High-entropy perovskite oxygen electrode material and preparation method and application thereof

Abstract

This invention relates to a high-entropy perovskite oxygen electrode material, its preparation method, and its application. The chemical formula of the high-entropy perovskite oxygen electrode material is ABO. 3‑δ The high-entropy perovskite oxygen electrode material comprises at least lanthanum and strontium at site A, and optionally also comprises one or more other elements selected from rare earth metals, alkaline earth metals, or transition metals, specifically praseodymium, yttrium, barium, calcium, magnesium, and copper; site B comprises at least cobalt and iron, and optionally also comprises one or more other elements selected from rare earth metals, alkaline earth metals, or transition metals, specifically praseodymium, yttrium, barium, calcium, and copper; δ represents the oxygen vacancy content. The high-entropy perovskite oxygen electrode material is prepared by a sol-gel method. Compared with existing technologies, the high-entropy perovskite oxygen electrode material of this invention exhibits excellent stability, effectively suppresses cation segregation, and has high electrochemical activity.

Description

Technical Field

[0001] This invention relates to the field of solid oxide fuel cells and solid oxide electrolyzers, and in particular to a high-entropy perovskite oxygen electrode material, its preparation method, and its application. Background Technology

[0002] Solid oxide fuel cells (SOFCs) are a new generation of high-temperature electrochemical energy conversion devices that use solid oxides as electrolytes to directly generate electricity through the electrochemical reaction of fuels (such as hydrogen and natural gas) with oxygen. Their advantages include wide fuel adaptability, high power generation efficiency, no precious metal catalysts, and low emissions, and they have been used in distributed power generation, transportation power, and other fields. Solid oxide electrolyzers (SOECs) are the reverse process of SOFCs, utilizing high-temperature electrolysis of water vapor or carbon dioxide to convert electrical energy into hydrogen or syngas. They offer high electrolysis efficiency and are suitable for renewable energy hydrogen production and carbon dioxide resource utilization. However, in current SOFC / SOEC systems, during long-term operation, cations tend to migrate into the electrolyte, forming an insulating phase, leading to a surge in ohmic resistance and thus shortening battery life. Therefore, finding efficient and stable oxygen electrode materials is of great significance for the development of SOFC / SOECs.

[0003] A common oxygen electrode material is perovskite ABO3. The A-site typically contains an alkaline earth metal or rare earth metal, while the B-site is generally a transition metal. This structure endows perovskite oxides with excellent properties such as high ionic conductivity, high stability, and tunable magnetism. Furthermore, perovskite ABO3 materials offer advantages such as not requiring precious metals and having a coefficient of thermal expansion that matches that of the electrolyte material. However, perovskite materials exhibit poor catalytic and conductive properties, necessitating modification through doping or loading with transition metal oxides. By adjusting the types and ratios of A-site and B-site ions, their electrochemical performance can be further optimized.

[0004] Therefore, there is an urgent need to develop an oxygen electrode material with excellent electrochemical activity and stability. Summary of the Invention

[0005] The purpose of this invention is to provide a high-entropy perovskite oxygen electrode material, its preparation method, and its application. The high-entropy perovskite oxygen electrode material has excellent electrochemical stability, can effectively suppress cation segregation, and has high electrochemical activity.

[0006] The objective of this invention can be achieved through the following technical solutions: One objective of this invention is to provide a high-entropy perovskite oxygen electrode material with the general chemical formula ABO. 3-δThe A-site contains at least lanthanum and strontium, and optionally also contains one or more other elements selected from rare earth metals, alkaline earth metals, or transition metals, specifically one or more of praseodymium, yttrium, barium, calcium, magnesium, and copper; the B-site contains at least cobalt and iron, and optionally also contains one or more other elements selected from rare earth metals, alkaline earth metals, or transition metals, specifically one or more of praseodymium, yttrium, barium, calcium, and copper; δ represents the oxygen vacancy content, with a value ranging from 0 to 1.

[0007] More preferably, the other elements in position A and the other elements in position B are selected independently.

