Method for preparing proton conductor solid oxide electrolytic tank by adopting ultrafast high-temperature sintering

Abstract

The invention provides a method for preparing a proton conductor solid oxide electrolytic tank by adopting ultrafast high-temperature sintering, which comprises the following steps: S1, respectively preparing a negative electrode green body, a positive electrode green body and a proton conductor electrolyte diaphragm green body by adopting a tape casting method, and carrying out lamination and hot pressing to obtain a total battery green body comprising a negative electrode, an electrolyte diaphragm and a positive electrode; s2, discharging glue from the total battery green body to obtain a glue-discharged green body; and S3, placing between two electrodes connected with a direct-current power supply, enabling the positive electrode and the negative electrode to be in close contact with the green body, turning on the power supply in a constant-current mode, enabling the current intensity applied to the two ends of the green body after glue removal to be 0.1-20A / cm < 2 >, heating and sintering at an ultra-fast rate of 500-2000DEG C / min, electrifying for 1-600s, and cooling to obtain the proton conductor solid oxide electrolytic tank. The method greatly shortens the sintering time, and effectively inhibits element volatilization of the electrolyte and interface diffusion and chemical reaction between the electrolyte and the positive and negative electrodes.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of high-temperature electrochemical devices, and particularly relates to a method for preparing a proton conductor solid oxide electrolysis cell by using ultrafast high-temperature sintering. BACKGROUND

[0002] A proton conductor solid oxide electrolysis cell (PCEC) is an electrochemical device based on a high-temperature proton-conducting ceramic electrolyte separator, which can be combined with renewable energy to use surplus power to electrolyze water vapor to produce green hydrogen. Under the catalysis of the negative electrode, the green hydrogen can further react with carbon dioxide to generate high-value chemicals. BaCeO3-BaZrO3 solid solution (such as BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ ) has high chemical stability and thermal stability, and has become a widely studied proton-conducting solid oxide electrolyte material. A PCEC electrolysis cell is composed of a dense proton-conducting solid oxide electrolyte separator and a porous negative electrode and a porous positive electrode located on the two sides of the separator. The negative electrode is mostly a metal ceramic (such as NiO-BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ ) composed of NiO and proton conductor electrolyte material, and the positive electrode is generally an electron-oxygen ion-proton triple-conducting oxide (such as PrNi 0.5 Co 0.5 O 3–δ , BaGd 0.8 La 0.2 Co2O 6-δ , La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ , and Sm 0.5 Sr 0.5 CoO 3-δ , etc.

[0003] In order to reduce the conduction resistance of protons in the electrolyte separator, the electrolysis cell often adopts a negative electrode supported thin film electrolyte structure. The preparation process of the electrolysis cell generally includes two steps: first, a negative electrode supported thin film electrolyte green body is prepared, and is co-sintered at 1350-1500 DEG C and kept for 1-6 hours to obtain a dense electrolyte separator; and second, a positive electrode is coated on the surface of the dense electrolyte separator, and is calcined at 900-1200 DEG C to obtain a negative electrode supported full cell. BaZr 0.1 Ce 0.7 Y 0.2 O 3–δFor example, the electrolyte has the following problems: (1) during high-temperature co-sintering, BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ Ba element in the electrolyte is easy to volatilize, and there is interface diffusion between NiO and BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ , which leads to changes in chemical composition of the electrolyte membrane, reduction of proton conductivity, and increase of internal resistance of the electrolyte membrane; (2) the dense electrolyte membrane supported by the negative electrode is an asymmetric structure, and due to large difference between thermal sintering shrinkage and thermal expansion behavior of the negative electrode and the electrolyte, the half-cell with the asymmetric structure is easy to deform during high-temperature co-sintering, which affects production yield; (3) in order to prevent interface diffusion and chemical reaction between the oxide positive electrode and the electrolyte membrane, the calcination temperature of the positive electrode is low, which leads to low interface bonding strength between the positive electrode and the electrolyte membrane, and the positive electrode is easy to peel off and fall off from the surface of the electrolyte membrane. SUMMARY

[0004] Therefore, the present application aims to provide a method for preparing a proton conductor solid oxide electrolysis cell by using ultrafast high-temperature sintering, which greatly shortens sintering time and effectively inhibits element volatilization of the electrolyte and interface diffusion and chemical reaction between the electrolyte and the positive and negative electrodes.

[0005] The present application provides a method for preparing a proton conductor solid oxide electrolysis cell by using ultrafast high-temperature sintering, comprising the following steps:

[0006] S1, using a tape casting method, respectively preparing a negative electrode green body, a positive electrode green body and a proton conductor electrolyte membrane green body, and obtaining a full cell green body comprising the negative electrode, the electrolyte membrane and the positive electrode through lamination and hot pressing;

[0007] S2, degreasing the full cell green body to obtain a degreased green body;

[0008] S3, placing the degreased green body between two electrodes connected with a direct current power supply, and making the positive and negative electrodes tightly contact with the green body, turning on the power supply, and the working state of the power supply is constant current mode, the current intensity applied between the two ends of the degreased green body is 0.1-20 A / cm 2 , and the degreased green body is heated and sintered under the current at an ultrafast rate of 500-2000 ℃ / min, the power-on time is 1-600 s, and after sintering is completed, the temperature is lowered to obtain a proton conductor solid oxide electrolysis cell.

