Method and device for testing proton migration rate based on solid oxide

Abstract

The invention relates to a test method and device based on a solid oxide proton migration rate, and belongs to the technical field of solid oxide fuel cells. By regulating and controlling the water pressure in the atmosphere where the material is located and monitoring the change rule of the conductivity along with time in the process in real time, bulk-phase proton migration kinetic parameters are obtained, and the bulk-phase proton migration rate of the triple conductive material is quantitatively researched from the perspective of reaction kinetics. And direct quantitative evaluation of the proton migration rate is realized. By utilizing the testing method, the bulk phase proton migration rate of various triple conductive materials can be tested.

Description

Technical Field

[0001] The present invention relates to a test method and device for the proton migration rate of solid oxides, belonging to the technical field of solid oxide fuel cells. Background Art

[0002] Solid Oxide Fuel Cells (SOFCs) are all-solid-state ceramic energy conversion devices that directly convert chemical energy into electrical energy. They have the advantages of being clean and safe, having strong fuel adaptability, and high energy conversion efficiency, and have broad application prospects in fields such as small household combined heat and power systems, distributed power stations, auxiliary power sources for automobiles, ships, and military applications. As an important means to solve energy and environmental problems, it has received extensive attention.

[0003] Solid oxide materials with proton conductivity can operate at medium and low temperatures due to their low proton barriers, thus avoiding many problems caused by high temperatures. However, in solid oxides with proton conductivity, quantitatively evaluating the proton migration rate is a key issue for understanding and optimizing material properties. A high proton migration rate means lower electrolyte internal resistance, which can improve the energy conversion efficiency of the system; in addition, quantitative research on the proton migration rate also helps to reduce local overheating and stress concentration, and slow down material aging or performance degradation.

[0004] Currently, the evaluation of the proton migration rate mainly relies on the thermogravimetric relaxation method. Although this method can provide qualitative evaluation, quantitative characterization needs to be achieved through theoretical calculations, which to a certain extent limits the convenience and accuracy of its practical application. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a test method and device for the proton migration rate of solid oxides. The present invention changes the water vapor pressure in the atmosphere where the material is located, and records the change law of conductivity over time during the change of water vapor pressure to achieve quantitative evaluation of the proton migration rate. This method avoids the complex theoretical calculations in traditional methods, making the evaluation process more intuitive, accurate, and easy to operate.

[0006] To achieve the above purpose, the technical solution of the present invention is as follows.

[0007] A test method for the proton migration rate of solid oxides, the method steps include:

[0008] (1) Mix the solid oxide with a binder, grind, press, and calcine to obtain a rectangular parallelepiped sample strip with a relative density > 95%.

[0009] (2) One end of a plurality of silver wires is uniformly wound and fixed on a sample strip along the length direction, and then the sample strip is placed in a tube furnace and connected to a conductivity meter, while ensuring insulation isolation between the silver wires; sintering at 750-800°C for 30-120 minutes and then cooling;

[0010] (3) Under a protective gas atmosphere, after the temperature in the tube furnace is stabilized at a set temperature, water vapor is introduced into the tube furnace, and the conductivity of the sample strips under different water partial pressures is tested by a conductivity meter;

[0011] (4) Based on the conductivity results, combined with Fick's second diffusion law and the charge balance equation, a diffusion equation for the change of conductivity with time containing the proton bulk diffusion coefficient was established, and the proton migration rate of the solid oxide was obtained by fitting.

[0012] Furthermore, in step (1), the binder is polyvinyl alcohol (PVA), and the addition amount is 5% to 10% of the total mass of the mixed system; pressing is performed at a pressure of 15 to 20 MPa for 5 to 10 minutes, and then calcined in a muffle furnace at 1100 to 1200° C. for 2 to 3 hours.

[0013] Furthermore, in step (2), the silver wires are fixed to the sample strip by silver paste; and / or, the silver wires are placed in a ceramic tube and fixed in a tube furnace to ensure insulation isolation between the silver wires.

[0014] Furthermore, in step (3), the protective gas is nitrogen or an inert gas (a gas element corresponding to all Group 0 elements on the periodic table).

[0015] Furthermore, in step (3), the temperature is set at 550-750°C.

[0016] Furthermore, in step (3), based on the total volume of the protective gas and water vapor in the tubular furnace being 100%, the volume fraction of the water vapor is 3% to 10%.

