High-performance proton ceramic fuel cell heterostructure cathode material and preparation method thereof

Abstract

The application relates to the field of proton ceramic fuel cells, and provides a high-performance proton ceramic fuel cell heterogeneous structure cathode material and a preparation method thereof. 2‑ x Zr x O 5+δ , wherein Ln=La, Pr, Sm, Gd or Eu, 0.04<=x<=0.5, and delta is the non-stoichiometry of oxygen. The cathode material provided by the application comprises: a substrate (Ln 1 / (2‑x) Ba (1‑x) / (2‑x) )2Co2O 5+δ and BaZrO3 nanoparticles precipitated and anchored on the surface of the substrate. The material LnBaCo2O 5+δ is doped with element Zr at the B site, so that the BaZrO3 nanoparticles are in-situ desolvated and anchored on the surface of the substrate in a high-temperature oxidizing atmosphere, forming an ion-electron mixed conductor and a proton conductor heterogeneous structure, which makes the nano-composite cathode material have a triple electric conduction (oxygen ion-proton-electron) reaction region, also has good oxygen reduction catalytic activity, excellent chemical and structural stability, and is a universal method for preparing excellent proton ceramic fuel cell cathode materials.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of proton ceramic fuel cells, in particular to a high-performance proton ceramic fuel cell heterostructure cathode material and a preparation method thereof. TECHNICAL BACKGROUND

[0002] Proton ceramic fuel cells (PCFC) adopt a full solid-state structure and work at a medium-low temperature (450-700 DEG C), and are a clean and efficient energy conversion device, which can directly convert chemical energy into electrical energy and is not limited by Carnot cycle, and has high energy conversion efficiency. The PCFC is composed of an anode, an electrolyte and a cathode, and the three are tightly connected together through high-temperature sintering. The electrode adopts a porous structure, is beneficial to gas transmission, and has certain conductivity and catalytic activity. The anode, namely the fuel electrode, is a place where hydrogen or other fossil fuels are catalytically dissociated and oxidized to generate hydrogen ions; oxygen is adsorbed and dissociated to electrons in the cathode and is reduced to oxygen ions; the electrolyte adopts a dense structure, has high ion conductivity and electron insulation, and is located between the anode and the cathode, and is responsible for isolating the two electrodes while transmitting oxygen ions and protons.

[0003] The main polarization loss of the PCFC comes from the cathode, and the electrochemical performance of the PCFC is limited to a large extent by the slow oxygen reduction reaction kinetics of the cathode material at medium temperature. The PCFC cathode material system is limited, and the current main application systems are BaZr 0.6 Co 0.4 O3, BaZr 0.2 Co 0.4 Fe 0.4 O 3-δ , BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ , NdBa 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5+δ and PrBa 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5+δ . The cathode of the PCFC is usually extended from the oxygen ion conductor solid oxide fuel cell (O-SOFC) cathode, and the material is mostly an oxygen ion-electron mixed conductor (MIEC), but the MIEC lacks proton conductivity, resulting in poor electrochemical performance of the battery. Therefore, the MIEC material can be introduced into the proton conductivity to become an oxygen ion-proton-electron triple conductor (TCOs), so as to improve the catalytic activity and performance of the PCFC.

[0004] Cobalt-based double perovskite oxide LnBaCo2O 5+δ The material is an excellent MIECs material, has a high oxygen surface exchange coefficient and bulk diffusion coefficient, and exhibits excellent oxygen reduction catalytic performance, and is a research hotspot of cathode materials. 5+δ It is a problem to be solved to introduce proton conductivity into the material, improve the electrochemical performance, and at the same time, maintain good structural stability, stability in a water-containing atmosphere, and durability. SUMMARY

[0005] In view of this, the present application introduces Zr element doping into the B site of the LnBaCo2O 5+δ The method for in-situ desolubilization of a proton-conducting perovskite oxide from the material B site doped with Zr element in a high-temperature oxidation atmosphere aims to provide a high-performance proton ceramic fuel cell heterostructure cathode material. The cathode material provided by the present application has high ORR (oxygen reduction reaction) catalytic activity, excellent chemical and structural stability, and good durability.