[0008] More preferably, the chemical formula of the high-entropy perovskite oxygen electrode material is (A 1-x La x Sr 0.4 (B) 1- y Co 0.2 Fe y )O 3-δ Where 0.4≤x≤0.6, 0.2≤y≤0.8, and 0<δ<1.

[0009] Preferably, the high-entropy perovskite oxygen electrode material has a typical hexagonal unit cell R-3C.

[0010] Preferably, the chemical formula of the high-entropy perovskite oxygen electrode material includes any of the following: La 0.6 Sr 0.4 (Co 0.2 Fe 0.2 Pr 0.2 Y 0.2 Ba 0.2 )O 3-δ ; La 0.4 (Pr 0.04 Y 0.04 Ba 0.04 Ca 0.04 Cu 0.04 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ ; La 0.6 Sr 0.4 Co 0.2 Fe 0.6 (Pr 0.04 Y 0.04 Ba 0.04 Ca 0.04 Cu 0.04 )O3-δ .

[0011] Preferably, La 0.6 Sr 0.4 (Co 0.2 Fe 0.2 Pr 0.2 Y 0.2 Ba 0.2 )O 3-δ In this array, the A-site ions are La (lanthanum) and Sr (strontium), and the B-site ions are Co (cobalt), Fe (iron), Pr (praseodymium), Y (yttrium) and Ba (barium).

[0012] Preferably, La 0.4 (Pr 0.04 Y 0.04 Ba 0.04 Ca 0.04 Cu 0.04 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ In this system, the A-site ions are La (lanthanum), Pr (praseodymium), Y (yttrium), Ba (barium), Ca (calcium), Cu (copper), and Sr (strontium), while the B-site ions are Co (cobalt) and Fe (iron).

[0013] Preferably, La 0.6 Sr 0.4 Co 0.2 Fe 0.6 (Pr 0.04 Y 0.04 Ba 0.04 Ca 0.04 Cu 0.04 )O 3-δ In this system, the A-site ions are La (lanthanum) and Sr (strontium), and the B-site ions are Co (cobalt), Fe (iron), Pr (praseodymium), Y (yttrium), Ba (barium), Ca (calcium), and Cu (copper).

[0014] Preferably, the configurational entropy ΔS of the high-entropy perovskite oxygen electrode material is... config Satisfy: ΔS config >1.5R, where R is the ideal gas constant.

[0015] Preferably, the high-entropy perovskite oxygen electrode material is prepared by the sol-gel method.

[0016] The second objective of this invention is to provide a method for preparing a high-entropy perovskite oxygen electrode material, comprising the following steps: S1: Weigh the corresponding metal nitrates of each element according to the stoichiometric ratio in the high-entropy perovskite oxygen electrode material and dissolve them in deionized water, then mix them evenly to obtain solution A. S2: Prepare solution B; S3: Transfer the B solution to the A solution to obtain a reaction solution, and adjust the pH to weakly alkaline; S4: Heat and stir the reaction solution to obtain a gel; S5: The gel is heated at high temperature to obtain a black precursor; S6: The black precursor is sintered to obtain the high-entropy perovskite oxygen electrode material.

[0017] Preferably, in step S1, the concentration range of each metal nitrate solution in solution A is 40-90 wt%.

[0018] Preferably, in step S2, the solution B is a mixed solution of ethylenediaminetetraacetic acid-citric acid-ammonia water or a mixed solution of anhydrous ethanol-citric acid.

[0019] More preferably, in step S2, when the solution B is a mixed solution of ethylenediaminetetraacetic acid, citric acid, and ammonia, the concentration of ethylenediaminetetraacetic acid is 5-15 wt%, the concentration of citric acid is 8-16 wt%, and the concentration of ammonia is 10-25 wt%.

[0020] More preferably, in step S2, when the solution B is an ethanol-citric acid mixed solution, the concentration of ethanol is 70-95 wt% and the concentration of citric acid is 10-16 wt%.

[0021] Preferably, in step S3, when the solution B is a mixed solution of ethylenediaminetetraacetic acid, citric acid, and ammonia, the total molar amount of cations in each metal salt in the reaction solution and the molar ratio of ethylenediaminetetraacetic acid to citric acid are 1:1-3:1-2.