[0009] Preferably, the sintering temperature is 1000-1600 ℃;

[0010] The sintering atmosphere is any one of vacuum, air, hydrogen, hydrogen and argon mixture, nitrogen, hydrogen and nitrogen mixture.

[0011] Preferably, the electrolyte separator is selected from one or more of BaCeO 3–δ ; BaZrO 3–δ ; BaZr 0.4 Sc 0.6 O 3–δ ; BaZr 1-x-y Ce x Y y O 3–δ (x = 0.1-0.9, y = 0.1-0.9); Sr2Sc 1+x Nb 1–x O 6–δ (x = 0.1-0.9); Ba3Ca 1+ x Nb 2–x O9(x = 0.1-1.9); Ba5R2Al2SnO 13 , R = Gd, Dy, Ho, Y, Er, Tm or Yb; La 5.5 WO 11.25–δ ; La 2- x Mg x Ce2O 7-δ (x = 0.1-1.9); La 2-x Ca x Ce2O 7-δ (x = 0.1-1.9); and La 2-x K x Ce2O 7-δ (x = 0.1-1.9).

[0012] Preferably, both the negative and positive electrodes independently comprise an electron-conducting phase, a proton-conducting phase and a thermal expansion coefficient adjusting phase;

[0013] The thermal expansion coefficient of the thermal expansion coefficient adjusting phase is less than the thermal expansion coefficient of the electrolyte separator, and the difference between the thermal expansion coefficient of the negative and positive electrodes and the thermal expansion coefficient of the electrolyte separator is less than 30%, respectively.

[0014] Preferably, the electron-conducting phase is selected from NiO, Fe3O4, Co3O4, stainless steel, TiC, WC, (Ti,Nb)3SiC2, La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ , PrNi 0.5 Co 0.5 O 3-δ, Sm 0.8 Sr 0.2 CoO 3-δ , La 0.6 Sr 0.4 CoO 3-δ , Ba 0.5 Sr 0.5 Co 0.2 Fe 0.8 O 3-δ , SmBa 0.5 Sr 0.5 Co2O 5+δ , LaBa 0.5 Sr 0.5 Co2O 5+δ , SmBaCo2O 5+δ , BaGd 0.8 La 0.2 Co2O 6-δ , Sr2Fe 1.5 Mo 0.5 O 6-δ , (La 1-x Sr x )(Cr 1-y Fe y )O 3-δ (x = 0.1 to 0.9, y = 0.1 to 0.9), (La 1-x Sr x )(Cr 1-y Mn y )O 3-δ (x = 0.1 to 0.9, y = 0.1 to 0.9), (La 1-x Sr x )TiO 3-δ (x = 0.1 to 0.9), La 2-x Sr x Fe 2-y-z Ni y Mo z O 6-δ (x = 0.1 to 1.9, y = 0.1 to 0.9, z = 0.1 to 0.9).

[0015] Preferably, the proton-conducting phase is selected from the group consisting of doped BaCeO 3–δ ; doped BaZrO 3–δ ; BaZr 0.4 Sc 0.6 O 3–δ ; BaZr 1-x- y Ce x Y y O 3–δ(x=0.1-0.9, y=0.1-0.9); Sr2Sc 1+x Nb 1–x O 6–δ (x=0.1-0.9); Ba3Ca 1+x Nb 2–x O9(x=0.1-1.9); Ba5R2Al2SnO 13 , R=Gd, Dy, Ho, Y, Er, Tm or Yb; La 5.5 WO 11.25–δ ; La 2-x Mg x Ce2O 7-δ (x=0.1-1.9); La 2-x Ca x Ce2O 7-δ (x=0.1-1.9); and La 2-x K x Ce2O 7-δ (x=0.1-1.9)

[0016] Preferably, the thermal expansion coefficient adjusting phase is selected from Mg2Al4Si5O 18 , Al6Si2O 13 , Al2TiO5, KZr2P3O 12 , Zr2P2O9, CaZr4(PO4)6, Ca 0.5 Sr 0.5 Zr4(PO4)6, KZr2P3O 12 , MgAl2O4, Y2W3O 12 , Al2W3O 12 , ZrMgMo3O 12 , Zr2P2WO 12 , ZrMo2O8, ZrW2O8.

[0017] Preferably, the porosity of the negative and positive electrodes is 1-70%.

[0018] Preferably, the inner walls of the pores of the positive and negative electrodes are covered with a nano-catalyst;

[0019] The nano-catalyst is selected from Ni; Fe; Co; FeNi3; doped cerium oxide; La 0.6 Sr 0.4 CoO 3-δ ;

[0020] Sm 0.8 Sr 0.2 CoO 3-δ ; PrNi 0.5 Co 0.5 O3-δ ; La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ ; Ba 0.5 Sr 0.5 Co 0.2 Fe 0.8 O 3-δ ;

[0021] SmBa 0.5 Sr 0.5 Co2O 5+δ ; LaBa 0.5 Sr 0.5 Co2O 5+δ ; SmBaCo2O 5+δ ; BaGd 0.8 La 0.2 Co2O 6-δ ; Sr2Fe 1.5 Mo 0.5 O 6-δ ; La 2-x Sr x Fe 2-y-z Ni y Mo z O 6-δ (x = 0.1-1.9, y = 0.1-0.9, z = 0.1-0.9); BaZr 0.4 Sc 0.6 O 3–δ ; BaZr 1-x-y Ce x Y y O 3–δ (x = 0.1-0.9, y = 0.1-0.9); Sr2Sc 1+x Nb 1–x O 6–δ (x = 0.1-0.9); Ba3Ca 1+x Nb 2–x O9(x = 0.1-1.9); Ba5R2Al2SnO 13 , R = Gd, Dy, Ho, Y, Er, Tm or Yb; La 5.5 WO 11.25–δ ; La 2-x Mg x Ce2O 7-δ (x = 0.1-1.9); La 2-x Ca x Ce2O 7-δ (x = 0.1-1.9); La 2-x K x Ce2O7-δ at least one of (x = 0.1-1.9).

