High-performance proton-solid oxide battery multiphase air electrode material, preparation method and application thereof

Abstract

The invention belongs to the technical field of electrochemical cells, and discloses a high-performance proton-solid oxide cell multi-phase air electrode material, a preparation method and application thereof, the nominal formula of the multi-phase air electrode material is La0. 8Ba0. 1Ag0. 1Co0. 7Ni0. 3O3-delta, and the multi-phase air electrode material has a structure in which a perovskite main phase and an elemental silver and nickel oxide catalytic phase coexist; according to the preparation method of the material, a sol-gel method is adopted for preparation, Ag ions with high electronegativity and high electron conductivity are doped at the site A, silver and nickel oxide are induced to be dissolved out, and a three-phase coexistence structure composed of a metal oxide, a metal elementary substance and a perovskite main phase is formed. The invention also provides an application of the material in preparation of P-SOCs. Compared with a single-phase air electrode, an air electrode prepared from the material shows more excellent proton conduction capability and catalytic activity, so that the air electrode realizes excellent high electrochemical performance in a fuel cell mode and an electrolytic tank mode.

Description

Technical Field

[0001] The present invention relates to the technical field of solid oxide electrochemical cells, and in particular to a high-performance proton-solid oxide cell multiphase air electrode material, a preparation method and application thereof. Background Art

[0002] In order to reduce greenhouse gas emissions, efficient use of clean energy has been one of the key research directions of the scientific and industrial communities in recent decades. Hydrogen energy has the characteristics of environmental friendliness, high energy density and portable transportation, and has received continuous attention. Proton-conducting solid oxide cells (P-SOCs) are highly efficient, pollution-free and do not require precious metal catalysts. They can be used for fuel generation (electrolyzer mode P-SOEC) and power generation (fuel cell mode P-SOFC). Among them, the P-SOFC proton-conducting solid oxide fuel cell (Proton-conducting Solid Oxide Fuel Cell) is a type of solid oxide fuel cell (SOFC). Its characteristics are that it uses proton conductors as electrolytes, operates at lower temperatures, and has higher efficiency and stability. The P-SOEC proton-conducting solid oxide electrolysis cell (Proton-conducting Solid Oxide Electrolysis Cell) is a type of solid oxide electrolysis cell (SOEC), which is used for processes such as electrolysis of water to produce hydrogen, and also uses proton conductors as electrolytes. From the overall perspective of the clean energy development route, P-SOCs are one of the most promising next-generation emerging technologies for low-cost energy storage and conversion.

[0003] In the prior art, proton conductor-solid oxide fuel cells (P-SOFC) are high-temperature fuel cells that can directly convert chemical energy into electrical energy. P-SOCs are mainly composed of porous air electrodes, fuel electrodes, and dense electrolyte layers. Because oxygen-conducting solid oxide cells need to operate at high temperatures (700-850°C), they have challenges of difficult thermal management and impure fuel production. Proton conduction has a lower activation energy at medium temperatures (450-650°C) (protons: 0.3-0.5 eV, oxygen ions: 0.8 eV), so the electrolyte layer uses perovskite structure oxides (BaZr) with high proton conductivity. 0.8 Y 0.2 O 3-δ (BZY), BaZr 0.4 Ce 0.4 Y 0.1 Yb 0.1 O 3–δ(BZCYYb4411)). The hydrogen oxidation / reduction reaction occurring on the fuel electrode involves the conduction of protons and electrons. Therefore, the fuel electrode is composed of NiO (electron conduction) and electrolyte (proton conduction) materials. Oxygen / water vapor is reduced and oxidized on the surface of the porous air electrode to produce oxygen reduction and oxygen evolution reaction (ORR / OER).

[0004] Early air electrodes (mixed oxygen ion-electron conductors (MIECs)) were mainly developed based on oxygen-conducting solid oxide cells, such as Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3-δ (BSCF) and La 0.8 Sr 0.2 MnO 3-δ (LSM), etc. However, as the air electrode of P-SOCs, MIEC has no proton conductivity, and the effective reaction area is limited to the three-phase boundary (air / electrolyte / air electrode). It is crucial to develop triple conductive oxides (TCOs) with proton-electron-oxygen ion conductivity for the air electrode of P-SOCs to expand the effective reaction area to the entire electrode surface. Although some air electrodes with proton conductivity have been developed, such as BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ , PrBa 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5+δ etc. Because protons are introduced in the form of proton defects in the air electrode, the proton conductivity of the air electrode is generally recognized by the proton concentration (proton introduction amount). However, the proton concentration of these air electrodes at 500°C generally does not exceed 0.02 mol, which is only 15% of the proton concentration of the electrolyte material. The difference in proton concentration reflects the difference in proton conductivity. Weak proton conductivity will greatly weaken the effective area of ​​the electrode reaction. The low concentration of proton introduction seriously limits the performance of the air electrode.