[0022] Preferably, in step S3, when the solution B is an anhydrous ethanol-citric acid mixed solution, the total molar amount of cations in each metal salt and the molar ratio of ethanol to citric acid are 1:1-2:1-3.

[0023] Preferably, in step S3, the pH of the reaction solution is adjusted to 8-9.

[0024] Preferably, in step S4, the heating and stirring temperature is 60℃-90℃, the time is 4-24 hours, and the stirring speed is 200-600 rpm.

[0025] More preferably, in step S4, the heating and stirring are carried out using a water bath heating method.

[0026] More preferably, in step S4, the temperature of the heating and stirring is 60℃-80℃.

[0027] Preferably, in step S5, the high-temperature heating refers to heating at 500℃-650℃ for 3-7 hours to remove moisture, nitrates and organic matter.

[0028] More preferably, in step S5, the high-temperature heating refers to heating at 500℃-600℃ for 3-7 hours.

[0029] Preferably, in step S6, the sintering treatment refers to maintaining a sintering temperature of 1200℃-1350℃ for 3-7 hours.

[0030] More preferably, in step S6, the sintering is carried out in a muffle furnace.

[0031] The third objective of this invention is to provide an application of a high-entropy perovskite oxygen electrode material, which is used as an oxygen electrode in a solid oxide fuel cell or a solid oxide electrolyzer.

[0032] High-entropy materials are materials composed of five or more elements, typically in equimolar or near-equimolar compositions. According to the definition of high-entropy materials: ΔS config Materials with a value greater than 1.5R are considered high-entropy. Based on the relationship between Gibbs free energy, enthalpy change, and entropy change: ΔG mix =ΔH mix -TΔS mix When ΔG mix A stable homogeneous phase is only achieved when the density is reduced. At this point, introducing multiple elements into the system increases its disorder, thereby increasing the system's configuration entropy (Sconfig). When ΔS... config When ΔG increases, mix The more negative the value, the better the stability of the compound.

[0033] This invention designs a high-entropy perovskite material with the structural formula (A 1-x La x Sr 0.4 (B) 1-y Co 0.2 Fe y )O 3-δ , 0 < δ < 1, 0.4 ≤ x ≤ 0.6, 0.2 ≤ y ≤ 0.8. This material uses LSCF (La... 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ Based on this, by introducing different elements at the A and B sites for substitution, various ΔS values ​​were prepared. configHigh-entropy materials with a refractive index > 1.5R. Furthermore, the performance of three high-entropy materials with different doping sites—LSCFPYB, L(PYBCC)SCF, and LSCF(PYBCC)—as oxygen electrodes in SOFC / SOEC was compared to investigate the influence of different high-entropy doping sites on material properties.

[0034] Compared with the prior art, the present invention has the following beneficial effects: (1) In order to solve the problems of cation segregation and insufficient stability of existing SOFC / SOEC oxygen electrode materials, this invention provides a method for preparing high-entropy perovskite oxygen electrode materials. By introducing multiple metal elements at the A or B site of the perovskite material, a high-entropy oxygen electrode material is formed, which further increases the configuration entropy and improves the stability, thereby suppressing the cation segregation problem and improving the electrochemical activity of the oxygen electrode.

[0035] (2) In this invention, the A site or B site is occupied by multiple metal ions, forming a high configuration entropy, which inhibits element diffusion and phase separation, suppresses cation segregation problems, and significantly improves the thermal and chemical stability of the material at high temperature (800℃).

[0036] (3) In this invention, the combination of multi-element doping at A site or B site can regulate lattice distortion, promote the formation and migration of oxygen vacancies, and enhance oxygen ion conduction ability, which is crucial for the oxygen electrode reaction of SOFC / SOEC.

[0037] (4) In this invention, the disordered arrangement of A-site and B-site elements effectively suppresses strontium segregation during electrolysis, improves the long-term stability of the electrode, and increases the mechanical strength of the material. In a 100-hour long-term test of the LSCFPYB high-entropy oxygen electrode material, whether in SOFC mode or SOEC mode, it showed good cation segregation suppression performance and excellent long-term operational stability.

