Hydrogen electrode material and preparation method and application thereof
Hydrogen electrode materials on porous YSZ substrates were prepared by hydrothermal reaction and precipitation deposition techniques, which solved the problems of poor activity and stability of existing SOEC hydrogen electrode materials, and achieved more efficient water vapor dissociation and hydrogen ion transport, thereby improving battery performance and lifespan.
Patent Information
- Application Number
- CN202511188057.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-25
- Publication Date
- 2025-11-21
AI Technical Summary
Existing SOEC hydrogen electrode materials have poor activity and stability. Traditional preparation methods result in a small effective three-phase interface and poor performance under high temperature and high humidity conditions.
A porous YSZ substrate with a MOF-like structure was prepared by hydrothermal reaction. Nanoscale nickel hydroxide was deposited by precipitation and then calcined to form a Ni+YSZ mixture, which increased the contact interface between the two phases and improved the dispersibility and chemical interaction of the material.
It significantly improves the stability and oxidation resistance of hydrogen electrode materials, enhances water vapor dissociation and hydrogen ion transport capabilities, and extends the lifespan of SOEC batteries.
Smart Images
Figure CN120989648A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of solid oxide electrolysis cell technology, specifically relating to a hydrogen electrode material, its preparation method, and its application. Background Technology
[0002] SOEC, or Solid Oxide Electrolyte, is a device that decomposes water to produce hydrogen under high-temperature conditions. Due to its high operating temperature (500–1000℃), SOEC can achieve an electrolysis efficiency of up to 90%, while alkaline and PEM electrolyzers, operating at temperatures typically between 70–90℃, have efficiencies of only 42–78% and 48–65%, respectively, significantly lower than SOEC. In terms of raw material adaptability, SOEC can use carbon dioxide as a feedstock in addition to water to produce hydrogen or a mixture of hydrogen and carbon monoxide as syngas. Furthermore, SOEC utilizes waste heat, resulting in higher energy efficiency and lower operating costs compared to other low-temperature electrolysis systems.
[0003] Although SOEC has significant advantages in hydrogen production, it also faces many development challenges, such as: ① high cost of electrode materials; ② high manufacturing cost of SOEC system components; ③ high system operation and maintenance cost; ④ poor high-temperature stability of electrode materials; ⑤ system integration and matching; and ⑥ complex system standardization. Currently, the commonly used hydrogen electrode material for SOEC is Ni-YSZ (yttrium-stabilized zirconium oxide). The traditional preparation method for YSZ is a conventional solid-state method, which involves simple physical mixing and grinding of conventional micron-sized, irregular nickel oxide to control a specific particle size range for use as a hydrogen electrode material. Although the preparation process is simple, the effective three-phase interface between the two phases is much smaller than expected, resulting in poor activity and stability of the hydrogen electrode.
[0004] Therefore, developing a SOEC hydrogen electrode material with high activity and good stability is of great significance. Summary of the Invention
[0005] The purpose of this invention is to overcome the problems existing in the prior art and to provide a hydrogen electrode material, its preparation method, and its application.
[0006] This invention is achieved through the following technical solution:
[0007] In a first aspect, the present invention provides a method for preparing a hydrogen electrode material, comprising the following steps:
[0008] S1. Prepare a mixed solution A containing zirconium salt and yttrium salt, prepare a mixed solution B containing ligand, mix mixed solution A and mixed solution B, adjust the pH of the solution to acidic, carry out a hydrothermal reaction, wash, and dry to obtain a precursor; the ligand includes at least one of terephthalic acid, trimesic acid, and bipyridine;
[0009] S2. Add alkali to the nickel salt solution to adjust the pH of the solution to be greater than 10, separate and wash the solid to obtain nickel salt precipitate;
[0010] S3. Mix the nickel salt precipitate obtained in step S2 with the precursor obtained in step S1, add hydration slurry to obtain mixture C, and then separate the solid and liquid components of the mixture C to obtain the product precipitate.
[0011] S4. Calcine the precipitate obtained in step S3 to obtain the hydrogen electrode material.
