Single crystal electrolyte sheet for SOC, single crystal electrolyte supporting SOC unit and application
By using stabilizer stabilized zirconia oxide single crystal electrolyte sheets, a single crystal electrolyte support SOC unit is formed without grain boundaries, which solves the problem of limited oxygen ion conduction, achieves efficient oxygen ion conduction and low internal resistance, and promotes the development of solid oxide fuel cells and electrolytic hydrogen production.
Patent Information
- Application Number
- CN202510640461.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-19
- Publication Date
- 2025-08-12
AI Technical Summary
In existing solid oxide batteries supported by doped zirconia electrolytes, the oxygen ion conduction ability is limited by grain boundaries and crystal energy barriers, resulting in high internal resistance of the electrolyte, poor electrochemical performance, and the partial aggregate of impurity elements at the grain boundaries affects the transmission efficiency.
A single crystal electrolyte sheet of zirconia-based oxide stable with a stabilizer is formed to form a single crystal electrolyte supporting SOC unit, avoid grain boundaries, improve oxygen ion conduction capacity, and reduce internal resistance. Six to eighteen mol% yttrium oxide or scandium oxide are used to stabilize and dopant ions to form an electrolyte structure without grain boundaries.
It significantly improves the conduction capacity of oxygen ions in the electrolyte, reduces the internal resistance of the electrolyte, improves the electrochemical performance, broadens the application field of cubic zircon, and increases added value.
Smart Images
Figure CN120465102A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of solid oxide fuel cells (SOFCs) and solid oxide electrolyzers (SOECs), and in particular to an electrolyte support and a SOC unit. The present invention is applicable to the fields of chip-type SOC units, SOC components, SOC stack modules, fuel cell power generation, and water electrolysis hydrogen production. Background Art
[0002] The Energy Law of the People's Republic of China, which came into effect on January 1, 2025, explicitly incorporates hydrogen energy into the energy management system for the first time. Hydrogen energy is a crucial component of the future national energy system and a cornerstone of building a green lifestyle. Solid oxide cells (SOCs), which include solid oxide fuel cell (SOFC) and solid oxide electrolyzer (SOEC) technologies, are essentially inverse models of each other and are important electrochemical energy conversion devices for hydrogen production and utilization.
[0003] Cubic zirconia, also known as Soviet stone, exists as a single crystal of cubic zirconium oxide. It is an important synthetic gemstone and is widely used as a diamond substitute. Industrial synthesis is primarily based on the "cold crucible" method. Individual crystals vary in size, up to the size of a basketball, and are economical.
[0004] Oxygen-ion-conducting SOCs can be categorized as hydrogen electrode-supported, electrolyte-supported, and metal-supported, depending on the support. Doped zirconia electrolyte-supported SOCs typically utilize doped zirconia powder. A polycrystalline cubic zirconia phase electrolyte layer with a thickness of 100-300 μm and a density greater than 92% is synthesized through processes such as tape casting, debinding, and sintering. Oxygen ion conduction in the electrolyte requires passage through numerous crystals, grain boundaries, and pores, overcoming crystal energy barriers, grain boundary energy barriers, and steric hindrances. Oxygen ion conductivity is often used to measure the material's oxygen ion conductivity. Existing literature indicates that the grain boundary conductivity of doped zirconia crystals is 2-3 orders of magnitude lower than the crystal conductivity, and the activation energy for conduction is over 7 kJ / mol higher. Furthermore, if impurity elements segregate at the grain boundaries, forming secondary phases or heterogeneous phases, oxygen ion transport becomes even more difficult, leading to even lower oxygen ion conductivity. Summary of the Invention
[0005] The task of the present invention is to provide a new single crystal electrolyte sheet for SOC, a single crystal electrolyte-supported SOC unit and its application in the SOC field, guide the application direction of the single crystal electrolyte-supported SOC unit and promote the development of the SOC field.
[0006] The present invention is accomplished through the following technical solutions:
[0007] A single crystal electrolyte sheet is provided. The sheet has a cubic crystal structure and contains an electrolyte component. The electrolyte component is composed of a zirconium oxide single crystal stabilized by a stabilizer and containing dopant ions.
[0008] A single crystal electrolyte-supported SOC unit is provided, including a single crystal electrolyte sheet, a hydrogen electrode, an oxygen electrode, an isolation layer, and a transition layer. The cross-sectional structural order of the SOC unit in the thickness direction is as follows: on one side of the single crystal electrolyte sheet, there are the transition layer, the isolation layer, and the oxygen electrode from near to far; on the other side of the symmetrical single crystal electrolyte sheet, there are the transition layer and the hydrogen electrode from near to far.