[0038] (5) Experiments show that the oxygen electrode LSPYBCF with high entropy at the B site has a more significant performance improvement than other materials. Attached Figure Description

[0039] Figures 1-3 The images shown are, in order, the refined XRD Rietveld images of the three high-entropy perovskite oxygen electrode materials in Examples 1-3.

[0040] Figure 4 These are XPS full spectra of the three high-entropy perovskite oxygen electrode materials in Examples 1-3 (a: LSCFPYB; b: L(PYBCC)SCF; c: LSCF(PYBCC)).

[0041] Figure 5The XPS:O 1s spectra of the three high-entropy perovskite oxygen electrode materials in Examples 1-3 are shown (a: LSCFPYB; b: L(PYBCC)SCF; c: LSCF(PYBCC)).

[0042] Figure 6 The thermogravimetric analysis curves are those of the three high-entropy perovskite oxygen electrode materials in Examples 1-3 and the LSCF material in Comparative Example 1.

[0043] Figures 7-9 The images shown are, in order, TEM images and elemental distribution diagrams of the three high-entropy perovskite oxygen electrode materials in Examples 1-3 (in each image, a: TEM; b: lattice fringe analysis; c: elemental distribution diagram).

[0044] Figures 10-13 The following are, in order, the current density-voltage-power density and impedance diagrams of the three high-entropy perovskite oxygen electrode materials in Examples 1-3 and the LSCF material in Comparative Example 1, using 97% H2 + 3% H2O as fuel (in each diagram, a: current density-voltage-power density diagram, b: impedance diagram).

[0045] Figure 14 This is a long-term operational stability diagram of the high-entropy perovskite oxygen electrode material LSCFPYB (in the figure, a: SOFC; b: SOEC). Detailed Implementation

[0046] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0047] Unless otherwise specified, the reagents, methods, instruments, and equipment used in this invention are conventional in the art. Unless otherwise specified, the reagents and materials used in the following examples are all commercially available.

[0048] Example 1 Weigh out 12.990g of lanthanum nitrate hexahydrate, 4.232g of strontium nitrate, 4.350g of praseodymium nitrate hexahydrate, 3.830g of yttrium nitrate hexahydrate, 2.613g of barium nitrate, 2.910g of cobalt nitrate hexahydrate, and 4.040g of ferric nitrate nonahydrate according to the stoichiometric ratio of the metal elements. Dissolve them in deionized water and mix thoroughly to obtain solution A. Dissolve ethylenediaminetetraacetic acid, citric acid, and ammonia in water to obtain solution B. Then pour solution B into solution A to obtain a mixed solution. The molar ratio of cations in the metal salt solution of the mixed solution to ethanol and citric acid is 1:1:2. Add ammonia to adjust the pH of the solution to 8-9. Keep the solution at 100℃ on a magnetic heating plate and stir slowly to dry the moisture until gelation. Incubate the gel at 700℃ for 5 hours to remove organic matter and moisture, obtaining a black sponge-like solid precursor. The black precursor was placed in a muffle furnace and sintered at 1200℃ for 6 hours to obtain a perovskite oxygen electrode material with high entropy design at the B site, La. 0.6 Sr 0.4 (Co 0.2 Fe 0.2 Pr 0.2 Y 0.2 Ba 0.2 )O 3-δ , abbreviated as LSCFPYB.