[0012] This invention provides a method for preparing a porous YSZ substrate with a MOF-like structure via a hydrothermal reaction. Nanoscale nickel hydroxide is then deposited onto the porous YSZ using a precipitation deposition method. After calcination, a Ni+YSZ mixture phase hydrogen electrode material is obtained. This process significantly enhances the contact interface between YSZ and Ni, indirectly increasing the three-phase interface of the active electrode layer. The porous YSZ not only effectively disperses Ni particles and inhibits their migration and aggregation under high temperature and humidity conditions, but also, due to the increased contact area, improves the chemical interaction between YSZ and Ni, promoting water vapor dissociation and reducing the corrosion and oxidation of nickel by water vapor. Therefore, it significantly improves the stability of the hydrogen electrode material.
[0013] The porous YSZ precursor with a MOF-like structure obtained in step S1 of this invention is affected by the type of ligand, which affects the growth process of the grains and ultimately the morphology and pore size of the formed porous structure. This invention uses at least one of terephthalic acid, trimesic acid, and bipyridine as ligands, which can effectively control the morphology and pore size of the final mesopores. If other ligands are used, only micropores may be obtained, or the structure may be mainly plate-like and unable to form a porous structure.
[0014] Preferably, in step S1, the molar ratio of the zirconium salt to the ligand is 1:(1-4).
[0015] Furthermore, this invention optimizes the molar ratio of zirconium salt to ligand. A molar ratio of zirconium salt to ligand greater than 1:4 will affect grain growth, the morphology and crystallinity of the material, and excessive use will also lead to waste. A molar ratio less than 1:1 will not allow for morphology control, and may result in some parts having MOF-like structures and others being solid or having other morphologies.
[0016] Preferably, in step S1, the temperature of the hydrothermal reaction is 100℃-150℃, and the time is 20h-30h.
[0017] The temperature and time of the hydrothermal reaction also affect the formation of porous structures. In this invention, the hydrothermal reaction time is controlled at 20-30 hours. If the reaction time is too short, a sheet-like structure is generated, and a three-dimensional porous structure cannot be formed. If the reaction time is too long, the particle size distribution is too wide, and a microporous structure is formed, which is close to the standard MOF structure. It is impossible to obtain the structure in which the mesopore ratio is greater than the micropore ratio. The reaction temperature is controlled at 100-150℃. If the temperature is too low, the reaction cannot occur to obtain the YSZ precursor. If the temperature is too high, a porous structure cannot be formed, and solid particles are formed in the end.
[0018] This invention attaches nickel to the pore surface of a porous structure. MOF structures typically have pore sizes below a few nanometers, which is too small. Therefore, this invention controls the formation of a MOF-like porous structure by selecting the ligand type, adjusting the ligand dosage, and controlling the time and temperature of the thermal reaction. This structure contains micropores smaller than 2 nm and mesopores of 2-50 nm, with mesopores accounting for more than 50%. This achieves better penetration and loading of larger nickel salt precipitates, making it easier to improve the structural stability, reproducibility, and batch consistency of the composite material.
[0019] Preferably, in step S1, the zirconium salt includes at least one of zirconium chloride, zirconium nitrate, and zirconium sulfate.
[0020] Preferably, in step S1, the yttrium salt includes at least one of yttrium chloride, yttrium nitrate, and yttrium sulfate.
[0021] Preferably, in step S1, the solvents in mixture A and mixture B are independent and include at least one of N,N-dimethylformamide (DMF), N,N-diethylformamide (DEF), and dimethyl sulfoxide (DMSO).
[0022] Preferably, in step S1, the molar ratio of zirconium in the zirconium salt to yttrium in the yttrium salt is 23:4.
[0023] When the ratio of zirconium to yttrium is 23:4, 8YSZ can be obtained, thus producing a hydrogen electrode material with good conductivity and stable structure.
[0024] Preferably, in step S1, the pH of the solution is adjusted using an acid solution, and the pH of the solution is 4-6.
[0025] Optionally, the acid solution includes at least one of acetic acid, formic acid, and phosphoric acid; the amount of acid solution used is 5 mL to 10 mL.
[0026] Preferably, in step S1, the washing is performed no less than 3 times; the washing process first uses DMF and then methanol.
[0027] During washing, DMF is used to remove unreacted products and some byproducts. The purpose of washing with methanol is to replace the DMF in the channels and further remove byproducts. Methanol is also easier to dry, thereby improving the consistency of the material.
[0028] Preferably, in step S1, the drying is performed using vacuum drying, and the drying temperature is 130℃-150℃ for 5h-8h.