[0009] Compared with the prior art, the present invention has the following advantages or effects:
[0010] The present invention provides a single crystal electrolyte sheet and a single crystal electrolyte-supported SOC unit, which adopts a stable zirconia single crystal as an electrolyte support, adding a new type of SOC support. Because the electrolyte does not contain grain boundaries, the conductivity of oxygen ions in the electrolyte is greatly improved, the internal resistance of the electrolyte is reduced, and the electrochemical performance is excellent. This guides its development in the fields of fuel cell power generation and water electrolysis hydrogen production. At the same time, the application of the stable zirconia single crystal electrolyte-supported SOC unit also broadens the application field of cubic zirconia and improves the added value level of cubic zirconia. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 A schematic diagram of the cross-sectional structure of the single crystal electrolyte-supported SOC unit in the thickness direction of the present invention is shown.
[0012] Figure 2 Macroscopic photographs of two embodiments of the single crystal electrolyte sheet of the present invention are shown.
[0013] Figure 3 A macroscopic photograph of a single crystal electrolyte-supported SOC unit obtained in Example 1 of the present invention is shown.
[0014] Figure 4 A macroscopic photograph of a single crystal electrolyte-supported SOC unit obtained in Example 4 of the present invention is shown.
[0015] Figure 5 The volt-ampere characteristic curve and output power density curve of the single crystal electrolyte supported SOFC unit obtained in Example 1 of the present invention are shown.
[0016] The numbers in the accompanying drawings represent:
[0017] 11. Single crystal electrolyte sheet; 12. Hydrogen electrode; 13. Oxygen electrode; 14. Barrier layer; 15. Transition layer on the hydrogen electrode side; 16. Transition layer on the oxygen electrode side. DETAILED DESCRIPTION
[0018] A first aspect of the present invention provides a single crystal electrolyte sheet comprising an electrolyte component, having a thickness of 50 to 300 μm, and a regular shape of the electrolyte surface projected perpendicular to the thickness direction, including square, rectangular and circular shapes.
[0019] The electrolyte component is composed of a zirconium oxide stabilized by 6 to 18 mol% yttrium oxide and containing less than 2 mol% of dopant ion oxide, wherein the dopant ion is one or more of scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, gallium, germanium, bismuth, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium.
[0020] The electrolyte surface is parallel or perpendicular to the zirconium oxide single crystal plane, and the crystal plane index of the crystal plane includes (100), (010), (001), (110), (101), (111), (113),
[0021] The projected shape area is greater than or equal to 0.1 cm 2 , and less than or equal to 350cm 2 .
[0022] A second aspect of the present invention provides a single crystal electrolyte sheet comprising an electrolyte component, having a thickness of 50 to 300 μm, wherein the projection shape of the electrolyte surface perpendicular to the thickness direction is a regular shape, including a square, a rectangle and a circle.
[0023] The electrolyte component is composed of a zirconium oxide stabilized by 6 to 18 mol% scandium oxide and containing less than 5 mol% of dopant ion oxide, wherein the dopant ion is one or more of yttrium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, gallium, germanium, bismuth, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium.
[0024] The electrolyte surface is parallel or perpendicular to the zirconium oxide single crystal plane, and the crystal plane index of the crystal plane includes (100), (010), (001), (110), (101), (111), (113),
[0025] The projected shape area is greater than or equal to 0.1 cm 2 , and less than or equal to 350cm 2 .
[0026] The third aspect of the present invention provides a single crystal electrolyte-supported SOC unit, comprising a hydrogen electrode, an oxygen electrode, an isolation layer, a transition layer, and the single crystal electrolyte sheet provided in the first or second aspect above. The cross-sectional structure order of the SOC unit in the thickness direction is: on one side of the single crystal electrolyte sheet, from near to far, there are the transition layer, the isolation layer, and the oxygen electrode; on the other side of the symmetrical single crystal electrolyte sheet, from near to far, there are the transition layer and the hydrogen electrode.
[0027] The thickness of the hydrogen electrode layer is 5 to 50 μm, and the hydrogen electrode material can be selected from one or more of doped cerium oxide, doped zirconium oxide, nickel oxide, iron oxide, cobalt oxide, copper oxide, metal gold, gold oxide, metal silver, silver oxide, silver salt, metal platinum, platinum oxide, metal palladium, palladium oxide, metal rhodium, rhodium oxide, metal ruthenium, ruthenium oxide, metal iridium, iridium oxide, tungsten oxide, and molybdenum oxide.