[0017] Furthermore, in step (4), the three-dimensional dimensions of the sample strip are assumed to be 2a×2b2c, and the conductivity reading detected in real time is combined with Fick's second diffusion law:

[0018] Among them, C i is the concentration distribution of ion i, D i，chem is the bulk diffusion coefficient of ion i, i represents oxygen ion when O, and represents proton when i represents H;

[0019] At t = 0, the sample is in equilibrium and the concentrations of all ions are known constants, so the initial conditions are: C i (x, o) = C i，0 (Formula 2);

[0020] Since both oxygen ions and protons diffuse from the sample surface towards the center of the cuboid sample, the concentration distribution is symmetric. At any given moment, the rate of change of concentration at the center of the sample is 0. Therefore, in the x-axis direction, we have:

[0021]

[0022] On the surface of the sample strip, the concentrations of oxygen ions and protons both originate from the transformation of water molecules on the sample surface. Assuming that within the given range of oxygen partial pressure and test water vapor pressure changes, the conversion coefficient of water molecules on the sample is constant. Then, combining with Fick's first law of diffusion, an equation is established with the ion transport flux. In the x-axis direction, there are boundary conditions:

[0023] where, is the conversion coefficient of water molecules on the sample surface, C i，∞ is the concentration distribution of ion i in the equilibrium state;

[0024] Successively replace x in Formulas 1 to 4 with y and z, and a with b and c to obtain the corresponding diffusion equations, initial conditions, and boundary conditions in the y and z axis directions, thereby obtaining the diffusion equations of oxygen ions and protons in three-dimensional space;

[0025] According to the charge balance equation in the oxide, we have: c h = ξ - c H - 2c O (Formula 5);

[0026] where, ξ is the total charge of the local charges at all cation positions in the sample strip material, c h is the hole concentration, c H and c O are the average concentrations of protons and oxygen ions in the material respectively, and can be obtained from the distribution function of ion i:

[0027] In solid oxides, the conductivity σ is jointly determined by the movement of h · , and . Then, we have:

[0028] σ = ec H u H + 2ec O u O + ec h u h = eξu h + e(u H - u h )C H + 2e(u O - u h)c V (Equation 7);

[0029] e is the charge amount of the elementary charge, c h is the hole concentration, u h , u O and u H are respectively h · , and ion mobilities;

[0030] Substituting Equation 6 into Equation 7 gives the time distribution function of the conductivity when the water partial pressure changes, which can be simplified to:

[0031] σ(t) = σ(∞) - σ H f H (D H，chem , t) + σ O f O (D o，chem，t ) (Equation 8);

[0032] σ(∞) is the electronic conductivity at the equilibrium state when t → ∞, σ H and σ O is an intermediate quantity reflecting the influence degrees of proton migration and oxygen ion migration on the conductivity, and its magnitude is related to their ion mobilities, f i (D i，chem , t) is a function related to the i ion concentration distribution:

[0033]

[0034] tanα i，m = L i，x , β i，n tanβ i，n = L i，y , γ i，l tanγ i，l = L i，z , i = (O, H) (Equation 11);

[0035] Thus, a diffusion equation for the conductivity varying with time containing the D H，chem and D O，chem parameters is established, and fitting it can obtain the proton diffusion coefficient.

[0036] A test device based on the proton migration rate of solid oxides includes a gas cylinder, a volume flowmeter, a water vapor generator, a quartz glass tube, a temperature control unit, a heating wire, an exhaust gas treatment device, a conductivity test device, and a data processing unit;

[0037] The gas cylinder provides a protective atmosphere for the device;

[0038] The volumetric flowmeter is arranged on the connecting pipeline between the gas cylinder and the steam generator;

[0039] The steam generator is used to provide steam for the quartz glass tube after changing the atmosphere;

[0040] The temperature control unit is used to monitor the temperature of the quartz glass tube and control the heating furnace wire to heat the quartz glass tube;

[0041] The tail gas treatment device is the outlet of the quartz tube, which is used to discharge argon and water vapor inside the quartz glass tube to balance the air pressure;

[0042] The conductivity test device is used to record the current and voltage readings in real time;

[0043] The data processing unit is used for data fitting.