[0005] In addition, since the operating temperature of P-SOCs is from high to medium temperature, the reaction energy barrier of OER / ORR on the air electrode will increase with the decrease of temperature, especially more significantly below 550°C, which also limits the electrochemical performance of P-SOCs at medium and low temperatures and is not conducive to its commercialization process. 11, Ag, etc.) have been shown to have catalytic effects on OER / ORR. However, due to various technical difficulties, there are no reports on their application in high-performance air electrode materials. Summary of the invention

[0006] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a high-performance proton-solid oxide battery multiphase air electrode material, a preparation method and its application, and through the simultaneous improvement of material components and processes, develop a multiphase air electrode material with high proton concentration, excellent proton conductivity and efficient OER / ORR catalysis, and further prepare it into high-performance air electrodes and proton-conducting solid oxide batteries P-SOCs, so that it can achieve excellent current density and power density on P-SOCs, so as to overcome the various limitations of existing materials, significantly improve the electrochemical performance of P-SOCs and meet its commercialization needs.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is: A high-performance proton-solid oxide battery multiphase air electrode material, characterized in that it comprises the following steps: its nominal formula is La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ , with La 0.8 Ba 0.1 Ag 0.1-x Co 0.7 Ni 0.3-y O 3-δ A structure in which the perovskite main phase and elemental silver and nickel oxide catalytic phases coexist.

[0008] A method for preparing a high-performance proton-solid oxide battery multiphase air electrode material, characterized in that it is prepared by a sol-gel method, during the preparation process, by 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ The A site is doped with Ag ions with high electronegativity and high electronic conductivity, weakening the bonding between the B site ions and oxygen ions, inducing the dissolution of silver and nickel oxide, and forming a three-phase coexistence structure consisting of metal oxide, metal element and perovskite main phase.

[0009] An application of the high-performance proton-solid oxide battery multiphase air electrode material in the preparation of a proton-solid oxide fuel cell / electrolyzer (P-SOFC / P-SOEC).

[0010] A proton-solid oxide fuel cell / electrolyzer (P-SOFC / P-SOEC) comprises an air electrode prepared from the high-performance proton-solid oxide battery multiphase air electrode material.

[0011] The high-performance proton-solid oxide battery multiphase air electrode material, preparation method and application thereof provided by the present invention have at least the following beneficial effects: 1. The present invention develops a multiphase air electrode material with high proton concentration, excellent proton conductivity and efficient OER / ORR catalysis by simultaneously improving material components and processes, and further prepares it into high-performance air electrodes and P-SOCs, so that it can achieve excellent current density and power density on P-SOCs, so as to overcome the various limitations of existing materials, significantly improve the electrochemical performance of P-SOCs and meet its commercialization needs.

[0012] 2. In order to overcome the above-mentioned shortcomings and deficiencies of the existing technology, the present invention aims at the preparation and application of air electrodes with coexistence of proton / electron / oxygen ion triple conduction phase and OER / ORR reaction catalytic phase, so as to achieve excellent current density and power density on P-SOCs. The present invention provides an air electrode with excellent performance, which has a perovskite main phase and a nickel oxide / silver catalytic phase. The three-phase air electrode has a smaller area specific resistance, excellent proton conduction capacity, and a larger effective reaction area. This enables the three-phase air electrode to achieve excellent electrochemical performance in P-SOCs at medium and low temperature working temperatures.

[0013] 3. The present invention focuses on the La 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ The A-site of the electrode is doped with Ag ions with high electronegativity and high electronic conductivity to weaken the bonding between the B-site ions and the oxygen ions, thereby inducing the dissolution of silver and nickel oxide to form a three-phase coexistence structure consisting of metal oxide, metal element and perovskite main phase. The nominal formula of the air electrode is La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ The three-phase air electrode exhibits superior proton conductivity and catalytic activity compared to the single-phase air electrode, enabling it to achieve excellent electrochemical performance in both fuel cell and electrolyzer modes.

[0014] 4. The present invention is a single-phase perovskite La 0.8 Ba 0.2 Co 0.7 Ni 0.3 O3-δ The air electrode prepared by the sol-gel method has a nominal formula of La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ , a structure containing three phases of perovskite, silver and nickel oxide coexisting is synthesized in one step, and the preparation process is simple. The air electrode material of the present invention is applied to the BZCYYb4411 symmetrical battery and exhibits a low area specific resistance (ASR) and excellent electrode reaction activity.