[0028] The thickness of the oxygen electrode layer is 5 to 50 μm, and the oxygen electrode material can be selected from doped cerium oxide, doped zirconium oxide, perovskite conductive material, LnBaCo2O 5+δ (Ln=Pr, La, Gd, Sm, Nd, Y), La2Ni x Cu 1-x O 4+δ 、La2NiO 4+δ 、Pr2NiO 4+δ 、Nd2NiO 4+δ , one or more of metal gold, gold oxide, metal silver, silver oxide, silver salt, metal platinum, platinum oxide, metal palladium, palladium oxide, metal rhodium, and rhodium oxide. The perovskite-type conductive material has a general molecular formula of ABO3, wherein the A-site element can be one or more of lanthanum, praseodymium, strontium, barium, calcium, and magnesium, and the B-site element can be one or more of manganese, iron, cobalt, nickel, molybdenum, niobium, and copper.
[0029] The thickness of the isolation layer is 0-5 μm, and the isolation layer material is doped cerium oxide.
[0030] The thickness of the transition layer is 0 to 20 μm, and the transition layer material can be selected from metal oxides or metal oxide composites. The metal element can be selected from one or more of zirconium, yttrium, scandium, ytterbium, cerium, aluminum, gadolinium, samarium, nickel, iron, cobalt, copper, gold, silver, platinum, palladium, rhodium, ruthenium, iridium, tungsten and molybdenum.
[0031] The doping element of the doped cerium oxide is at least one of gadolinium, samarium, zirconium, yttrium, gallium, indium, holmium and erbium.
[0032] The doping element of the doped zirconium oxide is at least one of yttrium, scandium, cerium, ytterbium and aluminum.
[0033] In order to more clearly illustrate the solution of the present application, the present invention will be further briefly described below in conjunction with specific embodiments.
[0034] Example 1
[0035] Reference Figure 1 The single-crystal electrolyte-supported SOC cell shown in this embodiment has a six-layer structure, including a single-crystal electrolyte sheet, a hydrogen electrode, an oxygen electrode, a separator layer, and two transition layers. The cross-sectional structure of the SOC cell through its thickness is as follows: on one side of the single-crystal electrolyte sheet 11, from near to far, are the transition layer 16, separator layer 14, and oxygen electrode 13; on the other side of the symmetrical single-crystal electrolyte sheet 11, from near to far, are the transition layer 15 and hydrogen electrode 12.
[0036] The thickness of the single crystal electrolyte sheet is 80 μm, the projection shape of the electrolyte surface perpendicular to the thickness direction is circular, the electrolyte surface is parallel to the (100) crystal plane of the zirconium oxide single crystal, and the electrolyte composition is zirconium oxide stabilized by 12 mol% yttrium oxide and containing 1 mol% doped ions, and the doped ion elements are scandium, cerium and ytterbium.
[0037] The thickness of the hydrogen electrode layer is 35 μm, and the hydrogen electrode material is a mixture of gadolinium-doped cerium oxide and nickel oxide.
[0038] The thickness of the oxygen electrode layer is 40 μm, and the oxygen electrode material is gadolinium-doped cerium oxide and lanthanum strontium cobalt iron (La 0.60 Sr 0.40 Co 0.20 Fe 0.80 O 3-X ) mixture of perovskite materials.
[0039] The thickness of the isolation layer is 1.5 μm, and the isolation layer material is gadolinium-doped cerium oxide.
[0040] The thickness of the two transition layers is 2 μm, and the transition layer materials are metal oxide composites, and the metal elements are zirconium, yttrium, cerium, gadolinium and cobalt.
[0041] Example 2
[0042] The single-crystal electrolyte-supported SOC cell shown in this embodiment has a five-layer structure, including a single-crystal electrolyte sheet, a hydrogen electrode, an oxygen electrode, and two transition layers. The cross-sectional structure of the SOC cell through its thickness is as follows: on one side of the single-crystal electrolyte sheet 11, from near to far, are the transition layer 16 and the oxygen electrode 13; on the other side of the symmetrical single-crystal electrolyte sheet 11, from near to far, are the transition layer 15 and the hydrogen electrode 12.