[0029] Drying under vacuum conditions creates negative pressure, allowing for more thorough solvent removal. If the drying temperature is too low, the drying will be incomplete and take too long; if the drying temperature is too high, it is equivalent to calcining the precursor, which will not maintain the precursor's state and will affect the batch consistency of subsequent materials. If the drying time is too short, the drying will be incomplete; if the drying time is too long, the energy consumption will be too high and the cost will be too high.
[0030] Preferably, in step S2, the nickel salt includes at least one of nickel nitrate, nickel chloride, and nickel sulfate.
[0031] Preferably, the molar ratio of nickel in the nickel salt in step S2 to zirconium in the zirconium salt in step S1 is 1.7:1-7:1.
[0032] The present invention preferably uses a nickel to zirconium molar ratio of ≥1.7:1 (calculated with a nickel oxide: YSZ mass ratio of ≥1:1). If the nickel to zirconium molar ratio is lower than 1.7:1, the nickel content in the final product will be too low, which will affect the conductivity and make it unusable as an electrode.
[0033] Preferably, in step S2, the alkaline solution is a strong alkaline solution; optionally, the alkaline solution includes at least one of sodium hydroxide solution and potassium hydroxide solution; the concentration of the alkaline solution is 0.5 mol / L-3 mol / L.
[0034] Preferably, in step S2, the separation is performed by vacuum filtration, and the washing is performed by water centrifugation until the conductivity is less than 20 μS / cm.
[0035] Simply adjust the pH value to be greater than 10 using an alkaline solution; the amount used does not need to be specially controlled. Centrifugation and washing until the conductivity is less than 20 μS / cm is to remove impurity metal ions introduced by the alkaline solution from the precipitate.
[0036] Preferably, in step S2, the D50 particle size of the nickel salt precipitate is 0.01 μm-0.06 μm; more preferably, the D50 particle size of the nickel salt precipitate is 0.02 μm-0.05 μm.
[0037] Since the nickel salt precipitate is used for interpenetration with the YSZ precursor, its particle size distribution and morphology are crucial to the two-phase infiltration. Therefore, the preferred D50 particle size of the nickel salt precipitate is 0.01 μm-0.06 μm, and more preferably, a near-spherical morphology with a D50 of 0.02-0.05 μm, which is more conducive to diffusion and dispersion within the pores of the YSZ precursor. After high-temperature calcination, it has a stronger anchoring effect on the surface of the YSZ precursor, indirectly enhancing the chemical interaction between the two. When used as a SOEC hydrogen electrode, it can improve water dissociation and hydrogen ion transport, reduce the half-reaction barrier, and increase the reaction rate.
[0038] Preferably, in step S3, the solid content of the mixture C is ≤20wt%.
[0039] Preferably, in step S3, the temperature during pulping is 50℃-120℃; more preferably, in step S3, the temperature during pulping is 60℃-100℃.
[0040] In step S3, the solid content of the mixture C is ≤20wt%. If the solid content is too high and the mixture is too viscous, it will affect the mixing effect. During the process of fully mixing the raw material powder with the solvent through ball milling and other processes to form a uniform slurry, the temperature is controlled at 50℃-120℃, more preferably 60℃-100℃. If the temperature is too low, the nickel salt precipitate may not be well dispersed in the channels of YSZ. If the temperature is too high, it may cause YSZ to agglomerate, affecting the particle size distribution after subsequent calcination, thereby affecting the performance of the material.
[0041] Optionally, the pulping time can be greater than 3 hours, specifically 3-10 hours.
[0042] Preferably, in step S4, the calcination temperature is 240℃-400℃ and the calcination time is 2h-4h.
[0043] In the calcination process of step S4 of this invention, the temperature is controlled at 240-400℃. If the temperature is too low, the precursor will not decompose completely, the product will be impure and the crystallinity of the product will decrease. If the temperature is too high, the material structure will collapse.
[0044] Secondly, the present invention provides a hydrogen electrode material prepared by the method for preparing the hydrogen electrode material.
[0045] Thirdly, the present invention provides the application of the hydrogen electrode material in a solid oxide electrolyzer.
