A mixed sodium-ion-proton conductive ceramic material, and a method of making and use thereof
By preparing Ca1-xNa1+xGaSi2O7-0.5x ceramic materials, the problem of low conductivity of electrolyte materials in solid oxide fuel cells and sodium-ion batteries was solved, achieving high efficiency of ion conductivity and proton conductivity at medium and low temperatures, which has broad application potential.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GUILIN UNIVERSITY OF TECHNOLOGY
- Filing Date
- 2024-07-03
- Publication Date
- 2026-05-12
AI Technical Summary
The electrolyte materials of existing solid oxide fuel cells have low conductivity, resulting in high operating temperatures and hindering their widespread application. Meanwhile, research on sodium-ion batteries lacks feldspar structural materials with sodium ion and proton conductivity.
A Ca1-xNa1+xGaSi2O7-0.5x ceramic material was prepared. By doping Ca with Na, the conductivity of sodium ions was improved, and the material exhibited proton conductivity under humid conditions.
Achieving high ion transport number and low conduction activation energy at medium and low temperatures improves the fuel utilization rate and theoretical electromotive force of solid oxide fuel cells, and has promising application prospects for sodium-ion batteries with high safety and high energy density.
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Figure CN118724576B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of inorganic materials and solid technology, specifically relating to a mixed sodium ion-proton conductive ceramic material, its preparation method, and its application. Background Technology
[0002] With the development of human society, the overexploitation of fossil fuels has reached its limit, while also causing serious environmental pollution problems. Therefore, it is necessary to develop new, clean, and renewable energy sources.
[0003] Solid oxide fuel cells (SOFCs) are energy conversion devices that directly and efficiently convert the chemical energy of fuel into electrical energy. Their electrolytes require high ionic conductivity and, as far as possible, low electronic conductivity. Traditional SOFCs use yttrium-stabilized zirconia (YSZ) as the electrolyte material, which exhibits oxygen ion conductivity but relatively low conductivity, resulting in high operating temperatures (above 800°C) and hindering its widespread application. Therefore, there is an urgent need to develop electrolyte materials with high ionic (oxygen ion or proton) conductivity in the mid-to-low temperature range (400-800°C) to reduce the operating temperature of SOFCs. Electrolyte materials with proton conductivity typically have lower migration activation energies and higher ionic conductivity than oxygen ion conductive electrolyte materials, requiring relatively lower operating temperatures, thus showing greater promise for practical applications.
[0004] Sodium-ion batteries are a novel energy storage technology. Compared to lithium-ion batteries, they offer lower raw material costs, better safety, and higher energy density. Sodium resources are also abundant, with an abundance of 2.64% in the Earth's crust, 440 times that of lithium. Furthermore, sodium resources are widely distributed and easy to extract. Sodium's emergence as a lithium alternative has garnered increasing attention in the battery field. Compared to liquid lithium-ion batteries, solid-state batteries offer advantages such as higher safety, higher energy density, and higher stability.
[0005] Amber generally refers to alkali metal or alkaline earth metal silicate or aluminosilicate minerals with the general formula A2B′(B2O7) and a layered tetrahedral network structure, as well as the solid solutions formed therein. The large A-site cations sandwiched between adjacent tetrahedral layers are in an octagonal coordination environment within a five-membered ring channel. In this special layered structure, when cations at different positions undergo non-equivalent substitution or oxidation, a certain amount of defects can be introduced into the structure, leading to changes in local structure and physical properties. Most reported and extensively studied amber-type electrolytes exhibit oxygen ion conductivity, especially interstitial oxygen ion conductivity; however, amber-type materials exhibiting sodium ion and proton conductivity have not yet been reported. Summary of the Invention
[0006] In view of this, the present invention aims to provide a mixed sodium ion-proton conductive ceramic material, wherein the Ca obtained is... 1- x Na 1+x GaSi2O 7-0.5x Ceramic materials exhibit significantly improved conductivity and proton conductivity even in humid environments, making them promising for applications in both solid oxide fuel cell and sodium-ion battery research.
[0007] To achieve the above objectives, the present invention provides the following technical solution:
[0008] In a first aspect, the present invention provides a mixed sodium ion-proton conductive ceramic material, the composition of which is Ca... 1-x Na 1+x GaSi2O 7-0.5x , where x is 0.1-0.4.
[0009] Further preferably, the electroceramic material Ca 1-x Na 1+x GaSi2O 7-0.5x x is 0.4.
[0010] Preferably, the raw materials for the ceramic material are CaCO3, Na2CO3, Ga2O3, and SiO2;
[0011] The purity of each raw material is ≥99%;
[0012] The particle sizes of the raw materials are CaCO3≤30um, Na2CO3≤10um, Ga2O3≤20um, and SiO2≤1200nm.