[0044] Advantageous Effects

[0045] By regulating the water partial pressure in the atmosphere where the material is located and monitoring in real time the change law of conductivity with time during this process, the present invention obtains the bulk proton migration kinetic parameters, and quantitatively studies the bulk proton migration rate of the triple-conductive material from the perspective of reaction kinetics; realizes the direct quantitative evaluation of the proton migration rate. Using the test method of the present invention, the bulk proton migration rates of various triple-conductive materials can be tested, which is conducive to further revealing the relevant mechanisms of the triple-conductive electrode and providing a theoretical basis for the design and modification of the oxygen electrode. This method has the following advantages:

[0046] (1) Accurate quantification: By directly observing the change of conductivity, the precise quantitative evaluation of the proton migration rate can be realized, avoiding the uncertainty brought by theoretical calculation.

[0047] (2) Simple operation: This method does not require complex experimental equipment and cumbersome operation steps, and is easy to be popularized and applied in laboratory and industrial environments.

[0048] (3) Wide application range: This method is applicable to various types of materials, including proton conductors, triple-conductive materials, etc., and provides a more applicable scheme for the evaluation of the proton migration rate. Description of the Drawings

[0049] Figure 1 It is a schematic diagram of the device provided by the present invention.

[0050] Figure 2 For Example 1, the conductivity change curve of the Sr2Fe 1.5 Mo 0.5 O 6-δ triple-conductive material after changing the water partial pressure at 700 °C.

[0051] Figure 3For Example 2, after changing the water partial pressure at 550 °C, the conductivity change curve of the triple-conductive material BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ is shown.

[0052] Figure 4 For Example 3, after changing the water partial pressure at 750 °C, the Arrhenius curve of the proton diffusion coefficient fitted for the triple-conductive material PrBa 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5+δ is shown.

[0053] Figure 5 For Example 4, after changing the water partial pressure at 600 °C, the conductivity change curve of the proton-conductive material PrNi 0.5 Co 0.5 O 3-δ is shown.

[0054] Figure 6 For Example 5, after changing the water partial pressure at 600 °C, the conductivity change curve of the proton-conductive material BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 is shown.

[0055] Figure 7 For Example 1, after changing the water partial pressure at 750 - 600 °C, the Arrhenius curve of the proton diffusion coefficient fitted for the triple-conductive material Sr2Fe 1.5 Mo 0.5 O 6-δ is shown. Specific Embodiments

[0056] The present invention will be further described in detail below in conjunction with specific embodiments.

[0057] As Figure 1 shown, a test device for the proton migration rate based on solid oxides includes a gas cylinder 1, a volume flowmeter 2, a water vapor generator 3, a quartz glass tube 4, a temperature control unit 5, a heating wire 6, an exhaust gas treatment device 7, a conductivity test device 8, and a data processing unit 9;

[0058] The gas cylinder 1 provides a protective atmosphere for the device;

[0059] The volume flowmeter 2 is arranged on the connecting pipeline between the gas cylinder 1 and the water vapor generator 3;

[0060] The water vapor generator 3 is used to provide water vapor for the quartz glass tube 4 after changing the atmosphere;

[0061] The temperature control unit 5 is used to monitor the temperature of the fused silica tube 4 and control the heating furnace wire 6 to heat the fused silica tube 4;

[0062] The tail gas treatment device 7 is the outlet of the quartz tube, which is used to discharge the argon and water vapor inside the fused silica tube 4 to balance the air pressure;

[0063] The conductivity test device 8 is used to record the current and voltage readings in real time;

[0064] The data processing unit 9 is used for data fitting.

[0065] Example 1: A method for measuring the proton migration rate in Sr2Fe 1.5 Mo 0.5 O 6-& is as follows:

[0066] (1) Using Sr(NO3)2·6H2O, Fe(No3)3·9H2O, (NH4)6Mo7O 24 ·4H2O, (NH4)6W7O 24 ·4H2O as the cation source, dissolve it in 500 ml of deionized water, add 10 g of glycine and 10 g of anhydrous citric acid. Stir well in a water bath at 80 °C until it dissolves into a clear mixed solution, stir until it becomes a brownish-yellow gel state, heat it in a forced-air drying oven at 250 °C for 2 h to form a fluffy and porous black precursor, grind it into powder with a mortar and place it in a crucible. Sinter it in a muffle furnace at 1100 °C for 5 h to obtain a solid oxide sample powder.