[0022] Preferably, the material of the two electrodes connected with the direct current power source is selected from a metal material with a melting point higher than 1800℃; or an alloy material with a melting point higher than 1800℃; or a graphite material.

[0023] The present application provides a method for preparing a proton conductor solid oxide electrolysis cell by using ultrafast high-temperature sintering, comprising the following steps: S1, preparing a negative electrode green body, a positive electrode green body and a proton conductor electrolyte diaphragm green body respectively by using a tape casting method, and obtaining a full cell green body containing a negative electrode, an electrolyte diaphragm and a positive electrode through laminating and hot pressing; S2, degreasing the full cell green body to obtain a degreased green body; S3, placing the degreased green body between two electrodes connected with a direct current power source, and making the positive and negative electrodes tightly contact with the green body, turning on the power source, and the working state of the power source is a constant current mode, the current intensity applied to both ends of the degreased green body is 0.1-20 A / cm 2 , and the degreased green body is heated and sintered under the current at an ultrafast rate of 500-2000 ℃ / min, the current time is 1-600 s, and after sintering is completed, the temperature is lowered to obtain a proton conductor solid oxide electrolysis cell. The method greatly shortens the sintering time, and effectively inhibits the behaviors such as element volatilization of the electrolyte, interface diffusion and chemical reaction between the positive and negative electrodes. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A cross-sectional schematic diagram of a full ceramic structure proton conductor solid oxide electrolysis cell prepared by ultrafast high-temperature sintering for the present application embodiment 1;

[0025] Figure 2 An element scanning diagram of a comparative sample prepared by using a traditional high-temperature sintering method for the present application comparative example;

[0026] Figure 3 A water electrolysis hydrogen production performance curve of the proton conductor solid oxide electrolysis cell after impregnating a nano catalyst for the present application embodiment 2;

[0027] Figure 4 A cross-sectional schematic diagram of a metal-supported proton conductor solid oxide electrolysis cell prepared by ultrafast high-temperature sintering for the present application embodiment 3;

[0028] Figure 5 A water electrolysis hydrogen production performance curve of the proton conductor solid oxide electrolysis cell after impregnating a nano catalyst for the present application embodiment 4. DETAILED DESCRIPTION

[0029] The present application provides a method for preparing a proton conductor solid oxide electrolysis cell by using ultrafast high-temperature sintering, comprising the following steps:

[0030] S1, a casting method is adopted to respectively prepare a negative electrode green body, a positive electrode green body and a proton conductor electrolyte separator green body, and a full battery green body comprising a negative electrode, an electrolyte separator and a positive electrode is obtained through lamination and hot pressing;

[0031] S2, the full battery green body is degreased to obtain a degreased green body;

[0032] S3, the degreased green body is placed between two electrodes connected with a direct current power supply, and the positive and negative electrodes are in close contact with the green body, the power supply is turned on, the working state of the power supply is constant current mode, and the current intensity applied to the two ends of the degreased green body is between 0.1 and 20 A / cm 2 The degreased green body is heated and sintered under current at a superfast rate of 500-2000 ℃ / min, the current time is 1-600 s, and the sintering is completed, and then the temperature is lowered to obtain a proton conductor solid oxide electrolysis cell.

[0033] The method provided by the application solves the problems of long sintering time, prominent interface diffusion and chemical reaction in the traditional preparation process, that is, the method greatly shortens the sintering time and effectively inhibits the element volatilization of the electrolyte and the interface diffusion and chemical reaction between the electrolyte and the positive and negative electrodes.

[0034] The application adopts a casting method to respectively prepare a negative electrode green body, a positive electrode green body and a proton conductor electrolyte separator green body, and a full battery green body comprising a negative electrode, an electrolyte separator and a positive electrode is obtained through lamination and hot pressing.

[0035] The method for casting the negative electrode green body or the positive electrode green body is adopted; the positive electrode raw material or the negative electrode raw material and graphite powder are mixed, a solvent and a dispersing agent are added, ball milling is carried out, a binder and a plasticizing agent are added again, ball milling is carried out again, and a casting slurry is obtained; the casting slurry is filtered and defoamed, and then casting is carried out on a substrate, and drying is carried out, so as to obtain the negative electrode green body or the positive electrode green body.

[0036] In the application, the solvent is a two-component solvent of dimethylbenzene and butyl acetate, the mass ratio of dimethylbenzene and butyl acetate is 2:1-2:4, the dispersing agent is an acrylic resin dispersing agent, the binder is polyvinyl butyral, and the plasticizing agent is polyethylene glycol and / or diethyl phthalate. The ball milling time is 22-26 h, and the re-ball milling time is 22-26 h. The thickness of the positive electrode green body is 10-300 μm, and the thickness of the negative electrode green body is 10-300 μm.