[0013] Secondly, the present invention provides a method for preparing a ceramic material, comprising the following steps:
[0014] 1) According to Ca 1-x Na 1+x GaSi2O 7-0.5x Weigh each raw material according to its stoichiometric ratio;
[0015] 2) Mix all the raw materials, grind them, and then dry them;
[0016] 3) The dried raw materials are sequentially processed through the first tableting and pre-calcination to obtain pre-calcined material;
[0017] 4) The pre-fired material is successively crushed, ground, pressed into a second sheet, and sintered to obtain ceramic material.
[0018] Preferably, the grinding in steps 2) and 4) is carried out independently using ethanol wet grinding, and the grinding time is greater than 1 hour.
[0019] Preferably, in step 2), the solution is dried until there is no ethanol solution.
[0020] Further preferably, the drying in step 2) is performed using infrared lamps.
[0021] Preferably, the pressure of the first tablet in step 3) is 2 MPa, and there is no requirement for the pressing thickness.
[0022] Preferably, the pre-firing temperature in step 3) is 900°C and the pre-firing time is 3 hours.
[0023] Preferably, in step 4), the pressure of the first tablet is 2 MPa and the thickness of the tablet is 0.25 cm.
[0024] Preferably, the sintering temperature in step 4) is 1000℃-1100℃, more preferably 1000℃, and the sintering time is 5h.
[0025] Thirdly, the present invention provides the application of the above-mentioned mixed sodium ion-proton conductive ceramic material in solid oxide fuel cells or sodium ion batteries.
[0026] It contains at least the following beneficial technical effects:
[0027] 1) The Ca prepared in this invention 1-x Na 1+x GaSi2O 7-0.5x A series of ceramic materials exhibiting significant sodium ion conductivity were obtained by doping Ca with Na, achieving a conductivity of 1.03 × 10⁻⁶ at 900 °C in air. -2 S / cm, relative to the conductivity of the parent CaNaGaSi2O7 material (2.90×10⁻⁶). -4 The S / cm ratio has increased by nearly two orders of magnitude.
[0028] 2) The Ca prepared in this invention 1-x Na 1+x GaSi2O 7-0.5x EIS impedance tests on ceramic materials under dry nitrogen and humid nitrogen atmospheres showed a significant difference in conductivity, indicating that the material also exhibits proton conductivity under humid conditions.
[0029] 3) The Ca prepared by this invention 1-x Na 1+x GaSi2O 7-0.5xCeramic materials are a type of mixed sodium-ion-proton conductive ceramic material. Compared with oxygen-ion conductor batteries (O-SOFC), solid oxide fuel cells (H-SOFC) with proton conductors as electrolytes have advantages such as high fuel utilization, high theoretical electromotive force, high ion transport number, and low conduction activation energy. They have potential application prospects in both solid oxide fuel cell research and sodium-ion battery research. Attached Figure Description
[0030] Figure 1 These are the X-ray diffraction (XRD) patterns of the conductive ceramic materials prepared in Examples 1 to 5.
[0031] Figure 2 This is a comparison chart of the conductivity of the conductive ceramic materials prepared in Examples 1 to 5 in an air atmosphere.
[0032] Figure 3 These are the complex impedance diagrams of the conductive ceramic materials prepared in Examples 1 and 5. Figures (a) and (b) show the complex impedance diagrams of the parent material CaNaGaSi2O7 at 600°C and 900°C in air, respectively; Figures (c) and (d) show the complex impedance diagrams of CaNaGaSi2O7 at 600°C and 900°C, respectively. 0.6 Na 1.4 GaSi2O 6.8 Complex impedance diagrams of the material at 300°C and 900°C in air atmosphere.
[0033] Figure 4 This is a conductivity diagram of the conductive ceramic material prepared in Example 5 under dry nitrogen and humid nitrogen atmospheres.
[0034] Figure 5 This is a conductivity graph of the conductive ceramic material prepared in Example 5 at 500°C under different moisture pressures. Detailed Implementation
[0035] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.
[0036] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.
[0037] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.
[0038] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. These other embodiments are also covered within the scope of protection of this invention.
[0039] It should also be understood that the specific embodiments described above are only used to explain the present invention, and the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
[0040] The particle sizes of the raw materials used in the following examples are: CaCO3≤30um, Na2CO3≤10um, Ga2O3≤20um, SiO2≤1200nm.
[0041] Example 1
[0042] Design to generate 0.1 mol of the target product CaNaGaSi2O7 material.
[0043] 1) Weigh 0.1 mol CaCO3, 0.05 mol Na2CO3, 0.05 mol Ga2O3, and 0.2 mol SiO2. Then place the weighed raw materials in a mortar, add an appropriate amount of alcohol, grind thoroughly for 1 hour, and dry under an infrared lamp.