[0046] Compared with the prior art, the present invention has the following beneficial effects:
[0047] This invention employs a high-pressure hydrothermal reaction to synthesize MOF-like YSZ powder. Nickel species are then deposited onto the porous inner wall of the YSZ powder to improve its dispersibility. After calcination, the contact surface between the two phases and the anti-agglomeration and anti-oxidation properties of the nickel electrode are significantly enhanced, ultimately improving the temperature and moisture corrosion resistance of the hydrogen electrode material. The MOF-like porous YSZ powder not only has a larger specific surface area for better dispersibility of nickel salt precipitates, but also, after calcination, the stronger chemical interaction between the better dispersed nickel salt precipitates and YSZ further facilitates water dissociation, hydrogen ion transport, and water vapor diffusion, resulting in a significant improvement in the overall SOEC battery performance. The preparation of spherical nickel salt precipitates and the control of specific particle size distribution further improve the stability of the entire process and the reproducibility of the composite material. This invention effectively regulates the hydrogen electrode material from the aspects of preparation process, material selection, and process scale-up, achieving breakthroughs in SOEC battery performance and significantly extending its service life. Attached Figure Description
[0048] Figure 1 Electron micrograph of the precursor prepared in Comparative Example 1;
[0049] Figure 2 Electron micrograph of the precursor prepared in Comparative Example 2;
[0050] Figure 3 Electron micrograph of the precursor prepared in Example 1. Detailed Implementation
[0051] To better illustrate the objectives, technical solutions, and advantages of this invention, the invention will be further described below with reference to specific embodiments. Those skilled in the art should understand that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
[0052] Unless otherwise specified, the experimental methods used in the examples are conventional methods; the materials and reagents used are commercially available unless otherwise specified.
[0053] Example 1
[0054] A method for preparing a hydrogen electrode material includes the following steps:
[0055] S1. Dissolve 0.1g of ZrCl4 solid and 0.0146g of YCl3 solid in 10mL of DMF. Stir magnetically at 60℃ until completely dissolved to obtain solution A. Weigh 0.1g of terephthalic acid and dissolve it in 5mL of DMF. Stir continuously until transparent to obtain solution B. Mix solution A and solution B, add 5mL of glacial acetic acid, and stir for 30 minutes to obtain a mixed solution. Transfer the mixed solution to a reaction vessel, place the reaction vessel in an oven, and carry out a hydrothermal reaction at 120℃ for 24 hours. After the reaction is completed, allow it to cool naturally to room temperature to obtain the precursor solution.
[0056] The precursor solution was transferred to a centrifuge tube and centrifuged at 8000 rpm for 10 minutes. The supernatant was discarded to obtain the precipitate. The precipitate was washed three times with 20 mL of DMF each time, and then washed three times with methanol to replace the DMF in the channels. The washed precipitate was placed in a vacuum oven and dried at 60 °C for 12 hours. The temperature was then increased to 150 °C and kept under vacuum for 6 hours to completely remove the residual solvent in the channels and obtain the precursor.
[0057] S2. Dissolve 0.5g of Ni(NO3)2·6H2O solid in 50mL of water and stir for 20 minutes until completely dissolved to obtain a transparent nickel salt solution. Slowly add 0.5mol / L sodium hydroxide solution to the above nickel nitrate solution, controlling the pH to be greater than 10. Filter and wash with water by centrifugation until the conductivity is less than 20μS / cm to obtain a nickel salt precipitate; the D50 particle size of the nickel salt precipitate is 0.03μm.
[0058] S3. Mix the nickel salt precipitate obtained in step S2 with the precursor obtained in step S1, add deionized water and stir at 80°C for 10 hours to form a slurry, control the solid content to 12wt%, filter and obtain the product precipitate.
[0059] S4. The product precipitate obtained in step S3 is calcined in air at 350°C for 3 hours. The cooled reaction product is discharged, ground to the target particle size, sieved through a screen and packaged to obtain the hydrogen electrode material.
[0060] Example 2
[0061] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in Example 1 is that the molar ratio of zirconium salt ZrCl4 to ligand terephthalic acid is different in step S1, while the rest is the same as in Example 1. The molar ratio of zirconium salt to ligand in this embodiment is shown in Table 1 below.
[0062] Example 3
[0063] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in Example 1 is that the molar ratio of zirconium salt ZrCl4 to ligand terephthalic acid is different in step S1, while the rest is the same as in Example 1. The molar ratio of zirconium salt to ligand in this embodiment is shown in Table 1 below.
[0064] Example 4
[0065] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the temperature of the hydrothermal reaction in step S1 is different, while the rest is the same as in embodiment 1. The temperature of the hydrothermal reaction in this embodiment is shown in Table 1 below.