[0037] The application adopts a flow casting method to prepare a proton conductor electrolyte diaphragm green body; electrolyte raw materials, a solvent and a dispersing agent are mixed, a binder and a plasticizer are added after ball milling, electrolyte flow casting slurry is obtained after ball milling again, filtration and defoaming, and the electrolyte flow casting slurry is flow cast on a substrate to obtain a proton conductor electrolyte diaphragm green body. In the application, the solvent used to prepare the proton conductor electrolyte diaphragm green body is a two-component solvent of xylene and butyl acetate, the mass ratio of xylene to butyl acetate is 2:1-2:4; the dispersing agent is an acrylic resin dispersing agent; the binder is polyvinyl butyral; and the plasticizer is polyethylene glycol and / or diethyl phthalate.

[0038] In the application, the electrolyte diaphragm is dense, and the thickness is 1-50 μm, specifically 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 6 μm, 17 μm, 8 μm, 19 μm, 20 μm, 21 μm, 2 μm, 23 μm, 24 μm, 25 μm, 26 μm, 7 μm, 8 μm, 9 μm, 30 μm, 31 μm, 32 μm, 3 μm, 34 μm, 5 μm, 36 μm, 37 μm, 38 μm, 9 μm, 40 μm, 1 μm, 42 μm, 43 μm, 44 μm, 45 μm, 46 μm, 47 μm, 48 μm, 49 μm or 50 μm; preferably 5-15 μm.

[0039] The full battery green body prepared in the application comprises a plurality of layers of negative electrode green bodies, a plurality of layers of positive electrode green bodies and one layer of electrolyte diaphragm green body; preferably the green bodies are stacked in the order of a plurality of layers of negative electrode green bodies | one layer of electrolyte diaphragm green body | a plurality of layers of positive electrode green body and then hot pressed. The number of layers of the plurality of layers is preferably 3-10 layers, specifically 3 layers, 4 layers, 5 layers, 6 layers, 7 layers, 8 layers, 9 layers or 10 layers.

[0040] In the application, the temperature of the hot pressing is 55-85 ℃, the pressure of the hot pressing is 20-50 MPa, and the time of the hot pressing is 30-60 min.

[0041] The negative electrode and the positive electrode each independently comprise an electron conductive phase, a proton conductive phase and a thermal expansion coefficient adjusting phase; the thermal expansion coefficient of the thermal expansion coefficient adjusting phase is less than the thermal expansion coefficient of the electrolyte diaphragm, and the difference between the thermal expansion coefficient of the negative electrode and the thermal expansion coefficient of the electrolyte diaphragm is less than 30%, and the difference between the thermal expansion coefficient of the positive electrode and the thermal expansion coefficient of the electrolyte diaphragm is less than 30%.

[0042] In the application, the value of δ in the material containing δ is related to the values of x and y.

[0043] The electron conductive phase in the present invention is selected from at least one of NiO, Fe3O4, Co3O4, stainless steel, TiC, WC, (Ti, Nb)3SiC2, La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ , PrNi 0.5 Co 0.5 O 3-δ , Sm 0.8 Sr 0.2 CoO 3-δ , La 0.6 Sr 0.4 CoO 3-δ , Ba 0.5 Sr 0.5 Co 0.2 Fe 0.8 O 3-δ , SmBa 0.5 Sr 0.5 Co2O 5+δ , LaBa 0.5 Sr 0.5 Co2O 5+δ , SmBaCo2O 5+δ , BaGd 0.8 La 0.2 Co2O 6-δ , Sr2Fe 1.5 Mo 0.5 O 6-δ , (La 1-x Sr x )(Cr 1-y Fe y )O 3-δ (x = 0.1 ~ 0.9, y = 0.1 ~ 0.9), (La 1-x Sr x )(Cr 1-y Mn y )O 3-δ (x = 0.1 ~ 0.9, y = 0.1 ~ 0.9), (La 1-x Sr x )TiO 3-δ (x = 0.1 ~ 0.9), La 2-x Sr x Fe 2-y-z Ni y Mo z O 6-δ (x = 0.1 ~ 1.9, y = 0.1 ~ 0.9, z = 0.1 ~ 0.9).

[0044] The proton conductive phase in the present invention is selected from doped BaCeO3–δ ; doped BaZrO 3–δ ; BaZr 0.4 Sc 0.6 O 3–δ ; doped BaZrO 1-x- y Ce x Y y O 3–δ (x=0.1-0.9, y=0.1-0.9); Sr2Sc 1+x Nb 1–x O 6–δ (x=0.1-0.9); Ba3Ca 1+x Nb 2–x O9(x=0.1-1.9); Ba5R2Al2SnO 13 , R=Gd, Dy, Ho, Y, Er, Tm or Yb; La 5.5 WO 11.25–δ ; La 2-x Mg x Ce2O 7-δ (x=0.1-1.9); La 2-x Ca x Ce2O 7-δ (x=0.1-1.9); and La 2-x K x Ce2O 7-δ (x=0.1-1.9)

[0045] The thermal expansion coefficient adjusting phase in the present invention is selected from at least one of Mg2Al4Si5O 18 , Al6Si2O 13 , Al2TiO5, KZr2P3O 12 , Zr2P2O9, CaZr4(PO4)6, Ca 0.5 Sr 0.5 Zr4(PO4)6, KZr2P3O 12 , MgAl2O4, Y2W3O 12 , Al2W3O 12 , ZrMgMo3O 12 , Zr2P2WO 12 , ZrMo2O8, ZrW2O8.

