtained.

[0129] (4) The prepared half-cell bilayer sheet was placed on a heating table and preheated at 200°C. Using a spray gun and propelled by inert gas, the prepared cathode slurry was uniformly sprayed onto the electrolyte surface of the dry-pressed sheet. After the liquid had completely evaporated, the next spraying was performed. The half-cell with seven sprayings was placed in a high-temperature muffle furnace and calcined at 1000°C for 2 hours to obtain a full cell. To improve current collection, silver wires were connected to the cathode and anode surfaces. A full cell with a bare anode was successfully prepared.

[0130] (5) Weigh 1g of the FN / BZY catalyst powder prepared in Example 1, 10ml of isopropanol, 2ml of ethylene glycol and 1ml of glycerol and pour them into a glass bottle. After sonicating in an ultrasonic machine for 30 minutes, the desired catalyst coating slurry is obtained.

[0131] (6) Place the full cell prepared in step (4) on a heating table and preheat it at 200°C. Use a spray gun to uniformly spray the catalytic coating slurry prepared in step (5) onto the anode surface of the full cell under the push of inert gas. After the liquid has completely evaporated, perform the next spraying. The full cell with the catalytic layer is obtained after 5 sprayings.

[0132] Experiment 2: Battery test output power and results

[0133] The symmetrical cell prepared in Example 4 and the full cell prepared in Example 5 were reduced in a hydrogen atmosphere at 650°C for 1 hour, and then electrochemical tests were performed in the temperature ranges of 500–700°C and 450–600°C, respectively.

[0134] 1. Symmetrical cell test

[0135] Symmetric cells of BZCYYb with an FN / BZY catalyst layer and a bare anode were tested. The symmetric cells were incubated at 60 mL / min. -1 Under a hydrogen atmosphere, the temperature was raised from room temperature to 700°C, and after reduction for 30 min, 20 mL of [unspecified solution] was added. -1 Ammonia gas was used to measure the areal impedance (ASR) of the BZCYYb-supported symmetric cell by electrochemical impedance spectroscopy (EIS) to further evaluate the difference in catalytic activity between the FN / BZY-supported catalyst layer and the bare anode. Figure 10 As can be seen, the introduction of the catalyst layer increases the ammonia decomposition rate and accelerates gas diffusion and surface reaction processes. The battery loaded with the FN / BZY catalyst layer exhibits relatively low polarization resistance. Furthermore, considering the stability of symmetrical cells, the symmetrical cell loaded with the catalyst layer shows a slower increase in polarization resistance compared to the bare anode, indicating that the catalyst layer plays a positive role in mitigating anodic polarization and enhancing interfacial reaction activity.

[0136] 2. Full-cell electrochemical performance testing

[0137] Electrochemical performance tests were performed on a full cell with an FN / BZY catalyst layer and a bare anode. The cathode of the full cell was set to 100 mL / min. -1 Under air atmosphere, the anode is at 80 mL min -1 In a hydrogen atmosphere, the temperature was raised from room temperature to 600°C, and after reduction for 30 min, 40 mL of hydrogen was cut into the anode. -1 For ammonia gas, we tested the current-voltage (IV) and current-power (IP) curves of the full cell using a Keithley 2420. To enhance the catalytic decomposition of ammonia fuel by the anode, an FN / BZY catalyst was loaded onto the anode surface of a Ni-BZCYYb|BZCYYb|BCFZY single cell using a spray coating process. The catalyst layer thickness was approximately 7 μm. Figure 13 As shown. Figure 11 As shown, the test results using ammonia as fuel at 600℃ demonstrate that the battery loaded with the FN / BZY catalyst layer achieved 745 mW / cm². -2 The peak power density is significantly better than that of the bare anode without a catalyst layer (594 mW / cm²). -2 Specifically, under an ammonia atmosphere at 600℃, 550℃, 500℃, and 450℃, the full-cell power densities of the bare anode were 594, 348, 171, and 58 mW cm⁻¹, respectively. -1 The power densities of the full cells containing the FN / BZY catalyst layer were 745, 435, 219, and 99 mW / cm², respectively. -1 It is far superior to batteries without a catalytic coating.

[0138] This performance improvement is primarily attributed to the excellent ammonia decomposition activity and favorable interfacial synergistic effect of the FN / BZY composite catalyst. Specifically, the FeNi alloy component provides abundant active sites during ammonia dissociation, accelerating the conversion of ammonia to hydrogen. More importantly, the proton conductor support BZY plays a "hydrogen spillover" role in this process: after hydrogen dissociates into active hydrogen atoms on the metal surface, it can migrate to the BZY surface through the metal-support interface, facilitating hydrogen atom diffusion and significantly promoting hydrogen reaction kinetics. Furthermore, the FN / BZY catalyst layer helps form a stable catalytic interface, blocking direct contact between ammonia and the anode metal, reducing the risk of metal agglomeration caused by the nitriding reaction, and thus delaying electrode degradation. (The last sentence appears to be incomplete and possibly refers to a specific performance parameter.) -2 Under these conditions, a single cell with a supported catalyst layer can achieve stable operation for up to 100 hours. Figure 12 It exhibits excellent thermal stability and resistance to ammonia corrosion.

