Enhanced hydrogen electrode supporting body, hydrogen electrode supporting SOC unit and preparation method

Abstract

The invention provides an enhanced hydrogen electrode supporting body, a hydrogen electrode supporting SOC unit and a preparation method. The hydrogen electrode supporting SOC unit comprises an enhanced hydrogen electrode supporting body, an electrolyte layer, a barrier layer and an oxygen electrode layer, and the enhanced hydrogen electrode supporting body is subjected to a high-proportion zirconia ceramic phase superposition catalytic component modification process, so that the mechanical strength of the supporting body is improved, and the surface electrochemical performance and conductivity of the supporting body are enhanced; the electrolyte layer can be directly applied to the enhanced hydrogen electrode support body without a hydrogen electrode functional layer, so that the process flow is shortened, the material cost and the SOC unit thickness are reduced, and the yield is high. The method is applied to the field of hydrogen electrode supporting SOC units and hydrogen electrode supporting SOC stacks.

Description

Technical Field

[0001] The present invention relates to the technical field of solid oxide fuel cells (SOFC) and solid oxide electrolyzers (SOEC), and in particular to a hydrogen electrode support, a hydrogen electrode support SOC unit and a preparation method thereof, and is applicable to the fields of sheet-type SOC unit manufacturing and stacking modules, fuel cell power generation and water electrolysis hydrogen production. Background Art

[0002] SOFC is an efficient and clean energy conversion device. It is a power generation device that directly converts the chemical energy of fuel into electrical energy in an efficient, low-carbon and environmentally friendly manner at medium and high temperatures. It is currently the most efficient new energy technology route for power generation in the world. As a highly anticipated new generation of water electrolysis device, SOEC is a relatively advanced and forward-looking hydrogen production technology that can effectively utilize waste heat and stably provide low-carbon electricity. It has the advantages of high flexibility, long life, low cost, and the use of industrial waste heat.

[0003] Solid oxide cells (SOCs) can be divided into hydrogen electrode supported SOCs, electrolyte supported SOCs and metal supported SOCs according to the different supports. Among them, hydrogen electrode supported SOCs have certain advantages in terms of operating temperature, electrochemical properties, ease of mass production and manufacturing cost.

[0004] The general process of hydrogen electrode support SOC unit is to cast the support, screen print the hydrogen electrode functional layer and electrolyte layer on the support in sequence, co-sinter, screen print the isolation layer and oxygen electrode again, and sinter them separately. Due to differences in application process, coating ratio, and material expansion coefficient, the co-sintering process of the support, electrode functional layer, and electrolyte layer is relatively complex and has a low yield rate.

[0005] The hydrogen electrode support generally uses nickel oxide and doped zirconium oxide as the main materials. The reduced nickel plays a catalytic and conductive role, and the doped zirconium oxide serves as a ceramic skeleton to provide mechanical support. The common mass ratio of nickel oxide and doped zirconium oxide ranges from 40:60 to 60:40. A higher proportion of nickel oxide helps to improve the electrochemical performance of the battery, but it may also bring problems such as sintering and stability. On the contrary, a higher proportion of zirconium oxide helps to enhance the structural stability and sintering ability of the anode, but may reduce the electrochemical activity to a certain extent. The sintering temperature of nickel oxide is between 800 and 1200°C, and the sintering temperature of doped zirconium oxide is between 1200 and 1600°C. When the quality difference is small, it is difficult for nickel oxide and doped zirconium oxide to obtain a two-phase sintered body with excellent mechanical properties. Summary of the invention

[0006] The task of the present invention is to overcome the deficiencies of the above technologies and to provide a reinforced hydrogen electrode support, a hydrogen electrode support SOC unit and a preparation method.

[0007] The present invention is accomplished by the following technical solutions: An enhanced hydrogen electrode support is provided, which is composed of nickel oxide, doped zirconium oxide, aluminum oxide and modified components, and the mass proportion of each component is: nickel oxide 20-40%, doped zirconium oxide 55-75%, aluminum oxide 0-5%, and modified components (excluding nickel components) 0-5%.

[0008] A hydrogen electrode support SOC unit is provided, comprising a reinforced hydrogen electrode support, an electrolyte layer, a barrier layer and an oxygen electrode layer.

[0009] A method for preparing a hydrogen electrode support SOC unit is provided, wherein a high proportion of zirconia ceramics, i.e., an initial support body, is prepared by a tape casting and sintering process, the initial support body is then impregnated and modified with a catalytic component to obtain a reinforced hydrogen electrode support body, and then an electrolyte layer, a barrier layer and an oxygen electrode layer are prepared in sequence.