[0067] (2) Take the sample powder and 5% PVA binder in a mass ratio of 2:1, re-grind it into powder, put it into a briquetting mold, apply pressure for 5 min, remove the pressure and take out the sample bar from the mold, put it into a muffle furnace and calcine it for 2 h. After cooling to room temperature, a cuboid sample bar with a final relative density > 95% is obtained. The sample to be measured has three-dimensional dimensions of 2a×2b×2c.

[0068] (3) Wind four silver wires around the sample bar to divide the sample bar into five equal parts for current collection. After bonding and fixing them with silver paste respectively, place the four silver wires in four ceramic tubes respectively, fix the four ceramic tubes with silver wires and place them in a tube furnace. Sinter them at 750 °C for 30 min and then cool to room temperature.

[0069] (4) Set the operating program of the conductivity meter and record 25,000 points in total to ensure the integrity of the data.

[0070] (5) Heat up to the set temperature of 700 °C in an argon atmosphere. After stabilizing for 30 min, run the conductivity meter program to start recording the readings. After 40 min, change the water partial pressure (90% Ar + 10% H2O) by regulating the steam generator until the program ends.

[0071] (6) Data processing: Take the data after the atmosphere starts to change, perform fitting calculations on it, and obtain D H = 3.56×10 - 6 cm 2 ·s -1 ; The conductivity change curve is as Figure 2 shown.

[0072] Figure 7 is the Arrhenius curve of the proton diffusion coefficient fitted for the triple-conductive material Sr2Fe 1.5 Mo 0.5 O 6-δ under the condition of changing the water partial pressure at 750 - 600 °C in Example 1, which is used for the influence of temperature on the proton diffusion coefficient, and the energy barrier (reaction activation energy) required to overcome proton migration can be obtained by fitting it.

[0073] Example 2: A method for measuring the proton migration rate in BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ is as follows:

[0074] (1) Using Ba(NO3)2, Co(NO3)2·6H2O, Fe(NO3)3·9H2O, Zr(NO3)2·2H2o, Y(No3)3·6H2O as cation sources, dissolve them in 500 ml of deionized water, add 10 g of ethylenediaminetetraacetic acid and 10 g of anhydrous citric acid. Stir well in a water bath at 80 °C until it dissolves into a clear mixed solution, stir until it becomes a brown-yellow gel state, heat it in a forced-air drying oven at 250 °C for 2 h to form a fluffy and porous black precursor, grind it into powder with a mortar and place it in a crucible. Sinter it in a muffle furnace at 1100 °C for 5 h to obtain a solid oxide sample powder.

[0075] (2) Take the sample powder with a mass ratio of 2:1 and 5% PVA binder, re-grind it into powder, put it into a briquetting mold, apply pressure for 5 min, remove the pressure and take out the sample bar from the mold, put it into a muffle furnace and calcine it for 2 h. After cooling to room temperature, obtain a final cuboid sample bar with a relative density > 95%. The sample to be measured has three-dimensional dimensions of 2a×2b×2c.

[0076] (3) Wind four silver wires around the sample strip respectively to divide the sample strip into five equal parts for current collection. After bonding and fixing them with silver paste respectively, place the four silver wires into four ceramic tubes respectively, fix the four ceramic tubes with silver wires and place them in a tube furnace. After sintering at 750 °C for 30 min, cool down to room temperature.

[0077] (4) Set the operating program of the conductivity meter and record 25,000 points in total to ensure the integrity of the data.

[0078] (5) Heat up to the set temperature of 550 °C in an argon atmosphere. After stabilizing for 30 min, run the conductivity meter program to start recording the readings. After 40 min, change the water partial pressure (90% Ar + 10% H2O) by adjusting the steam generator until the program ends.

[0079] (6) Data processing: Take the data after the atmosphere starts to change, perform fitting calculations on it, and obtain D H =7.85×10 - 7 cm 2 ·s -1 ;The conductivity change curve is as Figure 3 shown.