[0044] 2) The prepared mixed powder is pressed into tablets using a Φ20 mold, and pre-calcined at 900℃ for 3 hours using a high-temperature solid-state method to obtain the pre-calcined material.
[0045] 3) Crush the pre-fired material, add alcohol and grind it in a mortar to obtain a mixture. Weigh 0.5g, press it into a Φ10 round disc, and sinter it at 1100℃ for 5h to obtain CaNaGaSi2O7 ceramic disc.
[0046] The obtained ceramic pieces were subjected to XRD analysis, see [link to XRD analysis]. Figure 1 .
[0047] Impedance testing was performed on the sintered ceramic sheets using the following method:
[0048] First, platinum paste is applied to both sides of a ceramic sheet in an impedance furnace. After being connected with platinum wire, the sheet is held at 850°C for two hours to allow the organic matter in the platinum paste to volatilize. Then, an EIS test is performed in an air atmosphere. By analyzing the impedance data, its conductivity and complex impedance diagram can be obtained. (See...) Figure 2-3 .
[0049] Example 2:
[0050] Design to generate 0.1 mol of the target product Ca 0.9 Na 1.1 GaSi2O 6.95 Material.
[0051] 1) Weigh 0.09mol CaCO3, 0.055mol Na2CO3, 0.05mol Ga2O3 and 0.2mol SiO2, then place the weighed raw materials in a mortar, add an appropriate amount of alcohol and grind thoroughly for 1 hour, and dry under an infrared lamp;
[0052] 2) The prepared mixed powder is pressed into tablets using a Φ20 mold, and pre-calcined at 900℃ for 3 hours using a high-temperature solid-state method to obtain the pre-calcined material.
[0053] 3) Crush the pre-fired material, add alcohol, grind in a mortar and pestle to obtain a mixture, weigh 0.5g, press into Φ10 discs, and sinter at 1050℃ for 5h to obtain Ca. 0.9 Na 1.1 GaSi2O 6.95 Ceramic shards.
[0054] The obtained ceramic pieces were subjected to XRD analysis, see [link to XRD analysis]. Figure 1 .
[0055] Impedance testing was performed on the sintered ceramic sheets using the following method:
[0056] First, platinum paste is applied to both sides of a ceramic sheet in an impedance furnace. After being connected with platinum wire, the sheet is held at 850°C for two hours to allow the organic matter in the platinum paste to volatilize. Then, an EIS test is performed in air to measure its conductivity. (See attached image.) Figure 2 .
[0057] Example 3:
[0058] Design to generate 0.1 mol of the target product Ca 0.8 Na 1.2 GaSi2O 6.9 Material.
[0059] 1) Weigh 0.08mol CaCO3, 0.06mol Na2CO3, 0.05mol Ga2O3 and 0.2mol SiO2, then place the weighed raw materials in a mortar, add an appropriate amount of alcohol and grind thoroughly for 1 hour, and dry under an infrared lamp;
[0060] 2) The prepared mixed powder is pressed into tablets using a Φ20 mold, and pre-calcined at 900℃ for 3 hours using a high-temperature solid-state method to obtain the pre-calcined material.
[0061] 3) Crush the pre-fired material, add alcohol, grind in a mortar and pestle to obtain a mixture, weigh 0.5g, press into Φ10 discs, and sinter at 1050℃ for 5h to obtain Ca. 0.8 Na 1.2 GaSi2O 6.9 Ceramic shards.
[0062] The obtained ceramic pieces were subjected to XRD analysis, see [link to XRD analysis]. Figure 1 .
[0063] Impedance testing was performed on the sintered ceramic sheets using the following method:
[0064] First, platinum paste is applied to both sides of a ceramic sheet in an impedance furnace. After being connected with platinum wire, the sheet is held at 850°C for two hours to allow the organic matter in the platinum paste to volatilize. Then, an EIS test is performed in air to measure its conductivity. (See attached image.) Figure 2 .
[0065] Example 4:
[0066] Design to generate 0.1 mol of the target product Ca 0.7 Na 1.3 GaSi2O 6.85 Material.
[0067] 1) Weigh 0.07mol CaCO3, 0.065mol NaCO3, 0.05mol Ga2O3, and 0.2mol SiO2. Then place the weighed raw materials in a mortar, add an appropriate amount of alcohol, grind thoroughly for 1 hour, and dry under an infrared lamp.
[0068] 2) The prepared mixed powder is pressed into tablets using a Φ20 mold, and pre-calcined at 900℃ for 3 hours using a high-temperature solid-state method to obtain the pre-calcined material.
[0069] 3) Crush the pre-fired material, add alcohol, grind in a mortar and pestle to obtain a mixture, weigh 0.5g, press into Φ10 discs, and sinter at 1050℃ for 5h to obtain Ca. 0.7 Na 1.3 GaSi2O 6.85 Ceramic shards.