[0066] Example 5
[0067] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the temperature of the hydrothermal reaction in step S1 is different, while the rest is the same as in embodiment 1. The temperature of the hydrothermal reaction in this embodiment is shown in Table 1 below.
[0068] Example 6
[0069] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the hydrothermal reaction time is different in step S1, while the rest is the same as in embodiment 1. The hydrothermal reaction time in this embodiment is shown in Table 1 below.
[0070] Example 7
[0071] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the hydrothermal reaction time is different in step S1, while the rest is the same as in embodiment 1. The hydrothermal reaction time in this embodiment is shown in Table 1 below.
[0072] Example 8
[0073] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in Example 1 is that the ligand in step S1 is not terephthalic acid, but all other aspects are the same as in Example 1. The ligands in this embodiment are shown in Table 1 below.
[0074] Example 9
[0075] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in Example 1 is that the ligand in step S1 is not terephthalic acid, but all other aspects are the same as in Example 1. The ligands in this embodiment are shown in Table 1 below.
[0076] Example 10
[0077] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in Example 1 is that the particle size of the nickel salt precipitate in step S2 is different, while the rest is the same as in Example 1. The particle size of the nickel salt precipitate in this embodiment is shown in Table 2 below.
[0078] Example 11
[0079] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in Example 1 is that the particle size of the nickel salt precipitate in step S2 is different, while the rest is the same as in Example 1. The particle size of the nickel salt precipitate in this embodiment is shown in Table 2 below.
[0080] Example 12
[0081] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the stirring and slurry-forming temperature in step S3 is different, while the rest is the same as in embodiment 1. The stirring temperature in step S3 of this embodiment is shown in Table 2 below.
[0082] Example 13
[0083] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the stirring and slurry-forming temperature in step S3 is different, while the rest is the same as in embodiment 1. The stirring temperature in step S3 of this embodiment is shown in Table 2 below.
[0084] Example 14
[0085] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the calcination temperature in step S4 is different, while the rest is the same as in embodiment 1. The calcination temperature in step S4 of this embodiment is shown in Table 2 below.
[0086] Example 15
[0087] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the calcination temperature in step S4 is different, while the rest is the same as in embodiment 1. The calcination temperature in step S4 of this embodiment is shown in Table 2 below.
[0088] Example 16
[0089] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is the calcination time in step S4. All other steps are the same as in embodiment 1. The calcination time in step S4 of this embodiment is shown in Table 2 below.
[0090] Example 17
[0091] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is the calcination time in step S4. All other steps are the same as in embodiment 1. The calcination time in step S4 of this embodiment is shown in Table 2 below.
[0092] Example 18
[0093] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in Example 1 is that the particle size of the nickel salt precipitate in step S2 is different, while the rest is the same as in Example 1. The particle size of the nickel salt precipitate in this embodiment is shown in Table 2 below.
[0094] Example 19
[0095] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in Example 1 is that the particle size of the nickel salt precipitate in step S2 is different, while the rest is the same as in Example 1. The particle size of the nickel salt precipitate in this embodiment is shown in Table 2 below.
[0096] Example 20
[0097] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the stirring and slurry-forming temperature in step S3 is different, while the rest is the same as in embodiment 1. The stirring temperature in step S3 of this embodiment is shown in Table 2 below.
[0098] Example 21
[0099] The difference between the preparation method of the hydrogen electrode material in this embodiment and that in embodiment 1 is that the stirring and slurry-forming temperature in step S3 is different, while the rest is the same as in embodiment 1. The stirring temperature in step S3 of this embodiment is shown in Table 2 below.
[0100] Comparative Example 1
[0101] The preparation method of the hydrogen electrode material in this comparative example differs from that in Example 1 in that the ligand in step S1 is not terephthalic acid, while all other aspects are the same as in Example 1. The ligands in this comparative example are shown in Table 1 below.
[0102] Comparative Example 2
[0103] The preparation method of this comparative hydrogen electrode material differs from that of Example 1 in that the molar ratio of zirconium salt ZrCl4 to ligand terephthalic acid is different in step S1, and the particle size of the nickel salt precipitate is different in step S2. All other aspects are the same as in Example 1. The molar ratio of zirconium salt to ligand in this comparative example is shown in Table 1 below, and the particle size of the nickel salt precipitate is shown in Table 2 below.