[0043] The thickness of the single crystal electrolyte sheet is 120 μm, the projection shape of the electrolyte surface perpendicular to the thickness direction is circular, the electrolyte surface is perpendicular to the zirconium oxide single crystal plane (111), and the electrolyte composition is zirconium oxide stabilized by 8 mol% scandium oxide and containing 4 mol% doped ions, and the doped ion elements are yttrium, cerium, neodymium and cobalt.
[0044] The thickness of the hydrogen electrode layer is 35 μm, and the hydrogen electrode material is a mixture of gadolinium-doped cerium oxide and nickel oxide.
[0045] The thickness of the oxygen electrode layer is 25 μm, and the oxygen electrode material is a mixture of yttrium-stabilized zirconia and metal palladium.
[0046] The thickness of the two transition layers is 2 μm, and the materials of the transition layers are metal oxide composites, and the metal elements are zirconium and yttrium.
[0047] Example 3
[0048] The single-crystal electrolyte-supported SOC cell shown in this embodiment has a five-layer structure, including a single-crystal electrolyte sheet, a hydrogen electrode, an oxygen electrode, an isolation layer, and two transition layers. The SOC cell's cross-sectional structure through the thickness is as follows: on one side of the single-crystal electrolyte sheet 11, from near to far, are the isolation layer 14 and the oxygen electrode 13; on the other side of the symmetrical single-crystal electrolyte sheet 11, from near to far, are the transition layer 15 and the hydrogen electrode 12.
[0049] The thickness of the single crystal electrolyte sheet is 80 μm, the projection shape of the electrolyte surface perpendicular to the thickness direction is circular, the electrolyte surface is parallel to the zirconium oxide single crystal plane (100), and the electrolyte composition is zirconium oxide stabilized by 12 mol% yttrium oxide and containing 1 mol% doped ions, and the doped ion elements are yttrium, cerium, neodymium and cobalt.
[0050] The thickness of the hydrogen electrode layer is 35 μm, and the hydrogen electrode material is a mixture of gadolinium-doped cerium oxide and nickel oxide.
[0051] The thickness of the oxygen electrode layer is 40 μm, and the oxygen electrode material is gadolinium-doped cerium oxide and lanthanum strontium cobalt iron (La 0.60 Sr 0.40 Co 0.20 Fe 0.80 O 3-X ) mixture of perovskite materials.
[0052] The thickness of the isolation layer is 1.5 μm, and the isolation layer material is gadolinium-doped cerium oxide.
[0053] The thickness of the transition layer is 2 μm, and the materials of the transition layer are all metal oxide composites, and the metal elements are cerium and samarium.
[0054] Example 4
[0055] The single-crystal electrolyte-supported SOC cell shown in this embodiment has a three-layer structure, including a single-crystal electrolyte sheet, a hydrogen electrode, and an oxygen electrode. The SOC cell's cross-sectional structure, along its thickness, is organized as follows: an oxygen electrode 13 on one side of the single-crystal electrolyte sheet 11; and a hydrogen electrode 12 on the other side of the symmetrical single-crystal electrolyte sheet 11.
[0056] The thickness of the single crystal electrolyte sheet is 120 μm, the projection shape of the electrolyte surface perpendicular to the thickness direction is circular, the electrolyte surface is perpendicular to the zirconium oxide single crystal plane (111), and the electrolyte composition is zirconium oxide stabilized by 8 mol% scandium oxide and containing 4 mol% doped ions, and the doped ion elements are scandium, cerium and ytterbium.
[0057] The thickness of the hydrogen electrode layer is 35 μm, and the hydrogen electrode material is a mixture of gadolinium-doped cerium oxide and metallic platinum.
[0058] The thickness of the oxygen electrode layer is 25 μm, and the oxygen electrode material is a mixture of scandium and cerium stabilized zirconium oxide and metal palladium.
[0059] The above embodiments are only some embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Other changes, modifications, replacements, combinations, and simplifications made without departing from the spirit and principles of the present invention should be considered equivalent replacement methods and are included in the scope of protection of the present invention.
Claims
1. A single crystal electrolyte sheet for SOC, characterized in that: Contains electrolyte components, has a thickness of 50 to 300 μm, and the projection shape of the electrolyte surface perpendicular to the thickness direction is a regular shape, including square, rectangle and circle, and the projection shape area is greater than or equal to 0.1 cm 2 , and less than or equal to 350cm 2 . The electrolyte component is composed of a zirconium oxide stabilized by 6 to 18 mol% yttrium oxide and containing less than 2 mol% of dopant ion oxide, wherein the dopant ion is one or more of scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, gallium, germanium, bismuth, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium.