[0015] 5. The air electrode material prepared by the present invention is applied to P-SOCs, and it exhibits excellent electrochemical performance in both fuel cell mode and electrolytic cell mode. The maximum power density at 600, 550, 500, and 450°C is 1.27, 0.78, 0.66, and 0.52 W cm, respectively. -2 , the current density is 2.5, 1.63, 1.06, 0.62 A cm at 650, 600, 550, 500 °C and 1.3 V. -2 ; Therefore, the P-SOCs provided by the present invention have good electrochemical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ and La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ XRD pattern of Figure 2 The air electrode material La of the present invention 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ TEM image and EDSmapping image (including elements La, Ba, Ag, Co, Ni, O); Figure 3 The air electrode material La of the present invention 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ and La0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ XPS patterns, including (a) Ag 3d, (b) Ba 3d+Co 2p, (c) La 3d+Ni2p, (d) O 1s; Figure 4 The air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ and La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ EPR curve diagram; Figure 5 Air electrode material prepared in the embodiment of the present invention (a) La 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ and(b)La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ Thermogravimetric curve of the test; the test conditions are dry air and humidified air containing 3% volume fraction of water vapor at 50-800℃ to detect mass changes; Figure 6 The air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ and La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ The proton concentration curve is obtained by calculating the mass difference between dry air and wet air at the same temperature; Figure 7 XRD comparison diagram of the electrolyte material and the fuel electrode material prepared in the embodiment of the present invention; Figure 8 Air electrode material prepared in the embodiment of the present invention (a) La 0.8 Ba 0.1Ag 0.1 Co 0.7 Ni 0.3 O 3-δ and(b)La 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ The electrochemical impedance spectroscopy (EIS) curves of the symmetrical battery (air electrode-electrolyte-air electrode) prepared with BZCYYb4411 as the electrolyte were measured in the range of 500-650°C in humidified air containing 3% water vapor by volume. Fig. 9 The air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ and La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ The activation energy curve is calculated from the area specific resistance of a symmetrical battery (air electrode-electrolyte-air electrode) prepared with BZCYYb4411 as the electrolyte and tested in the range of 500-650℃; Fig.10 The air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ Applied in P-SOCs (air electrode-electrolyte-fuel electrode), where the electrolyte material is BZCYYb4411 and the fuel electrode material is NiO-BZCYYb4411. IV curve tested in the electrolytic cell mode (humidified hydrogen containing 3% volume fraction of water vapor is passed into the fuel electrode side, and humidified air containing 3% volume fraction of water vapor is passed into the air electrode side) in the temperature range of 450-650℃; Fig.11 The air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δApplied in P-SOCs (air electrode-electrolyte-fuel electrode), where the electrolyte material is BZCYYb4411 and the fuel electrode material is NiO-BZCYYb4411. IVP curve tested in the fuel cell mode (humidified hydrogen containing 3% volume fraction of water vapor is passed into the fuel electrode side, and humidified air containing 3% volume fraction of water vapor is passed into the air electrode side) in the temperature range of 400-600℃; Fig.12 The air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ Applied in P-SOCs (air electrode-electrolyte-fuel electrode), where the electrolyte material is BZCYYb4411 and the fuel electrode material is NiO-BZCYYb4411; EIS impedance spectrum in the temperature range of 450-650 (humidified hydrogen containing 3% volume fraction of water vapor is passed into the fuel electrode side, and humidified air containing 3% volume fraction of water vapor is passed into the air electrode side); Fig.13 The air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ XRD pattern of calcination at 600 °C for 100 h in humidified air with 3% volume fraction of water vapor; Fig.14 The air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ Applied in P-SOCs (air electrode-electrolyte-fuel electrode), where the electrolyte material is BZCYYb4411 and the fuel electrode material is NiO-BZCYYb4411; cross-sectional SEM image of P-SOCs after testing. DETAILED DESCRIPTION

[0017] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0018] Unless otherwise specified, the following embodiments of the present invention use equipment, instruments and raw materials that are commercially available.

[0019] Example 1 See attached Figure 1-Figure 4The high-performance proton-solid oxide battery multiphase air electrode material provided in the embodiment of the present invention (specifically, a three-phase air electrode material for proton-solid oxide battery P-SOCs) has a nominal formula (molecular formula) of La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ The finished product is a powder, numbered LBACN81173, for preparing proton-solid oxide batteries P-SOCs, which has La 0.8 Ba 0.1 Ag 0.1-x Co 0.7 Ni 0.3-y O 3-δ The structure of the coexistence of the main phase of perovskite and the catalyst phase of elemental silver and nickel oxide. For comparison, this embodiment also provides a single-phase perovskite powder material without silver, with a nominal formula of La 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ The powder is numbered LBCN8273.