[0080] Example 3: A method for measuring the proton migration rate in PrBa 0.5 Sr 0.5 Co 1.5 Fe 0.5 O 5+δ is as follows:

[0081] (1) Using Pr(NO3)3·6H2O, Ba(NO3)2, Sr(NO3)2·6H2O, Co(NO3)2·6H2O, Fe(NO3)3·9H2O as cation sources, dissolve them in 500 ml of deionized water, add 10 g of glycine and 10 g of anhydrous citric acid. Stir well in a water bath at 80 °C until it dissolves into a clear mixed solution, stir until it becomes a brown-yellow gel state, heat it in a forced-air drying oven at 250 °C for 2 h to form a fluffy and porous black precursor, grind it into powder with a mortar and place it in a crucible. Sinter it in a muffle furnace at 1100 °C for 5 h to obtain a solid oxide sample powder.

[0082] (2) Take the sample powder and 5% PVA binder with a mass ratio of 2:1, re-grind them into powder, put them into a briquetting mold, apply pressure for 5 min, remove the pressure and take out the sample strip from the mold, put it into a muffle furnace and calcine it for 2 h. After cooling to room temperature, obtain a final cuboid sample strip with a relative density > 95%. The dimension of the sample to be measured is 2a×2b×2c in three dimensions.

[0083] (3) Four silver wires were respectively wound around the sample strip to divide the sample strip into five equal parts for current collection, and they were respectively bonded and fixed with silver paste. Then, the four silver wires were respectively placed in four ceramic tubes, and the four ceramic tubes were fixed with silver wires and placed in a tube furnace. After sintering at 750°C for 30 minutes, the temperature was cooled to room temperature.

[0084] (4) Set the conductivity meter operation program and record a total of 25,000 points to ensure data integrity.

[0085] (5) The temperature was raised to the set temperature of 750°C in an argon atmosphere. After stabilization for 30 minutes, the conductivity meter program was run to start recording the readings. After 40 minutes, the water partial pressure (90% Ar + 10% H2O) was changed by adjusting the water vapor generator until the program ended.

[0086] (6) Data processing: Take the data after the atmosphere starts to change, perform fitting calculation on it, and obtain D H =8.04×10 - 5 cm 2 ·s -1 ; The conductivity change curve is as follows Figure 4 shown.

[0087] Example 4: A method for measuring PrNi 0.5 Co 0.5 O 3-δ The method for calculating the proton migration rate in the medium is as follows:

[0088] (1) Pr(NO3)3·6H2O, Ni(NO3)2·6H2O, and Co(NO3)2·6H2O were used as cation sources and dissolved in 500 ml of deionized water. 10 g of glycine and 10 g of anhydrous citric acid were added. The mixture was fully stirred in an 80°C water bath to dissolve into a clear mixed solution. The mixture was stirred until it became a brown-yellow gel state. The mixture was heated in a 250°C forced air drying oven for 2 h to form a fluffy, porous black precursor. The precursor was ground into powder in a mortar and placed in a crucible. The solid oxide sample powder was obtained by sintering in a muffle furnace at 1100°C for 5 h.

[0089] (2) Take the sample powder and 5% PVA binder in a mass ratio of 2:1, grind them into powder again, put them into a stripping mold, apply pressure for 5 minutes, remove the sample strip from the mold after pressure relief, put it into a muffle furnace and calcine it for 2 hours. After cooling to room temperature, the final rectangular sample strip with a density of >95% is obtained. The sample to be tested has a three-dimensional size of 2a×2b×2c.

[0090] (3) Wind four silver wires around the sample strip respectively to divide the sample strip into five equal parts for current collection. After bonding and fixing them with silver paste respectively, place the four silver wires into four ceramic tubes respectively, fix the four ceramic tubes with silver wires and place them in a tube furnace. After sintering at 750 °C for 30 min, cool down to room temperature.

[0091] (4) Set the operating program of the conductivity meter and record 25,000 points in total to ensure the integrity of the data.

[0092] (5) Heat up to the set temperature of 750 °C in an argon atmosphere. After stabilizing for 30 min, run the conductivity meter program to start recording the readings. After 40 min, change the water vapor pressure (90% Ar + 10% H2O) by adjusting the water vapor generator until the program ends.

[0093] (6) Data processing: Take the data after the atmosphere starts to change, perform fitting calculations on it, and obtain D H = 3.57×10 - 5 cm 2 ·s -1 ; The conductivity change curve is as Figure 5 shown.