[0049] Example 2 Weigh out 8.660g of lanthanum nitrate hexahydrate, 0.870g of praseodymium nitrate hexahydrate, 0.766g of yttrium nitrate hexahydrate, 0.523g of barium nitrate, 0.328g of calcium nitrate, 0.375g of copper nitrate, 4.232g of strontium nitrate, 2.910g of cobalt nitrate hexahydrate, and 16.160g of ferric nitrate nonahydrate according to the stoichiometric ratio of the metal elements. Dissolve them in deionized water and mix thoroughly to obtain solution A. Dissolve ethylenediaminetetraacetic acid, citric acid, and ammonia in water to obtain solution B. Then pour solution B into solution A to obtain a mixed solution. The molar ratio of cations in the metal salt solution of the mixed solution to ethanol and citric acid is 1:1:1.5. Add ammonia to adjust the pH of the solution to 8-9. Keep the solution at 100°C on a magnetic heating plate and stir slowly to dry the moisture until gelation. The gel was heated at 650 °C for 5 hours to remove organic matter and moisture, yielding a black, sponge-like solid precursor. The black precursor was then placed in a muffle furnace and sintered at 1300 °C for 6 hours to obtain a perovskite oxygen electrode material doped with high-entropy elements at the A-site, La. 0.4 (Pr 0.04 Y 0.04 Ba 0.04 Ca 0.04 Cu 0.04 Sr 0.4 Co 0.2 Fe 0.8 O 3-δIt is abbreviated as L(PYBCC)SCF.

[0050] Example 3 Weigh out 12.990g of lanthanum nitrate hexahydrate, 4.232g of strontium nitrate, 2.910g of cobalt nitrate hexahydrate, 12.120g of ferric nitrate nonahydrate, 0.870g of praseodymium nitrate hexahydrate, 0.766g of yttrium nitrate hexahydrate, 0.523g of barium nitrate, 0.328g of calcium nitrate, and 0.375g of copper nitrate according to the stoichiometric ratio of the metal elements. Dissolve them in deionized water and mix thoroughly to obtain solution A. Dissolve ethylenediaminetetraacetic acid, citric acid, and ammonia in water to obtain solution B. Then pour solution B into solution A to obtain a mixed solution. The molar ratio of cations in the metal salt solution of the mixed solution to ethanol and citric acid is 1:1:1.5. Add ammonia to adjust the pH of the solution to 8-9. Keep the solution at 100°C on a magnetic heating plate and stir slowly to dry the moisture until gelation. The gel was heated at 700℃ for 5 hours to remove organic matter and moisture, yielding a black, sponge-like solid precursor. The black precursor was then placed in a muffle furnace and sintered at 1200℃ for 6 hours to obtain a perovskite oxygen electrode material doped with high-entropy elements at the B site, La. 0.6 Sr 0.4 Co 0.2 Fe 0.6 (Pr 0.04 Y 0.04 Ba 0.04 Ca 0.04 Cu 0.04 )O 3-δ It is abbreviated as LSCF (PYBCC).

[0051] Comparative Example 1 Ordinary LSCF material, purchased from Ningbo Sofor Energy Technology Co., Ltd.

[0052] like Figures 1-3 As shown in Table 1, XRD characterization confirms that the materials obtained in Examples 1-3 are all high-entropy perovskite materials. The ΔS values ​​of the three high-entropy materials obtained in Examples 1-3 are... config Both are greater than 1.5R, and the ΔS of the B-site high-entropy perovskite materials LSCFPYB and LSCF(PYBCC) are greater than 1.5R. config It is significantly greater than that of the A-site high-entropy perovskite material L(PYBCC)SCF.

[0053] Table 1 like Figure 4 As shown, the metal element peaks in the three high-entropy materials obtained in Examples 1-3 can all be found in the XPS full-image, further proving their successful preparation.

[0054] like Figure 5As shown, the adsorbed oxygen ratios of the three high-entropy materials obtained in Examples 1-3 were 58.27%, 56.53%, and 57.80%, respectively. The adsorbed oxygen ratio of LSCFPYB was higher than that of the other two high-entropy materials, and adsorbed oxygen is usually related to the oxygen vacancy content.

[0055] like Figure 6 As shown, the thermogravimetric loss of the three high-entropy materials is higher than that of the ordinary LSCF material (1.07%), while the weight loss of LSCFPYB is the most significant, with a total mass loss of 1.20%, which is significantly higher than the other two high-entropy materials, indicating that it has a higher oxygen vacancy content.