[0046] In the present invention, the negative electrode and the positive electrode are preferably both Sr2Fe 1.5 Mo 0.5 O 6-δ -BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ-ZrMo2O8, or 430L-BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ -Al2TiO5. The electrolyte separator is BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ .

[0047] After obtaining the full cell green body, the full cell green body is degreased to obtain a degreased green body. The degreasing temperature is 500-1000°C; preferably, the temperature is raised at a rate of 0.5°C / min; preferably, the temperature is maintained at 180°C, 250°C, 350°C and 900°C for 110-130 min respectively; after the degreasing is completed, the temperature is lowered at a rate of 2.5-3.5°C / min to a certain temperature, preferably 550-600°C, and then the furnace is naturally cooled to room temperature.

[0048] The degreased green body is placed between two electrodes connected with a direct current power source, and the positive and negative electrodes are in close contact with the green body. The power source is turned on, and the working state of the power source is constant current mode. The current intensity applied to the two ends of the degreased green body is 0.1-20 A / cm 2 , and the degreased green body is heated and sintered under the current at an ultrafast rate of 500-2000°C / min. The power-on time is 1-600 s, and then the temperature is lowered after sintering to obtain a proton conductor solid oxide electrolysis cell.

[0049] The material of the two electrodes connected with the direct current power source in the application is selected from a metal material with a melting point higher than 1800°C; or an alloy material with a melting point higher than 1800°C; or a graphite material.

[0050] The current limiting value is adjusted to make the current intensity applied to the two ends of the degreased green body be 0.1-20 A / cm 2 , and the current intensity can be 0.1 A / cm 2 , 0.5 A / cm 2 , 1 A / cm 2 , 2 A / cm 2 , 3 A / cm 2 , 4 A / cm 2 , 5 A / cm 2 , 6 A / cm 2 , 7 A / cm 2 , 8 A / cm 2 , 9 A / cm 2 , 10 A / cm 2 , 11 A / cm 2 , 12 A / cm 2 , 13 A / cm2 , 14 A / cm 2 , 15 A / cm 2 , 16 A / cm 2 , 17 A / cm 2 , 18 A / cm 2 , 19 A / cm 2 or 20 A / cm 2 .

[0051] The present application is heated at an ultrafast rate of 500-2000℃ / min, which can be specifically 500℃ / min, 550℃ / min, 600℃ / min, 650℃ / min, 700℃ / min, 750℃ / min, 800℃ / min, 850℃ / min, 900℃ / min, 950℃ / min, 1000℃ / min, 1050℃ / min, 1100℃ / min, 1150℃ / min, 1200℃ / min, 1250℃ / min, 1300℃ / min, 1350℃ / min, 1400℃ / min, 1450℃ / min, 1500℃ / min, 1550℃ / min, 1600℃ / min, 1650℃ / min, 1700℃ / min, 1750℃ / min, 1800℃ / min, 1850℃ / min, 1900℃ / min, 1950℃ / min or 2000℃ / min.

[0052] The green body after the glue is discharged is heated and sintered under the current, and the current time is 1-600s; which can be specifically 1s, 5s, 10s, 50s, 100s, 150s, 200s, 250s, 300s, 350s, 400s, 450s, 500s, 550s, 600s, 650s, 700s, 750s, 800s, 850s, 900s, 950s or 1000s.

[0053] The sintering temperature in the present application is 1000-1600℃, which can be specifically 1000℃, 1050℃, 1100℃, 1150℃, 1200℃, 1250℃, 1300℃, 1350℃, 1400℃, 1450℃, 1500℃, 1550℃ or 1600℃.

[0054] The sintering atmosphere in the present application is any one of vacuum, air, hydrogen, hydrogen and argon mixed gas, nitrogen, hydrogen and nitrogen mixed gas.

[0055] In the present application, the porosity of the negative electrode and the positive electrode is 1-70%, which can be specifically 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65% or 70%; preferably 20-40%.

[0056] The present application carries out the loading of nano catalysts after ultrafast high-temperature sintering; the present application preferably realizes the loading through the way of impregnation; in the present application, the inner wall of the holes of the positive electrode and the negative electrode is covered with nano catalysts; the kind of the nano catalysts loaded in the holes of the positive electrode and the negative electrode can be consistent or inconsistent. The ratio of the weight of the impregnated catalyst to the weight of the corresponding electrode empty skeleton is 10-15:100.

[0057] The nano catalysts are selected from Ni; Fe; Co; FeNi3; doped cerium oxide; La 0.6 Sr 0.4 CoO 3-δ ;

[0058] Sm 0.8 Sr 0.2 CoO 3-δ ; PrNi 0.5 Co 0.5 O 3-δ ; La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ ; Ba 0.5 Sr 0.5 Co 0.2 Fe 0.8 O 3-δ ;