[0010] Compared with the prior art, the present invention has the following advantages or effects: The present invention provides a reinforced hydrogen electrode support, a hydrogen electrode support SOC unit and a preparation method thereof. The initial support single layer is degreased and sintered, thereby solving the problem of low yield due to differences in coating ratios of different embryos and material expansion coefficients. The reinforced hydrogen electrode support is modified by a high-proportion zirconium oxide ceramic superimposed catalytic component modification process, thereby improving the mechanical strength of the support and enhancing the electrochemical properties and conductivity of the support surface. An electrolyte layer can be directly applied to the reinforced hydrogen electrode support without a hydrogen electrode functional layer, thereby shortening the process flow and reducing material costs and SOC unit thickness. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the cross-sectional structure in the thickness direction of the hydrogen electrode supporting SOC unit proposed in the present invention.

[0012] Figure 2 It is a schematic diagram of the process flow of the method for preparing a hydrogen electrode supported SOC unit proposed in the present invention.

[0013] The present invention is further described in detail below in conjunction with the accompanying drawings. DETAILED DESCRIPTION

[0014] Provide an enhanced hydrogen electrode support with a thickness of 200~1000μm. The material is composed of nickel oxide, doped zirconium oxide, aluminum oxide and modified components. The mass proportion of each component is: nickel oxide 20~40%, doped zirconium oxide 55~75%, aluminum oxide 0~5%, and modified components (excluding nickel components) 0~5%.

[0015] The doping element of the doped zirconium oxide is at least one of yttrium, scandium, ytterbium and cerium, and the doping concentration is ≥5.5 mol%.

[0016] The modifying component is one or more of nickel compounds, iron compounds, cobalt compounds, copper compounds, metal gold, gold compounds, metal silver, silver compounds, metal platinum, platinum compounds, metal palladium, palladium compounds, metal rhodium, rhodium compounds, metal ruthenium, ruthenium compounds, tungsten compounds, and molybdenum compounds.

[0017] A hydrogen electrode support SOC unit is provided with a thickness of 210-1075 μm, including a reinforced hydrogen electrode support, an electrolyte layer, a barrier layer and an oxygen electrode layer.

[0018] The electrolyte layer has a thickness of 3-20 μm, preferably 5-10 μm, and the electrolyte material is doped zirconium oxide, the doping element is at least one of yttrium, scandium, ytterbium, and cerium, and the doping concentration is ≥8 mol%.

[0019] The thickness of the barrier layer is 0.5-5 μm, preferably 0.5-2 μm, and the barrier layer material is doped cerium oxide, and the doping element is gadolinium and / or samarium.

[0020] The thickness of the oxygen electrode layer is 5-50 μm, preferably 10-35 μm, and the material of the oxygen electrode layer is at least two of doped cerium oxide, lanthanum strontium cobalt iron, lanthanum strontium manganese, lanthanum strontium cobalt, lanthanum nickel cobalt, metal gold, gold oxide, metal silver, silver oxide, metal platinum, platinum oxide, metal palladium, palladium oxide, metal rhodium, rhodium oxide.

[0021] Provide a method for preparing a hydrogen electrode supporting SOC unit, refer to Figure 2 : S01 Casting high proportion zirconium oxide initial support green body, nickel oxide, doped zirconium oxide, aluminum oxide, organic solvent and auxiliary materials are mixed, ground, filtered and degassed to form an initial support casting slurry, which is cast on a PET film belt, dried at 30-150°C for 1-3 hours, and cut to obtain the initial support green body sheet. The cutting size is determined according to the unit demand and shrinkage rate, without any specific constraints and restrictions.

[0022] S02 Degreasing and sintering: sinter the cut green sheets at 1200-1500°C for 1-4 hours to obtain high-proportion zirconium oxide initial support ceramic sheets.

[0023] S03 impregnation modification, drying and calcination, the modification component raw materials and the solvent are stirred, dissolved and mixed, the initial support body is placed in the impregnation modification solution for vacuum impregnation for 1 to 3 hours, dried at 60 to 120°C for 1 to 3 hours, and calcined at 200 to 800°C for 1 to 4 hours. The impregnation, drying and calcination can be repeated many times to obtain an enhanced hydrogen electrode support body.

[0024] S04 prepares the electrolyte layer, mixes and grinds the doped zirconium oxide, organic solvent and auxiliary materials to form an electrolyte slurry, screen prints it on the enhanced hydrogen electrode support, dries it at 25-65°C for 0.5-2 hours, and sinters it at 1200-1500°C for 1-4 hours.