[0020] The physical and chemical properties of LBACN81173 and LBCN8273 powder materials were tested respectively. The test results are shown in the attached Figure 1-Figure 4 .

[0021] 1. XRD characterization results observe Figure 1 The XRD characterization results show that La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ (LBACN81173) and La 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ (LBCN8273) powder X-ray diffraction (XRD) pattern; By consulting the PDF card and comparing the XRD curves of the two air electrodes, LBCN8273 is a perovskite single-phase air electrode material, and LBACN81173 is observed to have La 0.8 Ba 0.1 Ag 0.1-x Co 0.7 Ni 0.3-y O 3-δIn addition to the perovskite structure, there are also nickel oxide and silver phases, indicating that an air electrode material with three phases of perovskite, nickel oxide and silver coexisting has been prepared. Therefore, it is shown that a three-phase air electrode material LBACN81173 can be synthesized by doping highly electronegative Ag at the A site and a simple sol-gel method.

[0022] 2. TEM characterization results Figure 2 This is the transmission scanning electron microscope (TEM) of the LBACN81173 air electrode, where the lattice fringes and EDS element distribution of the perovskite phase, the EDS element distribution of Ag, and the lattice fringes of nickel oxide can be observed. This phenomenon confirms that the LBACN81173 air electrode is a three-phase coexistence structure.

[0023] 3. XPS characterization results See also Figure 3 (a) By observing the XPS graph of the air electrode Ag of LBACN81173, it is shown that Ag exists in the air electrode material in the form of elemental silver and silver ions; Figure 3 (b) Figure 3 As can be seen in (c), the XPS peaks of La 3d-Ni 2p and Ba 3d-Co2p of LBACN81173 shift to lower binding energy compared with LBCN8273, which confirms that the strength of the metal-oxygen bond in the air electrode is weakened after Ag doping with high electronegativity, which contributes to the formation of oxygen vacancies; Figure 3 (d) shows the XPS peaks of oxygen of LBACN81173 and LBCN8273, and LBACN81173 exhibits a higher oxygen vacancy concentration.

[0024] 4. EPR characterization results like Figure 4 As shown, the LBACN81173 and LBCN8273 air electrodes were subjected to EPR tests respectively, and LBACN81173 showed a higher relative intensity, which confirmed that LBACN81173 had a higher oxygen vacancy concentration than LBCN8273, and this result was consistent with XPS.

[0025] Example 2 Based on Example 1, the present invention provides a high-performance proton-solid oxide battery multiphase air electrode material (specifically a three-phase air electrode material, whose nominal formula (molecular formula) is La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ The preparation method specifically comprises the following steps:

[0026] As a comparison, this embodiment also provides La 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ The preparation method of (LBCN8273) powder specifically comprises the following steps: 1) According to La 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ According to the stoichiometric ratio, 2.002g lanthanum nitrate, 0.302g barium nitrate, 1.176g cobalt nitrate, and 0.5139g nickel nitrate were weighed, deionized water was added, and heated to 50 degrees in a beaker and stirred until completely dissolved.

[0027] 2) According to the molar ratio of total metal ions to citric acid monohydrate of 1:1, weigh 2.439g of citric acid monohydrate and add it into a beaker.

[0028] 3) The mixed solution is heated at a constant temperature of 90 degrees and stirred continuously at a speed of 300 r / min until the water is completely evaporated to form a gel-like substance.

[0029] 4) Place the gel-like substance in a muffle furnace and heat it to 500 degrees at 5 degrees / minute and keep it for one hour to volatilize the residual organic matter to obtain an air electrode precursor.

[0030] 5) Grind the obtained precursor material thoroughly to form powder.

[0031] 6) The air electrode precursor powder is calcined in a muffle furnace at 1000 degrees for 8 hours to obtain an air electrode material having a perovskite single phase. The LBCN8273 prepared in this example has a perovskite single phase structure.

[0032] See attached Figure 1-Figure 4 The physical and chemical properties of the LBACN81173 and LBCN8273 powder materials prepared in this embodiment were tested, and the test results were the same as those in Example 1.

[0033] Example 3 This embodiment is based on the embodiment 1 and the embodiment 2, and further provides a method of using La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ The prepared air electrode is further prepared into a symmetrical battery (air electrode-electrolyte-air electrode) using BZCYYb4411 as an electrolyte and a preparation method thereof, which specifically comprises the following steps: 1) According to the stoichiometric ratio of BZCYYb4411, weigh 5.051 g of barium carbonate, 1.249 g of zirconium oxide, 1.746 g of cerium oxide, 0.286 g of yttrium trioxide, and 0.499 g of ytterbium trioxide, and add 100 ml of ethanol, put it in a ball mill at 300 r / min for 10 h, and then take it out and dry it to obtain a mixed powder.