[0059] SmBa 0.5 Sr 0.5 Co2O 5+δ ; LaBa 0.5 Sr 0.5 Co2O 5+δ ; SmBaCo2O 5+δ ; BaGd 0.8 La 0.2 Co2O 6-δ ; Sr2Fe 1.5 Mo 0.5 O 6-δ ; La 2-x Sr x Fe 2-y-z Ni y Mo z O 6-δ (x=0.1-1.9, y=0.1-0.9, z=0.1-0.9); BaZr 0.4 Sc 0.6 O 3–δ ; BaZr 1-x-y Ce x Y y O 3–δ(x=0.1~0.9, y=0.1~0.9); Sr2Sc 1+x Nb 1–x O 6–δ (x=0.1~0.9); Ba3Ca 1+x Nb 2–x O9(x=0.1~1.9); Ba5R2Al2SnO 13 , R=Gd, Dy, Ho, Y, Er, Tm or Yb; La 5.5 WO 11.25–δ ; La 2-x Mg x Ce2O 7-δ (x=0.1~1.9); La 2-x Ca x Ce2O 7-δ (x=0.1~1.9); La 2-x K x Ce2O 7-δ (x=0.1~1.9). In specific embodiments, the nano catalyst is preferably NiO-Gd 0.1 Ce 0.9 O 2-δ nano negative catalyst or PrNi 0.5 Co 0.5 O 3-δ nano catalyst.

[0060] The present application promotes the rapid and efficient electrolysis of water by placing nano catalysts in the pores of the negative and positive electrodes. The present application is sintered into a phase after impregnating the nano catalyst; the sintering temperature is 700~1000℃, and can be specifically 700℃, 750℃, 800℃, 850℃, 900℃, 950℃, 1000℃; the sintering time is 1h~5h, and can be specifically 1h, 1.5h, 2.0h, 2.5h, 3h, 3.5h, 4h, 4.5h or 5h.

[0061] In order to further illustrate the present application, a method for preparing a proton conductor solid oxide electrolysis cell using ultrafast high temperature sintering provided by the present application is described in detail below in conjunction with examples, but they should not be understood as limiting the scope of protection of the present application.

[0062] Example 1

[0063] The electrolyte diaphragm in this embodiment is BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ , the positive electrode and the negative electrode are both Sr2Fe 1.5 Mo 0.5 O 6-δ-BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ -ZrMo2O8, the electrolyte separator green body is prepared by the following steps:

[0064] 1) Sr2Fe 1.5 Mo 0.5 O 6-δ , BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ , ZrMo2O8 and graphite powder are added into a ball milling barrel, then dimethylbenzene and butyl acetate two-component solvent and acrylic resin dispersant are added, after ball milling for 24 h, a binder and a plasticizer are added, and ball milling is carried out for another 24 h to obtain a uniformly dispersed casting slurry; after filtration and defoaming, the slurry is cast on a Mylar film and dried to obtain a ≈60-micron-thick Sr2Fe 1.5 Mo 0.5 O 6-δ -BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ -ZrMo2O8, respectively as the negative electrode green body and the positive electrode green body;

[0065] 2) BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ ceramic powder are added into a ball milling barrel, then dimethylbenzene and butyl acetate two-component solvent and acrylic resin dispersant are added, after ball milling for 24 h, a binder and a plasticizer are added, and ball milling is carried out for another 24 h to obtain a uniformly dispersed casting slurry. After filtration and defoaming, the slurry is cast on a Mylar film and dried to obtain a ≈15-micron-thick BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ electrolyte separator green body;

[0066] 3) 6 layers of Sr2Fe 1.5 Mo 0.5 O 6-δ -BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ -ZrMo2O8 negative electrode green body | 1 layer of BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ electrolyte separator green body | 6 layers of Sr2Fe 1.5 Mo0.5 O 6-δ -BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ After stacking the ZrMo2O8 positive electrode green body, the whole body was isostatically pressed at 75°C and 7000psi for 30min to obtain an electrolytic cell green body;

[0067] 4) Raise the temperature of the electrolytic cell green body to 900°C at 0.5°C / min, and keep it at 180, 250, 350, and 900°C for 2 hours each. After debinding, cool it down to 600°C at 3°C / min, and cool it naturally to room temperature in the furnace.

[0068] 5) The debinded electrolytic cell green body was placed between two carbon felt heating electrodes connected to a DC power supply, ensuring close contact between the carbon felt heating electrodes and the green body. The power supply was turned on and adjusted to a constant current mode with a current of 35A. The green body was rapidly heated and sintered under the action of the current. The power was on for 10 seconds in a high-purity nitrogen atmosphere at a temperature of 1400°C. After sintering, the temperature was cooled to obtain a proton conductor solid oxide electrolytic cell.

[0069] Figure 1 This is a scanning electron microscope microstructure image of the electrolytic cell prepared by ultrafast high-temperature sintering. No obvious element interdiffusion phenomenon was found in the element scanning.

[0070] As a comparative example, Sr2Fe 1.5 Mo 0.5 O 6-δ Green and BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ Green body, thickness is 60 microns. 0.1 Ce 0.7 Y 0.2 O 3–δ Green|1 layer Sr2Fe 1.5 Mo 0.5 O 6-δ Green|6-layer BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ After stacking in a green body manner, the whole isostatically pressed at 75°C and 7000psi for 30 minutes; then the conventional sintering method is used to treat it at 1400°C for 4 hours. Figure 2 The scanning electron microscope image of the sample prepared as a comparative example shows that BaZr 0.1 Ce 0.7 Y 0.2 O 3–δCe, Y elements of the phase partially diffuse to Sr2Fe 1.5 Mo 0.5 O 6-δ Sr element of the phase partially diffuses to Sr2Fe 1.5 Mo 0.5 O 6-δ Ce, Y elements of the phase partially diffuse to Sr2Fe 1.5 Mo 0.5 O 6-δ .