[0006] One aspect of the present application provides a high-performance proton ceramic fuel cell heterostructure cathode material, which is LnBaCo2O 5+δ The B site of the system is doped with Zr element to form a cathode material with a chemical formula of LnBaCo 2-x Zr x O 5+δ ; wherein Ln = La, Pr, Sm, Gd or Eu, 0.04≤x≤0.5, and δ is a non-stoichiometric oxygen; the cathode material comprises a substrate and a perovskite oxide precipitated and anchored on the surface of the substrate, the substrate is (Ln 1 / (2-x) Ba (1-x) / (2-x) )2Co2O 5+δ , and the perovskite oxide is BaZrO3.

[0007] Preferably, the cathode material is LnBaCo 1.96 Zr 0.04 O 5+δ , LnBaCo 1.92 Zr 0.08 O 5+δ , or LnBaCo 1.88 Zr 0.12 O 5+δ .

[0008] Preferably, the cathode material is LnBaCo2O 5+δ The B site of the system is co-doped with Zr, Y elements or co-doped with Zr, Ce, Y elements to generate cubic phase BaZr 1-A-B Ce A YB O3, where 0 ≤ A < 1, 0 <B<1。

[0009] Another aspect of the present invention provides a method for preparing the proton ceramic fuel cell cathode material as described above, comprising:

[0010] A) Dissolve Ln salt, Ba salt, Co salt and Zr salt in dilute acid, add chelating agent, adjust pH value, stir reaction to obtain reaction mixture;

[0011] B) Heating the reaction mixture to prepare a precursor;

[0012] C) The precursor is calcined to obtain the proton ceramic fuel cell cathode material.

[0013] Preferably, in step A), the Ln salt is Ln(NO3)3·6H2O, the Ba salt is Ba(NO3)2, the Co salt is Co(NO3)2·6H2O, and the Zr salt is Zr(NO3)4·5H2O; the chelating agent is citric acid and ethylenediaminetetraacetic acid; and the dilute acid is 10-30 wt% nitric acid.

[0014] More preferably, the ratio of the total amount of metal ions in the Ln salt, Ba salt, Co salt and Zr salt to citric acid and ethylenediaminetetraacetic acid is 1:1.5:1.

[0015] Preferably, the pH adjustment is achieved by adding ammonia to adjust the pH to 7; the stirring reaction time is 1-2 hours.

[0016] Preferably, in step B), heating the reaction mixture specifically includes: heating the reaction mixture to auto-ignition and continuing to heat until the combustion reaction is complete, wherein the temperature at which the auto-ignition reaction occurs is preferably 120–300°C.

[0017] Preferably, in step C), the calcination temperature is 1000–1200°C, and the calcination time is 2–3 hours.

[0018] Preferably, in step A), Y salt, or Y salt and Ce salt, are also added to LnBaCo2O 5+δ The system is co-doped with Zr and Y elements at the B site, or co-doped with Zr, Ce, and Y elements, to generate a cubic BaZr phase in situ on the material surface. 1-A-B Ce A Y B O3, where 0 ≤ A < 1, 0 <B<1。

[0019] Based on the above technical solution, the high-performance proton ceramic fuel cell heterostructure cathode material and its preparation method of the present invention have one or more of the following beneficial effects:

[0020] Compared with existing technologies, this invention provides a high-performance proton ceramic fuel cell heterostructure cathode material with the chemical formula LnBaCo. 2-x Zr x O 5+δ (Ln = La, Pr, Sm, Gd or Eu); where 0.04 ≤ x ≤ 0.5; the cathode material of the present invention, through LnBaCo2O 5+δ The addition of Zr at the B site of the material allows BaZrO3 nanoparticles to desolvate in situ in an oxidizing atmosphere and anchor onto the substrate surface, forming a heterostructure of ion-electron hybrid conductor and proton conductor. This gives the nanocomposite cathode material a triple conductive (oxygen ion-proton-electron) reaction region, as well as good oxygen reduction catalytic activity and excellent chemical and structural stability. It is a method for preparing excellent proton ceramic fuel cell cathode materials and is universally applicable when Ln in the material is La, Pr, Sm, Gd or Eu. Attached Figure Description

[0021] Figure 1 The PrBaCo prepared in Examples 1 to 3 of this invention 2-x Zr x O 5+δ X-ray diffraction pattern of the cathode material;