[0034] 2) The dried mixed powder was calcined at 1100°C for 10 h in a muffle furnace, and the calcined powder was ball-milled at 300 r / min for 10 h in a ball mill, and then taken out and dried. The above steps were repeated to obtain BZCYYb4411 electrolyte material powder.

[0035] 3) BZCYYb4411 powder was placed in a 13 mm tabletting mold to produce an electrolyte sheet with a height of about 1 mm and a diameter of about 13 mm.

[0036] 4) The green embryo is placed in a muffle furnace and calcined at 1450°C for 8 hours to form an electrolyte sheet.

[0037] 5) The air electrode powder and pinene alcohol were mixed in a mass ratio of 1:1.5 and placed in a ball mill. The ball milling condition was 300 r / min and rotated for 5 h to obtain air electrode slurry.

[0038] 6) The air electrode slurry is evenly coated on both sides of the electrolyte sheet by screen printing to prepare a symmetrical battery (air electrode-electrolyte-air electrode).

[0039] The symmetrical battery prepared in this embodiment can achieve area specific resistances of 0.13, 0.33, 0.81, and 1.69 Ω cm at 650, 600, 550, and 500°C. 2 .

[0040] Example 4

[0041] This embodiment is based on the embodiment 1-3, using La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ The prepared air electrode and the further prepared full battery (air electrode-electrolyte-fuel electrode) are prepared by the following steps: 1) 3g BZCYYb4411 powder, 2g nickel oxide, and 1g starch were placed in a ball mill at a mass ratio of 6:4:1, and 100ml ethanol was added. The ball milling condition was 300r / min rotation for 10h, and then dried on a heating table at 150℃ until the ethanol was completely volatilized to obtain a uniformly mixed fuel electrode powder.

[0042] 2) Weigh 0.7 g of fuel electrode powder and place it in a 13 mm tablet pressing mold. Keep it at a pressure of 20 MPa for one minute to obtain a support body embryo. The diameter of the disc is about 13 mm and the height is about 1 mm.

[0043] 3) BZCYYb4411 powder, dispersant and surfactant were placed in a ball mill at a mass ratio of 20:4:1. The ball milling condition was 300 r / min and rotation for 10 h to obtain electrolyte slurry.

[0044] 4) Use a pipette to drop the electrolyte slurry onto the surface of the support, and then spin it on a spin coater to form an electrolyte layer. The spin coating conditions are 3000r / min for 15 seconds and drying on a heating table at 150°C. Then place it in a muffle furnace and calcine it at 350°C for 1 hour to volatilize organic matter, and then heat it to 1450°C and calcine it for 8 hours to obtain a half-cell.

[0045] 5) The air electrode powder and pinene alcohol were mixed in a mass ratio of 1:1.5 and placed in a ball mill. The ball milling condition was 300 r / min and rotated for 5 h to obtain air electrode slurry.

[0046] 6) The air electrode slurry is evenly coated on the electrolyte layer side by screen printing to prepare a full cell (air electrode-electrolyte-fuel electrode).

[0047] 7) The electrolyte layer thickness of the full battery prepared by this method is about 11-13 microns, and the air electrode thickness is about 25 microns.

[0048] The maximum power density of the full battery prepared in this example at 600, 550, 500, and 450°C is 1.27, 0.78, 0.66, and 0.52 W cm -2 At 650, 600, 550, 500, and 450°C, the current densities of P-SOCs at 1.3 V are 2.5, 1.63, 1.06, 0.62, and 0.17 A cm -2 .

[0049] The powder materials and full batteries prepared in the above-mentioned Examples 1-4 were subjected to performance tests, and the characterization results obtained were as follows: 1. XRD characterization exist Figure 1 The La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ (LBACN81173) and La 0.8 Ba 0.2 Co0.7 Ni 0.3 O 3-δ X-ray diffraction (XRD) diagram of (LBCN8273) powder. By consulting the PDF card and comparing the XRD curves of the two air electrodes, LBCN8273 is a perovskite single-phase air electrode material, and LBACN81173 is observed to have La 0.8 Ba 0.1 Ag 0.1-x Co 0.7 Ni 0.3-y O 3-δ In addition to the perovskite structure, there are also nickel oxide and silver phases, indicating that the preparation of La 0.8 Ba 0.1 Ag 0.1-x Co 0.7 Ni 0.3-y O 3-δ The three-phase coexistence of nickel oxide and silver in the air electrode material shows that a three-phase air electrode material LBACN81173 can be synthesized by doping highly electronegative Ag at the A site and a simple sol-gel method.