[0070] The obtained ceramic pieces were subjected to XRD analysis, see [link to XRD analysis]. Figure 1 .
[0071] Impedance testing was performed on the sintered ceramic sheets using the following method:
[0072] First, platinum paste is applied to both sides of a ceramic sheet in an impedance furnace. After being connected with platinum wire, the sheet is held at 850°C for two hours to allow the organic matter in the platinum paste to volatilize. Then, an EIS test is performed in air to measure its conductivity. (See attached image.) Figure 2 .
[0073] Example 5:
[0074] Design to generate 0.1 mol of the target product Ca 0.6 Na 1.4 GaSi2O 6.8 Material.
[0075] 1) Weigh 0.06mol CaCO3, 0.07mol NaCO3, 0.05mol Ga2O3, and 0.2mol SiO2. Then place the weighed raw materials in a mortar, add an appropriate amount of alcohol, grind thoroughly for 1 hour, and dry under an infrared lamp.
[0076] 2) The prepared mixed powder is pressed into tablets using a Φ20 mold, and pre-calcined at 900℃ for 3 hours using a high-temperature solid-state method to obtain the pre-calcined material.
[0077] 3) Crush the pre-fired material, add alcohol, grind in a mortar and pestle to obtain a mixture, weigh 0.5g, press into Φ10 discs, and sinter at 1000℃ for 5h to obtain Ca. 0.6 Na 1.4 GaSi2O 6.8 Ceramic shards.
[0078] The obtained ceramic pieces were subjected to XRD analysis, see [link to XRD analysis]. Figure 1 .
[0079] Impedance testing was performed on the sintered ceramic sheets using the following method:
[0080] First, in an impedance furnace, platinum paste is applied to both sides of a ceramic sheet, which is then connected with platinum wire and held at 850°C for two hours to allow the organic matter in the platinum paste to volatilize. Then, EIS tests are performed under air, nitrogen, and humid nitrogen atmospheres. By analyzing the impedance data, its conductivity and complex impedance diagram can be obtained. (See...) Figure 2-4 .
[0081] The ceramic sheet with composition x = 0.4 was tested at 500℃ under different moisture pressures. The method was as follows:
[0082] First, in an impedance furnace, platinum paste is applied to both sides of a ceramic sheet, which is then connected with platinum wire and held at 850°C for two hours to allow the organic matter in the platinum paste to volatilize. Then, EIS tests are performed under different moisture pressures. By analyzing the impedance data, the conductivity under different moisture pressures can be obtained. Figure 5 .
[0083] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A hybrid sodium ion-proton conductive ceramic material, characterized in that, Its composition expression is Ca 1-x Na 1+ x GaSi2O 7-0.5x ,in x It is 0.1-0.4; The raw materials for the ceramic material are CaCO3, Na2CO3, Ga2O3, and SiO2; The preparation method of the mixed sodium ion-proton conductive ceramic material includes the following steps: 1) According to Ca 1-x Na 1+x GaSi2O 7-0.5x Weigh each raw material according to its stoichiometric ratio; 2) Mix all the raw materials, grind them, and then dry them; 3) The dried raw materials are sequentially processed through the first pressing and pre-firing to obtain pre-fired material; 4) The pre-fired material is successively crushed, ground, pressed into a second sheet, and sintered to obtain ceramic material.
2. The mixed sodium ion-proton conductive ceramic material according to claim 1, characterized in that, The purity of each raw material is ≥99%; The particle sizes of the raw materials are: CaCO3≤30um, Na2CO3≤10um, Ga2O3≤20um, SiO2≤1200nm.
3. The mixed sodium ion-proton conductive ceramic material according to claim 1, characterized in that, In steps 2) and 4), the grinding is carried out independently using ethanol wet grinding for 1 hour.
4. The mixed sodium ion-proton conductive ceramic material according to claim 1, characterized in that, In step 2), the solution is dried until no ethanol remains.
5. The mixed sodium ion-proton conductive ceramic material according to claim 1, characterized in that, The pressure of the first tablet in step 3) is 2 MPa.
6. The mixed sodium ion-proton conductive ceramic material according to claim 1, characterized in that, In step 3), the pre-firing temperature is 900℃ and the pre-firing time is 3h.
7. The mixed sodium ion-proton conductive ceramic material according to claim 1, characterized in that, In step 4), the pressure of the first tablet is 2 MPa, and the thickness of the tablet is 0.25 cm.
8. The mixed sodium ion-proton conductive ceramic material according to claim 1, characterized in that, In step 4), the sintering temperature is 1000℃-1100℃ and the sintering time is 5h.
9. The application of the hybrid sodium-ion-proton conductive ceramic material according to any one of claims 1-8 in solid oxide fuel cells or sodium-ion batteries.