[0022] Figure 2 The PrBaCo obtained in Examples 1 to 3 of this invention 2-x Zr x O 5+δ Scanning electron microscope image of the cathode material;

[0023] Figure 3 The PrBaCo obtained in Example 2 of this invention 1.92 Zr 0.08 O 5+δ High-resolution transmission electron microscopy (TEM) image and energy dispersive spectroscopy (EDS) spectrum of the cathode material;

[0024] Figure 4 The PrBaCo obtained in Example 2 of this invention 1.92 Zr 0.08 O 5+δ High-angle annular dark-field scanning transmission electron microscope image of the cathode material;

[0025] Figure 5 The PrBaCo obtained in Examples 1 to 3 of this invention 2-x Zr x O 5+δ IV curve of single cell electrochemical test obtained by single-phase cathode application;

[0026] Figure 6The PrBaCo obtained in Example 2 of this invention 1.92 Zr 0.08 O 5+δ Long-term operation diagram of single-cell electrochemical testing obtained by single-phase cathode application;

[0027] Figure 7 The PrBaCo obtained in Examples 1 to 3 of this invention 2-x Zr x O 5+δ X-ray diffraction pattern of cathode material after heat treatment in 3% H2O-air atmosphere. Detailed Implementation

[0028] This invention provides a high-performance heterostructure cathode material for proton ceramic fuel cells and its preparation method. Those skilled in the art can refer to the content of this document and appropriately modify the process parameters to achieve the same result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and fall within the scope of protection of this invention. The method and application of this invention have been described through preferred embodiments. Those skilled in the art can obviously modify or appropriately change and combine the method and application described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0029] According to some embodiments of the present invention, a high-performance proton ceramic fuel cell heterostructure cathode material is provided, in LnBaCo2O 5+δ The system is doped with Zr at the B site, forming a structure with the chemical formula LnBaCo. 2-x Zr x O 5+δ The cathode material is (Ln = La, Pr, Sm, Gd, or Eu); where 0.04 ≤ x ≤ 0.5, and δ is the non-stoichiometry of oxygen; the cathode material includes a substrate and perovskite oxide deposited and anchored on the substrate surface; the substrate is (Ln 1 / (2-x) Ba (1-x) / (2-x) )2Co2O 5+δ The perovskite oxide is BaZrO3.

[0030] In some embodiments of the present invention, 0.04 ≤ x ≤ 0.5, preferably 0.04 ≤ x ≤ 0.12, specifically 0.04, 0.08, or 0.12. Excessive x content will damage the perovskite structure, while insufficient x content will make it difficult to form perovskite oxides through in-situ desolvation.

[0031] In some preferred embodiments of the present invention, the cathode material is PrBaCo. 1.96 Zr 0.04 O 5+δ (abbreviated as PBCZ04), PrBaCo 1.92 Zr0.08 O 5+δ (abbreviated as PBCZ08) or PrBaCo 1.88 Zr 0.12 O 5+δ (Abbreviated as PBCZ12).

[0032] In some preferred embodiments of the present invention, the cathode material can also be LnBaCo2O 5+δ The system is co-doped with Zr and Y elements at the B site, or co-doped with Zr, Ce, and Y elements, to generate a cubic BaZr phase in situ on the substrate surface. 1-A-B Ce A Y B O3, where 0 ≤ A < 1, 0 <B<1。

[0033] The Zr-doped PCFC cathode material provided by this invention possesses oxygen ion, proton, and electron conductance (TCO), enabling simultaneous catalysis and conduction of oxygen ions and protons, as well as electron transport. The B-site doping with Zr significantly stabilizes the material structure and improves its stability compared to the parent material LnBaCo2O. 5+δ This greatly improves the catalytic activity and durability of ORR.

[0034] The PCFC cathode material provided by this invention can be prepared by various methods such as solid-phase synthesis, liquid-phase combustion, and sol-gel method.

[0035] According to some embodiments of the present invention, a method for preparing the above-mentioned proton ceramic fuel cell cathode material is also provided, which involves preparing the cathode material using a liquid-phase combustion method. The preparation method specifically includes the following steps:

[0036] A) Dissolve Ln salt, Ba salt, Co salt and Zr salt in dilute acid, add chelating agent, adjust pH value, stir reaction to obtain the mixture;

[0037] B) The reaction mixture is heated to prepare the precursor;

[0038] C) The precursor is calcined to obtain the proton ceramic fuel cell cathode material.