[0050] 2. TEM characterization like Figure 2 Transmission scanning electron microscopy (TEM) of the LBACN81173 air electrode shows that La 0.8 Ba 0.1 Ag 0.1-x Co 0.7 Ni 0.3-y O 3-δ Lattice fringes and EDS element distribution of perovskite phase, EDS element distribution of Ag and lattice fringes of nickel oxide. This phenomenon confirms that the LBACN81173 air electrode is a three-phase coexistence structure. The particle size of the prepared air electrode particles is about 200nm.

[0051] 3.XPS characterization like Figure 3 As shown in (a), the XPS graph of the Ag in the air electrode of LBACN81173 shows that Ag exists in the air electrode material in the form of single silver and silver ions. Figure 3 As can be seen in (b), the XPS peaks of La 3d-Ni 2p and Ba3d-Co2p of LBACN81173 shift to lower binding energy compared with LBCN8273, which confirms that the strength of the metal-oxygen bond in the air electrode is weakened after the highly electronegative Ag doping, which contributes to the formation of oxygen vacancies. Figure 3 As shown in (c), the XPS peaks of oxygen of LBACN81173 and LBCN8273, LBACN81173 exhibits a higher oxygen vacancy concentration.

[0052] 4. EPR Characterization like Figure 4 As shown in Figure 1, the LBACN81173 and LBCN8273 air electrodes were subjected to EPR testing. LBACN81173 exhibited a higher relative intensity, which confirmed that LBACN81173 had a higher oxygen vacancy concentration than LBCN8273, which was consistent with the XPS result.

[0053] 5. Thermogravimetric Characterization Figure 5 The relationship between temperature and mass of LBACN81173 and LBCN8273 air electrodes in dry air and 3% volume fraction water air at temperatures of 100-800°C. Figure 5 (a) is the air electrode material La prepared in the embodiment of the present invention 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ Thermogravimetric curve of Figure 5 (b) is La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ Thermogravimetric curve of the test; the test conditions are dry air and humidified air containing 3% volume fraction of water vapor at 50-800℃ to detect mass changes; Figure 6 According to the hydration reaction equation ( ), the amount of protons introduced into the air electrode can be obtained by calculating the mass difference between dry and wet atmospheres at the same temperature, and the relationship between the proton concentration and temperature of the air electrodes of LBACN81173 and LBCN8273 is obtained. LBACN81173 exhibits a higher proton concentration than LBCN8273. In addition, the proton concentration of LBACN81173 is higher than that of most mainstream air electrodes for P-SOCs, and has excellent proton conductivity.

[0054] 6. Electrochemical Impedance Characterization Figure 7 This is the XRD pattern of BZCYYb4411, showing a single-phase perovskite structure without other impurities. Figure 8 a and 8b are the impedance spectra of the symmetrical battery test of LBACN81173 and LBCN8273 applied to BZCYYb4411. The test temperature is 650-500℃, and the atmosphere is air containing 3% volume fraction of water. It can be seen from the figure that at 650, 600, 550, 500℃, the area specific resistance of LBACN81173 is 0.13, 0.33, 0.81, 1.69 Ω cm2 The area specific resistance of LBCN8273 is 0.20, 0.55, 2.50, and 5.00 Ω cm 2 The area specific resistance of LBACN81173 is significantly smaller than that of LBCN8273. In addition, the area specific resistance of LBACN81173 is lower than that of most mainstream air electrodes for P-SOCs, and has certain commercial prospects.

[0055] 7. Activation energy test Fig. 9 The area specific resistance of LBACN81173 and LBCN8273 applied to BZCYYb4411 electrolyte sheet is shown, and the activation energy is calculated. The LBACN81173 three-phase air electrode has a lower activation energy under the same test conditions. This is mainly attributed to the catalytic effect of metal element silver and metal oxide nickel oxide on the electrode reaction occurring on the air electrode.

[0056] 8. Output power characterization Figure 7 The XRD patterns of electrolyte BZCYYb4411 and fuel electrode Ni-BZCYYb4411 show a single-phase perovskite structure, while Ni-BZCYYb4411 shows the XRD peaks of BZCYYb4411 perovskite structure and Ni, without other impurities. The LBACN81173 air electrode is applied to the P-SOCs half-cell to form a full cell (LBACN81173-BZCYYb-NiO-BZCYYb). Fig.11 The IV curve and IP curve in the temperature range of 600-400℃. It can be seen from the figure that at 600, 550, 500, and 450℃, the maximum power density of P-SOCs is 1.27, 0.78, 0.66, and 0.52 W cm -2 The maximum power density of LBACN81173 is higher than that of most mainstream air electrodes for P-SOCs, and it has certain commercial prospects in the field of fuel cells.