[0071] Example 2

[0072] The proton conductor solid oxide electrolysis cell in this embodiment is based on the proton conductor solid oxide electrolysis cell of Example 1, further impregnating NiO-Gd in the porous Sr2Fe 1.5 Mo 0.5 O 6-δ -BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ -ZrMo2O8 negative electrode 0.1 Ce 0.9 O 2-δ nano negative electrode catalyst, in the porous Sr2Fe 1.5 Mo 0.5 O 6-δ -BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ -ZrMo2O8 positive electrode 0.5 Co 0.5 O 3-δ nano positive electrode catalyst, the impregnation amount is 10%; after the impregnation is completed, sintering at 1000°C for 5h. The negative electrode is passed through 97% H2-3% H2O, the positive electrode is passed through 20% air-80% H2O, Figure 3 is the electrolysis water hydrogen production curve of the electrolysis cell at 650°C and 600°C, wherein the current density at 650°C and 1.3V is 0.91A / cm 2 .

[0073] Example 3

[0074] The electrolyte diaphragm in this embodiment is BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ , the positive electrode and the negative electrode are both 430L-BaZr 0.1 Ce 0.7 Y 0.2 O 3–δAl2TiO5. The electrolytic cell preparation step is the same as that of Example 1, the current is set to 30 A, the current time is 15 s, the sintering temperature is 1375℃, and the sintering atmosphere is 3% H2-97% N2. Figure 4 The scanning electron microscope microstructure diagram of the super-fast high-temperature sintering prepared metal-supported proton conductor solid oxide electrolytic cell prepared for Example 3.

[0075] Example 4

[0076] The proton conductor solid oxide electrolytic cell in the present embodiment is based on the proton conductor solid oxide electrolytic cell of Example 3, and further impregnates NiO-Gd 0.1 Ce 0.7 Y 0.2 O 3–δ -Al2TiO5 negative electrode impregnated with NiO-Gd 0.1 Ce 0.9 O 2-δ nano negative electrode catalyst, and impregnates 10% in the porous 430L-BaZr 0.1 Ce 0.7 Y 0.2 O 3–δ -Al2TiO5 positive electrode impregnated with PrNi 0.5 Co 0.5 O 3-δ nano positive electrode catalyst, and the impregnation amount is 10%; after the impregnation is completed, sintering is carried out at 1000℃ for 5h. The negative electrode is connected to 97% H2-3% H2O, and the positive electrode is connected to 30% H2O-30% O2, Figure 5 The hydrogen production curve of the electrolytic cell electrolyzing water at 650℃, and the current density at 1.3V is 0.7A / cm 2 .

[0077] As can be seen from the above examples, the method for preparing a proton conductor solid oxide electrolytic cell by super-fast high-temperature sintering proposed by the present application does not need a high-temperature heating furnace, directly reaches the densification temperature zone of the electrolyte diaphragm by using super-fast heating, the sintering time is short, the element volatilization of the electrolyte is effectively inhibited, and the interface diffusion and chemical reaction between the positive electrode and the negative electrode are also inhibited, the internal resistance of the electrolyte diaphragm is reduced, the catalytic activity of the positive electrode and the negative electrode is improved, and the interface bonding strength between the positive electrode and the electrolyte is also enhanced. The energy utilization rate of the method is high, has the characteristics of wide application range, simple process, good energy-saving effect, and low cost, is suitable for large-scale preparation of large-size electrolytic cells, and has a broad application prospect.

[0078] The above only describes the preferred embodiments of the present application, and it should be noted that for ordinary skilled persons in the technical field, some improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be regarded as the protection scope of the present application.

Claims

1. A method for preparing a proton conductor solid oxide electrolytic cell using ultrafast high-temperature sintering, comprising the following steps: S1. Using a tape casting method, prepare a negative electrode green body, a positive electrode green body, and a proton conductor electrolyte membrane green body respectively, and obtain a full battery green body including a negative electrode, an electrolyte membrane, and a positive electrode by lamination and hot pressing; S2, debinding the full battery green body to obtain a debinded green body; S3, placing the debinding green body between two electrodes connected to a DC power supply, and making the positive and negative electrodes in close contact with the green body, turning on the power supply, the power supply working state is constant current mode, and the current intensity applied to both ends of the debinding green body is between 0.1 and 20A / cm 2 The temperature is raised at an ultra-fast rate of 500 to 2000°C / min. After debinding, the green body is heated and sintered under electric current. The power-on time is 1 to 600 seconds. After sintering, the temperature is lowered to obtain a proton conductor solid oxide electrolytic cell.

2. The method according to claim 1, characterized in that The sintering temperature is 1000-1600°C; The sintering atmosphere is any one of vacuum, air, hydrogen, a mixture of hydrogen and argon, nitrogen, and a mixture of hydrogen and nitrogen.

3. The method according to claim 1, characterized in that The electrolyte separator is selected from doped BaCeO 3–δ ; doped BaZrO 3–δ ;BaZr 0.4 Sc 0.6 O 3–δ ;BaZr 1-x-y Ce x Y y O 3–δ (x=0.1~0.9, y=0.1~0.9); Sr2Sc 1+x Nb 1–x O 6–δ (x=0.1~0.9);Ba3Ca 1+x Nb 2–x O9(x=0.1~1.9);Ba5R2Al2SnO 13 , R=Gd, Dy, Ho, Y, Er, Tm or Yb; La 5.5 WO 11.25–δ ;La 2-x Mg x CeO 7-δ (x=0.1~1.9);La 2-x Ca x CeO 7-δ (x=0.1~1.9); and La 2- x K x CeO 7-δ (x=0.1~1.9) or more.