[0094] Example 5: A method for measuring the proton migration rate in BaZr 0.4 Ce 0.4 Y 0.1 Yb 0.1 O 3-δ is as follows:

[0095] (1) Place BaCO3, ZrO2, CeO2, Y2O3, and Yb2O3 in a ball mill tank according to the corresponding stoichiometric ratios, add an appropriate amount of ethanol and ball milling beads, and ball mill at a speed of 450 r·min -1 for about 4 h to obtain a precursor. After taking it out, place it in an oven to dry. After taking out the ball milling beads, place the sample in a crucible and sinter it in a muffle furnace at 1100 °C for 10 h to obtain BZCYYb4411 powder. In order to obtain a pure-phase electrolyte material, repeat the ball milling and drying steps and sinter it again in a muffle furnace at 1300 °C for 10 h to obtain a stable and pure-phase sample powder. Grind it thoroughly again for later use.

[0096] (2) Take the sample powder and 5% PVA binder with a mass ratio of 2:1, re-grind it into powder, put it into a briquetting mold, apply pressure for 5 min, remove the pressure and take out the sample strip from the mold, put it into a muffle furnace and calcine it for 2 h. After cooling to room temperature, obtain a final cuboid sample strip with a relative density > 95%. The sample to be measured has three-dimensional dimensions of 2a×2b×2c.

[0097] (3) Wind four silver wires around the sample strip respectively to divide the sample strip into five equal parts for current collection. After bonding and fixing them with silver paste respectively, place the four silver wires into four ceramic tubes respectively, fix the four ceramic tubes with silver wires and place them in a tube furnace. Sinter at 750 °C for 30 min and then cool down to room temperature.

[0098] (4) Set the operating program of the conductivity meter and record 25,000 points in total to ensure the integrity of the data.

[0099] (5) Heat up to the set temperature of 700 °C in an argon atmosphere. After stabilizing for 30 min, run the conductivity meter program to start recording the readings. After 40 min, change the water vapor pressure (90% Ar + 10% H2O) by adjusting the water vapor generator until the program ends.

[0100] (6) Data processing: Take the data after the atmosphere starts to change, perform fitting calculations on it, and obtain D H = 4.03×10 - 6 cm 2 ·s -1 ; The conductivity change curve is as Figure 6 shown.

[0101] In summary, the invention includes but is not limited to the above embodiments. Any equivalent replacement or partial improvement carried out under the spirit and principle of the present invention will be regarded as within the protection scope of the present invention.

Claims

1. A test method based on the proton migration rate of solid oxides, characterized in that: The method steps include: (1) Mix the solid oxide with a binder, grind, press, and calcine to obtain a rectangular parallelepiped sample bar with a relative density > 95%; (2) Uniformly wind and fix one end of multiple silver wires along the length direction on the sample bar respectively, then place the sample bar in a tubular furnace and connect it to a conductivity meter, while ensuring insulation between the silver wires; sinter at 750 - 800 °C for 30 - 120 min and then cool down; (3) Under the atmosphere of a protective gas, after the temperature in the tubular furnace stabilizes at the set temperature, introduce water vapor into the tubular furnace, and measure the conductivity of the sample bar at different water partial pressures through the conductivity meter; (4) Based on the conductivity results, combine Fick's second diffusion law and the charge balance equation to establish a diffusion equation of conductivity varying with time containing the proton bulk diffusion coefficient, and fit to obtain the proton migration rate of the solid oxide.

2. The test method based on the proton migration rate of solid oxide materials according to claim 1, characterized in that: In step (1), the binder is PVA, and the addition amount is 5% - 10% of the total mass of the mixed system; press for 5 - 10 min under a pressure of 15 - 20 MPa, and then calcine in a muffle furnace at 1100 - 1200 °C for 2 - 3 h.

3. The test method based on the proton migration rate of solid oxide substances according to claim 1, characterized in that: In step (2), fix the silver wires on the sample bar through silver paste; and / or place the silver wires in a ceramic tube and fix them in the tubular furnace to ensure insulation between the silver wires.

4. The test method based on the proton migration rate of solid oxide substances according to claim 1, characterized in that: In step (3), the protective gas is nitrogen or an inert gas.

5. The test method based on the proton migration rate of solid oxide materials according to claim 1, characterized in that: In step (3), the set temperature is 550 - 750 °C.

6. The test method based on the proton migration rate of solid oxide substances as described in claim 1, wherein: In step (3), based on the total volume of the protective gas and water vapor in the tubular furnace being 100%, the volume fraction of water vapor is 3% - 10%.