[0025] S05 prepares the barrier layer, mixes and grinds the doped cerium oxide, organic solvent and auxiliary materials to form a barrier layer slurry, performs screen printing operation on the electrolyte layer, dries at 25-65°C for 0.5-2 hours, and sintered at 1200-1300°C for 1-4 hours.

[0026] S06 prepares an oxygen electrode, mixes and grinds the oxygen electrode material, the organic solvent and the auxiliary agent to form a barrier layer slurry, performs screen printing operation on the electrolyte layer, dries at 25-65°C for 0.5-2 hours, and sintered at 900-1200°C for 1-4 hours.

[0027] A hydrogen electrode supporting SOC unit is obtained.

[0028] In some embodiments, the organic solvent for casting is selected from methanol, anhydrous ethanol, toluene, xylene, isopropanol, acetone, butanone, ethyl acetate and butyl acetate, and the auxiliary agent is selected from polyvinyl butyral, acrylic resin, ethyl cellulose and methyl cellulose, dibutyl phthalate, dioctyl phthalate, oleic acid and cyclohexanone, starch, activated carbon, and graphite.

[0029] In some embodiments, the modification component raw material is selected from soluble nickel salts, iron salts, cobalt salts, copper salts, gold salts, silver salts, platinum salts, palladium salts, rhodium salts, ruthenium salts, tungsten salts, and molybdenum salts, and the modification immersion solution solvent is selected from deionized water, methanol, anhydrous ethanol, and acetone.

[0030] In some embodiments, the organic solvent for screen printing electrolyte, barrier layer, and oxygen electrode is selected from ethanol, pineol, tributyl citrate, ethyl acetate, butyl acetate, and butyl carbitol, and the auxiliary agents are selected from polyvinyl butyral, polyvinyl alcohol, acrylic resin, ethyl cellulose and methyl cellulose, dibutyl phthalate, fish oil, castor oil, oleic acid, span, graphite, carbon powder, polymethyl methacrylate, and starch. Example

[0031] S01 Casting high proportion zirconium oxide initial support green body, 460g nickel oxide, 1500g 8YSZ, 40g alumina, 850g anhydrous ethanol, 850g xylene, 170g polyvinyl butyral, 50g dibutyl phthalate, 40g fish oil, 20g cyclohexanone are mixed, ground, filtered, and degassed to form a casting slurry, and the casting operation is performed on a PET film tape with a casting thickness of 300μm. Dry at 30~150℃ for 2 hours, cut into 130mm×190mm size to obtain the initial support green body sheet.

[0032] S02 Degreasing and sintering: sinter the cut green sheets at 1400°C for 2 hours to obtain high-proportion zirconium oxide initial support ceramic sheets.

[0033] S03 impregnation modification, drying and calcination. 291g nickel nitrate hexahydrate, 48g copper nitrate trihydrate, 118g hydrated ammonium paratungstate and 2000ml anhydrous ethanol are stirred, dissolved and mixed. The initial support ceramic piece is placed in the impregnation modification solution and vacuum impregnated for 3 hours, dried at 85°C for 2 hours, and calcined at 400°C for 2 hours. The impregnation, drying and calcination operations are repeated twice to obtain an enhanced hydrogen electrode support.

[0034] S04 Prepare the electrolyte layer: mix and grind 50g 8YSZ, 4g ethyl cellulose, 25g pine alcohol, 8g butyl carbitol, and 1g fish oil to form an electrolyte slurry, screen print it on the enhanced hydrogen electrode support, with a thickness of 12μm, dry it at 25~65℃ for 2 hours, and sinter it at 1370℃ for 2 hours.

[0035] S05 Prepare the barrier layer: mix and grind 50g GDC, 4g ethyl cellulose, 25g pine alcohol, 8g butyl carbitol, and 1g fish oil to form a barrier layer slurry, screen print it on the electrolyte layer, dry it at 25-65℃ for 2 hours, and sinter it at 1250℃ for 1 hour.

[0036] S06 Prepare oxygen electrode: 28g lanthanum strontium manganese powder, 22g GDC, 4.0g PMMA, 4g ethyl cellulose, 25g pinene alcohol, 10g butyl carbitol, and 1.0g fish oil are mixed and ground to form oxygen electrode slurry, which is screen-printed on the barrier layer, dried at 25-65°C for 2 hours, and sintered at 1000°C for 2 hours.

[0037] A hydrogen electrode supporting SOC unit is obtained.

[0038] As described above, the present invention can be better implemented. The above embodiments are only the best implementation methods of the present invention, but the implementation methods of the present invention are not limited by the above embodiments. Other changes, modifications, replacements, combinations, and simplifications made without departing from the spirit and principle of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. Hydrogen electrode support SOC unit, thickness 210 ~ 1075μm, including a reinforced hydrogen electrode support, an electrolyte layer, a barrier layer and an oxygen electrode layer.