4. The method according to claim 1, wherein The negative electrode and the positive electrode each independently include an electron conductive phase, a proton conductive phase and a thermal expansion coefficient adjusting phase; The thermal expansion coefficient of the thermal expansion coefficient adjusting phase is smaller than the thermal expansion coefficient of the electrolyte membrane, and the difference between the thermal expansion coefficients of the negative electrode and the positive electrode and the thermal expansion coefficient of the electrolyte membrane is less than 30%.

5. The method according to claim 4, characterized in that The electronic conductive phase is selected from NiO, Fe3O4, Co3O4, stainless steel, TiC, WC, (Ti, Nb)3SiC2, La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ 、PrNi 0.5 Co 0.5 O 3-δ 、Sm 0.8 Sr 0.2 CoO 3-δ 、La 0.6 Sr 0.4 CoO 3-δ 、Ba 0.5 Sr 0.5 Co 0.2 Fe 0.8 O 3-δ 、SmBa 0.5 Sr 0.5 Co2O 5+δ 、LaBa 0.5 Sr 0.5 Co2O 5+δ 、SmBaCo2O 5+δ 、BaGd 0.8 La 0.2 Co2O 6-δ 、Sr2Fe 1.5 Mo 0.5 O 6-δ 、(La 1-x Sr x )(Cr 1-y Fe y )O 3-δ (x=0.1~0.9, y=0.1~0.9), (La 1-x Sr x )(Cr 1-y Mn y )O 3-δ (x=0.1~0.9, y=0.1~0.9), (La 1-x Sr x )TiO 3-δ (x=0.1~0.9), La 2-x Sr x Fe 2-y-z Ni y Mo z O 6-δ At least one of (x=0.1~1.9, y=0.1~0.9, z=0.1~0.9).

6. The method according to claim 4, characterized in that The proton conducting phase is selected from doped BaCeO 3–δ ; doped BaZrO 3–δ ;BaZr 0.4 Sc 0.6 O 3–δ ;BaZr 1-x-y Ce x Y y O 3–δ (x=0.1~0.9, y=0.1~0.9); Sr2Sc 1+x Nb 1–x O 6–δ (x=0.1~0.9);Ba3Ca 1+x Nb 2–x O9(x=0.1~1.9);Ba5R2Al2SnO 13 , R=Gd, Dy, Ho, Y, Er, Tm or Yb; La 5.5 WO 11.25–δ ;La 2-x Mg x CeO 7-δ (x=0.1~1.9);La 2-x Ca x CeO 7-δ (x=0.1~1.9); and La 2- x K x CeO 7-δ (x=0.1~1.9) or more.

7. The method according to claim 4, characterized in that The thermal expansion coefficient adjusting phase is selected from Mg2Al4Si5O 18 、Al6Si2O 13 、Al2TiO5、KZr2P3O 12 、Zr2P2O9、CaZr4(PO4)6、Ca 0.5 Sr 0.5 Zr4(PO4)6、KZr2P3O 12 、MgAl2O4、Y2W3O 12 、Al2W3O 12 、ZrMgMo3O 12 、Zr2P2WO 12 , at least one of ZrMo2O8, and ZrW2O8.

8. The method according to claim 1, characterized in that The porosity of the negative electrode and the positive electrode is 1 to 70%.

9. The method according to claim 8, characterized in that The inner walls of the pores of the positive and negative electrodes are covered with nanocatalysts; The nanocatalyst is selected from Ni; Fe; Co; FeNi3; doped cerium oxide; La 0.6 Sr 0.4 CoO 3-δ ;Sm 0.8 Sr 0.2 CoO 3-δ ;PrNi 0.5 Co 0.5 O 3-δ ;La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ ; Ba 0.5 Sr 0.5 Co 0.2 Fe 0.8 O 3-δ ;SmBa 0.5 Sr 0.5 Co2O 5+δ ;LaBa 0.5 Sr 0.5 Co2O 5+δ ;SmBaCo2O 5+δ ;BaGd 0.8 La 0.2 Co2O 6-δ ;Sr2Fe 1.5 Mo 0.5 O 6-δ ;La 2-x Sr x Fe 2-y- z Ni y Mo z O 6-δ (x=0.1~1.9, y=0.1~0.9, z=0.1~0.9); BaZr 0.4 Sc 0.6 O 3–δ ;BaZr 1-x-y Ce x Y y O 3–δ (x=0.1~0.9, y=0.1~0.9); Sr2Sc 1+x Nb 1–x O 6–δ (x=0.1~0.9);Ba3Ca 1+x Nb 2–x O9(x=0.1~1.9);Ba5R2Al2SnO 13 , R=Gd, Dy, Ho, Y, Er, Tm or Yb; La 5.5 WO 11.25–δ ;La 2-x Mg x CeO 7-δ (x=0.1~1.9);La 2-x Ca x CeO 7-δ (x=0.1~1.9);La 2-x K x CeO 7-δ At least one of (x=0.1 to 1.9).

10. The method according to claim 1, characterized in that The materials of the two electrodes connected to the DC power supply are selected from metal materials with a melting point higher than 1800° C.; or alloy materials with a melting point higher than 1800° C.; or graphite materials.

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