7. The test method based on the proton migration rate of solid oxide materials according to claim 1, wherein: In step (4), assume the three-dimensional dimensions of the sample strip are 2a × 2b × 2c. Using the conductivity readings detected in real time, combined with Fick's second law of diffusion: Among them, C i is the concentration distribution of the i-th ion, is the bulk diffusion coefficient of the i-th ion. When i is O, it represents the oxygen ion, and when i is H, it represents the proton; At t = 0, the sample is already in equilibrium, and the concentrations of all ions are known constants. Therefore, the initial conditions can be obtained: C i (x, o) = C i,0 (Equation 2); Since both oxygen ions and protons diffuse from the sample surface to the center position of the rectangular parallelepiped sample, and the concentration distribution is symmetric, at any moment, the concentration change rate at the center position of the sample is 0. Therefore, in the x-axis direction, there is: On the surface of the sample strip, the concentrations of oxygen ions and protons both originate from the transformation of water molecules on the sample surface. Assuming that within the given range of oxygen partial pressure and the change in the measured water partial pressure, the conversion coefficient of water molecules on the sample is constant, then, in combination with Fick's first law of diffusion, an equation is established with the ion transport flux. There are boundary conditions in the x-axis direction: Among them, is the conversion coefficient of water molecules on the sample surface, C i，∞ is the concentration distribution of ion i under the equilibrium state; Successively replace x in formula 1 to formula 4 with y, z, and a with b, c, to obtain the corresponding diffusion equations, initial conditions, and boundary conditions in the y and z-axis directions, thereby obtaining the diffusion equations of oxygen ions and protons in three-dimensional space; According to the charge balance equation in the oxide, we have: c h = ξ - c H - 2c O (Equation 5); where ξ is the total charge of the local charges at all cation positions in the sample bar material, c h is the hole concentration, c H and c O are the average concentrations of protons and oxygen ions in the material, respectively, and can be obtained from the distribution function of ion i: In solid oxides, the conductivity σ is jointly determined by the movement of h, and such that: σ = ec H u H + 2ec O u O + ec h u h = eξu h + e(u H - u h )C H + 2e(u O - u h )c V (Equation 7); e is the electric charge of the elementary charge, c h is the hole concentration, u h 、u O and u H are respectively h, and ion mobilities of; Substituting Equation 6 into Equation 7 gives the time distribution function of conductivity when the water partial pressure changes, which can be simplified to: σ(t) = σ(∞) - σ H f H (D H，chem , t) + σ O f O (D o,chem , t) (Equation 8); σ(∞) is the electronic conductivity at the equilibrium state when t → ∞, and σ H and σ O is an intermediate quantity reflecting the influence degrees of proton migration and oxygen ion migration on the conductivity. Its magnitude is related to their ionic mobilities, and f i (D i,chem , t) is a function related to the concentration distribution of ion i: tanα i，m = L i，x , β i，n tanβ i，n = L i，y , γ i，l tanγ i,l = L i，z , i = (O, H) (Equation 11); Thus, a diffusion equation for the change of conductivity with time containing the parameters D H,chem and D O，chem is established, and the proton diffusion coefficient can be obtained by fitting it.

8. A test device for the proton migration rate of a solid oxide material used in the method according to any one of claims 1 to 7, characterized in that: It includes a gas cylinder (1), a volume flowmeter (2), a water vapor generator (3), a quartz glass tube (4), a temperature control unit (5), a heating furnace wire (6), an exhaust gas treatment device (7), a conductivity test device (8), and a data processing unit (9); The gas cylinder (1) provides a protective atmosphere for the device; The volume flowmeter (2) is arranged on the connecting pipeline between the gas cylinder (1) and the water vapor generator (3); The water vapor generator (3) is used to provide water vapor for the quartz glass tube (4) after changing the atmosphere; The temperature control unit (5) is used to monitor the temperature of the quartz glass tube (4) and control the heating furnace wire (6) to heat the quartz glass tube (4); The exhaust gas treatment device (7) is the outlet of the quartz tube, used to discharge argon and water vapor inside the quartz glass tube (4) and balance the air pressure; The conductivity test device (8) is used to record the current and voltage readings in real time; The data processing unit (9) is used for data fitting.

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