[0039] The method for preparing proton ceramic fuel cell cathode material provided by this invention firstly involves soluble Ln 3+ Salts, soluble Ba 2+ Salt, soluble Co 3+ Salts and soluble Zr 4+ Dissolve them in dilute acid in sequence, and then add citric acid and ethylenediaminetetraacetic acid as chelating agents.

[0040] In some embodiments of the present invention, Ln salt is preferably Ln(NO3)3·6H2O, Ba salt is preferably Ba(NO3)2, Co salt is preferably Co(NO3)2·6H2O, and Zr salt is preferably Zr(NO3)4·5H2O.

[0041] In some embodiments of the present invention, in addition to dissolving Ln salt, Ba salt, Co salt and Zr salt in dilute acid, Y salt, or Y salt and Ce salt, may also be added to LnBaCo2O 5+δ The system is co-doped with Zr and Y elements at the B site, or co-doped with Zr, Ce, and Y elements, so that a cubic BaZr phase is generated in situ on the material surface. 1-A-B Ce A Y B O3.

[0042] In some embodiments of the present invention, the dilute acid is preferably 10-30 wt% nitric acid; more preferably 15-25 wt% nitric acid.

[0043] In some embodiments of the present invention, adjusting the pH value is preferably done by adding ammonia to adjust the pH value to 7; after adjusting the pH value, a mixed solution is obtained, and then the reaction is stirred; preferably, a magnetic stirrer is used for stirring; the stirring reaction time is preferably 1 to 2 hours; more preferably 1.5 to 2 hours.

[0044] In some embodiments of the present invention, heating the reaction mixture is preferably performed by heating the reaction mixture to auto-ignition after the stirring reaction is complete, and continuing to heat until the combustion reaction is completed to obtain the precursor.

[0045] More specifically, the preferred heating operation is as follows: using a German EGO electric furnace, model 22720-2000W. Heating is performed at a setting of 2.5 to 3 until spontaneous combustion occurs, and then heating continues at a setting of 2.5 to 3 after spontaneous combustion. Preferably, the heating setting is the same before and after spontaneous combustion.

[0046] In some embodiments of the present invention, in the above reaction, the total amount of metal ions in Ln salt, Ba salt, Co salt and Zr salt is in a ratio of 1:1.5:1 to citric acid and ethylenediaminetetraacetic acid.

[0047] In some embodiments of the present invention, the precursor is calcined to obtain a proton ceramic fuel cell cathode material. The calcination temperature is preferably 1000–1200°C; more preferably 1100–1150°C; and the calcination time is preferably 2–3 hours; more preferably 2 hours.

[0048] The proton ceramic fuel cell cathode material provided by this invention has an operating temperature of 500–700°C.

[0049] That is, the cathode material of the present invention exhibits high ORR catalytic activity in the temperature range of 500–700°C. The Zr-doped LnBaCo provided by the present invention... 2-x Zr x O 5+δ The PCFC cathode material exhibits low polarization resistance within the aforementioned temperature range and demonstrates high H2O resistance and durability.

[0050] According to some embodiments of the present invention, a proton ceramic fuel cell is also provided, including an anode, an electrolyte, and a cathode, wherein the cathode adopts the heterostructure cathode material of the proton ceramic fuel cell as described above.

[0051] According to some embodiments of the present invention, a heterostructure cathode material for proton ceramic fuel cells, with the chemical formula PrBaCo, is also provided. 2-x Zr x O 5+δ Where 0.04≤x≤0.5, δ is the non-stoichiometry of oxygen; including the substrate and the perovskite oxide precipitated and anchored on the substrate surface; the substrate is (Ln 1 / (2-x) Ba (1-x) / (2-x) )2Co2O 5+δ Where 0.04 ≤ x ≤ 0.5; the perovskite oxide is BaZrO3. The cathode material of this invention, through doping with high-valence elements at the B site, produces PrBaCo2O... 5+δ The material forms a cubic phase BaZrO3 in situ on its surface. This cathode material not only has triple conductivity (oxygen ion-proton-electron) properties, but also has good oxygen reduction catalytic activity, excellent chemical and structural stability, and strong toughness, making it an excellent proton ceramic fuel cell cathode material.