[0056] like Figures 7-9 As shown, HRTEM lattice fringe analysis revealed that all three materials exhibited a clear and continuous lattice arrangement, confirming that the high-entropy process did not disrupt the integrity and periodicity of the perovskite ABO3 type. Precise measurements of the characteristic crystal planes (1-10) are as follows: the interplanar spacing of the B-site high-entropy doped LSCFPYB is approximately 0.276 nm, the interplanar spacing of LSCF(PYBCC) is 0.280 nm, and the interplanar spacing of the A-site high-entropy doped L(PYBCC)SCF and LSCF(PYBCC) increases to 0.282 nm. The interplanar spacing increases with the increase of the dopant element at the A-site. Elemental surface scan analysis further revealed the distribution characteristics of multiple elements: in the three materials, the surface distribution signals of the doped elements highly overlap spatially, with no obvious local enrichment or agglomeration regions, indicating that each element is uniformly dispersed in the lattice sites.

[0057] like Figures 10-13 As shown, electrochemical performance tests were conducted within the temperature range of 650-800 °C, using wet hydrogen (97% H2 + 3% H2O) as fuel and air as oxidant to simulate a real fuel environment. Among them, the LSCFPYB material with high entropy design at the B-site exhibited the best performance: its maximum power density reached 300.82 mW·cm at test temperatures of 650 °C, 700 °C, 750 °C, and 800 °C, respectively. -2 496.40 mW·cm -2 689.62 mW·cm -2 and 945.08 mW·cm -2 The entropy is significantly higher than that of the other two high-entropy materials and the control materials (A-site doped L(PYBCC)SCF, B-site doped LSCF(PYBCC) and LSCF). Taking 800 °C as an example, LSCFPYB (945.08 mW·cm⁻¹) -2 The maximum power density of ) is higher than that of L(PYBCC)SCF (773.76 mW·cm). -2 ), LSCF(PYBCC) (834.30 mW·cm-2 ) and LSCF (569.72 mW·cm -2 The results show a certain improvement, demonstrating the significant performance gain brought about by B-site high entropy doping. This result reveals the differential regulatory effect of different lattice site doping on the catalytic activity of SOFCs. The B-site high entropy design effectively improves the energy conversion efficiency of the battery by optimizing the contact characteristics of the oxygen electrode and electrolyte interface. Its performance gain mechanism can be attributed to the enhanced catalytic activity and the reduction of interfacial impedance.

[0058] The LSCFPYB designed for position B exhibits an Rp value of 1.47 Ω·cm at 650–800 °C. 2 0.78 cm 2 0.43 cm 2 and 0.24 Ω·cm 2 The Rp performance of this material is significantly superior to that of L(PYBCC)SCF, LSCF(PYBCC), and LSCF, which are doped with high entropy at both the A and B sites. It is noteworthy that the polarization resistance of oxygen electrode materials primarily stems from oxygen ion transport resistance, and oxygen vacancies are the core carriers of oxygen ion transport. High-entropy materials enhance electrochemical performance mainly through a dual approach of lattice distortion and structural modulation.

[0059] like Figure 14 As shown, in the long-term test of the LSCFPYB high-entropy oxygen electrode material, under the experimental conditions of 800 ℃, fuel gas (3% H2O + 97% H2) and 0.8 V operating voltage, the current density increased from the initial 666.89 mA·cm⁻¹ in 100 hours. -2 Decreased to 664.76 mA·cm -2 The corresponding attenuation rate is approximately 0.32%, indicating that the material exhibits good power generation stability under high temperature and high humidity conditions. In the long-term stability test in SOEC mode, the experimental conditions were 800 ℃, feed gas (60% H2O + 40% N2), and 1.0 A·cm⁻¹. -2 At constant current density, the battery voltage dropped from 1.413 V to 1.402 V within 100 hours of operation, with a degradation rate of approximately 0.78%. This demonstrates the good stability of the B-site high-entropy perovskite material.