[0057] 9. Characterization of electrolytic performance The LBACN81173 air electrode was prepared as a P-SOCs half-cell and then formed into a full cell (LBACN81173-BZCYYb-NiO-BZCYYb). Fig.10 This is the IV curve in the temperature range of 650-450℃. From the figure, it can be seen that at 650, 600, 550, 500, and 450℃, the current density of P-SOCs at 1.3V is 2.5, 1.63, 1.06, 0.62, and 0.17 Acm-2 The current density of LBACN81173 at 1.3V is higher than that of most mainstream air electrodes for P-SOCs, and has certain commercial prospects in the field of electrolytic cells.

[0058] 10. Impedance Characterization The LBACN81173 air electrode was prepared as a P-SOCs half-cell and then formed into a full cell (LBACN81173-BZCYYb-NiO-BZCYYb). Fig.12 This is the impedance spectrum in the temperature range of 650-450℃. It can be seen from the figure that at 650, 600, 550, 500, and 450℃, the polarization resistance of P-SOCs is 0.025, 0.062, 0.118, 0.236, and 0.709 Ωcm respectively. 2 .

[0059] 11. Stability Characterization Fig.13 This is the XRD pattern of the sample treated at 600℃ for 100h in air with 3% water volume fraction. Fig.13 It can be seen that no other impurities are produced after the stability test, indicating that the LBACN81173 three-phase air electrode has good stability.

[0060] 12. Battery microstructure characterization Fig.14 The P-SOCs after the test were subjected to scanning electron microscopy for microstructural characterization. From the figure, it can be seen that the P-SOCs are composed of porous air electrodes and fuel electrodes, and a dense electrolyte layer. Both the fuel electrode and the air electrode are in close contact with the electrolyte layer.

[0061] The high-performance proton-solid oxide battery multiphase air electrode material, preparation method and application thereof provided in the above embodiments, the nominal formula of the multiphase air electrode material is La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ , with La 0.8 Ba 0.1 Ag 0.1-x Co 0.7 Ni 0.3-y O 3-δ The structure of the coexistence of the main phase of perovskite and the catalyst phase of elemental silver and nickel oxide; the preparation method of the material is to adopt the sol-gel method, in the preparation process, by 0.8 Ba 0.2 Co 0.7 Ni 0.3 O3-δ The A-site of the material is doped with Ag ions with high electronegativity and high electronic conductivity, weakening the bonding between the B-site ions and the oxygen ions, inducing the dissolution of silver and nickel oxide, and forming a three-phase coexistence structure consisting of metal oxide, metal element and perovskite main phase. The present invention also provides the application of the material in the preparation of P-SOCs. The air electrode prepared using the material exhibits better proton conductivity and catalytic activity than the single-phase air electrode, enabling it to achieve excellent high electrochemical performance in both fuel cell and electrolytic cell modes.

[0062] The high-performance proton-solid oxide battery multiphase air electrode materials, preparation methods and applications provided in the above-mentioned embodiments of the present invention focus on developing multiphase air electrode materials with high proton concentration, excellent proton conductivity and efficient OER / ORR catalysis through the simultaneous improvement of material components and processes, and further preparing them into high-performance air electrodes and proton-conducting solid oxide batteries P-SOCs, so that they can achieve excellent current density and power density on P-SOCs, so as to overcome the various limitations of existing materials, significantly improve the electrochemical performance of P-SOCs and meet their commercialization needs.

[0063] It should be noted that the above embodiments describe only a part of the embodiments of the present invention, rather than all the embodiments. In other embodiments, within the scope of the present invention, the technical solutions obtained by selecting other components, proportions and process parameters can also achieve the technical effects recorded in the present invention, so they are not listed one by one.

[0064] The specific embodiments described above are only an introduction to the optimization method of the present invention, and are not intended to limit the scope of the present invention. It should be noted that, without departing from the spirit of the present invention, those skilled in the art may make appropriate adjustments or modifications to the technical solution of the present invention, which shall fall within the scope of protection determined by the claims of the present invention.

Claims

1. A high-performance proton-solid oxide battery multiphase air electrode material, characterized in that: It includes the following steps: Its nominal formula is La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ , with La 0.8 Ba 0.1 Ag 0.1-x Co 0.7 Ni 0.3-y O 3-δ A structure in which the main phase of perovskite and the catalytic phases of elemental silver and nickel oxide coexist.