[0052] The cathode material of this invention is prepared by doping Zr element into PrBaCo2O. 5+δ The Co sites are utilized to improve the structural stability, catalytic activity, structural stability, and durability of the material under water vapor conditions. When the cathode material described in this invention is subjected to long-term treatment in a 3% H2O-air environment, the material's structure remains stable, and no impurity phases are formed.

[0053] The proton ceramic fuel cell cathode material and its preparation method of the present invention will be further described below with reference to specific embodiments and accompanying drawings. It should be noted that the specific embodiments described below are merely illustrative examples, and the scope of protection of the present invention is not limited thereto. All pharmaceuticals or reagents used in the following embodiments are commercially available or prepared in-house using known methods.

[0054] Example 1:

[0055] PrBaCo 1.96Zr 0.04 O 5+δ (abbreviated as PBCZ04) Powder preparation

[0056] Weigh out 8.7002 g of Pr(NO3)3·6H2O (analytical grade), 5.2268 g of Ba(NO3)2 (analytical grade), 11.4084 g of Co(NO3)2·6H2O (analytical grade), and 0.3435 g of Zr(NO3)4·5H2O (analytical grade), and dissolve them in dilute nitric acid solution. Then add 25.2168 g of citric acid (analytical grade) and 23.3792 g of EDTA (analytical grade), and adjust the pH of the solution to 7 by adding ammonia water dropwise to obtain a mixed solution. Stir the mixed solution with a magnetic stirrer for two hours. Heat the solution in a furnace until it spontaneously combusts to obtain the battery cathode material—PrBaCo. 1.96 Zr 0.04 O 5+δ Precursor powder; the precursor powder is calcined at 1100℃ for 2 hours in a high-temperature sintering furnace to obtain the battery cathode material—PrBaCo. 1.96 Zr 0.04 O 5+δ Powder materials.

[0057] Example 2:

[0058] PrBaCo 1.92 Zr 0.08 O 5+δ (abbreviated as PBCZ08) Powder preparation

[0059] Weigh out 8.7002 g of Pr(NO3)3·6H2O (analytical grade), 5.2268 g of Ba(NO3)2 (analytical grade), 11.1756 g of Co(NO3)2·6H2O (analytical grade), and 0.6869 g of Zr(NO3)4·5H2O (analytical grade), and dissolve them in dilute nitric acid solution. Then add 25.2168 g of citric acid (analytical grade) and 23.3792 g of EDTA (analytical grade), and adjust the pH of the solution to 7 by adding ammonia water dropwise to obtain a mixed solution. Stir the mixed solution with a magnetic stirrer for two hours. Heat the solution in a furnace until it spontaneously combusts to obtain the battery cathode material—PrBaCo. 1.92 Zr 0.08 O 5+δ Precursor powder; the precursor powder is calcined at 1100℃ for 2 hours in a high-temperature sintering furnace to obtain the battery cathode material—PrBaCo. 1.92 Zr 0.08 O 5+δ Powder materials.

[0060] Example 3:

[0061] PrBaCo 1.88 Zr0.12 O 5+δ (abbreviated as PBCZ12) Powder preparation

[0062] Weigh out 8.7002 g of Pr(NO3)3·6H2O (analytical grade), 5.2268 g of Ba(NO3)2 (analytical grade), 10.9427 g of Co(NO3)2·6H2O (analytical grade), and 1.0304 g of Zr(NO3)4·5H2O (analytical grade), and dissolve them in dilute nitric acid solution. Then add 25.2168 g of citric acid (analytical grade) and 23.3792 g of EDTA (analytical grade), and adjust the pH of the solution to 7 by adding ammonia water dropwise to obtain a mixed solution. Stir the mixed solution with a magnetic stirrer for two hours. Heat the solution in a furnace until it spontaneously combusts to obtain the battery cathode material—PrBaCo. 1.88 Zr 0.12 O 5+δ Precursor powder; the precursor powder is calcined at 1100℃ for 2 hours in a high-temperature sintering furnace to obtain the battery cathode material—PrBaCo. 1.88 Zr 0.12 O 5+δ Powder materials.