[0139] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A supported catalyst, characterized in that, The supported catalyst is BaZr 0.8 Y 0.2 O 3-δ The substrate is used as a carrier to load metals Fe and Ni; the total loading of Fe and Ni is 2-7 wt%; preferably, the molar ratio of Fe to Ni is 1:1; δ is the oxygen vacancy content.

2. The method for preparing the supported catalyst according to claim 1, characterized in that, BaZr carrier prepared by sol-gel method 0.8 Y 0.2 O 3-δ The supported catalyst FeNi / BaZr was prepared by impregnation method. 0.8 Y 0.2 O 3-δ .

3. The preparation method according to claim 2, characterized in that, The preparation method of the carrier includes: dissolving Ba(NO3)2, Zr(NO3)4·5H2O and Y(NO3)3·6H2O in deionized water to obtain a first solution; mixing ethylenediaminetetraacetic acid and citric acid monohydrate with the first solution to obtain a second solution; adjusting the pH of the second solution to 6-8, heating and stirring until the second solution becomes a viscous gel state, drying to obtain a precursor, and calcining the obtained precursor to obtain the carrier BaZr. 0.8 Y 0.2 O 3-δ ; Preferably, the molar ratio of Ba(NO3)2, Zr(NO3)4·5H2O and Y(NO3)3·6H2O is 1:0.8.0:0.2; the molar ratio of the total metal ions in Ba(NO3)2, Zr(NO3)4·5H2O and Y(NO3)3·6H2O to ethylenediaminetetraacetic acid and citric acid monohydrate is 1:0.8-1.2:1.5-2.

5. Preferably, the drying is performed at 150–200°C for 1–10 hours; and / or the calcination is performed at 800–1200°C for 4–6 hours.

4. The preparation method according to claim 2, characterized in that, Fe(NO3)3·9H2O and Ni(NO3)2·6H2O were dissolved in deionized water, and the resulting solution was mixed with the carrier powder BaZr. 0.8 Y 0.2 O 3-δ After stirring evenly and drying, the supported catalyst FeNi / BaZr was obtained by calcination. 0.8 Y 0.2 O 3-δ ; Preferably, the molar ratio of Fe(NO3)3·9H2O to Ni(NO3)2·6H2O is 1:1; the total mass of Fe(NO3)3·9H2O and Ni(NO3)2·6H2O, and the molar ratio of the carrier powder BaZr, are... 0.8 Y 0.2 O 3-δ The mass ratio is 0.1–0.5:1; Preferably, the drying is performed at 120–180°C for 0.2–5 hours; and / or the calcination is performed at 400–800°C for 4–6 hours.

5. A slurry containing the supported catalyst according to claim 1 or the supported catalyst prepared by any one of claims 2 to 4, characterized in that, The solvent for the slurry is an alcohol-based organic solvent, preferably a mixture of isopropanol, ethylene glycol, and glycerol. More preferably, the volume ratio of isopropanol, ethylene glycol, and glycerol is 8–12:1–3:

1. The mass-volume ratio of the supported catalyst to the solvent is 1 g:10–16 mL.

6. An anode for an ammonia proton conductor fuel cell, characterized in that, The supported catalyst of claim 1 or the supported catalyst prepared by any one of claims 2 to 4 is loaded onto the surface of the anode material.

7. The anode according to claim 6, characterized in that, The anode material is NiO or BaZr. 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ A composite anode composed of soluble starch.

8. The anode according to claim 7, characterized in that, The NiO and BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ The mass ratio of NiO to soluble starch is 5.5–7.5:2.5–4.5:1; preferably, the anode material is prepared by the following method: NiO, BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ After adding soluble starch to an alcohol solvent, the mixture was ball-milled. Once the alcohol solvent evaporated, the mixture was dried to obtain Ni-BaZr. 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ Anode material.

9. An ammonia proton conductor fuel cell, characterized in that, It includes an electrolyte, and an anode and a cathode located on either side of the electrolyte; the anode is the anode described in any one of claims 6 to 8.

10. The method for preparing the ammonia proton conductor fuel cell according to claim 9, characterized in that, Includes the following steps: (1) Ni-BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ The anode material is press-formed in a mold to obtain Ni-BaZr. 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ Base; (2) BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ Evenly spread on Ni-BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ Ni-BaZr was obtained by co-pressing on the substrate. 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ |BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ Double-layer green sheet; calcination to obtain Ni-BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ |BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ Half-cell double-layer film; (3) The cathode paste containing BCFZY was sprayed onto the preheated Ni-BaZr. 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ |BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ The electrolyte surface in the half-cell bilayer sheet is calcined to obtain a full cell; silver wires are connected to the cathode and anode surfaces of the obtained full cell to obtain a full cell sheet with a bare anode; (4) Spray the slurry containing the supported catalyst of claim 1 or the supported catalyst prepared by any one of claims 2 to 4 or the slurry of claim 5 onto the anode surface of a preheated bare anode full cell to obtain the ammonia proton conductor fuel cell.

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