2. A method for preparing a high-performance proton-solid oxide battery multiphase air electrode material, characterized in that: It is prepared by the sol-gel method. 0.8 Ba 0.2 Co 0.7 Ni 0.3 O 3-δ The A site is doped with Ag ions with high electronegativity and high electronic conductivity, weakening the bonding between the B site ions and oxygen ions, inducing the dissolution of silver and nickel oxide, and forming a three-phase coexistence structure consisting of metal oxide, metal element and perovskite main phase.

3. The method for preparing a high-performance proton-solid oxide battery multiphase air electrode material according to claim 2, characterized in that: It includes the following steps: S1: According to the stoichiometric ratio of 8:1:1:7:3, lanthanum nitrate, barium nitrate, silver nitrate, cobalt nitrate and nickel nitrate are weighed respectively, added into a container, stirred with an appropriate amount of deionized water, and heated to dissolve; S2: After all components are dissolved, add citric acid monohydrate, and the molar ratio of citric acid monohydrate to metal ions is (1~1.5:):(1~1.5); S3: then, under heating and stirring conditions, the water is evaporated to form a gel material; S4: placing the gel material in a muffle furnace for calcining once to form a precursor of the air electrode material; S5: Grind the precursor into powder, and then place it in a muffle furnace for secondary calcination to obtain a nominal formula of La 0.8 Ba 0.1 Ag 0.1 Co 0.7 Ni 0.3 O 3-δ High-performance multiphase air electrode materials for proton-solid oxide batteries.

4. The method for preparing a high-performance proton-solid oxide battery multiphase air electrode material according to claim 3, characterized in that: The step S3 is to heat and stir at 80-90° C. for 3-5 hours until the water is completely evaporated to form a gel material.

5. The method for preparing a high-performance proton-solid oxide battery multiphase air electrode material according to claim 3, characterized in that: The primary calcination in step S4 is to treat the gel material in a muffle furnace at a temperature of 350-500° C. and a heating rate of 5-10° C. / min for 1-2 hours to form a solid precursor of the air electrode material.

6. The method for preparing a high-performance proton-solid oxide battery multiphase air electrode material according to claim 3, characterized in that: The secondary calcination in step S5 is to treat the ground precursor powder in a muffle furnace at a temperature of 900-1100° C. and a heating rate of 5-10° C. / min for 5-8 hours to obtain a high-performance proton-solid oxide battery multiphase air electrode material.

7. Use of the high-performance proton-solid oxide battery multiphase air electrode material according to claim 1 in the preparation of a proton-solid oxide fuel cell / electrolyzer.

8. The use according to claim 7, characterized in that: The high-performance proton-solid oxide battery multiphase air electrode material is prepared as an air electrode of P-SOCs, comprising the following steps: A1: preparing a high-performance proton-solid oxide battery multiphase air electrode material into a slurry, specifically, mixing the multiphase air electrode material with pineneol in a mass ratio of (1-1.5): (1-1.5) and ball milling; A2: Screen printing is used on the electrolyte layer side of the half-cell, and after drying in an oven and volatilizing the organic matter, the P-SOCs air electrode is obtained.

9. The use according to claim 8, characterized in that: The air electrode prepared from the high-performance proton-solid oxide battery multiphase air electrode material is further prepared into P-SOCs, which are prepared from electrolyte, fuel electrode and starch (pore forming), wherein the electrolyte is a proton conductor BaZr 0.4 Ce 0.4 Y 0.1 Yb 0.1 O 3-δ (BZCYYb4411), the fuel electrode is a composite material prepared by mixing nickel oxide, BZCYYb4411 and starch, the mass ratio of nickel oxide, BZCYYb4411 and starch is 6:4:1, and includes the following steps: B1: Pressing the fuel electrode material into a sheet to obtain a fuel electrode support; B2: preparing electrolyte material and air electrode material into slurry respectively; B3: Spin coating the electrolyte slurry on the fuel electrode support substrate to form a thin film and dry it; B4: heat treating the obtained thin sheet at low temperature to volatilize organic matter, and then sintering at high temperature to obtain a half-cell of electrolyte layer / fuel electrode support; The electrolyte slurry is obtained by ball milling BZCYYb4411 powder, dispersant and surfactant, wherein the mass ratio of BZCYYb4411: dispersant: surfactant is (80-100): (10-20): (2-5); The conditions for the low temperature volatile organic matter are heat treatment at 350-450°C for 1-2h; The high temperature sintering condition is 1400-1500° C. for 6-9 hours.

10. A proton-solid oxide fuel cell / electrolyzer, characterized in that: It comprises an air electrode prepared from the high-performance proton-solid oxide battery multiphase air electrode material according to claim 1.

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