[0063] Performance testing:

[0064] The PrBaCo obtained in Examples 1-3 2-x Zr x O 5+δ Phase structure and morphology analysis of the cathode material were performed, and the results are as follows: Figures 1-4 As shown.

[0065] Figure 1 The PrBaCo obtained in Examples 1-3 of this invention 2-x Zr x O 5+δ X-ray diffraction (XRD) pattern of the cathode material. The XRD indicates that the LnBaCo2O of this invention... 5+δ The system, through Zr doping, specifically formed a structure similar to the cubic BaZrO phase. 3-δ The characteristic peaks match perfectly, which have not been found in some other cathode material systems; except for those with the tetragonal phase PrBaCo2O 5+δ And cubic phase BaZrO 3-δ The characteristic peaks match, and there are no characteristic peaks of other Ba or Co compounds. Based on the overall findings, Zr prepared using the method provided in this invention is a suitable candidate for PrBaCo2O. 5+δ Doping was performed to obtain a Zr-doped composite phase cathode material, PrBaCo. 2- x Zr x O 5+δ .

[0066] Figure 2 The PrBaCo obtained in Examples 1-3 of this invention 2-x Zr x O 5+δ Scanning electron microscope (SEM) image of the cathode material; Figure 3 and Figure 4 The PrBaCo obtained in Example 2 are respectively 2-x Zr x O 5+δ High-resolution transmission electron microscopy (TEM) images, energy-dispersive X-ray spectroscopy (EDS) images, and high-angle annular dark-field transmission electron microscopy (HAADF-STEM) images of the cathode material. It can be seen that the substrate (Pr...) 1 / (2-x) Ba (1-x) / (2-x) )2Co2O 5+δ The perovskite oxide (BaZrO3) exhibits a uniform distribution of elements and a double-layer perovskite structure. The grain size of the precipitated perovskite oxide (BaZrO3) anchored to the substrate surface is <100 nm, and the elements are also uniformly distributed. Furthermore, it can be seen that the precipitation of the BaZrO3 second phase due to Zr doping did not alter the macroscopic morphology of the material. These results demonstrate that this invention successfully yields PrBaCo. 2-x Zr x O 5+δ Cathode materials have opened up new avenues for introducing proton conductivity into proton ceramic fuel cell cathodes.

[0067] Component example:

[0068] Fabrication and PCFC Performance Testing of Asymmetric Single Cells

[0069] BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ (BZCYYb) electrolyte powder, NiO powder, and PMMA pore-forming agent are mixed and ground in a mass ratio of 35:65:10. Then, a polyvinyl alcohol binder solution (polyvinyl alcohol binder solution concentration of 3wt%) is added, accounting for 1wt% of the total amount of ground powder. The mixture is ground in an agate mortar for 2 hours. Then, in a stainless steel mold with a diameter of 13mm, 0.25g / piece of fuel electrode support is pre-pressed at 10MPa. After depressurization, 0.01g / piece of BZCYYb is spread evenly on top of the fuel electrode and pressed into shape at 300MPa. Finally, it is placed in a high-temperature furnace and sintered at 1350℃ for 5 hours to obtain a single cell with fuel electrode support.

[0070] The PrBaCo prepared in Examples 1-3 2-x Zr x O 5+δ(x=0.04,0.08,0.12) powder and terpineol (containing 6% ethyl cellulose) were mixed and ground at a mass ratio of 1:1.5 to prepare an air electrode slurry. The slurry was uniformly coated on the electrolyte side of the above single cell and calcined at 1000℃ for 2 hours to obtain an asymmetric single cell.