[0104] Comparative Example 3
[0105] The preparation method of this comparative hydrogen electrode material differs from that of Example 1 in that the molar ratio of zirconium salt ZrCl4 to ligand terephthalic acid is different in step S1, and the particle size of the nickel salt precipitate is different in step S2. All other aspects are the same as in Example 1. The molar ratio of zirconium salt to ligand in this comparative example is shown in Table 1 below, and the particle size of the nickel salt precipitate is shown in Table 2 below.
[0106] Comparative Example 4
[0107] The preparation method of the hydrogen electrode material in this comparative example differs from that in Example 1 in that the temperature of the hydrothermal reaction in step S1 is different, while the rest is the same as in Example 1. The temperature of the hydrothermal reaction in this comparative example is shown in Table 1 below.
[0108] Comparative Example 5
[0109] The preparation method of the hydrogen electrode material in this comparative example differs from that in Example 1 in that the temperature of the hydrothermal reaction in step S1 is different, while the rest is the same as in Example 1. The temperature of the hydrothermal reaction in this comparative example is shown in Table 1 below.
[0110] Comparative Example 6
[0111] The preparation method of the hydrogen electrode material in this comparative example differs from that in Example 1 in that the hydrothermal reaction time is different in step S1, while all other steps are the same as in Example 1. The hydrothermal reaction time of this comparative example is shown in Table 1 below.
[0112] Comparative Example 7
[0113] The preparation method of the hydrogen electrode material in this comparative example differs from that in Example 1 in that the hydrothermal reaction time is different in step S1, while all other steps are the same as in Example 1. The hydrothermal reaction time of this comparative example is shown in Table 1 below.
[0114] Comparative Example 8
[0115] The preparation method of the hydrogen electrode material in this comparative example differs from that in Example 1 in that the calcination temperature in step S4 is different, while all other steps are the same as in Example 1. The calcination temperature in step S4 of this comparative example is shown in Table 2 below.
[0116] Comparative Example 9
[0117] The preparation method of the hydrogen electrode material in this comparative example differs from that in Example 1 in that the calcination temperature in step S4 is different, while all other steps are the same as in Example 1. The calcination temperature in step S4 of this comparative example is shown in Table 2 below.
[0118] Comparative Example 10
[0119] The preparation method of the hydrogen electrode material in this comparative example differs from that in Example 1 in that the calcination time in step S4 is different, while all other steps are the same as in Example 1. The calcination time in step S4 of this comparative example is shown in Table 2 below.
[0120] Comparative Example 11
[0121] The preparation method of the hydrogen electrode material in this comparative example differs from that in Example 1 in that the calcination time in step S4 is different, while all other steps are the same as in Example 1. The calcination time in step S4 of this comparative example is shown in Table 2 below.
[0122] The pore size of the precursors prepared in step S1 of Examples 1-9 and Comparative Examples 1-7 was analyzed and tested. The test method was as follows: micropores and mesopores were analyzed using a Micropore Analyzer, and the ratio of micropores to mesopores was determined using the instrument's built-in DFT micropore analysis software. The test results are shown in Table 1.
[0123] Table 1. Some preparation parameters and precursor pore size analysis results of Examples 1-9 and Comparative Examples 1-7
[0124]
[0125]
[0126] The precursors obtained in Example 1 and Comparative Examples 1-2 were subjected to morphological testing. The powder was placed on a metal conductive sample stage, and a small portion of the powder was adhered with conductive adhesive. Gold was then sputtered onto the powder, and SEM images were taken. The SEM images are shown in Tables 1-3. Figure 1 Here is an electron microscope image of the precursor prepared in Comparative Example 1. Figure 2 Here is an electron microscope image of the precursor prepared in Comparative Example 2. Figure 3 Electron micrograph of the precursor prepared in Example 1.
[0127] From Table 1 and Figure 1-3 As can be seen from the embodiments of the present invention, the precursor obtained by the preparation method has a porous MOF-like structure with a high proportion of mesopores, which can effectively disperse nickel salt precipitates and thus improve the performance of the electrode material. In Comparative Example 1, tert-butanol was used as a ligand, and the resulting precursor had a solid structure with small pore size. In Comparative Example 2, the ratio of zirconium salt to ligand was not ideal, and the resulting precursor had a plate-like structure with poor pore structure.