2. A single crystal electrolyte sheet for SOC, characterized in that: Contains electrolyte components, has a thickness of 50 to 300 μm, and the projection shape of the electrolyte surface perpendicular to the thickness direction is a regular shape, including square, rectangle and circle, and the projection shape area is greater than or equal to 0.1 cm 2 , and less than or equal to 350cm 2 . The electrolyte component is composed of a zirconium oxide stabilized by 6 to 18 mol% scandium oxide and containing less than 5 mol% of dopant ion oxide, wherein the dopant ion is one or more of yttrium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, gallium, germanium, bismuth, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium.
3. The single crystal electrolyte sheet according to claim 1 and claim 2, characterized in that: The electrolyte surface is parallel or perpendicular to the zirconium oxide single crystal plane, and the crystal plane index of the single crystal plane includes (100), (010), (001), (110), (101), (111), (113), 4. Single crystal electrolyte supported SOC unit, characterized in that: The SOC unit comprises a hydrogen electrode, an oxygen electrode, an isolation layer, a transition layer, and the single crystal electrolyte sheet according to claim 1 or claim 2, wherein the cross-sectional structural order in the thickness direction of the SOC unit is as follows: on one side of the single crystal electrolyte sheet, there are, from near to far, a transition layer, an isolation layer, and an oxygen electrode; on the other side of the symmetrical single crystal electrolyte sheet, there are, from near to far, a transition layer and a hydrogen electrode.
5. The single crystal electrolyte supported SOC unit according to claim 4, characterized in that: The thickness of the hydrogen electrode layer is 5 to 50 μm, and the hydrogen electrode material can be selected from one or more of doped cerium oxide, doped zirconium oxide, nickel oxide, iron oxide, cobalt oxide, copper oxide, metal gold, gold oxide, metal silver, silver oxide, silver salt, metal platinum, platinum oxide, metal palladium, palladium oxide, metal rhodium, rhodium oxide, metal ruthenium, ruthenium oxide, metal iridium, iridium oxide, tungsten oxide, and molybdenum oxide. The doping element of the doped cerium oxide is at least one of gadolinium, samarium, zirconium, yttrium, gallium, indium, holmium, and erbium; the doping element of the doped zirconium oxide is at least one of yttrium, scandium, cerium, ytterbium, and aluminum.
6. The single crystal electrolyte supported SOC unit according to claim 4, characterized in that: The thickness of the oxygen electrode layer is 5 to 50 μm, and the oxygen electrode material can be selected from doped cerium oxide, doped zirconium oxide, perovskite conductive material, LnBaCo2O 5+δ (Ln=Pr, La, Gd, Sm, Nd, Y), La2Ni x Cu 1-x O 4+δ 、La2NiO 4+δ 、Pr2NiO 4+δ 、Nd2NiO 4+δ , one or more of metallic gold, gold oxide, metallic silver, silver oxide, silver salt, metallic platinum, platinum oxide, metallic palladium, palladium oxide, metallic rhodium, and rhodium oxide. The doping element of the doped cerium oxide is at least one of gadolinium, samarium, zirconium, yttrium, gallium, indium, holmium, and erbium; the doping element of the doped zirconium oxide is at least one of yttrium, scandium, cerium, ytterbium, and aluminum; the molecular formula of the perovskite-type conductive material is ABO3, the A-position element can be selected from one or more of lanthanum, praseodymium, strontium, barium, calcium, and magnesium, and the B-position element can be selected from one or more of manganese, iron, cobalt, nickel, molybdenum, niobium, and copper.
7. The single crystal electrolyte supported SOC unit according to claim 4, characterized in that: The thickness of the isolation layer is 0-5 μm, and the isolation layer material is doped cerium oxide, and the doping element is at least one of gadolinium, samarium, zirconium, yttrium, gallium, indium, holmium, and erbium.
8. The single crystal electrolyte supported SOC unit according to claim 4, characterized in that: The thickness of the transition layer is 0-20 μm, and the transition layer material can be selected from metal oxides or metal oxide composites. The metal element can be selected from one or more of zirconium, yttrium, scandium, ytterbium, cerium, aluminum, gadolinium, samarium, nickel, iron, cobalt, copper, gold, silver, platinum, palladium, rhodium, ruthenium, iridium, tungsten and molybdenum.
9. Components, modules and systems constructed according to any combination of the technical features of claims 1, 2 and 4.