[0071] The PrBaCo obtained in Examples 1 to 3 were tested respectively. 2-x Zr x O 5+δ The IV curves of the asymmetric single cell prepared with the cathode material in hydrogen (fuel electrode side) and air (air electrode side) are shown in the following figures. Figure 5 As shown. Figure 5 From top to bottom, the components are PrBaCo2O 5+δ ,PrBaCo 1.96 Zr 0.04 O 5+δ ,PrBaCo 1.92 Zr 0.08 O 5+δ and PrBaCo 1.88 Zr 0.12 O 5+δ IV curves of an asymmetric single cell fabricated from the cathode material at 700℃. Figure 5 It can be known that PrBaCo 1.96 Zr 0.04 O 5+δ The asymmetric single cell prepared from the material has a maximum power density of 934 mW·cm at 700℃. -2 ; by PrBaCo 1.92 Zr 0.08 O 5+δ The asymmetric single cell prepared from the material has a maximum power density of 1430 mW·cm³ at 700 °C. -2 Under the same conditions, PrBaCo2O 5+δ (Maximum power density is 781 mW·cm) -2 The asymmetric single cell prepared from the material is 1.8 times larger than that prepared from PrBaCo. 1.88 Zr 0.12 O 5+δ The asymmetric single cell prepared from the material has a maximum power density of 1047 mW·cm³ at 700 °C. -2 This invention describes the PrBaCo prepared according to the present invention. 1.92 Zr 0.08 O 5+δ The cathode material exhibited excellent electrochemical performance within the test temperature range, and Zr doping effectively improved the catalytic activity and the electrochemical performance of the battery.

[0072] Figure 6 The PrBaCo obtained in Example 2 of this invention2-x Zr x O 5+δ The long-term operating graphs of the asymmetric single cell fabricated with the cathode material in hydrogen (fuel electrode side) and air (air electrode side) show that PrBaCo 1.92 Zr 0.08 O 5+δ The asymmetric single cell prepared from the material operated stably for 140 hours at 600℃ and 0.7V, which is the same as that of PrBaCo2O under the same conditions. 5+δ (Stable operating time is 20h) 7 times that of asymmetric single cells prepared from materials.

[0073] Figure 7 The PrBaCo obtained in Examples 1 to 3 of this invention 2-x Zr x O 5+δ The X-ray diffraction (XRD) pattern of the cathode material after heat treatment at 700℃ in a 3% H2O-air atmosphere shows that PrBaCo 2-x Zr x O 5+δ The cathode material exhibited no other impurity peaks in an atmosphere containing 3% H2O-air, compared to PrBaCo2O. 5+δ The powder exhibits good stability.

[0074] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A heterostructure cathode material for a proton ceramic fuel cell, characterized in that, The cathode material includes a substrate and a perovskite oxide deposited and anchored on the surface of the substrate, wherein the substrate is (Ln 1 / (2-x) Ba (1-x) / (2-x) )2Co2O 5+δ Where Ln = La, Pr, Sm, Gd or Eu, 0.04 ≤ x ≤ 0.12, and δ is the non-stoichiometry of oxygen; The perovskite oxide is BaZrO3; The proton ceramic fuel cell cathode material is prepared by the following method, including: A) Dissolve Ln salt, Ba salt, Co salt and Zr salt in dilute acid, add chelating agent, adjust pH value, stir reaction to obtain reaction mixture; B) Heating the reaction mixture to prepare a precursor; C) The precursor is calcined to obtain the proton ceramic fuel cell cathode material; In step B), heating the reaction mixture specifically includes: heating the reaction mixture to auto-ignition and continuing to heat it until the combustion reaction is complete, wherein the temperature at which the auto-ignition reaction occurs is 120–300°C. In step C), the calcination temperature is 1000-1200℃ and the calcination time is 2-3 hours.

2. The cathode material according to claim 1, characterized in that, In step A), the Ln salt is Ln(NO3)3·6H2O, the Ba salt is Ba(NO3)2, the Co salt is Co(NO3)2·6H2O, and the Zr salt is Zr(NO3)4·5H2O; the chelating agent is citric acid and ethylenediaminetetraacetic acid; and the dilute acid is 10-30 wt% nitric acid. The ratio of the total amount of metal ions in the Ln, Ba, Co, and Zr salts to citric acid and ethylenediaminetetraacetic acid is 1:1.5:

1.

3. The cathode material according to claim 1, characterized in that, In step A), the pH adjustment is achieved by adding ammonia to adjust the pH to 7; the stirring reaction time is 1 to 2 hours.

4. The cathode material according to claim 1, characterized in that, In step A), Y salt, or Y salt and Ce salt, are also added.

5. A proton ceramic fuel cell, comprising an anode, an electrolyte, and a cathode, characterized in that, The cathode is a proton ceramic fuel cell heterostructure cathode material as described in any one of claims 1 to 4.

Images