[0128] The hydrogen electrode materials prepared in Examples 1-3, 10-21 and Comparative Examples 2-3 and 8-11 were characterized and tested, as follows:
[0129] a) Laser particle size: The obtained hydrogen electrode material powder was tested using a laser particle size analyzer, with a standard size of 0.02 μm. <D50<0.05μm。
[0130] b) Conductivity: The hydrogen electrode material powder was ground, and 1 wt% PVA glue was added relative to the powder mass. The powder was ground until uniform. Then, a specific pressing mold was used to press the powder into a cuboid shape and placed in a muffle furnace. After calcination at 1300℃ for 2 hours, the powder was allowed to cool naturally to room temperature. The intrinsic conductivity of the material was then tested using a DC four-terminal method at 700℃. The acceptable range was 200-300 S / cm.
[0131] c) Impedance Testing: Hydrogen electrode and oxygen electrode material powders were prepared into a hydrogen electrode slurry, printed onto the electrolyte surface, and sintered at 1300℃ for 2.5 hours to obtain a half-cell. Leads were pre-soldered to the positive and negative electrodes of the electrolytic cell using silver paste. The stack temperature was stabilized at 800℃. The hydrogen electrode was reduced by passing 30% humidified hydrogen gas. After reaching a stable state, specified performance tests were performed. An impedance meter was connected to the leads, with a sampling interval of 1 second. The number of samples per measurement was 30, and the number of repetitions was 5. The acceptable range was 200-700 mΩ·cm. 2 .
[0132] The test results are shown in Table 2.
[0133] Table 2. Some preparation parameters and performance test results of Examples 1-3, 10-21 and Comparative Examples 2-3, 8-11
[0134]
[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.
Claims
1. A method for preparing a hydrogen electrode material, characterized in that, Includes the following steps: S1. Prepare a mixed solution A containing zirconium salt and yttrium salt, and prepare a mixed solution B containing ligand. After mixing the mixed solution A and the mixed solution B, adjust the pH of the solution to acidic, carry out a hydrothermal reaction, wash, and dry to obtain the precursor. The ligand includes at least one of terephthalic acid, trimesic acid, and bipyridine; S2. Add alkali to the nickel salt solution to adjust the pH of the solution to be greater than 10, separate and wash the solid to obtain nickel salt precipitate; S3. Mix the nickel salt precipitate obtained in step S2 with the precursor obtained in step S1, add hydration slurry to obtain mixture C, and then separate the solid and liquid components of the mixture C to obtain the product precipitate. S4. Calcine the precipitate obtained in step S3 to obtain the hydrogen electrode material.
2. The method for preparing the hydrogen electrode material according to claim 1, characterized in that, In step S1, the molar ratio of the zirconium salt to the ligand is 1:(1-4).
3. The method for preparing the hydrogen electrode material according to claim 1, characterized in that, In step S1, the temperature of the hydrothermal reaction is 100℃-150℃, and the time is 20h-30h.
4. The method for preparing the hydrogen electrode material according to claim 1, characterized in that, In step S1, the zirconium salt includes at least one of zirconium chloride, zirconium nitrate, and zirconium sulfate; and / or, the yttrium salt includes at least one of yttrium chloride, yttrium nitrate, and yttrium sulfate; and / or, in step S1, the drying is performed under vacuum at a temperature of 130°C-150°C for 5-8 hours; and / or, in step S2, the nickel salt includes at least one of nickel nitrate, nickel chloride, and nickel sulfate.
5. The method for preparing the hydrogen electrode material according to claim 1, characterized in that, The molar ratio of nickel in the nickel salt in step S2 to zirconium in the zirconium salt in step S1 is 1.7:1-7:
1.
6. The method for preparing the hydrogen electrode material according to claim 1, characterized in that, In step S2, the D50 particle size of the nickel salt precipitate is 0.01 μm-0.06 μm.
7. The method for preparing the hydrogen electrode material according to claim 1, characterized in that, In step S3, the temperature during pulping is 50℃-120℃.
8. The method for preparing the hydrogen electrode material according to claim 1, characterized in that, In step S4, the calcination temperature is 240℃-400℃, and the calcination time is 2h-4h.
9. The hydrogen electrode material prepared by the method of any one of claims 1-8.
10. The application of the hydrogen electrode material according to claim 9 in a solid oxide electrolyzer.