[0060] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A high-entropy perovskite oxygen electrode material, characterized in that, Its general chemical formula is ABO 3-δ The A-site contains at least lanthanum and strontium, and optionally also contains one or more other elements selected from rare earth metals, alkaline earth metals, or transition metals, specifically one or more of praseodymium, yttrium, barium, calcium, magnesium, and copper; the B-site contains at least cobalt and iron, and optionally also contains one or more other elements selected from rare earth metals, alkaline earth metals, or transition metals, specifically one or more of praseodymium, yttrium, barium, calcium, and copper; δ represents the oxygen vacancy content, with a value ranging from 0 to 1.

2. The high-entropy perovskite oxygen electrode material according to claim 1, characterized in that, The chemical formula of the high-entropy perovskite oxygen electrode material includes any of the following: Day 0.6 Sr 0.4 (Co 0.2 Feb 0.2 Prof 0.2 Y 0.2 Ba 0.2 )O 3-δ ; Day 0.4 (Pr 0.04 Y 0.04 Ba 0.04 Approx 0.04 Cu 0.04 ) Mr 0.4 Co 0.2 Feb 0.8 O 3-δ ; Day 0.6 Sr 0.4 Co 0.2 Feb 0.6 (Pr 0.04 Y 0.04 Ba 0.04 Approx 0.04 Cu 0.04 )O 3-δ .

3. A method for preparing a high-entropy perovskite oxygen electrode material according to any one of claims 1-2, characterized in that, Includes the following steps: S1: Weigh the corresponding metal nitrates of each element according to the stoichiometric ratio in the high-entropy perovskite oxygen electrode material and dissolve them in deionized water, then mix them evenly to obtain solution A. S2: Prepare solution B; S3: Transfer the B solution to the A solution to obtain a reaction solution, and adjust the pH to weakly alkaline; S4: Heat and stir the reaction solution to obtain a gel; S5: The gel is heated at high temperature to obtain a black precursor; S6: The black precursor is sintered to obtain the high-entropy perovskite oxygen electrode material.

4. The method for preparing the high-entropy perovskite oxygen electrode material according to claim 3, characterized in that, In step S1, the concentration range of each metal nitrate solution in solution A is 40-90 wt%.

5. The method for preparing the high-entropy perovskite oxygen electrode material according to claim 3, characterized in that, In step S2, solution B is either a mixed solution of ethylenediaminetetraacetic acid (EDTA), citric acid, and ammonia, or a mixed solution of ethanol and citric acid. When solution B is an EDTA-citric acid-ammonia solution, the concentration of EDTA is 5-15 wt%, the concentration of citric acid is 8-16 wt%, and the concentration of ammonia is 10-25 wt%. When solution B is an ethanol-citric acid solution, the concentration of ethanol is 70-95 wt%, and the concentration of citric acid is 10-16 wt%.

6. The method for preparing the high-entropy perovskite oxygen electrode material according to claim 3, characterized in that, In step S3, when solution B is a mixed solution of ethylenediaminetetraacetic acid, citric acid, and ammonia, the total molar amount of cations in each metal salt in the reaction solution and the molar ratio of ethylenediaminetetraacetic acid to citric acid are 1:1-3:1-2; when solution B is a mixed solution of ethanol and citric acid, the total molar amount of cations in each metal salt and the molar ratio of ethanol to citric acid are 1:1-2:1-3; the pH of the reaction solution is adjusted to 8-9.

7. The method for preparing the high-entropy perovskite oxygen electrode material according to claim 3, characterized in that, In step S4, the heating and stirring temperature is 60℃-90℃, the time is 4-24 hours, the stirring speed is 200-600 rpm, and the heating and stirring adopts a water bath heating method.

8. The method for preparing the high-entropy perovskite oxygen electrode material according to claim 3, characterized in that, In step S5, the high-temperature heating refers to heating at 500℃-650℃ for 3-7 hours.

9. The method for preparing the high-entropy perovskite oxygen electrode material according to claim 3, characterized in that, In step S6, the sintering treatment refers to maintaining the temperature at 1200℃-1350℃ for 3-7 hours.

10. An application of the high-entropy perovskite oxygen electrode material according to any one of claims 1-2, characterized in that, The high-entropy perovskite oxygen electrode material is used as an oxygen electrode in solid oxide fuel cells or solid oxide electrolyzers.

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