2. The hydrogen electrode supporting SOC unit according to claim 1, characterized in that: The reinforced hydrogen electrode support has a thickness of 200 to 1000 μm. The material is composed of nickel oxide, doped zirconium oxide, aluminum oxide and modified components. The mass proportion of each component is: nickel oxide 20 to 40%, doped zirconium oxide 55 to 75%, aluminum oxide 0 to 5%, and modified components (excluding nickel components) 0 to 5%.

3. The enhanced hydrogen electrode support according to claim 2, characterized in that: The doping element of the doped zirconium oxide is at least one of yttrium, scandium, ytterbium and cerium, and the doping concentration is ≥5.5 mol%.

4. The enhanced hydrogen electrode support according to claim 2, characterized in that: The modifying component is one or more of nickel compounds, iron compounds, cobalt compounds, copper compounds, metal gold, gold compounds, metal silver, silver compounds, metal platinum, platinum compounds, metal palladium, palladium compounds, metal rhodium, rhodium compounds, metal ruthenium, ruthenium compounds, tungsten compounds, and molybdenum compounds.

5. The hydrogen electrode supporting SOC unit according to claim 1, characterized in that: The electrolyte layer has a thickness of 3 to 20 μm, preferably 5 to 10 μm, the electrolyte material is doped zirconium oxide, the doping element is at least one of yttrium, scandium, ytterbium and cerium, and the doping concentration is ≥8 mol%.

6. The hydrogen electrode supporting SOC unit according to claim 1, characterized in that: The thickness of the barrier layer is 0.5 to 5 μm, preferably 0.5 to 2 μm. The barrier layer material is doped cerium oxide, and the doping element is gadolinium and / or samarium.

7. The hydrogen electrode supporting SOC unit according to claim 1, characterized in that: The thickness of the oxygen electrode layer is 5 to 50 μm, preferably 10 to 35 μm, and the material of the oxygen electrode layer is at least two of doped cerium oxide, lanthanum strontium cobalt iron, lanthanum strontium manganese, lanthanum strontium cobalt, lanthanum nickel cobalt, metal gold, gold oxide, metal silver, silver oxide, metal platinum, platinum oxide, metal palladium, palladium oxide, metal rhodium, rhodium oxide.

8. A method for preparing a hydrogen electrode supported SOC unit, characterized in that: The following steps are involved: S01 Casting high-proportion zirconium oxide initial support green body, mixing nickel oxide, doped zirconium oxide, aluminum oxide, organic solvent and auxiliary materials, grinding, filtering, degassing to form initial support casting slurry, casting operation on PET film belt, drying and cutting; S02 degreasing and sintering, sintering the cut green sheets at 1200-1500℃ for 1-4 hours; S03 impregnation modification, drying, and calcination, stirring, dissolving, and mixing the modified component raw materials and the solvent, placing the initial support body in the impregnation modification solution for vacuum impregnation for 1 to 3 hours, drying at 60 to 120° C. for 1 to 3 hours, and calcining at 200 to 800° C. for 1 to 4 hours, and repeating the impregnation, drying, and calcination operations for ≥ 1 time; S04 prepares the electrolyte layer, mixes and grinds the doped zirconium oxide, the organic solvent and the auxiliary materials to form an electrolyte slurry, performs screen printing operation on the enhanced hydrogen electrode support, and sintered at 1200-1500° C. for 1-4 hours; S05 prepares the barrier layer, mixes and grinds the doped cerium oxide, the organic solvent and the auxiliary materials to form a barrier layer slurry, performs screen printing operation on the electrolyte layer, dries, and sintered at 1200-1300° C. for 1-4 hours; S06 prepares the oxygen electrode, mixes and grinds the oxygen electrode material, the organic solvent and the auxiliary agent to form a barrier layer slurry, performs screen printing operation on the electrolyte layer, dries, and sinters at 900-1200° C. for 1-4 hours.

9. The method for preparing a hydrogen electrode supporting SOC unit according to claim 8, characterized in that: The raw materials of the modified components are selected from soluble nickel salts, iron salts, cobalt salts, copper salts, gold salts, silver salts, platinum salts, palladium salts, rhodium salts, ruthenium salts, tungsten salts, and molybdenum salts, and the modified impregnation solution solvent is selected from deionized water, methanol, anhydrous ethanol, and acetone.

10. A chip-type SOC stack module composed of 2 or more SOC units described in claim 1 and / or claim 2 and / or claim 8, and its application in power generation and hydrogen production by water electrolysis.

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